[Helicobacter pylori infection and its association with alcohol consumption: a case-control study]. / Infección por Helicobacter pylori y su asociación con el consumo de alcohol. Estudio de casos y controles.

INTRODUCTION: There is a high prevalence worldwide of Helicobacter pylori (Hp) infection associated with gastritis and extending to gastric cancer. Reports have suggested that alcohol has antibacterial action and that its concentration and the amount consumed reduce the risk for Hp infection. In contrast, different studies suggest that tobacco and coffee consumption are risk factors for Hp infection, but their results are controversial. AIMS: To compare the frequency of alcohol consumption in patients infected by Hp with that of non-infected subjects and, as a secondary aim, to compare the association of smoking and coffee consumption with Hp infection. MATERIAL AND METHODS: A case-control study was conducted on Sinaloa State workers that underwent endoscopy and the Hp serology test. Cases were defined as patients with a positive Hp serology test or a positive biopsy with the rapid urease test. Alcohol consumption was categorized as: no consumption, low-risk, and at-risk. The sample included 269 subjects per group. Odds ratio (OR) and 95% confidence interval (CI) were calculated. RESULTS: In both groups, the mean age of the subjects was 45.7 (SD: 9) years (P=.99), 139 of the subjects were women (51.7%) and 130 were men (48.3%); alcohol consumption was present in 108 (40.1%) and 85 (31.6%) of the cases and controls, respectively (P=.039), OR 1.45 (95%CI 1.019-2.069). The quantity of grams of alcohol in subjects with at-risk consumption was significant; However, there were no significant differences in relation to smoking and coffee consumption between the groups. CONCLUSIONS: An association between alcohol consumption and HP infection was observed and no relation with HP infection was found with respect to smoking and coffee consumption.

Optimal network topologies for local search with congestion.

The problem of searchability in decentralized complex networks is of great importance in computer science, economy, and sociology. We present a formalism that is able to cope simultaneously with the problem of search and the congestion effects that arise when parallel searches are performed, and we obtain expressions for the average search cost both in the presence and the absence of congestion. This formalism is used to obtain optimal network structures for a system using a local search algorithm. It is found that only two classes of networks can be optimal: starlike configurations, when the number of parallel searches is small, and homogeneous-isotropic configurations, when it is large.

[Use of a temporal cardiac pacemaker in patients undergoing a major non-cardiac surgery]. / Empleo del marcapaso cardiaco temporal en pacientes sometidos a procedimiento de cirugia mayor no cardiaca.

This is a report of the use of transvenous temporal pacemaker in 18 patients, with an average age of 59.3 years, that under want non cardiac major surgery. They did not have cardiac simptoms but had conduction abnormalities in the preoperative electrocardiogram. A pacemaker was implanted as a prophylaxis against arrythmia during the transoperative and postoperative periods. There was no incidence of transoperative arrythmia. Three patients died in the immediate postoperative period, two due to duffuse carcinomatosis and one due to diabetic acidosis. The average duration of the implanted pacemaker was 12.7 days, and three patients required a permanent pacemaker. Case five is exemplificative of the benefits of the temporal pacemaker, he had a preoperative electrocardiogram showing trifascicular block, he was taken to the operating room and anesthesia was induced, the patient had a cardiac arrest but recovered without secuela; latter on a temporal pacemaker was inserted and the patient had surgery without cardiac problems.