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1.
PLoS Pathog ; 19(10): e1011435, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37906600

RESUMEN

The Aspergillus fumigatus unfolded protein response (UPR) is a two-component relay consisting of the ER-bound IreA protein, which splices and activates the mRNA of the transcription factor HacA. Spliced hacA accumulates under conditions of acute ER stress in vitro, and UPR null mutants are hypovirulent in a murine model of invasive pulmonary infection. In this report, we demonstrate that a hacA deletion mutant (ΔhacA) is furthermore avirulent in a model of fungal keratitis, a corneal infection, and an important cause of ocular morbidity and unilateral blindness worldwide. Interestingly, we demonstrate that A. fumigatus hacA is spliced in infected lung samples, but not in the cornea, suggesting the amount of ER stress experienced by the fungus varies upon the host niche. To better understand how the UPR contributes to fungal cell biology across a spectrum of ER-stress levels, we employed transcriptomics on the wild-type and ΔhacA strains in glucose minimal media (low stress), glucose minimal media with dithiothreitol (high stress), and gelatin minimal media as a proxy for the nutrient stress encountered in the cornea (mid-level stress). These data altogether reveal a unique HacA-dependent transcriptome under each condition, suggesting that HacA activity is finely-tuned and required for proper fungal adaptation in each environment. Taken together, our results indicate that the fungal UPR could serve as an important antifungal target in the setting of both invasive pulmonary and corneal infections.


Asunto(s)
Aspergillus fumigatus , Queratitis , Animales , Ratones , Respuesta de Proteína Desplegada , Queratitis/genética , Nutrientes , Glucosa/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
2.
Clin Infect Dis ; 78(Supplement_2): S175-S182, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38662705

RESUMEN

BACKGROUND: Neglected tropical diseases are responsible for considerable morbidity and mortality in low-income populations. International efforts have reduced their global burden, but transmission is persistent and case-finding-based interventions rarely target asymptomatic individuals. METHODS: We develop a generic mathematical modeling framework for analyzing the dynamics of visceral leishmaniasis in the Indian sub-continent (VL), gambiense sleeping sickness (gHAT), and Chagas disease and use it to assess the possible contribution of asymptomatics who later develop disease (pre-symptomatics) and those who do not (non-symptomatics) to the maintenance of infection. Plausible interventions, including active screening, vector control, and reduced time to detection, are simulated for the three diseases. RESULTS: We found that the high asymptomatic contribution to transmission for Chagas and gHAT and the apparently high basic reproductive number of VL may undermine long-term control. However, the ability to treat some asymptomatics for Chagas and gHAT should make them more controllable, albeit over relatively long time periods due to the slow dynamics of these diseases. For VL, the toxicity of available therapeutics means the asymptomatic population cannot currently be treated, but combining treatment of symptomatics and vector control could yield a quick reduction in transmission. CONCLUSIONS: Despite the uncertainty in natural history, it appears there is already a relatively good toolbox of interventions to eliminate gHAT, and it is likely that Chagas will need improvements to diagnostics and their use to better target pre-symptomatics. The situation for VL is less clear, and model predictions could be improved by additional empirical data. However, interventions may have to improve to successfully eliminate this disease.


Asunto(s)
Infecciones Asintomáticas , Enfermedad de Chagas , Leishmaniasis Visceral , Modelos Teóricos , Enfermedades Desatendidas , Humanos , Enfermedades Desatendidas/prevención & control , Enfermedades Desatendidas/epidemiología , Enfermedad de Chagas/transmisión , Enfermedad de Chagas/prevención & control , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/tratamiento farmacológico , Infecciones Asintomáticas/epidemiología , Leishmaniasis Visceral/prevención & control , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/transmisión , Leishmaniasis Visceral/tratamiento farmacológico , Tripanosomiasis Africana/prevención & control , Tripanosomiasis Africana/epidemiología , Tripanosomiasis Africana/transmisión , Tripanosomiasis Africana/tratamiento farmacológico , India/epidemiología , Animales
3.
Malar J ; 23(1): 38, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38308253

RESUMEN

BACKGROUND: It was hypothesized that glucose-6-phosphate dehydrogenase (G6PD) deficiency confers a protective effect against malaria infection, however, safety concerns have been raised regarding haemolytic toxicity caused by radical cure with 8-aminoquinolines in G6PD-deficient individuals. Malaria elimination and control are also complicated by the high prevalence of G6PD deficiency in malaria-endemic areas. Hence, accurate identification of G6PD deficiency is required to identify those who are eligible for malaria treatment using 8-aminoquinolines. METHODS: The prevalence of G6PD deficiency among 408 Thai participants diagnosed with malaria by microscopy (71), and malaria-negative controls (337), was assessed using a phenotypic test based on water-soluble tetrazolium salts. High-resolution melting (HRM) curve analysis was developed from a previous study to enable the detection of 15 common missense, synonymous and intronic G6PD mutations in Asian populations. The identified mutations were subjected to biochemical and structural characterisation to understand the molecular mechanisms underlying enzyme deficiency. RESULTS: Based on phenotypic testing, the prevalence of G6PD deficiency (< 30% activity) was 6.13% (25/408) and intermediate deficiency (30-70% activity) was found in 15.20% (62/408) of participants. Several G6PD genotypes with newly discovered double missense variants were identified by HRM assays, including G6PD Gaohe + Viangchan, G6PD Valladolid + Viangchan and G6PD Canton + Viangchan. A significantly high frequency of synonymous (c.1311C>T) and intronic (c.1365-13T>C and c.486-34delT) mutations was detected with intermediate to normal enzyme activity. The double missense mutations were less catalytically active than their corresponding single missense mutations, resulting in severe enzyme deficiency. While the mutations had a minor effect on binding affinity, structural instability was a key contributor to the enzyme deficiency observed in G6PD-deficient individuals. CONCLUSIONS: With varying degrees of enzyme deficiency, G6PD genotyping can be used as a complement to phenotypic screening to identify those who are eligible for 8-aminoquinolines. The information gained from this study could be useful for management and treatment of malaria, as well as for the prevention of unanticipated reactions to certain medications and foods in the studied population.


Asunto(s)
Deficiencia de Glucosafosfato Deshidrogenasa , Malaria , Humanos , Deficiencia de Glucosafosfato Deshidrogenasa/epidemiología , Deficiencia de Glucosafosfato Deshidrogenasa/genética , Deficiencia de Glucosafosfato Deshidrogenasa/diagnóstico , Tailandia/epidemiología , Glucosafosfato Deshidrogenasa/genética , Glucosafosfato Deshidrogenasa/análisis , Malaria/epidemiología , Aminoquinolinas/efectos adversos
4.
Malar J ; 22(1): 60, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36803858

RESUMEN

BACKGROUND: Rapid diagnostic tests (RDTs) are effective tools to diagnose and inform the treatment of malaria in adults and children. The recent development of a highly sensitive rapid diagnostic test (HS-RDT) for Plasmodium falciparum has prompted questions over whether it could improve the diagnosis of malaria in pregnancy and pregnancy outcomes in malaria endemic areas. METHODS: This landscape review collates studies addressing the clinical performance of the HS-RDT. Thirteen studies were identified comparing the HS-RDT and conventional RDT (co-RDT) to molecular methods to detect malaria in pregnancy. Using data from five completed studies, the association of epidemiological and pregnancy-related factors on the sensitivity of HS-RDT, and comparisons with co-RDT were investigated. The studies were conducted in 4 countries over a range of transmission intensities in largely asymptomatic women. RESULTS: Sensitivity of both RDTs varied widely (HS-RDT range 19.6 to 85.7%, co-RDT range 22.8 to 82.8% compared to molecular testing) yet HS-RDT detected individuals with similar parasite densities across all the studies including different geographies and transmission areas [geometric mean parasitaemia around 100 parasites per µL (p/µL)]. HS-RDTs were capable of detecting low-density parasitaemias and in one study detected around 30% of infections with parasite densities of 0-2 p/µL compared to the co-RDT in the same study which detected around 15%. CONCLUSION: The HS-RDT has a slightly higher analytical sensitivity to detect malaria infections in pregnancy than co-RDT but this mostly translates to only fractional and not statistically significant improvement in clinical performance by gravidity, trimester, geography or transmission intensity. The analysis presented here highlights the need for larger and more studies to evaluate incremental improvements in RDTs. The HS-RDT could be used in any situation where co-RDT are currently used for P. falciparum diagnosis, if storage conditions can be adhered to.


Asunto(s)
Malaria Falciparum , Malaria , Adulto , Embarazo , Niño , Humanos , Femenino , Plasmodium falciparum , Prueba de Diagnóstico Rápido , Sensibilidad y Especificidad , Malaria Falciparum/diagnóstico , Malaria Falciparum/epidemiología , Pruebas Diagnósticas de Rutina/métodos , Antígenos de Protozoos/análisis
5.
BMC Infect Dis ; 23(1): 110, 2023 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-36823583

RESUMEN

BACKGROUND: Rapid determination of an individual's antibody status can be beneficial in understanding an individual's immune response to SARS-CoV-2 and for initiation of therapies that are only deemed effective in sero-negative individuals. Antibody lateral flow tests (LFTs) have potential to address this need as a rapid, point of care test. METHODS: Here we present a proof-of-concept evaluation of eight LFT brands using sera from 95 vaccinated individuals to determine sensitivity for detecting vaccination generated antibodies. Samples were analysed on eight different brands of antibody LFT and an automated chemiluminescent microparticle immunoassay (CMIA) that identifies anti-spike antibodies which was used as our reference standard. RESULTS: All 95 (100%) participants tested positive for anti-spike antibodies by the chemiluminescent microparticle immunoassay (CMIA) reference standard post-dose two of their SARS-CoV-2 vaccine: BNT162b2 (Pfizer/BioNTech, n = 60), AZD1222 (AstraZeneca, n = 31), mRNA-1273 (Moderna, n = 2) and Undeclared Vaccine Brand (n = 2). Sensitivity increased from dose one to dose two in six out of eight LFTs with three tests achieving 100% sensitivity at dose two in detecting anti-spike antibodies. CONCLUSIONS: These tests are demonstrated to be highly sensitive to detect raised antibody levels in vaccinated individuals. RDTs are low cost and rapid alternatives to ELISA based systems.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , Vacuna BNT162 , ChAdOx1 nCoV-19 , COVID-19/diagnóstico , COVID-19/prevención & control , SARS-CoV-2 , Anticuerpos Antivirales , Vacunación
6.
J Neurosci ; 41(4): 648-662, 2021 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-33262247

RESUMEN

Stress may promote emotional and cognitive disturbances, which differ by sex. Adverse outcomes, including memory disturbances, are typically observed following chronic stress, but are now being recognized also after short events, including mass shootings, assault, or natural disasters, events that consist of concurrent multiple acute stresses (MAS). Prior work has established profound and enduring effects of MAS on memory in males. Here we examined the effects of MAS on female mice and probed the role of hormonal fluctuations during the estrous cycle on MAS-induced memory problems and the underlying brain network and cellular mechanisms. Female mice were impacted by MAS in an estrous cycle-dependent manner: MAS impaired hippocampus-dependent spatial memory in early-proestrous mice, characterized by high levels of estradiol, whereas memory of mice stressed during estrus (low estradiol) was spared. As spatial memory requires an intact dorsal hippocampal CA1, we examined synaptic integrity in mice stressed at different cycle phases and found a congruence of dendritic spine density and spatial memory deficits, with reduced spine density only in mice stressed during high estradiol cycle phases. Assessing MAS-induced activation of brain networks interconnected with hippocampus, we identified differential estrous cycle-dependent activation of memory- and stress-related regions, including the amygdala. Network analyses of the cross-correlation of fos expression among these regions uncovered functional connectivity that differentiated impaired mice from those not impaired by MAS. In conclusion, the estrous cycle modulates the impact of MAS on spatial memory, and fluctuating physiological levels of sex hormones may contribute to this effect.SIGNIFICANCE STATEMENT: Effects of stress on brain functions, including memory, are profound and sex-dependent. Acute stressors occurring simultaneously result in spatial memory impairments in males, but effects on females are unknown. Here we identified estrous cycle-dependent effects of such stresses on memory in females. Surprisingly, females with higher physiological estradiol experienced stress-induced memory impairment and a loss of underlying synapses. Memory- and stress-responsive brain regions interconnected with hippocampus were differentially activated across high and low estradiol mice, and predicted memory impairment. Thus, at functional, network, and cellular levels, physiological estradiol influences the effects of stress on memory in females, providing insight into mechanisms of prominent sex differences in stress-related memory disorders, such as post-traumatic stress disorder.


Asunto(s)
Estrógenos , Trastornos de la Memoria/fisiopatología , Trastornos de la Memoria/psicología , Estrés Psicológico/fisiopatología , Estrés Psicológico/psicología , Animales , Encéfalo/fisiopatología , Región CA1 Hipocampal/fisiopatología , Espinas Dendríticas , Ciclo Estral , Estro , Femenino , Masculino , Aprendizaje por Laberinto , Ratones , Ratones Endogámicos C57BL , Red Nerviosa/fisiopatología , Proteínas Proto-Oncogénicas c-fos/genética , Memoria Espacial , Útero/inervación , Útero/fisiopatología
7.
J Appl Microbiol ; 133(5): 3191-3200, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35946113

RESUMEN

AIMS: The environment is increasingly recognized as an important reservoir of antimicrobial resistance genes (ARGs), which can be identified using molecular platforms. Yet, environmental surveillance remains an underutilised tool as there is no agreement on the best strategy for sample processing. We aim to develop a low-cost extraction method independent to commercial kits or reagents. METHODS AND RESULTS: We present a novel, magnetic bead-based method for the isolation of ARGs from river water named MagnaExtract. We present this with analytic limit of detection as well as a case study in Southern Malawi. Here we compare the DNA yield from MagnaExtract with commercially available QIAGEN kits and the crude boil and spin method, using a high-resolution melt analysis PCR panel designed for the detection of third-generation cephalosporin and carbapenem-resistant genes from 98 water samples. CONCLUSION: The MagnaExtract method is comparable, and in some instance's superior to commercially available kits for the isolation of ARGs from river water samples. SIGNIFICANCE AND IMPACT OF THE STUDY: The MagnaExtract approach offers a simple, affordable, high yielding extraction method that could be used for the detection of ARGs from river water samples in surveillance campaigns in East Africa.


Asunto(s)
Antibacterianos , Ríos , Antibacterianos/farmacología , Antibacterianos/análisis , Genes Bacterianos/genética , Farmacorresistencia Bacteriana/genética , Malaui , Carbapenémicos , Cefalosporinas , Fenómenos Magnéticos , Agua/análisis
8.
Arch Sex Behav ; 51(4): 2183-2198, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35471679

RESUMEN

This mixed-methods study investigated the relation among gender identity (i.e., self-perceived gender similarity to girls and boys; self-perceived parental and peer pressure to conform to gender norms) and stereotyping about weight (i.e., anti-fat stereotypes), weight change, and appearance in 83 girls ages 6-9 (Mage = 7.60 years, SD = .85; 65% White, 16% Mixed/Other, 11% Black, 8% Latina) in the U.S. Stereotypes about weight change were assessed with open-ended responses (i.e., qualitatively), and the rest of the constructs were assessed with closed-ended responses (i.e., quantitatively). There was a positive association between pressure from parents to conform to gender norms and appearance stereotypes, and between pressure from peers and negative stereotypes about the fat and thin figures. Girls who were more gender typical, or more similar to girls, were more likely to endorse appearance stereotypes. There was no significant relation among stereotypes about weight change and gender identity. Many girls deemed the fat figure as unattractive, physically restrained, unhealthy, and likely to be bullied and believed that the fat figure should change back to look like a thinner figure. Most girls were aware that exercising, eating healthy, and dietary restriction can lead to weight loss and that food consumption and lack of exercise can lead to weight gain. Findings suggest that certain aspects of weight (anti-fat) and appearance stereotypes are closely linked to gender identity in girls, whereas other aspects of weight stereotypes (e.g., stereotypes about weight change) are so pervasive that they are common in most girls, regardless of their gender identity.


Asunto(s)
Identidad de Género , Estereotipo , Niño , Femenino , Hispánicos o Latinos , Humanos , Masculino , Padres , Grupo Paritario
9.
Clin Infect Dis ; 72(Suppl 3): S180-S187, 2021 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-33906229

RESUMEN

BACKGROUND: Control of visceral leishmaniasis (VL) on the Indian subcontinent has been highly successful. Control efforts such as indoor residual spraying and active case detection will be scaled down or even halted over the coming years. We explored how after scale-down, potential recurrence of VL cases may be predicted based on population-based surveys of antibody or antigenemia prevalence. METHODS: Using a stochastic age-structured transmission model of VL, we predicted trends in case incidence and biomarker prevalence over time after scaling down control efforts when the target of 3 successive years without VL cases has been achieved. Next, we correlated biomarker prevalence with the occurrence of new VL cases within 10 years of scale-down. RESULTS: Occurrence of at least 1 new VL case in a population of 10 000 was highly correlated with the seroprevalence and antigenemia prevalence at the moment of scale-down, or 1 or 2 years afterward. Receiver operating characteristic curves indicated that biomarker prevalence in adults provided the most predictive information, and seroprevalence was a more informative predictor of new VL cases than antigenemia prevalence. Thresholds for biomarker prevalence to predict occurrence of new VL cases with high certainty were robust to variation in precontrol endemicity. CONCLUSIONS: The risk of recrudescence of VL after scaling down control efforts can be monitored and mitigated by means of population-based surveys. Our findings highlight that rapid point-of-care diagnostic tools to assess (preferably) seroprevalence or (otherwise) antigenemia in the general population could be a key ingredient of sustainable VL control.


Asunto(s)
Leishmaniasis Visceral , Adulto , Preescolar , Humanos , Incidencia , Estudios Longitudinales , Prevalencia , Estudios Seroepidemiológicos
10.
Clin Infect Dis ; 72(8): 1463-1466, 2021 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-32984870

RESUMEN

Due to the COVID-19 pandemic, many key neglected tropical disease (NTD) activities have been postponed. This hindrance comes at a time when the NTDs are progressing towards their ambitious goals for 2030. Mathematical modelling on several NTDs, namely gambiense sleeping sickness, lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminthiases (STH), trachoma, and visceral leishmaniasis, shows that the impact of this disruption will vary across the diseases. Programs face a risk of resurgence, which will be fastest in high-transmission areas. Furthermore, of the mass drug administration diseases, schistosomiasis, STH, and trachoma are likely to encounter faster resurgence. The case-finding diseases (gambiense sleeping sickness and visceral leishmaniasis) are likely to have fewer cases being detected but may face an increasing underlying rate of new infections. However, once programs are able to resume, there are ways to mitigate the impact and accelerate progress towards the 2030 goals.


Asunto(s)
COVID-19 , Medicina Tropical , Humanos , Enfermedades Desatendidas/epidemiología , Pandemias , SARS-CoV-2
11.
Emerg Infect Dis ; 27(9): 2445-2449, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34424174

RESUMEN

We developed a testing program for severe acute respiratory syndrome coronavirus 2 in an urban Latinx neighborhood in Providence, Rhode Island, USA. Approximately 11% of Latinx participants (n = 180) tested positive. Culturally tailored, community-based programs that reduce barriers to testing help identify persons at highest risk for coronavirus disease.


Asunto(s)
COVID-19 , SARS-CoV-2 , Prueba de COVID-19 , Humanos , Área sin Atención Médica , Rhode Island/epidemiología
12.
Emerg Infect Dis ; 27(3): 719-727, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33622482

RESUMEN

GeneXpert-based testing with Xpert MTB/RIF or Ultra assays is essential for tuberculosis diagnosis. However, testing may be affected by cartridge and staff shortages. More efficient testing strategies could help, especially during the coronavirus disease pandemic. We searched the literature to systematically review whether GeneXpert-based testing of pooled sputum samples achieves sensitivity and specificity similar to testing individual samples; this method could potentially save time and preserve the limited supply of cartridges. From 6 publications, we found 2-sample pools using Xpert MTB/RIF had 87.5% and 96.0% sensitivity (average sensitivity 94%; 95% CI 89.0%-98.0%) (2 studies). Four-sample pools averaged 91% sensitivity with Xpert MTB/RIF (2 studies) and 98% with Ultra (2 studies); combining >4 samples resulted in lower sensitivity. Two studies reported that pooling achieved 99%-100% specificity and 27%-31% in cartridge savings. Our results show that pooling may improve efficiency of GeneXpert-based testing.


Asunto(s)
COVID-19/epidemiología , Técnicas de Diagnóstico Molecular , Mycobacterium tuberculosis/aislamiento & purificación , Esputo/microbiología , Tuberculosis/diagnóstico , Análisis Costo-Beneficio , Humanos , Mycobacterium tuberculosis/genética , SARS-CoV-2 , Sensibilidad y Especificidad , Manejo de Especímenes
13.
Emerg Infect Dis ; 27(1)2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33256890

RESUMEN

We investigated the dynamics of seroconversion in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. During March 29-May 22, 2020, we collected serum samples and associated clinical data from 177 persons in London, UK, who had SARS-CoV-2 infection. We measured IgG against SARS-CoV-2 and compared antibody levels with patient outcomes, demographic information, and laboratory characteristics. We found that 2.0%-8.5% of persons did not seroconvert 3-6 weeks after infection. Persons who seroconverted were older, were more likely to have concurrent conditions, and had higher levels of inflammatory markers. Non-White persons had higher antibody concentrations than those who identified as White; these concentrations did not decline during follow-up. Serologic assay results correlated with disease outcome, race, and other risk factors for severe SARS-CoV-2 infection. Serologic assays can be used in surveillance to clarify the duration and protective nature of humoral responses to SARS-CoV-2 infection.


Asunto(s)
COVID-19/sangre , COVID-19/inmunología , Inmunoglobulina G/sangre , SARS-CoV-2 , Seroconversión , Adulto , Anciano , Anticuerpos Antivirales/sangre , COVID-19/fisiopatología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
14.
J Antimicrob Chemother ; 76(12): 3286-3295, 2021 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-34450619

RESUMEN

OBJECTIVES: AGILE is a Phase Ib/IIa platform for rapidly evaluating COVID-19 treatments. In this trial (NCT04746183) we evaluated the safety and optimal dose of molnupiravir in participants with early symptomatic infection. METHODS: We undertook a dose-escalating, open-label, randomized-controlled (standard-of-care) Bayesian adaptive Phase I trial at the Royal Liverpool and Broadgreen Clinical Research Facility. Participants (adult outpatients with PCR-confirmed SARS-CoV-2 infection within 5 days of symptom onset) were randomized 2:1 in groups of 6 participants to 300, 600 and 800 mg doses of molnupiravir orally, twice daily for 5 days or control. A dose was judged unsafe if the probability of 30% or greater dose-limiting toxicity (the primary outcome) over controls was 25% or greater. Secondary outcomes included safety, clinical progression, pharmacokinetics and virological responses. RESULTS: Of 103 participants screened, 18 participants were enrolled between 17 July and 30 October 2020. Molnupiravir was well tolerated at 300, 600 and 800 mg doses with no serious or severe adverse events. Overall, 4 of 4 (100%), 4 of 4 (100%) and 1 of 4 (25%) of the participants receiving 300, 600 and 800 mg molnupiravir, respectively, and 5 of 6 (83%) controls, had at least one adverse event, all of which were mild (≤grade 2). The probability of ≥30% excess toxicity over controls at 800 mg was estimated at 0.9%. CONCLUSIONS: Molnupiravir was safe and well tolerated; a dose of 800 mg twice daily for 5 days was recommended for Phase II evaluation.


Asunto(s)
COVID-19 , SARS-CoV-2 , Adulto , Teorema de Bayes , Humanos , Proyectos de Investigación , Resultado del Tratamiento
15.
Mod Pathol ; 34(5): 961-982, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33024305

RESUMEN

Immunohistochemical analysis of p57 expression and molecular genotyping accurately subclassify molar specimens into complete hydatidiform mole (CHM) and partial hydatidiform mole (PHM) and distinguish these from nonmolar specimens. Characteristics of a prospective series of potentially molar specimens analyzed in a large gynecologic pathology practice are summarized. Of 2217 cases (2160 uterine, 57 ectopic), 2080 (94%) were successfully classified: 571 CHMs (570 uterine, 1 ectopic), 498 PHMs (497 uterine, 1 ectopic), 900 nonmolar (including 147 trisomies, 19 digynic triploids, and 4 donor egg conceptions), and 56 androgenetic/biparental mosaics; 137 were complex or unsatisfactory and not definitively classified. CHMs dominated in patients aged < 21 and >45 years and were the only kind of molar conception found in the latter group. Of 564 successfully immunostained CHMs, 563 (99.8%) were p57-negative (1 p57-positive [retained maternal chromosome 11] androgenetic by genotyping). Of 153 genotyped CHMs, 148 (96.7%) were androgenetic (85% monospermic) and 5 were biparental, the latter likely familial biparental hydatidiform moles. Of 486 successfully immunostained PHMs, 481 (99%) were p57-positive (3 p57-negative [loss of maternal chromosome 11], 2 unknown mechanism). Of 497 genotyped PHMs, 484 (97%) were diandric triploid (99% dispermic) and 13 were triandric tetraploid (all at least dispermic). Of 56 androgenetic/biparental mosaics, 37 had a p57-negative complete molar component (16 confirmed as androgenetic by genotyping). p57 expression is highly correlated with genotyping, serving as a reliable marker for CHMs, and identifies molar components and androgenetic cell lines in mosaic conceptions. Correlation of morphology, p57 expression, genotyping data, and history are required to recognize familial biparental hydatidiform moles and donor egg conceptions, as the former can be misclassified as nonmolar and the latter can be misclassified as dispermic CHM on the basis of isolated genotyping results.


Asunto(s)
Inhibidor p57 de las Quinasas Dependientes de la Ciclina/metabolismo , Mola Hidatiforme/diagnóstico , Neoplasias Uterinas/diagnóstico , Adolescente , Adulto , Niño , Femenino , Humanos , Mola Hidatiforme/genética , Mola Hidatiforme/metabolismo , Mola Hidatiforme/patología , Inmunohistoquímica , Persona de Mediana Edad , Embarazo , Estudios Prospectivos , Neoplasias Uterinas/genética , Neoplasias Uterinas/metabolismo , Neoplasias Uterinas/patología , Adulto Joven
16.
Malar J ; 20(1): 194, 2021 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-33879156

RESUMEN

BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) deficiency, the most common enzymopathy in humans, is prevalent in tropical and subtropical areas where malaria is endemic. Anti-malarial drugs, such as primaquine and tafenoquine, can cause haemolysis in G6PD-deficient individuals. Hence, G6PD testing is recommended before radical treatment against vivax malaria. Phenotypic assays have been widely used for screening G6PD deficiency, but in heterozygous females, the random lyonization causes difficulty in interpreting the results. Over 200 G6PD variants have been identified, which form genotypes associated with differences in the degree of G6PD deficiency and vulnerability to haemolysis. This study aimed to assess the frequency of G6PD mutations using a newly developed molecular genotyping test. METHODS: A multiplexed high-resolution melting (HRM) assay was developed to detect eight G6PD mutations, in which four mutations can be tested simultaneously. Validation of the method was performed using 70 G6PD-deficient samples. The test was then applied to screen 725 blood samples from people living along the Thai-Myanmar border. The enzyme activity of these samples was also determined using water-soluble tetrazolium salts (WST-8) assay. Then, the correlation between genotype and enzyme activity was analysed. RESULTS: The sensitivity of the multiplexed HRM assay for detecting G6PD mutations was 100 % [95 % confidence interval (CI): 94.87-100 %] with specificity of 100 % (95 % CI: 87.66-100 %). The overall prevalence of G6PD deficiency in the studied population as revealed by phenotypic WST-8 assay was 20.55 % (149/725). In contrast, by the multiplexed HRM assay, 27.17 % (197/725) of subjects were shown to have G6PD mutations. The mutations detected in this study included four single variants, G6PD Mahidol (187/197), G6PD Canton (4/197), G6PD Viangchan (3/197) and G6PD Chinese-5 (1/197), and two double mutations, G6PD Mahidol + Canton (1/197) and G6PD Chinese-4 + Viangchan (1/197). A broad range of G6PD enzyme activities were observed in individuals carrying G6PD Mahidol, especially in females. CONCLUSIONS: The multiplexed HRM-based assay is sensitive and reliable for detecting G6PD mutations. This genotyping assay can facilitate the detection of heterozygotes, which could be useful as a supplementary approach for high-throughput screening of G6PD deficiency in malaria endemic areas before the administration of primaquine and tafenoquine.


Asunto(s)
Técnicas de Genotipaje/métodos , Deficiencia de Glucosafosfato Deshidrogenasa/epidemiología , Malaria Vivax/epidemiología , Femenino , Deficiencia de Glucosafosfato Deshidrogenasa/genética , Humanos , Malaria Vivax/parasitología , Masculino , Tailandia/epidemiología
17.
BMC Infect Dis ; 21(1): 784, 2021 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-34372788

RESUMEN

BACKGROUND: SARS-CoV-2 is frequently shed in the stool of patients hospitalised with COVID-19. The extent of faecal shedding of SARS-CoV-2 among individuals in the community, and its potential to contribute to spread of disease, is unknown. METHODS: In this prospective, observational cohort study among households in Liverpool, UK, participants underwent weekly nasal/throat swabbing to detect SARS-CoV-2 virus, over a 12-week period from enrolment starting July 2020. Participants that tested positive for SARS-CoV-2 were asked to provide a stool sample three and 14 days later. In addition, in October and November 2020, during a period of high community transmission, stool sampling was undertaken to determine the prevalence of SARS-CoV-2 faecal shedding among all study participants. SARS-CoV-2 RNA was detected using Real-Time PCR. RESULTS: A total of 434 participants from 176 households were enrolled. Eighteen participants (4.2%: 95% confidence interval [CI] 2.5-6.5%) tested positive for SARS-CoV-2 virus on nasal/throat swabs and of these, 3/17 (18%: 95% CI 4-43%) had SARS-CoV-2 detected in stool. Two of three participants demonstrated ongoing faecal shedding of SARS-CoV-2, without gastrointestinal symptoms, after testing negative for SARS-CoV-2 in respiratory samples. Among 165/434 participants without SARS-CoV-2 infection and who took part in the prevalence study, none had SARS-CoV-2 in stool. There was no demonstrable household transmission of SARS-CoV-2 among households containing a participant with faecal shedding. CONCLUSIONS: Faecal shedding of SARS-CoV-2 occurred among community participants with confirmed SARS-CoV-2 infection. However, during a period of high community transmission, faecal shedding of SARS-CoV-2 was not detected among participants without SARS-CoV-2 infection. It is unlikely that the faecal-oral route plays a significant role in household and community transmission of SARS-CoV-2.


Asunto(s)
COVID-19 , SARS-CoV-2 , Estudios de Cohortes , Humanos , Estudios Prospectivos , ARN Viral , Reino Unido/epidemiología , Esparcimiento de Virus
18.
Nature ; 528(7580): S102-8, 2015 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-26633763

RESUMEN

Countries in the Indian subcontinent have committed to reducing the incidence of kala-azar, a clinical manifestation of visceral leishmaniasis, to below 1 in 10,000 by 2020. We address the role of timing of use and accuracy of diagnostics in kala-azar control and elimination. We use empirical data on health-seeking behaviour and health-system performance from the Indian state of Bihar, Bangladesh and Nepal to parameterize a mathematical model. Diagnosis of cases is key to case management, control and surveillance. Treatment of cases prevents onward transmission, and we show that the differences in time to diagnosis in these three settings explain the observed differences in incidence. Shortening the time from health-care seeking to diagnosis is likely to lead to dramatic reductions in incidence in Bihar, bringing the incidence down to the levels seen in Bangladesh and Nepal. The results emphasize the importance of maintaining population and health-system awareness, particularly as transmission and disease incidence decline. We explore the possibility of diagnosing patients before the onset of clinical kala-azar (before 14 days fever), and show that this could have a marked impact on incidence, even for a moderately sensitive test. However, limited specificity (that results in false positives) is a major barrier to such a strategy. Diagnostic tests of high specificity used at an early stage of active infection, even if sensitivity is only moderate, could have a key role in the control of kala-azar, and prevent its resurgence when paired with the passive health-care system and tests of high sensitivity, such as the test for rK39 antibody response.


Asunto(s)
Pruebas Diagnósticas de Rutina , Conductas Relacionadas con la Salud , Leishmaniasis Visceral/diagnóstico , Leishmaniasis Visceral/transmisión , Bangladesh/epidemiología , Humanos , Incidencia , India/epidemiología , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/inmunología , Nepal/epidemiología , Sensibilidad y Especificidad
19.
J Infect Dis ; 221(Suppl 5): S546-S553, 2020 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-31841593

RESUMEN

BACKGROUND: Control of visceral leishmaniasis (VL) on the Indian subcontinent relies on prompt detection and treatment of symptomatic cases. Detection efforts influence the observed VL incidence and how well it reflects the underlying true incidence. As control targets are defined in terms of observed cases, there is an urgent need to understand how changes in detection delay and population coverage of improved detection affect VL control. METHODS: Using a mathematical model for transmission and control of VL, we predict the impact of reduced detection delays and/or increased population coverage of the detection programs on observed and true VL incidence and mortality. RESULTS: Improved case detection, either by higher coverage or reduced detection delay, causes an initial rise in observed VL incidence before a reduction. Relaxation of improved detection may lead to an apparent temporary (1 year) reduction in VL incidence, but comes with a high risk of resurging infection levels. Duration of symptoms in detected cases shows an unequivocal association with detection effort. CONCLUSIONS: VL incidence on its own is not a reliable indicator of the performance of case detection programs. Duration of symptoms in detected cases can be used as an additional marker of the performance of case detection programs.


Asunto(s)
Leishmaniasis Visceral/diagnóstico , Leishmaniasis Visceral/prevención & control , Erradicación de la Enfermedad , Humanos , Incidencia , India/epidemiología , Leishmaniasis Visceral/epidemiología , Modelos Biológicos
20.
J Vis Commun Med ; 44(3): 97-116, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33988480

RESUMEN

The Pernkopf Atlas has posed an ethical dilemma for the past 30 years. Although its illustrations are of an indisputably high quality, its unethical origins yield questions with its use. This study aimed to identify successful methods for creating equal if not higher quality anatomical visualisations through an analysis and comparison of past and present medical illustrator's techniques. Pernkopf's illustrations were not used as an anatomical reference to ensure the new visuals were ethical; instead other existing visuals and written sources were compiled and reviewed to create an original 3D model of the posterior cervical triangle using ZBrush 2020. Some visualisation techniques used by Pernkopf were used as a part of this project (i.e. rendering in partial colour) this technique is not unique to Pernkopf and was also used by Henry Carter, the illustrator of Grey's anatomy. The survey was distributed to 78 participants with a strong anatomical or medical/biological art background. The reception to the new resource was positive; participants favoured it in terms of quality and ease of understanding. However, participants noted that the images in the survey were not the same resolution which may have skewed the results in favour of the new image. When rated for detail compared to the Pernkopf Atlas, the number of structures in the resource need to be increased before it can be ranked equally to the Pernkopf Atlas for detail. Participants did note that they may have selected differently depending on what was inferred by quality and detail in the survey.


Asunto(s)
Anatomía Artística , Ilustración Médica , Humanos , Encuestas y Cuestionarios
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