Almost routine prophylactic cholecystectomy during laparoscopic gastric bypass is safe

Background Morbidly obese patients are at high risk to develop gallstones, and rapid weight loss after bariatric surgery further enhances this risk. The concept of prophylactic cholecystectomy during gastric bypass has been challenged recently because the risk may be lower than reported earlier and because cholecystectomy during laparoscopic gastric bypass may be more difficult and risky. <p>Methods A review of prospectively collected data on 772 patients who underwent laparoscopic primary gastric bypass between January 2000 and August 2007 was performed. The charts of patients operated before 2004 were retrospectively reviewed regarding preoperative echography and histopathological findings.</p> <p>Results Fifty-eight (7.5%) patients had had previous cholecystectomy. In the remaining patients, echography showed gallstones or sludge in 81 (11.3%). Cholecystectomy was performed at the time of gastric bypass in 665 patients (91.7%). Gallstones were found intraoperatively in 25 patients (3.9%), for a total prevalence of gallstones of 21.2%. The age of patients with gallstones was higher than that of gallstone-free patients (43.5 vs 38.7 years, p < 0.0001). Of the removed specimens, 81.8% showed abnormal histologic findings, mainly chronic cholecystitis and cholesterolosis. Cholecystectomy was associated with no procedure-related complication, prolonged duration of surgery by a mean of 19 min (4-45), and had no effect on the duration of hospital stay. Cholecystectomy was deemed too risky in 59 patients (8.3%) who were prescribed a 6-month course of ursodeoxycolic acid.</p> <p>Conclusion Concomitant cholecystectomy can be performed safely in most patients during laparoscopic gastric bypass and does not prolong hospital stay. As such, it is an acceptable form of prophylaxis against stones forming during rapid weight loss. Whether it is superior to chemical prophylaxis remains to be demonstrated in a large prospective randomized study.</p>

Immunoblotting for the serodiagnosis of Helicobacter pylori infection in Brazilian patients with and without gastric carcinoma

We evaluated the performance of a commercial immunoblotting in the serodiagnosis of Helicobacter pylori infection in Brazilian patients. The presence of anti-H. pylori antibodies was also investigated in a group of 20 duodenal ulcer patients after successful treatment. One hundred and ninety one patients were studied. Among the 164 infected patients, 46 had gastric carcinoma. The duodenal ulcer patients were treated with antimicrobial drugs and the eradication of the microorganism was confirmed in all of them one month after the end of the treatment by the 13C-urea breath test. Sera were assayed for H. pylori antibodies using the Helicoblot 2.0 (Genelabs Diagnostics, Singapore). The sensitivity, specificity, positive, and negative predictive values of the test were 93.9%, 92.6%, 98.7%, and 71.4%, respectively. The sensitivity of the test was similar in patients with (93.5%) and without (95.7%) gastric carcinoma. Twenty-four months after the end of the treatment, the band of 116 kDa was still detected in one of the patients. In conclusion, the Helicoblot 2.0 is an accurate test to diagnose H. pylori infection and although it can not be employed to monitor the bacterium eradication, it may be useful for diagnosing past infection, especially in gastric carcinoma patients.

Differences in the stability of the plasmids of Yersinia pestis cultures in vitro: impact on virulence

Plasmid and chromosomal genes encode determinants of virulence for Yersinia pestis, the causative agent of plague. However, in vitro, Y. pestis genome is very plastic and several changes have been described. To evaluate the alterations in the plasmid content of the cultures in vitro and the impact of the alterations to their pathogenicity, three Y. pestis isolates were submitted to serial subculture, analysis of the plasmid content, and testing for the presence of characteristic genes in each plasmid of colonies selected after subculture. Different results were obtained with each strain. The plasmid content of one of them was shown to be stable; no apparent alteration was produced through 32 subcultures. In the other two strains, several alterations were observed. LD50 in mice of the parental strains and the derived cultures with different plasmid content were compared. No changes in the virulence plasmid content could be specifically correlated with changes in the LD50.

Is lean body mass decreased after obesity treatment by adjustable gastric banding?

BACKGROUND: There is concern that surgically-induced weight loss in obese subjects is associated with a disproportionate decrease in lean body mass (LBM) and in skeletal muscle mass (SMM), a major constituent of LBM. To address this issue, 1) we measured total and regional body composition following gastric banding in a group of obese subjects, and 2) we compared these data to those of a non-surgical control group of similar age and body size. METHODS: Body composition was assessed by dual-energy X-ray absorptiometry (DEXA) before and after laparoscopic adjustable silicone gastric banding (LAGB) in 32 women (after 1 year: age 43.7+/-8.4 years, BMI 36.4+/-5.9 kg/m2, mean+/-SD), and in 117 control women (age 44.5+/-7.5 years; BMI 36.7+/-5.5 kg/m2) referred for non-surgical weight management, prior to weight loss. SMM was estimated using a published equation based on LBM of the extremities (appendicular LBM). RESULTS: 1 year after LAGB, body weight loss (-23.7+/-11.6 kg, P<10(-6)) was mainly due to decreased fat mass (-21.2+/-11.2 kg, P<10(-6)), and total LBM was modestly, although significantly, decreased (-2.1+/-4.2 kg, P=0.01). Appendicular LBM (-0.7+/-2.7 kg) and total SMM (-0.9+/-3.0 kg) were not significantly modified. None of the body composition variables was significantly decreased in weight-reduced subjects compared to the control group, especially appendicular LBM and total SMM. CONCLUSIONS: Results provide no evidence for a decrease in appendicular LBM and total SMM with weight loss following LAGB. Follow-up of these obese patients revealed a very favorable pattern of change in total and regional body composition, with preservation of muscle mass.

Gestion des hypoglycémies après le bypass gastrique [Management of hyperinsulinemic hypoglycemia post-gastric bypass surgery].

Gastric bypass surgery is an effective treatment for morbid obesity, allowing a substantial weight loss together with an improvement of the cardiovascular and metabolic comorbidities, particularly the glucose control. However, after gastric bypassing, an imbalance between sensitivity and insulin secretion may be observed. This disorder gives rise to hyperinsulinemic hypoglycemia (late dumping syndrome) and is characterized by a dizziness that can be disabling. This problem must be distinguished from conditions provoking similar symptoms, as for instance the early dumping syndrome and the food restriction-related hypoglycemia. Since all these conditions need a particular management, their distinction is essential.

Gastric bypass in morbid obese patients is associated with reduction in adipose tissue inflammation via N-oleoylethanolamide (OEA)-mediated pathways.

Paradoxically, morbid obesity was suggested to protect from cardiovascular co-morbidities as compared to overweight/obese patients. We hypothesise that this paradox could be inferred to modulation of the "endocannabinoid" system on systemic and subcutaneous adipose tissue (SAT) inflammation. We designed a translational project including clinical and in vitro studies at Geneva University Hospital. Morbid obese subjects (n=11) were submitted to gastric bypass surgery (GBS) and followed up for one year (post-GBS). Insulin resistance and circulating and SAT levels of endocannabinoids, adipocytokines and CC chemokines were assessed pre- and post-GBS and compared to a control group of normal and overweight subjects (CTL) (n=20). In vitro cultures with 3T3-L1 adipocytes were used to validate findings from clinical results. Morbid obese subjects had baseline lower insulin sensitivity and higher hs-CRP, leptin, CCL5 and anandamide (AEA) levels as compared to CTL. GBS induced a massive weight and fat mass loss, improved insulin sensitivity and lipid profile, decreased C-reactive protein, leptin, and CCL2 levels. In SAT, increased expression of resistin, CCL2, CCL5 and tumour necrosis factor and reduced MGLL were shown in morbid obese patients pre-GBS when compared to CTL. GBS increased all endocannabinoids and reduced adipocytokines and CC chemokines. In morbid obese SAT, inverse correlations independent of body mass index were shown between palmitoylethanolamide (PEA) and N-oleoylethanolamide (OEA) levels and inflammatory molecules. In vitro, OEA inhibited CCL2 secretion from adipocytes via ERK1/2 activation. In conclusion, GBS was associated with relevant clinical, metabolic and inflammatory improvements, increasing endocannabinoid levels in SAT. OEA directly reduced CCL2 secretion via ERK1/2 activation in adipocytes.

Improving binding affinity and stability of peptide ligands by substituting glycines with D-amino acids.

Improving the binding affinity and/or stability of peptide ligands often requires testing of large numbers of variants to identify beneficial mutations. Herein we propose a type of mutation that promises a high success rate. In a bicyclic peptide inhibitor of the cancer-related protease urokinase-type plasminogen activator (uPA), we observed a glycine residue that has a positive ϕ dihedral angle when bound to the target. We hypothesized that replacing it with a D-amino acid, which favors positive ϕ angles, could enhance the binding affinity and/or proteolytic resistance. Mutation of this specific glycine to D-serine in the bicyclic peptide indeed improved inhibitory activity (1.75-fold) and stability (fourfold). X-ray-structure analysis of the inhibitors in complex with uPA showed that the peptide backbone conformation was conserved. Analysis of known cyclic peptide ligands showed that glycine is one of the most frequent amino acids, and that glycines with positive ϕ angles are found in many protein-bound peptides. These results suggest that the glycine-to-D-amino acid mutagenesis strategy could be broadly applied.

Gastric banding induces negative bone remodelling in the absence of secondary hyperparathyroidism: potential role of serum C telopeptides for follow-up.

OBJECTIVE: Data about the consequences of laparoscopic adjustable gastric banding (LAGB) on phospho-calcic and bone metabolism remain scarce. SUBJECTS: We studied a group of 37 obese premenopausal women (age: 24-52 y; mean BMI = 43.7 kg/m2) who underwent LAGB. METHODS: Serum calcium, phosphate, alkaline phosphatase, parathormone (PTH), vitamin D3, serum C-telopeptides, IGFBP-3 and IGF-1 were measured at baseline, 6, 12, 18 and 24 months after surgery. Body composition, bone mineral content (BMC) and density (BMD) were measured using dual-X-ray absorptiometry (DXA) at baseline, 6, 12 and 24 months after surgery. RESULTS: There was no clinically significant decrease of calcemia; PTH remained stable. Serum telopeptides increased by 100% (P < 0.001) and serum IGFBP-3 decreased by 16% (P < 0.001) during the first 6 months, and then stabilized, whereas IGF-1 remained stable over the 2 y. BMC and BMD decreased, especially at the femoral neck; this decrease was significantly correlated with the decrease of waist and hip circumference. CONCLUSIONS: We concluded that there was no evidence of secondary hyperparathyroidism 24 months after LAGB. The observed bone resorption could be linked to the decrease of IGFBP-3, although this decrease could be attributable to other confounding factors. Serum telopeptides seem to be a reliable marker of bone metabolism after gastric banding. DXA must be interpreted cautiously during major weight loss, because of the artefacts caused by the important variation of fat tissue after LAGB.

Estimation of time of death in relation to gastric contents

Introduction: Estimation of the time since death based on the gastric content is still a controversy subject. Many studies have been achieved leaving the same incertitude: the intra- and inter-individual variability. Aim: After a homicidal case where a specialized gastroenterologist was cited to estimate the time of death based on the gastric contents and his experience in clinical practice. Consequently we decided to make a review of the scientific literature to see if that method was more reliable nowadays. Material and methods: We chose articles from 1979 that describe the estimation of the gastric emptying rate according to several factors and the forensic articles about the estimation of the time of death in relation with the gastric content. Results: Most of the articles cited by the specialized gastroenterologist were studies about living healthy people and the effects of several factors (medication, supine versus upside-down position, body mass index or different type of food). Forensic articles frequently concluded that the estimation of the time since death by analyzing the gastric content can be used but not as the unique method. Conclusion: Estimation of the time since death by analyze of the gastric contents is a method that can be used nowadays. But it cannot be the only method as the inter- and intra-individual variability remains an important bias.

Use of unmodified starches and partial removal of serum to improve Granada medium stability

The use of 1% unmodified rice starch and 1% horse serum instead of 2% soluble starch and 5% serum in Granada medium is described. These components result in a medium of increased stability, preventing spoilage after a few days of storage at room temperature

Compositional hypotheses of subcompositional stability and specific perturbation change and their testing

In standard multivariate statistical analysis common hypotheses of interest concern changes in mean vectors and subvectors. In compositional data analysis it is now well established that compositional change is most readily described in terms of the simplicial operation of perturbation and that subcompositions replace the marginal concept of subvectors. To motivate the statistical developments of this paper we present two challenging compositional problems from food production processes.Against this background the relevance of perturbations and subcompositions can beclearly seen. Moreover we can identify a number of hypotheses of interest involvingthe specification of particular perturbations or differences between perturbations and also hypotheses of subcompositional stability. We identify the two problems as being the counterpart of the analysis of paired comparison or split plot experiments and of separate sample comparative experiments in the jargon of standard multivariate analysis. We then develop appropriate estimation and testing procedures for a complete lattice of relevant compositional hypotheses

Assessing protein stability of the dimeric DNA-binding domain of E2 human papillomavirus 18 with molecular dynamics

The objective of this study is to understand the structural flexibility and curvature of the E2 protein of human papillomavirus type 18 using molecular dynamics (6 ns). E2 is required for viral DNA replication and its disruption could be an anti-viral strategy. E2 is a dimer, with each monomer folding into a stable open-faced β-sandwich. We calculated the mobility of the E2 dimer and found that it was asymmetric. These different mobilities of E2 monomers suggest that drugs or vaccines could be targeted to the interface between the two monomers.

Characterization of 23S rRNA domain V mutations in gastric biopsy patients from the eastern Amazon

Resistance of Helicobacter pylori to clarithromycin is characterised by simple point mutations in the 23S ribosomal RNA (rRNA) gene and is responsible for the majority of cases of failure to eradicate this bacterium. In this paper, we characterised the variability of the 23S rRNA gene in biopsies of patients with gastric pathologies in the eastern Amazon (Northern Region of Brazil) using PCR and sequencing. A total of 49 sequences of H. pylori strains were analysed and of those, 75.6% presented nucleotide substitutions: A2142G (3.3%), T2182C (12.9%), G2224A (6.45%), T2215C (61.3%), A2192G (3.3%), G2204C (6.4%) and T2221C (6.4%). Of the mutations identified, four are known mutations related to cases of resistance and 16.1% are not yet described, revealing a high prevalence of mutations in the H. pylori 23S rRNA gene among the strains circulating in the in the eastern Amazon. The high prevalence in individuals with gastric pathologies in the Northern Region of Brazil demonstrates the need for characterising the profile of these strains to provide correct therapy for patients, considering that mutations in this gene are normally associated with resistance to the primary medication used in controlling H. pylori infection.