Bruno Zilberstein

Bacterial translocation: Overview of mechanisms and clinical impact

Bacterial translocation (BT) is a phenomenon in which live bacteria or its products cross the intestinal barrier. Gut translocation of bacteria has been shown in both animal and human studies. BT and its complications have been shown clearly to occur in animal models, but its existence and importance in humans has been difficult to ascertain. We review the mechanisms of BT and its clinical impact based on the current literature.

Prevalence of Subclinical Hypothyroidism in a Morbidly Obese Population and Improvement after Weight Loss Induced by Roux-en-Y Gastric Bypass

Background:There are many studies concerning thyroid function in obesity, and some of them describe higher TSH levels in obese subjects. Few studies evaluated long-term changes in thyroid function caused by weight loss after bariatric surgery. Our aims were to evaluate the prevalence of subclinical hypothyroidism (SH) in a morbidly obese population and to analyze the effect of weight loss induced by Roux-en-Y gastric bypass (RYGBP) on TSH and thyroid hormone (TH) levels. Methods: TSH, free thyroxine (fT4) and total triiodothyronine (T3) levels were analyzed before and 12 months after RYGBP in patients with grade III or grade II obesity with co-morbidities. Subjects taking TH and/or with positive antithyroid antibodies and/or with overt hypothyroidism were excluded. Results: 72 subjects (62F/10M), with mean age 39.6±9.8 years and mean BMI 53.0±10.4 kg/m2 were studied. The prevalence of SH before RYGBP was 25% (n=18). There was a significant post-surgical decrease in BMI in the whole population, as well as in SH patients. In the SH group and normal TSH group, there was a decrease in TSH and T3, but not in fT4. TSH was not correlated with initial BMI or percent change in BMI. TSH concentrations reached normal values in all SH patients after RYGBP. Conclusion: Our data confirm that severe obesity is associated with increased TSH. The decrease in TSH was independent of BMI, but occurred in all SH patients. A putative effect of weight reduction on the improvement of SH in all patients may be an additional benefit of bariatric surgery.

The prognostic value of CD147/EMMPRIN is associated with monocarboxylate transporter 1 co-expression in gastric cancer

The aim of the present work was to assess the role of monocarboxylate transporters (MCTs), namely MCT1 and MCT4 as well as MCT/CD147 co-expression in gastric tissues and evaluate their clinico-pathological significance in gastric carcinoma. For that, we analysed the immunohistochemical expression of MCT1, MCT4 and CD147, in a large series of gastric samples, including non-neoplastic, tumour and metastatic tissues. A significant decrease in MCT4 plasma membrane expression was observed from non-neoplastic to gastric primary malignant tissues and to lymph-node metastasis and both MCT1 and MCT4 correlated with CD147. Importantly, both MCT4 and CD147 were more frequently expressed in Laurens intestinal-type tumours and MCT1/CD147 co-expression was associated with advanced gastric carcinoma, Laurens intestinal type, TNM staging and lymph-node metastasis. Our results showed that the prognostic value of CD147 was associated with MCT1 co-expression in gastric cancer cells, supporting the view that CD147 plasma membrane activity is dependent on MCT co-expression.

Does the intraoperative peritoneal lavage cytology add prognostic information in patients with potentially curative gastric resection

Peritoneal recurrence is the foremost pattern of failure after potentially curative resection for gastric cancer. Our aim was to evaluate the prognostic value of intraperitoneal free cancer cells (IFCCs) in peritoneal lavage of patients who underwent potentially curative resection for gastric carcinoma. Two hundred twenty patients with gastric cancer stage I, II, or III were prospectively evaluated with peritoneal lavage and cytologic examination. Aspirated fluid from the abdominal cavity was centrifuged and subjected to Papanicolaou staining. The mean age was 60.9 years (range, 21–89 years), and 63.6% were men. IFCCs were detected in 6.8% of the patients; suspicious in 2.7%, and negative in 84.5%. No judgment could be given in 5.9% of the cases. Invasion of the gastric serosa (pT3) was observed in all positive cytology patients. Patients with IFCCs had a mean survival time of 10.5 months, while those with negative IFCC had a mean survival time of 61 months (P = 0.00001). There was no correlation between the presence of IFCCs and tumor size, histology, pN, or tumor site. Our conclusions are that (1) positive cytology indicates a poor prognosis in patients who underwent potentially curative gastric resection and (2) peritoneal lavage cytology improves staging in assessing these patients and may alter their therapeutic approach.

Dietary intake of female bariatric patients after anti-obesity gastroplasty

PURPOSE Roux-en-Y gastric bypass is a popular and successful operation for the treatment of morbid obesity. However, it greatly restricts ingestion and moderately interferes with absorption of food, thus potentially paving the way for undernutrition, especially during the first year before patients adapt to the new condition. Aiming to document actual dietary intake during this period, a prospective observational study was performed. METHODS Forty consecutive patients were investigated using a 24-hour dietary recall technique every 3 months after surgery for 1 year. Females only were accepted for greater homogeneity of the sample. All received a vitamin and mineral supplement on a daily basis as a postoperative routine. A questionnaire was employed regarding general, nutritional, and gastrointestinal changes as well as consumption of medications. Dietary intake was analyzed after data processing using the Virtual Nutri software package (São Paulo, SP, Brazil). RESULTS The surgical response was within the expected range, with about 67% excess weight loss at the end of the 1st year, and the same occurred with gastrointestinal symptoms and drug requirements. Daily energy intake on the 4 analyzed occasions was 529.4 +/- 47.4, 710.9 +/- 47.6, 833.2 +/- 72.0, and 866.2 +/- 95,1 kcal/day (mean +/- SEM); protein intake was increased in the same proportion at 6 and 9 months, but reduced at 12 months. Thus, patients did not meet standard recommendations regarding calories and proteins, even at the end of the 1st year; iron and zinc intake were also inadequate, although deficiencies were probably staved off by the prescribed supplement preparation. CONCLUSIONS 1) The risk for postoperative undernutrition was evidenced up to 1 year, while spontaneous improvement in food intake was slow and inefficient; 2) Specific protocols should be devised to improve nutrition and health during the postoperative phase until successful dietary adaptation is achieved.

Óxido nítrico: o simples mensageiro percorrendo a complexidade. Metabolismo, síntese e funções.

Vamos supor que apos ler este artigo, voce guar-de na sua memoria tardia uma parte do que leu.Provavelmente voce estara utilizando para istouma das menores e mais versateis moleculas doseu organismo: o oxido nitrico (NO - Nitric Oxide).Esta pequena e simples molecula, talvez a menorproduzida pelos mamiferos, tem efeitos fascinan-tes desde a manutencao inicial da vida, atraves docontrole da circulacao placentaria, ou a inducao doinicio da vida atraves da regulagem das contracoesuterinas no trabalho de parto, como tambem efei-tos letais demonstraveis, por exemplo, no choqueseptico. O oxido nitrico e um importante neuro-transmissor com capacidade potencializadora,atuando na memoria e no aprendizado, podendotambem ter acoes endocrinas, autocrinas e para-crinas. A sua acao na imuno-regulacao esta pre-sente na inflamacao e nos mecanismos de autoi-munidade. Esta molecula tem revolucionado eobrigado revisao de paradigmas da medicina, prin-cipalmente em neurologia, cardiologia, nefrologiae gastroenterologia.Este artigo procura mostrar os mecanismos desintese e formacao do oxido nitrico apresentando aenzima envolvida - sintase do oxido nitrico (nitricoxide synthase - NOS) e os efeitos do NO comomensageiro nos principais sistemas do organismo.

Lipid Peroxidation in Bariatric Candidates with Nonalcoholic Fatty Liver Disease (NAFLD) – Preliminary Findings

Background: Pathogenesis of nonalcoholic fatty liver disease (NAFLD) remains incompletely known, and oxidative stress is one of the mechanisms incriminated. The aim of this study was to evaluate the role of liver oxidative stress in NAFLD affecting morbidly obese patients. Methods: 39 consecutive patients with BMI >40 kg/m2 submitted to Roux-en-Y gastric bypass were enrolled, and wedge liver biopsy was obtained during operation. Oxidative stress was measured by concentration of hydroperoxides (CEOOH) in liver tissue. Results: Female gender was dominant (89.7%) and median age was 43.6 ± 11.1 years. Histology showed fatty liver in 92.3%, including 43.6% with nonalcoholic steatohepatitis (NASH), 48.7% with isolated steatosis and just 7.7% with normal liver. Liver cirrhosis was present in 11.7% of those with nonalcoholic steatohepatitis. Concentration of CEOOH was increased in the liver of patients with NASH when compared to isolated steatosis and normal liver (0.26± 0.17, 0.20± 0.01 and 0.14± 0.00 nmol/mg protein, respectively) (P <0.01). Liver biochemical variables were normal in 92.3% of all cases, and no difference between NASH and isolated steatosis could be demonstrated. Conclusions: 1) Nonalcoholic steatosis, steatohepatitis and cirrhosis were identified in substantial numbers of morbidly obese patients; 2) Concentration of hydroperoxides was increased in steatohepatitis, consistent with a pathogenetic role for oxidative stress in this condition.

Topiramate after Adjustable Gastric Banding in Patients with Binge Eating and Difficulty Losing Weight

Background: About 15% of patients who undergo adjustable gastric banding (AGB) have difficulty losing weight due to, among other factors, the development or maintenance of binge eating disorder. Topiramate is an anticonvulsive drug with proven good results in controlling binge eating episodes. The objective of this study was to analyze the effect of topiramate in patients with AGB. Methods: 16 patients with binge eating and inadequate weight loss after AGB were analyzed prospectively for 3 months while receiving topiramate in doses varying from 12.5 to 50 mg per day. Results: There was a mean increase in excess weight loss from 20.4% to 34.1% without the need for band readjustment. 2 patients had intolerance to topiramate and were changed to fluoxetine 40 mg per day. Conclusion: Topiramate may be a useful adjuvant for patients with AGB and binge eating disorder.

Complications of gastrectomy with lymphadenectomy in gastric cancer

BackgroundCurrently, gastrectomy and extended lymphadenectomy (LN) is the treatment of choice for gastric cancer. Although a survival rate benefit of D2 LN compared to D1 LN has been shown, the D2 LN procedure is not fully employed, due to possible higher morbidity and mortality rates. These higher rates are being questioned in more recent series, in which D1 and D2 LN complication rates have been similar. The aim of this study was to analyze the immediate postoperative complications of patients submitted to total or subtotal gastrectomy with D1 or D2 LN (according to the Japanese guidelines for gastric cancer) at the Gastrointestinal Surgery Division of the Medical School of São Paulo University, between January 2001 and April 2003.MethodsOne hundred consecutive patients were studied; 61 were men and 39, women. Total gastrectomy was performed in 52 patients (13 with D1 LN and 39 with D2 LN), and subtotal gastrectomy was performed in 48 (11 with D1 LN and 37 with D2 LN). Total or subtotal gastrectomy with D1 or D2 LN was performed according to the tumor extent and histological classification (Lauren’s diffuse or intestinal type), considering the patient’s general condition and the gastric cancer stage. Roux-en-Y reconstruction was performed in almost all patients.ResultsNo difference was observed regarding complications and mortality related to the extent of the gastrectomy. Although morbidity was higher in the D1 group, no significant difference was observed. Mortality was higher in the D1 group, and this was probably related to their poor surgical condition and more advanced tumors.ConclusionAccording to these results, it appears that total or subtotal gastrectomy with D2 LN in gastric cancer treatment, performed according to the Japanese guidelines, can be considered a safe procedure, with acceptable morbidity and mortality, when performed by a trained surgical team.

Endoscopic ultrasound versus endoscopic retrograde cholangiography for the diagnosis of choledocholithiasis: the influence of the size of the stone and diameter of the common bile duct

RACIONAL: A colangiografia retrograda endoscopica e metodo acurado porem invasivo para o diagnostico da coledocolitiase. A ecoendoscopia tambem e metodo bastante eficaz para a deteccao de calculo coledociano e apresenta riscos semelhantes aqueles de uma endoscopia digestiva convencional. OBJETIVOS: Comparar a acuracia da ecoendoscopia e da colangiografia endoscopica para o diagnostico do calculo da via biliar principal antes da colecistectomia laparoscopica e analisar a influencia do tamanho do calculo e do calibre da via biliar principal na eficacia diagnostica da ecoendoscopia. PACIENTES E METODOS: Duzentos e quinze pacientes com colecistolitiase sintomatica foram admitidos para colecistectomia laparoscopica. Destes, 68 (31,7%) apresentaram dilatacao da via biliar extra-hepatica a ecografia convencional e/ou alteracao de enzimas hepaticas e canaliculares. Foram, entao, submetidos a ecoendoscopia e colangiografia endoscopica, seguida de papilotomia, se qualquer um dos metodos sugerisse a presenca de coledocolitiase. Apos a papilotomia, o maior calculo foi recuperado e medido. A exploracao endoscopica ou cirurgica da via biliar foi considerada o padrao-ouro para o diagnostico de coledocolitiase. RESULTADOS: Todos os 68 pacientes foram submetidos a colecistectomia laparoscopica com colangiografia intra-operatoria, comprovando-se colecistolitiase neste grupo. A ecoendoscopia foi mais sensivel do que a colangiografia endoscopica para a deteccao de calculos coledocianos (97% vs. 67%). Para os calculos maiores de 4,0 mm, os metodos apresentaram sensibilidades semelhantes (96% vs. 90%). Os resultados da ecoendoscopia nao foram influenciados pelo tamanho do calculo ou pelo calibre do coledoco. CONCLUSOES: Para pacientes com risco intermediario para coledocolitiase, a ecoendoscopia e metodo mais sensivel do que a colangiografia endoscopica, especialmente para calculos pequenos.