Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Artículo en Inglés | MEDLINE | ID: mdl-39140310

RESUMEN

BACKGROUND: Dermatological research has traditionally concentrated on evaluating mental comorbidities, neglecting positive concepts like happiness. Initial studies indicate that psoriasis and atopic dermatitis (AD) impair the happiness of those affected. Considering global happiness variations, this study aimed to explore the disease- and country-specific differences in disease-related quality of life and happiness, and potential influential factors on heuristic happiness among psoriasis and AD patients in Europe. METHODS: A cross-sectional multicentre study was conducted in dermatology departments of university-affiliated hospitals in eight European countries (Austria, Germany, Italy, Malta, Poland, Portugal, Romania and Ukraine) between October 2021 and February 2023. Adult psoriasis and AD patients completed a standardized questionnaire in their native languages, providing data on demographics, disease-related characteristics, disease-related quality of life (Dermatology Life Quality Index, DLQI), heuristic happiness, positive affect (PA), negative affect (NA) and satisfaction with life (SWL). Descriptive analysis and quantile regression were performed. RESULTS: Between psoriasis (n = 723) and AD (n = 316) patients almost no differences were observed in happiness, SWL and NA, except for DLQI and small differences in PA, with AD patients reporting greater impact than psoriasis patients. Country-wise variation emerged in DLQI, heuristic happiness, PA, NA and SWL with Austrian patients displaying the highest levels of happiness, satisfaction and positivity, coupled with higher treatment care and lower disease severity. Quantile regression revealed varying coefficients for predictor variables across quantiles, indicating, for example positive effects on heuristic happiness associated with current or previous receipt of systemic therapies at different quantiles. CONCLUSION: This study shows notable happiness differences across European countries and significant disease-related variations, particularly with AD patients being more impaired than psoriasis patients. The findings highlight the need for equality in treatment access and support the development of targeted positive psychological interventions to enhance happiness considering country-specific distinctions in future research and health policies for psoriasis and AD patients.

2.
Hum Reprod ; 36(9): 2429-2442, 2021 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-34324672

RESUMEN

In recent years, the amount of data produced in the field of ART has increased exponentially. The diversity of data is large, ranging from videos to tabular data. At the same time, artificial intelligence (AI) is progressively used in medical practice and may become a promising tool to improve success rates with ART. AI models may compensate for the lack of objectivity in several critical procedures in fertility clinics, especially embryo and sperm assessments. Various models have been developed, and even though several of them show promising performance, there are still many challenges to overcome. In this review, we present recent research on AI in the context of ART. We discuss the strengths and weaknesses of the presented methods, especially regarding clinical relevance. We also address the pitfalls hampering successful use of AI in the clinic and discuss future possibilities and important aspects to make AI truly useful for ART.


Asunto(s)
Inteligencia Artificial , Clínicas de Fertilidad , Instituciones de Atención Ambulatoria , Humanos
3.
Heredity (Edinb) ; 118(5): 486-490, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28074845

RESUMEN

Molecular tools increasingly reveal cryptic lineages and species that were previously unnoticed by traditional taxonomy. The discovery of cryptic species in sympatry prompts the question of how they coexist in the apparent absence of ecological divergence. However, this assumes first that the molecular taxonomy used to identify cryptic lineages delimits species boundaries accurately. This issue is important, because many diversity studies rely heavily or solely on data from mitochondrial DNA sequences for species delimitation, and several factors may lead to poor identification of species boundaries. We used a multilocus population genetics approach to show that three mtDNA-defined cryptic lineages of the fig wasp Pleistodontes imperialis Saunders, which pollinate Port Jackson figs (Ficus rubiginosa) in north-eastern Australia, represent reproductively isolated species. These species coexist locally, with about 13% of figs (where mating occurs) containing wasps from two or three species. However, there was no evidence for gene flow between them. Confirmed cases of coexisting cryptic species provide excellent opportunities for future studies of the ecological and evolutionary forces shaping both species coexistence and fig/pollinator coevolution.


Asunto(s)
Ficus , Genética de Población , Aislamiento Reproductivo , Simpatría , Avispas/clasificación , Animales , Australia , ADN Mitocondrial/genética , Flujo Génico , Marcadores Genéticos , Genotipo , Hibridación Genética , Repeticiones de Microsatélite , Filogenia , Polinización , Árboles , Avispas/genética
5.
Microb Ecol ; 70(2): 498-508, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25666536

RESUMEN

Tephritid fruit fly species display a diversity of host plant specialisation on a scale from monophagy to polyphagy. Furthermore, while some species prefer ripening fruit, a few are restricted to damaged or rotting fruit. Such a diversity of host plant use may be reflected in the microbial symbiont diversity of tephritids and their grade of dependency on their microbiomes. Here, we investigated the microbiome of six tephritid species from three genera, including species that are polyphagous pests (Bactrocera tryoni, Bactrocera neohumeralis, Bactrocera jarvisi, Ceratitis capitata) and a monophagous specialist (Bactrocera cacuminata). These were compared with the microbiome of a non-pestiferous but polyphagous tephritid species that is restricted to damaged or rotting fruit (Dirioxa pornia). The bacterial community associated with whole fruit flies was analysed by 16S ribosomal DNA (rDNA) amplicon pyrosequencing to detect potential drivers of taxonomic composition. Overall, the dominant bacterial families were Enterobacteriaceae and Acetobacteraceae (both Proteobacteria), and Streptococcaceae and Enterococcaceae (both Firmicutes). Comparisons across species and genera found different microbial composition in the three tephritid genera, but limited consistent differentiation between Bactrocera species. Within Bactrocera species, differentiation of microbial composition seemed to be influenced by the environment, possibly including their diets; beyond this, tephritid species identity or ecology also had an effect. The microbiome of D. pornia was most distinct from the other five species, which may be due to its ecologically different niche of rotting or damaged fruit, as opposed to ripening fruit favoured by the other species. Our study is the first amplicon pyrosequencing study to compare the microbiomes of tephritid species and thus delivers important information about the turnover of microbial diversity within and between fruit fly species and their potential application in pest management strategies.


Asunto(s)
Tephritidae/fisiología , Animales , Australia , Bacterias/clasificación , Bacterias/genética , ARN Ribosómico 16S/genética , Tephritidae/microbiología
6.
Environ Microbiol ; 16(12): 3622-37, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24428638

RESUMEN

Wolbachia are endosymbiotic bacteria that infect 40-65% of arthropod species. They are primarily maternally inherited with occasional horizontal transmission for which limited direct ecological evidence exists. We detected Wolbachia in 8 out of 24 Australian tephritid species. Here, we have used multilocus sequence typing (MLST) to further characterize these Wolbachia strains, plus a novel quantitative polymerase chain reaction method for allele assignment in multiple infections. Based on five MLST loci and the Wolbachia surface protein gene (wsp), five Bactrocera and one Dacus species harboured two identical strains as double infections; furthermore, Bactrocera neohumeralis harboured both of these as single or double infections, and sibling species B. tryoni harboured one. Two Bactrocera species contained Wolbachia pseudogenes, potentially within the fruit fly genomes. A fruit fly parasitoid, Fopius arisanus shared identical alleles with two Wolbachia strains detected in one B. frauenfeldi individual. We report an unprecedented high incidence of four shared Wolbachia strains in eight host species from two trophic levels. This suggests frequent exposure to Wolbachia in this tropical tephritid community that shares host plant and parasitoid species, and also includes species that hybridize. Such insect communities may act as horizontal transmission platforms that contribute to the ubiquity of the otherwise maternally inherited Wolbachia.


Asunto(s)
Simbiosis , Tephritidae/microbiología , Wolbachia/clasificación , Wolbachia/aislamiento & purificación , Animales , Australia , Femenino , Incidencia , Masculino , Datos de Secuencia Molecular , Tipificación de Secuencias Multilocus , Filogenia , Reacción en Cadena de la Polimerasa , Tephritidae/genética , Tephritidae/fisiología , Avispas/microbiología , Wolbachia/genética , Wolbachia/fisiología
7.
Insect Mol Biol ; 23(6): 754-67, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25116961

RESUMEN

In tephritids, the sex-determination pathway follows the sex-specific splicing of transformer (tra) mRNA, and the cooperation of tra and transformer-2 (tra-2) to effect the sex-specific splicing of doublesex (dsx), the genetic double-switch responsible for male or female somatic development. The Dominant Male Determiner (M) is the primary signal that controls this pathway. M, as yet uncharacterized, is Y-chromosome linked, expressed in the zygote and directly or indirectly diminishes active TRA protein in male embryos. Here we first demonstrated the high conservation of tra, tra-2 and dsx in two Australian tephritids, Bactrocera tryoni and Bactrocera jarvisi. We then used quantitative reverse transcription PCR on single, sexed embryos to examine expression of the key sex-determination genes during early embryogenesis. Individual embryos were sexed using molecular markers located on the B. jarvisi Y-chromosome that was also introgressed into a B. tryoni line. In B. jarvisi, sex-specific expression of tra transcripts occurred between 3 to 6 h after egg laying, and the dsx isoform was established by 7 h. These milestones were delayed in B. tryoni lines. The results provide a time frame for transcriptomic analyses to identify M and its direct targets, plus information on genes that may be targeted for the development of male-only lines for pest management.


Asunto(s)
Expresión Génica , Procesos de Determinación del Sexo/genética , Tephritidae/genética , Animales , Australia , Secuencia de Bases , Embrión no Mamífero , Femenino , Masculino , Datos de Secuencia Molecular , Empalme del ARN , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tephritidae/embriología
8.
Oecologia ; 176(4): 1061-74, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25241296

RESUMEN

Some herbivores can modify the physiology of plant modules to meet their nutritional requirements. Induction of premature leaf senescence could benefit herbivores since it is associated with the mobilisation of nutrients. We compared the effects of nymphal feeding by Cardiaspina near densitexta on Eucalyptus moluccana with endogenous processes associated with senescence to assess the relative merits of an insect manipulation or plant defence interpretation of responses. Evidence supporting insect manipulation included increased size of fourth and fifth instar nymphs (in the latter the effect was restricted to forewing pad length of females) on leaves supporting high numbers of conspecifics and feeding preventing leaf necrosis. Intra-specific competition negated greater performance at very high densities. High and very high abundances of nymphs were associated with increased concentrations of amino acid N but only very high abundances of nymphs tended to be associated with increased concentrations of six essential amino acids. Contrary to the insect manipulation interpretation, feeding by very high abundances of nymphs was associated with significant reductions in chlorophyll, carotenoids and anthocyanins. Evidence supporting plant defence included the severity of chlorosis increasing with the abundance of nymphs. Leaf reddening did not develop because ambient conditions associated with photoinhibition (high irradiance and low temperature) were not experienced by leaves with chlorotic lesions. Leaf reddening (from anthocyanins) alone is not expected to adversely affect nymphal survival; only leaf necrosis would kill nymphs. For senescence-inducing psyllids, nutritional enhancement does not fit neatly into either an insect manipulation or plant defence interpretation.


Asunto(s)
Aminoácidos/metabolismo , Senescencia Celular , Resistencia a la Enfermedad/fisiología , Eucalyptus/fisiología , Hemípteros , Herbivoria , Hojas de la Planta/metabolismo , Animales , Antocianinas/metabolismo , Conducta Animal , Carotenoides/metabolismo , Clorofila/metabolismo , Eucalyptus/metabolismo , Femenino , Ninfa , Hojas de la Planta/fisiología
9.
Z Gastroenterol ; 52(4): 367-73, 2014 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-24718942

RESUMEN

Current endoscopic anatomy interposes the gastric cardia between the tubular oesophagus and the proximal stomach. In contrast to that, recent evidence unfolds a different view. Using "PubMed" and "Scopus" searches, we examined if the novel understanding regarding the cardia goes in line with the concept of unfolding, as described by Heidegger based on the ancient didactic poetry of Parmenides. What has been taken as gastric cardia in fact represents reflux-damaged, dilated, columnar lined oesophagus (CLO): dilated distal oesophagus (DDO). Due to its macroscopic gastric appearance it cannot be discriminated from the stomach by endoscopy. Differentiation between DDE and proximal stomach requires the histopathology of measured multi-level biopsies obtained from the DDO and the proximal stomach. Cardaic, onxytocardiac mucosa and intestinal metaplasia (IM; Barrett's oesophagus) define CLO and thus the oesophageal location, while oxyntic mucosa (OM) of the proximal stomach verifies a gastric biopsy location. Endoscopically visible CLO and DDO define the morphological manifestation of reflux: the squamo-oxyntic gap (SOG). Biopsies obtained from the level of the diaphragmatic impressions allow differentiation between an enlarged hiatus with normal anatomic content (CLO; oesophagus) vs. hernia with abnormal content (OM; stomach). Non-dysplastic Barrett's oesophagus exists in 10 %-17 % of asymptomatic and in 20 %-100 % (with increasing CLO length) of reflux symptom-positive individuals (annual cancer risk: 0.2 %-0.7 %). These data justify biopsy of an endoscopically normal appearing squamocolumnar junction for the exclusion of Barrett's oesophagus and cancer risk. In the absence of contraindications, cancer risk-based therapy of dysplastic Barrett's oesophagus includes radiofrequency ablation (RFA) ± endoscopic resection. The perception of the cardia as reflux damaged DDO mirrors the concept of unfolding, as described by the interpretation of the didactic poem of Parmenides by Heidegger. Our data recommend to omit the term "cardia" and allocate morphology either to the oesophagus (CLO, DDO) or to the proximal stomach or indicate that allocation is impossible (i. e.. tumour-induced). Future studies will have to test the value of this novel concept for diagnosis, treatment of gastro-oesophageal reflux disease and cancer prevention.


Asunto(s)
Cardias/patología , Endoscopía Gastrointestinal/métodos , Esófago/patología , Reflujo Gastroesofágico/clasificación , Reflujo Gastroesofágico/patología , Terminología como Asunto , Humanos , Internacionalidad
10.
Oecologia ; 171(4): 1025-35, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23053228

RESUMEN

Both atmospheric [CO2] and average surface temperatures are predicted to increase with potentially different, additive or opposing, effects on leaf quality and insect herbivore activity. Few studies have directly measured the interactive effects of concurrent changes in [CO2] and temperature on insect herbivores. None have done so over the entire developmental period of a tree-feeding insect, and none have compared responses to low pre-industrial [CO2] and present day [CO2] to estimate responses to future increases. Eucalypt herbivores may be particularly sensitive to climate-driven shifts in plant chemistry, as eucalypt foliage is naturally low in [N]. In this study, we assessed the development of the eucalypt herbivore Doratifera quadriguttata exposed concurrently to variable [CO2] (290, 400, 650 µmol mol(-1)) and temperature (ambient, ambient +4 °C) on glasshouse-grown Eucalyptus tereticornis. Overall, insects performed best on foliage grown at pre-industrial [CO2], indicating that modern insect herbivores have already experienced nutritional shifts since industrialisation. Rising [CO2] increased specific leaf mass and leaf carbohydrate concentration, subsequently reducing leaf [N]. Lower leaf [N] induced compensatory feeding and impeded insect performance, particularly by prolonging larval development. Importantly, elevated temperature dampened the negative effects of rising [CO2] on larval performance. Therefore, rising [CO2] over the past 200 years may have reduced forage quality for eucalypt insects, but concurrent temperature increases may have partially compensated for this, and may continue to do so in the future. These results highlight the importance of assessing plant-insect interactions within the context of multiple climate-change factors because of the interactive and potentially opposing effects of different factors within and between trophic levels.


Asunto(s)
Dióxido de Carbono/metabolismo , Cambio Climático , Eucalyptus/parasitología , Herbivoria , Mariposas Nocturnas/crecimiento & desarrollo , Temperatura , Análisis de Varianza , Animales , Eucalyptus/química , Interacciones Huésped-Parásitos/fisiología , Larva/crecimiento & desarrollo , Modelos Lineales , Nitrógeno/análisis , Hojas de la Planta/química
11.
Eur Radiol ; 22(2): 364-70, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21894565

RESUMEN

OBJECTIVES: To evaluate the diagnostic value of dynamic MRI swallowing in patients with symptoms of Gastroesophageal Reflux Disease (GERD). METHODS: Thirty-seven patients (17 m/20f) with typical signs of GERD underwent MR swallowing in the supine position at 1.5 T with a phased-array body coil. Using dynamic, gradient echo sequences (B-FFE) in the coronal, sagittal and axial planes, the bolus passages of buttermilk spiked with gadolinium chelate were tracked. MRI, pH-metry and manometry were performed within 31 days and results were compared. RESULTS: MRI results were concordant with pH-metry in 82% (23/28) of patients diagnosed with abnormal oesophageal acid exposure by pH-metry. Five patients demonstrated typical symptoms of GERD and had positive findings with pH monitoring, but false negative results with MRI. In four of six patients (67%), there was a correct diagnosis of oesophageal motility disorder, according to manometric criteria, on dynamic MRI. The overall accuracy of MRI diagnoses was 79% (27/34). A statistically significant difference was found between the size of hiatal hernia, grade of reflux in MRI, and abnormal acid exposure on pH-monitoring. CONCLUSIONS: MR fluoroscopy may be a promising radiation-free tool in assessing the functionality and morphology of the GE junction. KEY POINTS: • Swallowing MRI can assess anatomy and function of the gastroesophageal-junction • Swallowing MRI can help identifying reflux and motility disorders • Definition of the size of hiatal hernias is possible in all three planes in MR. • Short duration of swallowing MRI enables its application in routine clinical practice.


Asunto(s)
Medios de Contraste/farmacología , Trastornos de la Motilidad Esofágica/patología , Reflujo Gastroesofágico/patología , Imagen por Resonancia Magnética/métodos , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Quelantes/farmacología , Productos Lácteos Cultivados , Deglución , Trastornos de la Motilidad Esofágica/diagnóstico , Monitorización del pH Esofágico , Femenino , Gadolinio/farmacología , Reflujo Gastroesofágico/diagnóstico , Humanos , Concentración de Iones de Hidrógeno , Masculino , Manometría/métodos , Persona de Mediana Edad , Posición Supina
12.
Br J Surg ; 98(10): 1408-13, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21618213

RESUMEN

BACKGROUND: Some 10-15 per cent of patients with oesophageal cancer overexpress human epidermal growth factor receptor (HER) 2 at the primary tumour site, leading to the hope that specific targeted systemic therapy might favourably influence clinical and subclinical disease at locoregional and distant sites. This approach is based on primary tumour characteristics, without knowledge of expression patterns at metastatic sites. In oesophageal cancer, concordance between HER-2 status at the primary tumour and other sites is unknown. METHODS: The HER-2 status of primary tumours and corresponding metastatic sites (lymph node and distant) and local recurrence were evaluated in a series of patients with oesophageal cancer, using immunohistochemistry and dual colorimetric in situ hybridization. RESULTS: There were 97 adenocarcinomas (ACs) and 79 squamous cell carcinomas (SCCs). Some 14 per cent of primary ACs and 1 per cent of primary SCCs were staged as HER-2-positive. The HER-2 status was identical in the primary tumour and lymph node metastases in 95 per cent of ACs and 99 per cent of SCCs respectively (P = 0·375, sign test). Nineteen of 22 distant metastases from AC and all from SCC had identical HER-2 status to the primary tumour. In two of 22 patients with AC the primary tumour was classed as negative but distant metastases were HER-2-positive. CONCLUSION: With over 85 per cent concordance in HER-2 status between primary tumours and distant metastases in oesophageal cancer, routine HER-2 testing of metastases to confirm HER-2 positivity is not warranted. Assessment of HER-2 status at metastatic sites may be worthwhile in some patients with easily accessible metastases and negative HER-2 status at the primary tumour, or if adequate material cannot be obtained from the primary site.


Asunto(s)
Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Genes erbB-2 , Receptor ErbB-2/metabolismo , Adenocarcinoma/metabolismo , Anciano , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Amplificación de Genes/genética , Humanos , Inmunohistoquímica , Metástasis Linfática , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/metabolismo , Técnicas de Amplificación de Ácido Nucleico , Estudios Prospectivos
14.
Sci Rep ; 8(1): 7319, 2018 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-29743599

RESUMEN

Magnetic sphincter-augmentation (MSA) has been proven effective in the treatment of GERD. No consensus exists on whether crural closure should be performed. Our aim was to assess the impact of cruroplasty on reflux-control and quality of life. MSA-Patients treated between 03/2012-03/2017 were classified into those without hiatal hernia ("NHH"), those post-MSA (NHR) and those post-MSA/hiatal repair (HR). GERD-symptoms, PPI-intake, GERD-Health-related-Quality-of-Life (GERD-HRQL) and Alimentary Satisfaction were assessed. Sixty-eight patients underwent MSA, 26 patients had additional crural closure. PH-monitoring was negative in 80% of HR, 73% of NHR and 89% of NHH-patients. GERD-HRQL-total scores decreased significantly in all groups (p < 0.001). Alimentary satisfaction was 8/10 in HR/NHH and 10/10 in NHR-patients. Satisfaction with heartburn relief was high (HR: 96%, NR: 95%, NHH: 94%) as was the elimination of PPI-intake (HR/NHH: 87%, NR: 86%). Heartburn and regurgitations were eliminated in 100% of HR, 88% and 94% of NHR and 87% and 91% of NHH-patients. Endoscopic dilatation or device explantation was performed in 3% each. MSA leads to significant symptom relief, increased quality of life and alimentary satisfaction with low perioperative morbidity. Cruroplasty tends to result in better reflux control and symptom relief than exclusive MSA without increasing dysphagia rates.


Asunto(s)
Reflujo Gastroesofágico/complicaciones , Reflujo Gastroesofágico/cirugía , Hernia Hiatal/complicaciones , Campos Magnéticos , Adulto , Femenino , Pirosis/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Estudios Retrospectivos , Resultado del Tratamiento
15.
J Clin Invest ; 101(8): 1547-50, 1998 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-9541482

RESUMEN

Toxin A, a 308,000-Mr enterotoxin from Clostridium difficile, mediates antibiotic-associated diarrhea and colitis in humans. Injection of toxin A into animal intestine triggers an acute inflammatory response characterized by activation of sensory neurons and immune cells of the intestinal lamina propria, including mast cells and macrophages, and migration of circulating neutrophils in the involved intestinal segment. In this study we show that mice genetically deficient in the neurokinin-1 receptor are protected from the secretory and inflammatory changes as well as from epithelial cell damage induced by toxin A. The protective effect of neurokinin-1R deletion correlates with diminished intestinal levels of the cytokine TNF-alpha and its mRNA and the leukocyte enzyme myeloperoxidase. These results demonstrate a major requirement for substance P receptors in the pathogenesis of acute inflammatory diarrhea.


Asunto(s)
Clostridioides difficile/patogenicidad , Enterocolitis Seudomembranosa/etiología , Receptores de Neuroquinina-1/metabolismo , Animales , Toxinas Bacterianas/toxicidad , Enterocolitis Seudomembranosa/metabolismo , Enterocolitis Seudomembranosa/patología , Enterotoxinas/toxicidad , Humanos , Íleon/efectos de los fármacos , Íleon/metabolismo , Íleon/patología , Técnicas In Vitro , Ratones , Ratones Noqueados , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Neuroquinina-1/deficiencia , Receptores de Neuroquinina-1/genética , Sustancia P/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
16.
J Clin Invest ; 100(12): 3111-20, 1997 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-9399958

RESUMEN

The antifungal antibiotic clotrimazole (CLT) blocks directly and with high potency the Ca2+-activated K+ channels of human erythrocytes, erythroleukemia cells, and ferret vascular smooth muscle cells. We recently reported that CLT inhibits Cl- secretion in human intestinal T84 cells, likely by affecting K+ transport (Rufo, P.A., L. Jiang, S.J. Moe, C. Brugnara, S.L. Alper, and W.I. Lencer. 1996. J. Clin. Invest. 98:2066-2075). To determine if CLT had direct effects on K+ conductances in T84 cells, we selectively permeabilized apical membranes of confluent T84 cell monolayers using the ionophore amphotericin B. This technique permits direct measurement of basolateral K+ transport. We found that CLT and a stable des-imidazolyl derivative inhibited directly two pharmacologically distinct basolateral membrane K+conductances, but had no effect on apical membrane Cl- conductances. The effects of CLT on Cl- secretion were also examined in intact tissue. CLT inhibited forskolin-induced Cl- secretion in rabbit colonic mucosal sheets mounted in Ussing chambers by 91%. CLT also inhibited cholera toxin-induced intestinal Cl- secretion in intact mice by 94%. These data provide direct evidence that CLT blocks Cl- secretion in intestinal T84 cells by inhibition of basolateral K+ conductances, and show that CLT inhibits salt and water secretion from intact tissue in vitro and in vivo. The results further support the suggestion that CLT and its metabolites may show clinical efficacy in the treatment of secretory diarrheas of diverse etiologies.


Asunto(s)
Antifúngicos/farmacología , Cloruros/metabolismo , Clotrimazol/farmacología , Intestinos/efectos de los fármacos , Potasio/metabolismo , Animales , Calcio/metabolismo , Línea Celular , Permeabilidad de la Membrana Celular , Colforsina/farmacología , Diarrea/metabolismo , Humanos , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Intestinos/citología , Ratones , Ratones Endogámicos BALB C , Estructura Molecular , Bloqueadores de los Canales de Potasio , Canales de Potasio/metabolismo , Conejos
17.
J Clin Invest ; 95(5): 2004-11, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7738167

RESUMEN

Toxin A but not toxin B, appears to mediate intestinal damage in animal models of Clostridium difficile enteritis. The purpose of this study was to investigate the electrophysiologic and morphologic effects of purified C. difficile toxins A and B on human colonic mucosa in Ussing chambers. Luminal exposure of tissues to 16-65 nM of toxin A and 0.2-29 nM of toxin B for 5 h caused dose-dependent epithelial damage. Potential difference, short-circuit current and resistance decreased by 76, 58, and 46%, respectively, with 32 nM of toxin A and by 76, 55, and 47%, respectively, with 3 nM of toxin B, when compared with baseline (P < 0.05). 3 nM of toxin A did not cause electrophysiologic changes. Permeability to [3H]mannitol increased 16-fold after exposure to 32 nM of toxin A and to 3 nM of toxin B when compared with controls (P < 0.05). Light and scanning electron microscopy after exposure to either toxin revealed patchy damage and exfoliation of superficial epithelial cells, while crypt epithelium remained intact. Fluorescent microscopy of phalloidin-stained sections showed that both toxins caused disruption and condensation of cellular F-actin. Our results demonstrate that the human colon is approximately 10 times more sensitive to the damaging effects of toxin B than toxin A, suggesting that toxin B may be more important than toxin A in the pathogenesis of C. difficile colitis in man.


Asunto(s)
Proteínas Bacterianas , Toxinas Bacterianas/toxicidad , Colon , Enterotoxinas/toxicidad , Mucosa Intestinal/efectos de los fármacos , Actinas/efectos de los fármacos , Actinas/metabolismo , Transporte Biológico/efectos de los fármacos , Permeabilidad de la Membrana Celular/efectos de los fármacos , Clostridioides difficile , Citotoxinas/toxicidad , Electrofisiología , Epitelio/efectos de los fármacos , Epitelio/fisiología , Epitelio/ultraestructura , Humanos , Mucosa Intestinal/citología , Mucosa Intestinal/fisiología , Cinética , Manitol/metabolismo , Potenciales de la Membrana/efectos de los fármacos , Microscopía Electrónica de Rastreo , Factores de Tiempo
18.
Eur Surg ; 49(6): 279-281, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29250105

RESUMEN

INTRODUCTION: Barrett's esophagus (BE) represents the premalignant morphology of gastroesophageal reflux disease (GERD). Evidence indicates a positive correlation between GERD vs. obesity and increased sugar consumption. METHODS: Here we analyzed recently published data (2006-2017) on the role of dietary sugar intake for BE development (main focus year 2017). RESULTS: Recent investigations found a positive association between obesity, hip waist ratio and dietary sugar intake and Barrett's esophagus. CONCLUSION: Sugar intake positively associates with BE. A low carbohydrate diet should be recommended for persons with BE and GERD.

19.
Eur Surg ; 49(6): 282-287, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29250106

RESUMEN

BACKGROUND: Barrett's esophagus (BE) is the premalignant manifestation of gastroesophageal reflux disease (GERD). Radiofrequency ablation (RFA) with and without endoscopic resection (ER) is a novel treatment for BE. METHODS: Here we present a single-center update of the recommendations of a recent (June 2015) interdisciplinary expert panel meeting on the management of BE with dysplasia as well as cancer-positive and cancer-negative BE. We conducted a PubMed search of studies published in 2016 and 2017 on the topic of BE and RFA. RESULTS: Our update reconfirms that BE positive for T1a cancer as well as low- and high-grade dysplasia justifies the use of RFA ± ER, offering an 80-100% rate of BE clearance. RFA ± ER of dysplastic BE is tenfold more effective for cancer prevention when compared with surveillance. Risk factors for recurrence and follow-up treatments include baseline histopathology (dysplasia/T1a cancer), esophagitis, hiatal hernia >3 cm, smoking habits, BE segments >3 cm, and >10 years of GERD symptoms. A baseline diagnosis for dysplasia and T1a cancer should include a second expert pathologist opinion. Recent data justify the use of RFA for nondysplastic BE only in controlled clinical trials. Antireflux surgery can be offered to those with function-test-proven, GERD-symptom-positive BE before, during, or after RFA ± ER. Additionally, there is growing evidence that the intake of a sugar-rich diet is positively correlated with the development of GERD, BE, and cancer. CONCLUSION: RFA ± ER should be offered for dysplastic BE and T1a cancer after ER as well as for nondysplastic BE with additional risk factors in controlled trials. Antireflux surgery can be offered to patients with function-test-proven GERD-symptom-positive BE. Diet considerations should be included in the management of GERD and BE.

20.
Artículo en Inglés | MEDLINE | ID: mdl-28133854

RESUMEN

BACKGROUND: Obesity and gastroesophageal reflux disease (GERD) are major health problems showing an inconstant relationship in the literature. Therefore, anthropometric parameters which are predictive and can simply be assessed at first patient presentation may lead to a better patient selection for ambulatory reflux monitoring. We aimed to examine the association of body mass index (BMI) and waist to hip ratio (WHR) with gastroesophageal reflux activity during 24 hour-pH-impedance monitoring. METHODS: Seven hundred and seventy-one patients with GERD symptoms underwent 24 hour-pH-impedance monitoring and high resolution manometry off proton pump inhibitors. Patients with known primary motility disorders of the esophagus and pre-existing endoscopic or operative procedure on esophagus or stomach were excluded from the study. Reflux parameters and anthropometric and demographic data from our prospectively gathered database were analyzed. We performed univariate and multivariate regression analysis to evaluate the associations of BMI and WHR with reflux parameters measured with 24 hour-pH-impedance monitoring. KEY RESULTS: WHR showed a significantly stronger association with esophageal acid exposure than BMI (P<.001). Our data show that 6.9% of the percentage of endoluminal pH<4 in the distal esophagus is attributable to WHR. Furthermore, an association of WHR with impaired esophageal acid clearance was observed. Additionally, we observed an inverse relationship between lower esophageal sphincter integrity (P=.05) and esophageal acid exposure. CONCLUSIONS AND INFERENCES: WHR is a better predictor for esophageal acid exposure than BMI. Biomechanical and metabolic mechanisms of central fat distribution may influence reflux parameters in 24 hour pH impedance monitoring, which may affect patient selection for ambulatory reflux monitoring.


Asunto(s)
Índice de Masa Corporal , Monitorización del pH Esofágico/normas , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/fisiopatología , Relación Cintura-Cadera/normas , Adulto , Monitorización del pH Esofágico/métodos , Femenino , Reflujo Gastroesofágico/etiología , Humanos , Masculino , Manometría/métodos , Manometría/normas , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/diagnóstico , Obesidad/fisiopatología , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Relación Cintura-Cadera/métodos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA