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1.
PLOS Glob Public Health ; 3(1): e0000546, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36962749

RESUMO

This study aims to detail the capacity strengthening process of the Ghana Ob/Gyn postgraduate training program in order to inform a model by which international academic medicine partnerships can form, grow, and effectively tackle development challenges. A qualitative analysis with grounded theory methodological approach was utilized. Convenience and purposive sampling were used to select certified Ob/Gyn training program graduates. Interviews were conducted face-to-face in in Accra, Kumasi, Cape Coast, and Tamale, Ghana between June 21 to August 20, 2017. An additional data analysis of 48 semi-structured interviews previously collected for another study were examined for factors pertinent to graduate career development. Coded data were grouped according to themes and subthemes. Emerging themes demonstrated that graduates further complete the maternal care team and facilitate collaboration amongst healthcare workers. Themes also included graduates' pursuit of subspecialty training and research. Graduates cited the training program as key to their professional development. Graduates assume leadership roles in hospital management and operations, teaching, mentoring, interprofessional maternal care team, and knowledge-sharing. Graduates expressed eagerness to subspecialize and to advance their research training and skills. The results suggest a growth model of international academic medicine partnerships from basic obstetric training to advanced training. The model is developed for adaptability in other SSA countries and low-resource settings so that it may effectively strengthen health workforce capacity. We hope that this program can serve as a model for other partnerships in medical specialties.

2.
Int J Impot Res ; 35(3): 234-241, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36274189

RESUMO

The removal of non-pathogenic foreskin from the penis of healthy neonates and infants for non-religious reasons is routinely practiced in many parts of the world. High level data from well-designed randomized controlled trials of circumcision in neonates and infants does not guide clinical practice. Reliable counts of immediate and short term circumcision complications are difficult to estimate. Emerging evidence suggests routine neonatal circumcision could lead to long term psychological, physical, and sexual complications in some men. The stigma associated with discussing circumcision complications creates a prevalence paradox where the presence of significant circumcision complications is higher than reported. Prior to the Internet, there were very few forums for men from diverse communities, who were troubled about their circumcision status, to discuss and compare stories. To investigate the long term consequences of circumcision, we reviewed 135 posts from 109 individual users participating in a circumcision grief subsection of Reddit, an internet discussion board. We identified three major categories of complications: physical such as pain during erections and lost sensitivity, psychological such as anxiety and violation of autonomy, and sexual such as feeling that the sexual experience was negatively altered or being unable to complete a sexual experience. We also identified a "discovery process" where some men described coming into awareness of their circumcision status. These findings suggest that neonatal circumcision can have significant adverse consequences for adult men. The removal of normal foreskin tissue should be limited to adult men who choose the procedure for cosmetic reasons or when medically indicated.


Assuntos
Circuncisão Masculina , Pênis , Masculino , Adulto , Recém-Nascido , Humanos , Autorrelato , Pênis/cirurgia , Circuncisão Masculina/efeitos adversos , Circuncisão Masculina/métodos , Comportamento Sexual , Prepúcio do Pênis/cirurgia
3.
Front Immunol ; 13: 912038, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36330531

RESUMO

Lymphoid tissues are an important HIV reservoir site that persists in the face of antiretroviral therapy and natural immunity. Targeting these reservoirs by harnessing the antiviral activity of local tissue-resident memory (TRM) CD8+ T-cells is of great interest, but limited data exist on TRM-like cells within lymph nodes of people living with HIV (PLWH). Here, we studied tonsil CD8+ T-cells obtained from PLWH and uninfected controls from South Africa. We show that these cells are preferentially located outside the germinal centers (GCs), the main reservoir site for HIV, and display a low cytolytic and a transcriptionally TRM-like profile distinct from blood CD8+ T-cells. In PLWH, CD8+ TRM-like cells are expanded and adopt a more cytolytic, activated, and exhausted phenotype not reversed by antiretroviral therapy (ART). This phenotype was enhanced in HIV-specific CD8+ T-cells from tonsils compared to matched blood suggesting a higher antigen burden in tonsils. Single-cell transcriptional and clonotype resolution showed that these HIV-specific CD8+ T-cells in the tonsils express heterogeneous signatures of T-cell activation, clonal expansion, and exhaustion ex-vivo. Interestingly, this signature was absent in a natural HIV controller, who expressed lower PD-1 and CXCR5 levels and reduced transcriptional evidence of T-cell activation, exhaustion, and cytolytic activity. These data provide important insights into lymphoid tissue-derived HIV-specific CD8+ TRM-like phenotypes in settings of HIV remission and highlight their potential for immunotherapy and targeting of the HIV reservoirs.


Assuntos
Linfócitos T CD8-Positivos , Infecções por HIV , Humanos , Memória Imunológica , Tonsila Palatina , Receptores CXCR5 , Infecções por HIV/tratamento farmacológico
4.
HPB (Oxford) ; 24(11): 1989-1993, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35985970

RESUMO

BACKGROUND: This prospective study compared scoring systems in predicting adverse outcomes in HIV associated acute pancreatitis (HIV+ve AP) METHODS: Systemic inflammatory response syndrome (SIRS), Glasgow criteria, C-reactive protein (CRP), bedside index of severity in acute pancreatitis (BISAP) and APACHE II scores using standard cut-off values were used to predict the endpoint of moderate and severe disease in HIV-ve and HIV+ve patients and in CD4 counts above and below 200 cells/mm3. RESULTS: Ninety (38%) of 238 patients with AP were HIV+ve. Fifteen had organ failure, 33 local complications and 12 patients died. Advanced age was not associated with severe disease. The APACHE II was the best predictor of severe disease in HIV+ve (AUC 0.88) and HIV-ve patients (AUC 0.81) and CRP was the poorest predictor (AUC 0.59) in HIV+ve patients. In HIV+ve patients with CD4 counts greater and less than 200 cells/mm3 the Glasgow and APACHE II scores were the best prognosticators (AUC > 0.8) and BISAP in patients with CD4 > 200 cells/mm3 (AUC 0.90). CONCLUSION: The APACHE II score was most effective irrespective of HIV status whereas the BISAP scores was better in CD4 > 200 cells/mm3.


Assuntos
Infecções por HIV , Pancreatite , Humanos , Pancreatite/complicações , Pancreatite/diagnóstico , Doença Aguda , Estudos Prospectivos , Infecções por HIV/complicações , Infecções por HIV/diagnóstico , Valor Preditivo dos Testes , Índice de Gravidade de Doença , Estudos Retrospectivos , Prognóstico , Proteína C-Reativa/análise
6.
JCI Insight ; 6(22)2021 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-34618690

RESUMO

HIV infection in the human gastrointestinal (GI) tract is thought to be central to HIV progression, but knowledge of this interaction is primarily limited to cohorts within Westernized countries. Here, we present a large cohort recruited from high HIV endemic areas in South Africa and found that people living with HIV (PLWH) presented at a younger age for investigation in the GI clinic. We identified severe CD4+ T cell depletion in the GI tract, which was greater in the small intestine than in the large intestine and not correlated with years on antiretroviral treatment (ART) or plasma viremia. HIV-p24 staining showed persistent viral expression, particularly in the colon, despite full suppression of plasma viremia. Quantification of mucosal antiretroviral (ARV) drugs revealed no differences in drug penetration between the duodenum and colon. Plasma markers of gut barrier breakdown and immune activation were elevated irrespective of HIV, but peripheral T cell activation was inversely correlated with loss of gut CD4+ T cells in PLWH alone. T cell activation is a strong predictor of HIV progression and independent of plasma viral load, implying that the irreversible loss of GI CD4+ T cells is a key event in the HIV pathogenesis of PLWH in South Africa, yet the underlying mechanisms remain unknown.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Infecções por HIV/imunologia , Ativação Linfocitária/imunologia , Doença Crônica , Humanos
7.
Biol J Linn Soc Lond ; 133(3): 817-834, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34220190

RESUMO

The Northern Rocky Mountain ecosystem supports rich biological diversity with many endemic and rare species. Extant endemics display two biogeographic patterns: widespread species with fragmented populations, and narrow-range endemics. These distributions are shown by the congeneric snails Anguispira kochi occidentalis and Anguispira nimapuna. These two taxa are disjunct from the remaining species of the genus, which achieves its greatest diversity in eastern North America. Given the disjunct nature of A. k. occidentalis and A. nimapuna, we here present a mtDNA phylogeny of the genus that includes both eastern and western species to assess the phylogenetic position of A. k. occidentalis and A. nimapuna. We then reconstruct the demographic history of A. k. occidentalis and A. nimapuna by analysing current patterns of genetic variation and interpreting the results considering the historical biogeography of the region. Both A. k. occidentalis and A. nimapuna represent unique taxa that are genetically and geographically distinct from their congeners. The current distribution and genetic structure of A. k. occidentalis has been shaped by both historical isolation in refugia and more recent northward shifts, whereas A. nimapuna is represented by two populations with shallow divergence in an area of long-term habitat stability.

8.
JCI Insight ; 6(16)2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-34252054

RESUMO

SARS-CoV-2 infects epithelial cells of the human gastrointestinal (GI) tract and causes related symptoms. HIV infection impairs gut homeostasis and is associated with an increased risk of COVID-19 fatality. To investigate the potential link between these observations, we analyzed single-cell transcriptional profiles and SARS-CoV-2 entry receptor expression across lymphoid and mucosal human tissue from chronically HIV-infected individuals and uninfected controls. Absorptive gut enterocytes displayed the highest coexpression of SARS-CoV-2 receptors ACE2, TMPRSS2, and TMPRSS4, of which ACE2 expression was associated with canonical interferon response and antiviral genes. Chronic treated HIV infection was associated with a clear antiviral response in gut enterocytes and, unexpectedly, with a substantial reduction of ACE2 and TMPRSS2 target cells. Gut tissue from SARS-CoV-2-infected individuals, however, showed abundant SARS-CoV-2 nucleocapsid protein in both the large and small intestine, including an HIV-coinfected individual. Thus, upregulation of antiviral response genes and downregulation of ACE2 and TMPRSS2 in the GI tract of HIV-infected individuals does not prevent SARS-CoV-2 infection in this compartment. The impact of these HIV-associated intestinal mucosal changes on SARS-CoV-2 infection dynamics, disease severity, and vaccine responses remains unclear and requires further investigation.


Assuntos
Enzima de Conversão de Angiotensina 2/análise , Infecções por HIV/virologia , Mucosa Intestinal/virologia , SARS-CoV-2/isolamento & purificação , Serina Endopeptidases/análise , Adulto , Doença Crônica , Feminino , Humanos , Mucosa Intestinal/química , Masculino , Pessoa de Meia-Idade
9.
Mol Phylogenet Evol ; 156: 107038, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33285289

RESUMO

Phylogenetic relationships among the squids and cuttlefishes (Cephalopoda:Decapodiformes) have resisted clarification for decades, despite multiple analyses of morphological, molecular and combined data sets. More recently, analyses of complete mitochondrial genomes and hundreds of nuclear loci have yielded similarly ambiguous results. In this study, we re-evaluate hypotheses of decapodiform relationships by increasing taxonomic breadth and utilizing higher-quality genome and transcriptome data for several taxa. We also employ analytical approaches to (1) identify contamination in transcriptome data, (2) better assess model adequacy, and (3) account for potential biases. Using this larger data set, we consistently recover a clade comprising Myopsida (closed-eye squid), Sepiida (cuttlefishes), and Oegopsida (open-eye squid) that is sister to a Sepiolida (bobtail and bottletail squid) clade. Idiosepiida (pygmy squid) is consistently recovered as the sister group to all sampled decapodiform lineages. Further, a weighted Shimodaira-Hasegawa test applied to one of our larger data matrices rejects all alternatives to these ordinal-level relationships. At present, available nuclear genome-scale data support nested clades of relatively large-bodied decapodiform cephalopods to the exclusion of pygmy squids, but improved taxon sampling and additional genomic data will be needed to test these novel hypotheses rigorously.


Assuntos
Decapodiformes/classificação , Decapodiformes/genética , Filogenia , Animais , Genoma Mitocondrial , Funções Verossimilhança , Transcriptoma/genética
10.
Front Immunol ; 11: 579743, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117384

RESUMO

The intestinal mucosa is enriched for unconventional T-cells, including mucosal associated invariant T-cells (MAIT), invariant natural killer T-cells (iNKT) and γδ T-cells. These cells are activated by bacterial metabolites, lipid antigens and cytokines, and are important for intestinal barrier integrity. The loss of gut homeostasis observed in HIV infection is central to disease pathogenesis, and studies have highlighted impairment of particular unconventional T-cell subsets within a specific gut compartment. However, although the small and large intestine are distinct niches, the overall impact of HIV on unconventional T-cells across the gut mucosal has not been well-studied. We hypothesized that compartment specific differences in the unconventional T-cell repertoire would exist between the small and large intestine, due to increasing bacterial loads and microbial diversity; and that the impact of HIV infection might differ depending on the compartment examined. We used mass cytometry, flow cytometry and unbiased T-cell receptor profiling to quantify unconventional T-cells in blood and tissue from the small (duodenum) and large (colon) intestine in HIV infected and uninfected participants undergoing examination for a range of intestinal conditions. Overall, we find distinct compartmentalisation of T-cells between blood, duodenum and colon, with iNKT cells significantly enriched in the duodenum and δ-1 expressing γδ T-cells in the colon. In addition, we observe greater clonal expansion of conventional TCRs in the duodenum, suggestive of stronger adaptive immunity in this compartment. Conversely, we find evidence of an expanded unconventional TCR repertoire in the colon, which contained far more overlapping "donor unrestricted" sequences than the duodenum. Twelve of these TCRs were highly "MAIT-like" and 3 were unique to the colon, suggesting an enrichment of donor unrestricted T-cells (DURTs) in this compartment. Unexpectedly, however, no significant impact of HIV infection on any of the unconventional T-cell subsets measured was observed in either mucosal site in terms of frequency or TCR repertoire. Further studies are required to investigate the importance of these unconventional T-cell subsets to intestinal homeostasis within the different gut compartments and determine if they are functionally impaired during HIV infection.


Assuntos
Infecções por HIV/imunologia , HIV-1/fisiologia , Mucosa Intestinal/imunologia , Células T Invariantes Associadas à Mucosa/imunologia , Células T Matadoras Naturais/imunologia , Linfócitos T/imunologia , Adulto , Células Cultivadas , Feminino , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Adulto Jovem
11.
Obstet Gynecol ; 136(4): 657-662, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32925626

RESUMO

The maternal mortality ratio in the United States is increasing; understanding the significance of this change and developing effective responses requires a granular analysis of the contributing factors that a well-informed maternal mortality review committee can provide. Data collection and analysis, clinical factors, preventability, social determinants of health, and racial inequities combine to affect this outcome, and each factor must be considered individually and in combination to recommend a robust response. Obstetrician-gynecologists formed the State of Michigan's Maternal Mortality Review Committee (the Committee) in 1950 to identify gaps in care that needed to be systematically addressed at the time. In the early years, the Committee witnessed a reduction in the number of maternal deaths; over time, prioritization of maternal mortality decreased, yet the Committee witnessed changing patterns of death, varied data collection and evaluation processes, delayed reviews, and unimplemented recommendations. The calculation of the maternal mortality ratio was not informed by the outcomes of Committee reviews. Today, the Committee, with increased support from the Michigan Department of Health & Human Services, can clearly identify and report preventable pregnancy-related mortality along with its causes and is close to achieving a near real-time surveillance system that allows the development of timely clinical and policy recommendations and interventions. The Committee's adaptations in response to the rise in maternal mortality have resulted in several lessons learned that may be helpful for currently operating committees and in the formation of new ones.


Assuntos
Uso Indevido de Medicamentos , Mortalidade Materna/tendências , Complicações na Gravidez , Serviços Preventivos de Saúde , Melhoria de Qualidade , Prevenção do Suicídio , Suicídio , Adulto , Comitês Consultivos/normas , Comitês Consultivos/estatística & dados numéricos , Uso Indevido de Medicamentos/mortalidade , Uso Indevido de Medicamentos/prevenção & controle , Falha da Terapia de Resgate/estatística & dados numéricos , Feminino , Disparidades em Assistência à Saúde/normas , Humanos , Michigan/epidemiologia , Mortalidade , Gravidez , Complicações na Gravidez/mortalidade , Complicações na Gravidez/prevenção & controle , Serviços Preventivos de Saúde/métodos , Serviços Preventivos de Saúde/normas , Melhoria de Qualidade/organização & administração , Melhoria de Qualidade/tendências , Determinantes Sociais da Saúde/etnologia , Suicídio/estatística & dados numéricos
12.
J Mol Evol ; 88(5): 463-472, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32388714

RESUMO

The colonization of freshwater habitats by marine-adapted organisms represents a major transition that has only occurred a few times in the evolution of animals. Only around half of the extant animal phyla have representatives in both marine and freshwater environments and even within those phyla some major clades are restricted to marine environments. Moving from marine to freshwater environments can create severe osmotic and ionic stresses and the mechanisms that animals have used to adapt to those stresses are still not well understood. In this study, we downloaded amino acid sequence data from 11 spiralian animal genomes (four freshwater taxa representing four different phyla as well as 7 marine taxa) and identified a number of gene family expansions that have occurred exclusively in the freshwater lineages. Further investigation of these gene families and the timing and nature of their expansions will illuminate one of the major evolutionary transitions in the history of life on Earth.


Assuntos
Evolução Biológica , Ecossistema , Água Doce , Invertebrados/genética , Adaptação Fisiológica , Animais , Genoma , Família Multigênica , Filogenia
13.
Mol Phylogenet Evol ; 147: 106801, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32217167

RESUMO

The wide disparity in adult body size observed both within and among animal taxa has long attracted widespread interest, with several general rules having been proposed to explain trends in body size evolution. Adult body size disparity among the cephalopod mollusks is remarkable, with adult body sizes ranging from a few centimeters to several meters. Some of the smallest cephalopods are found within Pickfordiateuthis, a group comprising three described species of squid found in the western Atlantic and tropical eastern Pacific. Pickfordiateuthis pulchella, the type species of the genus, was initially proposed to be closely related to the loliginid squids (Loliginidae), with subsequent descriptions of additional species supporting a placement within Loliginidae. Pickfordiateuthis is remarkable in that all species reach sexual maturity at about one-fifth to one-tenth the size seen in most loliginid species. To date, no phylogenetic analyses have included representatives of Pickfordiateuthis. To infer the phylogenetic position of Pickfordiateuthis and explore its implications for body size evolution, we collected specimens of Pickfordiateuthis pulchella from Brazilian waters and sequenced regions of two loci-the mitochondrial large ribosomal subunit (rrnL a.k.a. 16S) gene and the nuclear gene rhodopsin. Maximum likelihood and Bayesian analyses of these sequences support a placement of Pickfordiateuthis pulchella as sister to a clade comprising the Western Hemisphere loliginid genera Doryteuthis and Lolliguncula. Analyses of body size evolution within Loliginidae suggest that a shift to a smaller body size optimum occurred along the lineage leading to P. pulchella, with some evidence of shifts toward larger sizes in the ancestors of Loligo and Sepioteuthis; these inferences seem to be robust to phylogenetic uncertainty and incomplete taxon sampling. The small size and juvenile-like morphological traits seen in adult Pickfordiateuthis (e.g., sepiolid-like fins and biserial sucker arrangement in the tentacles) may be due to paedomorphosis.


Assuntos
Decapodiformes/classificação , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , Brasil , Simulação por Computador
14.
Atmosphere (Basel) ; 10(6)2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31803514

RESUMO

Wildland fire smoke exposure affects a broad proportion of the U.S. population and is increasing due to climate change, settlement patterns and fire seclusion. Significant public health questions surrounding its effects remain, including the impact on cardiovascular disease and maternal health. Using atmospheric chemical transport modeling, we examined general air quality with and without wildland fire smoke PM2.5. The 24-h average concentration of PM2.5 from all sources in 12-km gridded output from all sources in California (2007-2013) was 4.91 µg/m3. The average concentration of fire-PM2.5 in California by year was 1.22 µg/m3 (~25% of total PM2.5). The fire-PM2.5 daily mean was estimated at 4.40 µg/m3 in a high fire year (2008). Based on the model-derived fire-PM2.5 data, 97.4% of California's population lived in a county that experienced at least one episode of high smoke exposure ("smokewave") from 2007-2013. Photochemical model predictions of wildfire impacts on daily average PM2.5 carbon (organic and elemental) compared to rural monitors in California compared well for most years but tended to over-estimate wildfire impacts for 2008 (2.0 µg/m3 bias) and 2013 (1.6 µg/m3 bias) while underestimating for 2009 (-2.1 µg/m3 bias). The modeling system isolated wildfire and PM2.5 from other sources at monitored and unmonitored locations, which is important for understanding population exposure in health studies. Further work is needed to refine model predictions of wildland fire impacts on air quality in order to increase confidence in the model for future assessments. Atmospheric modeling can be a useful tool to assess broad geographic scale exposure for epidemiologic studies and to examine scenario-based health impacts.

16.
Genome Biol Evol ; 11(11): 3082-3093, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31214691

RESUMO

Leeches (Hirudinida) comprise a charismatic, yet often maligned group of organisms. Despite their ecological, economic, and medical importance, a general consensus on the phylogenetic relationships of major hirudinidan lineages is lacking. This absence of a consistent, robust phylogeny of early-diverging lineages has hindered our understanding of the underlying processes that enabled evolutionary diversification of this clade. Here, we used an anchored hybrid enrichment-based phylogenomic approach, capturing hundreds of loci to investigate phylogenetic relationships among major hirudinidan lineages and their closest living relatives. Our results suggest that a dramatic reinterpretation of early leech evolution is warranted. We recovered Branchiobdellida as sister to a clade that includes all major lineages of hirudinidans, but found Acanthobdella to be nested within Oceanobdelliformes. These results cast doubt on the utility of Acanthobdella as a "missing link" used to explain the origin of blood-feeding in hirudineans. Further, our results support a deep divergence between predominantly marine and freshwater lineages, while not supporting the reciprocal monophyly of jawed and proboscis-bearing leeches. To sum up, our phylogenomic resolution of early-diverging leeches provides a necessary foundation for illuminating the evolution of host-symbiont associations and key adaptations that have allowed leeches to colonize a wide diversity of habitats worldwide.


Assuntos
Sanguessugas/genética , Animais , Filogenia , Análise de Sequência de DNA , Simbiose/genética , Simbiose/fisiologia
17.
J Evol Biol ; 32(6): 580-591, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30860304

RESUMO

Major habitat transitions, such as those from marine to freshwater habitats or from aquatic to terrestrial habitats, have occurred infrequently in animal evolution and may represent a barrier to diversification. Identifying genomic events associated with these transitions can help us better understand mechanisms that allow animals to cross these barriers and diversify in new habitats. Study of the Capitella telata and Helobdella robusta genomes allows examination of one such habitat transition (marine to freshwater) in Annelida. Initial examination of these genomes indicated that the freshwater leech H. robusta contains many more copies (12) of the sodium-potassium pump alpha-subunit (Na+ /K+ -ATPase) gene than does the marine polychaete C. telata (2). The sodium-potassium pump plays a key role in maintenance of cellular ionic balance and osmoregulation, and Na+ /K+ -ATPase duplications may have helped annelids invade and diversify in freshwater habitats. To assess whether the timing of Na+ /K+ -ATPase duplications coincided with the marine-to-freshwater transition in Clitellata, we used transcriptomic data from 18 annelid taxa, along with the two genomes, to infer a species phylogeny and identified Na+ /K+ -ATPase gene transcripts in order to infer the timing of gene duplication events using tree-based methods. The inferred timing of Na+ /K+ -ATPase duplication events is consistent with the timing of the initial marine-to-freshwater transition early in the history of clitellate annelids, supporting the hypothesis that gene duplications may have played a role in the annelid diversification into freshwater habitats.


Assuntos
Duplicação Gênica , Sanguessugas/genética , Filogenia , ATPase Trocadora de Sódio-Potássio/genética , Animais , Ecossistema , Genoma , Família Multigênica
18.
Am J Bot ; 106(3): 402-414, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30856677

RESUMO

PREMISE OF THE STUDY: The sandalwood order (Santalales) includes members that present a diverse array of inflorescence types, some of which are unique among angiosperms. This diversity presents not only interpretational challenges but also opportunities to test fundamental concepts in plant morphology. Here we used modern phylogenetic approaches to address the evolution of inflorescences in the sandalwood order. METHODS: Phylogenetic analyses of two nuclear and three chloroplast genes were conducted on representatives of 146 of the 163 genera in the order. A matrix was constructed that scored nine characters dealing with inflorescences. One character, "trios", that encompasses any grouping of three flowers (i.e., both dichasia and triads) was optimized on samples of the posterior distribution of trees from the Bayesian analysis using BayesTraits. Three nodes were examined: the most recent common ancestors of (A) all ingroup members, (B) Loranthaceae, and (C) Opiliaceae, Santalaceae s.l., and Viscaceae. KEY RESULTS: The phylogenetic analysis resulted in many fully resolved nodes across Santalales with strong support for 18 clades previously named as families. The trios character was not supported for nodes A and C, whereas it was supported for node B where this partial inflorescence type is best described as a triad. CONCLUSIONS: Essentially every major inflorescence type can be found in Santalales; however, the dichasium, a type of partial inflorescence, is rarely seen and is not plesiomorphic for the order. In the family Erythropalaceae, inflorescences are mostly in small, axillary fascicles or cymes. Successive families show both cymose and racemose types and compound systems (e.g., thyrses). Inflorescences in Amphorogynaceae and Viscaceae are not dichasial and in general are difficult to compare to "standard" inflorescences.


Assuntos
Evolução Biológica , Inflorescência/anatomia & histologia , Loranthaceae/anatomia & histologia , Santalaceae/anatomia & histologia , Viscaceae/anatomia & histologia , Evolução Molecular , Loranthaceae/genética , Filogenia , Santalaceae/genética , Viscaceae/genética
19.
Mol Phylogenet Evol ; 128: 212-220, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30099062

RESUMO

Stenonema, Stenacron, and Maccaffertium are three closely related genera of mayflies (Ephemeroptera:Heptageniidae) commonly found across North America. Due to their primarily aquatic life history and sensitivity to aquatic pollutants, these mayflies are often used as water quality indicators. However, there is little morphological variation within these genera, leading to difficulties in identification and rampant taxonomic confusion, limiting their utility as bioindicators. In an attempt to resolve the phylogenetic relationships of Stenonema, Stenacron, and Maccaffertium, and to clarify their higher-level classifications, we sequenced regions of two mitochondrial genes (cytochrome oxidase subunit 1 (cox1) and 16S ribosomal RNA (rrnl)) and two nuclear genes (Wingless (Wg) and histone H3) from 60 individuals representing most of the described species in these genera and included data from representatives of three heptageniid genera (Kageronia, Macdunnoa and Pseudiron) proposed in previous studies to be closely related to our focal taxa as well as two more distantly related heptageniid genera (Epeorus and Heptagenia) to root the phylogenies. Maximum likelihood and Bayesian analysis were conducted on single-gene and concatenated multi-gene data sets and species tree methods were utilized to resolve relationships. These analyses resolved Stenacron as a monophyletic group sister to a clade comprising Macdunnoa, Maccaffertium and Stenonema. Maccaffertium was found to be paraphyletic, with Stenonema femoratum resolved within Maccaffertium as sister to M. mexicanum. Many relationships remained unresolved or varied across analyses, making revision of the classification based on phylogenetic considerations challenging. To minimize confusion while naming clades and acknowledging uncertainty in our phylogenetic conclusions, we redefine Stenonema to include Maccaffertium and propose three subgenera-Stenonema, Maccaffertium and Lewisa- for key well-supported clades.


Assuntos
Ephemeroptera/classificação , Filogenia , Animais , Teorema de Bayes , Funções Verossimilhança , Análise de Sequência de DNA , Estados Unidos
20.
Matern Child Health J ; 22(7): 1085-1091, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29520728

RESUMO

Introduction To provide a qualitative perspective on the changes that occurred after newly placed OB/GYNs began working at district hospitals in Ashanti, Ghana. Methods Structured interviews of healthcare professionals were conducted at eight district hospitals located throughout the Ashanti district of Ghana, four with and four without a full-time OB/GYN on staff. Individuals interviewed include: medical superintendents, medical officers, district hospital administrators, OB/GYNs (where applicable), and nurse-midwives. Interviews were transcribed verbatim and content analysis was performed to identify common themes. Characteristics quotes were identified to illustrate principal interview themes. Quotes were verified in context by researchers for accuracy. Results Interviews with providers revealed four areas most impacted by an OB/GYN's leadership and expertise at district hospitals: patient referral patterns, obstetric protocol and training, facility management and organization, and hospital reputation. Discussion OB/GYNs are uniquely positioned to add clinical capacity and care quality to established maternal care teams at district hospitals-empowering district hospitals as reliable care centers throughout rural Ghana for women's health. Coordinated efforts between government, donors and OBGYN training institutions to provide complete obstetric teams is the next step to achieve the global goal of eliminating preventable maternal mortality by 2030.


Assuntos
Hospitais de Distrito/organização & administração , Serviços de Saúde Materna/organização & administração , Obstetrícia , Melhoria de Qualidade , Qualidade da Assistência à Saúde , Adulto , Fortalecimento Institucional , Feminino , Gana , Humanos , Entrevistas como Assunto , Gravidez , Pesquisa Qualitativa , População Rural
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