[Electrical alternans, electrocardiogram pattern in the diagnosis of a severe heart disease]. / Alternancia eléctrica, patrón electrocardiográfico en el diagnóstico de enfermedad cardiaca grave.

Electrical alternans is a broad term that describes alternate-beat variation in the direction, amplitude and duration of any component of the ECG wave-form. It is associated with cardiac tamponade, serious ventricular arrhythmias, and sudden death. We present the clinical case of a 77-year-old female with electrical alternans, from which a diagnosis of cardiac tamponade was established.

Alternancia eléctrica, patrón electrocardiográfico en el diagnóstico de enfermedad cardiaca grave / Electrical alternans, electrocardiogram pattern in the diagnosis of a severe heart disease

La alternancia eléctrica es un amplio concepto que describe las variaciones, latido a latido, en la dirección, amplitud y/o duración de cualquier componente del electrocardiograma. Se asocia a taponamiento cardiaco, arritmias malignas y muerte súbita. Presentamos el caso de una paciente de 77 años con alternancia eléctrica a partir de la cual se llegó al diagnóstico de taponamiento cardiaco (AU)

Electrical alternans is a broad term that describes alternate-beat variation in the direction, amplitude and duration of any component of the ECG wave-form. It is associated with cardiac tamponade, serious ventricular arrhythmias, and sudden death. We present the clinical case of a 77-year-old female with electrical alternans, from which a diagnosis of cardiac tamponade was established (AU)

Crystallization and identification of the glycosylated moieties of two isoforms of the main allergen Hev b 2 and preliminary X-ray analysis of two polymorphs of isoform II.

Latex from Hevea brasiliensis contains several allergenic proteins that are involved in type I allergy. One of them is Hev b 2, which is a beta-1,3-glucanase enzyme that exists in different isoforms with variable glycosylation content. Two glucanase isoforms were isolated from trees of the GV-42 clone by gel filtration, affinity and ion-exchange chromatography. Isoform I had a carbohydrate content of about 20%, with N-linked N-acetyl-glucosamine, N-acetyl-galactosamine, fucose and galactose residues as the main sugars, while isoform II showed 6% carbohydrate content consisting of N-acetyl-glucosamine, fucose, mannose and xylose. Both isoforms were crystallized by the hanging-drop vapour-diffusion method. Isoform I crystals were grown using 0.2 M trisodium citrate dihydrate, 0.1 M Na HEPES pH 7.5 and 20%(v/v) 2-propanol, but these crystals were not appropriate for data collection. Isoform II crystals were obtained under two conditions and X-ray diffraction data were collected from both. In the first condition (0.2 M trisodium citrate, 0.1 M sodium cacodylate pH 6.5, 30% 2-propanol), crystals belonging to the tetragonal space group P4(1) with unit-cell parameters a = b = 150.17, c = 77.41 A were obtained. In the second condition [0.2 M ammonium acetate, 0.1 M trisodium citrate dihydrate pH 5.6, 30%(w/v) polyethylene glycol 4000] the isoform II crystals belonged to the monoclinic space group P2(1), with unit-cell parameters a = 85.08, b = 89.67, c = 101.80 A, beta = 113.6 degrees. Preliminary analysis suggests that there are four molecules of isoform II in both asymmetric units.

Hadrurin, a new antimicrobial peptide from the venom of the scorpion Hadrurus aztecus.

A new antimicrobial peptide, hadrurin, was isolated from the venom of the Mexican scorpion Hadrurus aztecus, by gel filtration on a Sephadex G-50 column, followed by high performance liquid chromatography. It is a basic peptide composed of 41 amino-acid residues with a molecular mass of 4436 Da, and contains no cysteines. A model of the three-dimensional folding of hadrurin is compatible with that of an amphipatic molecule with two alpha-helical segments. Hadrurin demonstrates antimicrobial activity at low micromolar concentration, inhibiting the growth of bacteria such as: Salmonella thyphi, Klebsiella pneumoniae, Enterococcus cloacae, Pseudomonas aeruginosa, Escherichia coli and Serratia marscences. It also shows cytolytic activity when tested in human erythrocytes. Hadrurin and two analogs (C-terminal amidated, and all D-enantiomer) were chemically synthesized. They were used to study the possible molecular mechanism of action by testing their ability to dissipate the diffusion potential of liposomes of different compositions. The results obtained indicate that there are no specific receptor molecules for the action of hadrurin, and the most probable mechanism is through a membrane destabilization activity. It is surmised that hadrurin is used by the scorpion as both an attack and defense element against its prey and putative invasive microorganisms. It is a unique peptide among all known antimicrobial peptides described, only partially similar to the N-terminal segment of gaegurin 4 and brevinin 2e, isolated from frog skin. It would certainly be a model molecule for studying new antibiotic activities and peptide-lipid interactions.

Passive forces in mammalian skeletal muscle: a freely-jointed and worm-like chain.

The passive mechanical properties of whole muscle in active and nonactive states are compared. The experimental results are presented as stress-strain curves, which are analyzed in the framework of the current theoretical background [viz. the freely-jointed chain model (FJCM) and the worm-like chain model (WLCM)] in a semi-quantitative fashion. This analysis shows that both models can explain the mechanical behavior of whole muscle in non-active state. In the active state, the presence of crossbridges alters the mechanical response, leading to a markedly different behavior, as expected. A discussion of the mechanisms involved and the interpretation of the parameters required for the fitting of the stress-strain curves is also presented.

[Can we detect mental disorders in primary care? Usefulness and agreement of 2 diagnostic instruments]. / Podemos detectar trastornos mentales en atención primaria? Utilidad y concordancia de dos instrumentos diagnósticos.

OBJECTIVES: The main objective was to evaluate the use of two diagnostic instruments for mental disorders in primary care (PC): the PRIME-MD and the Goldberg anxiety and depression scales. Second, to determine the concordance between the two tests and evaluate the quality of psychiatric diagnosis records in the clinical notes. DESIGN: Crossover observational study. SETTING: Luis Vives Health Centre (EAP 1), Alcalá de Henares (Madrid). PATIENTS: 175 patients who attended for consultation on-demand over three months. MEASUREMENTS AND MAIN RESULTS: Each patient was given the PRIME-MD test for detecting disorders of depression, anxiety, food, alcohol and body form; and the Goldberg scale to evaluate anxiety and depression. The clinical records were then reviewed for previous psychiatric diagnoses. The two scales were compared and the level of concordance obtained. The PRIME-MD found that 78 patients (44.6%) had some mental disorder, the most frequent being depression (32.6% of the total). The Goldberg scale detected 89 patients (50.8%) with some suspected mental disorder: here too, the most common was depression (41.7% of the total). The best indication of concordance between the two tests was the diagnosis of anxiety disorders: kappa = 0.68 (CI 95%, 0.53-0.82). CONCLUSIONS: Both scales seem useful instruments for detecting a pathology which is very common in PC clinics: mental disorders. Moreover, the concordance between the two scales is acceptable. There was poor recording of psychiatric diagnoses in clinical records.

[Septicemia associated with central venous catheterization in a children's hospital. A multivariate study]. / Septicemias asociadas a la cateterización venosa central en un hospital infantil. Estudio multivariante.

BACKGROUND: The blood stream infections (BSI) are the principal nosocomial infection in the child hospitals. In this study we estimate the incidence of BSI associated with central venous catheterization, and estimate different risk and protective factors, through a multivariate study. MATERIAL AND METHODS: The study have followed in a prospective way during 6 months all the children with central venous catheterization (489 catheters), from the moment of insertion until withdrawal, collecting various data previous to the development of the infection: place of insert, type of catheter, duration, clinic information, microbiology, and the treatments administered through the catheter. In was accomplished an multivariate analysis with logistic regression, for two principal effect variables, the catheter colonization and the catheter related BSI. RESULTS: The incidence of catheter related BSI was 5.5% and for local infection 11.2%. The density of incidence was 3.15 and 6.42 for each 1,000 catheters-day, respectively. The logistic regression model included: colonization of the skin in the insertion point > 15 colonies, days with antibiotics through catheter, use of lipidic parenteral solutions and fever, previous to the infection. The area under the ROC curve was 0.72. CONCLUSIONS: In children with septicemias associated with central catheterization the predictors or sentry criterion for the decision on when to withdraw a catheter are colonization (> 15 colonies) of the insert point, together with the use of lipidic parenteral solutions or extended antibiotic treatment.