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1.
J Med Humanit ; 44(4): 503-531, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37526858

RESUMO

This paper offers a novel, qualitative approach to evaluating the outcomes of integrating humanities and ethics into a newly revised pre-clerkship medical education curriculum. The authors set out to evaluate medical students' perceptions, learning outcomes, and growth in identity development. Led by a team of interdisciplinary scholars, this qualitative project examines multiple sources of student experience and perception data, including student essays, end-of-year surveys, and semi-structured interviews with students. Data were analyzed using deductive and inductive processes to identify key categories and recurring themes. Results suggest that students not only engaged with the curricular content and met the stated learning objectives but also acknowledged their experience in the humanities and ethics curriculum as an opportunity to reflect, expand their perceptions of medicine (and what it means to be "in" medicine), connect with their classmates, and further cultivate their personal and professional identities. Results of this qualitative study show how and in what ways the ethics and humanities curriculum motivates students past surface-level memorization of factual knowledge and encourages thoughtful analysis and evaluation about how the course material relates to and influences their thinking and how they see themselves as future doctors. The comprehensive qualitative approach reflects a holistic model for evaluating the integration of humanities and ethics into the pre-clerkship medical education curriculum. Future research should examine if this approach provides a protective factor against the demonstrated ethical erosion and empathy decrease during clinical training.


Assuntos
Educação Médica , Médicos , Estudantes de Medicina , Humanos , Ciências Humanas/educação , Currículo , Aprendizagem , Ética Médica
2.
Polymers (Basel) ; 14(5)2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35267713

RESUMO

An innovative and sustainable approach to integrating modified Ag-MgO-nanohydroxyapatite on a nanofibrous cellulose template (CNF-AgMgOnHaP) as a multifunctional adsorbent via a hydrothermal bioreduction route using Citrus paradisi peel extract was developed and examined. The surface morphology and mineralogical properties of CNF-AgMgOnHaP by UV-vis spectroscopy, SEM-EDS, XRD, FTIR, TEM, and BET techniques are reported. Batch fluoride sorption studies and its disinfection potential against common bacteria in surface water were evaluated. The results showed the successful synthesis of a modified multistructural CNF-AgMgOnHaP composite with an improved BET surface area of 160.17 m2/g. The sorption of fluoride by the adsorbent was found to strongly depend on the different sorption conditions with a maximum F- sorption capacity of 8.71 mg/g at 303 K, and pH of 5 with 0.25 g dosage at 10 min contact time (25 ± 3 °C). Equilibrium fluoride sorption onto the CNF-AgMgOnHaP was best described by the Freundlich isotherm model across all the operating temperatures. The overall kinetic results showed that the adsorption mechanisms not only depend on using the pseudo-second-order process but are also governed by the mass transfer of the adsorbate molecules from the external surface onto the pores of the adsorbent. The thermodynamic parameters revealed that the adsorption process of F- onto CNF-AgMgOnHaP was endothermic and spontaneous at the sorbent/solution interface. The synthesized composite also provides some antibacterial activity against common infectious microbes from contaminated drinking water. The overall results suggested that the CNF-AgMgOnHaP nanocomposite possesses the potential for the simultaneous decontamination of pollutants and microbes in drinking water.

3.
Fertil Steril ; 116(4): 973-979, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34289935

RESUMO

OBJECTIVE: To determine the association between vitamin D levels in the male partner and fertility outcomes in couples with mild male factor infertility. DESIGN: Secondary analysis of a randomized, controlled trial. SETTING: Nine fertility centers in the United States. PATIENT(S): Men (n = 154) with sperm concentration between 5 and 15 million/mL, motility ≤40%, or normal morphology ≤4% were eligible. Female partners were ovulatory, ≤40 years old, and had documented tubal patency. INTERVENTION(S): Men provided semen and blood at baseline for semen analysis and 25-hydroxyvitamin D (25(OH)D) levels. They were randomly assigned to receive a vitamin formulation including vitamin D 2,000 IU daily or placebo for up to 6 months. Couples attempted to conceive naturally during the first 3 months and with clomiphene citrate with intrauterine insemination of the female partner in months 4 through 6. MAIN OUTCOME MEASURE(S): Primary: sperm concentration, motility, morphology, and DNA fragmentation at baseline. Secondary: cumulative pregnancy, miscarriage, and live birth rates. RESULT(S): Semen parameters and sperm DNA fragmentation were not statistically significantly different between men with vitamin D deficiency and men with 25(OH)D levels ≥20 ng/mL. In addition, clinical pregnancy and live birth rates were similar. Male 25(OH)D level <20 ng/mL was associated with a higher rate of pregnancy loss (adjusted odds ratio 9.0; 95% confidence interval 1.3 to 61.3). CONCLUSION(S): Vitamin D deficiency in the male partner did not significantly impact semen parameters or treatment outcomes. Further study is warranted to better characterize the rate of miscarriage in couples with male vitamin D deficiency.


Assuntos
Clomifeno/uso terapêutico , Fármacos para a Fertilidade Feminina/uso terapêutico , Fertilidade , Infertilidade Masculina/terapia , Inseminação Artificial Homóloga , Deficiência de Vitamina D/sangue , Vitamina D/análogos & derivados , Aborto Espontâneo/etiologia , Adulto , Biomarcadores/sangue , Clomifeno/efeitos adversos , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Fertilidade/efeitos dos fármacos , Fármacos para a Fertilidade Feminina/efeitos adversos , Humanos , Infertilidade Masculina/sangue , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/fisiopatologia , Inseminação Artificial Homóloga/efeitos adversos , Nascido Vivo , Masculino , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Fatores de Risco , Sêmen/metabolismo , Análise do Sêmen , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Vitamina D/sangue , Vitamina D/uso terapêutico , Deficiência de Vitamina D/diagnóstico , Deficiência de Vitamina D/tratamento farmacológico
4.
JCI Insight ; 6(8)2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33705358

RESUMO

Currently, no effective therapies exist for fibrodysplasia ossificans progressiva (FOP), a rare congenital syndrome in which heterotopic bone is formed in soft tissues owing to dysregulated activity of the bone morphogenetic protein (BMP) receptor kinase ALK2 (also known as ACVR1). From a screen of known biologically active compounds, we identified saracatinib as a potent ALK2 kinase inhibitor. In enzymatic and cell-based assays, saracatinib preferentially inhibited ALK2, compared with other receptors of the BMP/TGF-ß signaling pathway, and induced dorsalization in zebrafish embryos consistent with BMP antagonism. We further tested the efficacy of saracatinib using an inducible ACVR1Q207D-transgenic mouse line, which provides a model of heterotopic ossification (HO), as well as an inducible ACVR1R206H-knockin mouse, which serves as a genetically and physiologically faithful FOP model. In both models, saracatinib was well tolerated and potently inhibited the development of HO, even when administered transiently following soft tissue injury. Together, these data suggest that saracatinib is an efficacious clinical candidate for repositioning in FOP treatment, offering an accelerated path to clinical proof-of-efficacy studies and potentially significant benefits to individuals with this devastating condition.


Assuntos
Receptores de Ativinas Tipo I/genética , Benzodioxóis/farmacologia , Proteínas Morfogenéticas Ósseas/efeitos dos fármacos , Músculos/efeitos dos fármacos , Miosite Ossificante/genética , Quinazolinas/farmacologia , Receptores de Ativinas Tipo I/antagonistas & inibidores , Animais , Benzodioxóis/uso terapêutico , Proteínas Morfogenéticas Ósseas/metabolismo , Avaliação Pré-Clínica de Medicamentos , Técnicas de Introdução de Genes , Camundongos , Camundongos Transgênicos , Músculos/metabolismo , Miosite Ossificante/metabolismo , Miosite Ossificante/patologia , Ossificação Heterotópica/genética , Ossificação Heterotópica/metabolismo , Ossificação Heterotópica/patologia , Quinazolinas/uso terapêutico , Peixe-Zebra
5.
Regul Toxicol Pharmacol ; 120: 104857, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33387566

RESUMO

Pharmaceutical and biotechnology companies rarely disclose their use of translational emerging safety biomarkers (ESBs) during drug development, and the impact of ESB use on the speed of drug development remains unclear. A cross-industry survey of 20 companies of varying size was conducted to understand current trends in ESB use and future use prospects. The objectives were to: (1) determine current ESB use in nonclinical and clinical drug development and impact on asset advancement; (2) identify opportunities, gaps, and challenges to greater ESB implementation; and (3) benchmark perspectives on regulatory acceptance. Although ESBs were employed in only 5-50% of studies/programs, most companies used ESBs to some extent, with larger companies demonstrating greater nonclinical use. Inclusion of ESBs in investigational new drug applications (INDs) was similar across all companies; however, differences in clinical trial usage could vary among the prevailing health authority (HA). Broader implementation of ESBs requires resource support, cross-industry partnerships, and collaboration with HAs. This includes generating sufficient foundational data, demonstrating nonclinical to clinical translatability and practical utility, and clearly written criteria by HAs to enable qualification. If achieved, ESBs will play a critical role in the development of next-generation, translationally-tailored standard laboratory tests for drug development.


Assuntos
Biomarcadores Farmacológicos/metabolismo , Ensaios Clínicos como Assunto/normas , Indústria Farmacêutica/normas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/metabolismo , Inquéritos e Questionários , Animais , Ensaios Clínicos como Assunto/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/normas , Indústria Farmacêutica/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Previsões , Humanos , Preparações Farmacêuticas/metabolismo , Distribuição Tecidual/efeitos dos fármacos , Distribuição Tecidual/fisiologia
6.
Nature ; 580(7801): 81-86, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32238944

RESUMO

The mid-Cretaceous period was one of the warmest intervals of the past 140 million years1-5, driven by atmospheric carbon dioxide levels of around 1,000 parts per million by volume6. In the near absence of proximal geological records from south of the Antarctic Circle, it is disputed whether polar ice could exist under such environmental conditions. Here we use a sedimentary sequence recovered from the West Antarctic shelf-the southernmost Cretaceous record reported so far-and show that a temperate lowland rainforest environment existed at a palaeolatitude of about 82° S during the Turonian-Santonian age (92 to 83 million years ago). This record contains an intact 3-metre-long network of in situ fossil roots embedded in a mudstone matrix containing diverse pollen and spores. A climate model simulation shows that the reconstructed temperate climate at this high latitude requires a combination of both atmospheric carbon dioxide concentrations of 1,120-1,680 parts per million by volume and a vegetated land surface without major Antarctic glaciation, highlighting the important cooling effect exerted by ice albedo under high levels of atmospheric carbon dioxide.


Assuntos
Atmosfera/química , Dióxido de Carbono/análise , Dióxido de Carbono/história , Clima , Floresta Úmida , Temperatura , Regiões Antárticas , Fósseis , Sedimentos Geológicos/química , História Antiga , Modelos Teóricos , Nova Zelândia , Pólen , Esporos/isolamento & purificação
7.
Mayo Clin Proc ; 94(6): 976-984, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31171135

RESUMO

OBJECTIVE: To compare diagnostic accuracy between primary care E-Visit and face-to-face (F2F) encounters for low-acuity illnesses. PATIENTS AND METHODS: This cross-sectional retrospective analysis of electronic health records in a large not-for-profit integrated delivery system included patients covered by the health care system's employee health plan with an established affiliated physician-patient relationship and an F2F encounter in the past 12 months who had an E-Visit (n=490) or an F2F (n=2201) primary care encounter for a low-acuity illness from July 1, 2015, through December 22, 2016. Patients with a related follow-up visit within 10 days resulting in a revised diagnosis, as determined by 2 physician reviewers, were compared (1) including only the first encounter for each patient and (2) including all encounters more than 10 days apart for included patients. RESULTS: In both analyses, a follow-up visit occurred within 10 days more than 40% of the time in both groups. However, follow-up visits related to the initial diagnosis occurred only 9% to 12% of the time. Only 2.1% to 2.4% of initial diagnoses were identified by both physician reviewers as revised, whereas 3.8% to 5.5% were so identified by at least 1 reviewer. The only significant difference observed between the E-Visit and F2F groups was in the rate of related follow-up visits when only each patient's first encounter was considered, which was higher for E-Visits (12% vs 9%; P=.04). CONCLUSION: Diagnostic accuracy for low-acuity illnesses in this population was equivalent between E-Visit and F2F encounters.


Assuntos
Prestação Integrada de Cuidados de Saúde , Preferência do Paciente , Relações Médico-Paciente , Atenção Primária à Saúde/tendências , Consulta Remota , Adulto , Estudos Transversais , Registros Eletrônicos de Saúde , Feminino , Humanos , Masculino , Estudos Retrospectivos
8.
J Pharmacol Toxicol Methods ; 98: 106579, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31085319

RESUMO

This meeting report is based on presentations given at the first Drug Safety Africa Meeting in Potchefstroom, South Africa from November 20-22, 2018 at the North-West University campus. There were 134 attendees (including 26 speakers and 34 students) from the pharmaceutical industry, academia, regulatory agencies as well as 6 exhibitors. These meeting proceedings are designed to inform the content that was presented in terms of Safety Pharmacology (SP) and Toxicology methods and models that are used by the pharmaceutical industry to characterize the safety profile of novel small chemical or biological molecules. The first part of this report includes an overview of the core battery studies defined by cardiovascular, central nervous system (CNS) and respiratory studies. Approaches to evaluating drug effects on the renal and gastrointestinal systems and murine phenotyping were also discussed. Subsequently, toxicological approaches were presented including standard strategies and options for early identification and characterization of risks associated with a novel therapeutic, the types of toxicology studies conducted and relevance to risk assessment supporting first-in-human (FIH) clinical trials and target organ toxicity. Biopharmaceutical development and principles of immunotoxicology were discussed as well as emerging technologies. An additional poster session was held that included 18 posters on advanced studies and topics by South African researchers, postgraduate students and postdoctoral fellows.


Assuntos
Produtos Biológicos/toxicidade , Indústria Farmacêutica/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Medição de Risco/métodos , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Farmacologia/métodos , África do Sul , Toxicologia/métodos
10.
JAMA Oncol ; 5(4): e185896, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30629084

RESUMO

IMPORTANCE: The watch-and-wait (WW) strategy aims to spare patients with rectal cancer unnecessary resection. OBJECTIVE: To analyze the outcomes of WW among patients with rectal cancer who had a clinical complete response to neoadjuvant therapy. DESIGN, SETTING, AND PARTICIPANTS: This retrospective case series analysis conducted at a comprehensive cancer center in New York included patients who received a diagnosis of rectal adenocarcinoma between January 1, 2006, and January 31, 2015. The median follow-up was 43 months. Data analyses were conducted from June 1, 2016, to October 1, 2018. EXPOSURES: Patients had a clinical complete response after completing neoadjuvant therapy and agreed to a WW strategy of active surveillance and possible salvage surgery (n = 113), or patients underwent total mesorectal excision and were found to have a pathologic complete response (pCR) at resection (n = 136). MAIN OUTCOMES AND MEASURES: Kaplan-Meier estimates were used for analyses of local regrowth and 5-year rates of overall survival, disease-free survival, and disease-specific survival. RESULTS: Compared with the 136 patients in the pCR group, the 113 patients in the WW group were older (median [range], 67.2 [32.1-90.9] vs 57.3 [25.0-87.9] years, P < .001) with cancers closer to the anal verge (median [range] height from anal verge, 5.5 [0.0-15.0] vs 7.0 [0.0-13.0] cm). All 22 local regrowths in the WW group were detected on routine surveillance and treated by salvage surgery (20 total mesorectal excisions plus 2 transanal excisions). Pelvic control after salvage surgery was maintained in 20 of 22 patients (91%). No pelvic recurrences occurred in the pCR group. Rectal preservation was achieved in 93 of 113 patients (82%) in the WW group (91 patients with no local regrowths plus 2 patients with local regrowths salvaged with transanal excision). At 5 years, overall survival was 73% (95% CI, 60%-89%) in the WW group and 94% (95% CI, 90%-99%) in the pCR group; disease-free survival was 75% (95% CI, 62%-90%) in the WW group and 92% (95% CI, 87%-98%) in the pCR group; and disease-specific survival was 90% (95% CI, 81%-99%) in the WW group and 98% (95% CI, 95%-100%) in the pCR group. A higher rate of distant metastasis was observed among patients in the WW group who had local regrowth vs those who did not have local regrowth (36% vs 1%, P < .001). CONCLUSIONS AND RELEVANCE: A WW strategy for select rectal cancer patients who had a clinical complete response after neoadjuvant therapy resulted in excellent rectal preservation and pelvic tumor control; however, in the WW group, worse survival was noted along with a higher incidence of distant progression in patients with local regrowth vs those without local regrowth.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais/terapia , Conduta Expectante , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Indução de Remissão , Estudos Retrospectivos , Resultado do Tratamento
11.
J Contam Hydrol ; 208: 35-45, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29224929

RESUMO

The use of ethanol in alternative fuels has led to contamination of groundwater with high concentrations of this easily biodegradable organic compound. Previous laboratory and field studies have shown vigorous biodegradation of ethanol plumes, with prevalence of reducing conditions and methanogenesis. The objective of this study was to further our understanding of the dynamic biogeochemistry processes, especially dissolved gas production, that may occur in developing and aging plume cores at sites with ethanol or other organic contamination of groundwater. The experiment performed involved highly-detailed spatial and temporal monitoring of ethanol biodegradation in a 2-dimensional (175cm high×525cm long) sand aquifer tank for 330days, with a vertical shift in plume position and increased nutrient inputs occurring at ~Day 100. Rapid onset of fermentation, denitrification, sulphate-reduction and iron(III)-reduction occurred following dissolved ethanol addition, with the eventual widespread development of methanogenesis. The detailed observations also demonstrate a redox zonation that supports the plume fringe concept, secondary reactions resulting from a changing/moving plume, and time lags for the various biodegradation processes. Additional highlights include: i) the highest dissolved H2 concentrations yet reported for groundwater, possibly linked to vigorous fermentation in the absence of common terminal electron-acceptors (i.e., dissolved oxygen, nitrate, and sulphate, and iron(III)-minerals) and methanogenesis; ii) evidence of phosphorus nutrient limitation, which stalled ethanol biodegradation and perhaps delayed the onset of methanogenesis; and iii) the occurrence of dissimilatory nitrate reduction to ammonium, which has not been reported for ethanol biodegradation to date.


Assuntos
Etanol/metabolismo , Água Subterrânea , Poluentes Químicos da Água/metabolismo , Compostos de Amônio/metabolismo , Biodegradação Ambiental , Etanol/análise , Fermentação , Água Subterrânea/química , Hidrogênio/análise , Hidrogênio/metabolismo , Ferro/química , Ferro/metabolismo , Oxirredução , Fósforo/metabolismo , Dióxido de Silício , Análise Espaço-Temporal , Sulfatos/química , Sulfatos/metabolismo , Poluentes Químicos da Água/análise
12.
Toxicol Pathol ; 45(7): 894-903, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29113558

RESUMO

Although the brain is well established as a master regulator of homeostasis in peripheral tissues, central regulation of bone mass represents a novel and rapidly expanding field of study. This review examines the current understanding of central regulation of the skeleton, exploring several of the key pathways connecting brain to bone and their implications both in mice and the clinical setting. Our understanding of central bone regulation has largely progressed through examination of skeletal responses downstream of nutrient regulatory pathways in the hypothalamus. Mutations and modulation of these pathways, in cases such as leptin deficiency, induce marked bone phenotypes, which have provided vital insights into central bone regulation. These studies have identified several central neuropeptide pathways that stimulate well-defined changes in bone cell activity in response to changes in energy homeostasis. In addition, this work has highlighted the endocrine nature of the skeleton, revealing a complex cross talk that directly regulates other organ systems. Our laboratory has studied bone-active neuropeptide pathways and defined osteoblast-based actions that recapitulate central pathways linking bone, fat, and glucose homeostasis. Studies of neural control of bone have produced paradigm-shifting changes in our understanding of the skeleton and its relationship with the wider array of organ systems.


Assuntos
Remodelação Óssea , Neurônios/fisiologia , Animais , Osso e Ossos/fisiologia , Homeostase , Humanos , Hipotálamo/fisiologia , Leptina/fisiologia , Músculo Esquelético/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Neuropeptídeo Y/fisiologia , Polipeptídeo Pancreático/fisiologia , Peptídeo YY/fisiologia , Pró-Opiomelanocortina/fisiologia , Receptores de Canabinoides/fisiologia , Semaforinas/fisiologia , Sistema Nervoso Simpático/fisiologia
13.
Toxicol Appl Pharmacol ; 320: 1-7, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28167222

RESUMO

The human testis is sensitive to toxicant-induced injury but current methods for detecting adverse effects are limited, insensitive and unreliable. Animal studies use sensitive histopathological endpoints to assess toxicity, but require testicular tissue that is not available during human clinical trials. More sensitive and reliable molecular biomarkers of testicular injury are needed to better monitor testicular toxicity in both clinical and preclinical. Adult male Wistar Han rats were exposed for 4weeks to compounds previously associated with testicular injury, including cisplatin (0, 0.2, 0.3, or 0.4mg/kg/day), BI665915 (0, 20, 70, 100mg/kg/d), BI665636 (0, 20, 100mg/kg/d) or BI163538 (0, 70, 150, 300mg/kg/d) to evaluate reproductive toxicity and assess changes in sperm mRNA levels. None of the compounds resulted in any significant changes in body, testis or epididymis weights, nor were there decreases in testicular homogenization resistant spermatid head counts. Histopathological evaluation found that only BI665915 treatment caused any testicular effects, including minor germ cell loss and disorganization of the seminiferous tubule epithelium, and an increase in the number of retained spermatid heads. A custom PCR-array panel was used to assess induced changes in sperm mRNA. BI665915 treatment resulted in a significant increase in clusterin (Clu) levels and decreases in GTPase, IMAP family member 4 (Gimap4), prostaglandin D2 synthase (Ptgds) and transmembrane protein with EGF like and two follistatin like domains 1 (Tmeff1) levels. Correlation analysis between transcript levels and quantitative histopathological endpoints found a modest association between Clu with retained spermatid heads. These results demonstrate that sperm mRNA levels are sensitive molecular indicators of testicular injury that can potentially be translated into a clinical setting.


Assuntos
Acetamidas/toxicidade , Cisplatino/toxicidade , Oxidiazóis/toxicidade , RNA Mensageiro/biossíntese , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo , Animais , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Tamanho do Órgão/fisiologia , Ratos , Ratos Wistar , Espermatogênese/efeitos dos fármacos , Espermatogênese/fisiologia , Espermatozoides/patologia , Testículo/patologia
14.
BMC Plant Biol ; 16(1): 174, 2016 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-27488358

RESUMO

BACKGROUND: Chlorophyll is a major component of chloroplasts and a better understanding of the genetic basis of chlorophyll in soybean [Glycine max (L.) Merr.] might contribute to improving photosynthetic capacity and yield in regions with adverse environmental conditions. A collection of 332 diverse soybean genotypes were grown in 2 years (2009 and 2010) and chlorophyll a (eChl_A), chlorophyll b (eChl_B), and total chlorophyll (eChl_T) content as well as chlorophyll a/b ratio (eChl_R) in leaf tissues were determined by extraction and spectrometric determination. Total chlorophyll was also derived from canopy spectral reflectance measurements using a model of wavelet transformed spectra (tChl_T) as well as with a spectral reflectance index (iChl_T). RESULTS: A genome-wide associating mapping approach was employed using 31,253 single nucleotide polymorphisms (SNPs) to identify loci associated with the extract based eChl_A, eChl_B, eChl_R and eChl_T measurements and the two canopy spectral reflectance-based methods (tChl_T and iChl_T). A total of 23 (14 loci), 15 (7 loci) and 14 SNPs (10 loci) showed significant association with eChl_A, eChl_B and eChl_R respectively. A total of 52 unique SNPs were significantly associated with total chlorophyll content based on at least one of the three approaches (eChl_T, tChl_T and iChl_T) and likely tagged 27 putative loci for total chlorophyll content, four of which were indicated by all three approaches. CONCLUSIONS: Results presented here show that markers for chlorophyll traits can be identified in soybean using both extract-based and canopy spectral reflectance-based phenotypes, and confirm that high-throughput phenotyping-amenable canopy spectral reflectance measurements can be used for association mapping.


Assuntos
Clorofila/química , Glycine max/genética , Extratos Vegetais/química , Folhas de Planta/química , Clorofila/genética , Clorofila/metabolismo , Estudo de Associação Genômica Ampla , Genótipo , Extratos Vegetais/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único , Glycine max/química , Glycine max/metabolismo
15.
Science ; 352(6285): 555-9, 2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-26989199

RESUMO

Steroids regulate cell proliferation, tissue development, and cell signaling via two pathways: a nuclear receptor mechanism and genome-independent signaling. Sperm activation, egg maturation, and steroid-induced anesthesia are executed via the latter pathway, the key components of which remain unknown. Here, we present characterization of the human sperm progesterone receptor that is conveyed by the orphan enzyme α/ß hydrolase domain-containing protein 2 (ABHD2). We show that ABHD2 is highly expressed in spermatozoa, binds progesterone, and acts as a progesterone-dependent lipid hydrolase by depleting the endocannabinoid 2-arachidonoylglycerol (2AG) from plasma membrane. The 2AG inhibits the sperm calcium channel (CatSper), and its removal leads to calcium influx via CatSper and ensures sperm activation. This study reveals that progesterone-activated endocannabinoid depletion by ABHD2 is a general mechanism by which progesterone exerts its genome-independent action and primes sperm for fertilization.


Assuntos
Ácidos Araquidônicos/deficiência , Endocanabinoides/deficiência , Glicerídeos/deficiência , Hidrolases/metabolismo , Progesterona/metabolismo , Receptores de Progesterona/metabolismo , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Adulto , Animais , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Membrana Celular/metabolismo , Fertilização , Humanos , Hidrolases/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Progesterona/farmacologia , Ratos , Ratos Wistar , Receptores de Progesterona/genética , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Adulto Jovem
16.
Int J Public Health ; 61(3): 347-56, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26755457

RESUMO

OBJECTIVES: To estimate prevalence of diabetes mellitus (DM), success in diagnosing, and methods of diabetes management in China. METHODS: China Health and Retirement Longitudinal Study, a representative survey of the Chinese population at least 45 years old, is used to estimate diabetes and prediabetes prevalence, diagnosis, and treatment and their associations with residence, socioe-conomic, and demographic factors. RESULTS: Almost 60 % of middle-aged and elderly Chinese have prediabetes or diabetes in 2011-2012. DM prevalence increases with age, but the oldest group is least likely to be diagnosed. Prevalence is higher with higher body mass index, fasting cholesterol, and larger waist circumference. Higher prevalence is found in urban areas among residents with urban registration status (the Chinese administrative registration system or hukou), especially in coastal regions. Better rates of diagnosis, management, and education regarding diabetes are strongly associated with urban hukou, living in coastal areas, and in families with higher per capita expenditures, the appropriate economic resources measure in China. CONCLUSIONS: Diagnosis and management of diabetes is highly differential within China but recent efforts to improve health systems are succeeding in reducing undiagnosed disease. Current high prevalence of prediabetes suggests a more intensive effort is required in the future.


Assuntos
Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Hipoglicemiantes/uso terapêutico , Medicina Tradicional Chinesa , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , China/epidemiologia , Colesterol/sangue , Diabetes Mellitus/diagnóstico , Feminino , Humanos , Hipoglicemiantes/administração & dosagem , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , Características de Residência , Fatores de Risco , Fatores Socioeconômicos , Circunferência da Cintura
17.
PLoS One ; 10(9): e0137213, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26368323

RESUMO

Carotenoids are organic pigments that are produced predominantly by photosynthetic organisms and provide antioxidant activity to a wide variety of plants, animals, bacteria, and fungi. The carotenoid biosynthetic pathway is highly conserved in plants and occurs mostly in chromoplasts and chloroplasts. Leaf carotenoids play important photoprotective roles and targeted selection for leaf carotenoids may offer avenues to improve abiotic stress tolerance. A collection of 332 soybean [Glycine max (L.) Merr.] genotypes was grown in two years and total leaf carotenoid content was determined using three different methods. The first method was based on extraction and spectrophotometric determination of carotenoid content (eCaro) in leaf tissue, whereas the other two methods were derived from high-throughput canopy spectral reflectance measurements using wavelet transformed reflectance spectra (tCaro) and a spectral reflectance index (iCaro). An association mapping approach was employed using 31,253 single nucleotide polymorphisms (SNPs) to identify SNPs associated with total carotenoid content using a mixed linear model based on data from two growing seasons. A total of 28 SNPs showed a significant association with total carotenoid content in at least one of the three approaches. These 28 SNPs likely tagged 14 putative loci for carotenoid content. Six putative loci were identified using eCaro, five loci with tCaro, and nine loci with iCaro. Three of these putative loci were detected by all three carotenoid determination methods. All but four putative loci were located near a known carotenoid-related gene. These results showed that carotenoid markers can be identified in soybean using extract-based as well as by high-throughput canopy spectral reflectance-based approaches, demonstrating the utility of field-based canopy spectral reflectance phenotypes for association mapping.


Assuntos
Carotenoides , Genótipo , Glycine max , Extratos Vegetais/química , Folhas de Planta , Polimorfismo de Nucleotídeo Único , Carotenoides/biossíntese , Carotenoides/química , Carotenoides/genética , Loci Gênicos , Folhas de Planta/química , Folhas de Planta/genética , Folhas de Planta/metabolismo , Glycine max/química , Glycine max/genética , Glycine max/metabolismo
18.
Stem Cells Transl Med ; 4(3): 217-23, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25650438

RESUMO

There is a need for physical standards (reference materials) to ensure both reproducibility and consistency in the production of somatic cell types from human pluripotent stem cell (hPSC) sources. We have outlined the need for reference materials (RMs) in relation to the unique properties and concerns surrounding hPSC-derived products and suggest in-house approaches to RM generation relevant to basic research, drug screening, and therapeutic applications. hPSCs have an unparalleled potential as a source of somatic cells for drug screening, disease modeling, and therapeutic application. Undefined variation and product variability after differentiation to the lineage or cell type of interest impede efficient translation and can obscure the evaluation of clinical safety and efficacy. Moreover, in the absence of a consistent population, data generated from in vitro studies could be unreliable and irreproducible. Efforts to devise approaches and tools that facilitate improved consistency of hPSC-derived products, both as development tools and therapeutic products, will aid translation. Standards exist in both written and physical form; however, because many unknown factors persist in the field, premature written standards could inhibit rather than promote innovation and translation. We focused on the derivation of physical standard RMs. We outline the need for RMs and assess the approaches to in-house RM generation for hPSC-derived products, a critical tool for the analysis and control of product variation that can be applied by researchers and developers. We then explore potential routes for the generation of RMs, including both cellular and noncellular materials and novel methods that might provide valuable tools to measure and account for variation. Multiparametric techniques to identify "signatures" for therapeutically relevant cell types, such as neurons and cardiomyocytes that can be derived from hPSCs, would be of significant utility, although physical RMs will be required for clinical purposes.


Assuntos
Pesquisa Biomédica , Avaliação Pré-Clínica de Medicamentos , Células-Tronco Pluripotentes , Pesquisa Biomédica/instrumentação , Pesquisa Biomédica/métodos , Pesquisa Biomédica/normas , Pesquisa Biomédica/tendências , Avaliação Pré-Clínica de Medicamentos/economia , Avaliação Pré-Clínica de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/normas , Avaliação Pré-Clínica de Medicamentos/tendências , Humanos , Padrões de Referência
19.
J Acquir Immune Defic Syndr ; 68(1): 1-5, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25321184

RESUMO

Preclinical HIV prevention models use either a single high-dose viral challenge in depot medroxyprogesterone acetate-treated macaques or repeated viral challenges in cycling macaques. We tested the efficacy of an intravaginal tenofovir disoproxil fumarate (TDF) ring in a model combining repeated 30-mg injections of depot medroxyprogesterone acetate every 6 weeks with vaginal viral challenges weekly for 12 weeks. Twelve macaques were randomized to TDF or placebo rings. All placebo macaques became infected after a median of 2 exposures, whereas only 1 TDF macaque became infected at the eighth exposure (P = 0.0012). The TDF ring provides durable protection in a stringent challenge model.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , Acetato de Medroxiprogesterona/administração & dosagem , Ácidos Fosforosos/uso terapêutico , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vagina , Adenina/administração & dosagem , Adenina/uso terapêutico , Animais , Fármacos Anti-HIV/administração & dosagem , Preparações de Ação Retardada , Feminino , Infecções por HIV/transmissão , Macaca nemestrina , Ácidos Fosforosos/administração & dosagem , Placebos , Síndrome de Imunodeficiência Adquirida dos Símios/transmissão
20.
Health Policy Plan ; 30(6): 804-12, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25000963

RESUMO

The recent adoption of the World Health Assembly Resolution 66.12 for neglected tropical diseases (NTDs) in May 2013 is an important turning point for advocacy regarding a number of endemic zoonotic infections, defined by the World Health Organization as the neglected zoonotic diseases (NZDs). In addition to NTD-listed zoonoses such as rabies, echinococcosis (hydatid disease), leishmaniasis, Human African trypanosomiasis (sleeping sickness) and Taenia solium cysticercosis, the NZDs also include important bacterial zoonoses such as anthrax, bovine tuberculosis and brucellosis. To date, analysis of the processes that prioritize, develop and deliver zoonoses control programmes in many low- and middle-income countries is lacking, despite its potential to highlight significant evidence gaps and institutional constraints to the intersectoral approach required for their control. Policy process analysis was conducted via a series of semi-structured interviews with key policy actors within various ministries and institutes in Uganda and Nigeria. The study concluded that despite the rhetoric around 'linear' models of health policy development promoting consultation with a wide range of national stakeholders, the decision-making process for zoonotic disease control appears instead overtly influenced by the external political economy of trending pandemic threats, often overlooking national and regional zoonoses priorities. The inclusion of political systems remains a key factor in the zoonoses analysis matrix, enhancing our understanding of the intersectoral and transdisciplinary approaches required for their control. The authors consider policy process analysis to be a fundamental first step of any attempt to holistically strengthen human and animal health systems in a development context, particularly regarding the promotion of integrated control policies for regionally important zoonoses under the growing One Health movement.


Assuntos
Controle de Doenças Transmissíveis/organização & administração , Doenças Endêmicas/prevenção & controle , Política de Saúde , Zoonoses/prevenção & controle , Animais , Saúde Global , Humanos , Nigéria , Uganda
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