Fernando Chaves

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The effect of several drugs on the edema-forming activity of Bothrops asper venom was studied plethysmographically using the mouse foot pad assay. Bothrops asper venom induced a dose-dependent edema which developed rapidly and peaked 1 hr after envenomation. Incubation of venom with EDTA before injection resulted in a significant reduction of edema. In(More)
OBJECTIVES To evaluate the current prevalence of the three clonal groups O25b:H4-B2-ST131, O15:H1-D-ST393 and CGA-D-ST69 (where ST stands for sequence type) among Escherichia coli isolates causing extraintestinal infections in Spain and to characterize their virulence background, 500 consecutive non-duplicate E. coli isolates causing extraintestinal(More)
Local tissue damage induced by crotaline snake venoms includes edema, myonecrosis, hemorrhage, and an inflammatory response associated with a prominent cellular infiltrate. The role of neutrophils in the local tissue damage induced by Bothrops asper snake venom and by myotoxin I, a phospholipase A2 isolated from this venom, was investigated. Male Swiss mice(More)
Diffuse neuronal migration disorders associated with epilepsy can now be recognized by modern neuroimaging techniques, particularly high-resolution MRI. We report 10 patients with a recently described MRI picture of continuous or generalized band heterotopia underlying the cortical mantle, giving the appearance of a "double cortex." They have epilepsy, and(More)
The molecular basis for isoniazid resistance in Mycobacterium tuberculosis is complex. Putative isoniazid resistance mutations have been identified in katG, ahpC, inhA, kasA, and ndh. However, small sample sizes and related potential biases in sample selection have precluded the development of statistically valid and significant population genetic analyses(More)
OBJECTIVE To characterise the clinical features, associations and outcome in a contemporary series of patients with Streptococcus bovis bacteraemia (SBB). METHODS Retrospective analysis of all episodes of SBB at the University Hospital 12 de Octubre (Madrid, Spain) between January 1997 and November 2008 was performed. Patient data were reviewed, focusing(More)
A clinical strain of Acinetobacter calcoaceticus resistant to carbapenems was isolated from a blood culture sample from an inpatient in a hospital in Madrid (Spain) during a large outbreak of infection (affecting more than 300 inpatients), caused by a multidrug-resistant Acinetobacter baumannii clone. The carbapenem resistance in both the A. calcoaceticus(More)
Fifty-three children who attended the emergency department with community-associated (CA) Staphylococcus aureus skin and soft tissue infections (SSTIs) were enrolled in the study. Seven cases of infection (13.2%) were due to methicillin-resistant S. aureus (MRSA). Twelve of 46 available isolates (26.1%) were Panton-Valentine leukocidin (PVL)-positive.(More)
The time-course and composition of inflammatory infiltrate in mouse gastrocnemius injected with Bothrops asper venom was studied. The venom induced myonecrosis, and a prominent decrease in muscle levels of creatine kinase (CK) as early as 3 hr after envenomation. Inflammatory infiltrate was scarce by 6 hr. but increased markedly at 24, 48 and 72 hr. Samples(More)
The resistance of Acinetobacter baumannii strains to carbapenems is a worrying problem in hospital settings. The main mechanism of carbapenem resistance is the expression of β-lactamases (metalloenzymes or class D enzymes). The mechanisms of the dissemination of these genes among A. baumannii strains are not fully understood. In this study we used two(More)