Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Vaccine ; 41(2): 540-546, 2023 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-36496281

RESUMEN

This study examines the personal beliefs held by parents of autistic children in Puerto Rico regarding the cause of their child's autism and how these beliefs may influence parental vaccination decision-making. This study seeks to contribute towards diversifying the autism literature by focusing on an autism community living in a relatively lower income, resource-deficit context. These findings expand our understandings of how parents of autistic children may perceive vaccines and how these perceptions are informed by various sources of knowledge. This ethnographic research study was conducted between May 2017 and August 2019. Methods included 350+ hours of participant-observation and semi-structured interviewing of 35 Puerto Rican parents of autistic children. 32 of these 35 parents interviewed believed autism to be the result of genetic risks that are 'triggered' by an unknown environmental factor. Suggested 'triggers' included various environmental contaminants and vaccinations. The subject of vaccination came up in every interview; 18 interviewed parents did not believe vaccines 'triggered' autism, 3 parents attributed their child's autism entirely to vaccines, while 14 considered vaccines to be one of several possible 'triggers'. It is important to note that no parents interviewed perceived vaccinations to be inherently or universally harmful. Rather, they perceived vaccinations to be one of many possible 'triggers' for a child predisposed to develop autism. In some cases, this perception prompted parents to oppose mandatory vaccination policies on the island. Parents shared nuanced, complex understandings of autism causation that may carry implications for COVID-19 vaccine uptake within the Puerto Rican autistic community.


Asunto(s)
Trastorno Autístico , Padres , Vacilación a la Vacunación , Vacunas , Niño , Humanos , Trastorno Autístico/etiología , COVID-19 , Vacunas contra la COVID-19 , Conocimientos, Actitudes y Práctica en Salud , Puerto Rico , Vacunación/psicología , Vacunas/efectos adversos , Vacilación a la Vacunación/etnología , Vacilación a la Vacunación/psicología , Antropología Cultural , Antropología Médica
2.
Clin Cancer Res ; 13(18 Pt 1): 5305-13, 2007 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-17875759

RESUMEN

OBJECTIVES: The molecular factors contributing to the development of Barrett's esophagus (BE) are unclear. Our previous studies showed that BE tissues secrete interleukin-6 (IL-6) and express proteins associated with IL-6 signaling, including IL-6 receptor, activated signal transducer and activators of transcription 3 (STAT3), and antiapoptotic proteins Bcl-x(L) and Mcl-1. Here, we test the hypothesis that bile acids and gastric acids, two components of refluxate associated with gastresophageal reflux disease, activate the IL-6/STAT3 pathway. MATERIALS AND METHODS: Immunohistochemistry was used to assess levels of phosphorylated STAT3 in esophageal tissue samples from BE patients with different grades of dysplasia. Seg-1 esophageal adenocarcinoma cells were evaluated for STAT3 activation and IL-6 and Bcl-x(L) expression by molecular biology techniques, including Western blot, reverse transcription-PCR, and ELISA after exposure to control media (pH 7.4), media supplemented with a 0.1 mmol/L bile acid cocktail with media at pH 4 or media at pH 4 with bile acid cocktail. RESULTS: Immunohistochemical analysis showed that activated, phosphorylated STAT3 is expressed in nuclei of dysplastic BE and cancer tissues. Treatment of Seg-1 cells with media containing bile acid cocktail and acidified to pH 4 resulted in increased activation of STAT3, IL-6 secretion, and increased expression of Bcl-x(L). Inhibition of the STAT3 pathway using STAT3 small interfering RNA or Janus-activated kinase inhibitor resulted in increased apoptosis. CONCLUSIONS: The IL-6/STAT3 antiapoptotic pathway is induced by short exposure to bile acid cocktail and low pH. This alteration, if persistent in vivo, may underlie the development of dysplastic BE and tumor progression.


Asunto(s)
Esófago de Barrett/metabolismo , Ácidos y Sales Biliares/metabolismo , Esófago/metabolismo , Interleucina-6/metabolismo , Factor de Transcripción STAT3/metabolismo , Adenocarcinoma/química , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis , Esófago de Barrett/patología , Ácidos y Sales Biliares/farmacología , Neoplasias Esofágicas/química , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Esófago/efectos de los fármacos , Esófago/patología , Femenino , Ácido Gástrico/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Interleucina-6/genética , Masculino , Persona de Mediana Edad , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Factor de Transcripción STAT3/análisis , Factor de Transcripción STAT3/genética , Células Tumorales Cultivadas , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
3.
Gut ; 56(6): 763-71, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17145738

RESUMEN

BACKGROUND: Barrett's oesophagus is a premalignant condition associated with an increased risk for the development of oesophageal adenocarcinoma (ADCA). Previous studies indicated that oxidative damage contributes to the development of ADCA. OBJECTIVE: To test the hypothesis that bile acids and gastric acid, two components of refluxate, can induce oxidative stress and oxidative DNA damage. METHODS: Oxidative stress was evaluated by staining Barrett's oesophagus tissues with different degrees of dysplasia with 8-hydroxy-deoxyguanosine (8-OH-dG) antibody. The levels of 8-OH-dG were also evaluated ex vivo in Barrett's oesophagus tissues incubated for 10 min with control medium and medium acidified to pH 4 and supplemented with 0.5 mM bile acid cocktail. Furthermore, three oesophageal cell lines (Seg-1 cells, Barrett's oesophagus cells and HET-1A cells) were exposed to control media, media containing 0.1 mM bile acid cocktail, media acidified to pH 4, and media at pH 4 supplemented with 0.1 mM bile acid cocktail, and evaluated for induction of reactive oxygen species (ROS). RESULTS: Immunohistochemical analysis showed that 8-OH-dG is formed mainly in the epithelial cells in dysplastic Barrett's oesophagus. Importantly, incubation of Barrett's oesophagus tissues with the combination of bile acid cocktail and acid leads to increased formation of 8-OH-dG. An increase in ROS in oesophageal cells was detected after exposure to pH 4 and bile acid cocktail. CONCLUSIONS: Oxidative stress and oxidative DNA damage can be induced in oesophageal tissues and cells by short exposures to bile acids and low pH. These alterations may underlie the development of Barrett's oesophagus and tumour progression.


Asunto(s)
Esófago de Barrett/metabolismo , Ácidos y Sales Biliares/fisiología , Daño del ADN , Estrés Oxidativo , 8-Hidroxi-2'-Desoxicoguanosina , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis/efectos de los fármacos , Esófago de Barrett/genética , Esófago de Barrett/patología , Ácidos y Sales Biliares/farmacología , Biopsia , Medios de Cultivo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Progresión de la Enfermedad , Esófago/efectos de los fármacos , Esófago/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Microscopía Fluorescente , Persona de Mediana Edad , Estrés Oxidativo/efectos de los fármacos , Células Tumorales Cultivadas
4.
Am J Gastroenterol ; 100(2): 424-31, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15667503

RESUMEN

BACKGROUND AND AIMS: Barrett's esophagus (BE) is a premalignant lesion of the distal esophagus in which squamous epithelial cells are replaced by metaplastic intestinal-like columnar epithelium that contains goblet cells. The factors that contribute to the progression from normal squamous mucosa to BE, Barrett's dysplasia, and adenocarcinoma are not well understood at the molecular level. Since reflux of bile acids is associated with BE development, we speculate that cells with an apoptosis-resistant phenotype are selected after long-term repeated exposure to pulses of bile acids. This will result in the survival of cells with unrepaired DNA damage, and a consequent increase in genomic instability leading to cancer progression. The major goal of this study is to compare sensitivity to apoptosis induced by the bile acid, deoxycholate (DOC), a known inducer of apoptosis, in normal esophageal squamous epithelium, normal colon epithelium, and BE. METHODS: Thirteen patients with a confirmed diagnosis of BE and four patients who had undergone clinically indicated colectomy were included in the present study. Freshly obtained biopsies were incubated with control medium or medium supplemented with 1 mM DOC for 3 h and then evaluated for apoptotic changes using transmission electron microscopy and immunohistochemical staining for two apoptotic markers, cleaved caspase 3 and cleaved cytokeratin 18. RESULTS: Our results indicate that BE is resistant to apoptosis induced by DOC compared to esophageal squamous epithelium and normal colon epithelium. In addition, electron micrographs revealed mitochondrial swelling in squamous epithelial cells treated ex vivo with DOC, which was absent in epithelial cells of BE. Formation of swollen mitochondria is an early marker of apoptotic cell death. Altogether, the data indicate that reduced apoptosis capability in BE tissue may contribute to progression to esophageal adenocarcinoma.


Asunto(s)
Apoptosis/efectos de los fármacos , Esófago de Barrett/patología , Ácido Desoxicólico/farmacología , Esófago/patología , Adulto , Anciano , Esófago de Barrett/metabolismo , Biopsia , Caspasa 3 , Caspasas/análisis , Colon/patología , Epitelio/efectos de los fármacos , Epitelio/patología , Esófago/química , Esófago/ultraestructura , Humanos , Inmunohistoquímica , Técnicas In Vitro , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Queratinas/análisis , Microscopía Electrónica de Transmisión , Persona de Mediana Edad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA