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1.
Aliment Pharmacol Ther ; 38(7): 772-83, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23957603

RESUMO

BACKGROUND: A total of 10-15% of patients with an ileoanal pouch develop severe pouchitis necessitating long-term use of antibiotics or pouch excision. Probiotics reduce the risk of recurrence of pouchitis, but mechanisms behind these effects are not fully understood. AIM: To examine mucosal barrier function in pouchitis, before and after probiotic supplementation and to assess composition of mucosal pouch microbiota. METHODS: Sixteen patients with severe pouchitis underwent endoscopy with biopsies of the pouch on three occasions: during active pouchitis; clinical remission by 4 weeks of antibiotics; after 8 weeks of subsequent probiotic supplementation (Ecologic 825, Winclove, Amsterdam, the Netherlands). Thirteen individuals with a healthy ileoanal pouch were sampled once as controls. Ussing chambers were used to assess transmucosal passage of Escherichia coli K12, permeability to horseradish peroxidase (HRP) and 5¹Cr-EDTA. Composition and diversity of the microbiota was analysed using Human Intestinal Tract Chip. RESULTS: Pouchitis Disease Activity Index (PDAI) was significantly improved after antibiotic and probiotic supplementation. Escherichia coli K12 passage during active pouchitis [3.7 (3.4-8.5); median (IQR)] was significantly higher than in controls [1.7 (1.0-2.4); P < 0.01], did not change after antibiotic treatment [5.0 (3.3-7.1); P = ns], but was significantly reduced after subsequent probiotic supplementation [2.2 (1.7-3.3); P < 0.05]. No significant effects of antibiotics or probiotics were observed on composition of mucosal pouch microbiota; however, E. coli passage correlated with bacterial diversity (r = -0.40; P = 0.018). Microbial groups belonging to Bacteroidetes and Clostridium clusters IX, XI and XIVa were associated with healthy pouches. CONCLUSIONS: Probiotics restored the mucosal barrier to E. coli and HRP in patients with pouchitis, a feasible factor in prevention of recurrence during maintenance treatment. Restored barrier function did not translate into significant changes in mucosal microbiota composition, but bacterial diversity correlated with barrier function.


Assuntos
Colite Ulcerativa/cirurgia , Bolsas Cólicas/microbiologia , Pouchite/tratamento farmacológico , Probióticos/uso terapêutico , Adulto , Idoso , Antibacterianos/uso terapêutico , Biópsia , Bolsas Cólicas/patologia , Escherichia coli , Feminino , Humanos , Mucosa Intestinal/microbiologia , Masculino , Microbiota , Pessoa de Meia-Idade , Permeabilidade , Pouchite/patologia , Recidiva
2.
Neurogastroenterol Motil ; 25(7): 574-8, e457-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23607721

RESUMO

BACKGROUND: Patients with gastroesophageal reflux disease (GERD) have impaired esophageal mucosal integrity. Measurement of the mucosal integrity is complex and time-consuming. Electrical tissue impedance spectroscopy (ETIS) is a device that measures impedance of tissue in vivo during endoscopy. In this study, we aimed to validate ETIS as a measure of esophageal mucosal integrity. METHODS: Electrical tissue impedance spectroscopy measurements were performed during upper endoscopy in 12 GERD patients and 11 healthy controls after cessation of proton pump inhibition. During endoscopy biopsies of the distal esophagus were obtained for transmission electron microscopy to determine dilation of intercellular spaces (DIS) and for Ussing chamber experiments to determine transepithelial permeability and transepithelial electrical resistance. KEY RESULTS: Extracellular impedance measured in vivo by ETIS was significantly lower in GERD patients compared to controls [mean (SD) 5621 (3299) Ω.m and 8834 (2542) Ω.m, respectively, P < 0.05]. We found a strong inverse relation between extracellular impedance determined by ETIS and DIS (r = -0.76, P < 0.05), and between extracellular resistance in vivo and transepithelial permeability of esophageal biopsies (r = -0.65, P < 0.01). CONCLUSIONS & INFERENCES: Electrical tissue impedance spectroscopy is a new tool that can be used to evaluate esophageal mucosal integrity changes during endoscopy.


Assuntos
Técnicas de Diagnóstico do Sistema Digestório , Esôfago/fisiopatologia , Refluxo Gastroesofágico/diagnóstico , Mucosa/fisiopatologia , Adulto , Idoso , Técnicas de Diagnóstico do Sistema Digestório/instrumentação , Espectroscopia Dielétrica , Impedância Elétrica , Endoscopia do Sistema Digestório , Esôfago/ultraestrutura , Feminino , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Mucosa/ultraestrutura , Técnicas de Patch-Clamp , Adulto Jovem
3.
Neurogastroenterol Motil ; 23(2): e57-68, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20964790

RESUMO

BACKGROUND: The parasitized or inflamed gastrointestinal mucosa shows an increase in the number of mucosal mast cells (MMC) and the density of extrinsic primary afferent nerve fibers containing the neuropeptide, calcitonin gene-related peptide (CGRP). Currently, the mode of action of CGRP on MMC is unknown. METHODS: The effects of CGRP on mouse bone marrow-derived mucosal mast cells (BMMC) were investigated by measurements of intracellular Ca(2+)[Ca(2+)](i) and release of mMCP-1. KEY RESULTS: Bone marrow-derived mucosal mast cells responded to the application of CGRP with a single transient rise in [Ca(2+)](i). The proportion of responding cells increased concentration-dependently to a maximum of 19 ± 4% at 10(-5)mol L(-1) (mean ±SEM; C48/80 100%; EC(50)10(-8) mol L(-1) ). Preincubation with the CGRP receptor antagonist BIBN4096BS (10(-5) mol L(-1)) completely inhibited BMMC activation by CGRP [range 10(-5) to 10(-11) mol L(-1); analysis of variance (ANOVA) P < 0.001], while preincubation with LaCl(3) to block Ca(2+) entry did not affect the response (P = 0.18). The presence of the CGRP1 receptor on BMMC was confirmed by simultaneous immunofluorescent detection of RAMP1 or CRLR, the two components of the CGRP1 receptor, and mMCP-1. Application of CGRP for 1 h evoked a concentration-dependent release of mMCP-1 (at EC(50) 10% of content) but not of ß-hexosaminidase and alterations in granular density indicative of piecemeal release. CONCLUSIONS & INFERENCES: We demonstrate that BMMC express functional CGRP1 receptors and that their activation causes mobilization of Ca(2+) from intracellular stores and piecemeal release of mMCP-1. These findings support the hypothesis that the CGRP signaling from afferent nerves to MMC in the gastrointestinal wall is receptor-mediated.


Assuntos
Medula Óssea/metabolismo , Quimases/metabolismo , Mastócitos/metabolismo , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , Animais , Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina , Cálcio/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Masculino , Mastócitos/citologia , Camundongos , Camundongos Endogâmicos BALB C , Piperazinas/farmacologia , Quinazolinas/farmacologia , Transdução de Sinais/fisiologia , beta-N-Acetil-Hexosaminidases/metabolismo
4.
Neurogastroenterol Motil ; 22(6): 646-e179, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20367800

RESUMO

BACKGROUND: Gastrointestinal (GI)-specific anxiety (GSA) has been proposed to influence symptom severity and quality of life (QOL) in patients with irritable bowel syndrome (IBS). The Visceral Sensitivity Index (VSI) is a recently developed, reliable and valid measure of GSA. Our aim was to evaluate the association between GSA, GI symptom severity, and QOL in IBS patients. METHODS: Sixty healthy subjects and 306 patients fulfilling the Rome II criteria for IBS were studied. Demographic and disease-related factors were assessed. Patients completed VSI and GI Symptom Rating Scale (GSRS) and questionnaires to determine psychological symptom severity (Hospital Anxiety and Depression Scale), QOL (Short form 36), and presence of functional GI disorders (Rome II Modular Questionnaire). KEY RESULTS: Compared with healthy subjects, patients with IBS had more severe GSA (34.7 +/- 16.9 vs. 2.2 +/- 4.4 [mean +/- standard deviation]; P < 0.0001). In the IBS group, more severe GSA was seen in patients with more severe GI symptoms (P < 0.0001), general anxiety (P < 0.0001) and depression (P < 0.0001), and with lower socioeconomic status (P < 0.05). In a regression analysis, GSA was the strongest predictor for GI symptom severity (GSRS total score), followed by number of Rome II diagnoses, presence of meal-related IBS symptoms, and gender (R(2) = 0.34). Gastrointestinal-specific anxiety was also, together with general anxiety, depression, socioeconomic status, and gender, found to be independently associated with mental QOL (R(2) = 0.62). CONCLUSIONS & INFERENCES: Gastrointestinal-specific anxiety seems to be an important factor for GI symptom severity and QOL in patients with IBS.


Assuntos
Ansiedade/psicologia , Trato Gastrointestinal/fisiopatologia , Síndrome do Intestino Irritável/fisiopatologia , Síndrome do Intestino Irritável/psicologia , Qualidade de Vida , Adulto , Idoso , Análise de Variância , Ansiedade/etiologia , Interpretação Estatística de Dados , Depressão/etiologia , Depressão/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Análise de Regressão , Inquéritos e Questionários , Adulto Jovem
5.
J Control Release ; 133(2): 161-8, 2009 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-18955093

RESUMO

The purpose of this study was to assess the ability of polymeric micelles to enable gastrointestinal absorption of the extremely hydrophobic compound vitamin K, by comparison of its absorption in bile duct ligated and sham operated rats. Hereto, vitamin K was encapsulated in micelles composed of mPEG(5000)-b-p(HPMAm-lac(2)), a thermosensitive block copolymer. Vitamin K plasma levels rose significantly upon gastric administration of 1 mg vitamin K encapsulated in polymeric micelles in sham operated rats, but not after bile duct ligation (AUC 4543 and 1.64 ng/mL/h respectively, p<0.01). Duodenal administration of polymeric micelles together with bile acids in bile duct ligated rats fully restored absorption. Dynamic light scattering time series showed a significant and dose dependent rise in micellar size in the presence of bile acids in vitro, indicating the gradual formation of mixed micelles during the first 3 h of incubation. The highest bile acid amounts (11 mM deoxycholic acid and 41 mM taurocholic acid) eventually caused aggregation of the loaded micelles after the formation of mixed micelles. These data suggest that the gastrointestinal absorption of encapsulated vitamin K from polymeric micelles is mediated by free bile and that uptake of intact micelles through pinocytosis is insignificant.


Assuntos
Ácidos e Sais Biliares/metabolismo , Micelas , Polímeros/química , Vitamina K/farmacocinética , Administração Oral , Animais , Área Sob a Curva , Ácidos e Sais Biliares/farmacologia , Ductos Biliares/cirurgia , Disponibilidade Biológica , Portadores de Fármacos/química , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Absorção Intestinal/efeitos dos fármacos , Ligadura , Luz , Masculino , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Ratos , Ratos Wistar , Espalhamento de Radiação , Ultrafiltração , Vitamina K/administração & dosagem , Vitamina K/química , Vitaminas/administração & dosagem , Vitaminas/química , Vitaminas/farmacocinética
6.
Ned Tijdschr Geneeskd ; 152(12): 685-96, 2008 Mar 22.
Artigo em Holandês | MEDLINE | ID: mdl-18438065

RESUMO

OBJECTIVE: To evaluate whether enteral prophylaxis with probiotics in patients with predicted severe acute pancreatitis prevents infectious complications. DESIGN: Multicentre, randomised, double-blind, placebo-controlled trial. METHOD: A total of 296 patients with predicted severe acute pancreatitis (APACHE II score > or = 8, Imrie score > or = 3 or C-reactive protein concentration > 150 mg/l) were included and randomised to one of two groups. Within 72 hours after symptom onset, patients received a multispecies preparation of probiotics or placebo given twice daily via a jejunal catheter for 28 days. The primary endpoint was the occurrence of one of the following infections during admission and go-day follow-up: infected pancreatic necrosis, bacteraemia, pneumonia, urosepsis or infected ascites. Secondary endpoints were mortality and adverse reactions. The study registration number is ISRCTN38327949. RESULTS: Treatment groups were similar at baseline with regard to patient characteristics and disease severity. Infections occurred in 30% of patients in the probiotics group (46 of 152 patients) and 28% of those in the placebo group (41 of 144 patients; relative risk (RR): 1.1; 95% CI: 0.8-1.5). The mortality rate was 16% in the probiotics group (24 of 152 patients) and 6% (9 of 144 patients) in the placebo group (RR: 2.5; 95% CI: 1.2-5.3). In the probiotics group, 9 patients developed bowel ischaemia (of whom 8 patients died), compared with none in the placebo group (p = 0.004). CONCLUSION: In patients with predicted severe acute pancreatitis, use of this combination of probiotic strains did not reduce the risk of infections. Probiotic prophylaxis was associated with a more than two-fold increase in mortality and should therefore not be administered in this category of patients.

7.
Neurogastroenterol Motil ; 20(8): 900-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18363639

RESUMO

Colorectal and small intestinal visceral hypersensitivity has been demonstrated in irritable bowel syndrome (IBS). Serine protease signalling via protease-activated receptor (PAR)-2 promotes hyperalgesia to mechanical distension. Furthermore, serotonergic pathways are involved in gastrointestinal visceral sensitivity. Abnormalities of serine protease and serotonergic signalling components have been identified in IBS colorectal mucosal biopsies. We determined the role of altered mucosal serine protease and serotonergic signalling in small intestine of IBS patients. Duodenal mucosal biopsies of 34 IBS patients (10 constipation-,11 diarrhoea-predominant and 13 alternating) and 20 healthy subjects (HS) were collected. Gene transcripts of PAR-2, trypsinogen IV, TPH-1, SERT (serotonin transport protein) and serotonin (5-HT(3)) subunits were quantified using real-time PCR and 5-HT content was measured by ELISA. Irritable bowel syndrome patients showed 1.5-fold higher trypsinogen IV mRNA level compared to HS (P = 0.016). SERT expression was 1.8-fold higher in IBS compared to HS (P = 0.007). Mucosal 5-HT content was 1.7-fold higher in IBS compared to HS (P = 0.015). The increase was 2.1-fold in IBS-C relative to HS (P = 0.018). Transcript levels of PAR-2, TPH-1 and 5-HT(3) receptor subunits did not differ between IBS and HS. In conclusion enhanced trypsinogen IV expression in IBS may cause increased PAR-2 activation. Increased SERT expression and mucosal 5-HT content in IBS suggest higher 5-HT availability. Both may contribute to small intestinal visceral hypersensitivity in IBS patients.


Assuntos
Intestino Delgado/metabolismo , Síndrome do Intestino Irritável/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Serotonina/metabolismo , Tripsina/metabolismo , Adulto , Animais , Feminino , Humanos , Intestino Delgado/anatomia & histologia , Síndrome do Intestino Irritável/fisiopatologia , Masculino , Pessoa de Meia-Idade , Receptor PAR-2/genética , Receptor PAR-2/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Tripsina/genética , Triptofano Hidroxilase/genética , Triptofano Hidroxilase/metabolismo
8.
Lett Appl Microbiol ; 46(1): 61-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17944834

RESUMO

AIMS: Although probiotic prophylaxis has been suggested to prevent small bowel bacterial overgrowth, bacterial translocation and infection of pancreatic necrosis in severe acute pancreatitis, limited data are available on their antimicrobial activity. METHODS AND RESULTS: Using the well-diffusion method, we studied the antimicrobial properties of a multispecies probiotic product (Ecologic 641) against a collection of pathogens cultured from infected pancreatic necrosis. All individual probiotic strains included in the multispecies preparation were able to inhibit the growth of the pathogens to some extent. However, the combination of the individual strains (i.e. the multispecies preparation) was able to inhibit all pathogenic isolates. Probiotic-free supernatants adjusted to pH 7 were not able to inhibit pathogen growth. CONCLUSION: Ecologic 641 is capable of inhibiting growth of a wide variety of pathogens isolated from infected pancreatic necrosis. The antimicrobial properties are to a large extent explained by the production of organic acids. SIGNIFICANCE AND IMPACT OF THE STUDY: Ecologic 641 is currently being used in a Dutch nationwide double-blind, placebo-controlled, randomized multicentre trial in patients with predicted severe acute pancreatitis.


Assuntos
Antibiose , Bactérias/crescimento & desenvolvimento , Pâncreas/microbiologia , Pancreatopatias/microbiologia , Probióticos/farmacologia , Ácidos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Humanos , Concentração de Íons de Hidrogênio , Pâncreas/patologia , Pancreatite Necrosante Aguda/microbiologia , Probióticos/metabolismo
9.
J Gastrointest Surg ; 11(5): 682-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17468930

RESUMO

Infection of pancreatic necrosis with intestinal flora is accepted to be a main predictor of outcome during severe acute pancreatitis. Bacterial translocation is the process whereby luminal bacteria migrate to extraintestinal sites. Animal models were proven indispensable in detecting three major aspects of bacterial translocation: small bowel bacterial overgrowth, mucosal barrier failure, and disturbed immune responses. Despite the progress made in the knowledge of bacterial translocation, the exact mechanism, origin and route of bacteria, and the optimal prophylactic and treatment strategies remain unclear. Methodological restrictions of animal models are likely to be the cause of this uncertainty. A literature review of animal models used to study bacterial translocation during acute pancreatitis demonstrates that many experimental techniques per se interfere with intestinal flora, mucosal barrier function, or immune response. Interference with these major aspects of bacterial translocation complicates interpretation of study results. This paper addresses these and other issues of animal models most frequently used to study bacterial translocation during acute pancreatitis.


Assuntos
Translocação Bacteriana/fisiologia , Modelos Animais de Doenças , Pancreatite/microbiologia , Animais , Motilidade Gastrointestinal/fisiologia , Humanos , Imunidade nas Mucosas/imunologia , Mucosa Intestinal/microbiologia , Intestino Delgado/microbiologia
10.
Med Biol Eng Comput ; 45(3): 275-81, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17221257

RESUMO

Controlled distension of hollow organs is an accepted technique for generating reproducible visceral stimuli. We have constructed a new, flexible and intelligent distension system in which discomfort, pain and autonomic responses are recorded online. These responses can be fed back into the system in a regulatory loop and be used to shape the distension paradigm. Consequently, it is possible to take all subjects to a state of equal, although subjective, level of discomfort or pain, even though pressure, tension and volume might be totally different. By using a variable airflow, this new distension system can be effectively used in all kinds of paradigms, e.g. phasic, tonic, or ramp distensions or customized combinations of them. The system can be used to control pressure, volume or tension. A refinement of the system is that it is possible to automatically change the controlled entity during a distension, e.g. from an isobaric ramp directly into an isovolumetric tonic phase. Furthermore, the distension device allows double distensions with independent distension paradigms.


Assuntos
Dilatação/instrumentação , Vísceras/fisiologia , Adulto , Eletromiografia , Desenho de Equipamento , Retroalimentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/métodos , Estimulação Física/instrumentação , Estimulação Física/métodos , Pressão , Sensação
11.
Am J Physiol Gastrointest Liver Physiol ; 291(5): G950-8, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16690905

RESUMO

Patients with functional gastrointestinal disorders often demonstrate abnormal visceral sensation. Currently, rectal sensation is assessed by manual balloon distension or barostat. However, neither test is adaptable for use in the neurophysiological characterization of visceral afferent pathways by sensory evoked potentials. The aim of this study was to assess the reproducibility and quality of sensation evoked by electrical stimulation (ES) and rapid balloon distension (RBD) in the anorectum and to apply the optimum stimulus to examine the visceral afferent pathway with rectal evoked potentials. Healthy subjects (n = 8, median age 33 yr) were studied on three separate occasions. Variability, tolerance, and stimulus characteristics were assessed with each technique. Overall ES consistently invoked pain and was chosen for measuring rectal evoked potential whereas RBD in all cases induced the strong urge to defecate. Rectal intraclass correlation coefficient (ICC) for ES and RBD (0.82 and 0.72, respectively) demonstrated good reproducibility at pain/maximum tolerated volume but not at sensory threshold. Only sphincter ICC for ES at pain showed acceptable between-study reproducibility (ICC 0.79). Within studies ICC was good (>0.6) for anorectal ES and RBD at both levels of sensation. All subjects reported significantly more unpleasantness during RBD than ES (P < 0.01). This study demonstrates that ES and RBD are similarly reproducible. However, the sensations experienced with each technique differed markedly, probably reflecting differences in peripheral and/or central processing of the sensory input. This is of relevance in interpreting findings of neuroimaging studies of anorectal sensation and may provide insight into the physiological characteristics of visceral afferent pathways in health and disease.


Assuntos
Canal Anal/inervação , Canal Anal/fisiologia , Reto/inervação , Reto/fisiologia , Adolescente , Adulto , Ansiedade/psicologia , Cateterismo , Estimulação Elétrica , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Dor/psicologia , Medição da Dor , Estimulação Física , Valores de Referência , Reprodutibilidade dos Testes , Sensação/fisiologia
12.
Ned Tijdschr Geneeskd ; 150(10): 535-40, 2006 Mar 11.
Artigo em Holandês | MEDLINE | ID: mdl-16566415

RESUMO

Acute pancreatitis has a high mortality in case of secondary infection of (peri-)pancreatic necrosis. Bacterial translocation is held responsible for the majority of these infectious complications of severe acute pancreatitis. Prophylactic strategies should therefore be directed at the three most important pathophysiological mechanisms of bacterial translocation: disturbed small-bowel motility and bacterial overgrowth, failure of the mucosal barrier function and a disturbed response of the immune system. In-vitro studies and research in experimental animals have shown that specially selected probiotics exert an effect on these mechanisms and can prevent bacterial translocation. Recently, several randomised, double-blind, placebo-controlled trials evaluating prophylactic treatment with enteral probiotics have shown good results. A Dutch multicentre trial, 'Probiotics in pancreatitis trial' (PROPATRIA), is currently underway.


Assuntos
Controle de Infecções/métodos , Pancreatite Necrosante Aguda/complicações , Probióticos/administração & dosagem , Translocação Bacteriana/efeitos dos fármacos , Humanos , Pancreatite Necrosante Aguda/mortalidade , Probióticos/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Eur J Clin Invest ; 36(2): 105-12, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16436092

RESUMO

BACKGROUND: Indomethacin (Indo) exerts local toxic effects on small intestinal mucosa, possibly in association with hydrophobic bile salts. We investigated the potential toxic effects of Indo on ileal mucosa and the role of phosphatidylcholine (PC). MATERIALS AND METHODS: Transmucosal resistance and Na-fluorescein permeability of ileal mucosa segments from female Wistar rats were determined in Ussing chambers during a 30-min incubation with model systems containing: control-buffer, taurodeoxycholate (TDC), Indo, TDC-Indo, TDC-PC, or TDC-PC-Indo. Decrease of resistance and increase of permeability were considered as parameters for mucosal injury. After incubation in Ussing chambers, the histopathology was examined to quantify the extent of mucosal injury. Also, in CaCo-2 cells, LDH-release was determined as a measure of cytotoxicity, after incubation with various model systems. RESULTS: Decrease of resistance and increase of permeability were highest in systems containing TDC-Indo (P < 0.01). Phosphatidylcholine protected against the cytotoxic effects of TDC in absence of Indo only. Extent of mucosal injury by histological examination was also highest in systems containing TDC-Indo (P = 0.006). Again, PC exhibited protective effects in absence of Indo only. The LDH-release by CaCo2-cells was strongest in TDC-Indo systems (P < 0.001). CONCLUSIONS: Indomethacin disrupts protective effects of PC against bile salt-induced ileal mucosa injury. This finding is relevant for small intestinal injury induced by non-steroidal anti-inflammatory drugs.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Íleo/lesões , Indometacina/efeitos adversos , Mucosa Intestinal/lesões , Fosfatidilcolinas/metabolismo , Animais , Células CACO-2 , Colagogos e Coleréticos/metabolismo , Feminino , Humanos , Íleo/metabolismo , Íleo/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , L-Lactato Desidrogenase/metabolismo , Permeabilidade , Ratos , Ratos Wistar , Ácido Taurodesoxicólico/metabolismo
14.
Neurogastroenterol Motil ; 17(5): 654-62, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16185303

RESUMO

This study investigated the relationship between the oesophageal acid exposure time and the underlying manometric motor events in patients with gastro-oesophageal reflux disease (GORD). In 31 patients, 3-hour oesophageal motility and pH were measured after a test meal. Ten patients underwent 24-hour ambulatory manometry and pH recording. In the 3-hour postprandial study, of 367 reflux episodes 79% was associated with a transient lower oesophageal sphincter relaxation (TLOSR), 14% with absent basal lower oesophageal sphincter (LOS) pressure and the remaining 7% with other mechanisms, representing 62, 28 and 10% of the acid exposure time, respectively. Acid reflux duration per motor mechanism was longer for absent basal LOS pressure than for TLOSR (189 +/- 23 s and 41 +/- 5 s, respectively, P < 0.001). In the 24-hour ambulatory study, the contribution of TLOSRs to reflux frequency vs acid exposure time were 65 vs 54% interprandially and 74 vs 53% after the meal. During the night, absence of basal LOS pressure accounted for 36% of reflux events representing 71% of acid exposure time. In conclusion, the duration of oesophageal acid exposure following a TLOSR is shorter than reflux during absent basal LOS pressure. TLOSRs are, the major contributor to oesophageal acid exposure during the day. At night, however, reflux during absent basal LOS pressure is the major contributor to acid exposure.


Assuntos
Esôfago/fisiologia , Ácido Gástrico/metabolismo , Refluxo Gastroesofágico/fisiopatologia , Adulto , Idoso , Ritmo Circadiano , Esôfago/fisiopatologia , Feminino , Refluxo Gastroesofágico/complicações , Motilidade Gastrointestinal , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Monitorização Ambulatorial , Período Pós-Prandial
16.
Neurogastroenterol Motil ; 17(3): 341-7, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15916621

RESUMO

BACKGROUND: With each swallow a certain amount of air is transported to the stomach. The stomach protects itself against excessive distention by swallowed air through belching (gas reflux). The mechanism of belching (transient lower oesophageal sphincter relaxation) is also one of the mechanisms underlying gastro-oesophageal reflux. AIM: To investigate whether swallowing of air leads to an increase in size of the intragastric air bubble and to gastro-oesophageal reflux. METHODS: Multichannel intraluminal impedance measurement was used to quantify the incidence of swallowing of air in 20 healthy volunteers before and after a meal. Radiography was used to measure the size of the intragastric air bubble. Gastro-oesophageal reflux was assessed by concurrent impedance and pH measurement. RESULTS: The rate of air swallowing was correlated to the size of the intragastric air bubble postprandially and to the rate of gaseous gastro-oesophageal reflux. The number of air swallows and the size of the intragastric air bubble did not correlate with the number of liquid acid and non-acid reflux episodes. CONCLUSIONS: In healthy subjects, air swallowing promotes belching but does not facilitate acid reflux.


Assuntos
Deglutição/fisiologia , Eructação/fisiopatologia , Refluxo Gastroesofágico/fisiopatologia , Estômago/fisiologia , Adulto , Ar , Ingestão de Alimentos/fisiologia , Impedância Elétrica , Eructação/diagnóstico por imagem , Esôfago/fisiologia , Feminino , Fluoroscopia , Refluxo Gastroesofágico/diagnóstico por imagem , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Período Pós-Prandial , Estômago/anatomia & histologia , Estômago/diagnóstico por imagem
17.
Curr Issues Intest Microbiol ; 6(1): 1-7, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15751747

RESUMO

In a young evolving science, there are always more questions than answers. That is also the situation in the emerging field of Probiotics, and this was made very clear at the International Probiotics Workshop in Amsterdam. In the report of this workshop, we present a selection of the most urgent questions in the field of probiotics. In addition, we propose a few strategies for the future of probiotics research. During the workshop, 120 experts--from disciplines including Human Nutrition, Gastroenterology, Nutritional Therapy, Cell Biology, Microbiology and Immunology--discussed new views on microbe-host interactions and the role of probiotics in prevention and alleviation of gastro-intestinal, atopic and auto-immune diseases. There is a general consensus among the experts that administering defined strains can help in preventing and curing gut flora related diseases: the first clinical trials show a promising role for probiotics. But the system is very complex, and most underlying mechanisms are still unclear. Rapid progress in this field will depend largely on the collaboration between fundamental researchers from different disciplines and medical specialists. Besides, more clinical studies are required to convince authorities and the public of the value of microbial therapies.


Assuntos
Infecções Bacterianas/dietoterapia , Doenças Inflamatórias Intestinais/microbiologia , Intestinos/microbiologia , Probióticos/uso terapêutico , Animais , Humanos , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/terapia , Intestinos/imunologia
18.
Neurogastroenterol Motil ; 16(6): 819-28, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15601432

RESUMO

Alterations in L-arginine availability and nitric oxide (NO) synthesis in the intestinal muscularis may contribute to disturbed small intestinal motility that is observed during endotoxaemia. The aim of this study was to evaluate the effect of L-arginine infusion on visceral NO production and jejunal motility in hyperdynamic compensated endotoxaemic pigs. Fasted and saline-resuscitated pigs were intravenously infused for 24 h with endotoxin (lipopolysaccharide, 50 ng kg(-1) min(-1)) or saline (n = 6). Endotoxaemic pigs received either intravenous L-arginine (n = 6, 5.3 micromol kg(-1) min(-1)) or L-alanine (isocaloric, n = 6). After 24 h, intravenous L-arginine or L-alanine infusion was continued intragastrically for 32-h in an enteral meal. During (0-24 h) and 1 day postendotoxaemia (48-56 h), jejunal motility was recorded by manometry and analysed for migrating motor complex (MMC) characteristics. Visceral NO production was measured at 24 and 48 h by 15N2-arginine-to-15N-citrulline conversion. Visceral NO production was increased during endotoxaemia and was higher in L-arginine than in L-alanine-treated pigs. One day postendotoxaemia, visceral NO synthesis was still increased in L-arginine but not in L-alanine-treated animals. Endotoxaemia shortened the MMC cycle duration and accelerated the MMC propagation velocity. Both were restored by L-arginine. Similar motility disturbances were observed one day postendotoxaemia and were also compensated by L-arginine infusion.


Assuntos
Arginina/administração & dosagem , Endotoxemia/fisiopatologia , Motilidade Gastrointestinal/efeitos dos fármacos , Jejuno/efeitos dos fármacos , Complexo Mioelétrico Migratório/efeitos dos fármacos , Óxido Nítrico/biossíntese , Alanina/administração & dosagem , Animais , Arginina/sangue , Feminino , Motilidade Gastrointestinal/fisiologia , Infusões Intravenosas , Jejuno/fisiologia , Manometria , Complexo Mioelétrico Migratório/fisiologia , Sus scrofa , Fatores de Tempo
19.
Dig Surg ; 21(5-6): 371-8; discussion 379, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15499222

RESUMO

BACKGROUND: Ileo-neorectal anastomosis (INRA), an alternative restorative procedure, was developed to reduce the pouch-related complication rate with an (at least) equal functional result. METHODS: For this surgical outcome, data of all INRA patients, including bowel function and complications, were prospectively recorded. The reservoir capacity was determined repeatedly by physiologic tests. The anal sphincter complex was assessed by manometry and ultrasound examination. Evaluation of the neorectal mucosa was performed by endoscopy. RESULTS: An INRA procedure was carried out in 39/53 selected patients (47 ulcerative colitis and 6 familial adenomatous polyposis). Fourteen UC cases were converted to ileal pouch anal anastomosis or proctectomy only, because of impossibility to completely remove the rectal mucosa or short of length of the rectal stump. The median operation time for INRA was 323 min (range 240-518), with 1,400 ml blood loss (400-4,500). The reservoirs were permanently defunctioned in 2 patients--one because of reclassification into Crohn's disease, and one with pouchitis refractory to medical treatment. In 18 out of 37 cases, web-like stenoses occurred at the mucosa-anal level, which were treated by single (9) or repeated (5) dilatation or surgical stenoplasty (2). No pouch-related complications like pelvic sepsis, fistula or sexual dysfunction occurred. Thirteen patients had episodes of 'pouchitis', successfully treated with antibiotics, and 7 other cases, with functioning reservoirs, also had proximal 'non-specific' (i.e. no histological criteria of Crohn's disease found) small bowel inflammation. The median bowel frequency decreased from 15x/24 h initially to 7x/24 h at 2 years. Continence was perfect in 24/37 cases. Twelve out of 37 cases had occasional nocturnal soiling and passive nocturnal fecal incontinence was reported by 2/37 patients. The neorectal compliance volume recovered from 12.5 ml kPa after subtotal colectomy and 11 ml/kPa at 6 months after INRA to a neorectal compliance of 24 ml/kPa at 2 years' follow-up (p < 0.002; Wilcoxon signed rank test). CONCLUSION: The INRA procedure shows a low complication rate and reasonable functional results, there was however a considerable conversion rate in these first 53 cases and a high incidence of reclassification to CD.


Assuntos
Colite Ulcerativa/cirurgia , Proctocolectomia Restauradora/métodos , Competência Clínica , Feminino , Seguimentos , Humanos , Masculino , Manometria , Resultado do Tratamento
20.
J Physiol ; 555(Pt 2): 573-83, 2004 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-14724212

RESUMO

Stretching the stomach wall in young healthy subjects causes an increase in muscle sympathetic nerve activity and in blood pressure, the gastrovascular reflex. We compared healthy elderly subjects with healthy young subjects to find out whether the gastrovascular reflex attenuates in normal ageing and we studied whether there was a difference in autonomic function or gastric compliance that could explain this possible attenuation. Muscle sympathetic nerve activity, finger blood pressure and heart rate were continuously recorded during stepwise isobaric gastric distension using a barostat in eight healthy young (6 men and 2 women, 27 +/- 3.2 years, mean +/-s.e.m.) and eight healthy elderly subjects (7 men and 1 woman, 76 +/- 1.5 years). Changes in cardiac output and total peripheral arterial resistance were calculated from the blood pressure signal. The baseline mean arterial pressure and muscle sympathetic nerve activity were higher in the elderly group (both P < 0.05) and muscle sympathetic nerve activity increase during the cold pressor test was lower in the elderly group (P = 0.005). During stepwise gastric distension, the elderly subjects showed an attenuated increase in muscle sympathetic nerve activity compared to the young subjects (P < 0.01). The older group tended to show a higher increase in mean arterial pressure (P = 0.08), heart rate (P = 0.06) and total peripheral arterial resistance (P = 0.09) The cardiac output rose slightly in both groups without significant difference between groups. The fundic compliance did not differ between groups. We conclude that stepwise gastric distension caused an increase in muscle sympathetic nerve activity in both groups, but the increase in the elderly was attenuated.


Assuntos
Hemodinâmica/fisiologia , Reflexo/fisiologia , Estômago/irrigação sanguínea , Estômago/fisiologia , Idoso , Pressão Sanguínea/fisiologia , Débito Cardíaco/fisiologia , Temperatura Baixa , Complacência (Medida de Distensibilidade) , Eletrocardiografia , Frequência Cardíaca/fisiologia , Humanos , Pressão , Fluxo Sanguíneo Regional/fisiologia , Estômago/inervação , Gastropatias/fisiopatologia , Gastropatias/psicologia , Sistema Nervoso Simpático/fisiologia , Manobra de Valsalva , Resistência Vascular/fisiologia
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