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[PMID]:28375482
[Au] Autor:Su A; Gandhy R; Barlow C; Triadafilopoulos G
[Ad] Dirección:Medicine, Stanford University School of Medicine, Stanford, CA, USA.
[Ti] Título:Clinical and manometric characteristics of patients with Parkinson's disease and esophageal symptoms.
[So] Fuente:Dis Esophagus;30(4):1-6, 2017 Apr 01.
[Is] ISSN:1442-2050
[Cp] País de publicación:United States
[La] Idioma:eng
[Ab] Resumen:Dysphagia is a common problem in patients with Parkinson's disease (PD); its etiology is multifactorial and its management is challenging. In this retrospective cohort analysis using prospectively collected data, we aimed to objectively characterize dysphagia and/or other esophageal symptoms in patients with PD, assess the prevalence of outflow obstruction as well as major or minor disorders of esophageal peristalsis leading to impaired esophageal clearance and highlight objective parameters that can help in the current management algorithm. Thirty-three consecutive patients with PD presenting with dysphagia, odynophagia, heartburn, regurgitation, chest pain, and weight loss underwent clinical and functional evaluation by high-resolution manometry (HRM). Esophagogastric junction (EGJ) outflow obstruction and major as well as minor disorders of peristalsis were then assessed using the Chicago classification (v3). Thirty-three PD patients with esophageal symptoms were enrolled in the study; 12 of them reported weight loss that was considered as potentially reflecting underlying esophageal dysfunction. The median age of the patients was 70 years (range: 53-89 years), 24 (75%) were men. The majority (62%) experienced dysphagia, likely contributing to weight loss in 41% of patients. Odynophagia was rare (6%) while GER symptoms, such as heartburn, regurgitation, and chest pain were noted in 37%, 31%, and 28% of patients, respectively. Using the hierarchy of the Chicago classification, 12 patients (39%) exhibited EGJ outflow obstruction, 16 (48%) diffuse esophageal spasm (DES), 18 (55%), ineffective esophageal peristalsis (IEM), 16 (48%) fragmented peristalsis, and only 2 patients (6%) had normal HRM tracings. There were no patients with HRM features of achalasia. Dysphagia is common in patients with PD and is associated with a high prevalence of underlying motility disturbances as identified by HRM. The exact impact of these motility abnormalities on symptom induction and their role in influencing clinical management are unclear and will require further study.
[Mh] Términos MeSH primario: Trastornos de Deglución/etiología
Manejo de la Enfermedad
Esófago/fisiopatología
Manometría/métodos
Enfermedad de Parkinson/complicaciones
[Mh] Términos MeSH secundario: Anciano
Anciano de 80 o más Años
Algoritmos
Dolor en el Pecho/etiología
Dolor en el Pecho/fisiopatología
Trastornos de Deglución/fisiopatología
Unión Esofagogástrica/fisiopatología
Femenino
Pirosis/etiología
Pirosis/fisiopatología
Humanos
Reflujo Laringofaríngeo/etiología
Reflujo Laringofaríngeo/fisiopatología
Masculino
Mediana Edad
Enfermedad de Parkinson/fisiopatología
Peristaltismo/fisiología
Estudios Prospectivos
Estudios Retrospectivos
Pérdida de Peso
[Pt] Tipo de publicación:JOURNAL ARTICLE
[Em] Mes de ingreso:1710
[Cu] Fecha actualización por clase:171011
[Lr] Fecha última revisión:171011
[Sb] Subgrupo de revista:IM
[Da] Fecha de ingreso para procesamiento:170404
[St] Status:MEDLINE
[do] DOI:10.1093/dote/dow038


  2 / 3604 MEDLINE  
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[PMID]:28325440
[Au] Autor:Hayat T; Farooq S; Alsaedi A
[Ad] Dirección:Department of Mathematics, Quaid-I-Azam University 45320, Islamabad 44000, Pakistan; Nonlinear Analysis and Applied Mathematics (NAAM) Research Group, Department of Mathematics, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
[Ti] Título:Mixed convection peristaltic motion of copper-water nanomaterial with velocity slip effects in a curved channel.
[So] Fuente:Comput Methods Programs Biomed;142:117-128, 2017 Apr.
[Is] ISSN:1872-7565
[Cp] País de publicación:Ireland
[La] Idioma:eng
[Ab] Resumen:BACKGROUND AND OBJECTIVE: The primary objective of present analysis is to model the peristalsis of copper-water based nanoliquid in the presence of first order velocity and thermal slip conditions in a curved channel. Mixed convection, viscous dissipation and heat generation/absorption are also accounted. METHOD: Mathematical formulation is simplified under the assumption of small Reynolds number and large wavelength. Regular perturbation technique is employed to find the solution of the resulting equations in terms of series for small Brinkman number. The final expression for pressure gradient, pressure rise, stream function, velocity and temperature are obtained and discussed through graphs. Mathematica software is utilized to compute the solution of the system of equations and to plot the graphical results. RESULTS: Results indicates that insertion of 30% copper nanoparticles in the basefluid (water) velocity and temperature reduces by almost 3% and 40% respecively. Moreover it is seen that size of the trapped bolus also reduces almost 20% with the insertion of 20% nanoparticles (copper) in the basefluid (water). CONCLUSION: It is noted that velocity and temperature are decreasing functions of nanoparticle volume fraction. Moreover the temperature rises when heat generation parameter and Brinkman number are enhanced.
[Mh] Términos MeSH primario: Cobre/química
Nanoestructuras/química
Peristaltismo
Agua/química
[Mh] Términos MeSH secundario: Simulación por Computador
Convección
Sistemas de Liberación de Medicamentos
Calor
Nanopartículas del Metal
Modelos Teóricos
Movimiento (Física)
Presión
Reología
Programas Informáticos
Viscosidad
[Pt] Tipo de publicación:JOURNAL ARTICLE
[Nm] Nombre de substancia:
059QF0KO0R (Water); 789U1901C5 (Copper)
[Em] Mes de ingreso:1710
[Cu] Fecha actualización por clase:171002
[Lr] Fecha última revisión:171002
[Sb] Subgrupo de revista:IM
[Da] Fecha de ingreso para procesamiento:170322
[St] Status:MEDLINE


  3 / 3604 MEDLINE  
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[PMID]:28192805
[Au] Autor:Takahashi K; Ishii Y; Hayashi K; Ikarashi S; Kawai H; Sato Y; Terai S
[Ad] Dirección:Division of Gastroenterology and Hepatology, Graduate School of Medical and Dental Science, Niigata University, Niigata, Japan.
[Ti] Título:Loss of peristalsis of the esophagus due to diffuse esophageal leiomyomatosis.
[So] Fuente:Endoscopy;49(S 01):E95-E96, 2017 Feb.
[Is] ISSN:1438-8812
[Cp] País de publicación:Germany
[La] Idioma:eng
[Mh] Términos MeSH primario: Neoplasias Esofágicas/fisiopatología
Esófago/fisiopatología
Leiomiomatosis/fisiopatología
Peristaltismo
[Mh] Términos MeSH secundario: Adolescente
Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico
Neoplasias Esofágicas/diagnóstico por imagen
Neoplasias Esofágicas/patología
Esófago/diagnóstico por imagen
Femenino
Humanos
Leiomiomatosis/diagnóstico por imagen
Leiomiomatosis/patología
Imagen por Resonancia Magnética
Tomografía Computarizada por Rayos X
[Pt] Tipo de publicación:CASE REPORTS; JOURNAL ARTICLE
[Em] Mes de ingreso:1709
[Cu] Fecha actualización por clase:170928
[Lr] Fecha última revisión:170928
[Sb] Subgrupo de revista:IM
[Da] Fecha de ingreso para procesamiento:170213
[St] Status:MEDLINE
[do] DOI:10.1055/s-0043-100691


  4 / 3604 MEDLINE  
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[PMID]:28188734
[Au] Autor:Yang J; Shimogonya Y; Ishikawa T
[Ad] Dirección:Department of Biomedical Engineering, Graduate School of Biomedical Engineering, Tohoku University, 6-6-01 Aoba, Sendai 980-8579, Japan. Electronic address: yang@pfsl.mech.tohoku.ac.jp.
[Ti] Título:Mixing and pumping functions of the intestine of zebrafish larvae.
[So] Fuente:J Theor Biol;419:152-158, 2017 Apr 21.
[Is] ISSN:1095-8541
[Cp] País de publicación:England
[La] Idioma:eng
[Ab] Resumen:Due to its transparency, the intestine of zebrafish larvae has been widely used in studies of gastrointestinal diseases and the microbial flora of the gut. However, transport phenomena in the intestine of zebrafish larvae have not been fully clarified. In this study, therefore, transport caused by peristaltic motion in the intestine of zebrafish larvae was investigated by numerical simulation. An anatomically realistic three-dimensional geometric model of the intestine at various times after feeding was constructed based on the experimental data of Field et al. (2009). The flow of digested chyme was analyzed using the governing equations of fluid mechanics, together with peristaltic motion and long-term contraction of the intestinal wall. The results showed that retrograde peristaltic motion was the main contributor to the mixing function. The dispersion caused by peristalsis over 30min was in the order of 10 m /s, which is greater than the Brownian diffusion of a sphere of 0.4µm diameter. In contrast, anterograde peristaltic motion contributed mainly to the pumping function. The pressure decrease due to peristalsis was in the order of millipascals, which may reduce the activation and maintenance heat of intestinal muscle. These findings enhance our understanding of the mixing and pumping functions of the intestine of zebrafish larvae.
[Mh] Términos MeSH primario: Algoritmos
Intestinos/fisiología
Modelos Biológicos
Peristaltismo/fisiología
Pez Cebra/fisiología
[Mh] Términos MeSH secundario: Animales
Larva/fisiología
Movimiento (Física)
Presión
Factores de Tiempo
[Pt] Tipo de publicación:JOURNAL ARTICLE
[Em] Mes de ingreso:1709
[Cu] Fecha actualización por clase:170925
[Lr] Fecha última revisión:170925
[Sb] Subgrupo de revista:IM
[Da] Fecha de ingreso para procesamiento:170211
[St] Status:MEDLINE


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[PMID]:28762235
[Au] Autor:Lai NM; Ahmad Kamar A; Choo YM; Kong JY; Ngim CF
[Ad] Dirección:School of Medicine, Taylor's University, Subang Jaya, Malaysia.
[Ti] Título:Fluid supplementation for neonatal unconjugated hyperbilirubinaemia.
[So] Fuente:Cochrane Database Syst Rev;8:CD011891, 2017 08 01.
[Is] ISSN:1469-493X
[Cp] País de publicación:England
[La] Idioma:eng
[Ab] Resumen:BACKGROUND: Neonatal hyperbilirubinaemia is a common problem which carries a risk of neurotoxicity. Certain infants who have hyperbilirubinaemia develop bilirubin encephalopathy and kernicterus which may lead to long-term disability. Phototherapy is currently the mainstay of treatment for neonatal hyperbilirubinaemia. Among the adjunctive measures to compliment the effects of phototherapy, fluid supplementation has been proposed to reduce serum bilirubin levels. The mechanism of action proposed includes direct dilutional effects of intravenous (IV) fluids, or enhancement of peristalsis to reduce enterohepatic circulation by oral fluid supplementation. OBJECTIVES: To assess the risks and benefits of fluid supplementation compared to standard fluid management in term and preterm newborn infants with unconjugated hyperbilirubinaemia who require phototherapy. SEARCH METHODS: We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 5), MEDLINE via PubMed (1966 to 7 June 2017), Embase (1980 to 7 June 2017), and CINAHL (1982 to 7 June 2017). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. SELECTION CRITERIA: We included randomised controlled trials that compared fluid supplementation against no fluid supplementation, or one form of fluid supplementation against another. DATA COLLECTION AND ANALYSIS: We extracted data using the standard methods of the Cochrane Neonatal Review Group using the Covidence platform. Two review authors independently assessed the eligibility and risk of bias of the retrieved records. We expressed our results using mean difference (MD), risk difference (RD), and risk ratio (RR) with 95% confidence intervals (CIs). MAIN RESULTS: Out of 1449 articles screened, seven studies were included. Three articles were awaiting classification, among them, two completed trials identified from the trial registry appeared to be unpublished so far.There were two major comparisons: IV fluid supplementation versus no fluid supplementation (six studies) and IV fluid supplementation versus oral fluid supplementation (one study). A total of 494 term, healthy newborn infants with unconjugated hyperbilirubinaemia were evaluated. All studies were at high risk of bias for blinding of care personnel, five studies had unclear risk of bias for blinding of outcome assessors, and most studies had unclear risk of bias in allocation concealment. There was low- to moderate-quality evidence for all major outcomes.In the comparison between IV fluid supplementation and no supplementation, no infant in either group developed bilirubin encephalopathy in the one study that reported this outcome. Serum bilirubin was lower at four hours postintervention for infants who received IV fluid supplementation (MD -34.00 µmol/L (-1.99 mg/dL), 95% CI -52.29 (3.06) to -15.71 (0.92); participants = 67, study = 1) (low quality of evidence, downgraded one level for indirectness and one level for suspected publication bias). Beyond eight hours postintervention, serum bilirubin was similar between the two groups. Duration of phototherapy was significantly shorter for fluid-supplemented infants, but the estimate was affected by heterogeneity which was not clearly explained (MD -10.70 hours, 95% CI -15.55 to -5.85; participants = 218; studies = 3; I² = 67%). Fluid-supplemented infants were less likely to require exchange transfusion (RR 0.39, 95% CI 0.21 to 0.71; RD -0.01, 95% CI -0.04 to 0.02; participants = 462; studies = 6; I² = 72%) (low quality of evidence, downgraded one level due to inconsistency, and another level due to suspected publication bias), and the estimate was similarly affected by unexplained heterogeneity. The frequencies of breastfeeding were similar between the fluid-supplemented and non-supplemented infants in days one to three based on one study (estimate on day three: MD 0.90 feeds, 95% CI -0.40 to 2.20; participants = 60) (moderate quality of evidence, downgraded one level for imprecision).One study contributed to all outcome data in the comparison of IV versus oral fluid supplementation. In this comparison, no infant in either group developed abnormal neurological signs. Serum bilirubin, as well as the rate of change of serum bilirubin, were similar between the two groups at four hours after phototherapy (serum bilirubin: MD 11.00 µmol/L (0.64 mg/dL), 95% CI -21.58 (-1.26) to 43.58 (2.55); rate of change of serum bilirubin: MD 0.80 µmol/L/hour (0.05 mg/dL/hour), 95% CI -2.55 (-0.15) to 4.15 (0.24); participants = 54 in both outcomes) (moderate quality of evidence for both outcomes, downgraded one level for indirectness). The number of infants who required exchange transfusion was similar between the two groups (RR 1.60, 95% CI 0.60 to 4.27; RD 0.11, 95% CI -0.12 to 0.34; participants = 54). No infant in either group developed adverse effects including vomiting or abdominal distension. AUTHORS' CONCLUSIONS: There is no evidence that IV fluid supplementation affects important clinical outcomes such as bilirubin encephalopathy, kernicterus, or cerebral palsy in healthy, term newborn infants with unconjugated hyperbilirubinaemia requiring phototherapy. In this review, no infant developed these bilirubin-associated clinical complications. Low- to moderate-quality evidence shows that there are differences in total serum bilirubin levels between fluid-supplemented and control groups at some time points but not at others, the clinical significance of which is uncertain. There is no evidence of a difference between the effectiveness of IV and oral fluid supplementations in reducing serum bilirubin. Similarly, no infant developed adverse events or complications from fluid supplementation such as vomiting or abdominal distension. This suggests a need for future research to focus on different population groups with possibly higher baseline risks of bilirubin-related neurological complications, such as preterm or low birthweight infants, infants with haemolytic hyperbilirubinaemia, as well as infants with dehydration for comparison of different fluid supplementation regimen.
[Mh] Términos MeSH primario: Fluidoterapia/efectos adversos
Hiperbilirrubinemia Neonatal/terapia
Kernicterus/prevención & control
Fototerapia
[Mh] Términos MeSH secundario: Administración Intravenosa
Administración Oral
Bilirrubina/sangre
Lactancia Materna/estadística & datos numéricos
Parálisis Cerebral/prevención & control
Recambio Total de Sangre/estadística & datos numéricos
Fluidoterapia/métodos
Humanos
Hiperbilirrubinemia Neonatal/sangre
Recién Nacido
Peristaltismo
Fototerapia/métodos
Fototerapia/estadística & datos numéricos
Factores de Tiempo
[Pt] Tipo de publicación:JOURNAL ARTICLE; META-ANALYSIS; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; REVIEW
[Nm] Nombre de substancia:
RFM9X3LJ49 (Bilirubin)
[Em] Mes de ingreso:1709
[Cu] Fecha actualización por clase:170919
[Lr] Fecha última revisión:170919
[Sb] Subgrupo de revista:IM
[Da] Fecha de ingreso para procesamiento:170801
[St] Status:MEDLINE
[do] DOI:10.1002/14651858.CD011891.pub2


  6 / 3604 MEDLINE  
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[PMID]:28542509
[Au] Autor:Huh CW; Youn YH; Chung H; Lee YC; Park H
[Ad] Dirección:Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
[Ti] Título:Functional restoration of the esophagus after peroral endoscopic myotomy for achalasia.
[So] Fuente:PLoS One;12(5):e0178414, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicación:United States
[La] Idioma:eng
[Ab] Resumen:PURPOSE: Peroral endoscopic myotomy (POEM) is a new efficacious treatment option for achalasia. We propose to define "esophageal remodeling" as the functional restoration of the esophagus that involves decreased lower esophageal sphincter (LES) pressure, recovery of esophageal body peristalsis, and reduction of luminal diameter. The aim of this study was to investigate "esophageal remodeling" after POEM for achalasia. MATERIALS AND METHODS: We analyzed data from a prospectively collected database of POEM subjects, which included preoperative and 2-month postoperative Eckardt symptom scores, and results from esophageal high resolution manometry (HRM) and barium esophagogram (BE). We recruited 23 patients (13 male; mean age: 53.9 years) whose preoperative and postoperative HRM and BE results were available, from among 30 patients with achalasia who underwent POEM at two institutions between July 2013 and December 2015. RESULTS: All patients achieved clinical treatment success (Eckardt score≤3). Partial recovery of esophageal body peristalsis was noted in 1/5 patients with type I (20%), 6/11 with type II (54.5%), and 7/7 with type III (100%) achalasia after POEM. Pan-esophageal pressurization disappeared after POEM in 10/11 type II achalasia patients. The average diameter of the esophageal body after POEM was significantly decreased in all types of achalasia. CONCLUSION: POEM provided excellent clinical symptomatic relief and esophageal remodeling in terms of restoration of peristalsis and reduction in diameter of the esophageal body, especially in patients with type III achalasia.
[Mh] Términos MeSH primario: Acalasia del Esófago/cirugía
Esofagoscopía
Esófago/cirugía
Cirugía Endoscópica por Orificios Naturales
Recuperación de la Función
[Mh] Términos MeSH secundario: Adulto
Anciano
Anciano de 80 o más Años
Acalasia del Esófago/patología
Acalasia del Esófago/fisiopatología
Esófago/patología
Esófago/fisiopatología
Femenino
Humanos
Masculino
Manometría
Mediana Edad
Músculo Liso/patología
Músculo Liso/fisiopatología
Músculo Liso/cirugía
Tamaño de los Órganos
Peristaltismo
Estudios Prospectivos
Estudios Retrospectivos
Índice de Severidad de la Enfermedad
Resultado del Tratamiento
Adulto Joven
[Pt] Tipo de publicación:JOURNAL ARTICLE
[Em] Mes de ingreso:1709
[Cu] Fecha actualización por clase:170918
[Lr] Fecha última revisión:170918
[Sb] Subgrupo de revista:IM
[Da] Fecha de ingreso para procesamiento:170525
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0178414


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[PMID]:28550489
[Au] Autor:Frazzoni M; de Bortoli N; Frazzoni L; Tolone S; Savarino V; Savarino E
[Ad] Dirección:Digestive Pathophysiology Unit, Baggiovara Hospital, Viale Giardini 1355, 41100, Modena, Italy. marziofrazzoni@gmail.com.
[Ti] Título:Impedance-pH Monitoring for Diagnosis of Reflux Disease: New Perspectives.
[So] Fuente:Dig Dis Sci;62(8):1881-1889, 2017 Aug.
[Is] ISSN:1573-2568
[Cp] País de publicación:United States
[La] Idioma:eng
[Ab] Resumen:Heartburn is the most specific symptom of gastroesophageal reflux disease (GERD). In clinical practice, heartburn relief by a proton pump inhibitor (PPI) trial does suffice to confirm GERD. However, an objective diagnosis of GERD is required before anti-reflux endoscopic or surgical interventions, independently from PPI response. Thus, since normal findings at upper endoscopy are detected in the majority of patients with heartburn, reflux monitoring is often required. When traditional catheter-based or wireless pH tests are used, reflux episodes are conventionally identified by pH drops below 4.0 units. Combined impedance-pH monitoring has the advantage to provide a comprehensive assessment of both physical and chemical properties of refluxate and the distinction between acid and weakly acidic refluxes, both proven to cause heartburn. Unfortunately, the conventional impedance-pH parameters, namely acid exposure time and number of reflux events, are characterized by suboptimal diagnostic sensitivity, and the reliability of symptom-reflux association indexes remains questionable. Therefore, novel impedance parameters, namely the post-reflux swallow-induced peristaltic wave (PSPW) index and the mean nocturnal baseline impedance (MNBI), have recently been proposed in order to achieve a better diagnostic yield. In fact, they proved to be highly accurate in distinguishing reflux-related from reflux-unrelated heartburn, off- as well as on-PPI therapy. Currently, manual review of impedance-pH tracings is needed because of the modest accuracy of available software tools for automated analysis. PSPW index and MNBI are highly applicable and reproducible, and their calculation requires a few additional minutes during the manual review of impedance-pH tracings. So far, we believe that PSPW index and MNBI are ready for prime time and should become part of the standard analysis of impedance-pH tracings for GERD diagnosis in patients with endoscopy-negative heartburn.
[Mh] Términos MeSH primario: Impedancia Eléctrica
Monitorización del pH Esofágico/métodos
Reflujo Gastroesofágico/diagnóstico
[Mh] Términos MeSH secundario: Esófago/química
Esófago/fisiopatología
Reflujo Gastroesofágico/complicaciones
Reflujo Gastroesofágico/fisiopatología
Pirosis/quimioterapia
Pirosis/etiología
Humanos
Concentración de Iones de Hidrógeno
Peristaltismo
Inhibidores de la Bomba de Protones/uso terapéutico
Reproducibilidad de Resultados
[Pt] Tipo de publicación:JOURNAL ARTICLE; REVIEW
[Nm] Nombre de substancia:
0 (Proton Pump Inhibitors)
[Em] Mes de ingreso:1709
[Cu] Fecha actualización por clase:170906
[Lr] Fecha última revisión:170906
[Sb] Subgrupo de revista:AIM; IM
[Da] Fecha de ingreso para procesamiento:170527
[St] Status:MEDLINE
[do] DOI:10.1007/s10620-017-4625-8


  8 / 3604 MEDLINE  
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[PMID]:28222160
[Au] Autor:Hayat T; Zahir H; Tanveer A; Alsaedi A
[Ad] Dirección:Department of Mathematics, Quaid-I-Azam University 45320, Islamabad 44000, Pakistan.
[Ti] Título:Soret and Dufour effects on MHD peristaltic transport of Jeffrey fluid in a curved channel with convective boundary conditions.
[So] Fuente:PLoS One;12(2):e0164854, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicación:United States
[La] Idioma:eng
[Ab] Resumen:The purpose of present article is to examine the peristaltic flow of Jeffrey fluid in a curved channel. An electrically conducting fluid in the presence of radial applied magnetic field is considered. Analysis of heat and mass transfer is carried out. More generalized realistic constraints namely the convective conditions are utilized. Soret and Dufour effects are retained. Problems formulation is given for long wavelength and low Reynolds number assumptions. The expressions of velocity, temperature, heat transfer coefficient, concentration and stream function are computed. Effects of emerging parameters arising in solutions are analyzed in detail. It is found that velocity is not symmetric about centreline for curvature parameter. Also maximum velocity decreases with an increase in the strength of magnetic field. Further it is noticed that Soret and Dufour numbers have opposite behavior for temperature and concentration.
[Mh] Términos MeSH primario: Reología
Temperatura Ambiental
[Mh] Términos MeSH secundario: Convección
Difusión
Conductividad Eléctrica
Diseño de Equipo
Campos Magnéticos
Concentración Osmolar
Peristaltismo
Soluciones
[Pt] Tipo de publicación:JOURNAL ARTICLE
[Nm] Nombre de substancia:
0 (Solutions)
[Em] Mes de ingreso:1708
[Cu] Fecha actualización por clase:170821
[Lr] Fecha última revisión:170821
[Sb] Subgrupo de revista:IM
[Da] Fecha de ingreso para procesamiento:170221
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0164854


  9 / 3604 MEDLINE  
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[PMID]:28336550
[Au] Autor:Broers C; Melchior C; Van Oudenhove L; Vanuytsel T; Van Houtte B; Scheerens C; Rommel N; Tack J; Pauwels A
[Ad] Dirección:Translational Research Center for Gastrointestinal Disorders, Department of Clinical and Experimental Medicine, KU Leuven, Belgium.
[Ti] Título:The effect of intravenous corticotropin-releasing hormone administration on esophageal sensitivity and motility in health.
[So] Fuente:Am J Physiol Gastrointest Liver Physiol;312(5):G526-G534, 2017 May 01.
[Is] ISSN:1522-1547
[Cp] País de publicación:United States
[La] Idioma:eng
[Ab] Resumen:Esophageal hypersensitivity is important in gastroesophageal reflux disease (GERD) patients who are refractory to acid-suppressive therapy. Stress affects visceral sensitivity and exacerbates heartburn in GERD. Peripheral CRH is a key mediator of the gut stress response. We hypothesize that CRH increases esophageal sensitivity and alters esophageal motility in health. Esophageal sensitivity to thermal, mechanical, electrical, and chemical stimuli was assessed in 14 healthy subjects after administration of placebo or CRH (100 µg iv). Perception scores were assessed for first perception, pain perception threshold (PPT), and pain tolerance threshold (PTT). Esophageal motility was investigated by high-resolution impedance manometry, before and after CRH and evaluated by distal contractile integral (DCI) and intrabolus pressure (IBP). Pressure flow analysis assessed bolus clearance (impedance ratio), degree of pressurization needed to propel bolus onward (IBP slope), and pressure flow (pressure flow index, PFI). Stress and mood were assessed during the study. Sensitivity to mechanical distention was increased after CRH compared with placebo (PPT: = 0.0023; PTT: = 0.0253). CRH had no influence on the other stimulations. DCI was increased for all boluses (liquid, = 0.0012; semisolid, = 0.0017; solid, = 0.0107). Impedance ratio for liquid ( < 0.0001) and semisolid swallows ( = 0.0327) decreased after CRH. IBP slope increased after CRH for semisolid ( = 0.0041) and solid ( = 0.0003) swallows. PFI increased for semisolid ( = 0.0017) and solid swallows ( = 0.0031). CRH increased esophageal sensitivity to mechanical distention, not to the other stimulation modalities. CRH increased esophageal contractility and tone, decreased LES relaxation, increased esophageal bolus pressurization, improved esophageal bolus clearance, and increased pressure flow. This is the first study to address the effect of corticotropin-releasing hormone (CRH) on esophageal sensitivity and alterations in motility in health. CRH administration increased esophageal sensitivity to mechanical distention. This effect is accompanied by an increase in esophageal contractility and tone and a decrease in lower esophageal sphincter relaxation. CRH increased esophageal bolus pressurization, improved esophageal bolus clearance, and increased pressure flow. The changes in esophageal contractile properties may underlie the increased sensitivity to mechanical distention after CRH.
[Mh] Términos MeSH primario: Hormona Liberadora de Corticotropina/administración & dosificación
Deglución/fisiología
Esófago/efectos de drogas
Esófago/fisiología
Motilidad Gastrointestinal/fisiología
Peristaltismo/fisiología
[Mh] Términos MeSH secundario: Adolescente
Adulto
Deglución/efectos de drogas
Relación Dosis-Respuesta a Droga
Femenino
Motilidad Gastrointestinal/efectos de drogas
Humanos
Inyecciones Intravenosas
Masculino
Mediana Edad
Peristaltismo/efectos de drogas
Presión
Adulto Joven
[Pt] Tipo de publicación:CLINICAL TRIAL; JOURNAL ARTICLE
[Nm] Nombre de substancia:
9015-71-8 (Corticotropin-Releasing Hormone)
[Em] Mes de ingreso:1708
[Cu] Fecha actualización por clase:170818
[Lr] Fecha última revisión:170818
[Sb] Subgrupo de revista:IM
[Da] Fecha de ingreso para procesamiento:170324
[St] Status:MEDLINE
[do] DOI:10.1152/ajpgi.00437.2016


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[PMID]:28254773
[Au] Autor:Kern MK; Balasubramanian G; Sanvanson P; Agrawal D; Wuerl A; Shaker R
[Ad] Dirección:Division of Gastroenterology and Hepatology, Medical College of Wisconsin, Milwaukee, Wisconsin.
[Ti] Título:Pharyngeal peristaltic pressure variability, operational range, and functional reserve.
[So] Fuente:Am J Physiol Gastrointest Liver Physiol;312(5):G516-G525, 2017 May 01.
[Is] ISSN:1522-1547
[Cp] País de publicación:United States
[La] Idioma:eng
[Ab] Resumen:The present understanding of pharyngeal motor function remains incomplete. Among the remaining gaps of knowledge in this regard is the magnitude of variability of pharyngeal peristaltic pressure amplitude. Although variability can pose difficulty in interpretation of manometric findings, its magnitude can inform the operational range and reserve of the pharyngeal contractile function. We aimed to define the intra- and intersubject and intersession variability of select pharyngeal manometric parameters and, using this information, determine the number of swallow repetitions for acquiring reliable pharyngeal manometric data. We recorded pharyngeal peristalsis in 10 healthy subjects (age: 50 ± 25 yr, 5 women) by high-resolution manometry during two separate sessions of 20 sequences of 0.5-ml water swallows. Two-way ANOVA showed significant variation in the mean peak peristaltic pressure value across sites ( < 0.0001) as well as within the data at each site ( < 0.0001). Similarly, the pharyngeal contractile integral exhibited significant inter- ( = 0.003) and intrasubject ( < 0.001) variability. The Shapiro-Wilk normality test showed mixed results, in that some sites showed normally distributed data, whereas others did not. A robust Monte Carlo simulation showed that the nominal sample size was different for various tested metrics. For a power of 0.8, commonly accepted as an adequate threshold for acceptable statistical power, the optimal sample size for various peristaltic parameters ranged between 3 and 15. There is significant intra- and intersubject variability in site-specific and integrated parameters of pharyngeal peristalsis. The observed variance indicates a significant operational range and reserve in pharyngeal contractile function while necessitating parameter-specific sample size for reliable results. Intra- and intersubject variability are significant and different at various sites within the contractile pharynx. In addition, significant swallow-to-swallow and subject-to-subject variability exists in pharyngeal contractile integral. The range of intrasubject variability indicates the existence of broad operational range and reserve. Lastly, our variability studies informed Monte Carlo and power analyses, yielding estimates of sample size that would ensure accurate representation of pressure metric variability.
[Mh] Términos MeSH primario: Deglución/fisiología
Manometría/métodos
Contracción Muscular/fisiología
Peristaltismo/fisiología
Músculos Faríngeos/fisiología
Faringe/fisiología
[Mh] Términos MeSH secundario: Femenino
Humanos
Masculino
Mediana Edad
Presión
Reproducibilidad de Resultados
Sensibilidad y Especificidad
[Pt] Tipo de publicación:JOURNAL ARTICLE
[Em] Mes de ingreso:1708
[Cu] Fecha actualización por clase:170818
[Lr] Fecha última revisión:170818
[Sb] Subgrupo de revista:IM
[Da] Fecha de ingreso para procesamiento:170303
[St] Status:MEDLINE
[do] DOI:10.1152/ajpgi.00382.2016



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