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1.
Gut ; 62(1): 122-30, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22580416

RESUMO

BACKGROUND: Diagnosis and curative treatment of cholangiocarcinoma (CC) often comes too late due to the lack of reliable tumour markers especially in patients with primary sclerosing cholangitis (PSC). The authors recently introduced bile proteomic analysis for CC diagnosis. Nevertheless, bile collection depends on invasive endoscopic retrograde cholangiography. The authors therefore evaluated urine proteomic analysis for non-invasive CC diagnosis. METHODS: Using capillary electrophoresis mass spectrometry the authors established a CC-specific peptide marker model based on the distribution of 42 peptides in 14 CC, 13 PSC and 14 benign biliary disorder (BBD) patients. RESULTS: In cross-sectional validation of 123 patients, the urine peptide marker model correctly classified 35 of 42 CC patients and 64 of 81 PSC and BBD patients with an area under the curve value of 0.87 (95% CI 0.80 to 0.92, p=0.0001, 83% sensitivity, 79% specificity). Evaluation of 101 normal controls resulted in 86% specificity. All 10 patients with CC on top of PSC were correctly classified. The majority of sequence-identified peptides are fragments of interstitial collagens with some of them also detected in blood indicating their extra-renal origin. Immunostaining of liver sections for matrix metallopeptidase 1 indicated increased activity of the interstitial collagenase in liver epithelial cells of CC patients. CONCLUSION: The urine test differentiates CC from PSC and other BBD and may provide a new diagnostic non-invasive tool for PSC surveillance and CC detection.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico , Ductos Biliares Intra-Hepáticos , Biomarcadores/urina , Colangiocarcinoma/diagnóstico , Colangite Esclerosante/diagnóstico , Proteômica , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/urina , Estudos de Casos e Controles , Colangiocarcinoma/urina , Colangite Esclerosante/urina , Análise por Conglomerados , Estudos Transversais , Diagnóstico Diferencial , Eletroforese Capilar , Feminino , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Mapeamento de Peptídeos , Sensibilidade e Especificidade
2.
Gastrointest Endosc ; 78(2): 303-11, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23642489

RESUMO

BACKGROUND: Pancreatitis is a potentially life-threatening condition frequently accompanied by peri-pancreatic fluid collections (PPFC), such as pseudocysts or pancreatic necrosis. Aspiration of PPFCs during EUS interventions for microbiologic analysis is still rarely performed in clinical routine. OBJECTIVE: To evaluate the role of routine microbiologic analysis of PPFCs and its impact on antibiotic therapy in patients with pancreatitis. DESIGN: Prospective, observational, multicenter study. SETTING: Four treatment centers. PATIENTS: A total of 44 consecutive patients who presented for endoscopic treatment of PPFCs were included. INTERVENTION: Concomitantly, PPFC during intervention and concomitant blood cultures were obtained. MAIN OUTCOME MEASUREMENTS: Microbiologic examination of PPFCs and blood samples. RESULTS: Colonization of PPFCs was found in 59% of PPFC cultures, whereas all but 2 concomitant blood cultures showed no microbial growth. Risk factors for a colonization were the presence of necrosis (P = .006), acute pancreatitis (P = .033), leukocytosis (P = .001), elevated C-reactive protein levels (P = .003), fever (P = .02), turbid material (P = .031), and longer hospital stay (P = .003). In 23 patients with fluid colonization despite empiric antibiotic therapy, the treatment had to be adjusted in 18 patients (78%) according to the observed antibiotic susceptibility profile. LIMITATIONS: Contamination cannot be totally excluded. CONCLUSION: The microbiologic colonization of PPFCs in patients with pancreatitis is common. Only the direct microbiologic analysis of PPFCs, but not of blood cultures, is useful to optimize an effective antibiotic therapy in patients with pancreatitis.


Assuntos
Líquido Cístico/microbiologia , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Pâncreas/diagnóstico por imagem , Pseudocisto Pancreático/microbiologia , Pancreatite/microbiologia , Adulto , Idoso , Antibacterianos/uso terapêutico , Estudos de Coortes , Contagem de Colônia Microbiana , Endossonografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pseudocisto Pancreático/diagnóstico por imagem , Pancreatite/diagnóstico por imagem , Pancreatite/tratamento farmacológico , Pancreatite Alcoólica/diagnóstico por imagem , Pancreatite Alcoólica/microbiologia , Pancreatite Crônica/diagnóstico por imagem , Pancreatite Crônica/microbiologia , Estudos Prospectivos
3.
Clin Transplant ; 27(2): E161-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23383749

RESUMO

The indication for mandatory screening colonoscopies in liver transplant candidates is controversial. Since the introduction of MELD-based allocation, patients with advanced liver disease and often severe comorbidities are prioritized for liver transplantation (LT). This study evaluated safety and outcome of colonoscopy in this high-risk patient group. During a two-yr period, we performed 243 colonoscopies in potential LT candidates. Endoscopic findings were registered in a standardized form, and correlations with biochemical or clinical parameters were analyzed using Mann-Whitney U-test and chi-square test. Only 57 patients (23.5%) had an endoscopically normal colon. Main findings were polyps (45.7%), hypertensive colopathy (24.3%), diverticulosis (21%), rectal varices (19.8%), and hemorrhoids (13.6%). In 21% of all patients, the removed polyps were diagnosed as adenomas. The prevalence of neoplastic polyps increased significantly with age: 13.6% (patients <50 yr) vs. 25% (patients ≥ 50 yr) (p = 0.03). Advanced neoplasia was found only in patients older than 40 yr. No major complications were observed; post-interventional hemorrhage was observed in 1.7% and controlled by clipping or injection therapy. In conclusion, lower gastrointestinal endoscopy is safe and effective in LT candidates. Due to the age dependency of neoplastic polyps, a screening colonoscopy should be performed in LT candidates older than 40 yr or with symptoms or additional risk factors.


Assuntos
Doenças do Colo/diagnóstico , Colonoscopia , Doença Hepática Terminal/complicações , Transplante de Fígado , Seleção de Pacientes , Cuidados Pré-Operatórios/métodos , Adulto , Fatores Etários , Doenças do Colo/complicações , Doenças do Colo/epidemiologia , Doenças do Colo/terapia , Doença Hepática Terminal/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Risco
4.
Endosc Int Open ; 11(2): E212-E217, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36845275

RESUMO

Background and study aims Only a few studies are available regarding endoscopic vacuum-assisted closure (E-VAC) therapy for the post-surgery leakage of the lower gastrointestinal tract. Patients and methods In this multicenter German study, we retrospectively analyzed patients treated with E-VAC therapy due to post-surgery leakage of the lower gastrointestinal tract from 2000-2020 at Hannover Medical School, University Medical Center Schleswig-Holstein, Campus Luebeck, and Robert Koch Hospital Gehrden. Results Overall, 147 patients were included in this study. Most patients had undergone tumor resections of the lower gastrointestinal tract (n = 88; 59.9 %). Median time to diagnosis of leakage was 10 days (interquartile range [IQR] 6-19). Median duration of E-VAC therapy was 14 days (IQR 8-27). Increase of C-reactive protein (CRP) levels significantly correlated with first diagnosis of leakage ( P  < 0.001). E-VAC therapy led to closure or complete epithelialization of leakage in the majority of patients (n = 122; 83.0 %) and stoma reversal was achieved in 60.0 %. Stoma reversal was significantly more often achieved in patients with CRP levels ≤ 100 mg/L at first diagnosis compared to patients with CRP levels > 100 mg/L (78.4 % vs. 52.7 %; P  = 0.012). Odds ratio for failure of stoma reversal was 3.36 in cases with CRP values > 100 mg/L ( P  = 0.017). In total, leakage- and/ or E-VAC therapy-associated complications occurred in 26 patients (17.7 %). Minor complications included recurrent E-VAC dislocations and subsequent stenosis. Overall, 14 leakage- or E-VAC-associated deaths were observed most often due to sepsis. Conclusions E-VAC therapy due to post-surgery leakage of the lower gastrointestinal tract is safe and effective. High levels of CRP are a negative predictor of E-VAC therapy success.

5.
Hepatology ; 53(3): 875-84, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21374660

RESUMO

UNLABELLED: Early detection of malignant biliary tract diseases, especially cholangiocarcinoma (CC) in patients with primary sclerosing cholangitis (PSC), is very difficult and often comes too late to give the patient a therapeutic benefit. We hypothesize that bile proteomic analysis distinguishes CC from nonmalignant lesions. We used capillary electrophoresis mass spectrometry (CE-MS) to identify disease-specific peptide patterns in patients with choledocholithiasis (n = 16), PSC (n = 18), and CC (n = 16) in a training set. A model for differentiation of choledocholithiasis from PSC and CC (PSC/CC model) and another model distinguishing CC from PSC (CC model) were subsequently validated in independent cohorts (choledocholithiasis [n = 14], PSC [n = 18] and CC [n = 25]). Peptides were characterized by sequencing. Application of the PSC/CC model in the independent test cohort resulted in correct exclusion of 12/14 bile samples from patients with choledocholithiasis and identification of 40/43 patients with PSC or CC (86% specificity, 93% sensitivity). The corresponding receiver operating characteristic (ROC) analysis revealed an area under the curve (AUC) of 0.93 (95% confidence interval [CI]: 0.82-0.98, P = 0.0001). The CC model succeeded in an accurate detection of 14/18 bile samples from patients with PSC and 21/25 samples with CC (78% specificity, 84% sensitivity) in the independent cohort, resulting in an AUC value of 0.87 (95% CI: 0.73-0.95, P = 0.0001) in ROC analysis. Eight out of 10 samples of patients with CC complicating PSC were identified. CONCLUSION: Bile proteomic analysis discriminates benign conditions from CC accurately. This method may become a diagnostic tool in future as it offers a new possibility to diagnose malignant bile duct disease and thus enables efficient therapy particularly in patients with PSC.


Assuntos
Bile/química , Colangiocarcinoma/diagnóstico , Coledocolitíase/diagnóstico , Proteoma/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Colangite Esclerosante/diagnóstico , Eletroforese Capilar , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade
6.
Hepatology ; 53(6): 1977-85, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21425313

RESUMO

UNLABELLED: Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease characterized by inflammation and fibrosis of the bile ducts. Both environmental and genetic factors contribute to its pathogenesis. To further clarify its genetic background, we investigated susceptibility loci recently identified for ulcerative colitis (UC) in a large cohort of 1,186 PSC patients and 1,748 controls. Single nucleotide polymorphisms (SNPs) tagging 13 UC susceptibility loci were initially genotyped in 854 PSC patients and 1,491 controls from Benelux (331 cases, 735 controls), Germany (265 cases, 368 controls), and Scandinavia (258 cases, 388 controls). Subsequently, a joint analysis was performed with an independent second Scandinavian cohort (332 cases, 257 controls). SNPs at chromosomes 2p16 (P-value 4.12 × 10(-4) ), 4q27 (P-value 4.10 × 10(-5) ), and 9q34 (P-value 8.41 × 10(-4) ) were associated with PSC in the joint analysis after correcting for multiple testing. In PSC patients without inflammatory bowel disease (IBD), SNPs at 4q27 and 9q34 were nominally associated (P < 0.05). We applied additional in silico analyses to identify likely candidate genes at PSC susceptibility loci. To identify nonrandom, evidence-based links we used GRAIL (Gene Relationships Across Implicated Loci) analysis showing interconnectivity between genes in six out of in total nine PSC-associated regions. Expression quantitative trait analysis from 1,469 Dutch and UK individuals demonstrated that five out of nine SNPs had an effect on cis-gene expression. These analyses prioritized IL2, CARD9, and REL as novel candidates. CONCLUSION: We have identified three UC susceptibility loci to be associated with PSC, harboring the putative candidate genes REL, IL2, and CARD9. These results add to the scarce knowledge on the genetic background of PSC and imply an important role for both innate and adaptive immunological factors.


Assuntos
Proteínas Adaptadoras de Sinalização CARD/genética , Colite Ulcerativa/genética , Predisposição Genética para Doença/genética , Interleucina-2/genética , Proteínas Proto-Oncogênicas c-rel/genética , Alelos , Proteínas Adaptadoras de Sinalização CARD/fisiologia , Estudos de Casos e Controles , Colangite Esclerosante/etnologia , Colangite Esclerosante/genética , Estudos de Coortes , Colite Ulcerativa/etnologia , Predisposição Genética para Doença/etnologia , Genótipo , Alemanha , Humanos , Interleucina-2/fisiologia , Países Baixos , Polimorfismo de Nucleotídeo Único/genética , Proteínas Proto-Oncogênicas c-rel/fisiologia , Locos de Características Quantitativas , Países Escandinavos e Nórdicos
7.
Gastrointest Endosc ; 76(6): 1238-41, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23025973

RESUMO

BACKGROUND: Endoscopic transluminal débridement of infected pancreatic necrosis has been proved to be an important alternative to surgical débridement. Recently, endoscopic vacuum-assisted closure (EVAC) has been described as a new effective treatment option in upper intestinal anastomotic leaks. OBJECTIVE: To test whether the EVAC can be applied to transgastrically accessible infected cavities. DESIGN: Single-center case study. SETTING: Academic medical center. PATIENTS: Two patients with necrotizing pancreatitis. MAIN OUTCOME MEASUREMENT: Successful closure of leak. RESULTS: We successfully applied EVAC to treat transgastrically accessible necrotic cavities. LIMITATIONS: Small case number. CONCLUSIONS: EVAC might be an important additional endoscopic treatment option for infected pancreatic necrosis, especially if established endoscopic treatment options fail.


Assuntos
Endoscopia do Sistema Digestório/métodos , Tratamento de Ferimentos com Pressão Negativa/métodos , Pancreatite Necrosante Aguda/terapia , Endoscopia do Sistema Digestório/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Tratamento de Ferimentos com Pressão Negativa/instrumentação , Tampões de Gaze Cirúrgicos
8.
J Immunol ; 185(1): 119-25, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20511546

RESUMO

Mast cells (MCs) that are well known for their important effector function in IgE-associated immune responses play a key role in innate immune defenses. In this study, we investigate the interaction between MCs and NK cells in vitro and in vivo. We show that mouse bone marrow-derived cultured MCs activated with LPS, polyinosinic-polycytidylic acid, or CpG can stimulate NK cells to secrete increasing concentrations of IFN-gamma. MCs induce a 20-fold increase in IFN-gamma release from NK cells after LPS stimulation. This enhancement of IFN-gamma secretion is cell contact dependent and TNF-alpha independent. Furthermore, we show that this interaction is in part mediated by OX40 ligand on MCs. NK cell-mediated cytotoxicity was not affected by the presence of MCs. Intracellular IFN-gamma levels in splenic NK cells are significantly decreased after i.p. injection of LPS in mast cell-deficient (C57BL/6 Kit(wsh/wsh)) mice in comparison with wild-type mice. In conclusion, our data show for the first time a direct mast cell-dependent NK cell activation. This interaction might play an important role in innate immune defense, as it is dependent on the presence of stimulators relevant in innate immune responses.


Assuntos
Interferon gama/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Lipopolissacarídeos/fisiologia , Mastócitos/imunologia , Mastócitos/metabolismo , Animais , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Comunicação Celular/imunologia , Células Cultivadas , Técnicas de Cocultura , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor 3 Toll-Like/fisiologia , Receptor 4 Toll-Like/fisiologia , Receptor Toll-Like 9/fisiologia , Fator de Necrose Tumoral alfa/deficiência , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/fisiologia
9.
Ann Hepatol ; 10(1): 38-42, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21301008

RESUMO

BACKGROUND: Intestinal intussusception in adults is associated with chronic inflammatory bowel disease, celiac disease, abdominal tumors or previous abdominal surgery but most often of unknown origin. AIM: The aim of our study was to evaluate circumstances and identify risk factors for intussusceptions. METHODS: All 65,928 abdominal ultrasound examinations performed at our tertiary medical center between January 2001 and June 2008 were analyzed retrospectively for the diagnosis "intussusception". After identifying individuals with sonographically proven intussusception we analyzed various patients' characteristics including age, gender and underlying disease as well as sonographic findings such as localization of the intussusception, absence or presence of ascites and lymph nodes. RESULTS: We identified 32 cases of intussusceptions [mean age 45 years (range 18 to 88); 18 patients were male]. Twelve patients (38%) had a history of abdominal surgery including 8 patients who had undergone liver transplantation (2 patients with primary sclerosing cholangitis, 1 patient with cystic fibrosis, 1 patient with sarcoidosis, 1 patient with hepatocellular carcinoma and HCV infection, 1 patient with autoimmune hepatitis, 1 patient with Crigler-Najar-syndrome and one patient with echinococcus). A hepaticojejunostomy had been performed in 4 of the patients after liver transplantation. Liver transplanted patients were significantly overrepresented in the intussusceptions group compared with the overall cohort of patients undergoing abdominal ultrasound examination (25% vs. 8%, Chi-Square-test, p = 0.0023). CONCLUSION: In our retrospective study liver transplantation, in particular with hepaticojejunostomy, was identified as a new major risk factor for intestinal intussusceptions


Assuntos
Enteropatias/etiologia , Intussuscepção/etiologia , Transplante de Fígado/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Feminino , Alemanha , Humanos , Imunossupressores/efeitos adversos , Enteropatias/diagnóstico por imagem , Intussuscepção/diagnóstico por imagem , Jejunostomia/efeitos adversos , Doenças Linfáticas/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Ultrassonografia , Adulto Jovem
10.
Gastrointest Endosc ; 71(2): 382-6, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19879566

RESUMO

BACKGROUND: Endoscopic treatment options for postsurgical intrathoracic leaks include injection of fibrin glue, clip application, and stent placement. Endoscopic vacuum-assisted closure (E-VAC) may be an effective treatment option. OBJECTIVE: To demonstrate that E-VAC is an effective endoscopic treatment option for closure of major intrathoracic postsurgical leaks. DESIGN AND SETTING: A prospective, single-center study at an academic medical center. PATIENTS: Eight consecutive patients with major intrathoracic postsurgical leaks. INTERVENTIONS: Endoscopic placement of transnasal draining tubes, armed with a size-adjusted sponge at their distal end, in the necrotic anastomotic cavities, followed by continuous suction. Sponge and drainage were changed twice weekly. Patients were followed-up for 193 +/- 137 days. MAIN OUTCOME MEASUREMENT: Successful leak closure. RESULTS: Successful closure of leaks was achieved in 7 of 8 patients (88%) after a mean of 23 +/- 8 days. A median of 7 endoscopic interventions was necessary. No major treatment-associated short-term or long-term (follow-up, 193 +/- 137 days) complications were noted. LIMITATIONS: Small sample size, single-center study, and lack of randomization. CONCLUSION: E-VAC is an effective endoscopic treatment modality for major postsurgical intrathoracic leaks. (This study is registered at Clinicaltrials.gov, identifier NCT00876551.).


Assuntos
Anastomose Cirúrgica/efeitos adversos , Fístula/cirurgia , Tratamento de Ferimentos com Pressão Negativa , Doenças Torácicas/cirurgia , Centros Médicos Acadêmicos , Idoso , Anastomose Cirúrgica/métodos , Endoscopia/métodos , Esofagectomia/efeitos adversos , Esofagectomia/métodos , Feminino , Fístula/etiologia , Seguimentos , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/cirurgia , Estudos Prospectivos , Medição de Risco , Estudos de Amostragem , Doenças Torácicas/etiologia , Resultado do Tratamento
11.
Gastrointest Endosc ; 72(2): 284-91, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20541201

RESUMO

BACKGROUND: Antibiotic treatment of cholangitis is often insufficient because of inappropriate antibiotic use or bacterial resistance. OBJECTIVE: To evaluate the role of routine bile collection during endoscopic retrograde cholangiography or percutaneous transhepatic cholangiography for microbiological analysis in the antibiotic management of cholangitis and to identify risk factors of bacteriobilia. DESIGN: Prospective, observational, diagnostic study. SETTING: Hannover Medical School, Hannover, Germany. PATIENTS AND INTERVENTION: This study involved 243 consecutive patients undergoing endoscopic retrograde cholangiography/percutaneous transhepatic cholangiography for biliary complications after orthotopic liver transplantation (27%), malignancy (27%), primary sclerosing cholangitis (15%), benign strictures (11%), and choledocholithiasis (8%). MAIN OUTCOME MEASUREMENTS: Microbiological examination of bile samples. RESULTS: Patients with biliary stents or who were receiving repeated interventions after orthotopic liver transplantation were at increased risk of bacteriobilia (P < .05). The rate of gram-positive monomicrobial infection was higher in patients with primary sclerosing cholangitis (P < .01). In 40 examinations, patients presented with preprocedural cholangitis although they were receiving antibiotics. According to bile culture results, the antibiotic treatment was modified to a more specific therapy in 72.5% of patients. In patients who developed cholangitis after endoscopic retrograde cholangiography (27 examinations), specific antibiotic treatment was started or refined in 67% of cases, based on bile culture results. LIMITATIONS: Contamination of samples during intervention cannot be totally excluded. CONCLUSION: Orthotopic liver transplantation, biliary stenting, and repeated interventions are risk factors of bacteriobilia. In our patients with primary sclerosing cholangitis, gram-positive monomicrobial infections were more common. A bile sample collected during cholangiography for microbiological analysis is a simple, potentially valuable, diagnostic tool in patients with cholangitis. Each center should recognize its own patterns of infection to ensure ideal targeted therapy.


Assuntos
Bactérias/isolamento & purificação , Bile/microbiologia , Colangiografia/métodos , Colangite/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Colangite/tratamento farmacológico , Colangite/microbiologia , Contagem de Colônia Microbiana , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Adulto Jovem
12.
Nature ; 432(7016): 512-6, 2004 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-15543132

RESUMO

Endothelin-1 (ET-1) is a 21-amino-acid peptide, derived from vascular endothelial cells, with potent vasoconstrictor activity. ET-1 has been implicated in diverse physiological or pathological processes, including the vascular changes associated with sepsis. However, the factors that regulate ET-1-associated toxicity during bacterial infections, or in other settings, are not fully understood. Both the pathology associated with certain allergic and autoimmune disorders, and optimal host defence against bacterial and parasitic infections are mediated by mast cells. In vitro, mast cells can produce ET-1 (ref. 11), undergo ET-1-dependent and endothelin-A receptor (ET(A))-dependent activation, and release proteases that degrade ET-1 (ref. 14). Although the potential relationships between mast cells and the ET-1 system thus may be complex, the importance of interactions between ET-1 and mast cells in vivo is obscure. Here we show that ET(A)-dependent mast-cell activation can diminish both ET-1 levels and ET-1-induced pathology in vivo, and also can contribute to optimal survival during acute bacterial peritonitis. These findings identify a new biological function for mast cells: promotion of homeostasis by limiting the toxicity associated with an endogenous mediator.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Ácido Egtázico/análogos & derivados , Endotelina-1/antagonistas & inibidores , Endotelina-1/toxicidade , Homeostase/fisiologia , Mastócitos/fisiologia , Animais , Temperatura Corporal , Peso Corporal , Degranulação Celular/efeitos dos fármacos , Sobrevivência Celular , Quimases , Diarreia/induzido quimicamente , Ácido Egtázico/farmacologia , Endotelina-1/administração & dosagem , Endotelina-1/deficiência , Feminino , Injeções Intraperitoneais , Mastócitos/citologia , Mastócitos/enzimologia , Mastócitos/transplante , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação/genética , Oligopeptídeos/farmacologia , Peptídeos Cíclicos/farmacologia , Peritonite/fisiopatologia , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Serina Endopeptidases/metabolismo , Células-Tronco/citologia , Taxa de Sobrevida
13.
J Hepatol ; 51(6): 1055-60, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19726099

RESUMO

BACKGROUND/AIMS: Timely diagnosis of biliary atresia (BA) requires key investigations that are less invasive but as accurate as possible. Non-invasive imaging preselects patients before explorative laparotomy is performed. The purpose of this prospective study was to evaluate the accuracy of endoscopic retrograde cholangiopancreaticography (ERCP) in these patients and to discuss its relevance to future diagnostic guidelines in neonatal jaundice. METHODS: Over a 7-year period, ERCP was routinely performed in cholestatic patients less than 6 months of age suspected for an extrahepatic origin of cholestasis, most likely BA. Endoscopic diagnosis was correlated with intraoperative findings. RESULTS: In 140 consecutive patients (mean age: 60 days; weight: 4 kg), ERCP excluded BA in 34 (25%) but failed in 18 newborns (13%) for technical reasons. The average procedure time was 23 min, and no severe complications occurred. Explorative laparotomy was performed in 106 patients and revealed BA in 80 cases. In this series, the sensitivity of ERCP for diagnosing biliary atresia was 92% and specificity was 73%. CONCLUSIONS: In preselected patients, ERCP is not an alternative to non-invasive imaging, but it avoids unnecessary surgical procedures in almost 25% of the cases. Hence, ERCP is recommended prior to explorative laparotomy in all patients suspected for BA.


Assuntos
Atresia Biliar/diagnóstico , Colangiopancreatografia Retrógrada Endoscópica , Atresia Biliar/diagnóstico por imagem , Atresia Biliar/cirurgia , Procedimentos Cirúrgicos do Sistema Biliar , Colangiopancreatografia Retrógrada Endoscópica/estatística & dados numéricos , Colestase Extra-Hepática/diagnóstico , Colestase Extra-Hepática/diagnóstico por imagem , Colestase Extra-Hepática/cirurgia , Humanos , Lactente , Recém-Nascido , Icterícia Obstrutiva/diagnóstico , Icterícia Obstrutiva/diagnóstico por imagem , Icterícia Obstrutiva/cirurgia , Laparotomia , Valor Preditivo dos Testes , Sensibilidade e Especificidade
15.
Artigo em Inglês | MEDLINE | ID: mdl-18492570

RESUMO

Eosinophils have been implicated in the pathogenesis of inflammatory bowel disease (IBD). Immunohistopathological studies have revealed accumulation and activation of eosinophils in actively inflamed intestinal mucosa of Crohn's disease and ulcerative colitis patients. Elevated levels of chemokines relevant for eosinophil chemotaxis and mediator release from eosinophils can be detected in serum and faeces of patients with active IBD. Animal studies have revealed that abrogation of chemokines (such as eotaxin) promoting eosinophil chemotaxis and circulation results in decreased severity of murine experimental colitis, suggesting a pro-inflammatory role for eosinophils in IBD. Furthermore, selective deletion of certain eosinophil-specific granule products results in attenuation of experimental intestinal inflammation. Shortly after their initial discovery by Ehrlich, eosinophils have been associated with intestinal tumours. However, as only very few studies have addressed the role of eosinophils in intestinal cancerogenesis, their impact on intestinal tumour development remains obscure; in particular, functional data are missing.


Assuntos
Eosinófilos/fisiologia , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/patologia , Neoplasias Intestinais/etiologia , Neoplasias Intestinais/patologia , Quimiocinas/fisiologia , Humanos , Doenças Inflamatórias Intestinais/terapia , Neoplasias Intestinais/terapia
16.
Int J Hematol ; 75(4): 363-9, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12041665

RESUMO

The sudden and systemic activation of mediator release from mast cells and basophils that can occur when some sensitized subjects are challenged by minute amounts of specific antigen (eg, from an insect sting or peanuts) can result in fatal anaphylaxis, a reaction that arguably represents the most grotesque imbalance between the cost and benefit of an immune response. Why then do mast cells and basophils continue to exist and, in the case of mast cells, populate almost all vascularized tissues? This review will consider the roles of mast cells and basophils in health and disease, emphasizing particularly their proven or potential functions in host defense. We will also describe briefly some approaches to investigate mast cell and basophil functions in vivo, including the use of mast cells generated directly from embryonic stem cells in vitro.


Assuntos
Basófilos/imunologia , Imunidade Celular , Mastócitos/imunologia , Animais , Basófilos/metabolismo , Basófilos/fisiologia , Humanos , Imunidade Celular/fisiologia , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Mastócitos/metabolismo , Mastócitos/fisiologia
17.
Int J Hematol ; 75(4): 345-9, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12041662

RESUMO

Large quantities of highly enriched populations of mast cells can be generated from mouse embryonic stem (ES) cells using an in vitro differentiation system. These embryonic stem cell-derived mast cells (ESMCs) exhibit many similarities to mouse bone marrow-derived cultured mast cells (BMCMCs), including the abilities to survive and to orchestrate immunologically specific immunoglobulin E (IgE)-dependent reactions in vivo after transplantation into genetically mast cell-deficient KitW/KitW-v mice. Coupled with the current spectrum of techniques for genetically manipulating ES cells, ESMCs represent a unique model system to analyze the effects of specific alterations in gene structure, expression, or function, including embryonic lethal mutations, on mast cell development, phenotype, and function in vitro and in vivo.


Assuntos
Mastócitos/citologia , Células-Tronco/citologia , Animais , Diferenciação Celular/genética , Embrião de Mamíferos/citologia , Métodos , Camundongos , Modelos Animais , Mutagênese Sítio-Dirigida , Recombinação Genética
18.
World J Gastroenterol ; 10(19): 2859-63, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15334686

RESUMO

AIM: Pelvic magnetic resonance imaging (MRI) and endoanal ultrasound which are established imaging methods for perianal inflammatory lesions in patients with Crohn's disease require expensive specialized equipments and expertise. We investigated the feasibility and sensitivity of transcutaneous perianal ultrasound (PAUS) using regular ultrasound probes in the imaging of perianal inflammatory lesions. The sonographic findings were correlated to pelvic MRI-scans. METHODS: We performed PAUS in 25 patients with Crohn's disease and clinical signs of perianal inflammatory disease. Within a median of 10 d (range 0-75) these patients underwent MRI of the pelvis. Regular convex and linear high resolution probes were used for PAUS. The sonographic findings were correlated to the MRI findings by blinded investigators. RESULTS: The sonographic investigations were well tolerated by all patients. Fistulae typically presented as hypoechoic tracks. Twenty-nine fistulae were detected in 22 patients. Abscesses were detected in 7 patients and presented as hypo- or anechoic formations. Twenty-six of 29 fistulae and 6 of 7 abscesses could be confirmed by MRI. Kappa statistics showed an excellent agreement (kappa>0.83) between the two imaging methods. CONCLUSION: PAUS is a simple, painless, feasible, real-time method that can be performed without specific patient preparation which is comparable in its sensitivity to pelvic MRI in the detection of perianal fistulae and/or abscesses. PAUS can especially be recommended as a screening tool in acute perianal disorders such as perianal abscess and for follow-up studies of perianal inflammatory disease.


Assuntos
Canal Anal/anatomia & histologia , Doenças do Ânus/diagnóstico por imagem , Doença de Crohn/diagnóstico por imagem , Inflamação/diagnóstico por imagem , Canal Anal/diagnóstico por imagem , Humanos , Ultrassonografia Doppler em Cores/instrumentação , Ultrassonografia Doppler em Cores/métodos
20.
Hepat Mon ; 13(1): e6003, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23483295

RESUMO

BACKGROUND: Biliary complications are significant source of morbidity after liver transplantation (LT). Cholangiography is the gold standard for diagnosis and specification of biliary complications. OBJECTIVES: Detailed analyses of ultrasound (US) as a safe imaging method in this regard are still lacking. Therefore we analyzed systematically the diagnostic value of US in these patients. PATIENTS AND METHODS: Retrospectively, 128 liver graft recipients and their clinical data were analyzed. All patients had a standardized US examination. The findings of US were compared to cholangiographic results in 42 patients. Following statistical analyses were performed: descriptive statistics, sensitivity, specificity, positive and negative predictive values (PPV, NPV). RESULTS: 42 patients had 54 different biliary complications (Anastomotic stenosis (AS) n = 33, ischemic type biliary lesions (ITBL) n = 18 and leakage n = 3). US detected n = 22/42 (52%) patients with biliary complications. The sensitivity, specificity, PPV and NPV of US were: 61%, 100%, 100%, 79% (95CI, 36-86%) for ITBL and 24%, 100, 100%, 31% (95CI, 9-46 %) for AS, respectively. CONCLUSIONS: US examination had no false positive rate. Therefore, it may be helpful as a first screening modality. But for the direct diagnosis of the biliary complication US is not sensitive enough.

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