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1.
Infect Immun ; 88(12)2020 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-32900817

RESUMEN

Gastroesophageal reflux is a common gastrointestinal issue that can lead to aspiration and contribute to respiratory problems. Little is known about how reflux can alter the respiratory microenvironment. We aimed to determine if the presence of gastric pepsinogen in the trachea was associated with changes in the microbial and inflammatory microenvironment. A pediatric cohort at high risk of reflux aspiration was prospectively recruited, and the tracheal microenvironment was examined. Pepsinogen A3 (PGA3) and cytokines were measured. The microbiome (bacterial and fungal) was profiled using 16S rRNA and internal transcribed spacer 2 (ITS2) amplicon sequencing. Increased bacterial richness and an altered composition driven by an enrichment of Prevotella correlated with high PGA3 levels. Fungal richness increased with PGA3, with higher Candida relative abundances observed in a subset of samples with high PGA3 levels. Source tracking of tracheal microbial taxa against taxa from matched oral and gastric samples revealed a significantly greater contribution of oral than of gastric taxa with higher PGA3 levels. Tracheal cytokines were differentially produced when stratified according to PGA3, with higher levels of interleukin-1 (IL-1)-related cytokines and IL-8 being associated with high PGA3 levels. Network analysis across cytokine and microbiome measures identified relationships between IL-1-related proteins and microbial taxa, with the presence of respiratory issues associated with higher levels of IL-1ß, IP-10, and Prevotella In conclusion, PGA3 levels in the trachea are correlated with increases in specific microbial taxa and inflammatory molecules, with an increase in oral microbes with increasing PGA3.


Asunto(s)
Citocinas/metabolismo , Reflujo Gastroesofágico/metabolismo , Microbioma Gastrointestinal/genética , Pepsinógeno A/metabolismo , Aspiración Respiratoria/metabolismo , Tráquea/metabolismo , Adolescente , Candida/aislamiento & purificación , Quimiocina CXCL10/metabolismo , Niño , Preescolar , Estudios de Cohortes , Femenino , Reflujo Gastroesofágico/enzimología , Reflujo Gastroesofágico/microbiología , Humanos , Lactante , Inflamación/metabolismo , Inflamación/microbiología , Interleucina-1/metabolismo , Interleucina-1beta/metabolismo , Interleucina-8/metabolismo , Masculino , Prevotella/aislamiento & purificación , ARN Ribosómico 16S/genética , Aspiración Respiratoria/microbiología , Tráquea/enzimología , Tráquea/microbiología
2.
Cir Cir ; 87(4): 436-442, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31264989

RESUMEN

BACKGROUND: Gastroesophageal reflux disease develops when the stomach contents causes troublesome symptoms and complications. Mild forms are non-erosive and erosive esophagitis, and severe forms are Barrett's esophagus and Esophageal adenocarcinoma. Matrix metalloproteinases are endopeptidases that can degrade components of the extracellular matrix, they play an important role in tumor invasion as well as in metastasis. OBJECTIVE: To correlate the expression of metalloproteinase 9 (MMP-9) in esophageal biopsies from patients with mild and severe forms of Gastroesophageal reflux disease. METHOD: Cross-sectional study. The expression of MMP-9 was determined in biopsies of esophageal tissue of patients with mild and severe GRD. The included variables were age, sex, diagnosis, smoking and alcoholic habits, body mass index (BMI) and expression of MMP-9. Descriptive statistics was performed, Kappa for concordance in diagnosis as well as X2. RESULTS: There were 50 patients, 32 (64%) men and 18 (36%) women, mean age 52.13 ± 14.75 years of age. 12 (24%) with smoking and 7 (14%) with alcoholism. Average BMI was 26.71 ± 4.07 kg/m2 (15 to 33); 40 (80%) with obesity. The inter observer concordance for histopathological diagnosis was 1.0 and 0.84 for esophagitis degrees. 27 (54%) patients had esophagitis, 16 (32%) Barrett's esophagus and 7 (14%) esophageal cancer. There was expression of MMP-9 in four patients with esophagitis, five with Barrett's esophagus and five with esophageal cancer. Statistical significance was found between the expression of MMP-9 and smoking (p = 0.011) and histopathological diagnosis (p = 0.052). CONCLUSIONS: The expression of MMP-9 is most common in severe forms compared to the mild forms of GRD.


ANTECEDENTES: La enfermedad por reflujo gastroesofágico (ERGE) se desarrolla cuando el contenido estomacal ocasiona síntomas molestos o complicaciones. Las formas leves son esofagitis no erosiva y erosiva; las graves, esófago de Barrett y adenocarcinoma esofágico. Las metaloproteinasas de la matriz degradan componentes de la matriz extracelular, y tienen un papel importante en la invasión tumoral y la metástasis. OBJETIVO: Relacionar la expresión de la metaloproteinasa-9 (MMP-9) en biopsias esofágicas de pacientes con formas leves y graves de ERGE. MÉTODO: Estudio transversal. Se determinó la expresión de MMP-9 en biopsias esofágicas de pacientes con ERGE grave y leve. Las variables fueron edad, sexo, diagnóstico, tabaquismo, alcoholismo, índice de masa corporal (IMC) y expresión de MMP-9. Se realizó estadística descriptiva, concordancia para el diagnóstico y prueba de ji al cuadrado. RESULTADOS: 50 pacientes, 32 (64%) hombres y 18 (36%) mujeres, con edad media de 52.13 ± 14.75 años. Doce (24%) fumadores y 7 (14%) con alcoholismo. El IMC promedio fue de 26.71 ± 4.07 kg/m2 (rango: 15-33); 40 (80%) eran obesos. La concordancia entre observadores para el diagnóstico histopatológico fue de 1.0, y de 0.84 para esofagitis. Veintisiete (54%) tuvieron esofagitis, 16 (32%) esófago de Barrett y 7 (14%) cáncer de esófago. Hubo expresión de MMP-9 en cuatro pacientes con esofagitis, cinco con esófago de Barrett y cinco con cáncer esofágico. Encontramos diferencia estadísticamente significativa entre la expresión de MMP-9 y el tabaquismo (p = 0.011) y el diagnóstico histopatológico (p = 0.052). CONCLUSIONES: La expresión de MMP-9 es más frecuente en las formas graves que en las leves de ERGE.


Asunto(s)
Esófago/enzimología , Reflujo Gastroesofágico/enzimología , Metaloproteinasa 9 de la Matriz/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Esófago de Barrett/enzimología , Esófago de Barrett/etiología , Índice de Masa Corporal , Distribución de Chi-Cuadrado , Estudios Transversales , Neoplasias Esofágicas/enzimología , Neoplasias Esofágicas/etiología , Esofagitis/enzimología , Esofagitis/etiología , Femenino , Reflujo Gastroesofágico/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Sensibilidad y Especificidad , Fumar/metabolismo , Adulto Joven
3.
Gastroenterology ; 156(5): 1404-1415, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30578782

RESUMEN

BACKGROUND & AIMS: African American and European American individuals have a similar prevalence of gastroesophageal reflux disease (GERD), yet esophageal adenocarcinoma (EAC) disproportionately affects European American individuals. We investigated whether the esophageal squamous mucosa of African American individuals has features that protect against GERD-induced damage, compared with European American individuals. METHODS: We performed transcriptional profile analysis of esophageal squamous mucosa tissues from 20 African American and 20 European American individuals (24 with no disease and 16 with Barrett's esophagus and/or EAC). We confirmed our findings in a cohort of 56 patients and analyzed DNA samples from patients to identify associated variants. Observations were validated using matched genomic sequence and expression data from lymphoblasts from the 1000 Genomes Project. A panel of esophageal samples from African American and European American subjects was used to confirm allele-related differences in protein levels. The esophageal squamous-derived cell line Het-1A and a rat esophagogastroduodenal anastomosis model for reflux-generated esophageal damage were used to investigate the effects of the DNA-damaging agent cumene-hydroperoxide (cum-OOH) and a chemopreventive cranberry proanthocyanidin (C-PAC) extract, respectively, on levels of protein and messenger RNA (mRNA). RESULTS: We found significantly higher levels of glutathione S-transferase theta 2 (GSTT2) mRNA in squamous mucosa from African American compared with European American individuals and associated these with variants within the GSTT2 locus in African American individuals. We confirmed that 2 previously identified genomic variants at the GSTT2 locus, a 37-kb deletion and a 17-bp promoter duplication, reduce expression of GSTT2 in tissues from European American individuals. The nonduplicated 17-bp promoter was more common in tissue samples from populations of African descendant. GSTT2 protected Het-1A esophageal squamous cells from cum-OOH-induced DNA damage. Addition of C-PAC increased GSTT2 expression in Het-1A cells incubated with cum-OOH and in rats with reflux-induced esophageal damage. C-PAC also reduced levels of DNA damage in reflux-exposed rat esophagi, as observed by reduced levels of phospho-H2A histone family member X. CONCLUSIONS: We found GSTT2 to protect esophageal squamous cells against DNA damage from genotoxic stress and that GSTT2 expression can be induced by C-PAC. Increased levels of GSTT2 in esophageal tissues of African American individuals might protect them from GERD-induced damage and contribute to the low incidence of EAC in this population.


Asunto(s)
Adenocarcinoma/genética , Esófago de Barrett/genética , Negro o Afroamericano/genética , Daño del ADN , Mucosa Esofágica/enzimología , Neoplasias Esofágicas/genética , Reflujo Gastroesofágico/genética , Glutatión Transferasa/genética , Población Blanca/genética , Adenocarcinoma/enzimología , Adenocarcinoma/etnología , Adenocarcinoma/patología , Animales , Esófago de Barrett/enzimología , Esófago de Barrett/etnología , Esófago de Barrett/patología , Modelos Animales de Enfermedad , Mucosa Esofágica/patología , Neoplasias Esofágicas/enzimología , Neoplasias Esofágicas/etnología , Neoplasias Esofágicas/patología , Femenino , Reflujo Gastroesofágico/enzimología , Reflujo Gastroesofágico/etnología , Reflujo Gastroesofágico/patología , Glutatión Transferasa/metabolismo , Células HeLa , Histonas/metabolismo , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Fosfoproteínas/metabolismo , Fosforilación , Factores Protectores , Ratas Sprague-Dawley , Factores de Riesgo , Estados Unidos/epidemiología , Regulación hacia Arriba
5.
Medicine (Baltimore) ; 97(39): e12574, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30278564

RESUMEN

BACKGROUND AND AIM: Vonoprazan, a novel potassium-competitive acid blocking agent, is used in the management of gastroesophageal reflux disease (GERD). We aim to perform a systematic review and meta-analysis for the comparison of the effects of vonoprazan and proton pump inhibitors (PPIs) in GERD in randomized controlled trials (RCTs). METHODS: A systematic and comprehensive search will be performed using MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), Google Scholar, and clinical trial registries, for studies published up to September 2018. Only randomized clinical trials will be included. Primary outcomes of symptoms and esophageal erosion improvement in the intention-to-treat analysis, and secondary outcomes of symptoms and esophageal erosion improvement rate in the per protocol analysis, the comparative efficacy in terms of healing rate of esophageal erosion on endoscopy, the comparative efficacy in terms of improvement of esophageal impedance-pH study, adverse events, long-term safety, and the comparative efficacy in terms of CYP2C19 metabolite levels will be studied. The quality of included studies will be assessed using the modified risk of bias tool. Heterogeneity of estimates across studies as well as publication bias will be assessed. This systematic review and meta-analysis will be performed according to the protocol recommended by the Cochrane Collaboration and reported according to the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines. All statistical analyses will be conducted using Stata SE version 15.0. RESULTS: The results of this systematic review and meta-analysis will be published in a peer-reviewed journal. CONCLUSION: To our knowledge, this systematic review and meta-analysis will be the first to evaluate existing research comparing Vonoprazan and PPIs in GERD. Our study will provide information about the effect of vonoprazan and PPIs in GERD in RCTs. The review will benefit patients, healthcare providers, and policymakers.


Asunto(s)
Reflujo Gastroesofágico/tratamiento farmacológico , Inhibidores de la Bomba de Protones/uso terapéutico , Pirroles/uso terapéutico , Sulfonamidas/uso terapéutico , Citocromo P-450 CYP2C19/sangre , Esófago/patología , Reflujo Gastroesofágico/enzimología , Reflujo Gastroesofágico/patología , Humanos , Inhibidores de la Bomba de Protones/efectos adversos , Pirroles/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Sulfonamidas/efectos adversos , Revisiones Sistemáticas como Asunto
6.
Kulak Burun Bogaz Ihtis Derg ; 26(2): 73-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26890709

RESUMEN

OBJECTIVES: This study aims to investigate the presence and concentration of pepsin/pepsinogen in middle ear fluid and to discuss the potential mechanisms involved in the pathogenesis of this condition. PATIENTS AND METHODS: A total of 33 children (21 boys, 12 girls; mean age 5.7±2.4 years; range 3 to 13 years) diagnosed with otitis media with effusion and scheduled for operation were enrolled into the study. Fluids aspirated from the middle ear were assessed for the presence of pepsinogen and albumin and blood samples were drawn simultaneously for comparison. RESULTS: Mean pepsinogen concentration was statistically significantly higher in middle ear fluids compared with serum samples (262.4 ng/mL [range: 211.7 ng/mL - 301.1 ng/mL] versus 102.6 ng/mL [range: 80.7 ng/mL - 134.5 ng/mL], respectively) (p<0.001). On the other hand, mean albumin concentration was significantly lower (1.1 g/dL [range: 0.01 g/dL - 9.5 g/dL] versus 5.8 g/dL [range: 0.9 - 9.5 g/dL], respectively) (p<0.001). The highest pepsinogen concentration was detected in patients with purulent effusion (275.3 ng/mL). CONCLUSION: Our findings support the theory of gastro-esophageal reflux related pepsinogen transition to the middle ear and indicate that pepsinogen may a reliable biochemical marker for the assessment of gastro-esophageal reflux.


Asunto(s)
Oído Medio/enzimología , Otitis Media con Derrame/enzimología , Pepsinógeno A/análisis , Pruebas de Impedancia Acústica/métodos , Adolescente , Albúminas/análisis , Audiometría de Tonos Puros/métodos , Biomarcadores/análisis , Niño , Preescolar , Femenino , Reflujo Gastroesofágico/enzimología , Humanos , Masculino , Otitis Media con Derrame/sangre , Otitis Media Supurativa/enzimología , Otoscopía/métodos , Pepsina A/análisis , Pepsina A/sangre , Pepsinógeno A/sangre , Albúmina Sérica/análisis
7.
Eur Rev Med Pharmacol Sci ; 20(3): 476-85, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26914122

RESUMEN

OBJECTIVE: Reflux is the principal complication for patients after esophagectomy with gastric reconstruction. The aim of this study was to investigate the effect of the modified Nissen fundoplication after resection of adenocarcinoma from the esophagogastric junction (AEG) on controlling the reflux and the role of duodenogastroesophageal reflux (DGER) and cyclooxygenase-2 (COX-2) expression level in the remnant esophagus. PATIENTS AND METHODS: Sixty patients with AEG were randomly divided into two groups: (i) the conventional anastomosis group and (ii) the anti-reflux anastomosis group. Fifty esophagectomized patients were invited to participate in postoperative follow-up after 6 to 12 months. Among those we had 29 cases in the conventional anastomosis group and 21 in the anti-reflux anastomosis group. We used endoscopy, simultaneous 24 hours esophageal pH and bilirubin monitoring in this study. The COX-2 expression level in the remnant esophagus was detected using real-time PCR. RESULTS: The reflux esophagitis prevalence in anti-reflux anastomosis group was comparable to that in the conventional group (p = 0.154). DeMeester score and fraction time of bilirubin abs >0.14 decreased more intensely in the anti-reflux anastomosis group (p < 0.05). The COX-2 expression level in of anti-reflux anastomosis group was evidently lower than that in the conventional anastomosis group (p = 0.022) while it was meaningfully higher compared to the normal control group (p = 0.046). COX-2 up-regulation as well as high prevalence of esophagitis were observed in simultaneous acid reflux and DGER (p < 0.05). CONCLUSIONS: Although modified fundoplication following resection of AEG did not achieve an optimal effect on controlling reflux, it was very effective in decreasing the reflux. COX-2 expression monitoring can be considered as a possible new way to evaluate the impact of anti-reflux surgery. DGER occurring in acidic environment could develop severe reflux esophagitis and up-regulate the COX-2 expression.


Asunto(s)
Ciclooxigenasa 2/biosíntesis , Reflujo Duodenogástrico/enzimología , Neoplasias Esofágicas/enzimología , Esofagectomía/métodos , Reflujo Gastroesofágico/enzimología , Neoplasias Gástricas/enzimología , Adulto , Anciano , Anastomosis Quirúrgica/métodos , Reflujo Duodenogástrico/cirugía , Neoplasias Esofágicas/cirugía , Unión Esofagogástrica/enzimología , Unión Esofagogástrica/cirugía , Femenino , Fundoplicación/métodos , Reflujo Gastroesofágico/cirugía , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Neoplasias Gástricas/cirugía
8.
Am J Crit Care ; 22(5): 408-11, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23996420

RESUMEN

BACKGROUND: Because reflux of gastric juice into the oropharynx must precede its aspiration into the lungs, it is reasonable to hypothesize that the detection of pepsin (the major gastric enzyme in gastric juice) in oral secretions may provide a relatively noninvasive method of predicting risk for aspiration. OBJECTIVE: To describe the incidence of pepsin in oral and tracheal secretions collected concurrently from a sample of 50 gastric-fed patients undergoing mechanical ventilation. METHODS: An exploratory descriptive design with a convenience sample from 4 medical and surgical intensive care units. An oral secretion and a tracheal secretion were collected concurrently from each patient (yielding a sample of 50 oral and 50 tracheal secretions). The tracheal secretions were obtained via the inline suction system with an attached sputum trap; oral secretions were obtained via a Yankauer suction tip with an attached sputum trap. All specimens were assayed for pepsin by the Western blot method. RESULTS: Oral secretions from 10 patients (20%) and tracheal secretions from 2 patients (4%) were pepsin-positive. Both patients with pepsin-positive tracheal secretions also had pepsin-positive oral secretions. Pepsin was not found in the tracheal secretions from the remaining 8 patients with pepsin-positive oral secretions. CONCLUSIONS: Although reflux of gastric juice into the oropharynx must precede its aspiration into the lungs, individual reflux events do not necessarily lead to aspiration. Thus, it is reasonable that we found pepsin 5 times more often in oral secretions than in tracheal secretions.


Asunto(s)
Nutrición Enteral/efectos adversos , Jugo Gástrico/enzimología , Reflujo Gastroesofágico/enzimología , Orofaringe/metabolismo , Pepsina A/análisis , Tráquea/metabolismo , Adulto , Femenino , Jugo Gástrico/metabolismo , Reflujo Gastroesofágico/diagnóstico , Humanos , Unidades de Cuidados Intensivos , Masculino , Orofaringe/enzimología , Proyectos Piloto , Neumonía por Aspiración/etiología , Neumonía por Aspiración/prevención & control , Respiración Artificial/efectos adversos , Aspiración Respiratoria/fisiopatología , Aspiración Respiratoria/prevención & control , Tráquea/enzimología
9.
J Matern Fetal Neonatal Med ; 26(8): 819-24, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23311720

RESUMEN

OBJECTIVE: To study the relationship between pepsinogen/pepsin in a mouth swab and clinical gastroesophageal reflux (GER) in preterm infants. METHODS: Preterm infants (birth weight ≤ 2000 g) on full enteral feeds were enrolled. Mouth swabs from cheek and below the tongue were collected one, two and three hours after feeding. An enzymatic assay with substrate fluorescein isothiocyanate-casein was used to detect pepsin A and C activities with further confirmation by western blot. Blinded investigators reviewed the infant's medical record to clinically diagnose GER. RESULTS: A total of 101 premature infants were enrolled. Pepsinogen/pepsin was detected in 45/101 (44.5%) infants in at least one sample. A clinical diagnosis of GER was made in 36/101 (35.6%) infants. Mouth swabs were positive in 26/36 (72%) infants with clinical GER and only 19/65 (29%) infants without GER (p < 0.001). Similarly, the levels of pepsinogen/pepsin A and C were higher in the mouth swabs of infants with clinical GER. CONCLUSION: The detection of pepsinogen/pepsin in a mouth swab correlates with clinical GER in premature infants.


Asunto(s)
Reflujo Gastroesofágico/diagnóstico , Enfermedades del Prematuro/diagnóstico , Boca/enzimología , Pepsina A/análisis , Biomarcadores/análisis , Western Blotting , Ingestión de Alimentos , Femenino , Reflujo Gastroesofágico/enzimología , Humanos , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/enzimología , Masculino
10.
World J Gastroenterol ; 18(35): 4866-74, 2012 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-23002358

RESUMEN

AIM: To evaluate the effects of indomethacin [dual cyclooxygenase (COX)-1/COX-2 inhibitor] and 3-(3,4-difluorophenyl)-4-(4-(methylsulfonyl) phenyl)-2-(5H)-furanone (MF-tricyclic) (COX-2 selective inhibitor) in a rat experimental model of Barrett's esophagus and esophageal adenocarcinoma. METHODS: A total of 112 surviving post-surgery rats were randomly divided into three groups: the control group (n = 48), which did not receive any treatment; the indomethacin group (n = 32), which were given 2 mg/kg per day of the COX-1/COX-2 inhibitor; and the MF-tricyclic group (n = 32), which received 10 mg/kg per day of the selective COX-2 inhibitor. Randomly selected rats were killed either 8 wk or 16 wk after surgery. The timing of the deaths was in accordance with a previous study performed in our group. Only rats that were killed at the times designated by the protocol were included in the study. We then assessed the histology and prostaglandin E2 (PGE2) expression levels in the rat esophagi. An additional group of eight animals that did not undergo esophagojejunostomy were included in order to obtain normal esophageal tissue as a control. RESULTS: Compared to a control group with no treatment (vehicle-treated rats), indomethacin treatment was associated with decreases in ulcerated esophageal mucosa (16% vs 35% and 14% vs 17%, 2 mo and 4 mo after surgery, respectively; P = 0.021), length of intestinal metaplasia in continuity with anastomosis (2 ± 1.17 mm vs 2.29 ± 0.75 mm and 1.25 ± 0.42 mm vs 3.5 ± 1.54 mm, 2 mo and 4 mo after surgery, respectively; P = 0.007), presence of intestinal metaplasia beyond anastomosis (20% vs 71.4% and 0% vs 60%, 2 mo and 4 mo after surgery, respectively; P = 0.009), severity of dysplasia (0% vs 71.4% and 20% vs 85.7% high-grade dysplasia, 2 mo and 4 mo after surgery, respectively; P = 0.002), and adenocarcinoma incidence (0% vs 57.1% and 0% vs 60%, 2 mo and 4 mo after surgery, respectively; P < 0.0001). Treatment with the selective COX-2 inhibitor, MF-tricyclic, did not prevent development of intestinal metaplasia or adenocarcinoma. In parallel, we observed a significant decrease in PGE2 levels in indomethacin-treated rats, but not in those treated with MF-tricyclic, at both 2 mo and 4 mo. Compared to control rats that did not undergo surgery (68 ± 8 ng/g, P = 0.0022 Kruskal-Wallis test) there was a significant increase in PGE2 levels in the esophageal tissue of the rats that underwent surgery either 2 mo (1332 ± 656 ng/g) or 4 mo (1121 ± 1015 ng/g) after esophagojejunostomy. However, no differences were found when esophageal PGE2 levels were compared 2 mo vs 4 mo post-esophagojejunostomy. At both the 2- and 4-mo timepoints, we observed a significant decrease in PGE2 levels in indomethacin-treated rat esophagi compared to those in either the control or MF-tricyclic groups (P = 0.049 and P = 0.017, respectively). No differences in PGE2 levels were found when we compared levels in rats treated with MF-tricyclic to not-treated rats. CONCLUSION: In this rat model of gastrointestinal reflux, indomethacin was associated with a decrease in the severity of esophagitis and reduced development of esophageal intestinal metaplasia and adenocarcinoma.


Asunto(s)
Adenocarcinoma/prevención & control , Anticarcinógenos/farmacología , Esófago de Barrett/prevención & control , Transformación Celular Neoplásica/efectos de los fármacos , Inhibidores de la Ciclooxigenasa/farmacología , Neoplasias Esofágicas/prevención & control , Esófago/efectos de los fármacos , Reflujo Gastroesofágico/tratamiento farmacológico , Indometacina/farmacología , Proteínas de la Membrana/antagonistas & inhibidores , Adenocarcinoma/enzimología , Adenocarcinoma/patología , Animales , Anticarcinógenos/sangre , Esófago de Barrett/enzimología , Esófago de Barrett/patología , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/metabolismo , Inhibidores de la Ciclooxigenasa 2/farmacología , Inhibidores de la Ciclooxigenasa/sangre , Dinoprostona/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Neoplasias Esofágicas/enzimología , Neoplasias Esofágicas/patología , Esofagitis/enzimología , Esofagitis/patología , Esofagitis/prevención & control , Esófago/enzimología , Esófago/patología , Esófago/cirugía , Femenino , Furanos/farmacología , Reflujo Gastroesofágico/enzimología , Reflujo Gastroesofágico/patología , Indometacina/sangre , Proteínas de la Membrana/metabolismo , Metaplasia , Membrana Mucosa/efectos de los fármacos , Membrana Mucosa/enzimología , Membrana Mucosa/patología , Ratas , Ratas Wistar , Factores de Tiempo
11.
Ther Drug Monit ; 34(3): 242-4, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22495426

RESUMEN

This case report highlights a very rare adverse drug reaction caused by oral pantoprazole resulting in acute pancreatitis. An 11-year-old boy was diagnosed with gastroesophageal reflux disease. Apart from general advice for lifestyle and dietary changes, he was symptomatically prescribed oral pantoprazole 40 mg once daily 30 minutes before meals for 4 weeks. The symptoms of gastroesophageal reflux disease were improving gradually, but the patient developed progressive symptoms of acute pancreatitis and was admitted in the emergency department with acute abdominal pain. Relevant investigations were done, and it was diagnosed as a case of acute pancreatitis. There was no evidence of any other possible hereditary, traumatic, surgical, metabolic, infective, organic, or pathologic causes giving rise to this condition, and this acute pancreatitis was probably drug (pantoprazole) induced. Dechallenge was done, and the patient was treated conservatively resulting in reversal of the diseased state. Naranjo adverse drug reaction probability scale suggested that the likelihood that oral administration of pantoprazole was responsible for the acute pancreatitis was 'probable.'


Asunto(s)
2-Piridinilmetilsulfinilbencimidazoles/administración & dosificación , 2-Piridinilmetilsulfinilbencimidazoles/efectos adversos , Pancreatitis/inducido químicamente , Pancreatitis/diagnóstico , Administración Oral , Niño , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/tratamiento farmacológico , Reflujo Gastroesofágico/enzimología , Humanos , Masculino , Pancreatitis/enzimología , Pantoprazol , Inhibidores de la Bomba de Protones
12.
Int J Cancer ; 131(11): 2478-86, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22422400

RESUMEN

The matrix metalloproteinase (MMP) family of proteins mediates various cellular pathways, including apoptosis and angiogenesis. Polymorphisms of MMP genes are associated with increased esophageal adenocarcinoma (EAC) risk. Gastroesophageal reflux disease (GERD) is an established EAC risk factor. We examined whether MMP polymorphism-EAC risk is modified by GERD. In total, 309 EAC patients and 279 frequency-matched healthy controls underwent MMP1 1G/2G, MMP3 6A/5A, MMP12 -82A/G and MMP12 1082A/G genotyping. Questionnaires collected GERD history. EAC risk was analyzed using logistic regression, adjusted for key covariates and stratified by GERD. Joint effects models explored GERD severity and duration, whereas additional models explored genotype-GERD interactions in EAC risk. We determined that each MMP1 and MMP3 minor (variant) allele was independently associated with increased EAC risk (adjusted odds ratio (AOR) 3.2, 95% confidence interval (CI) 2.0-5.1, p < 0.001 and AOR 1.8, 95% CI 1.1-2.7, p = 0.01, respectively) only among those with GERD but not in GERD-free individuals (all p = nonsignificant). There were significant interactions between the MMP1 variants and the presence of GERD (p = 0.002) and between MMP3 variants and GERD (p = 0.04). There was an equally strong interaction between cumulative GERD severity and MMP1 (p = 0.002). The AOR of each variant allele was 14.9 (95% CI 1.6-136) for individuals with severe GERD, 1.7 (95% CI 1.0-2.7) for mild-moderate GERD and 0.98 (95% CI 0.7-1.4) for those without GERD. This was further reflected in separate analyses of frequency and duration of GERD. In conclusion, MMP1 1G/2G (and possibly MMP3 6A/5A) polymorphisms alter EAC risk differentially for GERD and GERD-free individuals.


Asunto(s)
Adenocarcinoma/enzimología , Adenocarcinoma/genética , Neoplasias Esofágicas/enzimología , Neoplasias Esofágicas/genética , Reflujo Gastroesofágico/enzimología , Reflujo Gastroesofágico/genética , Metaloproteinasas de la Matriz/genética , Anciano , Alelos , Intervalos de Confianza , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Factores de Riesgo
13.
Int J Surg ; 10(2): 73-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22197650

RESUMEN

BACKGROUND: Investigations of molecular mechanisms behind the progression of neoplastic changes in the esophagus have uncovered the role of the COX & 5-Lox pathways. Human squamous esophageal mucosa produces relatively large amounts of eicosanoids in the presence of inflammation. Laboratory and epidemiological data suggest that aspirin and non-steroidal anti-inflammatory drugs may be chemo preventive through their inhibitory effect on COX25, 10. Cell culture studies have shown that the members of the mitogen activated protein (MAP) kinase family plays an important role in the development of bile acid-induced carcinogenesis. Differences in MAPK pathways activated by bile exposure were also noted in esophageal squamous cell lines and biopsies from patients with GERD. The protective role of aspirin and its molecular mechanism is not well understood. AIMS: 1. The effect of duodenal reflux on esophageal mucosa. 2. The role of aspirin in preventing duodenal reflux induced esophageal mucosa changes. 3. If it is proven to be preventive, the mechanism of its action. A duodenal reflux rat animal model was used by an end- to-side esophago duodenostomy. METHODS: Total of 56 rats was included. 3 were "Naive control" animals which did not undergo the surgical procedure. The remaining animals were divided into two groups: Surgery alone (experimental) and Surgery + aspirin [therapy group], esophagoduodenostomy. At 40 weeks, the rats were euthanized and appropriate esophageal samples were analysed for histopathology and p38 & ERK MAP kinases, VEGF, protease activity and caspase 3 activities. RESULTS: The presence of gross mucosal nodularity was seen in 21 and 10 rats of the experimental and therapy group respectively (p = 0.03; Table 1). Reflux-associated changes such as basal cell hyperplasia were more common in the experimental group, however this association did not reach statistical significance (p = 0.15; Table 1). Epithelial hyperplasia was seen more in the experimental group, which was prevented by aspirin [p < 0.01]. Papillomatosis, as shown in Fig. 4 was more common in the experimental group (p = 0.02). Activation of p38 & ERK MAP kinases was prevented in aspirin group (p < 0.05, CI -1.796--0.014). Examination of protease activity by zymographic analysis of the esophageal samples revealed a number of gelatinolytic bands in 50% rats of the experimental group, not observed in the therapy group. No significant changes were seen in Caspase 3 [Normal areas -99.74 & nodular areas - 100.34 percent of controls] or VEGF [mean 0.64, sd ± 0.76 Vs 0.69 ± 0.96] activity. CONCLUSIONS: Our data demonstrated that low dose aspirin reduced the incidence of duodenoesophageal reflux induced histological changes in the esophagus by preventing activation of proliferative & anti-apoptotic MAP kinases such as p38 & ER as well as protease activity. Though Barretts' changes and adenocarcinoma have not developed, it could explain the role of duodenoesophageal reflux in the development of different histological but potential premalignant lesions and molecular level changes which are prevented by low dose aspirin.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Aspirina/uso terapéutico , Neoplasias Esofágicas/prevención & control , Reflujo Gastroesofágico/patología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Animales , Antiinflamatorios no Esteroideos/farmacología , Aspirina/farmacología , Biomarcadores/metabolismo , Western Blotting , Caspasa 3/metabolismo , Relación Dosis-Respuesta a Droga , Neoplasias Esofágicas/enzimología , Reflujo Gastroesofágico/enzimología , Ratas , Ratas Wistar , Resultado del Tratamiento
14.
J Pharm Pharmacol ; 63(12): 1572-80, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22060288

RESUMEN

OBJECTIVES: Cyclooxygenase(COX)-2 is implicated in variety of pathophysiological processes, although its role in acute reflux oesophagitis is debatable. This study was designed to evaluate the role of COX-2 during oesophagitis and in melatonin-elicited protection in rats. METHODS: Reflux oesophagitis was induced in rats by ligating the pyloric end and the limiting ridge of the stomach for 5 h. Celecoxib (COX-2 blocker; 10 mg/kg), 16,16-dimethyl prostaglandinE(2) (dmPGE(2); a synthetic analogue of PGE(2) ; 10 µg/kg), melatonin (20 and 40 mg/kg) and omeprazole (10 mg/kg) were given intra-peritoneally 45 min before induction of oesophagitis in rats. Alterations in COX-1 and 2 gene expression and protein levels level were analysed via RT-PCR and Western blotting, respectively. Mucosal PGE(2) level and myeloperoxidase (MPO) activity were measured using an enzyme immunoassay (EIA) kit and spectrophotometrically, respectively. KEY FINDINGS: COX-2 over-expression during reflux oesophagitis promotes inflammation of the oesophagus as celecoxib pretreatment significantly reduced tissue damage and MPO activity in rats with reflux oesophagitis (RE-rats). By contrast, dmPGE(2) pretreatment significantly exacerbated tissue injury and simultaneously increased COX-2 expression, PGE(2) levels and MPO activity in RE-rats. Further, melatonin pretreatment significantly reduced the tissue injury, COX-2 over-expression, PGE(2) level and MPO activity in RE-rats. Melatonin offered more potent suppression of COX-2, PGE(2) and MPO activity than the proton-pump inhibitor omeprazole; however, both reduced the lesion injury to a similar extent. Melatonin at a dose of 20 mg/kg failed to inhibit significantly the dmPGE(2) -induced tissue damage, COX-2 expression, PGE(2) level and MPO activity in RE-rats while at a higher dose of 40 mg/kg it significantly attenuated these changes. CONCLUSION: Our results suggest that COX-2 plays an important pro-inflammatory role during acute reflux oesophagitis in rats and its inhibition contributes significantly to melatonin-exerted protection against reflux oesophagitis.


Asunto(s)
Antioxidantes/uso terapéutico , Ciclooxigenasa 2/metabolismo , Esofagitis/enzimología , Reflujo Gastroesofágico/enzimología , Reflujo Gastroesofágico/prevención & control , Melatonina/uso terapéutico , Animales , Western Blotting , Ciclooxigenasa 1/biosíntesis , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/biosíntesis , Dinoprostona/biosíntesis , Activación Enzimática/efectos de los fármacos , Esófago/patología , Hemorragia Gastrointestinal/enzimología , Hemorragia Gastrointestinal/patología , Regulación Enzimológica de la Expresión Génica/genética , Regulación Enzimológica de la Expresión Génica/fisiología , Técnicas para Inmunoenzimas , Membrana Mucosa/patología , Peroxidasa/metabolismo , Reacción en Cadena de la Polimerasa , Ratas , Ratas Sprague-Dawley
15.
Pharmacogenomics ; 12(6): 873-88, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21692617

RESUMEN

Proton pump inhibitors (PPIs) are widely used for the treatment of gastroesophageal reflux disease as well as other acid-related disorders. PPIs are metabolized primarily via the CYP2C19 and CYP3A4 isoenzymes; their activity is influenced both by exogenous and endogenous (pharmacogenetic) factors. The CYP2C19 polymorphism affects the metabolism of PPIs, causing large individual pharmacokinetic variations. Differences in the CYP2C19-mediated metabolism can produce marked interpatient variability in acid suppression, in drug-interaction potential and in clinical efficacy. Understanding the pharmacokinetic properties of PPIs and examining the pharmacogenetic alterations may help clinicians optimize PPI therapy and administer individual treatment, especially to nonresponder patients with gastroesophageal reflux disease or ulcer or after failed eradication therapy.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas/genética , Reflujo Gastroesofágico/tratamiento farmacológico , Reflujo Gastroesofágico/genética , Inhibidores de la Bomba de Protones/farmacocinética , Hidrocarburo de Aril Hidroxilasas/metabolismo , Citocromo P-450 CYP2C19 , Interacciones Farmacológicas , Reflujo Gastroesofágico/enzimología , Humanos , Farmacogenética , Polimorfismo Genético
16.
Am J Gastroenterol ; 106(2): 264-71, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20978486

RESUMEN

OBJECTIVES: Mast cells may contribute to the pathogenesis of eosinophilic esophagitis (EoE), but their role in diagnosis is unknown. Our aim was to determine whether tryptase staining of esophageal mast cells differentiates EoE from gastroesophageal reflux disease (GERD) and has utility for diagnosis of EoE. METHODS: We performed a case-control study comparing patients with EoE, defined by consensus guidelines, to GERD patients with eosinophils on esophageal biopsy. Immunohistochemistry was performed with mast cell tryptase. The density (mast cells/mm2) and intensity (0-4 scale) of mast cell staining was compared between groups after masking the diagnosis. Receiver operating characteristic (ROC) curves were constructed, and the area under the curve (AUC) was calculated to assess mast cell staining as both a stand-alone diagnostic test and an adjunctive assay with eosinophil counts. RESULTS: Fifty-four EoE (mean age 24 years; 69% male; mean 146 eosinophils per high-power field (eos/hpf)) and 55 GERD (mean age 34 years; 60% male; mean 20 eos/hpf) patients were analyzed. The maximum epithelial tryptase density was higher in EoE than in GERD (162±87 mast cells/mm2 vs. 67±54; P<0.001). Mast cells were diffusely distributed throughout the biopsy in more EoE than GERD patients (41 vs. 7%; P<0.001). Tryptase density and eosinophil count were only weakly correlated (R2=0.09; P=0.002). The AUC was 0.84 for tryptase staining alone, and 0.96 for the combination of mast cells and eosinophils. CONCLUSIONS: Patients with EoE have higher levels of tryptase-positive mast cells compared with GERD patients, improving the diagnostic value of biopsies beyond eosinophil counts alone. Mast cell tryptase may have utility as a diagnostic assay for EoE.


Asunto(s)
Esofagitis Eosinofílica/diagnóstico , Esofagitis Eosinofílica/enzimología , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/enzimología , Mastocitos/enzimología , Triptasas/metabolismo , Adulto , Área Bajo la Curva , Biopsia , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Femenino , Humanos , Inmunohistoquímica , Masculino , Curva ROC
17.
Eksp Klin Gastroenterol ; (6): 19-23, 2010.
Artículo en Ruso | MEDLINE | ID: mdl-20731160

RESUMEN

UNLABELLED: AIM. To study features of lipids peroxide oxidation and function of antioxidant protection in patients with various variants of gastro-esophageal reflux disease (GERD). MATERIAL AND METHODS: 120 patients with GERD and 20 healthy persons were examinated. Diene conjugates, ketodienes, connected trienes, concentration of intermediants of peroxide oxidation, catalase activity and general antioxidizing activity index were investigated in blood serum and esophageal biopsy specimens by biochemical methods. RESULTS: The level of peroxide oxidation products in esophageal biopsy specimens in esophagitis and complicated GERD was 1.8-4.5 times higher then in control group. The level of catalase activity and general antioxidizing activity was 2-5 times lower in patients with the pathology in comparison to healthy persons. CONCLUSION: Patients with GERD had activation of lipids peroxide oxidation accompanied by deficiency of antioxidants in esophageal mucosa and blood serum proportionally to esophagus damage degree.


Asunto(s)
Antioxidantes/metabolismo , Esofagitis/metabolismo , Reflujo Gastroesofágico/metabolismo , Peroxidación de Lípido , Adulto , Estudios de Casos y Controles , Catalasa/sangre , Catalasa/metabolismo , Esofagitis/sangre , Esofagitis/enzimología , Esofagitis/patología , Esofagoscopía , Esófago/enzimología , Esófago/metabolismo , Esófago/patología , Reflujo Gastroesofágico/sangre , Reflujo Gastroesofágico/enzimología , Reflujo Gastroesofágico/patología , Humanos , Peróxidos Lipídicos/sangre , Peróxidos Lipídicos/metabolismo , Persona de Mediana Edad
18.
Chest ; 138(4): 937-43, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20522573

RESUMEN

BACKGROUND: Lung transplantation is associated with a high incidence of gastroesophageal reflux disease (GERD). The presence of GERD is considered a risk factor for the subsequent development of obliterative bronchiolitis (OB), and surgical correction of GERD by gastric fundoplication (GF) may be associated with increased freedom from OB. The mechanisms underlying a protective effect from OB remain elusive. The objective of this study was to analyze the flow cytometric properties of BAL cells in patients who have undergone GF early after transplant. METHODS: In a single-center lung transplant center, eight patients with GERD who were in the first transplant year underwent GF. Prior to and immediately following GF, BAL cells were analyzed by polychromatic flow cytometry. Spirometry was performed before and after GF. RESULTS: GF was associated with a significant reduction in the frequency of BAL CD8 lymphocytes expressing the intracellular effector marker granzyme B, compared with the pre-GF levels. Twenty-six percent of CD8 cells were granzyme Bhi pre-GF compared with 12% of CD8 cells post-GF (range 8%-50% pre-GF, 2%-24% post-GF, P = .01). In contrast, GF was associated with a significant interval increase in the frequency of CD8 cells with an exhausted phenotype (granzyme Blo, CD127lo, PD1hi) from 12% of CD8 cells pre-GF to 24% post-GF (range 1.7%-24% pre-GF and 11%-47% post-GF, P = .05). No significant changes in spirometry were observed during the study interval. CONCLUSIONS: Surgical correction of GF is associated with a decreased frequency of potentially injurious effector CD8 cells in the BAL of lung transplant recipients.


Asunto(s)
Líquido del Lavado Bronquioalveolar/citología , Linfocitos T CD8-positivos/inmunología , Reflujo Gastroesofágico/inmunología , Reflujo Gastroesofágico/cirugía , Trasplante de Pulmón/inmunología , Complicaciones Posoperatorias/inmunología , Biomarcadores/análisis , Femenino , Citometría de Flujo , Reflujo Gastroesofágico/enzimología , Granzimas/análisis , Humanos , Masculino , Persona de Mediana Edad , Espirometría
19.
Eksp Klin Gastroenterol ; (2): 53-8, 2010.
Artículo en Ruso | MEDLINE | ID: mdl-20496811

RESUMEN

Proton pump inhibitors (PPI) are most effective for the gastroesophageal reflux disease (GERD) treatment. The effectiveness of PPI in the long-term treatment of GERD is similar. However, the PPI are different according to fast onset and duration of antisecretory action, pH-selectivity, metabolism, interactions with other medicines and dosage forms. In some clinical situations, these differences can be significant. In this article was described features of the pharmacokinetics of PPI. It was shown that the early stages of treatment of certain advantages in speed of onset of effect is lansoprazole, which potentially increases the patient's adherence to treatment. Metabolism in the cytochrome P450 system provides the lowest profile of pantoprazole drug interactions, making it the most secure in the presence of GERD in a patient comorbidities and need for drugs used to treat it.


Asunto(s)
2-Piridinilmetilsulfinilbencimidazoles/farmacocinética , 2-Piridinilmetilsulfinilbencimidazoles/uso terapéutico , Reflujo Gastroesofágico/tratamiento farmacológico , Inhibidores de la Bomba de Protones/farmacocinética , Inhibidores de la Bomba de Protones/uso terapéutico , Sistema Enzimático del Citocromo P-450/metabolismo , Interacciones Farmacológicas , Reflujo Gastroesofágico/enzimología , Humanos , Lansoprazol , Factores de Tiempo
20.
Dis Esophagus ; 23(5): 430-6, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20095996

RESUMEN

Exposure of esophageal epithelium to gastric and duodenal contents results in the histologic changes of hyperproliferation and mucosal thickening. We have previously shown that presence of secretory phospholipase A(2) (sPLA(2)) is necessary to produce these histologic changes in a murine model of gastroduodenal reflux. We sought to determine the influence of gastroduodenal reflux (GDR) on sPLA(2) protein and mRNA levels as well as enzyme activity in esophageal tissue. BALB/c (sPLA(2)(+/+)) mice (n= 28) underwent side-to-side surgical anastomosis of the first portion of the duodenum and GE junction (DGEA) resulting in continuous exposure of esophageal mucosa to mixed gastric and duodenal contents. Sham control mice (n= 14) underwent laparotomy, esophagotomy and closure. Real-time RT PCR was used to quantitate the influence of GDR on group IIa sPLA(2) expression. Immunofluorescent staining was quantitated by digital microscopy using a specific antibody to identify and locate sPLA(2) protein. A colorimetric assay was used to quantify total sPLA(2) activity after standardization of protein levels. Statistical analysis was conducted using Student's t-test. Group IIa sPLA(2) mRNA and protein levels were increased at 4 and 8 weeks compared with sham controls. This increase occurred in a time-dependent manner and correlated with esophageal mucosal thickness. Furthermore, sPLA(2) enzyme activity was increased significantly at 4 and 8 weeks compared with untreated controls. The expression of group IIa sPLA(2) as well as sPLA(2) activity is induced by GDR. This novel finding indicates that sPLA(2) may play a role in the development of the histologic changes produced by GDR in esophageal mucosa.


Asunto(s)
Esofagitis Péptica/enzimología , Esófago/enzimología , Reflujo Gastroesofágico/enzimología , Fosfolipasas A2 Grupo II/metabolismo , Animales , Modelos Animales de Enfermedad , Esofagitis Péptica/patología , Esófago/patología , Técnica del Anticuerpo Fluorescente , Reflujo Gastroesofágico/patología , Fosfolipasas A2 Grupo II/genética , Hiperplasia/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Membrana Mucosa/enzimología , Membrana Mucosa/patología , ARN Mensajero , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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