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Featured researches published by Aytan M. Sipahi.


Brazilian Journal of Medical and Biological Research | 2003

Lack of evidence for the pathogenic role of iron and HFE gene mutations in Brazilian patients with nonalcoholic steatohepatitis

M.M. Deguti; Aytan M. Sipahi; L.C.C. Gayotto; Selma A. Palácios; Paulo Lisboa Bittencourt; Anna Carla Goldberg; Antonio Atilio Laudanna; Flair José Carrilho; Eduardo Luiz Rachid Cançado

The hypothesis of the role of iron overload associated with HFE gene mutations in the pathogenesis of nonalcoholic steatohepatitis (NASH) has been raised in recent years. In the present study, biochemical and histopathological evidence of iron overload and HFE mutations was investigated in NASH patients. Thirty-two NASH patients, 19 females (59%), average 49.2 years, 72% Caucasians, 12% Mulattoes and 12% Asians, were submitted to serum aminotransferase and iron profile determinations. Liver biopsies were analyzed for necroinflammatory activity, architectural damage and iron deposition. In 31 of the patients, C282Y and H63D mutations were tested by PCR-RFLP. Alanine aminotransferase levels were increased in 30 patients, 2.42 1.12 times the upper normal limit on average. Serum iron concentration, transferrin saturation and ferritin averages were 99.4 31.3 g/dl, 33.1 12.7% and 219.8 163.8 g/dl, respectively, corresponding to normal values in 93.5, 68.7 and 78.1% of the patients. Hepatic siderosis was observed in three patients and was not associated with architectural damage (P = 0.53) or with necroinflammatory activity (P = 0.27). The allelic frequencies (N = 31) found were 1.6 and 14.1% for C282Y and H63D, respectively, which were compatible with those described for the local population. In conclusion, no evidence of an association of hepatic iron overload and HFE mutations with NASH was found. Brazilian NASH patients comprise a heterogeneous group with many associated conditions such as hyperinsulinism, environmental hepatotoxin exposure and drugs, but not hepatic iron overload, and their disease susceptibility could be related to genetic and environmental features other than HFE mutations.


Digestive Diseases and Sciences | 2004

Ursodeoxycholic acid ameliorates experimental ileitis counteracting intestinal barrier dysfunction and oxidative stress.

Carlos Felipe Bernardes-Silva; Aderson Omar Mourão Cintra Damião; Aytan M. Sipahi; Francisco R.M. Laurindo; Kiyoshi Iriya; Fábio Pinatel Lopasso; Carlos Alberto Buchpiguel; Maria Laura Lacava Lordello; Carmem L. O. Agostinho; Antonio Atilio Laudanna

The aim of this study was to evaluate the effect of ursodeoxycholic acid (UDCA) on intestinal permeability (IP) and reactive oxygen species (ROS) generation in indomethacin-induced enteropathy, a well-known experimental model of Crohns disease. Seventy-eight male Wistar rats were randomly assigned to receive indomethacin, indomethacin + UDCA, or vehicles. Indomethacin induced a significant increase in the fraction of urinary excretion of 51Cr-EDTA following oral administration (7.9 ± 1.3 vs 2.3 ± 0.2%; P < 0.05) and lucigenin-amplified chemiluminescence in intestinal fragments ex vivo (10.1 ± 1.9 vs 2.6 ± 0.4 cpm × 103/mg; P < 0.05) compared to controls. UDCA significantly reversed these effects (P < 0.05), without being incorporated in biliary bile acid composition (HPLC analysis). These findings support a local protective effect of UDCA in experimental ileitis by the modulation of intestinal barrier dysfunction and oxidative stress. In short, they provide insights into mechanisms of action of UDCA in intestinal inflammation and a new perspective on the treatment of Crohns disease.


Digestion | 1997

Gallbladder Hypokinesia in Crohn’s Disease

Aderson Omar Mourão Cintra Damião; Aytan M. Sipahi; Denise P. Vezozzo; Patricia Lofego Goncalves; Pedro Fukui; Antonio Atilio Laudanna

For the purpose of shedding some light upon the possible mechanisms involved in gallstone formation in patients with Crohns disease, we have investigated gallbladder emptying by means of ultrasonography in two groups of subjects: controls (n = 40) and Crohns disease (n = 30). Diminished gallbladder emptying after a liquid fatty-meal stimulus was observed in patients with Crohns disease when compared with controls (p < 0.001). Also, the values for the residual gallbladder volume (RGV) and maximal decrease in gallbladder volume (MDGV), both in milliliters and percentage were, respectively, increased (RGV = 9.6 ml) and diminished (MDGV = 14.8 ml; MDGV = 60.9%) in patients with Crohns disease when compared with controls (RGV = 5.9 ml, p < 0.001; MDGV = 19.9 ml, p = 0.003; MDGV = 77.8%, p < 0.001). Hence, reduced gallbladder emptying with consequent stasis might be a contributory factor to the increased prevalence of gallstones in Crohns disease.


Clinics | 2012

Prevalence of celiac disease among blood donors in São Paulo: the most populated city in Brazil

Marília Lage Alencar; Carmen Lucia Ortiz-Agostinho; lêda Nishitokukado; Aderson Omar Mourão Cintra Damião; Clarice Pires Abrantes-Lemos; André Zonetti de Arruda Leite; Thales de Brito; Dalton de Alencar Fischer Chamone; Maria Elizabeth Rossi da Silva; Daniel Giannella-Neto; Aytan M. Sipahi

OBJECTIVE: Celiac disease is a permanent enteropathy caused by the ingestion of gluten, which leads to an immune-mediated inflammation of the small intestine mucosa. The prevalence of celiac disease varies among different nations and ethnic backgrounds, and its diversity is determined by genetic and environmental factors. São Paulo city is one of the largest cities in the world, with a vast population and an important history of internal migratory flow from other Brazilian regions, as well as immigration from other, primarily European, countries, resulting in significant miscegenation. The aim of the present study was to estimate the prevalence of adults with undiagnosed celiac disease among blood donors of São Paulo by collecting information on the ancestry of the population studied. METHODS: The prevalence of celiac disease was assessed by screening for positive IgA transglutaminase and IgA endomysium antibodies in 4,000 donors (volunteers) in the Fundação Pró-Sangue Blood Center of São Paulo, São Paulo, Brazil. The antibody-positive subjects were asked to undergo a small bowel biopsy. RESULTS: Of the 4,000 subjects, twenty-four had positive tests, although both antibody tests were not always concordant. For example, ten subjects were positive for IgA tissue transglutaminase only. In twenty-one positive patients, duodenal biopsies were performed, and the diagnosis of celiac disease was confirmed in fourteen patients (Marsh criteria modified by Oberhuber). In this group, 67% claimed to have European ancestry, mainly from Italy, Portugal and Spain. CONCLUSION: The prevalence of celiac disease is at least 1:286 among supposedly healthy blood bank volunteers in São Paulo, Brazil.


Jornal De Pediatria | 2013

Clinical manifestations, treatment, and outcomes of children and adolescents with eosinophilic esophagitis

Maraci Rodrigues; Maria Fernanda M. D’Amico; Fatima Regina Almeida Patiño; Dorina Barbieri; Aderson Omar Mourão Cintra Damião; Aytan M. Sipahi

Objective This study aimed to describe the clinical, endoscopic, and histologic characteristics, as well as the response to conventional treatment of pediatric patients with the classical form of eosinophilic esophagitis (EoE).OBJECTIVE This study aimed to describe the clinical, endoscopic, and histologic characteristics, as well as the response to conventional treatment of pediatric patients with the classical form of eosinophilic esophagitis (EoE). METHODS Study of clinical, laboratory, endoscopic, and histologic data and response to conventional treatment of 43 previously followed pediatric patients with the classical form of EoE. RESULTS A total of 43 patients diagnosed with EoE were included in the study, of which 37 were males (86%), with a mean age of 8.4 years. The most common symptoms were: nausea, vomiting, and abdominal pain (100%) in children younger than 7 years, and loss of appetite (60%), heartburn (52%), and food impaction (48%) in children older than 7 years and adolescents. Regarding the endoscopic findings, 12 (28%) patients had whitish plaques on the esophageal lining, 8 (18.5%) had longitudinal grooves, 2 (4.5%) had concentric rings, 3 (7%) had longitudinal grooves and whitish plaques, and the remaining 18 (42%) had esophageal mucosa with normal appearance. Despite the initial favorable response, 76.7% of patients required more than one course of corticosteroid therapy (systemic or aerosol) and diet (exclusion or elimination of food or elementary allergens). Persistence of eosinophil infiltration was found in some patients despite favorable clinical response. CONCLUSIONS The classic form of EoE typically shows different symptoms according age range. A significant number of patients required more than one treatment cycle to show clinical remission. Endoscopic and histologic improvement was observed; however, eosinophilic infiltration persisted in some patients.


Jornal De Pediatria | 2013

Original ArticleClinical manifestations, treatment, and outcomes of children and adolescents with eosinophilic esophagitisManifestações clínicas, terapêutica e evolução de crianças e adolescentes com eso- fagite eosinofílica*

Maraci Rodrigues; Maria Fernanda M. D’Amico; Fatima Regina Almeida Patiño; Dorina Barbieri; Aderson Omar Mourão Cintra Damião; Aytan M. Sipahi

Objective This study aimed to describe the clinical, endoscopic, and histologic characteristics, as well as the response to conventional treatment of pediatric patients with the classical form of eosinophilic esophagitis (EoE).OBJECTIVE This study aimed to describe the clinical, endoscopic, and histologic characteristics, as well as the response to conventional treatment of pediatric patients with the classical form of eosinophilic esophagitis (EoE). METHODS Study of clinical, laboratory, endoscopic, and histologic data and response to conventional treatment of 43 previously followed pediatric patients with the classical form of EoE. RESULTS A total of 43 patients diagnosed with EoE were included in the study, of which 37 were males (86%), with a mean age of 8.4 years. The most common symptoms were: nausea, vomiting, and abdominal pain (100%) in children younger than 7 years, and loss of appetite (60%), heartburn (52%), and food impaction (48%) in children older than 7 years and adolescents. Regarding the endoscopic findings, 12 (28%) patients had whitish plaques on the esophageal lining, 8 (18.5%) had longitudinal grooves, 2 (4.5%) had concentric rings, 3 (7%) had longitudinal grooves and whitish plaques, and the remaining 18 (42%) had esophageal mucosa with normal appearance. Despite the initial favorable response, 76.7% of patients required more than one course of corticosteroid therapy (systemic or aerosol) and diet (exclusion or elimination of food or elementary allergens). Persistence of eosinophil infiltration was found in some patients despite favorable clinical response. CONCLUSIONS The classic form of EoE typically shows different symptoms according age range. A significant number of patients required more than one treatment cycle to show clinical remission. Endoscopic and histologic improvement was observed; however, eosinophilic infiltration persisted in some patients.


PLOS ONE | 2014

Cytomegalovirus Infection in Inflammatory Bowel Disease Is Not Associated with Worsening of Intestinal Inflammatory Activity

Alexandre Medeiros do Carmo; Fabiana M. Santos; Carmen Lucia Ortiz-Agostinho; Iêda Nishitokukado; Cintia S. Frota; Flavia Ubeda Gomes; André Zonetti de Arruda Leite; Cláudio Sérgio Pannuti; Lucy S. Vilas Boas; Magaly Gemio Teixeira; Aytan M. Sipahi

Background Cytomegalovirus is highly prevalent virus and usually occurs in immunocompromised patients. The pathophysiology and treatment of inflammatory bowel disease often induce a state of immunosuppression. Because this, there are still doubts and controversies about the relationship between inflammatory bowel disease and cytomegalovirus. Aim Evaluate the frequency of cytomegalovirus in patients with inflammatory bowel disease and identify correlations. Methods Patients with inflammatory bowel disease underwent an interview, review of records and collection of blood and fecal samples. The search for cytomegalovirus was performed by IgG and IgM blood serology, by real-time PCR in the blood and by qualitative PCR in feces. Results were correlated with red blood cell levels, C-reactive protein levels, erythrocyte sedimentation rates and fecal calprotectin levels for each patient. Results Among the 400 eligible patients, 249 had Crohns disease, and 151 had ulcerative colitis. In the group of Crohns disease, 67 of the patients had moderate or severe disease, but 126 patients presented with active disease, based on the evaluation of the fecal calprotectin. In patients with ulcerative colitis, only 21 patients had moderate disease, but 76 patients presented with active disease, based on the evaluation of the fecal calprotectin. A large majority of patients had positive CMV IgG. Overall, 10 patients had positive CMV IgM, and 9 patients had a positive qualitative detection of CMV DNA by PCR in the feces. All 400 patients returned negative results after the quantitative detection of CMV DNA in blood by real-time PCR. Analyzing the 19 patients with active infections, we only found that such an association occurred with the use of combined therapy (anti-TNF-alpha + azathioprine) Conclusion The findings show that latent cytomegalovirus infections are frequent and active cytomegalovirus infection is rare. We did not find any association between an active infection of CMV and inflammatory bowel disease activity.


Brazilian Journal of Medical and Biological Research | 2004

Effect of a selective nonsteroidal anti-inflammatory inhibitor of cyclooxygenase-2 on the small bowel of rats

A.Z.A. Leite; Aytan M. Sipahi; Aderson Omar Mourão Cintra Damião; A.T. Garcez; Carlos Alberto Buchpiguel; Fábio Pinatel Lopasso; Maria Laura Lacava Lordello; C.L.O. Agostinho; Antonio Atilio Laudanna

The pathogenesis of nonsteroidal anti-inflammatory drug (NSAID) enteropathy is a complex process involving the uncoupling of mitochondrial oxidative phosphorylation and inhibition of cyclooxygenase (COX). Rofecoxib, a selective inhibitor of COX-2, has shown less gastric damage, but the same beneficial effect is not clear in the case of the small bowel. Fifty-seven male Wistar rats (250-350 g) were divided into three groups (N=19 each) to evaluate the effect of this NSAID on the rat intestine. The groups received 2.5 mg/kg rofecoxib, 7.5 mg/kg indomethacin or water with 5% DMSO (control) given as a single dose by gavage 24 h before the beginning of the experiment. A macroscopic score was used to quantify intestinal lesions and intestinal permeability was measured using [51Cr]-ethylenediaminetetraacetic acid ([51Cr]-EDTA). The extent of intestinal lesion, indicated by a macroscopic score, was significantly lower when rofecoxib was administered compared to indomethacin (rofecoxib=0.0 vs indomethacin=63.6 +/- 25.9; P<0.05) and did not differ from control. The intestinal permeability to [51Cr]-EDTA was significantly increased after indomethacin (control=1.82 +/- 0.4 vs indomethacin=9.12 +/- 0.8%; P<0.0001), but not after rofecoxib, whose effect did not differ significantly from control (control=1.82 +/- 0.4 vs rofecoxib=2.17 +/- 0.4%; ns), but was significantly different from indomethacin (indomethacin=9.12 +/- 0.8 vs rofecoxib=2.17 +/- 0.4%; P<0.001). In conclusion, the present data show that rofecoxib is safer than indomethacin in rats because it does not induce macroscopic intestinal damage or increased intestinal permeability.


Brazilian Journal of Medical and Biological Research | 2001

Intestinal permeability in strongyloidiasis.

A.L. Werneck-Silva; Aytan M. Sipahi; Aderson Omar Mourão Cintra Damião; C.A. Buchpigue; Kiyoshi Iriya; Antonio Atilio Laudanna

Abstract The objective of the present study was to assess intestinal permeabilityin patients with infection caused by Strongyloides stercoralis . Twenty-six patients (16 women and 10 men), mean age 45.9, with a diagnosisof strongyloidiasis were evaluated. For comparison, 25 healthy volun-teers (18 women and 7 men), mean age 44.9, without digestivedisorders or intestinal parasites served as normal controls. Intestinalpermeability was measured on the basis of urinary radioactivity levelsduring the 24 h following oral administration of chromium-labeledethylenediaminetetraacetic acid ( 51 Cr-EDTA) expressed as percent-age of the ingested dose. The urinary excretion of 51 Cr-EDTA wassignificantly reduced in patients with strongyloidiasis compared tocontrols (1.60 – 0.74 and 3.10 – 1.40, respectively, P = 0.0001).Intestinal permeability is diminished in strongyloidiasis. Abnormali-ties in mucus secretion and intestinal motility and loss of macromol-ecules could explain the impaired intestinal permeability.


Digestive Diseases and Sciences | 1997

Effects of Colectomy on Gallbladder Motility in Patients with Ulcerative Colitis

Aderson Omar Mourão Cintra Damião; Aytan M. Sipahi; Denise P. Vezozzo; Patricia Lofego Goncalves; Angelita Habr-Gama; Magaly Gemio Teixeira; Julia T. Fukushima; Antonio Atilio Laudanna

In order to gain insight into the possiblemechanisms involved in gallstone formation incolectomized ulcerative colitis patients, we studiedgallbladder motility by means of ultrasonography inthree groups of subjects: controls (N = 40) and ulcerativecolitis patients without (N = 30) and with (N = 20)colectomy. Impaired gallbladder emptying after a liquidfatty meal stimulus was observed in ulcerative colitis patients with colectomy compared with thoseobtained in ulcerative colitis patients withoutcolectomy and controls (P = 0.001). The maximumpercentage of gallbladder emptying also, wassignificantly lower (59.8%) than those seen in ulcerative colitispatients without colectomy (74.5%) and controls (77.8%)(P = 0.001). Diminished gallbladder emptying withensuing stasis might be a contributory factor to the increased prevalence of gallstones incolectomized patients.

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André Z. Leite

Case Western Reserve University

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