Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
PLoS One ; 18(6): e0287627, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37384792

RESUMO

BACKGROUND: Adolescents in sub-Saharan Africa (SSA) remain vulnerable to HIV infection. While pre-exposure prophylaxis (PrEP) is highly effective in preventing HIV transmission as a daily or on-demand regimen, tailored approaches are necessary. The Combined HIV Adolescent PrEP and Prevention Study (CHAPS) is a mixed-methods research program investigating the acceptability and feasibility of implementing daily and on-demand PrEP among young people in SSA. It also aims to determine an on-demand dosing schedule for insertive sex. For this paper, we explored preferences for daily versus on-demand PrEP amongst adolescents as part of CHAPS. METHODS: Purposive sampling was used to recruit participants from Soweto and Cape Town (South Africa), Wakiso district (Uganda) and Chitungwiza (Zimbabwe). At the time of the study in 2018/2019, Uganda had not rolled out PrEP to the general population; in Zimbabwe, PrEP for young people was only available at selected sites with one located within the study recruitment area. In South Africa, PrEP was made available to selected high-risk groups. We conducted 60 in-depth interviews and 24 group discussions amongst young people aged 13-24 without HIV in South Africa, Uganda, and Zimbabwe. All in-depth interviews and group discussions were audio-recorded, transcribed verbatim and translated to English. Data were analysed using framework analysis. The main themes were centered around preferences for daily and on-demand PrEP. RESULTS: Reasons for on-demand preferences included stigma, pill fatigue, adherence and side effects. Reasons for daily PrEP preferences included factors related to sexual risk behaviour, continuous protection against incidents of unintentional exposure, and the increased efficacy of a daily dose. Participants at all sites preferring daily PrEP identified the same reasons, with more males than females citing inadvertent blood contact or perceived increased efficacy. Similarly, participants at all sites preferring on-demand PrEP gave the same reasons for their preferences for on-demand PrEP; the exception was South Africans who did not mention the hope of having fewer side effects by not taking daily PrEP. Additionally, more males than females cited intermittent sex as a reason for opting for on-demand PrEP. CONCLUSIONS: Our study is the first known to explore and describe youth preferences for daily versus on-demand PrEP. While the choice is clear-cut, the reasons cited in the different options provide invaluable insights into their decisions, and the actual and perceived facilitators and barriers to access to PrEP. Further education is needed amongst young people, not only about PrEP but also in other areas of comprehensive sexuality education. Exploring all options of HIV prevention is crucial to provide a tailored, one-size-does-not-fit-all approach to adolescent care in SSA to reduce and, the continued and increasing risk of this preventable infection.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Infecções por HIV , Profilaxia Pré-Exposição , Adolescente , Feminino , Masculino , Humanos , África do Sul , Uganda , Zimbábue , Infecções por HIV/prevenção & controle
2.
Sci Rep ; 10(1): 866, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964941

RESUMO

Proton pump inhibitors (PPIs) are used for the long-term treatment of gastroesophageal disorders and the non-prescription medicines for acid reflux. However, there is growing concerns about PPI misuse, overuse and abuse. This study aimed to develop an animal model to examine the effects of long-term use of PPI in vivo. Twenty one Wistar rats were given omeprazole orally or intravenously for 30 days, and caerulein as a positive control. After euthanization, the serum and stool were collected to perform MS-based quantitative analysis of metabolites. We carried out 16S-based profiling of fecal microbiota, assessed the expression of bile acid metabolism regulators and examined the immunopathological characteristics of bile ducts. After long-term PPI exposure, the fecal microbial profile was altered and showed similarity to those observed in high-fat diet studies. The concentrations of several metabolites were also changed in various specimens. Surprisingly, morphological changes were observed in the bile duct, including ductal epithelial proliferation, micropapillary growth of biliary epithelium, focal bile duct stricture formation and bile duct obstruction. These are characteristics of precancerous lesions of bile duct. FXR and RXRα expressions were significantly reduced, which were similar to that observed in cholangiocarcinoma in TCGA and Oncomine databases. We established a novel animal model to examine the effects of long-term use of omeprazole. The gut microbes and metabolic change are consequences of long-term PPI exposure. And the results showed the environment in vivo tends to a high-fat diet. More importantly, we observed biliary epithelial hyperplasia, which is an indicator of a high-fat diet.


Assuntos
Ductos Biliares/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Omeprazol/efeitos adversos , Inibidores da Bomba de Prótons/efeitos adversos , Administração Oral , Animais , Neoplasias dos Ductos Biliares/genética , Ductos Biliares/patologia , Transformação Celular Neoplásica/efeitos dos fármacos , Colangiocarcinoma/genética , Colestase/induzido quimicamente , Colestase/patologia , Fezes/microbiologia , Microbioma Gastrointestinal/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Omeprazol/administração & dosagem , Omeprazol/farmacologia , Inibidores da Bomba de Prótons/administração & dosagem , Inibidores da Bomba de Prótons/farmacologia , RNA Ribossômico 16S , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ratos Wistar , Receptor X Retinoide alfa/genética , Receptor X Retinoide alfa/metabolismo , Tirosina/sangue , alfa-Tocoferol/sangue
3.
Front Pharmacol ; 9: 778, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30087612

RESUMO

Lung cancer is one of the major cause of cancer-related deaths worldwide. The poor prognosis and resistance to both radiation and chemotherapy urged the development of potential targets for lung cancer treatment. In this study, using a network-based cellular signature bioinformatics approach, we repurposed a clinically approved mTOR inhibitor for renal cell carcinomans, temsirolimus, as the potential therapeutic candidate for lung adenocarcinoma. The PI3K-AKT-mTOR pathway is known as one of the most frequently dysregulated pathway in cancers, including non-small-cell lung cancer. By using a well-documented lung adenocarcinoma mouse model of human pathophysiology, we examined the effect of temsirolimus on the growth of lung adenocarcinoma in vitro and in vivo. In addition, temsirolimus combined with reduced doses of cisplatin and gemcitabine significantly inhibited the lung tumor growth in the lung adenocarcinoma mouse model compared with the temsirolimus alone or the conventional cisplatin-gemcitabine combination. Functional imaging techniques and microscopic analyses were used to reveal the response mechanisms. Extensive immunohistochemical analyses were used to demonstrate the apparent effects of combined treatments on tumor architecture, vasculature, apoptosis, and the mTOR-pathway. The present findings urge the further exploration of temsirolimus in combination with chemotherapy for treating lung adenocarcinoma.

4.
Biomed Microdevices ; 19(4): 84, 2017 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-28929244

RESUMO

Traditional drug delivery systems, using invasive, transdermal, and oral routes, are limited by various factors, such as the digestive system environment, skin protection, and sensory nerve stimulation. To improve the drug delivery system, we fabricated a polysaccharide-based, dissolvable microneedle-based array, which combines the advantages of both invasive and transdermal delivery systems, and promises to be an innovative solution for minimally invasive drug delivery. In this study, we designed a reusable aluminum mold that greatly improved the efficiency and convenience of microneedle fabrication. Physical characterization of the polysaccharides, individual or mixed at different ratios, was performed to identify a suitable molecule to fabricate the dissolvable microneedle. We used a vacuum deposition-based micro-molding method at low temperature to fabricate the model. Using a series of checkpoints from material into product, a systematic feedback mechanism was built into the "all-in-one" fabrication step, which helped to improve production yields. The physical properties of the fabricated microneedle were assessed. The cytotoxicity analysis and animal testing of the microneedle demonstrated the safety and compatibility of the microneedle, and the successful penetration and effective release of a model protein.


Assuntos
Plásticos Biodegradáveis , Teste de Materiais , Agulhas , Administração Cutânea , Animais , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células NIH 3T3
5.
PLoS One ; 12(4): e0175586, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28419107

RESUMO

Developing lung cancer in mouse models that display similarities of both phenotype and genotype will undoubtedly provide further and better insights into lung tumor biology. Moreover, a high degree of pathophysiological similarity between lung tumors from mouse models and their human counterparts will make it possible to use these mouse models for preclinical tests. Ovine pulmonary adenocarcinomas (OPAs) present the same symptoms as adenocarcinomas in humans and are caused by a betaretrovirus. OPAs have served as an exquisite model of carcinogenesis for human lung adenocarcinomas. In this study, we characterized the histopathology and transcriptome profiles of a jaagsiekte sheep retrovirus (JSRV)-envelope protein (Env) transgenic mouse model with spontaneous lung tumors, and associations of the transcriptome profiles with tumor invasion/metastasis, especially the phenomenon of the epithelial-mesenchymal transition (EMT). Genetic information obtained from an expression array was analyzed using an ingenuity pathways analysis (IPA) and human disease database (MalaCards). By careful examination, several novel EMT-related genes were identified from tumor cells using RT-qPCR, and these genes also scored high in MalaCards. We concluded that the JSRV-Env mouse model could serve as a spontaneous lung adenocarcinoma model with a metastatic phenotype, which will benefit the study of early-onset and progression of lung adenocarcinoma. In addition, it can also be a valuable tool for biomarkers and drug screening, which will be helpful in developing intervention therapies.


Assuntos
Adenocarcinoma/patologia , Modelos Animais de Doenças , Neoplasias Pulmonares/patologia , Pulmão/patologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Animais , Transição Epitelial-Mesenquimal/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Retrovirus Jaagsiekte de Ovinos/genética , Pulmão/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos Transgênicos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/análise , Metástase Neoplásica , Proteínas Nucleares/análise , Fenótipo , Adenomatose Pulmonar Ovina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ovinos , Fator Nuclear 1 de Tireoide , Fatores de Transcrição/análise , Proteínas do Envelope Viral/genética
6.
Int J Biochem Cell Biol ; 79: 231-238, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27592451

RESUMO

KLF10 is a transforming growth factor (TGF)-ß/Smad downstream regulated gene. KLF10 binds to the promoter of target genes and mimics the effects of TGF-ß as a transcriptional factor. In our laboratory, we noted that Klf10 deficiency in mice is associated with significant inflammation of the lungs. However, the precise mechanism of this association remains unknown. We previously identified NPRA as a target gene potentially regulated by KLF10 through direct binding; NPRA knockout have known that prevented lung inflammation in a mouse model of allergic asthma. Here, we further explored the regulatory association between KLF10 and NPRA on the basis of the aforementioned findings. Our results demonstrated that KLF10 acts as a transcriptional repressor of NPRA and that KLF10 binding reduces NPRA expression in vitro. Compared with wild-type mice, Klf10-deficient mice were more sensitive to lipopolysaccharide or ovalbumin challenge and showed more severe inflammatory histological changes in the lungs. Moreover, Klf10-deficient mice showed pulmonary neutrophil accumulation. These findings collectively reveal the precise site where KLF10 signaling affects pulmonary inflammation by attenuating NPRA expression. They also verify the importance of KLF10 and atrial natriuretic peptide/NPRA in exerting influences on chronic pulmonary disease pathogenesis.


Assuntos
Fatores de Transcrição de Resposta de Crescimento Precoce/deficiência , Regulação da Expressão Gênica , Fatores de Transcrição Kruppel-Like/deficiência , Pneumonia/genética , Pneumonia/metabolismo , Receptores do Fator Natriurético Atrial/genética , Receptores do Fator Natriurético Atrial/metabolismo , Animais , Permeabilidade Capilar , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/citologia , Pneumonia/imunologia , Regiões Promotoras Genéticas/genética , Transcrição Gênica
7.
Int J Biochem Cell Biol ; 60: 53-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25578559

RESUMO

TGF-ß plays a significant role in regulating pancreas islet function and maintaining their mass. KLF10, a TGF-ß downstream gene, belongs to a group of Krüppel-like transcription factors that bind to the promoters of target genes and produce effects that mimic TGF-ß as a tumor suppressor. Using ChIP-chip screening, SEI-1 was identified as a target gene that may be regulated by KLF10. We conducted a series of assays to verify the presence of unknown regulation events between SEI-1 and KLF10. These showed that KLF10 transcriptionally activates the SEI-1 promoter and, furthermore, induces SEI-1 protein expression in pancreatic carcinoma cells. SEI-1 is one of the key factors involved in cell cycle control through the regulation of other transcription factors such as the p21(Cip1) gene. Interestingly, it has been shown previously that p21(Cip1) is indirectly activated by KLF10. Our results first demonstrated that KLF10 acts as a transcriptional activator on SEI-1, which can then result in increased p21(Cip1) expression. Furthermore, KLF10-deficiency in mice is associated with a decrease in the pancreatic islet mass, which is similar to the effects found in SEI-1 deficient mice. The KLF10-defect was also associated with the nuclear accumulation of the p21(Cip1) in islet cells. Based on our molecular and histological findings, we conclude that KLF10 plays an important role in pancreatic ß-cells and this supports a functional link between KLF10 and various cell cycle regulators, most notably in the context of the pancreas.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Fatores de Transcrição de Resposta de Crescimento Precoce/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas Nucleares/metabolismo , Pâncreas/metabolismo , Transativadores/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/genética , Fatores de Transcrição de Resposta de Crescimento Precoce/genética , Ensaio de Desvio de Mobilidade Eletroforética , Teste de Tolerância a Glucose , Humanos , Imuno-Histoquímica , Fatores de Transcrição Kruppel-Like/genética , Camundongos , Proteínas Nucleares/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transativadores/genética , Fatores de Transcrição
8.
J Expo Anal Environ Epidemiol ; 14(7): 529-35, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15039796

RESUMO

In Taiwan 24-h coffee shops have become popular gathering areas for young people. This study assesses customers' exposures to PM(2.5) and gaseous/particulate polycyclic aromatic hydrocarbons (PAHs) in such an environment. Potential influential factors were also evaluated. Two coffee shops with different types of smoking/nonsmoking divisions were selected. Sampling was conducted from 1300 to 2100 hours on Saturdays and Sundays during December 2000 and January 2001. Personal environmental monitors mounted with Teflon filters and polyurethane foams were used for particulate and gaseous sampling. PAHs were analyzed with GC-FID. Principal component analysis was used to explore the differences in the patterns of gaseous and particulate PAHs. Stepwise regression analysis was used to evaluate the contribution of various factors. The geometric mean (GM) of PM(2.5), particulate and gaseous PAH exposures were 83.7, 0.46 and 1.01 microg/m(3), respectively. Their exposure concentrations were about two to five times those of residential indoor environments in Taiwan. Smoking and vehicle exhaust were two major exposure sources. The gaseous PAH concentrations in the two sections of both shops were significantly correlated. The divisions between smoking and nonsmoking sections in neither of the coffee shops were effective to prevent dispersion of gaseous pollutants. In both shops, the concentrations of PM(2.5) and associated PAHs, respectively, were about 22-28 microg/m(3) and 0.07 microg/m(3) higher in smoking areas compared to nonsmoking areas. It was also found that each additional cigarette resulted in a 0.22-0.42 microg/m(3) PM(2.5) incremental increase in nonsmoking customers' exposure in the smoking section.


Assuntos
Exposição Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Restaurantes , Poluição por Fumaça de Tabaco/análise , Movimentos do Ar , Cromatografia Gasosa , Monitoramento Ambiental , Humanos , Tamanho da Partícula , Taiwan
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...