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BACKGROUND: Cardiovascular diseases (CVDs) are leading cause of death and primary cause of morbidity and mortality in diabetic population. Epicardial adipose tissue (EAT) covers the heart's surface and is a source of biomolecules regulating heart and blood vessel physiology. The protective activation of the unfolded protein response (UPR) and autophagy allows the cardiomyocyte reticular network to restore energy and/or nutrient homeostasis and to avoid cell death. However, an excessive or prolonged UPR activation can trigger cell death. UPR activation is an early event of diabetic cardiomyopathies and deregulated autophagy is associated with CVDs. RESULTS: An upregulation of UPR markers (glucose-regulated protein 78â¯KDa, glucose-regulated protein 94â¯KDa, inositol-requiring enzyme 1α, protein kinase RNA-like ER kinase and CCAAT/-enhancer-binding protein homologous protein (CHOP) gene) in EAT compared to subcutaneous adipose tissue (SAT), was observed as well as the UPR-related apoptosis marker caspase-4/procaspase-4 ratio but not in CHOP protein levels. Additionally, levels of ubiquitin and ubiquitinated proteins were decreased in EAT. Moreover, upregulation of autophagy markers (5' adenosine monophosphate-activated protein kinase, mechanistic target of rapamycin, Beclin 1, microtubule-associated protein light chain 3-II, lysosome-associated membrane protein 2, and PTEN-induced putative kinase 1) was observed, as well as an increase in the apoptotic Bim but not the ratio between Bim and the anti-apoptotic Bcl-2 in EAT. Diabetic patients show alterations in UPR activation markers but not in autophagy or apoptosis markers. CONCLUSION: UPR and autophagy are increased in EAT compared to SAT, opening doors to the identification of early biomarkers for cardiomyopathies and novel therapeutic targets.
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Diabetes Mellitus/metabolismo , Cardiomiopatias Diabéticas/patologia , Insuficiência Cardíaca/patologia , Pericárdio/metabolismo , Proteostase , Gordura Subcutânea/metabolismo , Idoso , Apoptose , Autofagia , Biomarcadores , Diabetes Mellitus/patologia , Cardiomiopatias Diabéticas/diagnóstico , Cardiomiopatias Diabéticas/metabolismo , Retículo Endoplasmático/patologia , Estresse do Retículo Endoplasmático , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/metabolismo , Humanos , Masculino , Miócitos Cardíacos/patologia , Pericárdio/citologia , Pericárdio/patologia , Gordura Subcutânea/citologia , Resposta a Proteínas não DobradasRESUMO
BACKGROUND: Health-related quality of life (HRQOL) in melanoma is affected by cancer stage. Previous studies have reported limited data on utility-based HRQOL. OBJECTIVES: To determine pooled estimates of utility-based HRQOL (utilities) for people with American Joint Cancer Committee stage I/II, III or IV melanoma for use in economic evaluations. METHODS: We performed a systematic review, meta-analysis and metaregression of utilities for patients with melanoma. HRQOL scores reported with the QLQ-C30, SF-36, SF-12, FACT-G and FACT-M instruments were converted to utilities using published mapping algorithms. Meta-analysis was used to calculate mean utilities. Metaregression was used to examine the effects of baseline patient and study characteristics. RESULTS: We identified 33 studies reporting 213 utilities. From meta-analyses, the mean utility for stage I/II melanoma was 0·97 [95% confidence interval (CI) 0·90-0·98]; for stage III melanoma it was 0·77 (95% CI 0·70-0·83); for stage III/IV 0·76 (95% CI 0·76-0·77); and for stage IV melanoma 0·76 (95% CI 0·71-0·81). The difference in utility between stage III and stage IV was not statistically significant (P = 0·52). For patients with stage I/II, the utility estimate at the time of surgery was 0·77 (95% CI 0·75-0·79), and at 3-12 months postsurgery it was 0·85 (95% CI 0·84-0·86). Utility estimates for patients with stage IV melanoma were 0·65 (95% CI 0·62-0·69) during the first 3 months of treatment and 0·83 (95% CI 0·81-0·86) at 4-12 months on treatment. For patients with stage IV melanoma treated with chemotherapy, the utility estimate was 0·52 (95% CI 0·51-0·52), while for those treated with targeted therapy it was 0·83 (95% CI 0·82-0·85). CONCLUSIONS: These robust, evidence-based estimates of health state utility can be used in economic evaluations of new treatments for patients with early-stage or advanced-stage melanoma.
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Melanoma/terapia , Qualidade de Vida , Neoplasias Cutâneas/terapia , Adulto , Antineoplásicos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cuidados Pós-Operatórios/estatística & dados numéricos , Anos de Vida Ajustados por Qualidade de VidaRESUMO
BACKGROUND: Receiving information about genomic risk of melanoma might trigger conversations about skin cancer prevention and skin examinations. OBJECTIVES: To explore conversations prompted by receiving personalized genomic risk of melanoma with family, friends and health professionals. METHODS: We used a mixed-methods approach. Participants without a personal history and unselected for a family history of melanoma (n = 103, aged 21-69 years, 53% women) completed questionnaires 3 months after receiving a personalized melanoma genomic risk assessment. Semistructured interviews were undertaken with 30 participants in high, average and low genomic risk categories, and data were analysed thematically. RESULTS: From the questionnaires, 74% of participants communicated their genomic risk information with family, and 49% with friends. Communication with a health professional differed by risk level: 41%, 16% and 12% for high, average and low risk, respectively (P = 0·01). Qualitative analysis showed that perceived 'shared risk' and perceived interest of family and friends were motivations for discussing risk or prevention behaviours. The information prompted conversations with family and health professionals about sun protection and skin checks, and general conversations about melanoma risk with friends. Reasons for not discussing with family included existing personal or family health concerns, or existing high levels of sun protection behaviour among family members. CONCLUSIONS: Personalized melanoma genomic risk information can prompt risk-appropriate discussions about skin cancer prevention and skin examinations with family and health professionals. Sharing this information with others might increase its impact on melanoma prevention and skin examination behaviours, and this process could be used to encourage healthy behaviour change within families.
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Melanoma/prevenção & controle , Exame Físico/psicologia , Autoexame/estatística & dados numéricos , Neoplasias Cutâneas/prevenção & controle , Pele , Adolescente , Adulto , Idoso , Comunicação , Tomada de Decisões , Relações Familiares , Estudos de Viabilidade , Feminino , Amigos , Genoma Humano , Humanos , Masculino , Melanoma/genética , Pessoa de Meia-Idade , New South Wales , Projetos Piloto , Relações Profissional-Paciente , Medição de Risco , Autorrevelação , Neoplasias Cutâneas/genética , Inquéritos e Questionários , Revelação da Verdade , Adulto JovemRESUMO
BACKGROUND: We hypothesised that alternating inhibitors of the vascular endothelial growth factor receptor (VEGFR) and mammalian target of rapamycin pathways would delay the development of resistance in advanced renal cell carcinoma (aRCC). PATIENTS AND METHODS: A single-arm, two-stage, multicentre, phase 2 trial to determine the activity, feasibility, and safety of 12-week cycles of sunitinib 50 mg daily 4 weeks on / 2 weeks off, alternating with everolimus 10 mg daily for 5 weeks on / 1 week off, until disease progression or prohibitive toxicity in favourable or intermediate-risk aRCC. The primary end point was proportion alive and progression-free at 6 months (PFS6m). The secondary end points were feasibility, tumour response, overall survival (OS), and adverse events (AEs). The correlative objective was to assess biomarkers and correlate with clinical outcome. RESULTS: We recruited 55 eligible participants from September 2010 to August 2012. DEMOGRAPHICS: mean age 61, 71% male, favourable risk 16%, intermediate risk 84%. Cycle 2 commenced within 14 weeks for 80% of participants; 64% received ≥22 weeks of alternating therapy; 78% received ≥22 weeks of any treatment. PFS6m was 29/55 (53%; 95% confidence interval [CI] 40% to 66%). Tumour response rate was 7/55 (13%; 95% CI 4% to 22%, all partial responses). After median follow-up of 20 months, 47 of 55 (86%) had progressed with a median progression-free survival of 8 months (95% CI 5-10), and 30 of 55 (55%) had died with a median OS of 17 months (95% CI 12-undefined). AEs were consistent with those expected for each single agent. No convincing prognostic biomarkers were identified. CONCLUSIONS: The EVERSUN regimen was feasible and safe, but its activity did not meet pre-specified values to warrant further research. This supports the current approach of continuing anti-VEGF therapy until progression or prohibitive toxicity before changing treatment. AUSTRALIAN NEW ZEALAND CLINICAL TRIALS REGISTRY: ACTRN12609000643279.
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Inibidores da Angiogênese/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma de Células Renais/tratamento farmacológico , Everolimo/administração & dosagem , Indóis/administração & dosagem , Neoplasias Renais/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Pirróis/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Austrália , Carcinoma de Células Renais/enzimologia , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Progressão da Doença , Intervalo Livre de Doença , Esquema de Medicação , Everolimo/efeitos adversos , Estudos de Viabilidade , Feminino , Humanos , Indóis/efeitos adversos , Neoplasias Renais/enzimologia , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Modelos de Riscos Proporcionais , Inibidores de Proteínas Quinases/efeitos adversos , Pirróis/efeitos adversos , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fatores de Risco , Sunitinibe , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: We sought to determine whether the substantial benefits of topical nitroglycerin with first-line, platinum-based, doublet chemotherapy in advanced nonsmall-cell lung cancer (NSCLC) seen in a phase II trial could be corroborated in a rigorous, multicenter, phase III trial. PATIENTS AND METHODS: Patients starting one of five, prespecified, platinum-based doublets as first-line chemotherapy for advanced NSCLC were randomly allocated treatment with or without nitroglycerin 25 mg patches for 2 days before, the day of, and 2 days after, each chemotherapy infusion. Progression-free survival (PFS) was the primary end point. RESULTS: Accrual was stopped after the first interim analysis of 270 events. Chemotherapy was predominantly with carboplatin and gemcitabine (79%) or carboplatin and paclitaxel (18%). The final analysis included 345 events in 372 participants with a median follow-up of 33 months. Topical nitroglycerin had no demonstrable effect on PFS [median 5.0 versus 4.8 months, hazard ratio (HR) = 1.07, 95% confidence interval (CI) 0.86-1.32, P = 0.55], overall survival (median 11.0 versus 10.3 months, HR = 0.99, 95% CI 0.79-1.24, P = 0.94), or objective tumor response (31% versus 30%, relative risk = 1.03, 95% CI 0.82-1.29, P = 0.81). Headache, hypotension, syncope, diarrhea, dizziness, and anorexia were more frequent in those allocated nitroglycerin. CONCLUSION: The addition of topical nitroglycerin to carboplatin-based, doublet chemotherapy in NSCLC had no demonstrable benefit and should not be used or pursued further. CLINICAL TRIALS NUMBER: Australian New Zealand Clinical Trials Registry Number ACTRN12608000588392.
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Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamento farmacológico , Nitroglicerina/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND/OBJECTIVES: The Sibutramine Cardiovascular OUTcomes (SCOUT) trial showed a significantly increased relative risk of nonfatal cardiovascular events, but not mortality, in overweight and obese subjects receiving long-term sibutramine treatment with diet and exercise. We examined the relationship between early changes (both increases and decreases) in pulse rate, and the impact of these changes on subsequent cardiovascular outcome events in both the placebo and sibutramine groups. SUBJECTS/METHODS: 9804 males and females, aged ⩾55 years, with a body mass index of 27-45 kg m(-)(2) were included in this current subanalysis of the SCOUT trial. Subjects were required to have a history of cardiovascular disease and/or type 2 diabetes mellitus with at least one cardiovascular risk factor, to assess cardiovascular outcomes. The primary outcome event (POE) was a composite of nonfatal myocardial infarction, nonfatal stroke, resuscitated cardiac arrest or cardiovascular death. Time-to-event analyses of the POE were performed using Cox regression models. RESULTS: During the initial 6-week sibutramine treatment period, the induced pulse rate increase was related to weight change (1.9±7.7 beats per minute (bpm) with weight increase; 1.4±7.3 bpm, 0-5 kg weight loss; 0.6±7.4 bpm, ⩾5 kg weight loss). Throughout the subsequent treatment period, those continuing on sibutramine showed a consistently higher mean pulse rate than the placebo group. There was no difference in POE rates with either an increase or decrease in pulse rate over the lead-in period, or during lead-in baseline to 12 months post randomization. There was also no relationship between pulse rate at lead-in baseline and subsequent cardiovascular events in subjects with or without a cardiac arrhythmia. CONCLUSION: Baseline pulse rate and changes in pulse rate may not be an important modifier nor a clinically useful predictor of outcome in an individual elderly cardiovascular obese subject exposed to weight management.
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Depressores do Apetite/administração & dosagem , Doenças Cardiovasculares/prevenção & controle , Ciclobutanos/administração & dosagem , Angiopatias Diabéticas/prevenção & controle , Frequência Cardíaca/efeitos dos fármacos , Obesidade/fisiopatologia , Idoso , Índice de Massa Corporal , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/epidemiologia , Angiopatias Diabéticas/tratamento farmacológico , Angiopatias Diabéticas/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/epidemiologia , Valor Preditivo dos Testes , Fatores de Risco , Resultado do Tratamento , Reino Unido/epidemiologia , Redução de PesoRESUMO
BACKGROUND/OBJECTIVES: The Sibutramine Cardiovascular OUTcomes (SCOUT) trial showed a significantly increased relative risk of nonfatal cardiovascular events, but not mortality, in overweight and obese subjects receiving long-term sibutramine treatment with diet and exercise. We examined the relationship between early changes (both increases and decreases) in body weight and blood pressure, and the impact of these changes on subsequent cardiovascular outcome events. SUBJECTS/METHODS: A total of 9804 male and female subjects, aged 55 years or older, with a body mass index of 27-45 kg m(-2) were included in this current subanalysis of the SCOUT trial. Subjects were required to have a history of cardiovascular disease and/or type 2 diabetes mellitus with at least one cardiovascular risk factor (hypertension, dyslipidemia, current smoking or diabetic nephropathy) to assess cardiovascular outcomes. Post hoc subgroup analyses of weight change (categories) and blood pressure were performed overall and by treatment group (6-week sibutramine followed by randomized placebo or continued sibutramine). The primary outcome event (POE) was a composite of nonfatal myocardial infarction, nonfatal stroke, resuscitated cardiac arrest or cardiovascular death. Time-to-event analyses of the POE were performed using Cox regression models with factors for treatment, subgroups and interactions. RESULTS: During the initial 6-week sibutramine treatment period, systolic blood pressure decreased progressively with increasing weight loss in hypertensive subjects (-8.1±10.5 mm Hg with <5 kg weight loss to -10.8±11.0 mm Hg with ⩾5 kg weight loss). The highest POE incidence occurred mainly in groups with increases in both weight and blood pressure. However, with long-term sibutramine treatment, a markedly lower blood pressure tended to increase POEs. CONCLUSION: Modest weight loss and modest lower blood pressure each reduced the incidence of cardiovascular events, as expected. However, the combination of early marked weight loss and rapid blood pressure reduction seems to be harmful in this obese elderly cardiovascular diseased population.
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Depressores do Apetite/uso terapêutico , Pressão Sanguínea , Doenças Cardiovasculares/complicações , Ciclobutanos/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/prevenção & controle , Obesidade/tratamento farmacológico , Redução de Peso , Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/prevenção & controle , Diabetes Mellitus Tipo 2/terapia , Angiopatias Diabéticas/fisiopatologia , Angiopatias Diabéticas/terapia , Método Duplo-Cego , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Obesidade/prevenção & controle , Sobrepeso/tratamento farmacológico , Estudos Prospectivos , Fatores de Risco , Comportamento de Redução do Risco , Resultado do TratamentoRESUMO
This paper discusses the structure, particle morphology, and optical properties of un-doped ZnO and ZnO doped with Er3+ and Yb3+ lanthanide ion nanoparticles (NPs) through a process denominated sol-gel-hydrothermal. According to the pattern of X-ray diffraction, ZnO:Er and ZnO:Yb is formed by a single-phase wurtzite structure with crystallites sized ~65 nm on average, and Er or Yb dopant ions in the hexagonal structure of ZnO, specifically in its distorted lattice sites. The results also suggest the possible role of oxygen vacancies or Ox- (defects) in the energy transfer from ZnO to the Er or Yb ions with a decrease of 3.18 eV and 3.19 eV in bandgap values to a red shift.
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BACKGROUND: For prospective meta-analyses (PMAs), eligible studies are identified, and the PMA hypotheses, selection criteria, and analysis methods are pre-specified before the results of any of the studies are known. This reduces publication bias and selective outcome reporting and provides a unique opportunity for outcome standardisation/harmonisation. We conducted a world-first PMA of four trials investigating interventions to prevent early childhood obesity. The aims of this study were to quantitatively analyse the effects of prospective planning on variations across trials, outcome harmonisation, and the power to detect intervention effects, and to derive recommendations for future PMA. METHODS: We examined intervention design, participant characteristics, and outcomes collected across the four trials included in the EPOCH PMA using their registration records, protocol publications, and variable lists. The outcomes that trials planned to collect prior to inclusion in the PMA were compared to the outcomes that trials collected after PMA inclusion. We analysed the proportion of matching outcome definitions across trials, the number of outcomes per trial, and how collaboration increased the statistical power to detect intervention effects. RESULTS: The included trials varied in intervention design and participants, this improved external validity and the ability to perform subgroup analyses for the meta-analysis. While individual trials had limited power to detect the main intervention effect (BMI z-score), synthesising data substantially increased statistical power. Prospective planning led to an increase in the number of collected outcome categories (e.g. weight, child's diet, sleep), and greater outcome harmonisation. Prior to PMA inclusion, only 18% of outcome categories were included in all trials. After PMA inclusion, this increased to 91% of outcome categories. However, while trials mostly collected the same outcome categories after PMA inclusion, some inconsistencies in how the outcomes were measured remained (such as measuring physical activity by hours of outside play versus using an activity monitor). CONCLUSION: Prospective planning led to greater outcome harmonisation and greater power to detect intervention effects, while maintaining acceptable variation in trial designs and populations, which improved external validity. Recommendations for future PMA include more detailed harmonisation of outcome measures and careful pre-specification of analyses to avoid research waste by unnecessary over-collection of data.
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Obesidade Infantil , Peso Corporal , Criança , Pré-Escolar , Dieta , Exercício Físico , Humanos , Obesidade Infantil/diagnóstico , Obesidade Infantil/prevenção & controle , Estudos ProspectivosRESUMO
The mechanisms of infection and dispersion of Trypanosoma cruzi among animals, especially in the sylvatic environment, are still not entirely clear, and various aspects of the transmission dynamics of this parasite in the sylvatic environment are still unknown. T. cruzi is a parasite with a great biological and genetic diversity that infects a wide variety of hosts, therefore, transmission cycles of this parasite are complex. The objective of this study was to determine the prevalence of T. cruzi infection and analyze the genetic variability of the discrete typing units (DTUs) of the parasite in three non-human primate species (Alouatta palliata, Alouatta pigra, and Ateles geoffroyi) in southeastern Mexico. A total of one hundred sixty-four serum samples (42 samples of A. pigra, 41 samples of A. palliata (free-ranging) and 81 samples of A. geoffroyi (hosted in care centers)) were analyzed for the detection of anti-T. cruzi antibodies by ELISA assays. The seroprevalence of infection was 23.39% in A. palliata, 21.40% in A. pigra and 16.27% in A. geoffroyi. Additionally, presence of parasite DNA was assessed by PCR, and the identification of DTUs was performed by real-time PCR coupled to High Resolution Melting (qPCR-HRM). Different DTUs (TcI, TcII, TcIII, TcV and TcVI) were found in the analyzed monkeys. In addition, infection of monkeys was not associated with age or gender, but it was associated with the species. This study reveals the risk of infection in the study area and that the different DTUs of the parasite can coexist in the same habitat, indicating that T. cruzi transmission in the study area is very complex and involves many ecological factors. However, there is a need for long-term studies of host-parasite interactions to provide a solid understanding of the ecology of these species and to understand the dispersion strategies of T. cruzi.
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Alouatta/parasitologia , Ateles geoffroyi/parasitologia , Doença de Chagas/transmissão , Doenças dos Macacos/transmissão , Trypanosoma cruzi/patogenicidade , Animais , Doença de Chagas/parasitologia , Doença de Chagas/veterinária , Genótipo , Interações Hospedeiro-Parasita , Humanos , México , Doenças dos Macacos/parasitologia , Estudos Soroepidemiológicos , Especificidade da Espécie , Trypanosoma cruzi/genéticaRESUMO
OBJECTIVE: Melanin-concentrating hormone (MCH) is a hypothalamic orexigenic neuropeptide that regulates energy balance. However, the distribution of MCH and its receptor MCHR1 in tissues other than brain suggested additional, as yet unappreciated, roles for this neuropeptide. Based on previous paradigms and the presence of MCH in the intestine as well as in immune cells, its potential role in gut innate immune responses was examined. METHODS: In human intestinal xenografts grown in mice, changes in the expression of MCH and its receptors following treatment with Clostridium difficile toxin A, the causative agent of antibiotic-associated diarrhoea in hospitalised patients, were examined. In colonocytes, the effect of C difficile toxin A treatment on MCHR1 expression, and of MCH on interleukin 8 (IL8) expression was examined. MCH-deficient mice and immunoneutralisation approaches were used to examine the role of MCH in the pathogenesis of C difficile toxin A-mediated acute enteritis. RESULTS: Upregulation of MCH and MCHR1 expression was found in the human intestinal xenograft model, and of MCHR1 in colonocytes following exposure to toxin A. Treatment of colonocytes with MCH resulted in IL8 transcriptional upregulation, implying a link between MCH and inflammatory pathways. In further support of this view, MCH-deficient mice developed attenuated toxin A-mediated intestinal inflammation and secretion, as did wild-type mice treated with an antibody against MCH or MCHR1. CONCLUSION: These findings signify MCH as a mediator of C difficile-associated enteritis and possibly of additional gut pathogens. MCH may mediate its proinflammatory effects at least in part by acting on epithelial cells in the intestine.
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Toxinas Bacterianas/toxicidade , Enterotoxinas/toxicidade , Hormônios Hipotalâmicos/fisiologia , Ileíte/microbiologia , Melaninas/fisiologia , Hormônios Hipofisários/fisiologia , Animais , Colo/metabolismo , Colo/transplante , Células Epiteliais/metabolismo , Humanos , Hormônios Hipotalâmicos/genética , Hormônios Hipotalâmicos/imunologia , Ileíte/metabolismo , Ileíte/patologia , Ileíte/prevenção & controle , Masculino , Melaninas/genética , Melaninas/imunologia , Camundongos , Camundongos Endogâmicos , Camundongos Knockout , Hormônios Hipofisários/genética , Hormônios Hipofisários/imunologia , RNA Mensageiro/genética , Receptores de Somatostatina/genética , Receptores de Somatostatina/imunologia , Receptores de Somatostatina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Transplante Heterólogo , Regulação para CimaRESUMO
We investigate the mechanisms of opening-mode fracture initiation in granular media. The study is based on a simulation of grain-scale fluid-grain interactions through a coupled numerical approach in which the discrete element method is used to solve for the mechanics of a solid granular medium, and computational fluid dynamics is used to model fluid flow and drag forces. We present benchmark problems with analytical solutions and validate this numerical model against experiments on a viscous-drag-driven cavity in the literature. Additional simulation results show fracture initiation mechanisms in a random granular packing subjected to constant boundary stresses and to fluid injection with a localized source. The dimensionless variable F_{s}/F_{sk} (ratio of seepage force F_{s} and skeletal force F_{sk}) incorporates the impacts of physical properties and injection parameters including fluid viscosity, injection velocity, grain size, and effective stresses, and it has been used as a criterion separating regimes of fluid invasion and drag-driven fracture opening. Our simulation results show that F_{s}/F_{sk} in combination with τ_{1} (ratio of diffusion time from hydromechanical coupling and injection time) serves as a prediction of fracture opening within granular packing. We suggest a simple criterion (F_{s}/F_{sk}>1 or τ_{1}>0.17) that is valid for various types of granular media and injection conditions to determine if fracture opening will occur. Among other applications, this study is useful to predict the initiation and propagation of fractures in natural sediments.
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Commercial aerosolized insecticides can be implemented as a community-based approach to targeted indoor residual spraying against Aedes aegypti, but their efficacy on pyrethroid-resistant mosquitoes has not yet been evaluated. Two commercial aerosolized products (H24 Poder Fulminante Ultra Eficaz®, carbamate, and Baygon Ultra Verde®, pyrethroid) were sprayed on common indoor surfaces e.g., cement, plywood, and cloth, and tested for their residual efficacy on susceptible and field-derived pyrethroid-resistant Ae. aegypti strains using the WHO cone bioassays. Overall, ≥80% 24-h mortality was observed for both products for at least 4 wk regardless of the mosquito strain or surface type used. H24 Poder Fulminante Ultra Eficaz showed the highest residual potency, sustaining >80% mortality for 7-wk posttreatment regardless of mosquito strain and surface type. For Baygon Ultra Verde, the mean mortality of female Ae. aegypti remained >80% for a shorter period (4-6 wk). Nonpyrethroid commercial aerosolized formulations can provide a lasting residual effect indoors compatible with the need for rapid and lasting mosquito control during outbreaks and may be suitable for community-based targeted indoor residual spraying.
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Aedes , Carbamatos , Inseticidas , Controle de Mosquitos , Piretrinas , Animais , Feminino , México , Resíduos de PraguicidasRESUMO
Y1.86Eu0.14WO6 phosphors were prepared using a solid-state reaction method. Their optical properties were analysed, and they was mixed with TiO2, sintered, and used as a photoelectrode (PE) in dye-sensitized solar cells (DSSCs). The as-prepared photoelectrode was characterized by photoluminescence spectroscopy, diffuse reflectance, electrochemical impedance spectroscopy (EIS) and X-ray diffraction. The photoelectric conversion efficiency of the DSSC with TiO2:Y1.86Eu0.14WO6 (100:2.5) was 25.8% higher than that of a DSCC using pure TiO2 as PE. This high efficiency is due to the ability of the luminescent material to convert ultraviolet radiation from the sun to visible radiation, thus improving the solar light harvesting of the DSSC.
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Two proteases, denoted beta- and gamma-secretase, process the beta-amyloid peptide precursor (APP) to yield the Abeta peptides involved in Alzheimer's disease. A third protein, alpha-secretase, cleaves APP near the middle of the Abeta sequence and thus prevents Abeta formation. These enzymes have defied identification. Because of its similarity to the systems of mammalian cells the yeast secretory system has provided important clues for finding mammalian processing enzymes. When expressed in Saccharomyces cerevisiae APP is processed by enzymes that possess the specificity of the alpha-secretases of multicellular organisms. APP processing by alpha-secretases occurred in sec1 and sec7 mutants, in which transport to the cell surface or to the vacuole is blocked, but not in sec17 or sec18 mutants, in which transport from the endoplasmic reticulum to the Golgi is blocked. Neutralization of the vacuole by NH4Cl did not block alpha-secretase action. The time course of processing of a pro-alpha-factor leader-APP chimera showed that processing by Kex2 protease, a Golgi protease that removes the leader, preceded processing by alpha-secretase. Deletions of the genes encoding the GPI-linked aspartyl proteases Yap3 and Mkc7 decreased alpha-secretase activity by 56 and 29%, respectively; whereas, the double deletion decreased the activity by 86%. An altered form of APP-695, in which glutamine replaced Lys-612 at the cleavage site, is cleaved by Yap3 at 5% the rate of the wild-type APP. Mkc7 protease cleaved APP (K612Q) at about 20% the rate of wild-type APP. The simplest interpretation of these results is that Yap3 and Mkc7 proteases are alpha-secretases which act on APP in the late Golgi. They suggest that GPI-linked aspartyl proteases should be investigated as candidate secretases in mammalian tissues.
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Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Pró-Proteína Convertases , Processamento de Proteína Pós-Traducional , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/enzimologia , Sequência de Aminoácidos , Cloreto de Amônio/farmacologia , Secretases da Proteína Precursora do Amiloide , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Clonagem Molecular , Endopeptidases/metabolismo , Proteínas Fúngicas/metabolismo , Glicosídeo Hidrolases/metabolismo , Glicosilação , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida/genética , Pepstatinas/farmacologia , Plasmídeos/genética , Subtilisinas/metabolismo , Temperatura , Transformação Genética/genética , Tunicamicina/farmacologia , beta-FrutofuranosidaseRESUMO
The purpose of this analysis of data from a larger investigation was to assess effects of anthropometric factors on free throw shooting performance of 15 girls from Michigan and 18 from Puerto Rico. Subjects performed 60 free throws (10 trials x 3 ball sizes x 2 basket heights). Correlations were low, with two exceptions, .53 between shooting performance at the low basket and grip strength (as measured by hand grip dynamometer) for girls from Michigan, and .49 for hand width and performance at the low basket for girls from Michigan.
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Basquetebol , Destreza Motora , Antropometria , Criança , Feminino , Força da Mão/fisiologia , HumanosRESUMO
Cyclosporin A (CsA) and sirolimus (SRL) are immunosuppressive agents (IAs) associated with dyslipidemia, insulin resistance and new onset diabetes after transplantation (NODAT). However, the molecular mechanisms involved are not fully understood. We investigated the effects of six-week treatment of either CsA or SRL on glucose and lipid metabolism in Wistar rats. The results show that, compared with vehicle-treated rats, SRL-treated rats were significantly lighter starting at week 5. CsA or SRL caused glucose intolerance, increased storage of lipids in the liver and skeletal muscle, and decreased the insulin-stimulated glucose uptake in isolated adipocytes. Furthermore, these agents significantly decreased genes involved in insulin action and glucose uptake, such as, IRS-1, Glut4 and Glut1, and increased genes and/or proteins involved in hepatic lipogenesis and gluconeogenesis, while decreasing them in adipose tissue. After either treatment PGC1α gene expression was down regulated in skeletal muscle, an important player in fatty acid oxidation. Moreover, there was an increase in IL-6 gene expression in adipose tissue in the SRL-treated rats, suggesting stimulation of lipolysis. The results of the present study suggest that CsA and SRL lead to metabolic alterations in liver, muscle and adipose tissue, which may contribute to the development of dyslipidemia and insulin resistance associated with immunosuppressive therapy.
Assuntos
Tecido Adiposo/metabolismo , Ciclosporina/metabolismo , Glucose/metabolismo , Metabolismo dos Lipídeos/fisiologia , Músculo Esquelético/metabolismo , Sirolimo/metabolismo , Tecido Adiposo/efeitos dos fármacos , Animais , Ciclosporina/farmacologia , Imunossupressores/metabolismo , Imunossupressores/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Músculo Esquelético/efeitos dos fármacos , Ratos , Ratos Wistar , Sirolimo/farmacologiaRESUMO
Brain tissue is highly dynamic in terms of electrical activity and energy demand. Relevant energy metabolites have turnover times ranging from milliseconds to seconds and are rapidly exchanged between cells and within cells. Until recently these fast metabolic events were inaccessible, because standard isotopic techniques require use of populations of cells and/or involve integration times of tens of minutes. Thanks to fluorescent probes and recently available genetically-encoded optical nanosensors, this Technology Report shows how it is now possible to monitor the concentration of metabolites in real-time and in single cells. In combination with ad hoc inhibitor-stop protocols, these probes have revealed a key role for K(+) in the acute stimulation of astrocytic glycolysis by synaptic activity. They have also permitted detection of the Warburg effect in single cancer cells. Genetically-encoded nanosensors currently exist for glucose, lactate, NADH and ATP, and it is envisaged that other metabolite nanosensors will soon be available. These optical tools together with improved expression systems and in vivo imaging, herald an exciting era of single-cell metabolic analysis.
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Introducción: La enfermedad granulomatosa crónica (EGC) es una forma infrecuente de inmunodeficiencia primaria que se caracteriza por una sensibilidad anormal a infecciones bacterianas y fúngicas, debida a un déficit en el complejo nicotinamida adenina dinucleótida fosfato oxidasa (NADPH) en los fagocitos. Objetivo: Describir tres casos de EGC con énfasis en su forma de presentación y realizar una revisión del tema. Casos Clínicos: Se presentan tres casos clínicos, dos de ellos con relación de parentesco (primos en primer grado). Se llegó a diagnóstico molecular en uno de los casos. Se destacan las manifestaciones clínicas: infecciones recurrentes, abscesos, adenitis y granulomas, y complicaciones, con la finalidad de facilitar la sospecha diagnóstica de EGC, debido a la importancia del diagnóstico temprano y el consejo genético. Conclusiones: La EGC es un trastorno inmunológico primario congénito infrecuente, con herencia ligada a X en su mayoría, pero también con formas autosómicas recesivas, con una forma de presentación característica y cuyo diagnóstico debe ser oportuno para evitar complicaciones, realizar profilaxis y tratamiento agresivo de las infecciones y consejo genético.
Introduction: Chronic granulomatous disease (CGD) is a rare form of primary immunodeficiency disease, characterized by an abnormal susceptibility to bacterial and fungal infections, and it is caused by a deficit in the phagocyte nicotinamide adenine dinucleotide phosphate oxidase complex (NADPH), resulting in the inability to generate reactive oxygen species that destroy micro-organisms. The diagnosis is based on clinical characteristics and analysis of phagocytes, and later confirmed by molecular studies. Its management should consider antimicrobial prophylaxis, a search for infections and aggressive management of these. Objective: To describe three cases of CGD emphasizing their forms of presentation and to conduct a review of the condition. Case reports: Three case reports, two of them first cousins, are presented. Molecular diagnosis was reached in one of the cases. Recurrent infections, abscesses, adenitis, granulomas and complications are identified to facilitate the suspected diagnosis of CGD, bearing in mind the importance of early diagnosis and genetic counseling. Conclusions: EGC is a rare congenital primary immunodeficiency disorder, mostly with X-linked inheritance, autosomal recessive form, and a specific presentation form. Its diagnosis should be timely to avoid complications. Prophylaxis and aggressive treatment of infections should be performed, as well as genetic counseling.