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Coralsnakes of the genus Micrurus are a diverse group of venomous snakes ranging from the southern United States to southern South America. Much uncertainty remains over the genus diversity, and understanding Micrurus systematics is of medical importance. In particular, the widespread Micrurus nigrocinctus spans from Mexico throughout Central America and into Colombia, with a number of described subspecies. This study provides new insights into the phylogenetic relationships within M. nigrocinctus by examining sequence data from a broad sampling of specimens from Mexico, Guatemala, Honduras, Nicaragua, Costa Rica, and Panama. The recovered phylogenetic relationships suggest that M. nigrocinctus is a species complex originating in the Pliocene and composed of at least three distinct species-level lineages. In addition, recovery of highly divergent clades supports the elevation of some currently recognized subspecies to the full species rank while others may require synonymization.

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Hemosporidians are a monophyletic group of protozoan parasites infecting all terrestrial vertebrate orders. Although Plasmodium is the most studied genus within the Haemosporidia, this research effort is heavily biased toward mammal and bird hosts. We screened 205 specimens of at least 18 reptile species from Brazil using a partial mitochondrial cytochrome b gene marker. Positive samples were sequenced and included in a phylogenetic assessment. Four positive PCR products matched others identified as Plasmodium using BLAST from 3 different host species, Ameiva ameiva, Tropidurus hispidus, and Hemidactylus mabouia. Recovery of similar haplotypes in the native T. hispidus and exotic H. mabouia (99.9%) indicate potential host-switching.

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BACKGROUND: HIV-exposed-uninfected (HEU) infants have increased infectious morbidity and mortality; little is known about their levels of inflammation and monocyte activation. METHODS: Plasma samples obtained at birth and 6 months from 86 HEU mother-infant pairs enrolled in the National Institute of Child Health and Human Development cohorts in Brazil were compared with 88 HIV-unexposed mother-infant pairs. HIV-infected mothers received antiretroviral therapy during pregnancy, their infants received zidovudine prophylaxis and were not breastfed. IL-6, soluble TNFα receptor I (sTNF-RI) and II, soluble CD14, soluble CD163, IFN-γ-induced protein 10 (IP-10), vascular cell adhesion molecule, oxidized LDL, D-dimer and high-sensitivity C-reactive protein were assayed by ELISA at birth and at 6 months. sTNF-RI and IL-6 were considered coprimary endpoints. RESULTS: Among HIV-infected mothers, 79% had HIV-RNA less than 400 copies/ml prior to delivery. Compared with HIV-unexposed, HEU infants had a lower mean gestational age (38.7 vs. 39.3 weeks) and weight (3.1 vs. 3.3 kg); and reached lower weight (5.9 vs. 8.5 kg) and height (53.6 vs. 68.8 cm) at 6 months. With the exception of vascular cell adhesion molecule, inflammatory markers were generally higher (P ≤ 0.005) in HEU at birth, but at 6 months only sTNF-RI and IL-6 remained higher. For HEU pairs, only IP-10 was associated with maternal levels at birth (P < 0.001). In HEU, elevated levels of high-sensitivity C-reactive protein and IP-10 at birth were associated with lower weight at birth (P = 0.04) and at 6 months (P = 0.04). CONCLUSION: HIV-exposed infants have heightened inflammation and monocyte activation at birth, which for some markers persisted to 6 months of life and was not related to maternal inflammatory status. Inflammation may contribute to the increased HEU infectious morbidity and poor growth.

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Despite the advances of molecular tools, new nematode species are still described mainly based on morphological characters. Parapharyngodon and Thelandros are two genera of oxyurids with unclear related taxonomic histories. Here we use morphological characters (linear measurements and categorical variables) and genetic information (18S rRNA, 28S rRNA and COI partial gene sequences) to confirm the relationships between representatives of these two genera and to determine whether they can be discriminated morphologically. Genetic results confirm the existence of two main clades, mostly congruent with Parapharyngodon and Thelandros genera but with several discordances. Thelandros is polyphyletic, with two of the species analysed (T. filiformis and T. tinerfensis) being part of the Thelandros clade, but with a third one (T. galloti) falling within the Parapharyngodon clade. Regarding the Parapharyngodon clade, P. cubensis, P. scleratus and Parapharyngodon sp. from Mexico form congruent lineages, while most P. echinatus samples cluster in another group, with one exception. Interestingly, P. micipsae samples are scattered across the Parapharyngodon clade, suggesting that they were misidentified or rather represent alternative morphotypes of other species. Morphological analysis identified the length of the tail, number of caudal papillae, position of the nerve ring, presence of caudal alae and length of the lateral alae as reliable characters to distinguish between Parapharyngodon and Thelandros genetic clades. Our study highlights the current taxonomic inconsistency in these groups, mainly derived from the exclusive use of morphological data. As such, we advocate for the routine implementation of molecular data in nematode taxonomic studies.

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Over the last decades, modern lifestyle and environment have contributed to a shift in gut microbial colonization patterns and composition. Not only intestinal but also extraintestinal disorders have been proposed to be linked to changes in the gut microbiome. There is increasing evidence from clinical, epidemiologic and animal studies exploring associations between the dysbiotic microbiome and an increased risk of allergic, inflammatory, autoimmune, and metabolic diseases. The fetus is essentially sterile until the amniotic sac ruptures. After that, the maternal microbiota of the mouth, intestine, vagina and urinary tract contribute to the initial seeding of neonatal microbiota. Newborns are mainly inoculated at birth in the passage through the birth canal (vertical transmission). A number of exposure events occur afterwards (horizontal transmission), and by age 2, an infant's microbiota composition becomes indistinguishable from that of an adult. In mammalian evolution, the potential loss or change in vertical transmission of microbiota from mother to offspring could be compensated through horizontally transmitted microbiota (fecally contaminated drinking and bathing water, frequent physical contact, social crowding, and large families). However, the progressive loss of vertically transmitted microbiota without horizontal replacement represents a cumulative birth cohort phenomenon. Events that decrease microbiota diversity have been classically associated with risk of disease

En las últimas décadas, el estilo de vida y el ambiente moderno, han contribuido a un cambio en los patrones y la composición de colonización microbiana intestinal. No sólo se ha propuesto que los trastornos intestinales, sino también los extraintestinales, estarían relacionados con cambios en la microbioma intestinal. Cada vez hay más evidencias de estudios clínicos, epidemiológicos y en animales que exploran las asociaciones entre el microbioma disbiótico y un mayor riesgo de enfermedades alérgicas, inflamatorias, autoinmunes y metabólicas. El feto es esencialmente estéril hasta que el saco amniótico se rompe. Después de eso, la microbiota materna de la boca, el intestino, la vagina y el tracto urinario contribuye a la siembra inicial de la microbiota neonatal. Los recién nacidos se inoculan principalmente al nacer en el pasaje a través del canal de parto (transmisión vertical). Después de una serie de eventos de exposición (transmisión horizontal), a los 2 años, la composición de microbiota de un bebé se vuelve indistinguible de la de un adulto. En la evolución de los mamíferos, la pérdida o cambio potencial en la transmisión vertical de la microbiota de la madre a la descendencia podría compensarse mediante la microbiota transmitida horizontalmente (agua potable y de baño contaminada con heces, contacto físico frecuente, aglomeración social y familias numerosas). Sin embargo, la pérdida progresiva de microbiota transmitida verticalmente sin reemplazo horizontal representa un fenómeno de cohorte de nacimiento acumulativo. Los eventos que disminuyen la diversidad de la microbiota se han asociado clásicamente con el riesgo de enfermedad.

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We estimated the prevalence of human immunodeficiency virus (HIV) disclosure in children from a prospective observational cohort study conducted at clinical sites in Brazil, Mexico, and Peru. Fewer than half of the children in this study knew their HIV status, which highlights the need for better strategies for disclosure that are age and culturally appropriate.

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Based on both unique morphological characteristics of the gamont, distinct changes caused to the host erythrocyte and analysis of partial 18S rRNA gene sequences, a new parasite of the genus Hepatozoon Miller, 1908 is described from the snake Philodryas nattereri Steindachner (Squamata: Dipsadidae) in northeastern Brazil. The new species, Hepatozoon musa n. sp., is characterized by large and curved mature gamonts (18.9 ± 0.9 µm in length and 3.8 ± 0.3 µm in width) that considerably engorge infected host erythrocytes and displace the nucleus laterally, which become longer and thinner. Phylogenetic estimates indicate the new species is more closely related to the recently described Hepatozoon cuestensis O'Dwyer, Moço, Paduan, Spenassatto, Silva & Ribolla, 2013, from Brazilian rattlesnakes. These recent findings highlight the need for further studies of Hepatozoon to better determine the biodiversity of this common but poorly-studied parasite group.

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Antiretroviral adherence in the postpartum period is crucial for maternal health and decreasing the risk of mother-to-child HIV transmission and transmission to sexual partners. Self-reported antiretroviral adherence was examined between 6- to 12-weeks and 30 months postpartum among 270 HIV-infected women enrolled in a prospective cohort study from 2008 to 2010 at multiple sites in Latin America. Adherence data were collected at each study visit to quantify the proportion of prescribed antiretrovirals taken during the previous three days, assess the timing of the last missed dose, and identify predictors of adherence. Mean adherence rates were 89.5% at 6-12 weeks and 92.4% at 30 months; the proportions with perfect adherence were 80.3% and 83.6%, respectively. The overall trend for perfect adherence was not significant (p = 0.71). In adjusted regression modelling, younger age was associated with an increased probability of non-perfect adherence at 18 and 24 months postpartum. Other factors associated with increased probability of non-perfect adherence were higher parity, current use of alcohol and tobacco, and more advanced HIV disease. Women with perfect adherence had lower viral loads. Interventions for alcohol and tobacco use cessation, and support for young women and those with advanced HIV disease should be considered to improve postpartum adherence.

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Objective: To evaluate the occurrence, clinical presentations and diagnostic methods for tuberculosis in a cohort of HIV-infected infants, children and adolescents from Latin America. Methods: A retrospective analysis of children with tuberculosis and HIV was performed within a prospective observational cohort study conducted at multiple clinical sites in Latin America. Results: Of 1114 HIV-infected infants, children, and adolescents followed from 2002 to 2011, 69 that could be classified as having confirmed or presumed tuberculosis were included in this case series; 52.2% (95% CI: 39.8-64.4%) had laboratory-confirmed tuberculosis, 15.9% (95% CI: 8.2-26.7%) had clinically confirmed disease and 31.9% (95% CI: 21.2-44.2%) had presumed tuberculosis. Sixty-six were perinatally HIV-infected. Thirty-two (61.5%) children had a history of contact with an adult tuberculosis case; however information on exposure to active tuberculosis was missing for 17 participants. At the time of tuberculosis diagnosis, 39 were receiving antiretroviral therapy. Sixteen of these cases may have represented immune reconstitution inflammatory syndrome. Conclusions: Our study emphasizes the need for adequate contact tracing of adult tuberculosis cases and screening for HIV or tuberculosis in Latin American children diagnosed with either condition. Preventive strategies in tuberculosis-exposed, HIV-infected children should be optimized. .

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OBJECTIVE: To evaluate the occurrence, clinical presentations and diagnostic methods for tuberculosis in a cohort of HIV-infected infants, children and adolescents from Latin America. METHODS: A retrospective analysis of children with tuberculosis and HIV was performed within a prospective observational cohort study conducted at multiple clinical sites in Latin America. RESULTS: Of 1114 HIV-infected infants, children, and adolescents followed from 2002 to 2011, 69 that could be classified as having confirmed or presumed tuberculosis were included in this case series; 52.2% (95% CI: 39.8-64.4%) had laboratory-confirmed tuberculosis, 15.9% (95% CI: 8.2-26.7%) had clinically confirmed disease and 31.9% (95% CI: 21.2-44.2%) had presumed tuberculosis. Sixty-six were perinatally HIV-infected. Thirty-two (61.5%) children had a history of contact with an adult tuberculosis case; however information on exposure to active tuberculosis was missing for 17 participants. At the time of tuberculosis diagnosis, 39 were receiving antiretroviral therapy. Sixteen of these cases may have represented immune reconstitution inflammatory syndrome. CONCLUSIONS: Our study emphasizes the need for adequate contact tracing of adult tuberculosis cases and screening for HIV or tuberculosis in Latin American children diagnosed with either condition. Preventive strategies in tuberculosis-exposed, HIV-infected children should be optimized.

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Renal toxicity is a concern in HIV-infected children receiving antiretrovirals. However, the prevalence [1.7%; 95% confidence interval (CI): 1.0-2.6%] and incidence of kidney dysfunction (0.17 cases/100 person-years; 95% CI: 0.04-0.30) were rare in this multicenter cohort study of 1,032 perinatally HIV-infected Latin American and Caribbean children followed from 2002 to 2011.

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We report a study of ν(µ) charged-current quasielastic events in the segmented scintillator inner tracker of the MINERvA experiment running in the NuMI neutrino beam at Fermilab. The events were selected by requiring a µ- and low calorimetric recoil energy separated from the interaction vertex. We measure the flux-averaged differential cross section, dσ/dQ², and study the low energy particle content of the final state. Deviations are found between the measured dσ/dQ² and the expectations of a model of independent nucleons in a relativistic Fermi gas. We also observe an excess of energy near the vertex consistent with multiple protons in the final state.

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BACKGROUND: Perinatally HIV-infected (PHIV) children may be at risk of undervaccination. Vaccination coverage rates among PHIV and HIV-exposed uninfected (HEU) children in Latin America and the Caribbean were compared. METHODS: All PHIV and HEU children born from 2002 to 2007 who were enrolled in a multisite observational study conducted in Latin America and the Caribbean were included in this analysis. Children were classified as up to date if they had received the recommended number of doses of each vaccine at the appropriate intervals by 12 and 24 months of age. Fisher's exact test was used to analyze the data. Covariates potentially associated with a child's HIV status were considered in multivariable logistic regression modeling. RESULTS: Of 1156 eligible children, 768 (66.4%) were HEU and 388 (33.6%) were PHIV. HEU children were significantly (P < 0.01) more likely to be up to date by 12 and 24 months of age for all vaccines examined. Statistically significant differences persisted when the analyses were limited to children enrolled before 12 months of age. Controlling for birth weight, sex, primary caregiver education and any use of tobacco, alcohol or illegal drugs during pregnancy did not contribute significantly to the logistic regression models. CONCLUSIONS: PHIV children were significantly less likely than HEU children to be up to date for their childhood vaccinations at 12 and 24 months of age, even when limited to children enrolled before 12 months of age. Strategies to increase vaccination rates in PHIV are needed.

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