Molecular epidemiology of methicillin-resistant Staphylococcus aureus from different population groups in Argentina.

OBJECTIVES: In Latin America, methicillin-resistantStaphylococcus aureus (MRSA) is a leading cause of nosocomial infections. Limited studies have addressed the molecular epidemiology of MRSA clones in Argentina, characterised by continuous human migratory movements. The aim of this study was to describe the MRSA epidemiology, including distinct patient populations from different regions of the country. METHODS: MRSA strains were collected in epidemiological studies conducted from 2009 to 2015 in three cities (Formosa, Córdoba and Tucumán) and involving four population groups: community adult patients; hospitalised adults; hospitalised children; and healthy children (nasal colonisation). Antimicrobial susceptibility testing, SCCmec and Panton-Valentine leukocidin (PVL) typing, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were performed. RESULTS: A total of 120 MRSA isolates were recovered with an important population diversity in the groups studied; in community adult patients, MRSA isolates corresponded to ST5, ST267 and ST1619; from hospitalised adults they were ST97, ST5, ST72, ST125, ST200, ST647, ST747, ST935 and ST2941; from hospitalised children they were ST5, ST30, ST34, ST1163 and ST1619; and from colonised children they were ST5, ST125, ST34, ST100, ST1619, ST207 and ST1163. Results of SCCmec typing showed SCCmec I, SCCmec IIIA, SCCmec IV and SCCmec ND associated or not with PVL genes. CONCLUSIONS: MRSA genetic lineages have differing distribution in the three regions. The most prevalent was ST5 in colonisation, community and invasive settings. Here we describe ST34-SCCmec IV clone for the first time in the hospitalised paediatric population. These findings contribute to the understanding of epidemiological changes in recent years.

Relationship Between Body Mass and Forewing Length in Neotropical Ichneumonidae (Insecta: Hymenoptera).

Biomass is an important indicator of various ecological factors in insect populations and communities. Although the utility of this variable is proven, it is usually dismissed in ecological studies, generally, because of the difficulty of measuring it. Considering that insect biomass is apparently declining worldwide, here, we aimed to test the accuracy of forewing length as an estimator of body mass in Neotropical Ichneumonidae to help in monitoring insect biomass. Forewing length and dry body mass were measured in 728 individuals from distinct localities in Venezuela and Ecuador. A clear log-linear relationship existed between the two variables, and a log-linear regression had significant and strong predictive power of mass based on wing length. To derive the final values of mass from predictions made using our equation, we used an exponential transformation. We present an R function for predicting mass from wing length. We consider our findings applicable to many Neotropical species of Ichneumonidae, and helpful especially when specimens are measured in dry collections.

Epidemiologic Study and Genotyping of BK Virus in Renal Transplant Recipients.

BK virus (BKV) infection occurs during childhood and remains latent in the urinary tract. The virus is reactivated in immunosuppressed patients, particularly in those with cellular immunity deficiency, allowing its detection in urine and blood. Nephropathy caused by the virus in renal transplantation recipients may lead to graft failure. The purpose of this study is to know the prevalence of BKV variables in renal transplantation recipients and to evaluate their clinical evolution through molecular methods of "in house" development. Urine and peripheral blood samples from 66 renal transplantation recipients from the province of Buenos Aires, Argentina, were systematically analyzed every 3 months as well as when there was graft dysfunction. Renal biopsies, which were included in the BKV detection study, were performed on those patients with graft dysfunction. Genotyping of 24 BKVs was performed, and the following distribution was found: 21 (87.5%) belonged to subtype I, 3 (12.5%) to subtype II. BKV belonging to subtypes III or IV were not found. As regards subtype I subgroups, the following were identified: 1 (4.76%) from Ia, 10 (47.61%) from Ib1 and 10 (47.61%) from Ib2. Presence of subgroup Ic was not shown. Viremia presented in 33.33% of cases, whereas 75% corresponded to subgroup Ib 1. Genotype Ib1 is prevailing in Southeast Asia, while Ib2 is prominent in Europe. Although an important proportion of the inhabitants of the province of Buenos Aires are European descendants, the prevailing genotype is Ib1, the Asian type. Genotyping might be related to the evolution of the disease in the recipient.

First epidemiologic study in Argentina of the prevalence of BK viruria in kidney transplant patients.

BACKGROUND: The worldwide seroprevalence of human BK polyomavirus (BKV) in adults is 80%. About 10%-60% of renal transplant recipients experience BKV infection, nephropathy of the graft may occur in 5% of the cases, and up to 45% lose the graft. The aim of this work was to describe the prevalence of BK viruria during the 1st year after transplantation. METHODS: An epidemiologic multicenter cross-sectional study was carried out in consecutive patients at each site with kidney transplantation from August 2011 to July 2012. Clinically significant viruria was defined as >10(7) copies/mL. Viral DNA was extracted with the use of silica columns. Quantification was performed with the use of real-time polymerase chain reaction with primers that amplify a fragment of the large T-antigen gene and with a specific Taqman-MGB probe for BKV. For each assay, a standard curve with a quantified plasmid was included. RESULTS: Of 402 renal transplant recipients at 18 renal transplant sites, we analyzed 382; median age was 46.33 years, and 46.40% were female. The median of the temporal distribution for urine samples was 153 days. BK virus was detected in 50/382 samples (13%), 18 with values >10(7) copies/mL (4.7%). The median of the distribution of positive values was 123 days and the highest frequency of positive values was in months 3-7. The conditions of recipient older than 34 years and donor older than 41 years were the only ones that showed statistically significant association with BK viruria. No association with any specific immunosuppressive drug was observed. CONCLUSIONS: This is the first multicenter study conducted in Argentina to determine the prevalence of BK viruria in renal transplant recipients. Because of the growing number of the population susceptible to this infection, it is important to register and describe data about its epidemiology and associated risk factors.

Pediococcus acidilactici isolated from the rumen of lambs with rumen acidosis, 16S rRNA identification and sensibility to monensin and lasalocid.

A lactic-acid producing bacterium was isolated from the rumen of lambs with rumen acidosis. The cells were gram-positive, nonmotile, nonsporing, catalase negative spherical, 1.5-2.0 µm in diameter, and occur in pairs and tetrads. Analysis of 16S ribosomal RNA indicated that the rumen bacterium was a strain of Pediococcus acidilactici with 99% of nucleotide homology. This bacterium was sensible to monensin and lasalocid at the unique dose tested of 300 ppm. The concentration of lactic acid and DM degradation decreased (P<0.05) when monensin or lasalocid were added to the culture media after 24, 48 and 72 h of incubation. In contrast, total VFA concentration and pH were higher (P<0.05) in the culture media added with the ionophores. Up to now S. bovis is considered the main ruminal bacterium related with rumen acidosis, but the importance of P. acidilactici should be also reconsidered in experimental studies focused on the control rumen acidosis.

The first report of familial adult T-cell leukemia/lymphoma in Argentina.

Here we describe two Caucasian brothers who developed adult T-cell leukemia/lymphoma (ATLL), within a short period of time. These two patients have never left Argentina. Their parents are dead and according to the family history it is possible that the mother may have been affected by spastic paraparesis. The daughters reported that their mother had suffered from increasing difficulty in walking for many years which finally made it impossible for to her walk. There are no other data to support the presumptive diagnosis. One of the patients presented with acute disease while the other had a lymphoma type disorder. Both were positive for HTLV 1. The first patient died with disease progression ten months after diagnosis and the second is in partial remission 13 months after diagnosis. Immunophenotyping showed CD4+, CD5+, CD3+, CD2+, CD8 (-). Two asymptomatic brothers with positive HTLV 1 serology were detected. This is the first family case that has been reported in Argentina.

[A study of left ventricle filling using pulsed Doppler in patients with a high prevalence of atherosclerosis]. / Estudio del llenado ventricular izquierdo con Doppler pulsado en pacientes con prevalencia alta para aterosclerosis.

We studied the left ventricular diastolic function with Doppler Echocardiography in 61 patients: the first group (A) was conformed by 20 patients with cerebral stroke in evolution (24 to 48 hours) with age between (45 to 63 year old) every one had carotid obstructive lesion shown by angiography. The (B) group had 21 patients with ischemic heart disease and all of them had selective coronary arteriography with atheromatous obstructive lesions (45 to 63 years old); 17 of this patients had previous myocardial infarction. The third group (C) was formed by 20 healthy people between 40 and 62 years of age. We found an increase in the late diastolic peak velocity, in the (A/E) ratio in the early diastolic time; in the early diastolic acceleration and in early diastolic desceleration. The difference between groups (A) and (B) with the (C) was evident (P less than 0.001). We conclude that patients of (A) and (B) groups had reduced left ventricular compliance and the (B) group with evidence of ischemic heart disease show more prominent abnormality.

Obstrucción duodenal congénita

Se presentan dos casos de obstrucción duodenal congénita, uno por páncreas anular, operado el 1ro de Mayo de 1960 y el otro de atresia duodenal en su tercera porción, operado el 17 de Junio de 1961. Estos casos constituyen una urgencia quirúrgica, consistiendo su tratamiento operatorio correcto en una duodenoyeyunostomía - transmesocólica - isoperistálica - látero lateral o término lateral. Si no se encuentran otras alteraciones congénitas, el tratamiento quirúrgico resulta en un éxito operatorio, pues la intervención no altera en lo absoluto el desarrollo normal ulterior del niño (AU)