FRECUENCIA DE RABDOMIOSARCOMA CANINO EN EL LABORATORIO DE HISTOPATOLOGÍA VETERINARIA DE LA UNIVERSIDAD NACIONAL MAYOR DE SAN MARCOS (PERIODO 2000-2008)

The purpose of this study was to determine the frequency of canine rhabdomyosarcoma based on its histopathological classification, that were diagnosed in the histopathology laboratory of the Veterinary Faculty of San Marcos University, Lima, Peru in the period of January 2000 to December 2008. A total of 63 cases of canine rhabdomyosarcoma were diagnosed out of 1125 canine neoplasic tumors (5.6 ± 1.3%). Among this, only 47 cases were possible to classify where 27 cases (57.4%) corresponded to embryonal rhabdomyosarcoma, 19 (40.4%) to alveolar rhabdomyosarcoma, and one case (2.1%) to pleomorphic rhabdomyosarcoma. The most frequent region of the body affected by the embryonal type was the head and neck, where 6 to 10 year-old animals were the most affected.El objetivo del presente estudio fue determinar la frecuencia del rabdomiosarcoma canino, según su clasificación histopatológica, diagnosticado en el laboratorio de histopatología de la Facultad de Medicina Veterinaria de la Universidad Nacional Mayor de San Marcos, Lima, Perú, en el periodo de enero de 2000 a diciembre de 2008. Fueron diagnosticados 63 casos de rabdomiosarcoma canino dentro de un total de 1125 casos de neoplasias caninas (5.6 ± 1.3%). De estos, sólo 47 casos pudieron ser clasificados, donde 27 casos (57.4%) correspondieron a rabdomiosarcomas embrionarios, 19 (40.4%) a rabdomiosarcomas alveolares y un caso (2.1%) a rabdomiosarcoma pleomórfico. La región de mayor frecuencia de presentación para el tipo embrionario fue la cabeza y el cuello, siendo los canes de 6 a 10 años los más afectados

Detección de Salmonella sp en Carcasas Porcinas en Camales de Lima, Perú

The aim of this study was to detect the frequency of Salmonella sp by isolation techniques in pork carcasses intended for human consumption. Three hundred carcasses from two slaughterhouses in Lima, Peru were studied. Samples were taken by swabbing the skin of the head, abdomen, back and leg, representing 1200 subsamples. They were taken to the laboratory in Falcon tubes with buffered peptone water, and processed following the protocol for isolation of bacteria based on ISO 6579:2002. The isolates were identified by biochemical tests and specific antisera. In 6.3 ± 2.4% (19/300) of carcasses and 1.8% (21/1200) of subsamples were detected Salmonella sp. The highest frequencies of isolates were obtained from the head (33.3%, 7/21) and the abdomen (33.3%, 7/21). The isolates were serotyped and identified as Salmonella enterica subesp. enterica serotype Derby. The results confirm the need to implement control measures and detection of the bacteria to reduce the frequency of contaminated pork that reaches the consumer.El objetivo del presente estudio fue detectar la frecuencia de Salmonella sp, mediante técnicas de aislamiento, en carcasas porcinas destinadas al consumo humano. Se muestrearon 300 carcasas beneficiadas en dos camales de Lima Metropolitana, Perú. Las muestras fueron tomadas mediante hisopados sobre la piel de la cabeza, vientre, lomo y pierna, representando en total 1200 submuestras. Estas fueron transportadas al laboratorio en tubos Falcon con agua peptonada tamponada, donde fueron procesadas, siguiendo el protocolo de aislamiento bacteriano basado en la norma ISO 6579:2002. Los aislados fueron identificados mediante pruebas bioquímicas y antisueros específicos. En el 6.3 ± 2.4% (19/300) de las carcasas y en 1.8% (21/1200) de las submuestras se detectó la presencia de Salmonella sp. El mayor porcentaje de aislados se obtuvo de la piel de la cabeza (33.3%, 7/21) y vientre (33.3%, 7/21). Los aislados fueron serotipificados e identificados como Salmonella enterica subesp. enterica serotipo Derby. Los resultados confirman la necesidad de implementar medidas de control y detección de la bacteria que permitan reducir la frecuencia de carne de cerdo contaminada que llega al consumidor

Radial decoupling of small and large dust grains in the transitional disk RX J1615.3-3255

We present H-band (1.6 {\mu}m) scattered light observations of the transitional disk RX J1615.3-3255, located in the ~1 Myr old Lupus association. From a polarized intensity image, taken with the HiCIAO instrument of the Subaru Telescope, we deduce the position angle and the inclination angle of the disk. The disk is found to extend out to 68 $\pm$ 12 AU in scattered light and no clear structure is observed. Our inner working angle of 24 AU does not allow us to detect a central decrease in intensity similar to that seen at 30 AU in the 880 {\mu}m continuum observations. We compare the observations with multiple disk models based on the Spectral Energy Distribution (SED) and submm interferometry and find that an inner rim of the outer disk at 30 AU containing small silicate grains produces a polarized intensity signal which is an order of magnitude larger than observed. We show that a model in which the small dust grains extend smoothly into the cavity found for large grains is closer to the actual H-band observations. A comparison of models with different dust size distributions suggests that the dust in the disk might have undergone significant processing compared to the interstellar medium.Comment: 8 pages, 7 figures, 4 tables. Accepted for publication in A&

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Purine Biosynthesis in Chinese Hamster Cell Mutants and Human Fibroblasts Partially Deficient in Adenylosuccinate Lyase

Adenylosuccinate lyase (ASMP lyase, EC4.3.2.2) is the terminal enzyme j in de novo adenylate synthesis and as such acts to convert adenylosuccinate (AS) monophosphate to adenosine monophosphate. This enzyme also participates in the de novo synthesis of IMP converting 5′-phosphoribosyl-4-(N-succino carboxamide)-5-aminoimidazole (SAICAR) to 5′-phosphoribosyl-5-amino-4-imidazolecarboxamide (AICAR). Recently Jaeken, et al. described three patients with neurologic dysfunctions including infantile autism syndrome (1) who had elevated levels of AS and a compound tentatively identified as SAICA riboside in urine, blood, and cerebral spinal fluid. These patients have a markedly decreased but varying activity of ASMP lyase in various tissues studied. Deficiency of ASMP lyase has previously been described in mutagenized and nutrient-selected Chinese Hamster Ovary fibroblasts (CHO-Ade I cells) (2,3). These cells excrete excess ASMP and SAICAR into the culture medium. In the present study of purine nucleotide metabolism of CHO-Ade I cells and fibroblasts from a AS and SAICA riboside over-producing patient we examined the effect of ASMP lyase deficiency on branchpoint enzyme activities and on de novo synthesis by comparison to the control cell lines, wild type parent cells (CHO-K1) and fibroblasts from age-matched normal individuals, respectively

Medium-Chain Acyl-CoA Dehydrogenase (MCAD) Mutations Identified by MS/MS-Based Prospective Screening of Newborns Differ from Those Observed in Patients with Clinical Symptoms: Identification and Characterization of a New, Prevalent Mutation That Results in Mild MCAD Deficiency

Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is the most frequently diagnosed mitochondrial β-oxidation defect, and it is potentially fatal. Eighty percent of patients are homozygous for a common mutation, 985A→G, and a further 18% have this mutation in only one disease allele. In addition, a large number of rare disease-causing mutations have been identified and characterized. There is no clear genotype-phenotype correlation. High 985A→G carrier frequencies in populations of European descent and the usual avoidance of recurrent disease episodes by patients diagnosed with MCAD deficiency who comply with a simple dietary treatment suggest that MCAD deficiency is a candidate in prospective screening of newborns. Therefore, several such screening programs employing analysis of acylcarnitines in blood spots by tandem mass spectrometry (MS/MS) are currently used worldwide. No validation of this method by mutation analysis has yet been reported. We investigated for MCAD mutations in newborns from US populations who had been identified by prospective MS/MS-based screening of 930,078 blood spots. An MCAD-deficiency frequency of 1/15,001 was observed. Our mutation analysis shows that the MS/MS-based method is excellent for detection of MCAD deficiency but that the frequency of the 985A→G mutant allele in newborns with a positive acylcarnitine profile is much lower than that observed in clinically affected patients. Our identification of a new mutation, 199T→C, which has never been observed in patients with clinically manifested disease but was present in a large proportion of the acylcarnitine-positive samples, may explain this skewed ratio. Overexpression experiments showed that this is a mild folding mutation that exhibits decreased levels of enzyme activity only under stringent conditions. A carrier frequency of 1/500 in the general population makes the 199T→C mutation one of the three most prevalent mutations in the enzymes of fatty-acid oxidation

Common Genetic Variants Associated with Resting Oxygenation in Chronic Obstructive Pulmonary Disease.

Hypoxemia is a major complication of chronic obstructive pulmonary disease (COPD) that correlates with disease prognosis. Identifying genetic variants associated with oxygenation may provide clues for deciphering the heterogeneity in prognosis among patients with COPD. However, previous genetic studies have been restricted to investigating COPD candidate genes for association with hypoxemia. To report results from the first genome-wide association study (GWAS) of resting oxygen saturation (as measured by pulse oximetry [Sp(o(2))]) in subjects with COPD, we performed a GWAS of Sp(o(2)) in two large, well characterized COPD populations: COPDGene, including both the non-Hispanic white (NHW) and African American (AA) groups, and Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE). We identified several suggestive loci (P < 1 × 10(−5)) associated with Sp(o(2)) in COPDGene in the NHW (n = 2810) and ECLIPSE (n = 1758) groups, and two loci on chromosomes 14 and 15 in the AA group (n = 820) from COPDGene achieving a level of genome-wide significance (P < 5 × 10(−8)). The chromosome 14 single-nucleotide polymorphism, rs6576132, located in an intergenic region, was nominally replicated (P < 0.05) in the NHW group from COPDGene. The chromosome 15 single-nucleotide polymorphisms were rare in subjects of European ancestry, so the results could not be replicated. The chromosome 15 region contains several genes, including TICRR and KIF7, and is proximal to RHCG (Rh family C glyocoprotein gene). We have identified two loci associated with resting oxygen saturation in AA subjects with COPD, and several suggestive regions in subjects of European descent with COPD. Our study highlights the importance of investigating the genetics of complex traits in different racial groups

Common Genetic Variants Associated with Resting Oxygenation in Chronic Obstructive Pulmonary Disease

Hypoxemia is a major complication of chronic obstructive pulmonary disease (COPD) that correlates with disease prognosis. Identifying genetic variants associated with oxygenation may provide clues for deciphering the heterogeneity in prognosis among patients with COPD. However, previous genetic studies have been restricted to investigating COPD candidate genes for association with hypoxemia. To report results from the first genome-wide association study (GWAS) of resting oxygen saturation (as measured by pulse oximetry [Spo2]) in subjects with COPD, we performed a GWAS of Spo2 in two large, well characterized COPD populations: COPDGene, including both the non-Hispanic white (NHW) and African American (AA) groups, and Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE). We identified several suggestive loci (P &lt; 1 × 10(-5)) associated with Spo2 in COPDGene in the NHW (n = 2810) and ECLIPSE (n = 1758) groups, and two loci on chromosomes 14 and 15 in the AA group (n = 820) from COPDGene achieving a level of genome-wide significance (P &lt; 5 × 10(-8)). The chromosome 14 single-nucleotide polymorphism, rs6576132, located in an intergenic region, was nominally replicated (P &lt; 0.05) in the NHW group from COPDGene. The chromosome 15 single-nucleotide polymorphisms were rare in subjects of European ancestry, so the results could not be replicated. The chromosome 15 region contains several genes, including TICRR and KIF7, and is proximal to RHCG (Rh family C glyocoprotein gene). We have identified two loci associated with resting oxygen saturation in AA subjects with COPD, and several suggestive regions in subjects of European descent with COPD. Our study highlights the importance of investigating the genetics of complex traits in different racial groups