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We conducted a comparative cross-sectional study to compare the prevalence of exposure to workplace violence and intimate partner violence (IPV) in 125 female sex workers (FSWs) and 125 age-matched control women working in other professions (non-FSWs) and their children in El Alto, Bolivia. Violence exposure was assessed using the Demographic Health Survey Domestic Violence Module. To determine associations between work type and violence exposure, we conducted multivariate logistic regression. One-third of working mothers experienced sexual IPV, regardless of their profession. FSWs experienced higher rates of severe physical IPV and workplace violence. Children of FSWs were approximately three times more likely to be exposed to violence in the workplace. In Bolivia, strategies to reduce exposure to violence within the home and in FSW workplaces are paramount to minimizing negative impacts on women and their children. These findings have implications for policies to improve education, living wages, and social interventions to prevent and mitigate violence against women and children.
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Violencia Doméstica , Exposición a la Violencia , Violencia de Pareja , Trabajadores Sexuales , Humanos , Femenino , Niño , Estudios Transversales , Trabajo Sexual , Bolivia/epidemiología , Prevalencia , Parejas Sexuales , Factores de RiesgoRESUMEN
PURPOSE: Despite significant improvement in therapeutic development in the past decades, breast cancer remains a formidable cause of death for women worldwide. The hormone positive subtype (HR(+)) (also known as luminal type) is the most prevalant category of breast cancer, comprising ~70% of patients. The clinical success of the three CDK4/6 inhibitors palbociclib, ribociclib, and abemaciclib has revolutionized the treatment of choice for metastatic HR(+) breast cancer. Accumulating evidence demonstrate that the properties of CDK4/6 inhibitors extend beyond inhibition of the cell cycle, including modulation of immune function, sensitizing PI3K inhibitors, metabolism reprogramming, kinome rewiring, modulation of the proteosome, and many others. The ubiquitin-proteasome pathway (UPP) is a crucial cellular proteolytic system that maintains the homeostasis and turnover of proteins. METHODS: We performed transcriptional profiling of the HR(+) breast cancer cell lines MCF7 and T47D treated with Palbociclib. Differential expressed genes were analyzed for novel pathways enriched. The results were further validated with biochemical assays and with real world clinical database cohorts. RESULTS: We uncovered a novel mechanism that demonstrate the CDK4/6 inhibitors suppress the expression of three ubiquitin conjugating enzymes UBE2C, UBE2S, UBE2T. Further validation in the HR(+) cell lines show that Palbociclib and ribociclib decrease UBE2C at both the mRNA and protein level, but this phenomenon was not shared with abemaciclib. These three E2 enzymes modulate several E3 ubiquitin ligases, including the APC/C complex which plays a role in G1/S progression. We further demonstrate the UBE2C/UBE2T expression levels are associated with breast cancer survival, and HR(+) breast cancer cells demonstrate dependence on the UBE2C. CONCLUSIONS: Our study suggests a novel link between CDK4/6 inhibitor and UPP pathway, adding to the potential mechanisms of their clinical efficacy in cancer.
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Neoplasias de la Mama , Aminopiridinas , Bencimidazoles , Neoplasias de la Mama/patología , Quinasa 4 Dependiente de la Ciclina , Quinasa 6 Dependiente de la Ciclina , Femenino , Hormonas/uso terapéutico , Humanos , Fosfatidilinositol 3-Quinasas , Complejo de la Endopetidasa Proteasomal/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Purinas , ARN Mensajero , Enzimas Ubiquitina-Conjugadoras/genética , Enzimas Ubiquitina-Conjugadoras/metabolismo , Ubiquitinas/uso terapéuticoRESUMEN
Declines in physiological functions are the predominant risk factors for age-related diseases, such as cancers and neurodegenerative diseases. Therefore, delaying the aging process is believed to be beneficial in preventing the onset of age-related diseases. Previous studies have demonstrated that Graptopetalum paraguayense (GP) extract inhibits liver cancer cell growth and reduces the pathological phenotypes of Alzheimer's disease (AD) in patient IPS-derived neurons. Here, we show that GP extract suppresses ß-amyloid pathology in SH-SYS5Y-APP695 cells and APP/PS1 mice. Moreover, AMP-activated protein kinase (AMPK) activity is enhanced by GP extract in U87 cells and APP/PS1 mice. Intriguingly, GP extract enhances autophagy in SH-SYS5Y-APP695 cells, U87 cells, and the nematode Caenorhabditis elegans, suggesting a conserved molecular mechanism by which GP extract might regulate autophagy. In agreement with its role as an autophagy activator, GP extract markedly diminishes mobility decline in polyglutamine Q35 mutants and aged wild-type N2 animals in C. elegans. Furthermore, GP extract significantly extends lifespan in C. elegans.
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Envejecimiento/efectos de los fármacos , Crassulaceae/química , Extractos Vegetales/farmacología , Proteínas Quinasas Activadas por AMP/efectos de los fármacos , Péptidos beta-Amiloides/efectos de los fármacos , Animales , Autofagia/efectos de los fármacos , Caenorhabditis elegans/efectos de los fármacos , Técnicas de Cultivo de Célula , Modelos Animales de Enfermedad , Humanos , Longevidad/efectos de los fármacos , Ratones , Ratones TransgénicosRESUMEN
Alzheimer's disease (AD) is the most common type of dementia and also one of the leading causes of death worldwide. However, the underlying mechanisms remain unclear, and currently there is no drug treatment that can prevent or cure AD. Here, we have applied the advantages of using induced pluripotent stem cell (iPSC)-derived neurons (iNs) from AD patients, which are able to offer human-specific drug responsiveness, in order to evaluate therapeutic candidates for AD. Using approach involving an inducible neurogenin-2 transgene, we have established a robust and reproducible protocol for differentiating human iPSCs into glutamatergic neurons. The AD-iN cultures that result have mature phenotypic and physiological properties, together with AD-like biochemical features that include extracellular ß-amyloid (Aß) accumulation and Tau protein phosphorylation. By screening using a gene set enrichment analysis (GSEA) approach, Graptopetalum paraguayense (GP) has been identified as a potential therapeutic agent for AD from among a range of Chinese herbal medicines. We found that administration of a GP extract caused a significantly reduction in the AD-associated phenotypes of the iNs, including decreased levels of extracellular Aß40 and Aß42, as well as reduced Tau protein phosphorylation at positions Ser214 and Ser396. Additionally, the effect of GP was more prominent in AD-iNs compared to non-diseased controls. These findings provide valuable information that suggests moving extracts of GP toward drug development, either for treating AD or as a health supplement to prevent AD. Furthermore, our human iN-based platform promises to be a useful strategy when it is used for AD drug discovery.
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Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/genética , Crassulaceae/química , Fragmentos de Péptidos/genética , Proteínas tau/genética , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Diferenciación Celular/efectos de los fármacos , Descubrimiento de Drogas , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/metabolismo , Proteínas del Tejido Nervioso/genética , Neuronas/efectos de los fármacos , Neuronas/patologíaRESUMEN
BACKGROUND AND AIMS: Liver fibrosis is the excessive accumulation of extracellular matrix proteins, including collagen, which occurs in most types of chronic liver diseases. Advanced liver fibrosis results in cirrhosis, liver failure, and portal hypertension. Activated hepatic perivascular stellate cells, portal fibroblasts, and myofibroblasts of bone marrow origin have been identified as major collagen-producing cells in the injured liver. These cells are activated by fibrogenic cytokines, such as TGF-ß1. The inhibition of TGF-ß1 function or synthesis is a major target for the development of antifibrotic therapies. Our previous study showed that the water and ethanol extracts of Graptopetalum paraguayense (GP), a Chinese herbal medicine, can prevent dimethylnitrosamine (DMN)-induced hepatic inflammation and fibrosis in rats. METHODS: We used rat hepatic stellate HSC-T6 cells and a diethylnitrosamine (DEN)-induced rat liver injury model to test the potential mechanism of GP extracts and its fraction, HH-F3. RESULTS: We demonstrated that GP extracts and HH-F3 downregulated the expression levels of extracellular matrix (ECM) proteins and inhibited the proliferation and migration via suppression of the TGF-ß1 pathway in rat hepatic stellate HSC-T6 cells. Moreover, the HH-F3 fraction decreased hepatic collagen content and reduced plasma AST, ALT, and γ-GT activities in a DEN-induced rat liver injury model, suggesting that GP/HH-F3 has hepatoprotective effects against DEN-induced liver fibrosis. CONCLUSION: These findings indicate that GP/HH-F3 may be a potential therapeutic agent for the treatment of liver fibrosis. The inhibition of TGF-ß-mediated fibrogenesis may be a central mechanism by which GP/HH-F3 protects the liver from injury.
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Crassulaceae/química , Cirrosis Hepática/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Factor de Crecimiento Transformador beta/metabolismo , Animales , Línea Celular , Colágeno/genética , Colágeno/metabolismo , Proteínas de la Matriz Extracelular/genética , Proteínas de la Matriz Extracelular/metabolismo , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Humanos , Cirrosis Hepática/metabolismo , Extractos Vegetales/farmacología , Ratas , Ratas Wistar , Transducción de Señal , Factor de Crecimiento Transformador beta/genéticaRESUMEN
Abstract Background: Homophobic harassment can compromise mental health of sexual minority youths. Objectives: This study examined the rates of persistent and multisite homophobic harassment and their associations with school difficulties during childhood and adolescence among gay and bisexual men in Taiwan. Methods: Participants were recruited through advertisements on the Facebook, Bulletin Board Systems, and the home pages of health promotion and counseling centers for the gay, lesbian, and bisexual community. The experiences of traditional and cyber harassment based on gender role nonconformity and sexual orientation of 500 gay or bisexual men were examined. The associations of multisite and persistent harassment victimization with school difficulties were evaluated. Results: A total of 239 (47.8%) and 131 (26.2%) participants experienced persistent and multisite harassment victimization, respectively. Harassment victimization was significantly associated with low satisfaction with academic performance in any stage of study. Moreover, the participants who were harassed in senior high schools were more likely to miss classes or be truant than those who were not harassed. The victims of multisite harassment at senior high schools were more likely to miss classes or be truant than those of school-only harassment. Discussion: Prevention and intervention programs are warranted to reduce homophobic harassment in sexual minority youths.
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ABSTRACT Purpose The percentage of parenchyma preserved plays a predominant role in predicting renal function after partial nephrectomy (PN). Currently there is no standard method to estimate preserved renal parenchyma. In this study we propose a formula of the percentage of resected and ischemic volume (PRAIV) determined by a geometric model and evaluate the relationships between renal functional change and PRAIV as well as other clinical parameters. Materials and Methods We identified 71 patients who underwent open PN between January 2004 and April 2014. Assuming the kidney to be an ellipsoid with bilaterally equal volume and tumor to be a sphere, we calculated PRAIV by integral calculus. Nadir estimated glomerular filtration rate (eGFR) between postoperative 3 and 12 months were recorded. The correlation between percent eGFR reduction, PRAIV, and other clinical parameters were examined. Results On univariate analysis, age (p=0.03), depth of tumor invasion (p=0.004), C index (p=0.003), RAIV (p=0.04), and PRAIV (p<0.001) were correlated with percent reduction of eGFR. However, only age (p=0.007) and PRAIV (p<0.001) were significantly correlated with percent reduction of eGFR on multivariate analysis. Depicting these values along the regression line, we found R2 was 0.194 and 0.073 for PRAIV and age, respectively. Conclusions PRAIV determined by a geometric model is a significant predictor of renal functional change after PN. Using PRAIV, we can estimate percent eGFR reduction preoperatively for better patient consultation and surgical planning.
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Humanos , Masculino , Femenino , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Renales/cirugía , Isquemia Fría/métodos , Riñón/fisiopatología , Riñón/irrigación sanguínea , Riñón/patología , Neoplasias Renales/cirugía , Nefrectomía/métodos , Tamaño de los Órganos , Periodo Posoperatorio , Pregnanodionas , Valores de Referencia , Carcinoma de Células Renales/fisiopatología , Factores Sexuales , Análisis Multivariante , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores de Edad , Carga Tumoral , Tasa de Filtración Glomerular , Neoplasias Renales/fisiopatología , Persona de Mediana Edad , Modelos TeóricosRESUMEN
PURPOSE: The percentage of parenchyma preserved plays a predominant role in predicting renal function after partial nephrectomy (PN). Currently there is no standard method to estimate preserved renal parenchyma. In this study we propose a formula of the percentage of resected and ischemic volume (PRAIV) determined by a geometric model and evaluate the relationships between renal functional change and PRAIV as well as other clinical parameters. MATERIALS AND METHODS: We identified 71 patients who underwent open PN between January 2004 and April 2014. Assuming the kidney to be an ellipsoid with bilaterally equal volume and tumor to be a sphere, we calculated PRAIV by integral calculus. Nadir estimated glomerular filtration rate (eGFR) between postoperative 3 and 12 months were recorded. The correlation between percent eGFR reduction, PRAIV, and other clinical parameters were examined. RESULTS: On univariate analysis, age (p=0.03), depth of tumor invasion (p=0.004), C index (p=0.003), RAIV (p=0.04), and PRAIV (p<0.001) were correlated with percent reduction of eGFR. However, only age (p=0.007) and PRAIV (p<0.001) were significantly correlated with percent reduction of eGFR on multivariate analysis. Depicting these values along the regression line, we found R2 was 0.194 and 0.073 for PRAIV and age, respectively. CONCLUSIONS: PRAIV determined by a geometric model is a significant predictor of renal functional change after PN. Using PRAIV, we can estimate percent eGFR reduction preoperatively for better patient consultation and surgical planning.
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Carcinoma de Células Renales/cirugía , Isquemia Fría/métodos , Neoplasias Renales/cirugía , Riñón/irrigación sanguínea , Riñón/patología , Riñón/fisiopatología , Nefrectomía/métodos , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Carcinoma de Células Renales/fisiopatología , Femenino , Tasa de Filtración Glomerular , Humanos , Neoplasias Renales/fisiopatología , Masculino , Persona de Mediana Edad , Modelos Teóricos , Análisis Multivariante , Tamaño de los Órganos , Periodo Posoperatorio , Pregnanodionas , Valores de Referencia , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores Sexuales , Carga TumoralRESUMEN
BACKGROUND: Hepatocellular carcinoma (HCC) is the fifth most common malignancy and the third most common cause of cancer-related death worldwide. Sorafenib is the only drug for patients with advanced-stage hepatocellular carcinoma (HCC) that has been shown to confer a survival benefit to patients with HCC; however, it has many side effects. Thus, alternate therapeutic strategies with improved safety and therapeutic efficacy for the management of HCC should be developed. METHODS AND FINDINGS: We demonstrate that an extract of Graptopetalum paraguayense (GP) down-regulated the expression levels of several onco-proteins, including AURKA, AURKB, and FLJ10540, in HCC cells. To isolate the active components in the GP extracts, we prepared extracts fractions and assessed their effects on the expression of onco-proteins in HCC cells. The fraction designated HH-F3 was enriched in active ingredients, exhibited cytotoxic effects, and suppressed the expression of the onco-proteins in HCC cells. The structure of the main active compound in HH-F3 was found to be similar to that of the proanthocyanidin compounds derived from Rhodiola rosea. In addition, a distinct new compound rich in 3, 4, 5-trihydroxy benzylic moieties was identified in the HH-F3 preparations. Mechanistic studies indicated that HH-F3 induced apoptosis in HCC cells by promoting the loss of mitochondrial membrane potential and the production of reactive oxygen species. HH-F3 also enhanced PTEN expression and decreased AKT phosphorylation at Ser473 in a concentration-dependent manner in HCC cells. Moreover combination of GP or HH-F3 and sorafenib synergistically inhibits the proliferation of Huh7 cells. The treatment of a rat model with diethylnitrosamine (DEN)-induced liver cancer with extracts of GP and HH-F3 decreased hepatic collagen contents and inhibited tumor growth. CONCLUSIONS: These results indicate that GP extracts and HH-F3 can protect the liver by suppressing tumor growth; consequently, these compounds could be considered for the treatment of HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Neoplasias Experimentales , Extractos Vegetales/farmacología , Plantas Medicinales/química , Saxifragaceae/química , Animales , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino , Proteínas de Neoplasias/biosíntesis , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Extractos Vegetales/química , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Bolivian sex workers were more likely than other employed women to report tuberculosis screening only if they reported HIV screening. Of all women with household tuberculosis exposure, <40% reported screening for themselves or their children. Coupling tuberculosis screening with sex workers' mandatory HIV screenings may be a cost-efficient disease-control strategy.
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Trabajadores Sexuales , Tuberculosis/diagnóstico , Bolivia , Niño , Femenino , Humanos , Servicios de Salud Materno-Infantil , Calidad de la Atención de SaludRESUMEN
BACKGROUND: Graptopetalum paraguayense (GP) is a folk herbal medicine with hepatoprotective effects that is used in Taiwan. The aim of this study was to evaluate the hepatoprotective and antifibrotic effects of GP on experimental hepatic fibrosis in both dimethylnitrosamine (DMN)- and carbon tetrachloride (CCl(4))-induced liver injury rats. METHODS: Hepatic fibrosis-induced rats were fed with the methanolic extract of GP (MGP) by oral administration every day. Immunohistochemistry, biochemical assays, and Western blot analysis were performed. The effects of MGP on the expression of fibrotic markers and cytokines in the primary cultured hepatic stellate cells (HSCs) and Kupffer cells, respectively, were evaluated. RESULTS: Oral administration of MGP significantly alleviated DMN- or CCl(4)-induced liver inflammation and fibrosis. High levels of alanine transaminase, aspartate transaminase, bilirubin, prothrombin activity and mortality rates also decreased in rats treated with MGP. There were significantly decreased hydroxyproline levels in therapeutic rats compared with those of the liver-damaged rats. Collagen I and alpha smooth muscle actin (α-SMA) expression were all reduced by incubation with MGP in primary cultured rat HSCs. Furthermore, MGP induced apoptotic cell death in activated HSCs. MGP also suppressed lipopolysaccharide-stimulated rat Kupffer cell activation by decreasing nitric oxide, tumor necrosis factor-α and interleukin-6 production, and increasing interleukin-10 expression. CONCLUSIONS: The results show that the administration of MGP attenuated toxin-induced hepatic damage and fibrosis in vivo and inhibited HSC and Kupffer cell activation in vitro, suggesting that MGP might be a promising complementary or alternative therapeutic agent for liver inflammation and fibrosis.
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Helechos/química , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Macrófagos del Hígado/efectos de los fármacos , Macrófagos del Hígado/metabolismo , Cirrosis Hepática/metabolismo , Extractos Vegetales/farmacología , Animales , Apoptosis/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Citocinas/biosíntesis , Dimetilnitrosamina/efectos adversos , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/farmacología , Inflamación/metabolismo , Inflamación/patología , Hígado/efectos de los fármacos , Hígado/patología , Cirrosis Hepática/sangre , Cirrosis Hepática/tratamiento farmacológico , Masculino , Tamaño de los Órganos/efectos de los fármacos , Extractos Vegetales/administración & dosificación , Ratas , Bazo/efectos de los fármacosRESUMEN
The incidence of cirrhosis is rising due to the widespread occurrence of chronic hepatitis, as well as the evident lack of an established therapy for hepatic fibrosis. In the search for hepatoprotective therapeutic agents, Graptopetalum paraguayense (GP) showed greater cytotoxicity toward hepatic stellate cells than other tested herbal medicines. Histopathological and biochemical analyses suggest that GP treatment significantly prevented DMN-induced hepatic inflammation and fibrosis in rats. Microarray profiling indicated that expression of most of metabolism- and cell growth and/or maintenance-related genes recovered to near normal levels following GP treatment as classified by gene ontology and LSM analysis, was observed. ANOVA showed that expression of 64% of 256 liver damage-related genes recovered significantly after GP treatment. By examining rat liver samples with Q-RT-PCR, five liver damage-related genes were identified. Among them, Egr1 and Nrg1 may serve as necroinflammatory markers, and Btg2 may serve as a fibrosis marker. Oldr1 and Hmgcs1 were up- and down-regulated markers, respectively. A publicly accessible website has been established to provide access to these data Identification of 44 necroinflammation-related and 62 fibrosis-related genes provides useful insight into the molecular mechanisms underlying liver damage and provides potential targets for the rational development of therapeutic drugs such as GP.
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OBJECTIVE: Our goal was to describe current resident interest, participation, curricula, resources, and obstacles related to global health training within pediatric residency programs. METHODS: We conducted a cross-sectional survey of the 201 accredited pediatric residency programs in the United States, Puerto Rico, and the Caribbean from October 2006 to January 2007. Survey topics included resident interest and participation in electives, training opportunities, program support, and educational curricular content related to global health. RESULTS: Of the 201 surveyed pediatric residency programs, 106 (53%) responded. Fifteen percent of responding programs reported that a majority of their residents were interested in global health. Fifty-two percent offered a global health elective within the previous year, and 47% had formally incorporated global health into their training curricula. Six percent of the programs reported a formalized track or certificate in global health. The median number of residents per program participating in global health electives within the previous year was 0 during postgraduate year 1, 1 during postgraduate year 2, and 2 during postgraduate year 3. The median number of all residents per program participating in a global health elective in the previous year was 3 (7.4% of program size). Among programs that offered a global health elective, support to participating residents included prerequisite clinical training (36%), cultural orientation (36%), language training (15%), faculty mentorship (82%), and post-elective debriefing (77%). Fourteen percent of the programs provided full funding for resident electives. Characteristics of pediatric residency programs that were significantly associated with higher resident participation in a global health elective were larger program size, university affiliation, greater reported resident interest, and faculty involvement in global health. CONCLUSIONS: More than half of the pediatric residency programs surveyed offered a global health elective in the previous year. An American Academy of Pediatrics survey 10 years earlier had shown 1 of 4 programs with global health electives. Observance of American Academy of Pediatrics consensus guidelines for global health electives varied widely among programs, and additional efforts should focus on resident preparation, mentorship, and funding.
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Curriculum , Salud Global , Internado y Residencia , Pediatría/educación , Adulto , Estudios Transversales , Humanos , Internado y Residencia/organización & administración , Puerto Rico , Estados Unidos , Indias OccidentalesRESUMEN
Solid-phase microextraction coupled with gas chromatography-mass spectrometry (SPME-GC-MS) was used to analyze two triazine (atrazine and simazine) and three chloroacetamide herbicides (acetochlor, alachlor, and metolachlor) in water samples from a midwest US agricultural drainage ditch for two growing seasons. The effects of salt concentration, sample volume, extraction time, and injection time on extraction efficiency using a 100-mum polydimethylsiloxane-coated fiber were investigated. By optimizing these parameters, ditch water detection limits of 0.5 microgL(-1) simazine and 0.25 microgL(-1) atrazine, acetochlor, alachlor, and metolachlor were achieved. The optimum salt concentration was found to be 83% NaCl, while sample volume (10 or 20 mL) negligibly affected analyte peak areas. The optimum extraction time was 40 min, and the optimum injection time was 15 min. Results indicated that atrazine levels in the ditch water exceeded the US maximum contaminant level for drinking water 12% of the time, and atrazine was the most frequently detected among studied analytes.