199 results on '"Alfred K Njamnshi"'
Search Results
2. Community engagement in research in sub-Saharan Africa: approaches, barriers, facilitators, ethical considerations and the role of gender – a systematic review protocol
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Valirie Ndip Agbor, Luchuo Engelbert Bain, Alfred K Njamnshi, Wepnyu Y Njamnshi, Claudine Akondeng, and Henshaw Eyambe Mandi
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Medicine - Abstract
Introduction Meaningful community engagement (CE) is increasingly being considered the major determinant of successful research, innovation and intervention uptake. Community leaders, policy makers and funders have expressed the need to engage communities in research. CE in research empowers the host community to participate in addressing its own health needs and health disparities while ensuring that researchers understand community priorities. Thus, appropriate CE opens a unique way to promote coproduction, coimplementation and coevaluation, which may strengthen both the sense of inclusion, ownership and the effectiveness of the research life-cycle. The aim of this review is to synthesise available evidence on how to engage communities in research in a gender-sensitive, ethical, culture-appropriate and sustainable way in sub-Saharan Africa (SSA). This protocol has been developed following the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols and follows the guidance provided by the Cochrane Handbook for Systematic Reviews.Methods and analysis A combination of key text words and medical subject headings such as ‘Community Engagement’ or ‘Community Involvement’ will be used to search 009 databases for all literature published between 1 January 2000 and 31 July 2021. Citations retrieved from database searches will be exported into EndNote X9 to remove duplicate citations and imported into Rayyan QCRI for screening. Two independent reviewers will conduct the screening and data extraction process. Disagreements between review authors will be resolved through discussions, consensus a third reviewer serving as a tiebreaker. The risk of bias will be assessed using the 10-item Joanna Briggs Institute Critical Appraisal Checklist for Qualitative Research. The three-staged process described by Thomas and Harden will be used for the thematic and narrative synthesis of findings.Ethics and dissemination This is a systematic review which uses already collected data thus ethical approval not required. Findings will be published in an open access peer-reviewed journal and presented in relevant conferences and workshops.PROSPERO registration number This protocol has been submitted for registration in PROSPERO and has been published under registration number CRD42021282503 .
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- 2022
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3. ‘Slash and clear’ vector control for onchocerciasis elimination and epilepsy prevention: a protocol of a cluster randomised trial in Cameroonian villages
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Robert Colebunders, María-Gloria Basáñez, Alfred K Njamnshi, Joseph Nelson Siewe Fodjo, Melissa Krizia Vieri, Leonard Ngarka, Wepnyu Y Njamnshi, Leonard N Nfor, Michel Karngong Mengnjo, Adam Hendy, Peter A Enyong, and Dennis Palmer
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Medicine - Abstract
Introduction Onchocerciasis, caused by the filarial nematode Onchocerca volvulus, remains endemic in Cameroon despite decades of community-directed treatment with ivermectin (CDTI). CDTI is often hampered by coendemicity with loiasis (another filariasis caused by Loa loa) in some areas. Strong epidemiological evidence suggests that O. volvulus infection increases the risk for onchocerciasis-associated epilepsy (OAE) among Cameroonian children. This highlights the urgent need to strengthen onchocerciasis elimination programmes in mesoendemic/hyperendemic areas. Novel alternative strategies, such as the ‘slash and clear’ (S&C) vector control method, may be required to complement ongoing CDTI to accelerate elimination of transmission. The short-term impact of S&C on the biting rates of the blackfly vectors has been demonstrated in other settings. However, its long-term effectiveness and impact on parasitological and serological markers of onchocerciasis transmission as well as on OAE are still unknown.Methods and analysis We aim to assess the effectiveness of annual S&C interventions combined with CDTI in reducing onchocerciasis transmission and epilepsy incidence. Eight onchocerciasis-endemic villages located
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- 2021
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4. In pursuit of a cure: The plural therapeutic landscape of onchocerciasis-associated epilepsy in Cameroon - A mixed methods study.
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Maya Ronse, Julia Irani, Charlotte Gryseels, Tom Smekens, Serge Ekukole, Caroline Teh Monteh, Peter Tatah Ntaimah, Susan Dierickx, Kristien Verdonck, Robert Colebunders, Alfred K Njamnshi, Sarah O'Neill, and Koen Peeters Grietens
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Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundA high prevalence of epilepsy has been observed in several onchocerciasis-endemic villages in the Sanaga River basin, Cameroon. Recent studies suggest that ivermectin, a drug that is distributed annually with the aim of eliminating onchocerciasis, may have a protective effect against acquiring onchocerciasis-associated epilepsy (OAE). This study, therefore, provides an in-depth understanding of both the complex therapeutic landscape for epilepsy as well as the experiences related to the 'community-directed treatment with ivermectin' (CDTI) campaign in order to identify a more trenchant path forward in the fight against epilepsy.Methodology/principal findingsBased on a mixed methods study combining a qualitative strand with a quantitative survey, we found that epilepsy was perceived to have had an epidemic emergence in the past and was still considered an important health issue in the study area. Socio-economic status, availability and accessibility of drugs and practitioners, as well as perceived aetiology shaped therapeutic itineraries for epilepsy, which included frequenting (in)formal biomedical health care providers, indigenous and/or faith healing practitioners. Ivermectin uptake for onchocerciasis was generally well known and well regarded. The CDTI faced structural and logistical bottlenecks undermining equal access and optimal adherence to the drug.Conclusions/significanceLocally accessible, uninterrupted, sustainable and comprehensive health-service delivery is essential to help alleviate the epilepsy burden on afflicted households. Addressing structural challenges of CDTI and communicating the potential link with epilepsy to local populations at risk could optimize the uptake of this potentially significant tool in OAE prevention.
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- 2021
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5. Onchocerca volvulus and epilepsy: A comprehensive review using the Bradford Hill criteria for causation.
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Robert Colebunders, Alfred K Njamnshi, Sonia Menon, Charles R Newton, An Hotterbeekx, Pierre-Marie Preux, Adrian Hopkins, Michel Vaillant, and Joseph Nelson Siewe Fodjo
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Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundThe possibility that onchocerciasis may cause epilepsy has been suggested for a long time, but thus far, an etiological link has not been universally accepted. The objective of this review is to critically appraise the relationship between Onchocerca volvulus and epilepsy and subsequently apply the Bradford Hill criteria to further evaluate the likelihood of a causal association.MethodsPubMed and gray literature published until September 15, 2020, were searched and findings from original research were synthesized. Adherence to the 9 Bradford Hill criteria in the context of onchocerciasis and epilepsy was determined to assess whether the criteria are met to strengthen the evidence base for a causal link between infection with O. volvulus and epilepsy, including the nodding syndrome.ResultsOnchocerciasis as a risk factor for epilepsy meets the following Bradford Hill criteria for causality: strength of the association, consistency, temporality, and biological gradient. There is weaker evidence supporting causality based on the specificity, plausibility, coherence, and analogy criteria. There is little experimental evidence. Considering the Bradford Hill criteria, available data suggest that under certain conditions (high microfilarial load, timing of infection, and perhaps genetic predisposition), onchocerciasis is likely to cause epilepsy including nodding and Nakalanga syndromes.ConclusionApplying the Bradford Hill criteria suggests consistent epidemiological evidence that O. volvulus infection is a trigger of epilepsy. However, the pathophysiological mechanisms responsible for seizure induction still need to be elucidated.
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- 2021
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6. Characterization of the cognitive and motor changes revealed by the elevated plus maze in an experimental rat model of radiation-induced brain injury
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Alfred K Njamnshi, Nene Ahidjo, Leonard Ngarka, Leonard N Nfor, Michel K Mengnjo, Wepnyu Y Njamnshi, Jonas Guy Basseguin Atchou, Godwin Y Tatah, Louis M Mbaku, Faustin Dong À Zok, and Paul F Seke Etet
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anxiety ,acute radiation syndrome ,cognitive dysfunction ,depression ,elevated plus maze ,gamma rays ,rats ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Background: Experimental models are needed to better understand the pathophysiology of neurodegenerative diseases to develop novel therapeutics. The neuropathology and clinical signs of acute radiation syndrome resemble those of neurodegenerative conditions. We characterized elevated plus maze (EPM) indicators of cognitive and motor impairment in rats exposed to brain-damaging doses of gamma radiation to develop a model for neurological component of the acute radiation syndrome. Materials and Methods: Technetium 99 m was administered once through tail vein to male Wistar rats to reach an absorbed dose of Gamma radiation of 667 mGy (66.7Rad). Animal performance in the EPM was assessed every 14 days. Rats were observed for 9 weeks for the occurrence of systemic and neurological signs. Comparisons were done between irradiated and nonirradiated rats, and in each group with baseline performance. Results: EPM indicators of cognitive and motor impairment, anxiety, and depression were observed concomitantly and increased with the severity of acute radiation syndrome-like systemic and neurological signs. Alterations in EPM indicators appeared 3 weeks postirradiation and their severity increased with time. Notably, arm transitions and the distance covered in the maze were decreased (−56.71% and −73.62%, P < 0.001), as well as open arm entries and time spent in open arms (−77.78% and −76.19%, P < 0.05) and the indicator of thigmotaxis rearing (−92.45, P < 0.001). Conclusions: Our results suggest that irradiated rat performance in the EPM paradigm reflects disease severity and could be used to perform both acute and subchronic pharmacological studies in acute radiation syndrome-like diseases in rats.
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- 2020
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7. Adherence to Antiretroviral Therapy (ART) in Yaoundé-Cameroon: Association with Opportunistic Infections, Depression, ART Regimen and Side Effects.
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Julius Y Fonsah, Alfred K Njamnshi, Charles Kouanfack, Fang Qiu, Dora M Njamnshi, Claude T Tagny, Emilienne Nchindap, Léopoldine Kenmogne, Dora Mbanya, Robert Heaton, and Georgette D Kanmogne
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Medicine ,Science - Abstract
Following global efforts to increase antiretroviral therapy (ART) access in Sub-Saharan Africa, ART coverage among HIV-infected Cameroonians increased from 0% in 2003 to 22% in 2014. However, the success of current HIV treatment programs depends not only on access to ART, but also on retention in care and good treatment adherence. This is necessary to achieve viral suppression, prevent virologic failure, and reduce viral transmission and HIV/AIDS-related deaths. Previous studies in Cameroon showed poor adherence, treatment interruption, and loss to follow-up among HIV+ subjects on ART, but the factors that influence ART adherence are not well known. In the current cross-sectional study, patient/self-reported questionnaires and pharmacy medication refill data were used to quantify ART adherence and determine the factors associated with increased risk of non-adherence among HIV-infected Cameroonians. We demonstrated that drug side-effects, low CD4 cell counts and higher viral loads are associated with increased risk of non-adherence, and compared to females, males were more likely to forego ART because of side effects (p40 years) were less likely to be non-adherent (p
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- 2017
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8. Depressive symptoms in HIV-infected and seronegative control subjects in Cameroon: Effect of age, education and gender.
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Georgette D Kanmogne, Fang Qiu, Félicien E Ntone, Julius Y Fonsah, Dora M Njamnshi, Callixte T Kuate, Roland F Doh, Anne M Kengne, Claude T Tagny, Emilienne Nchindap, Léopoldine Kenmogne, Dora Mbanya, Mariana Cherner, Robert K Heaton, and Alfred K Njamnshi
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Medicine ,Science - Abstract
Depression is a leading cause of HIV/AIDS disease burden; it worsens health outcomes and quality of life. Addressing this problem requires accurate quantification of the extra burden of depression to HIV/AIDS in a given population, and knowledge of the baseline depression prevalence in the general population. There has been no previous study of depression in the general Cameroonian population. The current study attempts to address that important need. We used the Beck Depression Inventory-II to assess the prevalence and severity of depressive symptoms in 270 HIV-infected and seronegative Cameroonians. Univariate analyses showed a trend toward higher depressive symptoms among cases, compared to controls (p = 0.055), and among older subjects (>40 years), compared to younger subjects (≤40 years) (p = 0.059). Analysis of depression severity showed that 33.73% of cases had moderate-to-severe depressive symptoms, compared to 19.8% of controls (p
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- 2017
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9. Changes in HIV Outcomes Following Depression Care in a Resource-Limited Setting: Results from a Pilot Study in Bamenda, Cameroon.
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Bradley N Gaynes, Brian W Pence, Julius Atashili, Julie K O'Donnell, Alfred K Njamnshi, Mbu Eyongetah Tabenyang, Charles Kefie Arrey, Rachel Whetten, Kathryn Whetten, and Peter Ndumbe
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Medicine ,Science - Abstract
BACKGROUND:Little is known about how improved depression care affects HIV-related outcomes in Africa. In a sample of depressed HIV patients in a low income, sub-Saharan country, we explored how implementing measurement-based antidepressant care (MBC) affected HIV outcomes over 4 months of antidepressant treatment. METHODS:As part of a project adapting MBC for use in Cameroon, we enrolled 41 depressed HIV patients on antiretroviral therapy in a pilot study in which a depression care manager (DCM) provided an outpatient HIV clinician with evidence-based decision support for antidepressant treatment. Acute depression management was provided for the first 12 weeks, with DCM contact every 2 weeks and HIV clinician appointments every 4 weeks. We measured HIV clinical and psychiatric outcomes at 4 months. RESULTS:Participants were moderately depressed at baseline (mean Patient Health Questionnaire [PHQ] score = 14.4, range 13.1, 15.6). All HIV clinical outcomes improved by four month follow-up: mean (range) CD4 count improved from 436 (2, 860) to 452 (132, 876), mean (range) log-viral load decreased from 4.02 (3.86, 4.17) to 3.15 (2.81, 3.49), the proportion with virologic suppression improved from 0% to 18%, mean (range) HIV symptoms decreased from 6.4 (5.5, 7.3) to 3.1 (2.5, 3.7), the proportion reporting good or excellent health improved from 18% to 70%, and the proportion reporting any missed ARV doses in the past month decreased from 73% to 55%. Concurrently, psychiatric measures improved. The mean (range) PHQ score decreased from 14.4 (13.1, 15.6) to 1.6 (0.8, 2.4) and 90% achieved depression remission, while mean maladaptive coping style scores decreased and mean adaptive coping scores and self-efficacy scores improved. CONCLUSION:In this pilot study of an evidence-based depression treatment intervention for HIV-infected patients in Cameroon, a number of HIV behavioral and non-behavioral health outcomes improved over 4 months of effective depression treatment. These data are consistent with the hypothesis that better depression care can lead to improved HIV outcomes.
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- 2015
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10. Actigraphy in human African trypanosomiasis as a tool for objective clinical evaluation and monitoring: a pilot study.
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Alfred K Njamnshi, Paul F Seke Etet, Stephen Perrig, Alphonse Acho, Julius Y Funsah, Dieudonné Mumba, Jean-Jacques Muyembe, Krister Kristensson, and Marina Bentivoglio
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Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
Human African trypanosomiasis (HAT) or sleeping sickness leads to a complex neuropsychiatric syndrome with characteristic sleep alterations. Current division into a first, hemolymphatic stage and second, meningoencephalitic stage is primarily based on the detection of white blood cells and/or trypanosomes in the cerebrospinal fluid. The validity of this criterion is, however, debated, and novel laboratory biomarkers are under study. Objective clinical HAT evaluation and monitoring is therefore needed. Polysomnography has effectively documented sleep-wake disturbances during HAT, but could be difficult to apply as routine technology in field work. The non-invasive, cost-effective technique of actigraphy has been widely validated as a tool for the ambulatory evaluation of sleep disturbances. In this pilot study, actigraphy was applied to the clinical assessment of HAT patients.Actigraphy was recorded in patients infected by Trypanosoma brucei gambiense, and age- and sex-matched control subjects. Simultaneous nocturnal polysomnography was also performed in the patients. Nine patients, including one child, were analyzed at admission and two of them also during specific treatment. Parameters, analyzed with user-friendly software, included sleep time evaluated from rest-activity signals, rest-activity rhythm waveform and characteristics. The findings showed sleep-wake alterations of various degrees of severity, which in some patients did not parallel white blood cell counts in the cerebrospinal fluid. Actigraphic recording also showed improvement of the analyzed parameters after treatment initiation. Nocturnal polysomnography showed alterations of sleep time closely corresponding to those derived from actigraphy.The data indicate that actigraphy can be an interesting tool for HAT evaluation, providing valuable clinical information through simple technology, well suited also for long-term follow-up. Actigraphy could therefore objectively contribute to the clinical assessment of HAT patients. This method could be incorporated into a clinical scoring system adapted to HAT to be used in the evaluation of novel treatments and laboratory biomarkers.
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- 2012
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11. Stigma and epilepsy in onchocerciasis-endemic regions in Africa: a review and recommendations from the onchocerciasis-associated epilepsy working group
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Sarah O’Neill, Julia Irani, Joseph Nelson Siewe Fodjo, Denis Nono, Catherine Abbo, Yasuaki Sato, Augustine Mugarura, Housseini Dolo, Maya Ronse, Alfred K. Njamnshi, and Robert Colebunders
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Epilepsy ,Onchocerciasis ,Stigma ,Anti-epileptic treatment ,Nodding syndrome ,Discrimination ,Infectious and parasitic diseases ,RC109-216 ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background In onchocerciasis-endemic areas, particularly in those with a sub-optimal onchocerciasis control programme, a high prevalence of epilepsy is observed. Both onchocerciasis and epilepsy are stigmatizing conditions. The first international workshop on onchocerciasis-associated epilepsy (OAE) was held in Antwerp, Belgium (12–14 October 2017) and during this meeting, an OAE alliance was established. In this paper, we review what is known about epilepsy-associated stigma in onchocerciasis-endemic regions, and present the recommendations of the OAE alliance working group on stigma. Main body For this scoping review, literature searches were performed on the electronic databases PubMed, Scopus and Science Direct using the search terms “epilepsy AND onchocerciasis AND stigma”. Hand searches were also undertaken using Google Scholar, and in total seven papers were identified that addressed epilepsy-related stigma in an onchocercisasis-endemic area. Due to the limited number of published research papers on epilepsy-associated stigma in onchocerciasis-endemic areas, other relevant literature that describes important aspects related to stigma is discussed. The thematic presentation of this scoping review follows key insights on the barriers to alleviating the social consequences of stigma in highly affected onchocerciasis-endemic areas, which were established by experts during the working group on stigma and discrimination at the first international workshop on OAE. These themes are: knowledge gaps, perceived disease aetiology, access to education, marriage restrictions, psycho-social well-being, burden on the care-giver and treatment seeking behaviour. Based on the literature and expert discussions during the OAE working group on stigma, this paper describes important issues regarding epilepsy-related stigma in onchocerciasis-endemic regions and recommends interventions that are needed to reduce stigma and discrimination for the improvement of the psycho-social well-being of persons with epilepsy. Conclusions Educating healthcare workers and communities about OAE, strengthening onchocerciasis elimination programs, decreasing the anti-epileptic treatment gap, improving the care of epilepsy-related injuries, and prioritising epilepsy research is the way forward to decreasing the stigma associated with epilepsy in onchocerciasis-endemic regions.
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- 2019
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12. Impact of 19 years of mass drug administration with ivermectin on epilepsy burden in a hyperendemic onchocerciasis area in Cameroon
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Charlotte Boullé, Alfred K. Njamnshi, Fidèle Dema, Michel K. Mengnjo, Joseph Nelson Siewe Fodjo, Anne-Cécile Zoung-Kanyi Bissek, Patrick Suykerbuyk, Cédric G. Lenou-Nanga, Hugues C. Nana-Djeunga, Joseph Kamgno, Cédric B. Chesnais, Michel Boussinesq, and Robert Colebunders
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Cameroon ,Epilepsy ,Onchocerciasis ,Community study ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Surveys conducted in 1991–1992 in the Mbam Valley (Cameroon) revealed that onchocerciasis was highly endemic, with community microfilarial loads (CMFL) > 100 microfilariae/snip in some villages. Also in 1991–1992, a survey of suspected cases of epilepsy (SCE) found 746 SCE using a questionnaire administered to individuals identified by key informants, with prevalences reaching 13.6% in some communities. From 1998, annual community-directed treatment with ivermectin (CDTI) was implemented to control onchocerciasis. In 2017, a door-to-door household survey was conducted in three of the villages visited in 1991–1992, using a standardized 5-item epilepsy screening questionnaire. Results In 2017, a total of 2286 individuals living in 324 households were screened (582 in Bayomen, 553 in Ngongol and 1151 in Nyamongo) and 112 SCE were identified (4.9%). Neurologists examined 92 of these SCE and confirmed the diagnosis of epilepsy for 81 of them (3.5%). Between the surveys in 1991–1992 and 2017, the prevalence of SCE decreased from 13.6% to 2.5% in Bayomen (P = 0.001), from 8.7% to 6.6% in Ngongol (P = 0.205) and from 6.4% to 5.4% in Nyamongo (P = 0.282). The median age of SCE shifted from 20 (IQR: 12–23) to 29 years (IQR: 18–33; P = 0.018) in Bayomen, from 16 (IQR: 12–21) to 26 years (IQR: 21–39; P
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- 2019
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13. Correction: Dusabimana et al. Surveillance for Onchocerciasis-Associated Epilepsy and Ov16 IgG4 Testing of Children 6–10 Years Old Should Be Used to Identify Areas Where Onchocerciasis Elimination Programs Need Strengthening. Pathogens 2022, 11, 281
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Alfred Dusabimana, Joseph Nelson Siewe Fodjo, Michel Mandro Ndahura, Bruno P. Mmbando, Stephen Raimon Jada, Annelies Boven, Eric De Smet, Tony Ukety, Alfred K. Njamnshi, Anne Laudisoit, Steven Abrams, and Robert Colebunders
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n/a ,Medicine - Abstract
There was an error in the original publication [...]
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- 2022
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14. Surveillance for Onchocerciasis-Associated Epilepsy and OV16 IgG4 Testing of Children 6–10 Years Old Should Be Used to Identify Areas Where Onchocerciasis Elimination Programs Need Strengthening
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Alfred Dusabimana, Joseph Nelson Siewe Fodjo, Michel Mandro Ndahura, Bruno P. Mmbando, Stephen Raimon Jada, Annelies Boven, Eric De Smet, Tony Ukety, Alfred K. Njamnshi, Anne Laudisoit, Steven Abrams, and Robert Colebunders
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onchocerciasis ,onchocerciasis-associated epilepsy ,epilepsy prevalence ,incidence ,ivermectin ,OV16 antibodies ,Medicine - Abstract
To eliminate onchocerciasis-associated morbidity, it is important to identify areas where there is still high ongoing Onchocerca volvulus transmission. Between 2015 and 2021, door-to-door surveys were conducted in onchocerciasis-endemic villages in Cameroon, the Democratic Republic of Congo (DRC), Nigeria, South Sudan, and Tanzania to determine epilepsy prevalence and incidence, type of epilepsy and ivermectin therapeutic coverage. Moreover, children aged between six and 10 years were tested for anti-Onchocerca antibodies using the Ov16 IgG4 rapid diagnostic test (RDT). A mixed-effect binary logistic regression analysis was used to assess significantly associated variables of Ov16 antibody seroprevalence. A high prevalence and incidence of epilepsy was found to be associated with a high Ov16 antibody seroprevalence among 6–10-year-old children, except in the Logo health zone, DRC. The low Ov16 antibody seroprevalence among young children in the Logo health zone, despite a high prevalence of epilepsy, may be explained by a recent decrease in O. volvulus transmission because of a decline in the Simulium vector population as a result of deforestation. In the Central African Republic, a new focus of O. volvulus transmission was detected based on the high Ov16 IgG4 seropositivity among children and the detecting of nodding syndrome cases, a phenotypic form of onchocerciasis-associated epilepsy (OAE). In conclusion, Ov16 IgG4 RDT testing of 6–10-year-old children is a cheap and rapid method to determine the level of ongoing O. volvulus transmission and to assess, together with surveillance for OAE, the performance of onchocerciasis elimination programs.
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- 2022
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15. Report of the first international workshop on onchocerciasis-associated epilepsy
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Robert Colebunders, Michel Mandro, Alfred K. Njamnshi, Michel Boussinesq, An Hotterbeekx, Joseph Kamgno, Sarah O’Neill, Adrian Hopkins, Patrick Suykerbuyk, Maria-Gloria Basáñez, Rory J. Post, Belén Pedrique, Pierre-Marie Preux, Wilma A. Stolk, Thomas B. Nutman, and Richard Idro
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Onchocerciasis ,Epilepsy ,Nodding syndrome ,Nakalanga syndrome ,Prevalence ,Burden of disease ,Infectious and parasitic diseases ,RC109-216 ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Recently, several epidemiological studies performed in Onchocerca volvulus-endemic regions have suggested that onchocerciasis-associated epilepsy (OAE) may constitute an important but neglected public health problem in many countries where onchocerciasis is still endemic. Main text On October 12–14th 2017, the first international workshop on onchocerciasis-associated epilepsy (OAE) was held in Antwerp, Belgium. The workshop was attended by 79 participants from 20 different countries. Recent research findings strongly suggest that O. volvulus is an important contributor to epilepsy, particularly in meso- and hyperendemic areas for onchocerciasis. Infection with O. volvulus is associated with a spectrum of epileptic seizures, mainly generalised tonic-clonic seizures but also atonic neck seizures (nodding), and stunted growth. OAE is characterised by an onset of seizures between the ages of 3–18 years. Multidisciplinary working groups discussed topics such as how to 1) strengthen the evidence for an association between onchocerciasis and epilepsy, 2) determine the burden of disease caused by OAE, 3) prevent OAE, 4) improve the treatment/care for persons with OAE and affected families, 5) identify the pathophysiological mechanism of OAE, and 6) deal with misconceptions, stigma, discrimination and gender violence associated with OAE. An OAE Alliance was created to increase awareness about OAE and its public health importance, stimulate research and disseminate research findings, and create partnerships between OAE researchers, communities, advocacy groups, ministries of health, non-governmental organisations, the pharmaceutical industry and funding organizations. Conclusions Although the exact pathophysiological mechanism underlying OAE remains unknown, there is increasing evidence that by controlling and eliminating onchocerciasis, OAE will also disappear. Therefore, OAE constitutes an additional argument for strengthening onchocerciasis elimination efforts. Given the high numbers of people with epilepsy in O. volvulus-endemic regions, more advocacy is urgently needed to provide anti-epileptic treatment to improve the quality of life of these individuals and their families.
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- 2018
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16. Dementia and cognitive impairment in French-speaking Sub-Saharan Africa: a comprehensive review on moving out of the shadows of neglect
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Cyrille D. Nkouonlack, Wepnyu Y. Njamnshi, Samuel A. Angwafor, Joseph N. Siewe Fodjo, Michel K. Mengnjo, Leonard Ngarka, Maggy Mbede, Leonard N. Nfor, Carlson Abomate, Kevin Nganchfu, Nene Ahidjo, Jonas G. Basseguin Atchou, Edwige L. Mendo, Ignatius Esene, Eta N. Mbong, Eric G. Bila, Roland N. Nchufor, Lorella Vechio, Edmond N. Mouofor, Luc N. Belinga, Julius Y. Fonsah, Edith N. Nsoh, Fidele Dema, Eric S. Chokote, Earnest N. Tabah, Caroline Kenmogne, Yannick N. Wadop, Nono Ponte Kiatoko, Fouksona Sakadi, Emmanuel Epenge, Fatimata H. Djibo, Ibrahim Dardar, Olivier Kapto, Godwin Y. Tatah, Pierre Ongolo-Zogo, Dickson S. Nsagha, Mendinatou A. Houesso, Seybou H. Diallo, Evelyne Diarra, Biniyam A. Ayele, GA. Mpandzou, Eliot Sounga, Paul M. Ossou-Nguiet, Yousoufa Maiga, Christian Napon, Pascal Mbelesso, Maelenn Guerchet, Kamadore Toure, Ange-Eric Koume-Assouan, Alain D. Tehindrazanarivelo, Philomene Kouna, Roman Tchoua, Disman Houinatou, Athanase Millogo, Najib Kissani, Mesua K. Luabeya, Agnon A.K. Balugou, David Nditei, Kouassi Beugre, Kevin Richetin, Serge Vulliemoz, Stephen Perrig, Joelle N. Chabwine, Roman Sztajzel, Daniel Etya'ale, Jean Marie Annoni, Paul F. Seke Etet, Amadi O. Ihunwo, Rose G.F. Leke, Marie Therese Obama Ondoa, Jose E. Cavazos, Gladys Maestre, Sudha Seshadri, Bernard Fongang, and Alfred K. Njamnshi
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Dementia is a global public health problem with increasing prevalence and incidence worldwide. The African continent is expected to bear the biggest brunt of the burden of dementia by 2050 because of the rapid demographic changes, including rapid population growth, an increase in life expectancy, and ageing. However, French-speaking Sub-Saharan African (FS-SSA) countries are underrepresented in research on dementia in Africa. While the reasons are diverse and complex, linguistic and cultural barriers to research, disproportionately affect these countries and may be significant factors. Any efforts, therefore, to redress the burden of dementia in Africa must consider the specific demographic, cultural, and linguistic characteristics of FS-SSA countries. This scoping review explores the current state of knowledge in dementia and cognitive impairment in Sub-Saharan Africa, highlighting research gaps and specific patterns unique to FS-SSA Africa. We identify pathways for research to bridge the knowledge gaps on dementia in FS-SSA as part of the global endeavor to tackle dementia worldwide.
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- 2023
17. Genomic characterization of <scp>HLA</scp> class I and class <scp>II</scp> genes in ethnically diverse <scp>sub‐Saharan</scp> African populations: A report on novel <scp>HLA</scp> alleles
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Ioanna Pagkrati, Jamie L. Duke, Eric Mbunwe, Timothy L. Mosbruger, Deborah Ferriola, Jenna Wasserman, Amalia Dinou, Nikolaos Tairis, Georgios Damianos, Ioanna Kotsopoulou, Joanna Papaioannou, Diamantoula Giannopoulos, William Beggs, Thomas Nyambo, Sununguko W. Mpoloka, Gaonyadiwe G. Mokone, Alfred K. Njamnshi, Charles Fokunang, Dawit Woldemeskel, Gurja Belay, Martin Maiers, Sarah A. Tishkoff, and Dimitri S. Monos
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Immunology ,Genetics ,Immunology and Allergy - Published
- 2023
18. A rare case of drug sensitive adult‐onset temporal lobe epilepsy due to a focal cortical dysplasia revealed by ictal coughing: First report in <scp>sub‐Saharan</scp> Africa
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Eric‐Samuel Chokote, Leonard Ngarka, Emmanuel Oben Takoeta, Hermann Nestor Tsague Kengni, Leonard N. Nfor, Michel K. Mengnjo, Edwige Laure Mendo, Fabrice Djeutcheu, Faustin N. Yepnjio, Godwin Y. Tatah, Hubert Désiré Awa Mbassi, and Alfred K. Njamnshi
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General Medicine - Published
- 2023
19. The Brain Research Africa Initiative (BRAIN)
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Alfred K Njamnshi, Leonard Ngarka, Wepnyu Y Njamnshi, Nene Ahidjo, Joelle N Chabwine, Vladimir Hachinski, Jean Marie Annoni, Joelle Nsimire Chabwine, Alfred Kongnyu Njamnshi, Wepnyu Yembe Njamnshi, Stephen Perrig, and Roman Sztajzel
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Neurology (clinical) - Published
- 2023
20. Adherence to COVID-19 preventive measures in Sub-Saharan Africa during the 1st year of the pandemic: Pooled analysis of the International Citizen Project on COVID-19 (ICPCovid) surveys
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Leonard Ngarka, Joseph Nelson Siewe Fodjo, Wepnyu Yembe Njamnshi, John D. Ditekemena, Mohammed A. M. Ahmed, Rhoda K. Wanyenze, Janet Dula, Philippe Sessou, Christian T. Happi, John N. Nkengasong, Robert Colebunders, and Alfred K. Njamnshi
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Public Health, Environmental and Occupational Health ,Human medicine - Abstract
IntroductionWhile most governments instituted several interventions to stall the spread of COVID-19, little is known regarding the continued observance of the non-pharmaceutical COVID-19 preventive measures particularly in Sub-Saharan Africa (SSA). We investigated adherence to these preventive measures during the initial 6 months of the COVID-19 outbreak in some SSA countries.MethodsBetween March and August 2020, the International Citizen Project on COVID-19 consortium (www.icpcovid.com) conducted online surveys in six SSA countries: Benin, Cameroon, Democratic Republic of Congo, Mozambique, Somalia, and Uganda. A five-point individual adherence score was constituted by scoring respondents' observance of the following measures: mask use, physical distancing, hand hygiene, coughing hygiene, and avoiding to touch one's face. Community behaviors (going to public places, traveling during the pandemic) were also assessed. Data were analyzed in two time periods: Period 1 (March-May) and Period 2 (June-August).ResultsResponses from 26,678 respondents were analyzed (mean age: 31.0 ± 11.1 years; 54.1% males). Mean individual adherence score decreased from 3.80 ± 1.37 during Period 1, to 3.57 ± 1.43 during Period 2; p < 0.001. At the community level, public events/places were significantly more attended with increased travels during Period 2 compared to Period 1 (p < 0.001). Using linear mixed models, predictors of increased individual adherence included: higher age (Coef = 0.005; 95% CI: 0.003–0.007), female gender (Coef = 0.071; 95% CI: 0.039–0.104), higher educational level (Coef = 0.999; 95% CI: 0.885–1.113), and working in the healthcare sector (Coef = 0.418; 95% CI: 0.380–0.456).ConclusionDecreasing adherence to non-pharmaceutical measures over time constitutes a risk for the persistence of COVID-19 in SSA. Younger persons and those with lower education levels constitute target groups for improving adherence to such measures.
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- 2022
21. Epilepsy in the Sanaga‐Mbam valley, an onchocerciasis‐endemic region in Cameroon: electroclinical and neuropsychological findings
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Cédric B Chesnais, Eric Samuel Chokote, Maxime Guillaume, Joseph Nelson Siewe Fodjo, Thierry Tchoumi, Ghislain Nokam, Guillaume Wyart, Dominique Parain, Robert Colebunders, Michel Boussinesq, Tatah Y. Godwin, Alexandre Morin, Alfred K. Njamnshi, Gilles Gargala, Leonard Ngarka, Wepnyu Y. Njamnshi, Mary Bello Nkinin, Department of neurology, university hospital of Rouen, École nationale vétérinaire, agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS), Recherches Translationnelles sur le VIH et les maladies infectieuses endémiques et émergentes (TransVIHMI), Institut de Recherche pour le Développement (IRD)-Université de Yaoundé I-Université Cheikh Anta Diop [Dakar, Sénégal] (UCAD)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM), Epidémiosurveillance de protozooses à transmission alimentaire et vectorielle (ESCAPE), Université de Reims Champagne-Ardenne (URCA)-Université de Rouen Normandie (UNIROUEN), and Normandie Université (NU)-Normandie Université (NU)-Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES)
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Pediatrics ,medicine.medical_specialty ,neuropsychology ,Epilepsy ,[SDV.MHEP.MI]Life Sciences [q-bio]/Human health and pathology/Infectious diseases ,Humans ,Medicine ,Cameroon ,RC346-429 ,[SDV.EE.SANT]Life Sciences [q-bio]/Ecology, environment/Health ,nodding syndrome ,business.industry ,Nodding Syndrome ,onchocerciasis ,Neuropsychology ,Electroencephalography ,electrophysiology ,medicine.disease ,[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology ,Neurology ,Full‐length Original Research ,epilepsy ,Human medicine ,Neurology. Diseases of the nervous system ,Neurology (clinical) ,business ,Onchocerciasis - Abstract
Objective Epilepsy is highly prevalent in onchocerciasis-endemic African regions. Various types of epilepsy have been described in such regions based essentially on clinical characteristics. Methods We conducted a clinical, neurophysiological and neuropsychological study of epilepsy in the onchocerciasis-endemic region of Ntui, Sanaga-Mbam area, Cameroon. Results One hundred and eighty-seven persons with presumed epilepsy were recruited in an epilepsy clinic in Ntui. Epilepsy was clinically confirmed in 144 (79%) subjects, 69 (46.0%) of them met the onchocerciasis-associated epilepsy (OAE) criteria, and 51 of 106 tested (48.1%) presented Ov16 antibodies. Electroencephalograms (EEG) were recorded in 91 participants, of which 36 (33%) were considered abnormal and 27 of 36 (75%) revealed bifrontotemporal spike and slow waves. Concerning the neuropsychological evaluation, 29% showed severe global cognitive impairment, 28% severe episodic memory impairment, and 66% severe frontal cognitive impairment. Half of the persons with epilepsy (PWE) suffered from a mental disorder. Significance In PWE in the Sanaga-Mbam area in Cameroon, we observed EEG patterns similar to those described among persons with OAE, including nodding syndrome in other onchocerciasis-endemic areas. Most PWE presented with severe cognitive impairment. We hypothesize that onchocerciasis may induce neurocognitive disorders and epilepsy via a mechanism that involves mainly the frontal and temporal regions of the brain.
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- 2021
22. Insulin-like growth factor-1 signaling in the tumor microenvironment: Carcinogenesis, cancer drug resistance, and therapeutic potential
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Armel H, Nwabo Kamdje, Paul F, Seke Etet, Maulilio J, Kipanyula, Lorella, Vecchio, Richard, Tagne Simo, Alfred K, Njamnshi, Kiven E, Lukong, and Patrice N, Mimche
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Carcinogenesis ,Drug Resistance, Neoplasm ,Neoplasms ,Endocrinology, Diabetes and Metabolism ,Tumor Microenvironment ,Humans ,Insulin-Like Growth Factor I ,Signal Transduction - Abstract
The tumor microenvironment fuels tumorigenesis and induces the development of resistance to anticancer drugs. A growing number of reports support that the tumor microenvironment mediates these deleterious effects partly by overexpressing insulin-like growth factor 1 (IGF-1). IGF-1 is known for its role to support cancer progression and metastasis through the promotion of neovascularization in transforming tissues, and the promotion of the proliferation, maintenance and migration of malignant cells. Anti-IGF therapies showed potent anticancer effects and the ability to suppress cancer resistance to various chemotherapy drugs in in vivo and in vitro preclinical studies. However, high toxicity and resistance to these agents are increasingly being reported in clinical trials. We review data supporting the notion that tumor microenvironment mediates tumorigenesis partly through IGF-1 signaling pathway. We also discuss the therapeutic potential of IGF-1 receptor targeting, with special emphasis on the ability of IGF-R silencing to overcome chemotherapy drug resistance, as well as the challenges for clinical use of anti-IGF-1R therapies.
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- 2022
23. Vector-borne protozoal infections of the CNS: cerebral malaria, sleeping sickness and Chagas disease
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Josemir W. Sander, Alfred K. Njamnshi, and Gagandeep Singh
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0301 basic medicine ,Chagas disease ,medicine.medical_specialty ,business.industry ,Actigraphy ,medicine.disease ,Diagnostic tools ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Blood smear ,Neurology ,Cerebral Malaria ,medicine ,African trypanosomiasis ,Neurology (clinical) ,Vector (molecular biology) ,Intensive care medicine ,business ,030217 neurology & neurosurgery ,Malaria - Abstract
PURPOSE OF THE REVIEW: Malaria, Chagas Disease and Human African Trypanosomiasis are vector-borne protozoan illnesses, frequently associated with neurological manifestations. Intriguing but ignored, limited mainly to resource-limited, tropical settings, these disorders are now coming to light because of globalisation and improved diagnosis and treatment. Enhanced understanding of these illnesses has prompted this review. RECENT FINDINGS: Methods of diagnosis have currently transitioned from blood smear examinations to immunological assays and molecular methods. Tools to assess neurological involvement, such as magnetic resonance imaging, are now increasingly available in regions and countries with high infection loads. Sleep and other electrophysiological technologies (electroencephalography, actigraphy) are also promising diagnostic tools but requiring field-validation. Access to treatments was formerly limited, even as limitations of agents used in the treatment are increasingly recognised. Newer agents are now being developed and trialled, encouraged by improved understanding of the disorders' molecular underpinnings. SUMMARY: Prompt diagnosis and treatment are crucial in ensuring cure from the infections. Attention should also be due to the development of globally applicable treatment guidelines, the burden of neurological sequelae and elimination of the zoonoses from currently endemic regions.
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- 2021
24. Epidemiology of epilepsy and relationship with onchocerciasis prevalence in villages of the Ntui Health District of Cameroon
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Leonard Ngarka, Joseph Nelson Siewe Fodjo, Calson Ambomatei, Wepnyu Yembe Njamnshi, Julius Ndi Taryunyu Njamnshi, Leonard N. Nfor, Michel K. Mengnjo, and Alfred K. Njamnshi
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Behavioral Neuroscience ,Neurology ,Neurology (clinical) - Published
- 2023
25. Whole-genome sequencing reveals a complex African population demographic history and signatures of local adaptation
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Shaohua Fan, Jeffrey P. Spence, Yuanqing Feng, Matthew E.B. Hansen, Jonathan Terhorst, Marcia H. Beltrame, Alessia Ranciaro, Jibril Hirbo, William Beggs, Neil Thomas, Thomas Nyambo, Sununguko Wata Mpoloka, Gaonyadiwe George Mokone, Alfred K. Njamnshi, Charles Fokunang, Dawit Wolde Meskel, Gurja Belay, Yun S. Song, and Sarah A. Tishkoff
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General Biochemistry, Genetics and Molecular Biology - Published
- 2023
26. The Actigraphy Sleep Score: A New Biomarker for Diagnosis, Disease Staging, and Monitoring in Human African Trypanosomiasis
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Gabriela C. Olivera, Leonard Ngarka, Wepnyu Y. Njamnshi, Martin E. Rottenberg, Leonard N. Nfor, Peter G. E. Kennedy, Stephen Perrig, Alphonse Acho, Marina Bentivoglio, Alfred K. Njamnshi, Jean-Jacques Muyembe, and Paul F. Seke Etet
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Trypanosoma brucei gambiense ,030231 tropical medicine ,Polysomnography ,Stage ii ,Leukocyte Count ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Virology ,White blood cell ,Internal medicine ,parasitic diseases ,medicine ,Humans ,Dementia ,African trypanosomiasis ,Child ,Noninvasive biomarkers ,medicine.diagnostic_test ,business.industry ,Human African trypanosomiasis ,HAT diagnosis ,actigraphy sleep score ,Actigraphy ,staging ,Articles ,Middle Aged ,medicine.disease ,Trypanosomiasis, African ,Infectious Diseases ,medicine.anatomical_structure ,Child, Preschool ,biomarker ,Female ,Parasitology ,Sleep ,business ,Biomarkers ,Disease staging - Abstract
Human African trypanosomiasis (HAT) remains a serious public health problem with diagnostic and treatment challenges in many African countries. The absence of a gold-standard biomarker has been a major difficulty for accurate disease staging and treatment follow-up. We therefore attempted to develop a simple, affordable, and noninvasive biomarker for HAT diagnosis and staging. Simultaneous actigraphy and polysomnography as well as cerebrospinal fluid (CSF) white blood cell (WBC) count, trypanosome presence, and C-X-C motif ligand (CXCL)-10 cytokine levels were performed in 20 HAT patients and nine healthy individuals (controls) using standard procedures. The International HIV Dementia Scale (IHDS) was scored in some patients as a surrogate for clinical assessment. From actigraphic parameters, we developed a novel sleep score and used it to determine correlations with other HAT markers, and compared their performance in differentiating between patients and controls and between HAT stages. The novel actigraphy sleep score (ASS) had the following ranges: 0–25 (healthy controls), 67–103 (HAT stage I), 111–126 (HAT intermediate), and 133–250 (HAT stage II). Compared with controls, stage I patients displayed a 7-fold increase in the ASS (P < 0.01), intermediate stage patients a 10-fold increase (P < 0.001), and HAT stage II patients an almost 20-fold increase (P < 0.001). CXCL-10 showed high interindividual differences. White blood cell counts were only marked in HAT stage II patients with a high interindividual variability. The International HIV Dementia Scale score negatively correlated with the ASS. We report the development and better performance of a new biomarker, ASS, for HAT diagnosis, disease staging, and monitoring that needs to be confirmed in large cohort studies.
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- 2020
27. Prevalence and factors associated with depression among type 2 diabetes patients in a Reference Hospital in Cameroon
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Simeon-Pierre Choukem, Therese Nicole Fouda Mbarga, Desmond Aroke, Yacouba Mapoure, Alfred K. Njamnshi, Valery K. Danwe, and Christian Akem Dimala
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Chronic care ,medicine.medical_specialty ,Multivariate analysis ,business.industry ,General Neuroscience ,Type 2 diabetes ,Logistic regression ,medicine.disease ,030227 psychiatry ,Nephropathy ,03 medical and health sciences ,Psychiatry and Mental health ,0302 clinical medicine ,Pill ,Diabetes mellitus ,Internal medicine ,Medicine ,Neurology (clinical) ,business ,030217 neurology & neurosurgery ,Depression (differential diagnoses) - Abstract
Background Depression is the most common psychiatric disorder in patients with diabetes. We aimed to investigate the prevalence and factors associated with depression in patients with type 2 diabetes and to assess the relationship between depression and attainment of treatment targets. Methods In this cross-sectional study, we included patients with type 2 diabetes who were receiving chronic care in the outpatient diabetes unit of the Douala General Hospital, Cameroon. Depression was assessed using the 9-Item-Patient Health Questionnaire (PHQ-9). Logistic regression models were used to identify independent associations. Results Of the 177 participants, 52 (29.4 %, 95 % CI: 22.8–36.7) had depression. In bivariate analysis factors associated with depression were; age > 48 years, physical inactivity, major life event, pill burden (≥5 medication types and ≥7 tablets/day), nephropathy and neuropathy. In multivariate analysis neuropathy (aOR: 3.25, 95 % CI: 1.47–7.19; p = 0.004) and major life event (aOR: 8.38, 95 % CI: 2.79–25.15; p 7 % (aOR: 2.50, 95 % CI: 1.23–5.00; p = 0.010). Conclusion Depression is common in this group of Cameroonians with type 2 diabetes and is strongly associated with major life event, neuropathy and poor glycaemic control. Our results portray the need to systematically screen and manage depression in patients with type 2 diabetes in this setting.
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- 2020
28. Zoonotic and vector-borne parasites and epilepsy in low-income and middle-income countries
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Samuel A. Angwafor, Alfred K. Njamnshi, Gagandeep Singh, Henry S. Fraimow, and Josemir W. Sander
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030231 tropical medicine ,Malaria, Cerebral ,Vector Borne Diseases ,Neurocysticercosis ,Onchocerciasis ,Parasitic infection ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Epilepsy ,0302 clinical medicine ,Zoonoses ,Environmental health ,Taenia solium ,Parasitic Diseases ,medicine ,Animals ,Humans ,Parasites ,Developing Countries ,Poverty ,Cysticercosis ,business.industry ,Low income and middle income countries ,medicine.disease ,medicine.drug_formulation_ingredient ,Cerebral Malaria ,Vector (epidemiology) ,Neurology (clinical) ,business ,030217 neurology & neurosurgery - Abstract
Zoonotic and vector-borne parasites are important preventable risk factors for epilepsy. Three parasitic infections — cerebral malaria, Taenia solium cysticercosis and onchocerciasis — have an established association with epilepsy. Parasitoses are widely prevalent in low-income and middle-income countries, which are home to 80% of the people with epilepsy in the world. Once a parasitic infection has taken hold in the brain, therapeutic measures do not seem to influence the development of epilepsy in the long term. Consequently, strategies to control, eliminate and eradicate parasites represent the most feasible way to reduce the epilepsy burden at present. The elucidation of immune mechanisms underpinning the parasitic infections, some of which are parasite-specific, opens up new therapeutic possibilities. In this Review, we explore the pathophysiological basis of the link between parasitic infections and epilepsy, and we consider preventive and therapeutic approaches to reduce the burden of epilepsy attributable to parasitic disorders. We conclude that a concerted approach involving medical, veterinary, parasitological and ecological experts, backed by robust political support and sustainable funding, is the key to reducing this burden. Zoonotic and vector-borne parasites are important preventable risk factors for epilepsy. The authors explore the pathophysiological basis of the link between parasitic infections and epilepsy and consider preventive and therapeutic approaches to reduce the epilepsy burden associated with parasitic disorders.
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- 2020
29. Lifestyle and the presence of helminths is associated with gut microbiome composition in Cameroonians
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Ceylan Tanes, Sarah A. Tishkoff, Frederic D. Bushman, Louis J. Taylor, Meagan A. Rubel, Alfred K. Njamnshi, Valantine Ngum Ndze, Kyle Bittinger, Arwa Abbas, Charles Fokunang, Andrew Connell, Julius Y. Fonsah, André Essiane, and Eric Ngwang
- Subjects
Nematoda ,lcsh:QH426-470 ,Population ,Zoology ,Lactose ,Industrialization ,Necator americanus ,Parasite Load ,Host-Parasite Interactions ,Machine Learning ,03 medical and health sciences ,RNA, Ribosomal, 16S ,Helminths ,Animals ,Humans ,Colonization ,Parasites ,Cameroon ,education ,Pathogen ,Life Style ,lcsh:QH301-705.5 ,030304 developmental biology ,0303 health sciences ,education.field_of_study ,Gut microbiome ,Farmers ,biology ,030306 microbiology ,Host (biology) ,Research ,HIV ,biology.organism_classification ,Gastrointestinal Microbiome ,Diet ,TH2 ,lcsh:Genetics ,lcsh:Biology (General) ,Metagenomics ,Diet, Paleolithic ,Hunter-gatherers ,Metagenome ,Ascaris lumbricoides ,Metagenomic sequencing - Abstract
Background African populations provide a unique opportunity to interrogate host-microbe co-evolution and its impact on adaptive phenotypes due to their genomic, phenotypic, and cultural diversity. We integrate gut microbiome 16S rRNA amplicon and shotgun metagenomic sequence data with quantification of pathogen burden and measures of immune parameters for 575 ethnically diverse Africans from Cameroon. Subjects followed pastoralist, agropastoralist, and hunter-gatherer lifestyles and were compared to an urban US population from Philadelphia. Results We observe significant differences in gut microbiome composition across populations that correlate with subsistence strategy and country. After these, the variable most strongly associated with gut microbiome structure in Cameroonians is the presence of gut parasites. Hunter-gatherers have high frequencies of parasites relative to agropastoralists and pastoralists. Ascaris lumbricoides, Necator americanus, Trichuris trichiura, and Strongyloides stercoralis soil-transmitted helminths (“ANTS” parasites) significantly co-occur, and increased frequency of gut parasites correlates with increased gut microbial diversity. Gut microbiome composition predicts ANTS positivity with 80% accuracy. Colonization with ANTS, in turn, is associated with elevated levels of TH1, TH2, and proinflammatory cytokines, indicating an association with multiple immune mechanisms. The unprecedented size of this dataset allowed interrogation of additional questions—for example, we find that Fulani pastoralists, who consume high levels of milk, possess an enrichment of gut bacteria that catabolize galactose, an end product of lactose metabolism, and of bacteria that metabolize lipids. Conclusions These data document associations of bacterial microbiota and eukaryotic parasites with each other and with host immune responses; each of these is further correlated with subsistence practices.
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- 2020
30. Conceptual framework for establishing the African Stroke Organization
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P Adebayo, R Melifonwu, Sarah Belson, Alfred K. Njamnshi, Richard Walker, Albertino Damasceno, Michael Brainin, C Napon, G Scola, P Barasukan, S Zimba, Njideka U Okubadejo, PM Ossou-Nguiet, Rajesh N. Kalaria, Kolawole Wahab, K Hamzat, MB Mateus, Julius A Ogeng'o, K Bateman, M Belo, Albert Akpalu, Biniyam A. Ayele, Rufus Akinyemi, G Ekeng, Y Ogun, Bruce Ovbiagele, Godwin Ogbole, DC Vaz, Ikenna O Onwuekwe, A. Charway‐Felli, Amadou Gallo Diop, P Francis, Stephen M. Davis, Adesola Ogunniyi, Mayowa O. Owolabi, Oyedunni Arulogun, Foad Abd-Allah, J Ademokoya, Peter Sandercock, Fred Stephen Sarfo, AA Ebenezer, and Pamela Naidoo
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Gerontology ,Organizations ,Capacity Building ,business.industry ,media_common.quotation_subject ,medicine.disease ,Article ,Clinical neurology ,Stroke ,Neurology ,Conceptual framework ,Perception ,Africa ,medicine ,Humans ,Lifetime risk ,business ,media_common ,Diversity (politics) - Abstract
Africa is the world’s most genetically diverse, second largest, and second most populous continent, with over one billion people distributed across 54 countries. With a 23% lifetime risk of stroke, Africa has some of the highest rates of stroke worldwide and many occur in the prime of life with huge economic losses and grave implications for the individual, family, and the society in terms of mental capital, productivity, and socioeconomic progress. Tackling the escalating burden of stroke in Africa requires prioritized, multipronged, and inter-sectoral strategies tailored to the unique African epidemiological, cultural, socioeconomic, and lifestyle landscape. The African Stroke Organization (ASO) is a new pan-African coalition that brings together stroke researchers, clinicians, and other health-care professionals with participation of national and regional stroke societies and stroke support organizations. With a vision to reduce the rapidly increasing burden of stroke in Africa, the ASO has a four-pronged focus on (1) research, (2) capacity building, (3) development of stroke services, and (4) collaboration with all stakeholders. This will be delivered through advocacy, awareness, and empowerment initiatives to bring about people-focused changes in policy, clinical practice, and public education. In the spirit of the African philosophy of Ubuntu “I am because we are,” the ASO will harness the power of diversity, inclusiveness, togetherness, and team work to build a strong, enduring, and impactful platform for tackling stroke in Africa.
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- 2020
31. Non-Communicable Neurological Disorders and Neuroinflammation
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Clara Ballerini, Alfred K. Njamnshi, Sharon L. Juliano, Rajesh N. Kalaria, Roberto Furlan, and Rufus O. Akinyemi
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Stroke ,Alzheimer’s disease ,neuroinflammation ,spinal cord injury ,stroke ,traumatic brain injury ,Immunology ,Brain Injuries, Traumatic ,Neuroinflammatory Diseases ,Immunology and Allergy ,Humans ,Neurodegenerative Diseases ,Morbidity ,Aged - Abstract
Traumatic brain injury, stroke, and neurodegenerative diseases represent a major cause of morbidity and mortality in Africa, as in the rest of the world. Traumatic brain and spinal cord injuries specifically represent a leading cause of disability in the younger population. Stroke and neurodegenerative disorders predominantly target the elderly and are a major concern in Africa, since their rate of increase among the ageing is the fastest in the world. Neuroimmunology is usually not associated with non-communicable neurological disorders, as the role of neuroinflammation is not often considered when evaluating their cause and pathogenesis. However, substantial evidence indicates that neuroinflammation is extremely relevant in determining the consequences of non-communicable neurological disorders, both for its protective abilities as well as for its destructive capacity. We review here current knowledge on the contribution of neuroinflammation and neuroimmunology to the pathogenesis of traumatic injuries, stroke and neurodegenerative diseases, with a particular focus on problems that are already a major issue in Africa, like traumatic brain injury, and on emerging disorders such as dementias.
- Published
- 2022
32. Correction: Dusabimana et al. Surveillance for OnchocerciasisAssociated Epilepsy and Ov16 IgG4 Testing of Children 6–10 Years Old Should Be Used to Identify Areas Where Onchocerciasis Elimination Programs Need Strengthening. Pathogens 2022, 11, 281
- Author
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Alfred Dusabimana, Joseph Nelson Siewe Fodjo, Michel Mandro Ndahura, Bruno P. Mmbando, Stephen Raimon Jada, Annelies Boven, Eric De Smet, Tony Ukety, Alfred K. Njamnshi, Anne Laudisoit, Steven Abrams, Robert Colebunders, Boven, Annelies/0000-0003-0713-7491, Dusabimana, Alfred, Siewe Fodjo, Joseph Nelson, Ndahura, Michel Mandro, Mmbando, Bruno P., Jada, Stephen Raimon, Boven, Annelies, De Smet , Eric, Ukety, Tony, Njamnshi, Alfred K., Laudisoit, Anne, ABRAMS, Steven, and Colebunders, Robert
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Microbiology (medical) ,Infectious Diseases ,General Immunology and Microbiology ,Immunology and Allergy ,Molecular Biology - Abstract
There was an error in the original publication [...]
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- 2022
33. The interplay between neuroinfections, the immune system and neurological disorders : a focus on Africa
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Leonard Ngarka, Joseph Nelson Siewe Fodjo, Esraa Aly, Willias Masocha, and Alfred K. Njamnshi
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neuroinfection ,sub-Saharan Africa ,Immunology ,Disease Management ,Review ,RC581-607 ,central nervous system ,Communicable Diseases ,neuroinflammation ,immune system ,Cost of Illness ,Organ Specificity ,Africa ,Humans ,Immunology and Allergy ,Public Health Surveillance ,neuropathy ,Disease Susceptibility ,Human medicine ,Immunologic diseases. Allergy ,Geography, Medical ,Nervous System Diseases ,neurological disorder ,pathogen - Abstract
Neurological disorders related to neuroinfections are highly prevalent in Sub-Saharan Africa (SSA), constituting a major cause of disability and economic burden for patients and society. These include epilepsy, dementia, motor neuron diseases, headache disorders, sleep disorders, and peripheral neuropathy. The highest prevalence of human immunodeficiency virus (HIV) is in SSA. Consequently, there is a high prevalence of neurological disorders associated with HIV infection such as HIV-associated neurocognitive disorders, motor disorders, chronic headaches, and peripheral neuropathy in the region. The pathogenesis of these neurological disorders involves the direct role of the virus, some antiretroviral treatments, and the dysregulated immune system. Furthermore, the high prevalence of epilepsy in SSA (mainly due to perinatal causes) is exacerbated by infections such as toxoplasmosis, neurocysticercosis, onchocerciasis, malaria, bacterial meningitis, tuberculosis, and the immune reactions they elicit. Sleep disorders are another common problem in the region and have been associated with infectious diseases such as human African trypanosomiasis and HIV and involve the activation of the immune system. While most headache disorders are due to benign primary headaches, some secondary headaches are caused by infections (meningitis, encephalitis, brain abscess). HIV and neurosyphilis, both common in SSA, can trigger long-standing immune activation in the central nervous system (CNS) potentially resulting in dementia. Despite the progress achieved in preventing diseases from the poliovirus and retroviruses, these microbes may cause motor neuron diseases in SSA. The immune mechanisms involved in these neurological disorders include increased cytokine levels, immune cells infiltration into the CNS, and autoantibodies. This review focuses on the major neurological disorders relevant to Africa and neuroinfections highly prevalent in SSA, describes the interplay between neuroinfections, immune system, neuroinflammation, and neurological disorders, and how understanding this can be exploited for the development of novel diagnostics and therapeutics for improved patient care.
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- 2022
34. An Eluate of the Medicinal Plant
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Paul F, Seke Etet, Muaawia A, Hamza, Ahmed, El-Tahir, Lorella, Vecchio, Sayed Y, Osman, Gwiria M H, Satti, Mohamed H A, Ismail, Mohammed, Farahna, Alfred K, Njamnshi, and Abdu, Adem
- Abstract
Treatment with ethyl acetate fraction and its fifth eluate (F5) preserved fine motor skills and improved the body weight and blood glucose level. At dose 1.71 mg/kg, F5 kept most parameters comparable to the nondiabetic vehicle group values. GC-MS chromatographic analysis of F5 revealed 36 compounds, the most abundantly expressed (41.8%) being theOur results suggest that subfraction F5 of
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- 2021
35. Redondovirus Diversity and Evolution on Global, Individual, and Molecular Scales
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William Beggs, Thomas B. Nyambo, Ayannah S. Fitzgerald, Frederic D. Bushman, Aoife M. Roche, Michael Campbell, Gaonyadiwe G. Mokone, Sununguko Wata Mpoloka, Charles Fokunang, Alessia Ranciaro, Marisol I. Dothard, Louis J. Taylor, Alfred K. Njamnshi, Meagan A. Rubel, Dawit Woldemeskel, Jevon Graham-Wooten, Audrey Allen, Young Hwang, Eric Mbunwe, Layla A Khatib, Sarah A. Tishkoff, Gurja Belay, Ronald G. Collman, and Simon Thompson
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Rural Population ,Saliva ,Critical Illness ,Respiratory System ,Immunology ,Population ,Genome, Viral ,Biology ,Microbiology ,Genome ,Genetic recombination ,Persistence (computer science) ,Evolution, Molecular ,Viral Proteins ,chemistry.chemical_compound ,Virology ,Prevalence ,Humans ,Periodontitis ,education ,Phylogeny ,Genetics ,Mouth ,education.field_of_study ,DNA Viruses ,DNA replication ,Biodiversity ,DNA Virus Infections ,United States ,DNA-Binding Proteins ,Genetic Diversity and Evolution ,chemistry ,Insect Science ,Africa ,Metagenomics ,Recombination ,DNA - Abstract
Redondoviridae is a newly established family of circular Rep-encoding single-stranded (CRESS) DNA viruses found in the human ororespiratory tract. Redondoviruses were previously found in ∼15% of respiratory specimens from U.S. urban subjects; levels were elevated in individuals with periodontitis or critical illness. Here, we report higher redondovirus prevalence in saliva samples: four rural African populations showed 61 to 82% prevalence, and an urban U.S. population showed 32% prevalence. Longitudinal, limiting-dilution single-genome sequencing revealed diverse strains of both redondovirus species (Brisavirus and Vientovirus) in single individuals, persistence over time, and evidence of intergenomic recombination. Computational analysis of viral genomes identified a recombination hot spot associated with a conserved potential DNA stem-loop structure. To assess the possible role of this site in recombination, we carried out in vitro studies which showed that this potential stem-loop was cleaved by the virus-encoded Rep protein. In addition, in reconstructed reactions, a Rep-DNA covalent intermediate was shown to mediate DNA strand transfer at this site. Thus, redondoviruses are highly prevalent in humans, found in individuals on multiple continents, heterogeneous even within individuals and encode a Rep protein implicated in facilitating recombination. IMPORTANCE Redondoviridae is a recently established family of DNA viruses predominantly found in the human respiratory tract and associated with multiple clinical conditions. In this study, we found high redondovirus prevalence in saliva from urban North American individuals and nonindustrialized African populations in Botswana, Cameroon, Ethiopia, and Tanzania. Individuals on both continents harbored both known redondovirus species. Global prevalence of both species suggests that redondoviruses have long been associated with humans but have remained undetected until recently due to their divergent genomes. By sequencing single redondovirus genomes in longitudinally sampled humans, we found that redondoviruses persisted over time within subjects and likely evolve by recombination. The Rep protein encoded by redondoviruses catalyzes multiple reactions in vitro, consistent with a role in mediating DNA replication and recombination. In summary, we identify high redondovirus prevalence in humans across multiple continents, longitudinal heterogeneity and persistence, and potential mechanisms of redondovirus evolution by recombination.
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- 2021
36. Dementia in Africa: Current evidence, knowledge gaps, and future directions
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Akin Ojagbemi, Kirti Ranchod, O Baiyewu, Albert Akpalu, Biniyam A. Ayele, Temitayo Ayantayo, Oye Gureje, Lingani Mbakile-Mahlanza, Alfred K. Njamnshi, Joseph Yaria, Kirsten Bobrow, Brian A. Lawlor, Godwin Ogbole, Motunrayo Coker, Adesola Ogunniyi, Sudha Seshadri, Richard Walker, Rajesh N. Kalaria, Stella-Maria Paddick, Njideka U Okubadejo, Bruce L. Miller, David M. Ndetei, Maëlenn Guerchet, Judith Bosche, Albertino Damasceno, Udunna C. Anazodo, Thierry Adokonou, Mayowa O. Owolabi, Fred Stephen Sarfo, Margaret A. Pericak-Vance, Andrea Damas, Rufus Akinyemi, University of Ibadan, University College Hospital [Ibadan, Nigeria], Neuroépidémiologie Tropicale (NET), Institut Génomique, Environnement, Immunité, Santé, Thérapeutique (GEIST), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-CHU Limoges-Institut d'Epidémiologie Neurologique et de Neurologie Tropicale-Institut National de la Santé et de la Recherche Médicale (INSERM), Université de Lagos, Université de Yaoundé I, Kwame Nkrumah University of Science and Technology [GHANA] (KNUST), Korle-BU Teaching Hospital [Accra, Ghana], Université de Parakou (UP), Newcastle University [Newcastle], University of Nairobi, Department of Earth Sciences [Addis Ababa], Addis Ababa University (AAU), University of Dodoma [Tanzanie] (UDOM), Université du Botswana, Division of Clinical Pharmacology [Cape Town, South Africa] (Department of Medicine), University of Cape Town, Lawson Health Research Institute [London (ON) Canada], Faculty of Medicine, Eduardo Mondlane University, Maputo, University of Texas Health Science Center at San Antonio [San Antonio], John P. Hussman Institute for Human Genomics, University of Miami Leonard M. Miller School of Medicine (UMMSM), Trinity College Dublin, University of California [San Francisco] (UCSF), and University of California
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Gerontology ,Population ageing ,medicine.medical_specialty ,Candidate gene ,Genotype ,precision medicine ,Apolipoprotein E4 ,consortium ,Disease ,Article ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Developmental Neuroscience ,Acquired immunodeficiency syndrome (AIDS) ,Alzheimer Disease ,Epidemiology ,Medicine ,Dementia ,Humans ,genetics ,030212 general & internal medicine ,Vascular dementia ,Aged ,neuropathology ,business.industry ,Health Policy ,Dementia, Vascular ,biomarkers ,vascular dementia ,Alzheimer's disease ,medicine.disease ,3. Good health ,Psychiatry and Mental health ,Africa ,epidemiology ,[SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie ,Neurology (clinical) ,Geriatrics and Gerontology ,business ,Neurocognitive ,030217 neurology & neurosurgery ,Genome-Wide Association Study ,dementia - Abstract
International audience; In tandem with the ever-increasing aging population in low and middle-income countries, the burden of dementia is rising on the African continent. Dementia prevalence varies from 2.3% to 20.0% and incidence rates are 13.3 per 1000 person-years with increasing mortality in parts of rapidly transforming Africa. Differences in nutrition, cardiovascular factors, comorbidities, infections, mortality, and detection likely contribute to lower incidence. Alzheimer's disease, vascular dementia, and human immunodeficiency virus/acquired immunodeficiency syndrome-associated neurocognitive disorders are the most common dementia subtypes. Comprehensive longitudinal studies with robust methodology and regional coverage would provide more reliable information. The apolipoprotein E (APOE) ε4 allele is most studied but has shown differential effects within African ancestry compared to Caucasian. More candidate gene and genome-wide association studies are needed to relate to dementia phenotypes. Validated culture-sensitive cognitive tools not influenced by education and language differences are critically needed for implementation across multidisciplinary groupings such as the proposed African Dementia Consortium.
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- 2021
37. Onchocerca volvulus transmission in the Mbam valley of Cameroon following 16 years of annual community-directed treatment with ivermectin, and the description of a new cytotype of Simulium squamosum
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Joseph Kamgno, Meryam Krit, Jacobus De Witte, Peter Enyong, Philippe Nwane, Adam Hendy, Jean-Claude Dujardin, Sarah O'Neill, Kenneth Pfarr, Rory J. Post, Christine Laemmer, Robert Colebunders, Michel Boussinesq, Hugues C. Nana-Djeunga, and Alfred K. Njamnshi
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Male ,Veterinary medicine ,Insecticides ,Elimination ,030231 tropical medicine ,Infectious and parasitic diseases ,RC109-216 ,Rural Health ,Onchocerciasis ,Insect Control ,030308 mycology & parasitology ,law.invention ,QH301 ,03 medical and health sciences ,0302 clinical medicine ,Ivermectin ,law ,Dry season ,parasitic diseases ,medicine ,Animals ,Humans ,Simuliidae ,Cameroon ,Simulium squamosum ,Mbam ,0303 health sciences ,Larva ,GE ,biology ,Research ,medicine.disease ,biology.organism_classification ,R1 ,Onchocerca volvulus ,Simulium damnosum ,Insect Vectors ,Infectious Diseases ,Transmission (mechanics) ,Biting ,Parasitology ,Female ,Human medicine ,Seasons ,medicine.drug - Abstract
Background The onchocerciasis focus surrounding the lower Mbam and Sanaga rivers, where Onchocerca volvulus is transmitted by Simulium damnosum s.l. (Diptera: Simuliidae), was historically the largest in the southern regions of Cameroon. Annual community-directed treatment with ivermectin (CDTI) has been taking place since 2000, but recent studies have shown that new infections are occurring in children. We aimed to investigate blackfly biting and O. volvulus transmission rates along the lower Mbam river 16 years after the formal onset of annual CDTI. Methods Black flies were collected for three consecutive days each month between July 2016 and June 2017 at two riverside villages and two inland sites situated 4.9 km and 7.9 km from the riverside. Specimens collected at each site were dissected on one of the three collection days each month to estimate parity rates and O. volvulus infection rates, while the remaining samples were preserved for pool screening. Results In total, 93,573 S. damnosum s.l. black flies were recorded biting humans and 9281 were dissected. Annual biting rates of up to 606,370 were estimated at the riverside, decreasing to 20,540 at 7.9 km, while, based on dissections, annual transmission potentials of up to 4488 were estimated at the riverside, decreasing to 102 and 0 at 4.9 km and 7.9 km, respectively. However, pool screening showed evidence of infection in black flies at the furthest distance from the river. Results of both methods demonstrated the percentage of infective flies to be relatively low (0.10–0.36%), but above the WHO threshold for interruption of transmission. In addition, a small number of larvae collected during the dry season revealed the presence of Simulium squamosum E. This is the first time S. squamosum E has been found east of Lake Volta in Ghana, but our material was chromosomally distinctive, and we call it S. squamosum E2. Conclusions Relatively low O. volvulus infection rates appear to be offset by extremely high densities of biting black flies which are sustaining transmission along the banks of the lower Mbam river. Graphical Abstract
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- 2021
38. Impact of natural selection on global patterns of genetic variation, and association with clinical phenotypes, at genes involved in SARS-CoV-2 infection
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T. Nyambo, Dawit Wolde Meskel, Gaonyadiwe G. Mokone, Sununguko Wata Mpoloka, Jibril Hirbo, Alfred K. Njamnshi, Charles Fokunang, Sabah A. Omar, Michael A. McQuillan, Cesar de la Fuente Nunez, Scott M. Williams, Anastasia Lucas, Daniel J. Rader, Sarah A. Tishkoff, Simon Thompson, Matthew E. B. Hansen, Meghan A. Rubel, William Beggs, Michael Campbell, Gurja Belay, Joseph Park, Marcelo C. R. Melo, Anurag Verma, Giorgio Sirugo, Yuanqing Feng, Chao Zhang, Alessia Ranciaro, and Marylyn D. Ritchie
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Genetics ,Natural selection ,Lineage (genetic) ,Genetic variation ,Haplotype ,Biology ,Phenotype ,Gene ,Selection (genetic algorithm) ,Genetic association - Abstract
We investigated global patterns of genetic variation and signatures of natural selection at host genes relevant to SARS-CoV-2 infection (ACE2, TMPRSS2, DPP4,andLY6E). We analyzed novel data from 2,012 ethnically diverse Africans and 15,997 individuals of European and African ancestry with electronic health records, and integrated with global data from the 1000GP. AtACE2,we identified 41 non-synonymous variants that were rare in most populations, several of which impact protein function. However, three non-synonymous variants were common among Central African hunter-gatherers from Cameroon and are on haplotypes that exhibit signatures of positive selection. We identify strong signatures of selection impacting variation at regulatory regions influencingACE2expression in multiple African populations. AtTMPRSS2, we identified 13 amino acid changes that are adaptive and specific to the human lineage. Genetic variants that are targets of natural selection are associated with clinical phenotypes common in patients with COVID-19.
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- 2021
39. Revisiting Konzo Risk Factors in Three Areas Differently Affected by Spastic Paraparesis in Eastern Democratic Republic of the Congo Discloses a Prominent Role of the Nutritional Status—A Comparative Cross-Sectional Study
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Alfred K. Njamnshi, Marius Baguma, Dieudonné Bahati Shamamba, Espoir Bwenge Malembaka, Alain-Narcisse Matabaro, Esto Bahizire, Joelle Nsimire Chabwine, Jean-Michel Rigo, and Germain Zabaday Mudumbi
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Male ,Manihot ,Adolescent ,Cross-sectional study ,Nutritional Status ,malnutrition ,Article ,cassava ,Disease Outbreaks ,konzo ,03 medical and health sciences ,0404 agricultural biotechnology ,0302 clinical medicine ,Risk Factors ,Environmental health ,Vegetables ,Prevalence ,Humans ,Medicine ,TX341-641 ,Wasting ,Konzo ,Cyanides ,Nutrition and Dietetics ,cyanide poisoning ,business.industry ,Nutrition. Foods and food supply ,Spastic paraparesis ,Outbreak ,Nutritional status ,04 agricultural and veterinary sciences ,medicine.disease ,040401 food science ,South-Kivu ,Malnutrition ,Cross-Sectional Studies ,Paraparesis, Spastic ,Democratic Republic of the Congo ,Cyanide poisoning ,Female ,medicine.symptom ,business ,030217 neurology & neurosurgery ,Food Science - Abstract
This comparative cross-sectional study aimed to better understand the respective contributions of protein malnutrition and cassava-derived cyanide poisoning in the development of konzo. We compared data on nutritional status and cyanide exposure of school-age adolescent konzo-diseased patients to those of non-konzo subjects of similar age from three areas in the Eastern Democratic Republic of the Congo. Our results show that konzo patients had a high prevalence of both wasting (54.5%) and stunting (72.7%), as well as of cyanide poisoning (81.8%). Controls from Burhinyi and those from Idjwi showed a similar profile with a low prevalence of wasting (3.3% and 6.5%, respectively) and intermediate prevalence of stunting (26.7% and 23.9%, respectively). They both had a high prevalence of cyanide poisoning (50.0% and 63.0%, respectively), similar to konzo-patients. On the other hand, controls from Bukavu showed the lowest prevalence of both risk factors, namely chronic malnutrition (12.1%) and cyanide poisoning (27.6%). In conclusion, cassava-derived cyanide poisoning does not necessarily coexist with konzo outbreaks. The only factor differentiating konzo patients from healthy individuals exposed to cyanide poisoning appeared to be their worse nutritional status. This further suggests that, besides the known role of cyanide poisoning in the pathogenesis of konzo, malnutrition may be a key factor for the disease occurrence.
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- 2021
40. Near-Full-Length Genetic Characterization of a Novel HIV-1 Unique Recombinant with Similarities to A1, CRF01_AE, and CRFO2_AG Viruses in Yaoundé, Cameroon
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Arpan Acharya, Julius Y. Fonsah, Alfred K. Njamnshi, Dora Mbanya, and Georgette D. Kanmogne
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0301 basic medicine ,viruses ,Immunology ,Genome, Viral ,Biology ,Genome ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,law ,Phylogenetics ,Virology ,Humans ,Cameroon ,030212 general & internal medicine ,Gene ,Phylogeny ,Subgenomic mRNA ,Recombination, Genetic ,Acquired Immunodeficiency Syndrome ,Molecular Epidemiology ,Phylogenetic tree ,Molecular epidemiology ,virus diseases ,Sequence Notes ,Long terminal repeat ,030104 developmental biology ,Infectious Diseases ,HIV-1 ,Recombinant DNA ,Female - Abstract
Variations in the HIV genome influence HIV/AIDS epidemiology. We report here a novel HIV-1 unique recombinant form (URF) isolated from an HIV-infected female (NACMR092) in Cameroon, based on the analyses of near-full-length viral genome (partial gag, full-length pol, env, tat, rev, vif, vpr, vpu, and nef genes, and partial 3'-long terminal repeat). Phylogeny, recombination breakpoints, and recombination map analyses showed that NACMR092 was infected with a mosaic URF that had eight breakpoints (two in gag, one in pol, one in vpr, two in env, and two in the nef regions), nine subgenomic regions, and included fragments that had important similarities with HIV-1 subtypes A1, CRF02_AG, and CRF01_AE. This novel mosaic URF underscores complex recombination events occurring between HIV-1 subtypes circulating in Cameroon. Continued monitoring and detection of such recombinants and accurate classification of HIV genotype is important for tracking viral molecular epidemiology and antigenic diversity.
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- 2019
41. Parasites and epilepsy: Understanding the determinants of epileptogenesis
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Samuel A. Angwafor, Gail S. Bell, Gagandeep Singh, Alfred K. Njamnshi, and Josemir W. Sander
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Biology ,Bioinformatics ,Epileptogenesis ,03 medical and health sciences ,Behavioral Neuroscience ,Epilepsy ,0302 clinical medicine ,Autoimmune Process ,Taenia solium ,Cortical lesion ,Parasitic Diseases ,medicine ,Animals ,Humans ,Parasites ,Gliosis ,030212 general & internal medicine ,Risk factor ,Taeniasis ,medicine.disease ,medicine.drug_formulation_ingredient ,Neurology ,Neurology (clinical) ,medicine.symptom ,030217 neurology & neurosurgery - Abstract
There is a large body of evidence suggesting that parasites could be a major preventable risk factor for epilepsy in low- and middle-income countries. We review potentially important substrates for epileptogenesis in parasitic diseases. Taenia solium is the most widely known parasite associated with epilepsy, and the risk seems determined mainly by the extent of cortical involvement and the evolution of the primary cortical lesion to gliosis or to a calcified granuloma. For most parasites, however, epileptogenesis is more complex, and other favorable host genetic factors and parasite-specific characteristics may be critical. In situations where cortical involvement by the parasite is either absent or minimal, parasite-induced epileptogenesis through an autoimmune process seems plausible. Further research to identify important markers of epileptogenesis in parasitic diseases will have huge implications for the development of trials to halt or delay onset of epilepsy.
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- 2019
42. Effects of HIV on executive function and verbal fluency in Cameroon
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Anne M. Kengne, Dora M. Njamnshi, Robert K. Heaton, Roland F. Doh, Emilienne Nchindap, Anya Umlauf, Dora Mbanya, Claude Tayou Tagny, Bin Tang, Alfred K. Njamnshi, Julius Y. Fonsah, Léopoldine Kenmogne, Georgette D. Kanmogne, and Donald Franklin
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Adult ,Neurocognitive Disorders ,lcsh:Medicine ,HIV Infections ,Neuropsychological Tests ,Article ,03 medical and health sciences ,Fluency ,Executive Function ,0302 clinical medicine ,Cognition ,Acquired immunodeficiency syndrome (AIDS) ,Wisconsin Card Sorting Test ,Reference Values ,medicine ,Verbal fluency test ,Humans ,030212 general & internal medicine ,Cognitive skill ,Cameroon ,lcsh:Science ,Language ,Multidisciplinary ,lcsh:R ,Neuropsychology ,HIV ,medicine.disease ,3. Good health ,Female ,lcsh:Q ,Psychology ,Cognition Disorders ,Neurocognitive ,030217 neurology & neurosurgery ,Clinical psychology ,Stroop effect - Abstract
HIV-associated neurocognitive disorders (HAND) are frequently associated with impaired executive function and verbal fluency. Given limited knowledge concerning HAND in Sub-Saharan-Africa and lack of Cameroonian adult neuropsychological (NP) test norms, we administered four executive function [Halstead Category Test (HCT), Wisconsin Card Sorting Test (WCST), Color Trails-II (CTT2), and Stroop Color-Word-Interference (SCWT)] and three verbal fluency (Category, Action, and Letter Fluency) tests to 742 adult Cameroonians (395 HIV−, 347 HIV+). We developed demographically-corrected NP test norms and examined the effects of HIV and related variables on subjects’ executive function and verbal fluency. HIV+ subjects had significantly lower T-scores on CTT2 (P = 0.005), HCT (P = 0.032), WCST (P
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- 2018
43. Association between measures of adiposity and blood pressure levels in adult Cameroonians
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Laurent Serges Etoundi Ngoa, Sylvie Ndongo Amougou, Andre Pascal Kengne, Anastase Dzudie, Blaise Barche, Meh Martin Geh, Jerome Boombhi, Alfred K. Njamnshi, Nelson Njedock, Jean Philippe Empana, Eugene Sobngwi, Marcel Azabji, Calypse Ngwasiri, Samuel Kingue, Hamadou Ba, Félicité Kamdem, Armel Njomou, Archange Nzali, and Alain Chichom Mefire
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medicine.medical_specialty ,adiposity ,hypertension ,Receiver operating characteristic ,business.industry ,Diastole ,Body Shape Index ,blood pressure ,General Medicine ,Odds ratio ,Anthropometry ,Logistic regression ,ROC curve ,Blood pressure ,Internal medicine ,medicine ,Medicine ,Cameroon ,business ,Body mass index ,Research Articles ,Research Article - Abstract
Introduction Several anthropometric measurements are variably recommended to assess adiposity in routine practice, with less agreement on their comparative performance. We assessed and compared the relationship of seven anthropometric measures of adiposity—waist circumference (WC), waist‐to‐height ratio (WHtR), Body Mass Index (BMI), Ponderal Index (PI), Conicity Index (C index), A Body Shape Index (ABSI), and Body Roundness Index (BRI)—with blood pressure (BP) levels and prevalent hypertension in adult Cameroonians. Methods Data were collected as Cameroon's contribution to the global May Measurement Month 2017(MMM17) survey. Participants were nonpregnant adults, who had no BP measurement in the past year and with no prior hypertension diagnosis. Hypertension was defined as systolic BP ≥140 mm Hg and/or diastolic ≥90 mm Hg. Odds ratios (ORs) for the presence of hypertension per 1 SD increase in each adiposity metrics were estimated in separate logistic regression models. Assessment and comparison of discrimination used the area under the receiver operating characteristics curve (AUC) and nonparametric methods. Results We included 14 424 participants (8210 [58.25%] female; 39.84 ± 14.33 years). There was a graded association between measures of adiposity and prevalent screen‐detected (newly diagnosed) hypertension, with effect sizes being mostly within the same range across measures of adiposity. AUC for hypertension prediction ranged from 0.709 with PI to 0.721 with BRI for single measures, and from 0.736 to 0.739 with combinations of measures of adiposity. Conclusion WC, WHtR, and BRI were strongly associated with BP and better predicted prevalent hypertension, with effects enhanced with the inclusion of BMI.
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- 2021
44. Onchocerca volvulus and epilepsy: A comprehensive review using the Bradford Hill criteria for causation
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Adrian Hopkins, An Hotterbeekx, Sonia Menon, Robert Colebunders, Alfred K. Njamnshi, Charles R. Newton, Michel Vaillant, Pierre-Marie Preux, Joseph Nelson Siewe Fodjo, University of Antwerp, Antwerp, Belgium., University of Yaoundé [Cameroun], Department of Psychiatry [Oxford] (POWIC), University of Oxford [Oxford]-The Warneford Hospital, Neuroépidémiologie Tropicale (NET), Institut Génomique, Environnement, Immunité, Santé, Thérapeutique (GEIST), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-CHU Limoges-Institut d'Epidémiologie Neurologique et de Neurologie Tropicale-Institut National de la Santé et de la Recherche Médicale (INSERM), Service de l'Information Médicale et de l'Évaluation [CHU Limoges] (SIME), CHU Limoges, Laboratoire de Biostatistique et d'Informatique Médicale, Université de Limoges (UNILIM), Population Health Department [Strassen, Luxembourg] (PHD), and Luxembourg Institute of Health (LIH)
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Nematoda ,Databases, Factual ,Epidemiology ,RC955-962 ,Marine and Aquatic Sciences ,Review ,Onchocerciasis ,Epilepsy ,0302 clinical medicine ,Medical Conditions ,Risk Factors ,Arctic medicine. Tropical medicine ,Medicine and Health Sciences ,Child ,Microfilariae ,biology ,Eukaryota ,Causality ,3. Good health ,Infectious Diseases ,Neurology ,Helminth Infections ,Research Design ,Bradford Hill criteria ,Onchocerca ,Public aspects of medicine ,RA1-1270 ,Neglected Tropical Diseases ,Freshwater Environments ,medicine.medical_specialty ,030231 tropical medicine ,Context (language use) ,Research and Analysis Methods ,Nodding Syndrome ,03 medical and health sciences ,Rivers ,Seizures ,Helminths ,medicine ,Parasitic Diseases ,Animals ,Humans ,Risk factor ,Psychiatry ,business.industry ,Ecology and Environmental Sciences ,Public Health, Environmental and Occupational Health ,Case-control study ,Organisms ,Biology and Life Sciences ,Aquatic Environments ,Bodies of Water ,medicine.disease ,biology.organism_classification ,Tropical Diseases ,Onchocerca volvulus ,Invertebrates ,Case-Control Studies ,Medical Risk Factors ,Earth Sciences ,[SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie ,Human medicine ,business ,Zoology ,030217 neurology & neurosurgery - Abstract
Background The possibility that onchocerciasis may cause epilepsy has been suggested for a long time, but thus far, an etiological link has not been universally accepted. The objective of this review is to critically appraise the relationship between Onchocerca volvulus and epilepsy and subsequently apply the Bradford Hill criteria to further evaluate the likelihood of a causal association. Methods PubMed and gray literature published until September 15, 2020, were searched and findings from original research were synthesized. Adherence to the 9 Bradford Hill criteria in the context of onchocerciasis and epilepsy was determined to assess whether the criteria are met to strengthen the evidence base for a causal link between infection with O. volvulus and epilepsy, including the nodding syndrome. Results Onchocerciasis as a risk factor for epilepsy meets the following Bradford Hill criteria for causality: strength of the association, consistency, temporality, and biological gradient. There is weaker evidence supporting causality based on the specificity, plausibility, coherence, and analogy criteria. There is little experimental evidence. Considering the Bradford Hill criteria, available data suggest that under certain conditions (high microfilarial load, timing of infection, and perhaps genetic predisposition), onchocerciasis is likely to cause epilepsy including nodding and Nakalanga syndromes. Conclusion Applying the Bradford Hill criteria suggests consistent epidemiological evidence that O. volvulus infection is a trigger of epilepsy. However, the pathophysiological mechanisms responsible for seizure induction still need to be elucidated., Author summary There is growing epidemiological evidence that an infection with Onchocerca volvulus (the parasite causing onchocerciasis or river blindness) can trigger epilepsy, including nodding and Nakalanga syndromes. We studied the association between onchocerciasis and epilepsy using previously proposed criteria for causality and found strong arguments in favor of a causal relationship. The risk for children to develop epilepsy seems to be determined by the O. volvulus microfilarial load. However, the mechanism by which the O. volvulus parasite is able to trigger seizures remains to be elucidated. This form of epilepsy, called onchocerciasis-associated epilepsy (OAE), is an important public health problem in onchocerciasis-endemic regions with nonexistent or suboptimal onchocerciasis elimination programs. OAE is often characterized by sudden seizure onset in previously healthy children, between 3 to 18 years, without any other obvious cause of epilepsy. On the basis of the findings presented in this paper, it appears that onchocerciasis control may be able to prevent OAE. This further highlights the importance to eliminate onchocerciasis, particularly in areas with a high burden of epilepsy.
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- 2021
45. Vector-borne protozoal infections of the CNS: cerebral malaria, sleeping sickness and Chagas disease
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Gagandeep, Singh, Alfred K, Njamnshi, and Josemir W, Sander
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Trypanosomiasis, African ,Malaria, Cerebral ,Animals ,Humans ,Chagas Disease - Abstract
Malaria, Chagas Disease and Human African Trypanosomiasis are vector-borne protozoan illnesses, frequently associated with neurological manifestations. Intriguing but ignored, limited mainly to resource-limited, tropical settings, these disorders are now coming to light because of globalisation and improved diagnosis and treatment. Enhanced understanding of these illnesses has prompted this review.Methods of diagnosis have currently transitioned from blood smear examinations to immunological assays and molecular methods. Tools to assess neurological involvement, such as magnetic resonance imaging, are now increasingly available in regions and countries with high infection loads. Sleep and other electrophysiological technologies (electroencephalography, actigraphy) are also promising diagnostic tools but requiring field-validation. Access to treatments was formerly limited, even as limitations of agents used in the treatment are increasingly recognised. Newer agents are now being developed and trialled, encouraged by improved understanding of the disorders' molecular underpinnings.Prompt diagnosis and treatment are crucial in ensuring cure from the infections. Attention should also be due to the development of globally applicable treatment guidelines, the burden of neurological sequelae and elimination of the zoonoses from currently endemic regions.
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- 2021
46. Incidence and prevalence of epilepsy and associated factors in a health district in North-West Cameroon: A population survey
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Leonard N. Nfor, Earnest Njih Tabah, Samuel A. Angwafor, Leonard Ngarka, Theophilus Ngeh Njamnshi, Josemir W. Sander, Gail S. Bell, Willem M. Otte, and Alfred K. Njamnshi
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Adult ,Rural Population ,medicine.medical_specialty ,Multivariate analysis ,Neurocysticercosis ,Population ,03 medical and health sciences ,Behavioral Neuroscience ,Epilepsy ,0302 clinical medicine ,Environmental health ,Epidemiology ,medicine ,Prevalence ,Humans ,030212 general & internal medicine ,Cameroon ,education ,education.field_of_study ,business.industry ,Rural health ,Incidence (epidemiology) ,Incidence ,medicine.disease ,Cross-Sectional Studies ,Neurology ,Case-Control Studies ,Neurology (clinical) ,Onchocerciasis ,business ,030217 neurology & neurosurgery - Abstract
This population-based cross-sectional survey with a follow-up case-control study assessed the prevalence, incidence, and risk factors for epilepsy in a rural health district in the North-West Region of Cameroon. Community-based epilepsy screening targeted all inhabitants, six years and older, in all 16 health areas in the Batibo Health District. During door-to-door visits, trained fieldworkers used a validated questionnaire to interview consenting household heads to screen for epilepsy in eligible residents. Trained physicians subsequently assessed people with suspected seizures. After clinical assessment, they confirmed or refuted the diagnosis and estimated the date of epilepsy onset. A trained nurse interviewed people with epilepsy and randomly selected healthy individuals, obtaining relevant demographic details and information on exposure to risk factors for epilepsy. Out of 36,282 residents screened, 524 had active epilepsy. The age-standardized prevalence of active epilepsy was 33.9/1,000 (95% CI: 31.0-37.1/1,000). We estimated the one-year age-standardized epilepsy incidence at 171/100,000 (95%CI: 114.0-254.6). Active epilepsy prevalence varied widely between health areas, ranging between 12 and 75 per 1,000. The peak age-specific prevalence was in the 25-34 age group. In adults, multivariate analysis showed that having a relative with epilepsy was positively associated with epilepsy. Epilepsy characteristics in this population, geographical heterogeneity, and the age-specific prevalence pattern suggest that endemic neurocysticercosis and onchocerciasis may be implicated. Further investigations are warranted to establish the full range of risk factors for epilepsy in this population.
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- 2021
47. In pursuit of a cure: The plural therapeutic landscape of onchocerciasis-associated epilepsy in Cameroon – A mixed methods study
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Susan Dierickx, Koen Peeters Grietens, Sarah O'Neill, Kristien Verdonck, Caroline Teh Monteh, Maya Ronse, Alfred K. Njamnshi, Charlotte Gryseels, Robert Colebunders, Serge Ekukole, Julia Irani, Tom Smekens, Peter Tatah Ntaimah, Brussels Interdisciplinary Research centre on Migration and Minorities, History, Archeology, Arts, Philosophy and Ethics, Centre of Expertise on Gender, Diversity and Intersectionality, and Vrije Universiteit Brussel
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Male ,Etiology ,RC955-962 ,Social Sciences ,Surveys ,Onchocerciasis ,Pathology and Laboratory Medicine ,Cultural Anthropology ,Geographical Locations ,Epilepsy ,Ivermectin ,Medical Conditions ,Sociology ,Arctic medicine. Tropical medicine ,Surveys and Questionnaires ,Health care ,Medicine and Health Sciences ,Prevalence ,Medicine ,Cameroon ,Pharmaceutics ,Sciences bio-médicales et agricoles ,Qualitative Studies ,Middle Aged ,Religion ,Infectious Diseases ,Neurology ,Helminth Infections ,Research Design ,Female ,Public aspects of medicine ,RA1-1270 ,medicine.drug ,Research Article ,Neglected Tropical Diseases ,Adult ,Faith healing ,Research and Analysis Methods ,Indigenous ,Sciences sociales ,Drug Therapy ,Environmental health ,Parasitic Diseases ,Humans ,Quantitative survey ,Survey Research ,business.industry ,Public Health, Environmental and Occupational Health ,medicine.disease ,Tropical Diseases ,Cross-Sectional Studies ,Socioeconomic Factors ,Anthropology ,People and Places ,Africa ,Human medicine ,business ,Qualitative research - Abstract
Background A high prevalence of epilepsy has been observed in several onchocerciasis-endemic villages in the Sanaga River basin, Cameroon. Recent studies suggest that ivermectin, a drug that is distributed annually with the aim of eliminating onchocerciasis, may have a protective effect against acquiring onchocerciasis-associated epilepsy (OAE). This study, therefore, provides an in-depth understanding of both the complex therapeutic landscape for epilepsy as well as the experiences related to the ‘community-directed treatment with ivermectin’ (CDTI) campaign in order to identify a more trenchant path forward in the fight against epilepsy. Methodology/Principal findings Based on a mixed methods study combining a qualitative strand with a quantitative survey, we found that epilepsy was perceived to have had an epidemic emergence in the past and was still considered an important health issue in the study area. Socio-economic status, availability and accessibility of drugs and practitioners, as well as perceived aetiology shaped therapeutic itineraries for epilepsy, which included frequenting (in)formal biomedical health care providers, indigenous and/or faith healing practitioners. Ivermectin uptake for onchocerciasis was generally well known and well regarded. The CDTI faced structural and logistical bottlenecks undermining equal access and optimal adherence to the drug. Conclusions/Significance Locally accessible, uninterrupted, sustainable and comprehensive health-service delivery is essential to help alleviate the epilepsy burden on afflicted households. Addressing structural challenges of CDTI and communicating the potential link with epilepsy to local populations at risk could optimize the uptake of this potentially significant tool in OAE prevention., Author summary Regions where onchocerciasis–a parasitical infection transmitted by blackflies–is endemic also tend to suffer from high levels of epilepsy. Recent studies suggest that ivermectin, an anti- onchocerciasis drug distributed annually to entire populations in onchocerciasis-endemic regions, may protect against developing onchocerciasis-associated epilepsy (OAE). As the link between onchocerciasis and epilepsy has been poorly understood and scientifically neglected in the past, our mixed methods research investigated how residents in an affected Cameroonian area perceive and cope with epilepsy; how they interpret the (causes of the) illness; where they seek care and why there. Armed with this knowledge, epilepsy control programs can optimize interventions geared at relieving the burden of epilepsy–and potentially OAE–which is essential given the fact that, despite 15–20 years of ivermectin distribution, onchocerciasis transmission persists and epilepsy prevalence in these regions remains high. Our findings illustrate how crucial it is to ensure locally accessible, uninterrupted, sustainable and comprehensive health service delivery for epilepsy. Furthermore, the structural challenges associated with the mass ivermectin distribution campaign must be addressed in order to relieve the burden of onchocerciasis, and potentially OAE. Without first addressing these structural bottlenecks, uptake and adherence to ivermectin treatment will remain insufficient.
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- 2021
48. Association between Ov16 seropositivity and neurocognitive performance among children in rural Cameroon : a pilot study
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Robert Colebunders, Wepnyu Y. Njamnshi, Alfred K. Njamnshi, Leonard Ngarka, Kevin Nganchfu, Noelar N. Mundih, Joseph Nelson Siewe Fodjo, Rachel Yerema, Earnest Njih Tabah, Hilda T. Ekwoge, Constance Ayuk, George Ashu, Pernelle Ngoundjou, Edward Awasume, Kongnyu G. Njamnshi, and Leonard N. Nfor
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Pediatrics ,medicine.medical_specialty ,Ov16 ,biology ,business.industry ,Neuropsychology ,medicine.disease ,biology.organism_classification ,Onchocerca volvulus ,Confidence interval ,Article ,Onchocerciasis-associated epilepsy ,Epilepsy ,parasitic diseases ,Medicine ,Verbal fluency test ,Dementia ,Psychology ,Neurocognitive assessment ,Cameroon ,Human medicine ,business ,Onchocerciasis ,Neurocognitive - Abstract
Infection with Onchocerca volvulus was recently reported to increase the risk for epilepsy in Cameroonian children. We investigated whether infection with O. volvulus may alter the cognitive function of children who may or may not develop epilepsy later in their lifetime. Using rapid diagnostic tests, we determined the presence of Ov16 antibodies in 209 school-aged children without epilepsy recruited from three Cameroonian villages, as a proxy for onchocerciasis exposure. In addition, the neurocognitive performance of these children was assessed using a battery of validated tools. Participants were aged 6–16 years, and 46.4% were Ov16 seropositive. Upon standardizing age-specific neurocognitive scores and investigating predictors of neurocognitive performance using multiple linear regression models (adjusted for gender, education level, previous ivermectin use, and anthropometric parameters), we found that being Ov16-positive was significantly associated with reduced semantic verbal fluency (estimate –0.38; 95% confidence interval –0.65 to –0.11; p = 0.006) and lower scores on the International HIV Dementia Scale (estimate –0.31; confidence interval –0.56 to –0.04; p = 0.025). Furthermore, an increasing frequency of past ivermectin use was associated with increased neurocognitive scores. Our findings suggest that exposure to O. volvulus may affect neurocognitive performance of children.
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- 2021
49. Fear and depression during the COVID-19 outbreak in Cameroon : a nation-wide observational study
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Cyrille Nkouonlack, Jean-Marie Annoni, Eric Samuel Chokote, Godwin Y. Tatah, Rose G. F. Leke, Dickson Shey Nsagha, Roman Sztajzel, Paul F. Seke Etet, John N. Nkengasong, Nene Ahidjo, Edwige Laure Mendo, Nancy Palmer, Samuel A. Angwafor, Alfred K. Njamnshi, Dennis Palmer, Robert Colebunders, Leonard Ngarka, Leonard N. Nfor, Marie-Therese Obama, Julius Y. Fonsah, Anne-Cécile Zoung-Kanyi Bissek, Fidèle Dema, Daniel E. Etya’ale, Stephen Perrig, Edith N. Njit, Wepnyu Y. Njamnshi, Jonas Guy Atchou Basseguin, Michel K. Mengnjo, and Joseph Nelson Siewe Fodjo
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Adult ,Male ,Multivariate analysis ,FCV-19S ,RC435-571 ,Odds ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,030212 general & internal medicine ,Cameroon ,Pandemics ,Depression (differential diagnoses) ,Psychiatry ,business.industry ,Depression ,SARS-CoV-2 ,Research ,Outbreak ,COVID-19 ,Fear ,PHQ-9 ,Patient Health Questionnaire ,Psychiatry and Mental health ,Distress ,Anxiety ,Observational study ,Female ,Human medicine ,medicine.symptom ,business ,030217 neurology & neurosurgery ,Demography - Abstract
BackgroundThe COVID-19 pandemic has been associated with significant psychological and social distress worldwide. We investigated fear and depression among adults in Cameroon during different phases of the COVID-19 outbreak.MethodsAn online survey was conducted in Cameroon from June–December 2020 using a structured questionnaire. Socio-demographic data and information regarding COVID-19 history were obtained. Fear and depressive symptoms were assessed using the Fear of COVID-19 score (FCV-19S) and the Patient Health Questionnaire (PHQ-9), respectively. Responses were clustered in weeks to better appreciate their evolution over time.ResultsOverall, 7381 responses from all ten regions of Cameroon were analysed (median age: 30 years, 73.3% male). The prevalence of depression (PHQ-9 score ≥ 10) was 8.4%, and that of high fear of COVID-19 (FCV-19S scores ≥19) was 57.4%. These rates were similar across genders, age-groups, and region of residence. While mean weekly PHQ-9 scores remained fairly stable throughout the study period (range: 2.53–3.21;p = 0.101), mean FCV-19S scores were highest during the early weeks but decreased significantly thereafter (from 20.31 to 18.34;p ConclusionDepression amidst the COVID-19 crisis is less prevalent in Cameroon than in other countries. Prompt and widespread dissemination of adequate COVID-19 information may reduce the risks for depression by dispelling fear and anxiety among Cameroonians.
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- 2021
50. Garcinia kola improves cognitive and motor function of a rat model of acute radiation syndrome in the elevated plus maze
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Michel K. Mengnjo, Edmond Ngwafong Mouofo, Leonard N. Nfor, Nene Ahidjo, Alfred K. Njamnshi, Jonas G. Basseguin Atchou, Paul F. Seke Etet, Wepnyu Y. Njamnshi, Bonaventure T. Ngadjui, Godwin Y. Tatah, Faustin Dong A Zok, Wilfred Ngwa, and Leonard Ngarka
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Vitamin ,Elevated plus maze ,Garcinia kola ,Context (language use) ,motor and cognitive impairment ,Pharmacology ,acute radiation syndrome ,Cachexia ,chemistry.chemical_compound ,anxiety-depression ,Medicine ,Thigmotaxis ,biology ,AcademicSubjects/SCI01870 ,business.industry ,General Engineering ,Acute Radiation Syndrome ,Ascorbic acid ,medicine.disease ,biology.organism_classification ,chemistry ,Gamma radiation ,Original Article ,AcademicSubjects/MED00310 ,business - Abstract
We reported recently that the elevated plus maze is a good tool for evaluating cognitive and motor functional changes in gamma-irradiated rats as a model for new drug evaluation and monitoring. The capacity of Garcinia kola to mitigate radiation-induced brain injury is currently unknown. We therefore assessed the effects of the neuroprotective medicinal plant Garcinia kola, on the cognitive and motor changes in this murine model of acute radiation syndrome. Wistar rats exposed once to an ionizing dose of Tc99m-generated Gamma radiation were treated with an ethyl acetate fraction of methanolic extract of Garcinia kola seeds (content of 100 mg/kg of extract) for 9 weeks. Cognitive and motor function indicators were assessed in the elevated plus maze in these animals and compared with irradiated control groups (vitamin C- and vehicle-treated groups) and the non-irradiated control rats. The irradiated control group displayed cachexia, shaggy and dirty fur, porphyrin deposits around eyes, decreased exploratory activity, reduced social interactions and a loss of thigmotaxis revealed by a marked decrease in rearing episodes and stretch attend posture episodes close to the walls of elevated plus maze closed arm, an increased central platform time, and decreases in open arm time and entries. This group further displayed a decrease in head dips and grooming episodes. Treatment with Garcinia kola, and in a lesser extent vitamin C, significantly prevented the body weight loss (P, The effects of G. kola (a medicinal plant in African traditional medicine) seed extract on the cognitive and motor changes in the murine model of acute radiation syndrome were assessed. The extract was found to mitigate body weight loss, cognitive and motor impairment in irradiated rats better than vitamin C., Graphical Abstract Graphical Abstract
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- 2021
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