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Introduction: Preventive care practices are a challenge in community care. This study examined hantavirus preventive practices and their relationship with personal and social factors, lifestyle, and cultural beliefs., Method: An explanatory sequential mixed methods design, guided by Leininger's Theory of Culture Care Diversity and Universality, was used in two phases: (a) a cross-sectional relational design ( n = 109) and (b) ethnonursing research ( n = 30), in an endemic community in Panama. Univariate and bivariate analyses were used to analyze the quantitative data, whereas the Leininger's analysis model was used to analyze the qualitative data., Results: In the quantitative phase, the most frequent preventive practice was household hygiene, and the least frequent was vector control. Two of the eight preventive practices were associated with personal factors and two were associated with social factors. In the qualitative phase, lifestyle, beliefs, and context were found to influence the adoption of hantavirus preventive practices and help explain the quantitative findings., Discussion: Knowledge and understanding of the social and cultural contexts are essential for hantavirus prevention., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

We searched for evidence of knockdown resistance (kdr) mutations in the voltage-gated sodium channel gene of Aedes aegypti (Linnaeus) (Diptera: Culicidae) and Aedes albopictus (Skuse) (Diptera: Culicidae) mosquitoes from Panama. Conventional PCR was performed on 469 Ae. aegypti and 349 Ae. albopictus. We did not discover kdr mutations in Ae. albopictus, but 2 nonsynonymous kdr mutations, V1016I (found in 101 mosquitoes) and F1534C (found in 29 of the mosquitoes with the V1016I), were detected in Ae. aegypti. These kdr mutations were present in all specimens that were successfully sequenced for both IIS5-S6 and IIIS6 regions, which included samples collected from 8 of the 10 provinces of Panama. No other kdr mutations were found in Ae. aegypti, including V1016G, which has already been reported in Panama. Findings suggest that the V1016I-F1534C variant is prevalent in Panama, which might be related to the introduction and passive movement of mosquitoes as part of the used-tire trade. However, we cannot rule out the possibility that selection on de novo replacement of kdr mutations also partially explains the widespread distribution pattern of these mutations. These 2 ecological and evolutionary processes are not mutually exclusive, though, as they can occur in tandem. Research in Panama needs to calculate the genotypic and allelic frequencies of kdr alleles in local Ae. aegypti populations and to test whether some combinations confer phenotypic resistance or not. Finally, future studies will have to track the introduction and spreading of new kdr mutations in both Aedes species., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Cutaneous pili migrans is a rare and interesting dermatological condition characterized by embedding a hair or its fragment in the epidermis or superficial dermis, sometimes leading to pain and a serpiginous rash. We present a 28-year-old male who came to the clinic concerned about the sudden onset of pain in his foot over 10 hours. Upon meticulous physical examination, we found a white hair embedded in the skin of the fifth toe of his left foot, which the patient immediately recognized as hair from his dog. Upon removal of the hair, the pain immediately resolved. We believe our case represents the first reported case in Panama, the second in Latin America, and the second associated with dog hair. We anticipate that more cases related to animal hairs will be reported in the coming years due to the increasing popularity of pets in this century., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Salazar et al.)

Snakebites still constitute a significant public health problem in developing countries and are considered a neglected tropical condition by the WHO. Snake accidents are associated with substantial morbidity and mortality and may produce secondary complications, such as severe infections. The objective of this systematic review was to determine the prevalence of snakebite infections and characterize the bacteria isolated from these infections. A systematic literature review in five databases was carried out to assess the prevalence of snakebite infection. A meta-analysis was performed using a random-effects model to calculate the pooled prevalence and 95% CIs. Cochran's Q test and the I2 statistic were used to assess between-study heterogeneity. The pooled prevalence of infection due to snakebite was 27.0% (95% CI: 22.0-32.0%), with high heterogeneity among studies (I2 = 99.7%). The prevalence was higher in Asia (32%) than in the Americas (21%). Snakebite infections required surgical interventions in 68% (95% CI: 37.0-98.0%). The leading group of pathogens identified corresponded to Gram-negative bacteria (63%), particularly Morganella morganii (32%), but also, Gram-positive cocci (40%), especially Enterococcus spp. (23%) and Staphylococcus aureus (15%). However, multiple other pathogens, including anaerobes, were found. A high prevalence of snakebite-associated infection has been described, primarily due to M. morganii, with the corresponding implications for empirical therapy. Rational use of antimicrobials is recommended, and this should guide initial empirical treatment. Moreover, isolation and identification of the possible bacteria present in snakebite wounds is recommended in all cases to confirm or rule out associated infection.

Introduction: Norovirus infection is a common cause of acute gastroenteritis (AGE). Surveillance activities are important to aid investigation into effective norovirus control strategies, including vaccination. Here, we report ancillary findings related to the incidence, prevalence, and etiology of AGE caused by norovirus in Panama after adjustment of study methodology to comply with national coronavirus disease 2019 (COVID-19) mandates., Methods: In January 2020, children aged <2 years began enrolling into an epidemiological study in Panama to estimate the burden of norovirus in preparation for evaluating upcoming prevention strategies. This included an observational, longitudinal, community-based AGE surveillance study and a hospital-based AGE surveillance study. For the longitudinal study, healthy children aged 5-18 months were enrolled from January 6 through March 23, 2020, with a follow-up of approximately 6 months. The last participant was contacted on September 23, 2020. For the hospital-based study, starting on January 21, 2020, children aged <2 years who were admitted to the Hospital del Niño Dr. José Renán Esquivel in Panama City due to AGE were evaluated. The last sample was collected on September 29, 2020. Collected stool samples were tested for norovirus as well as astrovirus, sapovirus, and various enteropathogens. Unfortunately, this study was disrupted by the subsequent implementation of disease transmission control procedures for the COVID-19 pandemic, and the study methodology was revised to comply with COVID-19 mandates., Results: In the longitudinal surveillance cohort [ N  = 400 (Chiriquí, n  = 239; Panama, n  = 161)], a total of 185 AGE episodes were documented (Chiriquí, n  = 85; Panama, n  = 100) resulting in an overall AGE incidence of 11.6 (95% CI: 9.99-13.4) episodes per 100 child-months. The norovirus-related AGE incidence was 0.3 (95% CI: 0.10-0.73) episodes per 100 child-months (5/185 AGE episodes) and the prevalence of norovirus was 4.6% (13/282 stool samples collected). In the hospital-based surveillance cohort, at least one pathogen was detected in 50% of samples (44/88 stool samples collected) and norovirus prevalence was 6.8% (6/88 stool samples collected)., Discussion: This report demonstrates how the occurrence of the COVID-19 pandemic hindered the conduct of clinical trials. However, this also created unique research opportunities to investigate the potential impact of pandemic control measures on the etiology of infectious diarrheal disease., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: JW is a permanent employee of Takeda Vaccines. RD, MH-H, LA, ZC-B, LD, TL, XS, and BM received funding for the study from Takeda Vaccines to support the costs of the trial., (© 2024 DeAntonio, Hess-Holtz, Abrego, Capitan-Barrios, Donoso, De León, Sáez Llorens, Moreno and Weil.)

Tree life history strategies are correlated with functional plant traits, such as wood density, moisture content, bark thickness, and nitrogen content; these traits affect the nutrients available to xylophagous insects. Cerambycid beetles feed on substrates that vary in these traits, but little is known about how they affect community composition. The goal of this project is to explore the community composition of two cerambycid subfamilies (Cerambycinae and Lamiinae) according to the wood traits in the wood they eat. In a salvage project conducted adjacent to the Panama Canal, trees were felled and exposed to Cerambycidae for oviposition. Disks from branches of differing thickness from the same plant individuals were used to calculate wood density, moisture content, and bark thickness in the field; nitrogen data were acquired offsite. Thick and thin branches tended to differ in wood trait values; therefore, data were analyzed separately in subsequent analyses. In thin branches, cerambycid abundance and species richness were higher in samples with less dense, moister wood, and thicker bark. Thick branches showed similar trends, but the wood traits accounted for little variability in beetle abundance or species richness. There were no significant regressions between beetle data and nitrogen. Cerambycines emerged more slowly, and from denser, drier wood, than lamiines. Cerambycines might be more drought-tolerant than lamiines, and therefore more resistant to the longer, more severe dry seasons that are predicted to occur due to climate change.

Soil microbes impact plant community structure and diversity through plant-soil feedbacks. However, linking the relative abundance of plant pathogens and mutualists to differential plant recruitment remains challenging. Here, we tested for microbial mediation of pairwise feedback using a reciprocal transplant experiment in a lowland tropical forest in Panama paired with amplicon sequencing of soil and roots. We found evidence that plant species identity alters the microbial community, and these changes in microbial composition alter subsequent growth and survival of conspecific plants. We also found that greater community dissimilarity between species in their arbuscular mycorrhizal and nonpathogenic fungi predicted increased positive feedback. Finally, we identified specific microbial taxa across our target functional groups that differentially accumulated under conspecific settings. Collectively, these findings clarify how soil pathogens and mutualists mediate net feedback effects on plant recruitment, with implications for management and restoration., (© 2023 The Authors. Ecology published by Wiley Periodicals LLC on behalf of The Ecological Society of America.)

Objective: It is necessary to establish the evolution that the pandemic has had in Panama by weeks and months and to clearly establish the existence of surges or peaks, according to cases and deaths and the relationship with age groups., Methodology: We conducted a retrospective cohort study of all confirmed COVID-19 cases reported by the Ministry of Health of Panama during the first 3 years of the epidemic (March 9, 2020, March 11, 2023). All cases were obtained from information provided by the Ministry of Health. We obtained daily information of the population at the national level reported as new cases, deaths, admission to hospitals, admission to intensive care units and by age groups. The information is classified by epidemiological week and by month from the diagnosis of the first case until March 2023., Results: During the three years of the study, 1,032,316 cases of COVID-19 were registered in the Republic of Panama, and the number of deaths reported was 8,621, for a fatality rate of 0.83 % throughout that period. The number of deaths decreased over the 3 years of the pandemic; however, similar to the cases, there were periods of surges (peaks) per year in June/July and in December/January . The lethality progressively increased according to the age of the affected patients. During the first year, the lethality in those under 20 years of age was 0.05 %, and in those over 80 years old, it was 17.54 %. This pattern was maintained during the second year; however, there was a large decrease in all age groups., Conclusion: the highest lethality rate in Panama occurred in the first year of the pandemic, with a great decrease in the third year; the impact of lethality is proportional to the age of the individual, with a high possibility of death in those over 80 years of age. During each pandemic year, there are two peaks (surges of new cases and deaths) per year, which are important times to take into account to generate strategies aimed at reducing the impact., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:PAULINO VIGIL-DE GRACIA reports was provided by Social Security Fund, Panama. Paulino Vigil-De Gracia reports a relationship with Social Security Fund, Panama that includes: employment. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Many people from poverty-stricken countries are migrating across South and Central America to reach the México-United States border, a movement exacerbated by the COVID-19 pandemic. Migrant people who begin their northbound journey in South America must transit across a significant geographic bottleneck, the Darién Gap, a mountainous rainforest region between Colombia and Panama. Most migrant people crossing this region originate from Cuba, Haiti, and Venezuela. Other people reach the shores of South American countries from west and central Africa or central and southeastern Asia and continue to the Darién Gap. Poverty and violence drive families with children to flee their homes and endure incalculable risks in their path. Children traveling with their families or as unaccompanied minors across the Darién Gap are exposed to life-threatening situations and human rights violations, including abuse, exploitation, malnourishment, and limited access to medical care. In addition to experiencing untreated medical illnesses, children experience mental health disorders during migration and after they reach their destination as a result of victimization and adverse traumatic experiences. Therefore, providing migrants, especially children, with rapid medical screenings and mental health support when they arrive at their destination is critical to reduce health inequities. Furthermore, making these interventions available during their transit and ensuring their safety may prevent further human rights abuses in children and families. Latin American governments must address the ongoing humanitarian crisis endured by migrants throughout their migratory path by offering access to essential healthcare services and safeguarding the rights and security of children and vulnerable groups.

Increased activation and proliferation of T lymphocytes plays an essential role in the development of chronic inflammation and autoimmune diseases. Currently used immunosuppressive drugs often do not provide long-lasting relief of symptoms and show a gradual loss of efficacy over time, and are accompanied by various side effects. Therefore, novel immunosuppressive lead substances are needed. For this purpose, an in-house library consisting of 600 extracts of plants from Panama was screened for inhibition of human T lymphocyte proliferation. As one of the hits, an ethyl acetate extract from the aerial parts of Hyptis brachiata (Lamiaceae) exhibited strong inhibitory effects. Subsequent investigation resulted in the isolation of seven aryltetralin lignans, five arylnaphthalene lignans, two flavonoids, three triterpenes, and cinnamyl cinnamate. Aryltetralin lignans inhibited T lymphocyte proliferation in a concentration-dependent manner without induction of apoptosis. No relevant inhibition was observed for the arylnaphthalene lignans, flavonoids, and triterpenes. Additional cell cycle arrest investigations revealed that isolated aryltetralin lignans potently inhibited cell division in G2/M phase similarly to podophyllotoxin. Multifluorescence panel analyses of the extract also showed weak suppressive effects on the production of IL-2 and TNF-α. Therefore, preparations made out of H. brachiata could be further explored as an interesting herbal alternative in the treatment of autoimmune diseases., Competing Interests: Conflict of interest statement The authors declare no competing interests., (Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Due to their particular water absorption capacity, hydrogels are the most widely used scaffolds in biomedical studies to regenerate damaged tissue. Hydrogels can be used in tissue engineering to design scaffolds for three-dimensional cell culture, providing a novel alternative to the traditional two-dimensional cell culture as hydrogels have a three-dimensional biomimetic structure. This material property is crucial in regenerative medicine, especially for the nervous system, since it is a highly complex and delicate structure. Hydrogels can move quickly within the human body without physically disturbing the environment and possess essential biocompatible properties, as well as the ability to form a mimetic scaffold in situ . Therefore, hydrogels are perfect candidates for biomedical applications. Hydrogels represent a potential alternative to regenerating tissue lost after removing a brain tumor and/or brain injuries. This reason presents them as an exciting alternative to highly complex human physiological problems, such as injuries to the central nervous system and neurodegenerative disease., Competing Interests: DR was supported by the SENACYT, Panamá: (Grant Nos. FID17-078 and FID18-042), PFID-INF-2020-22 and IDDS22-09; SENACYT, Panamá, supported JR: (Grant No. FID18-042). JM was supported by SENACYT, Panamá: (Grant Nos. APY19-009 and MINBUZA-2020.926889) from the Department of European Integration, Netherlands. The authors declare that there are no conflicts of interest., (Copyright © 2022 Andrea Revete et al.)

Objective: To describe reported changes in sexual behaviours, including virtual sex (sexting and cybersex), and access to HIV/STI testing and care during COVID-19 measures in Panama., Methods: We conducted an online cross-sectional survey from 8 August to 12 September 2020 among adults (≥18 years) residing in Panama. Participants were recruited through social media. Questions included demographics, access to HIV/STI testing and HIV care, and sexual behaviours 3 months before COVID-19 social distancing measures and during social distancing measures (COVID-19 measures). Logistic regression was used to identify associations between variables and behavioural changes., Results: We recruited 960 participants; 526 (54.8%) identified as cis-women, 366 (38.1%) cis-men and 68 (7.1%) non-binary or another gender. The median age was 28 years (IQR: 23-37 years), and 531 of 957 (55.5%) were of mixed ethnicity (mixed Indigenous/European/Afro-descendant ancestry). Before COVID-19 measures, virtual sex was reported by 38.5% (181 of 470) of cis-women, 58.4% (184 of 315) cis-men and 45.0% (27 of 60) non-binary participants. During COVID-19 measures, virtual sex increased among 17.2% of cis-women, 24.7% cis-men and 8.9% non-binary participants. During COVID-19 measures, 230 of 800 (28.8%) participants reported decreased casual sex compared with pre-COVID-19 measures. Compared with pre-COVID-19 measures, decreased casual sex was reported more frequently during COVID-19 measures by cis-men compared with cis-women (39.2% vs 22.9%, urban/rural adjusted OR (AOR)=2.17, 95% CI 1.57 to 3.01), and by Afro-descendant compared with participants of mixed ethnicity (40.0% vs 29.8%, AOR=1.78, 95% CI 1.07 to 2.94). Compared with no change in virtual sex (16.8%), increased virtual sex (38.5%, AOR=1.78, 95% CI 1.10 to 2.88) and decreased virtual sex (86.7%, AOR=16.53, 95% CI 7.74 to 35.27) were associated with decreased casual sex encounters. During COVID-19 measures, HIV/STI testing could not be obtained by 58.0% (58 of 100) of the participants who needed a test, and interrupted HIV care was reported by 53.3% (8 of 15) of participants living with HIV., Conclusions: COVID-19 measures in Panama were associated with a decrease in casual sex among cis-men and Afro-descendant people, while access to HIV/STI testing and care was seriously disrupted., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

Rapid rise of population migration is a defining feature of the 21st century due to the impact of climate change, political instability, and socioeconomic downturn. Over the last decade, an increasing number of migrant peoples travel across the Americas to reach the United States seeking asylum or cross the border undocumented in search of economic opportunities. In this journey, migrant people experience violations of their human rights, hunger, illness, violence and have limited access to medical care. In the 'Divine Comedy', the Italian poet Dante Alighieri depicts his allegorical pilgrimage across Hell and Purgatory to reach Paradise. More than 700 years after its publication, Dante's poem speaks to the present time and the perilious journey of migrant peoples to reach safehavens. By exploring the depths and heights of the human condition, Dante's struggles resonate with the multiple barriers and the unfathomable experiences faced by migrant peoples in transit across South, Central, and North America to reach the United States. Ensuring the safety of migrant peoples across the Americas and elsewhere, and attending to their health needs during their migratory paths represent modern priorities to reduce social injustices and achieving health equity., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Mayaro virus (MAYV) manipulates cell machinery to successfully replicate. Thus, identifying host proteins implicated in MAYV replication represents an opportunity to discover potential antiviral targets. PIM kinases are enzymes that regulate essential cell functions and also appear to be critical factors in the replication of certain viruses. In this study we explored the consequences of PIM kinase inhibition in the replication of MAYV and other arboviruses. Cytopathic effects or viral titers in samples from MAYV-, Chikungunya-, Una- or Zika-infected cells treated with PIM kinase inhibitors were evaluated using an inverted microscope or plaque-forming assays. The expression of viral proteins E1 and nsP1 in MAYV-infected cells was assessed using an immunofluorescence confocal microscope or Western blot. Our results revealed that PIM kinase inhibition partially prevented MAYV-induced cell damage and also promoted a decrease in viral titers for MAYV, UNAV and ZIKV. The inhibitory effect of PIM kinase blocking was observed for each of the MAYV strains tested and also occurred as late as 8 h post infection (hpi). Finally, PIM kinase inhibition suppressed the expression of MAYV E1 and nsP1 proteins. Taken together, these findings suggest that PIM kinases could represent an antiviral target for MAYV and other arboviruses.

Purpose of Review: Review international efforts to build a global public health initiative focused on toxoplasmosis with spillover benefits to save lives, sight, cognition and motor function benefiting maternal and child health., Recent Findings: Multiple countries' efforts to eliminate toxoplasmosis demonstrate progress and context for this review and new work., Summary: Problems with potential solutions proposed include accessibility of accurate, inexpensive diagnostic testing, pre-natal screening and facilitating tools, missed and delayed neonatal diagnosis, restricted access, high costs, delays in obtaining medicines emergently, delayed insurance pre-approvals and high medicare copays taking considerable physician time and effort, harmful shortcuts being taken in methods to prepare medicines in settings where access is restricted, reluctance to perform ventriculoperitoneal shunts promptly when needed without recognition of potential benefit, access to resources for care, especially for marginalized populations, and limited use of recent advances in management of neurologic and retinal disease which can lead to good outcomes., Supplementary Information: The online version contains supplementary material available at 10.1007/s40124-022-00268-x., Competing Interests: Conflict of Interest/Competing Interests There are no other disclosures and no other competing interests., (© The Author(s) 2022.)

Objectives: To determine the prevalence and risk factors of genital Chlamydia trachomatis (CT) among school-going sexually experienced male and female adolescents in Panama., Methods: We conducted two multisite cross-sectional studies using two-stage cluster sampling to select adolescents aged 14-19 years attending urban public high schools (URB) in Panama City, San Miguelito, Colón and Panama Oeste from 2015 to 2018, and in the rural Indigenous Comarca Ngäbe-Buglé (CNB) from July-November 2018. CT testing was performed by real-time PCR on urine samples. Random-effects logistic regression accounting for sample clustering was used to identify risk factors., Results: We enrolled 3166 participants (54.3% females), median age 17 years (IQR: 15.9-18.1), with no difference by sex. Sexual experience was reported by 1954 (61.7%) participants. Combined CT prevalence was 15.8% (95% CI: 14.2 to 17.4), with no significant differences by region (URB=16.5%, 95% CI: 14.7% to 18.6%; CNB=13.6%, 95% CI: 10.9% to 16.8%; p=0.12). In an age-and-region-adjusted analysis, CT prevalence was higher among female participants compared with males (21.6% vs 9.1%, adjusted OR (AOR)=2.87, 95% CI: 1.62 to 5.10). Among sexually experienced females, CT prevalence was higher among those who reported ≥3 lifetime sex partners compared with one partner (33.5% vs 15.3%, AOR=2.20, 95% CI: 1.09 to 4.07); and among those reporting at least one pregnancy compared with nulligravidae participants (30.9% vs 13.8%, AOR=1.89, 95% CI: 1.05 to 3.43). In unadjusted analyses among males, CT was associated with older age (11.5% among those aged 18-19 years vs 3.4% among those aged 14-15 years, OR=3.69, 95% CI: 1.10 to 12.33)., Conclusions: We report high CT prevalence among sexually experienced, school-going adolescents in Panama. Female adolescents, particularly those with multiple sex partners and a history of pregnancy, were at highest risk. Adolescent-targeted CT screening should be implemented in Panama. Additionally, evidence-based comprehensive sexuality education will be imperative., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

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.

The present research aimed to evaluate the antibacterial activity of volatile organic compounds (VOCs) produced by octocoral-associated bacteria Bacillus sp. BO53 and Pseudoalteromonas sp. GA327. The volatilome bioactivity of both bacteria species was evaluated against human pathogenic antibiotic-resistant bacteria, methicillin-resistant Staphylococcus aureus , Acinetobacter baumanni , and Pseudomonas aeruginosa . In this regard, the in vitro tests showed that Bacillus sp. BO53 VOCs inhibited the growth of P. aeruginosa and reduced the growth of S. aureus and A. baumanni . Furthermore, Pseudoalteromonas sp. GA327 strongly inhibited the growth of A. baumanni , and P. aeruginosa . VOCs were analyzed by headspace solid-phase microextraction (HS-SPME) joined to gas chromatography-mass spectrometry (GC-MS) methodology. Nineteen VOCs were identified, where 5-acetyl-2-methylpyridine, 2-butanone, and 2-nonanone were the major compounds identified on Bacillus sp. BO53 VOCs; while 1-pentanol, 2-butanone, and butyl formate were the primary volatile compounds detected in Pseudoalteromonas sp. GA327. We proposed that the observed bioactivity is mainly due to the efficient inhibitory biochemical mechanisms of alcohols and ketones upon antibiotic-resistant bacteria. This is the first report which describes the antibacterial activity of VOCs emitted by octocoral-associated bacteria.

Background: Adrenal masses are commonly encountered in clinical practice, many of whom are incidental. Identifying malignancy, and excess hormone production is essential for appropriate management. Biochemical workup and imaging tests (dedicated adrenal CT and/or MRI) are used to determine the likelihood of excessive hormone function and malignancy, respectively. However, imaging cannot provide information about function and biochemical workup cannot localize the source. Furthermore, in primary aldosteronism, adrenal vein sampling, the gold standard for lateralization, has important limitations such as the technical expertise required, the elevated costs, and potential complications. Over the last decades, there has been a renewed interest in alternative noninvasive imaging techniques that provide information about adrenal function without the need for invasive procedures. In this review, we will evaluate the evidence and the potential role of 11 C-metomidate as a promising positron emission tomography (PET) tracer in clinical practice., Methods: A review of the English literature for articles describing the use of the tracer 11 C-metomidate in adrenal disorders., Results: A total of 12 studies were included in the systematic review, which altogether addressed the use of 11 C-metomidate in adrenal masses and the application of this tracer in primary aldosteronism., Conclusions: 11 C-metomidate, a selective inhibitor of 11-β-hydroxylase, demonstrated a high specificity for adrenocortical tissue. In addition, 11 C-metomidate is correlated with this enzyme activity making it a potentially useful PET tracer for the identification primary aldosteronism, in addition to detection of adrenocortical masses.

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.

Dengue virus (DENV) is a significant cause of morbidity in many regions of the world, with children at the greatest risk of developing severe dengue. NK cells, characterized by their ability to rapidly recognize and kill virally infected cells, are activated during acute DENV infection. However, their role in viral clearance versus pathogenesis has not been fully elucidated. Our goal was to profile the NK cell receptor-ligand repertoire to provide further insight into the function of NK cells during pediatric and adult DENV infection. We used mass cytometry to phenotype isolate NK cells and PBMCs from a cohort of DENV-infected children and adults. Using unsupervised clustering, we found that pediatric DENV infection leads to a decrease in total NK cell frequency with a reduction in the percentage of CD56 dim CD38 bright NK cells and an increase in the percentage of CD56 dim perforin bright NK cells. No such changes were observed in adults. Next, we identified markers predictive of DENV infection using a differential state test. In adults, NK cell expression of activation markers, including CD69, perforin, and Fas-L, and myeloid cell expression of activating NK cell ligands, namely Fas, were predictive of infection. In contrast, increased NK cell expression of the maturation marker CD57 and myeloid cell expression of inhibitory ligands, such as HLA class I molecules, were predictive of pediatric DENV infection. These findings suggest that acute pediatric DENV infection may result in diminished NK cell activation, which could contribute to enhanced pathogenesis and disease severity., (Copyright © 2020 The Authors.)

Despite the importance of Aedes, Haemagogus and Sabethes in the transmission of yellow fever virus (YFV) and the public health impacts of recent YFV epidemics in the Americas, relatively little has been reported on the biology and ecology of these vectors. Many Aedes, Haemagogus and Sabethes spp. in the American tropics inhabit and develop in the forest canopy and are difficult to sample with conventional entomological surveillance methods. We tested the utility of two previously developed phytotelmata-style oviposition traps (bamboo Guadua angustifolia) and (monkey-pot Lecythis minor), for collecting immature forms of these mosquitoes in a forest near the community of Aruza Abajo, Darién Province, Panama. Our results showed distribution of mosquito species emerging from the two types of traps was found to be significantly different (X 2  = 210.23; df = 14; P < 0.001), with significantly greater numbers of Sabethes (Peytonulus) aurescens (Lutz) and Sabethes (Peytonulus) undosus (Coquillett) emerging from the bamboo traps. More females of Sabethes (Sabethes) cyaneus (Fabricius) were captured in the monkey-pot traps, although the difference was not significant. No differences were observed in the average time to emergence for the two traps. These results suggest that various phytotelmata-style traps, including monkey-pot and bamboo, could be used to improve entomological surveillance of YFV vectors in the American tropic., Competing Interests: Declaration of Competing Interest The authors declare there are no competing interests., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Research on canopy arthropods has progressed from species inventories to the study of their interactions and networks, enhancing our understanding of how hyper-diverse communities are maintained. Previous studies often focused on sampling individual tree species, individual trees or their parts. We argue that such selective sampling is not ideal when analyzing interaction network structure, and may lead to erroneous conclusions. We developed practical and reproducible sampling guidelines for the plot-based analysis of arthropod interaction networks in forest canopies. Our sampling protocol focused on insect herbivores (leaf-chewing insect larvae, miners and gallers) and non-flying invertebrate predators (spiders and ants). We quantitatively sampled the focal arthropods from felled trees, or from trees accessed by canopy cranes or cherry pickers in 53 0.1 ha forest plots in five biogeographic regions, comprising 6,280 trees in total. All three methods required a similar sampling effort and provided good foliage accessibility. Furthermore, we compared interaction networks derived from plot-based data to interaction networks derived from simulated non-plot-based data focusing either on common tree species or a representative selection of tree families. All types of non-plot-based data showed highly biased network structure towards higher connectance, higher web asymmetry, and higher nestedness temperature when compared with plot-based data. Furthermore, some types of non-plot-based data showed biased diversity of the associated herbivore species and specificity of their interactions. Plot-based sampling thus appears to be the most rigorous approach for reconstructing realistic, quantitative plant-arthropod interaction networks that are comparable across sites and regions. Studies of plant interactions have greatly benefited from a plot-based approach and we argue that studies of arthropod interactions would benefit in the same way. We conclude that plot-based studies on canopy arthropods would yield important insights into the processes of interaction network assembly and dynamics, which could be maximised via a coordinated network of plot-based study sites., Competing Interests: The authors have declared that no competing interests exist.

Estimations of tropical insect diversity generally suffer from lack of known groups or faunas against which extrapolations can be made, and have seriously underestimated the diversity of some taxa. Here we report the intensive inventory of a four-hectare tropical cloud forest in Costa Rica for one year, which yielded 4332 species of Diptera, providing the first verifiable basis for diversity of a major group of insects at a single site in the tropics. In total 73 families were present, all of which were studied to the species level, providing potentially complete coverage of all families of the order likely to be present at the site. Even so, extrapolations based on our data indicate that with further sampling, the actual total for the site could be closer to 8000 species. Efforts to completely sample a site, although resource-intensive and time-consuming, are needed to better ground estimations of world biodiversity based on limited sampling., Competing Interests: The authors declare no competing interests.

Background: Current organ allocation policy and the rapid growth of mechanical support favor heart transplant (HT) candidates on left ventricular assist devices. HT candidates with hypertrophic cardiomyopathy (HCM) are usually not left ventricular assist device candidates and may have a disadvantage compared with dilated forms of cardiomyopathy., Methods and Results: Adult HT candidates registered in the Scientific Registry of Transplant Recipients database between 1999 and 2016 were included. HCM candidates were compared with ischemic cardiomyopathy (ICM) and non-ICM patients. Two eras were defined on the basis of the approval date of the first continuous-flow left ventricular assist device for bridge-to-transplant in the United States (2008). Patients outcomes were evaluated while on the waitlist and after HT. The proportion of patients with HCM listed for HT increased by 44% in era 2 compared with era 1. Waitlist mortality in patients with ICM (15.5%-8.7%) and non-ICM (14.2%-8.2%) declined across eras, but minimal decline was observed in HCM patients (11.7%-9.6%; P =0.06). In era 2, the 12-month rate of HT in HCM (64.8%) was comparable to that of ICM (60.9%) and non-ICM (62.7%) patients ( P =0.06). Post-transplant survival in HCM patients was the most favorable in the most recent era (1 year: 91.6% and 5 years: 82.5%; P <0.05 for all comparisons)., Conclusions: The number of patients with HCM in need of HT is increasing. Although post-transplant survival in HCM is excellent, waitlist mortality is substantial and with minimal decline in the most recent era, despite the frequent use of listing status upgrade by exception in this patient cohort. Different strategies to improve the performance of the organ allocation system in patients with HCM are needed., (© 2018 American Heart Association, Inc.)

Myiasis is a temporary infection of the skin or other organs with fly larvae. 1 The larvae develop into boil-like lesions. Creeping sensations and pain are usually described by patients. Following the maturation of the larvae, spontaneous exiting and healing is experienced. Herein we present a case of a traveler returning from Central African Republic. She does not recall insect bites. She never took off her clothing for recreational bathing, nor did she visit any rural areas. The lesions appeared on unexposed skin. The specific diagnosis was performed by morphologic characterization of the larvae, resulting in Cordylobia anthropophaga, the dominant form of myiasis in Africa. To our knowledge, this is the first reported case of C. anthropophaga in Latin America., (Copyright © 2018 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.)

Resource specialization is a key concept in ecology, but it is unexpectedly difficult to parameterize. Differences in resource availability, sampling effort and abundances preclude comparisons of incompletely sampled biotic interaction webs. Here, we extend the distance-based specialization index (DSI) that measures trophic specialization by taking resource phylogenetic relatedness and availability into account into a rescaled version, DSI*. It is a versatile metric of specialization that expands considerably the scope and applicability, hence the usefulness, of DSI. The new metric also accounts for differences in abundance and sampling effort of consumers, which enables robust comparisons among distinct guilds of consumers. It also provides an abundance threshold for the reliability of the metric for rare species, a very desirable property given the difficulty of assessing any aspect of rare species accurately. We apply DSI* to an extensive dataset on interactions between insect herbivores from four folivorous guilds and their host plants in Papua New Guinean rainforests. We demonstrate that DSI*, contrary to the original DSI, is largely independent of sample size and weakly and non-linearly related with several host specificity measures that do not adjust for plant phylogeny. Thus, DSI* provides further insights into host specificity patterns; moreover, it is robust to the number and phylogenetic diversity of plant species selected to be sampled for herbivores. DSI* can be used for a broad range of comparisons of distinct feeding guilds, geographical locations and ecological conditions. This is a key advance in elucidating the interaction structure and evolution of highly diversified systems.

The Intermediate Disturbance Hypothesis (IDH) is well-known in ecology providing an explanation for the role of disturbance in the coexistence of climax and colonist species. Here, we used the IDH as a framework to describe the role of forest disturbance in shaping the mosquito community structure, and to identify the ecological processes that increase the emergence of vector-borne disease. Mosquitoes were collected in central Panama at immature stages along linear transects in colonising, mixed and climax forest habitats, representing different levels of disturbance. Species were identified taxonomically and classified into functional categories (i.e., colonist, climax, disturbance-generalist, and rare). Using the Huisman-Olff-Fresco multi-model selection approach, IDH testing was done. We did not detect a unimodal relationship between species diversity and forest disturbance expected under the IDH; instead diversity peaked in old-growth forests. Habitat complexity and constraints are two mechanisms proposed to explain this alternative postulate. Moreover, colonist mosquito species were more likely to be involved in or capable of pathogen transmission than climax species. Vector species occurrence decreased notably in undisturbed forest settings. Old-growth forest conservation in tropical rainforests is therefore a highly-recommended solution for preventing new outbreaks of arboviral and parasitic diseases in anthropic environments.

Background: Reports about regulations and laws on Euthanasia and Physician Assisted Suicide (PAS) are becoming increasingly common in the media. Many groups have expressed opposition to euthanasia and PAS while those in favor argue that severely chronically ill and debilitated patients have a right to control the timing and manner of their death. Others argue that both PAS and euthanasia are ethically legitimate in rare and exceptional cases. Given that these discussions as well as the new and proposed laws and regulations may have a powerful impact on patients, caregivers, and health care providers, the International Association for Hospice and Palliative Care (IAHPC) has prepared this statement., Purpose: To describe the position of the IAHPC regarding Euthanasia and PAS., Method: The IAHPC formed a working group (WG) of seven board members and two staff officers who volunteered to participate in this process. An online search was performed using the terms "position statement", "euthanasia" "assisted suicide" "PAS" to identify existing position statements from health professional organizations. Only statements from national or pan-national associations were included. Statements from seven general medical and nursing associations and statements from seven palliative care organizations were identified. A working document including a summary of the different position statements was prepared and based on these, an initial draft was prepared. Online discussions among the members of the WG took place for a period of three months. The differences were reconciled by email discussions. The resulting draft was shared with the full board. Additional comments and suggestions were incorporated. This document represents the final version approved by the IAHPC Board of Directors., Result: IAHPC believes that no country or state should consider the legalization of euthanasia or PAS until it ensures universal access to palliative care services and to appropriate medications, including opioids for pain and dyspnea., Conclusion: In countries and states where euthanasia and/or PAS are legal, IAHPC agrees that palliative care units should not be responsible for overseeing or administering these practices. The law or policies should include provisions so that any health professional who objects must be allowed to deny participating., Competing Interests: Author Disclosure Statement No competing financial interests exist.

The Rhinellamargaritifera species group consists of 17 species of toads distributed in tropical and subtropical South America and eastern Central America. The identity of some of its species is poorly understood and there are numerous undescribed cryptic species. Among them, the status of Rhinellamargaritifera is one of the most problematic. Its range includes lowland rainforests separated by the Andes, the Chocoan rainforest to the west and the Amazonian rainforest to the east. This distribution is puzzling because the Andes are an old and formidable barrier to gene flow and therefore should generate vicariant speciation between disjunct lowland populations. Herein we clarify the taxonomy of populations of the Rhinellamargaritifera complex from Central America and the Chocó region of South America. The morphological and genetic variation of Rhinellamargaritifera was examined from 39 populations from Chocó, 24 from the upper Amazon region of Ecuador, and 37 from Panama, including the holotype of the Panamanian Rhinellaalata. Phylogenetic analyses were performed based on mitochondrial genes 12S rRNA, 16S rRNA, and cytochrome c oxidase I (COI) and the nuclear gene Tyrosinase (Tyr). The genetic and morphological data show that Panamanian and Chocoan populations are conspecific. In the phylogeny, populations from Chocó and Panama form a well-supported clade. The morphology of the holotype of Rhinellaalata falls within the variation range of Panamanian and Chocoan populations. Based on all this evidence, we assign the populations from western Ecuador and Panama to Rhinellaalata and demonstrate that the unusual distribution pattern of "Rhinellamargaritifera" on both sides of the Andes was an artifact of incorrectly defined species boundaries.

Objective: The aim of this review is to summarize the findings of studies that have evaluated non-surgical approaches for detoxification of implant body surfaces in vitro and in vivo, and to evaluate clinical trials on the use of these methodologies for treating peri-implant disease., Materials and Methods: A literature search was conducted using MEDLINE (Pubmed) from 1966 to 2013. In vitro and in vivo studies as well as clinical trials on non-surgical therapy were evaluated. The outcome variables were the ability of the therapeutic method to eliminate the biofilm and endotoxins from the implant surface, the changes in clinical parameters including probing depth, clinical attachment levels, bleeding on probing; radiographic bone fill and histological re-osseointegration., Results: From 134 articles found 35 were analyzed. The findings, advantages and disadvantages of using lasers as well as mechanical and chemical methods are discussed. Most of the in vivo and human studies used combination therapies which makes determining the efficacy of one specific method difficult. Most human studies are case series with short term longitudinal analysis without survival or failure reports., Conclusion: Complete elimination of the biofilms is difficult to achieve using these approaches. All therapies induce changes of the chemical and physical properties of the implant surface. Re-osseointegration may be difficult to achieve if not impossible without surgical access to ensure thorough debridement of the defect and detoxification of the implant surface. Combination protocols for non-surgical treatment of peri-implantitis in humans have shown some positive clinical results but long-term evaluation to evaluate the validity and reliability of the techniques is needed.

Many tropical fruits can be considered a reservoir of bioactive substances with a special interest due to their possible health-promoting properties. The interest in carotenoids from a nutritional standpoint has recently greatly increased, because of their important health benefits. Here we report the native carotenoids composition in six tropical fruits from Panama, which is considered a region of great biodiversity. The native carotenoid composition was directly investigated by an HPLC-DAD-APCI-MS methodology, for the first time. In Corozo 32 different carotenoids were detected, including a high content of β-carotene and lycopene. Sastra showed the highest content of zeaxanthin among the fruit investigated. In Sapote 22 different carotenoids were detected, including β-carotene and 10 different zeaxanthin-di-esters. Frutita showed a very high content of the apo-carotenoid β-citraurin, and of a number of its esters. In Maracuyà chino 14 carotenoids were detected, including a high amounts of mono-esterified lauric acid with β-cryptoxanthin and with cryptocapsin. Mamey rojo was characterised by ketocarotenoids with κ rings, both hydroxylated and not hydroxylated., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Bioassay-guided fractionation of the chloroform and ethanol extracts of Tovomita longifolia leaves using cytotoxic and antimicrobial assays resulted in the isolation of four new benzophenones, (E)-3-(2-hydroxy-7-methyl-3-methyleneoct-6-enyl)-2,4,6-trihydroxybenzophenone (1), (E)-3-(6-hydroxy-3,7-dimethylocta-2,7-dienyl)-2,4,6-trihydroxybenzophenone (2), 8-benzoyl-2-(4-methylpenten-3-yl)chromane-3,5,7-triol (3), and 5-benzoyl-1,1,4a-trimethyl-2,3,4,4a,9,9a-hexahydro-1H-xanthene-6,8-diol (4), and two known benzophenones, 4-geranyloxy-2,6-dihydroxybenzophenone (5) and 3-geranyl-2,4,6-trihydroxybenzophenone (6). The structures of 1-4 were established by spectroscopic means and by molecular modeling calculations. Compounds 1 and 3-5 demonstrated cytotoxic activities against breast (MCF-7), central nervous system (SF-268), and lung (H-460) human cancer cell lines, while compounds 3-6 showed antimicrobial activity against Klebsiella pneumoniae, Mycobacterium smegmatis, Pseudomonas aeruginosa, Salmonella gallinarum, and Staphylococcus aureus.

Attempts were made to overcome too-low reproductive output in the 48-h short-chronic microbiotest with the rotifer Brachionus calyciflorus fed with microalgae (Pseudokirchneriella subcapitata) from algal beads older than 4 months (Chemosphere 50 (2002a) 365). Prefeeding of freshly hatched rotifers prior to the start of the actual growth experiments resulted in a satisfactory reproduction (i.e., an intrinsic growth rate r > 0.65), even with subsequent feeding of the rotifers with microalgae from beads stored up to 1 year. Rotirich is an attractive alternative inert food compared with the mixture of microalgae and Spirulina, originally used to prefeed the rotifers. When the rotifers were prefed for 2 h with 30 microg/mL Rotirich, it was then not necessary to add Spirulina to the microalgal food from beads. The above findings are a substantial simplification of the testing procedure of the new short-chronic "culture/maintenance-free" Rotoxkit microbiotest.

To further validate the scope of use of the 6-day sediment contact microbiotest conducted with the ostracod Heterocypris incongruens, we compared the sensitivity of this small-scale culture/maintenance-free assay with the 14-day solid-phase Hyalella azteca test. The present study was undertaken within the framework of a Canadian bioremediation project on oil-contaminated freshwater sediments along an intertidal shoreline of the Saint-Lawrence River near the town of Sainte-Croix, Quebec, Canada. Sediment subsamples, collected during three sampling periods over 21 weeks from five plots (each with four replicates) contaminated with different treatments, were analyzed for their toxic effects on the two test species. Sediment samples taken immediately after the plots were spread with oil were very toxic to both crustaceans (mortality between 80% and 100%), but the mortality of the amphipods was substantially lower than that of the ostracods for samples collected after 6 weeks. Fifteen weeks after the onset of the controlled oil spill experiment, the sediments of all plots were still quite toxic to Heterocypris but not to Hyalella. Statistical analysis of the mortality figures was performed by Blaise et at. (2003) and revealed a statistically significant correlation (R = 0.584 at the P = 0.001 level) between data pairs. Analysis of the precision of the two assays showed a substantially higher uniformity (lower variation coefficients between the four replicas) of the ostracod results over that of the amphipod assay. This study corroborated the findings of two previous investigations conducted in Canada and in Belgium with the same test species. All three investigations concur in pointing out the potential of the new ostracod microbiotest as a reliable and sensitive ecotoxicological test for routine and low-cost monitoring of contaminated sediments., (Copyright 2003 Wiley Periodicals, Inc.)

A new "culture/maintenance-free" microbiotest has recently been developed for "direct-contact" toxicity determination of contaminated sediments. The 6-day Ostracodtoxkit F makes use of the neonates of the ostracod crustacean Heterocypris incongruens hatched from dormant eggs (cysts). The new low-cost assay has already been applied in three studies on river sediment from Flanders (Belgium) and from Canada and was found to perform comparably to the 10-day Hyalella azteca and Chironomus riparius tests in detecting and quantifying sediment toxicity. Taking into account that sediments are in fact underwater soils, the ostracod microbiotest was tentatively applied on 15 contaminated soils from Flanders (Belgium), and its sensitivity (based on mortality as the test criterion) was evaluated in comparison to the 28-day reproduction inhibition assay with the springtail Folsomia candida. The results revealed that the ostracod test species was as sensitive as or, in several samples, even more sensitive than the springtails. Leachate experiments on the same soil samples also showed that in most cases ostracod mortality was a result of the (nonsoluble) toxicants bound to the solid-phase particles, rather than of those that had dissolved in the water phase. Providing confirmation of these first findings through additional studies, the new culture/maintenance-free ostracod microbiotest seems to have good potential as a low-cost and user-friendly tool for routine toxicity monitoring of contaminated soils., (Copyright 2003 Wiley Periodicals, Inc.)

In view of the complexity and costs of "traditional" whole sediment assays, a "culture/maintenance free" direct contact microbiotest has been developed with the freshwater ostracod Heterocypris incongruens. The new Toxkit assay (named Ostracodtoxkit) has been applied to 33 sediment samples from Peninsula Harbour, located in Lake Superior of the Great Lakes water basin in Ontario, Canada. The microbiotest was applied in parallel to direct contact tests with the amphipod Hyalella azteca and the midge larva Chironomus riparius, to compare its relative sensitivity with that of the two "conventional" assays. The study was undertaken in the framework of remediation action plans for specific areas of concern, to enable decision making by the Canadian authorities for the restoration of impacted aquatic environments. Most sediments were found non-toxic (<20% mortality) to both the conventional test species and the ostracod. For the large majority of samples, a very good correspondence was found between the two crustacean test species for the intensity of the toxic signal "mortality", as reflected by a 0.71 (p<0.05) correlation coefficient. Growth inhibition, which is determined in the ostracod microbiotest as a sublethal effect criterion, allowed the earmarking of some sediment samples, which were apparently more toxic for the amphipod than to the ostracod. For 20% of the samples, substantially higher mortality scores were noted with the ostracod assay than with the midge larvae tests and the overall correlation coefficient between these two tests was lower (r=0.60,p<0.05). The results obtained in the present study corroborate those of previous research on sediments collected from various rivers in Flanders, Belgium, and confirm the potential of the new ostracod microbiotest as a reliable and sensitive low cost alternative for traditional whole sediment assays.

As important members of zooplankton communities worldwide, rotifers are used extensively in ecotoxicological research. Chronic rotifer tests are, however, dependent on live algal food which adds to the complexity, the variability and the costs of these bioassays. To bypass the former problem, experiments have been undertaken with the freshwater rotifer Brachionus calyciflorus, to determine their intrinsic growth rate (r) when fed for 48 h on a mixture of green algae (Raphidocelis subcapitata recently renamed Pseudokirchneriella subcapitata) obtained from algal beads stored for different periods of time, and other inert foods. All tests have been performed in disposable multiwells, in 1 ml cups each inoculated with 1 rotifer freshly hatched from dried cysts. The majority of the growth tests was performed in eight replicates. The investigations revealed that microalgae from algal beads stored for up to one year, in darkness, at 4 degrees C, supplemented with dried blue-green algae (Spirulina) gave satisfactory rotifer reproduction. The intrinsic growth rates of the rotifers, were, however, dependent on the storage time of the algal beads; the highests r's (0.7-0.8) were obtained with algae from beads not older than four months. Growth tests with combinations of P. subcapitata and other inert feeds revealed that the enrichment food Selco used in aquaculture, also gave the same reproductive output as the combination microalgae/Spirulina. A rotifer growth experiment with 18 replicates showed that the variation coefficient is below 20% when the tests comprise eight replicates. This study demonstrated that microalgae from beads, supplemented by other inert food, open the door for a practical and cost-effective short-chronic rotifer test, which is totally independent of the culturing of both the test species and its live food.

In view of the need for rapid and low-cost solid-phase assays for contaminated sediments, a new 6-day "culture/maintenance-free" microbiotest has been developed with the freshwater ostracod crustacean Heterocypris incongruens at the Laboratory for Biological Research in Aquatic Pollution at the Ghent University in Belgium. The sensitivity of the Ostracodtoxkit F has been compared with that of the 10-day sediment contact test with the amphipod crustacean Hyalella azteca and the two pore water assays (on the anostracan crustacean Thamnocephalus platyurus and the microalgae Raphidocelis subcapitata) selected by the Flemish Environmental Agency for initial hazard assessment of contaminated sediments. The exercise was performed on 26 sediments collected at random from various rivers of the Flemish hydrographic basin in Belgium. The toxicity data ranged from nontoxic to highly toxic for the solid-phase assays and showed that the mortality of the two test biota varied from "nearly identical" to "substantially different," depending on the sediment. The correlation coefficient for the data pairs was weakly positive (r = 0.60), mainly because of 5 samples for which a low mortality had been noted with the ostracod versus a much higher mortality for the amphipod. However, for 4 out of the 5 samples of concern, a substantial growth inhibition was recorded for H. incongruens, showing that this assay eventually performed as did the amphipod test in detecting the toxic character of the sediments. The comparison of toxicity data of the two solid-phase assays with those of the two pore water tests again confirmed that both types of bioassay provided complementary (nonredundant) information. On the basis of its various advantages (independence of stock culturing/maintenance, user-friendliness, precision, and time and cost savings) the new ostracod microbiotest appears to be a promising tool for routine toxicity assessment of contaminated sediments., (Copyright 2002 Wiley Periodicals, Inc.)

Experiments were carried out with neonates of the freshwater ostracod Heterocypris incongruens to verify and complete previous choices of test parameters for a new culture/maintenance-free solid-phase microbiotest for freshwater sediments. From trials with increasing volumes of reference sediment, it was concluded that 300 microL was the most appropriate amount of substrate to be put in 12-cup multiwell plates with 2 mL of standard freshwater. Tests in 3-9 replicates eventually showed that six parallels were needed to have good assay precision (repeatability). Application of the final test protocol to oil-contaminated sediments from the St. Lawrence River in Canada revealed that the 6-day chronic ostracod microbiotest had less variation in repeated tests than did the 10-day contact assay with Hyalella azteca and hence can be considered more precise. Based on the 95% confidence intervals for mortality and growth of the ostracods in the controls (reference sediment) of the 56 tests carried out for the Canadian project, a validity threshold of 20% for mortality was eventually selected, in analogy with the acceptability limits applied in many chronic bioassays. A minimum length of 600 microm in the control sediment after 6 days' exposure was also taken as the threshold for good health of the test organisms and for reliable test conditions. The new microbiotest has been tailored in a handy and user-friendly new toxkit, the Ostracodtoxkit, which is particularly suited for cost-effective routine monitoring., (Copyright 2002 Wiley Periodicals, Inc.)

Experiments were carried out with neonates of the freshwater ostracod Heterocypris incongruens hatched from cysts in order to develop a new culture/maintenance-free solid-phase microbiotest for the toxicity assessment of contaminated sediments. Based on preliminary investigations, a number of test parameters were investigated for a short-chronic assay: hatching time, size of the cups of the multiwell test plates, feeding of the test organisms prior to the test, amount of supplemental algal food, volume of sediment, and duration of the test. On the basis of the findings, a test protocol was formulated for a 6-day assay in 12-cup multiwell plates with 10 organisms per cup and 3 replicates. The test organisms were collected 52 h after the start of the incubation of the cysts in standard freshwater at 25 degrees C under continuous illumination after a 4-h prefeeding with 1.3 mg/mL Spirulina. The test biota in the cups were exposed to 300 microL of test sediment in 2 mL of standard freshwater with 3 x 10(7) live algal cells (Raphidocelis subcapitata) as food supplement. Calibrated sand was used as a reference sediment. Mortality and growth of the ostracods were determined after 6 days' incubation at 25 degrees C in darkness. The selected test parameters for the new microbiotest were found adequate for toxicity determination of natural sediments compared with the 10-day contact test with the amphipod Hyalella azteca., (Copyright 2002 Wiley Periodicals, Inc.)