Impact of chlorogenic acid on surface and phase properties of cholesterol-enriched phosphatidylcholine membranes.

This study analyses the insertion of Chlorogenic acid (CGA) in phosphatidylcholine (PC) membranes enriched with cholesterol (Chol). While cholesterol decreases the area per lipid and increases the dipole potential, CGA increases and decreases these values, respectively. When CGA is inserted into cholesterol-containing DMPC membranes, these effects cancel out, resulting in values that overlap with those of DMPC monolayers without Chol and CGA. The presence of CGA also compensates the increase of dipole potential produced by Chol which can be explain as a consequence of the orientation of CGA molecule at the interphase opposing the cholesterol dipole moieties and water dipoles. This compensatory effect is less effective when lipids lack carbonyl groups (CO). When monolayers are composed by unsaturated PCs the Chol compensation is found at higher concentrations of CGA due to the direct interaction between CGA and Chol. These results suggest that cholesterol modulates the interaction and distribution of CGA in the lipid membrane, which may have implications for its biological activity.

Notas acerca de la transfusión sanguínea en México / Notes about blood transfusion in Mexico

Resumen: La historia de la transfusión sanguínea es apasionante. En México, esta práctica se inició en el siglo XIX y a partir de entonces los avances y contribuciones de investigadores y clínicos fueron decisivos para su desarrollo e implementación en la práctica clínica. El objetivo de este trabajo es hacer una breve revisión histórica de la transfusión sanguínea en México.

Abstract: The history of blood transfusions is exciting. In Mexico this practice began in the XIX century and from this time the advances and contributions of researchers and clinicians were decisive for its development and implementation in the clinical practice. The aim of this paper is to make a brief review of the history of blood transfusion in Mexico.

Polimiositis y compromiso cardiaco / Cardiac involvement in polymyositis

Las miopatías idiopáticas son enfermedades que se caracterizan por cursar con una lesión muscula de tipo inflamatorio, sin embargo, también se ha encontrado que presentan compromiso del músculo cardiaco de forma importante, inclusive con desarrollo de falla cardiaca. Lo anterior constituye una causa frecuente de morbilidad y mortalidad en este grupo de pacientes. Al respecto, se presenta el caso de una paciente de 54 años con sospecha inicial de síndrome coronario agudo, quien cursó con polimiositis, dolor torácico y compromiso de la fracción de eyección.

Idiopathic myopathies are disorders characterized by inflammatory muscle damage. However, it has also been found that they may present significant muscle heart engagement, even with the development of heart failure. This is a frequent cause of morbidity and mortality in this group of patients. In this regard, the case of a 54 year old female patient with initial suspicion of acute coronary syndrome accompanied by polymyositis, chest pain and commitment of the ejection fraction, is presented.

Revision with plates of humeral nonunions secondary to failed intramedullary nailing.

PURPOSE: The objective of this study was to evaluate the results achieved after revision with plates of humeral nonunions secondary to failed intramedullary nailing. METHODS: We retrospectively evaluated 32 patients with humeral nonunions secondary to failed intramedullary nailing, treated by internal fixation with plates between 1998 and 2012. Nonunions were diaphyseal in 19 cases, they were located in the proximal humeral metaphysis in nine cases, and in the distal humeral metaphysis in four cases. There were 11 atrophic nonunions and 21 oligotrophic nonunions. Initial treatment was performed with static locked nails in 12 cases, nails with expansive locking systems in 11 cases, and using thin elastic nails in nine cases. The nails were placed antegrade in 18 cases and retrograde in 14 cases. Time between initial surgery and revision surgery averaged 14.5 months. In seven diaphyseal nonunions, the intramedullary nail was left in-situ. Bone graft was added in 25 cases. RESULTS: Follow-up averaged 35 months. Union was achieved in all cases, after an average of 3.8 months. Disabilities of the Arm, Shoulder and Hand (DASH) score at last follow-up averaged 14 points, and Constant's score averaged 82 points. The analogue scale of pain averaged 0.8 points. Out of seven patients with radial nerve compromise, six recovered completely and one needed tendon transfers. CONCLUSIONS: Revision with plates after failed intramedullary humeral nailing achieved union and good predictable objective and subjective results in all cases. Adequate implant selection and meticulous surgical technique are necessary to achieve successful osteosynthesis and bony union.

Extremophile culture collection from Andean lakes: extreme pristine environments that host a wide diversity of microorganisms with tolerance to UV radiation.

A total of 88 bacterial strains were isolated from six Andean lakes situated at altitudes ranging from 3,400 to 4,600 m above sea level: L. Aparejos (4,200 m), L. Negra (4,400 m), L. Verde (4,460 m), L. Azul (4,400 m), L. Vilama (4,600 m), and Salina Grande (3,400 m). Salinity ranged from 0.4 to 117 ppm. General diversity was determined by denaturing gradient gel electrophoresis (DGGE) analysis. From the excised DGGE bands, 182 bacterial sequences of good quality were obtained. Gammaproteobacteria and Cytophaga/Flavobacterium/Bacteroides (CFB) were the most abundant phylogenetic groups with 42% and 18% of identified bands, respectively. The isolated strains were identified by sequence analysis. Isolated bacteria were subjected to five different UV-B exposure times: 0.5, 3, 6, 12, and 24 h. Afterwards, growth of each isolate was monitored and resistance was classified according to the growth pattern. A wide interspecific variation among the 88 isolates was observed. Medium and highly resistant strains accounted for 43.2% and 28.4% of the isolates, respectively, and only 28.4% was sensitive. Resistance to solar radiation was equally distributed among the isolates from the different lakes regardless of the salinity of the lakes and pigmentation of isolates. Of the highly resistant isolates, 44.5% belonged to gammaproteobacteria, 33.3% to betaproteobacteria, 40% to alphaproteobacteria, 50% to CFB, and among gram-positive organisms, 33.3% were HGC and 44.5% were Firmicutes. Most resistant strains belonged to genera like Exiguobaceterium sp., Acinetobacter sp., Bacillus sp., Micrococcus sp., Pseudomonas sp., Sphyngomonas sp., Staphylococcus sp., and Stenotrophomonas sp. The current study provides further evidence that gammaproteobacteria are the most abundant and the most UV-B-resistant phylogenetic group in Andean lakes and that UV resistance in bacteria isolated from these environments do not depend on pigmentation and tolerance to salinity.