20 results on '"de Sousa DR"'
Search Results
2. O redescobrimento luso-brasileiro
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Maria João Marques Gomes, Dr., Renato Sotto-Mayor, Dr., António Ramalho de Almeida, Dr., Francisco Elmano Marques de Sousa, Dr., Luiz Carlos Corrêa da Silva, Dr., and Bruno Carlos Palombini, Dr.
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Diseases of the respiratory system ,RC705-779 - Published
- 1999
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3. (Re)connect social and environmental responsibility to learners’ living environments: Curriculum challenges and possible solutions for teaching-learning in Life Orientation
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Swarts, Dr P., primary, Rens, Prof J.A., additional, and de Sousa, Dr L.O., additional
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- 2018
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4. Toward prevention of cowdriosis: A closer look with the digital holographic microscope 25 years after a first study of the IFN system in the bovine species
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Pedregal, A, de Sousa, DR, Nguyen, HN, das Neves, EA, Lowagie, S, Marique, T, Kagye, N, Guerra, IT, Kamba, Y, Totté, Philippe, Vachiery, Nathalie, Lefrançois, Thierry, Martinez, D, Yourassowsky, C, Callens, N, Monnom, O, Dubois, F, Werenne, J, ProdInra, Migration, and Inconnu
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Vaccin ,[SDV]Life Sciences [q-bio] ,Ehrlichia ,Culture de cellule ,L73 - Maladies des animaux ,[SDV] Life Sciences [q-bio] ,Interféron ,Ehrlichia ruminantium ,Microscopie - Abstract
Mass production of Ehrlichia ruminantium variants from different regions of sub- Saharan Africa is one of the difficulties that must be overcome in producing a heartwater vaccine. Vaccine productivity can be limited by endogenous induction of interferon (IFN), which inhibits the propagation of Ehrlichia ruminantium (ER) in cell culture. Different kinds of endothelial cells, in which ER multiply efficiently, could be grown in a scalable way in VueLife Teflon bags on Cytodex 3 microcarriers where bead-to-bead transfer of cells occurs. The digital holographic microscope designed at the Universit´e Libre de Bruxelles allows detection of the most appropriate time to harvest intracellular microorganisms for vaccine production.
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- 2008
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5. Cutaneous glands of the striped toad, Rhinella crucifer (Wied-Neuwied, 1821) (Amphibia: Bufonidae): Histological study and bioactivities of glandular secretions.
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Barbosa GG, Silva TL, de Oliveira APS, de Albuquerque Lima T, da Silva PM, de Santana CJC, Vieira JRC, de Sousa DR, Souza FAL, Pereira R, Zingali RB, Costa RMPB, Paiva PMG, Rodrigues GG, Castro MS, and Napoleão TH
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- Animals, Male, Female, Exocrine Glands metabolism, Bodily Secretions chemistry, Amphibian Proteins metabolism, Amphibian Proteins pharmacology, Bufonidae metabolism, Skin metabolism, Skin chemistry
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This study investigated the morphology of Rhinella crucifer cutaneous glands, as well as the protein/peptide profiles and bioactivities of body gland secretions (BGS) and parotoid macrogland secretions (PS). The parotoid as well as dorsal and ventral skin fragments of male and female individuals were processed for histological analysis. The protein and peptide profiles of male and female gland secretions were evaluated. Male secretions were also assessed for proteolytic, trypsin inhibiting, hemagglutinating, hemolytic, antimicrobial, and anticoagulant activities. The R. crucifer skin structure presented protuberances that are clearly visible and formed by the integument, which has cutaneous glands throughout the body. An average of 438 and 333 glands were identified in males in females, respectively. No significant differences were observed in the distribution of glands across the body as well as for area and perimeter of glands. Differences were observed in protein composition between the PS and BGS from males and females, and secretions from animals collected from undisturbed and anthropogenically disturbed areas. Proteins with similarities to catalase and elongation factor 1-alpha were detected in the PS. Zymography revealed proteolytic activity in both male BGS and PS. Male BGS showed antibacterial activity against Enterococcus faecalis and Escherichia coli and anticoagulant activity, being able to prolong prothrombin time by 6.34-fold and activated partial thromboplastin time by 2.17-fold. Finally, male PS and BGS caused a maximum hemolysis degree of 1.4%. The data showed that the cutaneous secretions of R. crucifer are potentially promising for biotechnological prospecting., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)
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- 2024
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6. Chronic Chagas Cardiomyopathy in the Brazilian Amazon region: clinical characteristics and regional distinctiveness.
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Guevara Moctezuma EI, Smith Doria S, Ortiz JV, Teixeira de Sousa DR, Mwangi VI, do Nascimento Couceiro K, Brandão ARJ, Guerra JAO, Vale Barbosa Guerra MDG, and Barbosa Bemfica Ferreira JM
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- Humans, Brazil epidemiology, Retrospective Studies, Cross-Sectional Studies, Chagas Cardiomyopathy diagnosis, Chagas Cardiomyopathy epidemiology, Chagas Disease diagnosis, Chagas Disease epidemiology
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Objectives: This study aims to provide a comprehensive analysis of clinical and epidemiological data related to Chronic Chagas Cardiomyopathy (CCC) in the Amazon region of Brazil., Methods: A review of observational, retrospective, and cross-sectional studies related to Chagas Disease in the Amazon region of Brazil was conducted, and a case series addressing CCC in patients treated at the FMT-HVD outpatient clinic, a reference center for Chagas disease in Brazil, was carried out., Results: Clinical characteristics of 55 patients from the Amazon region with CCC were described. The most common electrocardiographic alteration observed was abnormal ventricular repolarization (AVR), present in 40% of cases. The most common echocardiographic finding was left ventricular systolic dysfunction (49%), followed by akinesia or hypokinesia of the inferior and/or inferolateral walls (38.1%) and the presence of an apical aneurysm (32.7%)., Conclusions: Overall, this study demonstrates that CCC in the Amazon region presents clinical characteristics and severity that are similar to those observed in other regions. However, certain peculiarities, such as the frequency of right bundle branch block (RBBB) and anterior and septal involvement during the acute phase, require additional investigation to better comprehend the disease in the region. Overall, the study provides crucial clinical insights for the diagnosis and treatment of CCC in the Amazon region., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Guevara Moctezuma, Smith Doria, Ortiz, Teixeira de Sousa, Mwangi, do Nascimento Couceiro, Brandão, Guerra, Vale Barbosa Guerra and Barbosa Bemfica Ferreira.)
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- 2023
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7. Early weaning and family characteristics are associated with greater sodium intake in children between 13 and 35 months: BRISA birth cohort.
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De Sousa DR, França AKTDC, Cavalcante MCV, Pereira NO, Fonseca P, and Filho FL
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Children are consuming less healthy foods, and this eating behaviour exposes the child to greater Na intake. The association between family, maternal and child characteristics with Na intake by children aged 13-35 months was evaluated. A study carried out with retrospective data on 1,185 children from the Brisa cohort. The children's dietary Na intake was assessed by a 24-h diet recall survey. Values ≥ 1200 mg were considered excessive intake. The association between Na intake and independent variables was assessed by a three-level logistic hierarchical regression model. Variables with P -value < 0·05 were retained in the model. Most children were male (51·2 %), eutrophic (63·2 %) and not exclusively breast-feeding (EBF) for 6 months (58·4 %). The average Na intake was 925 mg (±410·4). The prevalence of excessive Na intake was 18·5 % and was associated with the variables children of younger mothers (< 20 years old OR = 4·04, 95 % CI 1·64, 9·99; ≥ 20 to < 35 years old OR = 2·48, 95 % CI 1·10, 5·63), having four or more children (OR = 2·51, 95 % CI 1·29, 4·89), lower family income (≥ 1 and < 3 minimum wages OR = 0·60, 95 % CI 0·39, 0·93; ≥ 3 minimum wages OR = 0·50, 95 % CI 0·30, 0·82) and not being EBF until 6 months (OR = 1·64, 95 % CI 1·14, 2·34). The average Na intake of children was higher than the recommendation for adequate intake, pointing to a high consumption of this micronutrient in the first years of life. Excessive Na intake seems to be linked to unfavourable socio-economic conditions. Avoiding early weaning is the only possible intervention in this scenario.
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- 2023
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8. Temporal Changes in Gut Microbiota Composition and Pollen Diet Associated with Colony Weakness of a Stingless Bee.
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Haag KL, Caesar L, da Silveira Regueira-Neto M, de Sousa DR, Montenegro Marcelino V, de Queiroz Balbino V, and Torres Carvalho A
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- Bees, Animals, Diet, Bacteria genetics, Pollen, Pollination, Gastrointestinal Microbiome
- Abstract
Compared to honeybees and bumblebees, the effect of diet on the gut microbiome of Neotropical corbiculate bees such as Melipona spp. is largely unknown. These bees have been managed for centuries, but recently an annual disease is affecting M. quadrifasciata, an endangered species kept exclusively by management in Southern Brazil. Here we report the results of a longitudinal metabarcoding study involving the period of M. quadrifasciata colony weakness, designed to monitor the gut microbiota and diet changes preceding an outbreak. We found increasing amounts of bacteria associated to the gut of forager bees 2 months before the first symptoms have been recorded. Simultaneously, forager bees showed decreasing body weight. The accelerated growth of gut-associated bacteria was uneven among taxa, with Bifidobacteriaceae dominating, and Lactobacillaceae decreasing in relative abundance within the bacterial community. Dominant fungi such as Candida and Starmerella also decreased in numbers, and the stingless bee obligate symbiont Zygosaccharomyces showed the lowest relative abundance during the outbreak period. Such changes were associated with pronounced diet shifts, i.e., the rise of Eucalyptus spp. pollen amount in forager bees' guts. Furthermore, there was a negative correlation between the amount of Eucalyptus pollen in diets and the abundance of some bacterial taxa in the gut-associated microbiota. We conclude that diet and subsequent interactions with the gut microbiome are key environmental components of the annual disease and propose the use of diet supplementation as means to sustain the activity of stingless bee keeping as well as native bee pollination services., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2023
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9. Combined antibodies against internalins A and B proteins have potential application in immunoassay for detection of Listeria monocytogenes .
- Author
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Lopes-Luz L, Silva-Filho E, Mendonça M, Moreira ÂN, Venceslau A, de Sousa DR, Sánchez TG, de Moura RS, Conceição FR, Kipnis A, Stefani MMA, and Bührer-Sékula S
- Abstract
Listeria monocytogenes is a food-borne bacterium that causes listeriosis upon the ingestion of contaminated food. Traditional methods to detect L. monocytogenes require pre-enrichment broths to increase its concentration. To improve the screening of contaminated food and prevent listeriosis outbreaks, rapid, specific and sensitive assays are needed to detect L. monocytogenes. This study developed a prototype lateral flow immunochromatographic assay (LFIA) employing antibodies against L. monocytogenes Internalin A (InlA) and Internalin B (InlB) proteins, that are involved in non-phagocytic cell invasion. The following antibodies were used to capture L. monocytogenes antigenic targets: mouse anti-Internalin A monoclonal antibody (MAb-2D12) conjugated to colloidal gold nanoparticles and a mouse anti-Internalin B polyclonal antibody . This test was able to detect pure L. monocytogenes from culture with a limit of detection (LOD) ranging from 5.9 × 10
3 to 1.5 × 104 CFU/mL. In milk artificially contaminated with L. monocytogenes , the LOD was 1 × 105 CFU/mL. This prototype test discriminated L. monocytogenes from other bacterial species ( Listeria innocua , Enterobacter cloacae , Bacillus cereus ). Results indicate that this LFIA developed using antibodies against L. monocytogenes InlA and InlB proteins is a sensitive and specific tool that can be potentially useful to rapidly detect L. monocytogenes in contaminated food., Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05597-9., Competing Interests: Conflicts of interestThe authors declare that they have no conflict of interest., (© Association of Food Scientists & Technologists (India) 2022, Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)- Published
- 2023
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10. Myocardial Injury in Patients With Acute and Subacute Chagas Disease in the Brazilian Amazon Using Cardiovascular Magnetic Resonance.
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Couceiro KDN, Ortiz JV, Hosannah da Silva E Silva MR, Teixeira de Sousa DR, Andrade RC Jr, Brandão ARJ, de Morais RF, Smith Doria S, Fonseca RA, da Silva PRL, Fernandes F, Guerra MDGVB, Rochitte CE, Ferreira JMBB, and Guerra JAO
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- Adult, Brazil epidemiology, Electrocardiography, Female, Humans, Magnetic Resonance Imaging, Magnetic Resonance Spectroscopy, Male, Middle Aged, Chagas Cardiomyopathy diagnostic imaging, Chagas Cardiomyopathy epidemiology, Chagas Disease complications, Heart Injuries, Ventricular Premature Complexes complications
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Background Chagas disease is a neglected tropical disease that is still considered a global health emergency. In the Amazon region, most of the reports are of acute cases that are associated with oral transmission. This study aimed to evaluate myocardial injury in patients with acute Chagas disease before and after treatment. Methods and Results We evaluated 23 patients with acute Chagas disease in 3 different stages of progression. Group 1 had 12 patients evaluated during the acute phase, at the time of diagnosis, and 1 year after treatment, and Group 2 had 11 patients in the late postacute phase who were evaluated 5.2 years on average after diagnosis and treatment. ECGs with the Selvester score, 24-hour Holter exam, and cardiovascular magnetic resonance imaging were performed. The mean age of the 23 patients was 44.3±18.9 years, and they were mostly men (15/65.24%) from Amazonas state (22/95.6%). In 69.6% (n=16) of the patients, some ECG alterations were found, the most frequent being left anterior fascicular block and ventricular repolarization. In Group 1, the 24-hour Holter exam showed atrial tachycardia in 3 (25%) patients and ventricular extrasystoles in 2 (16.7%) patients. In Group 2, 1 patient had ventricular extrasystoles. Myocardial injury was observed in 7 patients (58.3%) at the acute phase and in 5 (50%) patients at the 1-year follow-up in Group 1 and in 2 (18.2%) patients in Group 2. Conclusions This article describes, for the first time, myocardial injury shown by cardiovascular magnetic resonance imaging in a group of patients with acute Chagas disease and reveals the importance of early detection and follow-up of the cardiac impairment in these patients.
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- 2022
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11. Prediction of genomic breeding values of milk traits in Brazilian Saanen goats.
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de Sousa DR, do Nascimento AV, and Lôbo RNB
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- Animals, Bayes Theorem, Genomics, Genotype, Models, Genetic, Phenotype, Polymorphism, Single Nucleotide, Breeding, Goats genetics, Milk
- Abstract
The study's objective was to compare the genomic prediction ability methods for the traits milk yield, milk composition and somatic cell count of Saanen Brazilian goats. Nine hundred forty goats, genotyped with an Axiom_OviCap (Caprine) panel, Affimetrix customized array with 62,557 single nucleotide polymorphisms (SNPs), were used for the genomic selection analyses. The genomic methods studied to estimate the effects of SNPs and direct genomic values (DGV) were as follows: (a) genomic BLUP (GBLUP), (b) Bayes Cπ and (c) Bayesian Lasso (BLASSO). Estimated breeding values (EBV) and deregressed estimated breeding values (dEBV) were used as response variables for the genomic predictions. The prediction ability was assessed by Pearson's correlation between DGV and response variables (EBV and dEBV). Regression coefficients of the response variables on the DGV were obtained to verify if the genomic predictions were biased. In addition, the mean square error of prediction (MSE) was used as a measure of verification of model fit to the data. The means of prediction accuracy, when EBV was used as a response variable, were 0.68, 0.68 and 0.67 for GBLUP, Bayes Cπ and BLASSO, respectively. With dEBV, the mean prediction accuracy was 0.50 for all models. The averages of the EBV regression coefficients on DGV were 1.08 for all models (GBLUP, Bayes Cπ and BLASSO), higher than those obtained for the regression coefficient of dEBV on DGV, which presented values of 1.05, 1.05 and 1.08 for GBLUP, Bayes Cπ and BLASSO, respectively. None of the methods stood out in terms of prediction ability; however, the GBLUP method was the most appropriate for estimating the DGV, in a slightly more reliable and less biased way, besides presenting the lowest computational cost. In the context of the present study, EBV was the preferred response variables considering the genomic prediction accuracy despite dEBV also presented lower bias., (© 2021 Wiley-VCH GmbH.)
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- 2021
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12. Spherization of red blood cells and platelet margination in COPD patients.
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Zouaoui Boudjeltia K, Kotsalos C, de Sousa DR, Rousseau A, Lelubre C, Sartenaer O, Piagnerelli M, Dohet-Eraly J, Dubois F, Tasiaux N, Chopard B, and Van Meerhaeghe A
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- Aged, Cross-Sectional Studies, Erythrocyte Indices, Female, Humans, Male, Middle Aged, Blood Platelets pathology, Erythrocytes pathology, Pulmonary Disease, Chronic Obstructive blood
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Red blood cells (RBCs) in pathological situations undergo biochemical and conformational changes, leading to alterations in rheology involved in cardiovascular events. The shape of RBCs in volunteers and stable and exacerbated chronic obstructive pulmonary disease (COPD) patients was analyzed. The effects of RBC spherization on platelet transport (displacement in the flow field caused by their interaction with RBCs) were studied in vitro and by numerical simulations. RBC spherization was observed in COPD patients compared with volunteers. In in vitro experiments at a shear rate of 100 s
-1 , treatment of RBCs with neuraminidase induced greater sphericity, which mainly affected platelet aggregates without changing aggregate size. At 400 s-1 , neuraminidase treatment changes both the size of the aggregates and the number of platelet aggregates. Numerical simulations indicated that RBC spherization induces an increase of the platelet mean square displacement, which is traditionally linked to the platelet diffusion coefficient. RBCs of COPD patients are more spherical than healthy volunteers. Experimentally, RBC spherization induces increased platelet transport to the wall. Additional studies are needed to understand the link between the effect of RBCs on platelet transport and the increased cardiovascular events observed in COPD patients., (© 2020 New York Academy of Sciences.)- Published
- 2021
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13. Histomorphometric changes of the fore-stomach of lambs fed with diets containing spineless cactus genotypes resistant to Dactylopius sp.
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da Silva TGP, Batista ÂMV, Guim A, da Silva VA Jr, de Carvalho FFR, de Barros MEG, de Sousa DR, and da Silva SMC
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- Animal Feed analysis, Animal Nutritional Physiological Phenomena, Animals, Antibiosis, Hemiptera physiology, Male, Cactaceae chemistry, Diet veterinary, Rumen physiology, Sheep, Domestic physiology
- Abstract
The histomorphometric parameters of the fore-stomach epithelium of lambs fed with spineless cactus genotypes resistant to Dactylopius sp. were evaluated. Thirty-two lambs (23.0 ± 2.06 kg body weight) were distributed in a completely randomized design with four treatments and eight replications. The treatments consisted of the base diet and diets in which part of the elephant grass hay and all ground corn was replaced by the Miúda, IPA-Sertânia, or Orelha de Elefante Mexicana (OEM) spineless cacti. The keratin layers of the ruminal epithelium of the animals consuming the spineless cacti Miúda and OEM presented greater thickening relative to the control diet: 47.31, 41.30, and 25.81 μm, respectively. The heights of the ruminal papillae were higher in the animals that were fed with the OEM spineless cactus. The Miúda spineless cactus caused an enlargement in the keratinized layer of the reticulum epithelium, as well as a decrease in the thickness of the non-keratinized layers. The diet containing OEM spineless cactus resulted in greater thickening of the keratin layer of the omasal epithelium and decreased thickness of the non-keratinized layers. The spineless cacti Miúda and OEM changed the morphology of the fore-stomach epithelium and increased the dry matter intake and weight gain of lambs.
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- 2020
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14. High frequency of CYP337B3 gene associated with control failures of Helicoverpa armigera with pyrethroid insecticides in Brazil.
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Durigan MR, Corrêa AS, Pereira RM, Leite NA, Amado D, de Sousa DR, and Omoto C
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- Animals, Brazil, Larva drug effects, Larva genetics, Moths genetics, Cytochrome P-450 Enzyme System genetics, Insect Proteins genetics, Insecticide Resistance genetics, Insecticides toxicity, Moths drug effects, Nitriles toxicity, Pyrethrins toxicity
- Abstract
Control failures with the use of pyrethroid insecticides have been reported frequently for populations of Helicoverpa armigera (Hübner) in Brazil, since its detection in 2013. Here, we confirmed and investigated the metabolic mechanisms of pyrethroid resistance in H. armigera populations from Brazil. Mortality of H. armigera populations was lower than 50% at the highest dose (10μg a.i./3rd instar larva) of the pyrethroids deltamethrin and fenvalerate in dose-response bioassays. Very low mortality (10 to 40%) was obtained at a diagnostic dose of 10μg a.i./larva for each pyrethroid in H. armigera populations collected from different agricultural regions in Brazil, from 2013 to 2016. In synergist bioassays, when larvae were treated with PBO synergist, the mortality of all populations tested was 100%. The frequency of the cytochrome P450 CYP337B3 gene was above 0.95 in all populations of H. armigera. We found only fourteen heterozygous H. armigera out of 497 individuals tested for this gene subfamily. Our results indicated that H. armigera populations from Brazil have different degrees of susceptibility to deltamethrin and fenvalerate, but all populations can be considered tolerant to pyrethroid insecticides. The chimeric P450 CYP337B3 enzyme is one of the main mechanisms of pyrethroid resistance in Brazilian H. armigera populations., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2017
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15. A physical description of the adhesion and aggregation of platelets.
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Chopard B, de Sousa DR, Lätt J, Mountrakis L, Dubois F, Yourassowsky C, Van Antwerpen P, Eker O, Vanhamme L, Perez-Morga D, Courbebaisse G, Lorenz E, Hoekstra AG, and Boudjeltia KZ
- Abstract
The early stages of clot formation in blood vessels involve platelet adhesion-aggregation. Although these mechanisms have been extensively studied, gaps in their understanding still persist. We have performed detailed in vitro experiments, using the well-known Impact-R device, and developed a numerical model to better describe and understand this phenomenon. Unlike previous studies, we took into account the differential role of pre-activated and non-activated platelets, as well as the three-dimensional nature of the aggregation process. Our investigation reveals that blood albumin is a major parameter limiting platelet aggregate formation in our experiment. Simulations are in very good agreement with observations and provide quantitative estimates of the adhesion and aggregation rates that are hard to measure experimentally. They also provide a value of the effective diffusion of platelets in blood subject to the shear rate produced by the Impact-R., Competing Interests: We declare we have no competing interests.
- Published
- 2017
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16. Does the gravity orientation of saccular aneurysms influence hemodynamics? An experimental study with and without flow diverter stent.
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Chodzyński KJ, Eker OF, Vanrossomme AE, de Sousa DR, Coussement G, Vanhamme L, Dubois F, Bonafé A, Chopard B, Courbebaisse G, and Zouaoui Boudjeltia K
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- Brain blood supply, Brain diagnostic imaging, Brain physiology, Cerebrovascular Circulation, Erythrocytes physiology, Female, Gravitation, Hemodynamics, Humans, Intracranial Aneurysm diagnostic imaging, Intracranial Aneurysm therapy, Magnetic Resonance Imaging, Male, Intracranial Aneurysm physiopathology, Stents
- Abstract
Most intracranial aneurysms morphologic studies focused on characterization of size, location, aspect ratio, relationship to the surrounding vasculature and hemodynamics. However, the spatial orientation with respect to the gravity direction has not been taken into account although it could trigger various hemodynamic conditions. The present work addresses this possibility. It was divided in two parts: 1) the orientations of 18, 3D time-of-flight MRI (3D TOF MRI), scans of saccular aneurysms were analyzed. This investigation suggested that there was no privileged orientation for cerebral aneurysms. The aneurysms were oriented in the brain as follows: 9 - down, 9 - up; 11 - right, 7 - left; 6 - front, 12 - back. 2) Based on these results, subsidiary in vitro experiments were performed, analyzing the behavior of red blood cells (RBCs) within a silicone model of aneurysm before and after flow diverter stent (FDS) deployment in the parent vessel. These experiments used a test bench that reproduces physiological pulsatile flow conditions for two orientations: an aneurysm sack pointing either up (opposite to gravitational force) and down (along the gravitational force). The results showed that the orientation of an aneurysm significantly affects the intra-aneurysmal RBCs behavior after stenting, and therefore that gravity can affect the intra-aneurysm behavior of RBCs. This suggests that the patient׳s aneurysm orientation could impact the outcome of the FDS treatment. The implementation of this effect in patient-specific numerical and preoperative decision support techniques could contribute to better understand the intrasaccular biological and hemodynamic events induced by FDS., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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17. Metabolic syndrome, diet and exercise.
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De Sousa SM Dr and Norman RJ Prof
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- Diet, Exercise, Female, Humans, Hydroxymethylglutaryl-CoA Reductase Inhibitors therapeutic use, Hyperlipidemias complications, Hyperlipidemias therapy, Hypertension complications, Hypertension therapy, Metabolic Syndrome complications, Metformin therapeutic use, Obesity complications, Patient Compliance, Polycystic Ovary Syndrome complications, Weight Reduction Programs, Bariatric Surgery, Diet Therapy, Exercise Therapy, Hypoglycemic Agents therapeutic use, Metabolic Syndrome therapy, Obesity therapy, Polycystic Ovary Syndrome therapy
- Abstract
Polycystic ovary syndrome (PCOS) is associated with a range of metabolic complications including insulin resistance (IR), obesity, dyslipidaemia, hypertension, obstructive sleep apnoea (OSA) and non-alcoholic fatty liver disease. These compound risks result in a high prevalence of metabolic syndrome and possibly increased cardiovascular (CV) disease. As the cardiometabolic risk of PCOS is shared amongst the different diagnostic systems, all women with PCOS should undergo metabolic surveillance though the precise approach differs between guidelines. Lifestyle interventions consisting of increased physical activity and caloric restriction have been shown to improve both metabolic and reproductive outcomes. Pharmacotherapy and bariatric surgery may be considered in resistant metabolic disease. Issues requiring further research include the natural history of PCOS-associated metabolic disease, absolute CV risk and comparative efficacy of lifestyle interventions., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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18. Hemodynamic numerical simulations of the disturbance due to intracoronary flow measurements by a Doppler guide wire.
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Chodzyński KJ, Gremmo S, Eker OF, Lalmand J, Aminian A, de Sousa DR, Boudjeltia KZ, and Coussement G
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- Algorithms, Coronary Angiography, Coronary Vessels diagnostic imaging, Hydrodynamics, Imaging, Three-Dimensional, Coronary Vessels physiology, Hemodynamics, Models, Cardiovascular, Pulse Wave Analysis instrumentation
- Abstract
Background: Since hemodynamics plays a key role in the development and evolution of cardiovascular pathologies, physician's decision must be based on proper monitoring of relevant physiological flow quantities., Methods: A numerical analysis of the error introduced by an intravascular Doppler guide wire on the peak velocity measurements has been carried out. The effect of probe misalignment (±10°) with respect to the vessel axis was investigated. Numerical simulations were performed on a realistic 3D geometry, reconstructed from coronary angiography images. Furthermore, instead of using Poiseuille or Womersley approximations, the unsteady pulsatile inlet boundary condition has been calculated from experimental peak-velocity measurements inside the vessel through a new approach based on an iterative Newton's algorithm., Results: The results show that the presence of the guide modifies significantly both the maximum velocity and the peak position in the section plane; the difference is between 6 and 17 % of the maximum measured velocity depending on the distance from the probe tip and the instantaneous vessel flow rate. Furthermore, a misalignment of the probe may lead to a wrong estimation of the peak velocity with an error up to 10 % depending on the probe orientation angle., Conclusions: The Doppler probe does affect the maximum velocity and its position during intravascular Doppler measurements. Moreover, the Doppler-probe-wire sampling volume at 5.2 and 10 mm far from the probe tip is not sufficient to prevent its influence on the measurement. This should be taken into account in clinical practice by physicians during intravascular Doppler quantification. The new numerical approach used in this work could potentially be helpful in future numerical simulations to set plausible inlet boundary conditions.
- Published
- 2016
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19. An in vitro test bench reproducing coronary blood flow signals.
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Chodzyński KJ, Boudjeltia KZ, Lalmand J, Aminian A, Vanhamme L, de Sousa DR, Gremmo S, Bricteux L, Renotte C, Courbebaisse G, and Coussement G
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- Adult, Blood Flow Velocity, Coronary Vessels diagnostic imaging, Female, Fourier Analysis, Humans, Hydrodynamics, Male, Middle Aged, Models, Biological, Pulsatile Flow, Reproducibility of Results, Tomography, X-Ray Computed, Coronary Vessels physiology, Signal Processing, Computer-Assisted
- Abstract
Background: It is a known fact that blood flow pattern and more specifically the pulsatile time variation of shear stress on the vascular wall play a key role in atherogenesis. The paper presents the conception, the building and the control of a new in vitro test bench that mimics the pulsatile flows behavior based on in vivo measurements., Methods: An in vitro cardiovascular simulator is alimented with in vivo constraints upstream and provided with further post-processing analysis downstream in order to mimic the pulsatile in vivo blood flow quantities. This real-time controlled system is designed to perform real pulsatile in vivo blood flow signals to study endothelial cells' behavior under near physiological environment. The system is based on an internal model controller and a proportional-integral controller that controls a linear motor with customized piston pump, two proportional-integral controllers that control the mean flow rate and temperature of the medium. This configuration enables to mimic any resulting blood flow rate patterns between 40 and 700 ml/min. In order to feed the system with reliable periodic flow quantities in vivo measurements were performed. Data from five patients (1 female, 4 males; ages 44-63) were filtered and post-processed using the Newtonian Womersley's solution. These resulting flow signals were compared with 2D axisymmetric, numerical simulation using a Carreau non-Newtonian model to validate the approximation of a Newtonian behavior., Results: This in vitro test bench reproduces the measured flow rate time evolution and the complexity of in vivo hemodynamic signals within the accuracy of the relative error below 5%., Conclusions: This post-processing method is compatible with any real complex in vivo signal and demonstrates the heterogeneity of pulsatile patterns in coronary arteries among of different patients. The comparison between analytical and numerical solution demonstrate the fair quality of the Newtonian Womersley's approximation. Therefore, Womersley's solution was used to calculate input flow rate for the in vitro test bench.
- Published
- 2015
- Full Text
- View/download PDF
20. Toward prevention of cowdriosis.
- Author
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Pedregal A, de Sousa DR, Nguyen HN, das Neves EA, Lowagie S, Marique T, Kagye N, Guerra IT, Kamba Y, Totte P, Vachiéry N, Lefrançois T, Martinez D, Yourassowsky C, Callens N, Monnom O, Dubois F, and Wérenne J
- Subjects
- Animals, Cattle, Humans, Hybrid Cells, Bacterial Vaccines therapeutic use, Ehrlichiosis prevention & control, Interferons metabolism
- Abstract
Mass production of Ehrlichia ruminantium variants from different regions of sub-Saharan Africa is one of the difficulties that must be overcome in producing a heartwater vaccine. Vaccine productivity can be limited by endogenous induction of interferon (IFN), which inhibits the propagation of Ehrlichia ruminantium (ER) in cell culture. Different kinds of endothelial cells, in which ER multiply efficiently, could be grown in a scalable way in VueLife Teflon bags on Cytodex 3 microcarriers where bead-to-bead transfer of cells occurs. The digital holographic microscope designed at the Université Libre de Bruxelles allows detection of the most appropriate time to harvest intracellular microorganisms for vaccine production.
- Published
- 2008
- Full Text
- View/download PDF
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