SummaryWe conducted a small mammal trapping study to investigate temporal variation in prevalence of infection in hantavirus reservoir populations in the Patagonian Andes mountain range, Rio Negro province, Argentina. Rodent blood samples collected in natural and periurban habitats and at the home of an hantavirus pulmonary syndrome (HPS) case patient were analysed by enzyme-linked immunosorbent assay. Organ tissue samples were tested by polymerase chain reaction (PCR) and nucleotide sequence analysis. Eight species of 1032 rodents were captured in 15 551 trap nights, giving an overall trap success of 6.6%. Hantavirus antibody was detected in 30 of 555 Oligoryzomys longicaudatus (reservoir of Andes virus), three of 411 Abrothrix longipilis, and one of 10 Loxodontomys micropus. Antibody prevalences in O. longicaudatus were 13.7% in spring 1996, 59.3% in summer 1996, 2.1% in autumn 1997, 12.4% in winter 1997 and 3.1% in spring 1997. A much higher antibody prevalence (33%) was found during trapping around the residence of an HPS case patient. Higher prevalences were found in older male O. longicaudatus. There was no apparent correlation of antibody prevalence with rodent population density, or of rodent population density or antibody prevalence with numbers of human cases. For an HPS case that occurred in our study area in 1997, we identi®ed the probable rodent reservoir and likely site of exposure by matching the genetic sequences of virus obtained from a rodent and the HPS case patient.

Background and Purpose-The metabolic syndrome (MetS) might confer a higher resistance to intravenous thrombolysis in acute middle cerebral artery (MCA) ischemic stroke. MetS increases the risk of stroke in women to a greater extent than in men. We aimed to investigate whether there might be sex differences in the impact of MetS on the response to intravenous thrombolysis for acute MCA ischemic stroke. Methods-We prospectively studied consecutive ischemic stroke patients, treated with intravenous tissue-type plasminogen activator according to SITS-MOST criteria, with an MCA occlusion on prebolus transcranial Doppler examination.Resistance to thrombolysis was defined as the absence of complete MCA recanalization 24 hours after tissue-type plasminogen activator infusion by transcranial Doppler criteria. MetS was diagnosed according to the criteria established by the American Heart Association/National Heart, Lung, and Blood Institute 2005 statement. Results-A total of 125 patients (75 men, 50 women; mean age, 67.6Ϯ11 years) were included. MetS was diagnosed in 76 (61%) patients. Resistance to clot lysis at 24 hours was observed in 53 (42%) patients. Two multivariate-adjusted, logistic-regression models identified that MetS was associated with a higher resistance to tissue-type plasminogen activator, independently of other significant baseline variables (odds ratioϭ9.8; 95% CI, 3.5 to 27.8; Pϭ0.0001) and of the individual components of the MetS. The MetS was associated with a significantly higher odds of resistance to thrombolysis in women (odds ratioϭ17.5; 95% CI, 1.9 to 163.1) than in men (odds ratioϭ5.1; 95% CI, 1.6 to 15.6; P for interactionϭ0.0004). Conclusions-The effect of MetS on the resistance to intravenous thrombolysis for acute MCA ischemic stroke appears to be more pronounced in women than in men. (Stroke. 2009;40:344-349.)

Tissue fixation, a central element in histotechnology, is currently performed with chemical compounds potentially harmful for human health and the environment. Therefore, alternative fixatives are being developed, including alcohol-based solutions. We evaluated several ethanol-based mixtures with additives to study fixative penetration rate, tissue volume changes, and morphologic effects in the bovine testis. Fixatives used were Bouin solution, 4% formaldehyde (F4), 70% ethanol (E70), E70 with 1.5% glycerol (E70G), E70 with 5% acetic acid (E70A), E70 with 1.5% glycerol and 5% acetic acid (E70AG), and E70 with 1.5% glycerol, 5% acetic acid, and 1% dimethyl sulfoxide (DMSO; E70AGD). Five-millimeter bovine testicular tissue cubes could be completely penetrated by ethanol-based fixatives and Bouin solution in 2-3 h, whereas F4 required 21 h. Bouin solution produced general tissue shrinkage, whereas the other fixatives (alcohol-based and F4) caused tissue volume expansion. Although Bouin solution is an excellent fixative for testicular tissue, ethanol-based fixatives showed good penetration rates, low tissue shrinkage, and preserved sufficient morphology to allow identification of the stages of the seminiferous epithelium cycle, therefore representing a valid alternative for histotechnology laboratories. Common additives such as acetic acid, glycerol, and DMSO offered marginal benefits for the process of fixation; E70AG showed the best preservation of morphology with excellent nuclear detail, close to that of Bouin solution.