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Dive into the research topics where André Siqueira Matheus is active.

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Featured researches published by André Siqueira Matheus.


Pancreas | 2006

Local and systemic effects of hypertonic solution (NaCl 7.5%) in experimental acute pancreatitis.

Marcel Cerqueira Cesar Machado; Ana Maria M. Coelho; Vera Pontieri; Sandra N. Sampietre; Nilza Aparecida Trindade Molan; Francisco Garcia Soriano; André Siqueira Matheus; Rosely A. Patzina; José Eduardo M. Cunha; Irineu Tadeu Velasco

Objectives: Severe acute pancreatitis (AP) is characterized by hemodynamic alterations and a systemic inflammatory response, leading to a high mortality rate. Treatment of hemorrhagic shock with hypertonic saline solutions significantly reduces mortality through an improvement in the hemodynamic conditions and possibly by an anti-inflammatory effect. Therefore, hypertonic solutions could be effective in AP. Methods: Wistar rats were divided in 4 groups: group C, control, without AP; group NT, AP, without treatment; group NS, treatment with normal saline solution (NaCl 0.9%) 1 hour after AP; group HTS, treatment with hypertonic saline solution (NaCl 7.5%) 1 hour after AP. AP was induced by injection of 2.5% sodium taurocholate into the pancreatic duct. Mean arterial blood pressure (MAP) and heart rate were recorded at 0 and 2, 4, 24, and 48 hours after AP. After induction of AP, animals were killed at 2, 12, 24, and 48 hours for serum amylase, interleukin (IL)-6, and IL-10 analysis, pancreatic tissue culture and histologic analysis, oxidation and phosphorylation of liver mitochondria, pulmonary myeloperoxidase activity (MPO), and mortality study. Results: In animals of groups NS and NT, a significant decrease of MAP was observed 48 hours after AP (NS: 91 ± 3 mm Hg; NT: 89 ± 3 mm Hg) compared with baseline (C: 105 ± 2 mm Hg) and to HTS group (HTS: 102 ± 2 mm Hg; P < 0.05). In animals of group NT, NS, and HTS, serum IL-6 and IL-10 levels were significantly higher at 2 hours after AP compared with the control group. However, IL-6 levels at 12 hours after AP and IL-10 levels at 2 and 12 hours after AP were significant lower in group HTS compared with NS and NT groups (P < 0.05). In group HTS, a decrease of pulmonary MPO activity and of pancreatic infection was observed 24 hours after AP compared with NT and NS groups (P < 0.05). A significant reduction on pancreatic acinar necrosis and mitochondrial dysfunction was observed after 48 hours of AP in animals of group HTS compared with groups NT and NS (P < 0.05). A significant reduction on mortality was observed in HTS (0/14) compared with NS (6/17; 35%) and NT (7/20; 35%). Conclusions: The administration of hypertonic saline solution in experimental AP attenuated hemodynamic alterations, decreased inflammatory cytokines, diminished systemic lesions and pancreatic acinar necrosis, prevented pancreatic infection, and reduced the mortality rate.


Hpb | 2007

Effect of inhibition of prostaglandin E2 production on pancreatic infection in experimental acute pancreatitis

André Siqueira Matheus; Ana Maria M. Coelho; Sandra N. Sampietre; Rosely A. Patzina; José Eduardo M. Cunha; Marcel Cerqueira Cesar Machado

OBJECTIVE Acute pancreatitis is one the important causes of systemic inflammatory response syndrome (SIRS). SIRS results in gut barrier dysfunction that allows bacterial translocation and pancreatic infection to occur. Indomethacin has been used to reduce inflammatory process and bacterial translocation in experimental models. The purpose of this study was to determine the effect of inhibition of prostaglandin E2 (PGE2) production on pancreatic infection. MATERIALS AND METHODS An experimental model of severe acute pancreatitis (AP) was utilized. The animals were divided into three groups: sham (surgical procedure without AP induction); pancreatitis (AP induction); and indomethacin (AP induction plus administration of 3 mg/kg of indomethacin). Serum levels of interleukin (IL)-6 and IL-10, PGE2, and tumor necrosis factor (TNF)-alpha were measured 2 h after the induction of AP. We analyzed the occurrence of pancreatic infection with bacterial cultures performed 24 h after the induction of AP. The occurrence of pancreatic infection (considered positive when the CFU/g was >105), pancreatic histologic analysis, and mortality rate were studied. RESULTS In spite of the reduction of IL-6, IL-10, and PGE2 levels in the indomethacin group, TNF-alpha level, bacterial translocation, and pancreatic infection were not influenced by administration of indomethacin. The inhibition of PGE2 production did not reduce pancreatic infection, histologic score, or mortality rate. CONCLUSION The inhibition of PGE2 production was not able to reduce the occurrence of pancreatic infection and does not have any beneficial effect in this experimental model. Further investigations will be necessary to discover a specific inhibitor that would make it possible to develop an anti-inflammatory therapy.


Pancreatology | 2009

Do the Effects of Pentoxifylline on the Inflammatory Process and Pancreatic Infection Justify Its Use in Acute Pancreatitis

André Siqueira Matheus; Ana Maria M. Coelho; Sandra N. Sampietre; Rosely A. Patzina; José Eduardo M. Cunha; Marcel Cerqueira Cesar Machado

Severe acute pancreatitis is associated with high morbidity and mortality rates. At the present time, no specific therapy has been shown to be uniformly effective in reducing morbidity and mortality in this disease. The aim of this study was to determine the effects of pentoxifylline on the pancreatic and systemic inflammatory process, pancreatic infection, and mortality rate in severe acute pancreatitis in rats. Methods: One hundred and twenty male Wistar rats were divided into 3 groups: sham, pancreatitis, and pentoxifylline (acute pancreatitis induction plus administration of 25 mg/kg pentoxifylline). Inflammatory response was measured by histological studies, inflammatory cytokine production (IL-6, IL-10, and TNF-α), and mortality rate. Pancreatic infection was evaluated by bacterial cultures expressed in colony-forming units per gram. Results: Pentoxifylline-treated animals had a statistically significant reduction of inflammatory cytokine levels, pancreatic histological damage, occurrence of bacterial translocation and pancreatic infection (p < 0.05), associated with a significant reduction in mortality rate. Conclusions: Pentoxifylline administration in this experimental model of acute pancreatitis reduces local and systemic inflammatory responses and decreases the pancreatic infection and the mortality rate.


Clinics | 2010

CHOLELITHIASIS IN PATIENTS ON THE KIDNEY TRANSPLANT WAITING LIST

André Thiago Scandiuzzi Brito; Luiz S. Azevedo; Willian Nahas; André Siqueira Matheus

OBJECTIVES To evaluate the prevalence of cholecystopathy in chronic renal patients awaiting kidney transplants. INTRODUCTION The prevalence and management of cholelithiasis in renal transplant patients is not well established. METHODS A total of 342 chronic renal failure patients on the waiting list for a kidney transplant were studied. Patients were evaluated for the presence of cholelithiasis and related symptoms, previous cholecystectomies and other abdominal surgeries, time on dialysis, and general data (gender, age, number of pregnancies, and body mass index). RESULTS Cholelithiasis was found in 41 out of 342 patients (12%). Twelve of these patients, all symptomatic, had previously undergone cholecystectomies. Five out of 29 patients who had not undergone surgery were symptomatic. Overall, 17 patients (41.5%) were symptomatic. Their mean age was 54 (range 32–74) years old; 61% were female, and their mean body mass index was 25.4. Nineteen (76%) out of 25 women had previously been pregnant, with an average of 3.6 pregnancies per woman. CONCLUSIONS The frequency of cholelithiasis was similar to that reported in the literature for the general population. However, the high frequency of symptomatic patients points toward an indication of routine pre-transplant cholecystectomy to avoid serious post-transplant complications.


Journal of Gastrointestinal Surgery | 2008

Synchronous Adenocarcinoma of the Major and Minor Duodenal Papilla

André Siqueira Matheus; André Luis Montagnini; Tiago Kunitake; Rosely A. Patzina; José Eduardo M. Cunha


in Vivo | 2005

Suppression of invasion of a hamster pancreatic cancer cell line by antisense oligonucleotides mutation-matched to K-ras gene.

Cintia Yoko Morioka; Marcel Cerqueira Cesar Machado; Seiji Saito; Yuji Nakada; André Siqueira Matheus; Telesforo Bacchella; Terumi Takahara; Akiharu Watanabe


Pancreas | 2004

PENTOXIFYLLINE REDUCE INFLAMMATORY MEDIATORS LEVELS AND MORTALITY RATE IN AN EXPERIMENTAL ACUTE PANCREATITIS MODEL.

André Siqueira Matheus; Ana Maria M. Coelho; Sandra N. Sampietre; C.Y. Morioka; J.E.M. Cunha; Marcel Cerqueira Cesar Machado


Pancreas | 2004

K-RAS POINT MUTATION DETECTION BY PCR/RFLP ANALYSIS VERSUS HISTOPATHOLOGY IN HAMSTER EXPERIMENTAL PANCREATIC CANCER MODEL—WHICH SENSITIVITY IS HIGHER IN DETECTION OF METASTASES?

C.Y. Morioka; Marcel Cerqueira Cesar Machado; Seiji Saito; André Siqueira Matheus; R.S. Godoy; Márcia Saldanha Kubrusly; T. Bacchella; K. Kita; Akiharu Watanabe


Journal of Gastrointestinal Surgery | 2005

Effect of inhibition of TNF-α in experimental acute pancreatitis: A study of systemic inflammatory process, pancreatic infection, and mortality rate

André Siqueira Matheus; Ana Maria M. Coelho; Cintia Yoko Morioka; Sandra N. Sampietre; José Eduardo M. Cunha; Marcel Cerqueira Cesar Machado


Journal of Immunology | 2011

Dendritic cell generation from PBMC obtained from jaundiced patients with pancreatic adenocarcinoma -- a potential role for STAT-1?

Joao Paulo do Carmo; Marisa Treglia; André Siqueira Matheus; Joaquim Jose Rodrigues; Jose Eduardo da Cunha; Marcel Cerqueira Cesar Machado; Patrícia Cruz Bergami-Santos; José Alexandre Marzagão Barbuto

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Akiharu Watanabe

Kawasaki University of Medical Welfare

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