37 research outputs found

    Comparison of washing methods and smear conservation periods for llama sperm acrosome assessment using the Coomassie blue stain

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    El objetivo de este trabajo fue comparar métodos de lavado y conservación de frotis para evaluar el acrosoma en espermatozoides de llama mediante la tinción con Coomassie Blue (CB), con el propósito de facilitar la técnica e independizar los momentos de la extracción de semen de la evaluación de los acrosomas espermáticos. Se procesaron 12 eyaculados, se probaron dos tipos de lavado de los frotis fijados (con PBS o solución fisiológica, SF) y se evaluaron diferentes temperaturas (5º C y temperatura ambiente) y tiempos (0, 1 y 7 días) de conservación. Se evaluaron los siguientes frotis (cada uno lavado con PBS o con SF): 1) fijados, teñidos y evaluados el mismo día de la extracción; 2) fijados, teñidos y conservados 24 hs a temperatura ambiente y luego evaluados; 3) fijados, conservados a 4º C durante 1 día y luego teñidos y evaluados; 4) fijados, conservados a 4º C durante 7 días y luego teñidos y evaluados. Se evaluaron un total de 8 frotis por eyaculado. No se observaron diferencias significativas en el porcentaje de acrosomas presentes evaluado por CB entre las dos metodologías de lavado de los frotis fijados, ni entre las diferentes temperaturas y los diferentes tiempos de conservación de los frotis. Conclusión: es posible utilizar solución fisiológica para lavar los frotis fijados facilitando la técnica de CB para evaluar la presencia de los acrosomas en espermatozoides de llama. Además, se logró independizar los momentos de la extracción de semen de la evaluación de los acrosomas espermáticos.The objective of this study was to compare washing methods and smear conservation periods for llama sperm acrosome assessment using the Coomassie Blue stain, with the aim of facilitating the technique and to allow the moment of sperm acrosome evaluation become independent of the moment of semen collection. Twelve ejaculates were processed; two types of washing of the smears (with PBS or with physiologic solution, PS) and different temperatures (5 ºC and room temperature) and periods of conservation (0, 1 and 7 days) were assessed. The following smears were evaluated: 1) fixed, stained and evaluated the same day of collection; 2) fixed, stained and conserved for 24 hours at room temperature and then evaluated; 3) fixed, conserved at 4º C for 1 day and then stained and evaluated and 4) fixed, conserved at 4º C for 7 days and then stained and evaluated. A total of 8 smears per ejaculate were evaluated. No significant differences were observed in the percentages of acrosomes present, evaluated by CB, between both types of washing of the fixed smears, nor between the different temperatures and conservation periods of the fixed smears. Conclusions: it is possible to use physiologic solution to wash the fixed smears, thus facilitating the Coomassie Blue technique used to evaluate the presence of llama sperm acrosomes. In addition, it was possible to separate the moment of sperm acrosome evaluation from the semen collection.Fil: Fumuso, Fernanda Gabriela. Universidad de Buenos Aires. Facultad de Cs.veterinarias. Area de Teriogenologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gimenez, M. L.. Universidad de Buenos Aires. Facultad de Cs.veterinarias. Area de Teriogenologia; ArgentinaFil: Neild, Debora Margarita. Universidad de Buenos Aires. Facultad de Cs.veterinarias. Area de Teriogenologia; ArgentinaFil: Giuliano, Susana María. Universidad de Buenos Aires. Facultad de Cs.veterinarias. Area de Teriogenologia; ArgentinaFil: Chaves, M. G.. Universidad de Buenos Aires. Facultad de Cs.veterinarias. Area de Teriogenologia; ArgentinaFil: Carretero, Maria Ignacia. Universidad de Buenos Aires. Facultad de Cs.veterinarias. Area de Teriogenologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Combinatory effect of BRCA1 and HERC2 expression on outcome in advanced non-small-cell lung cancer

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    BACKGROUND: BRCA1 is a main component of homologous recombination and induces resistance to platinum in preclinical models. It has been studied as a potential predictive marker in lung cancer. Several proteins modulate the function of BRCA1. The E3 ubiquitin ligase HERC2 facilitates the assembly of the RNF8-UBC13 complex to recruit BRCA1 to DNA damage sites. The combined analysis of multiple components of the pathway leading to the recruitment of BRCA1 at DNA damage sites has the potentiality to improve the BRCA1 predictive model. METHODS: We retrospectively analyzed 71 paraffin-embedded tumor samples from advanced non-small-cell lung cancer patients treated with first-line platinum based chemotherapy and measured the mRNA expression levels of BRCA1, RNF8, UBC13 and HERC2 using real-time PCR. The mRNA expression was categorized using median value as cut-off point. RESULTS: The median progression-free survival of all 71 patients was 7.2 months whereas the median overall survival of the study population was 10.7 months. Among patients with low BRCA1 expression, the median PFS was 7.4 months in the presence of low HERC2 levels and 5.9 months for patients expressing high HERC2 levels (p\u2009=\u20090.01). The median OS was 15.3 months for patients expressing low levels of both genes and 7.4 months for those with low BRCA1 but high HERC2 (p\u2009=\u20090.008). The multivariate analysis showed that among patients with Eastern Cooperative Oncology Group performance status 0-1, the combined low expression of both BRCA1 and HERC2 clearly reduced the risk of progression (p\u2009=\u20090.03) and of death (p\u2009=\u20090.004). CONCLUSIONS: These findings confirm the potentiality of integrated DNA repair components analysis in predicting the sensitivity to platinum in lung cancer. The study indicates a predictive role for HERC2 mRNA expression and paves the way for further refinement of the BRCA1 predictive model

    BRCA1, LMO4, and CtIP mRNA Expression in Erlotinib-Treated Non–Small-Cell Lung Cancer Patients with EGFR Mutations

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    IntroductionLung adenocarcinoma patients harboring EGFR activating mutations attain improved progression-free survival (PFS) with treatment with epidermal growth factor receptor tyrosine kinase inhibitors. However, patients ultimately relapse, indicating that other genetic factors could influence outcome in such patients. We hypothesized that PFS could be influenced by the expression of genes in DNA repair pathways.MethodsWe examined the mRNA expression of C terminus-binding protein–interacting protein and Lin11, Isl-1, and Mec-3 domain only 4 (LMO4) in pretreatment tumor samples from 91 erlotinib-treated advanced non–small-cell lung cancer patients with EGFR mutations in whom breast cancer gene 1 (BRCA1) expression and the concomitant presence of the EGFR T790M mutation had previously been assessed. Gene expression was analyzed by polymerase chain reaction, using β-actin as endogenous gene. Results were correlated with PFS and overall survival.ResultsIn patients with low LMO4 levels, PFS was 13 months, whereas it was not reached for those with high LMO4 levels (p = 0.03). In patients with low levels of both BRCA1 and LMO4, PFS was 19 months whereas it was not reached in those with low BRCA1 and high LMO4 mRNA levels (p = 0.04). In patients with high BRCA1 and low LMO4 levels, PFS was 8 months, whereas it was 18 months in those with high levels of both genes (p = 0.03).ConclusionsLow BRCA1 and high LMO4 levels were associated with longer PFS to erlotinib. Baseline assessment of BRCA1 and LMO4 mRNA expression can help predict outcome to erlotinib

    Multiplex Real-Time PCR Assay Using TaqMan Probes for the Identification of Trypanosoma cruzi DTUs in Biological and Clinical Samples

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    Background: Trypanosoma cruzi has been classified into six Discrete Typing Units (DTUs), designated as TcI–TcVI. In order to effectively use this standardized nomenclature, a reproducible genotyping strategy is imperative. Several typing schemes have been developed with variable levels of complexity, selectivity and analytical sensitivity. Most of them can be only applied to cultured stocks. In this context, we aimed to develop a multiplex Real-Time PCR method to identify the six T. cruzi DTUs using TaqMan probes (MTq-PCR).Methods/Principal Findings: The MTq-PCR has been evaluated in 39 cultured stocks and 307 biological samples from vectors, reservoirs and patients from different geographical regions and transmission cycles in comparison with a multi-locus conventional PCR algorithm. The MTq-PCR was inclusive for laboratory stocks and natural isolates and sensitive for direct typing of different biological samples from vectors, reservoirs and patients with acute, congenital infection or Chagas reactivation. The first round SL-IR MTq-PCR detected 1 fg DNA/reaction tube of TcI, TcII and TcIII and 1 pg DNA/reaction tube of TcIV, TcV and TcVI reference strains. The MTq-PCR was able to characterize DTUs in 83% of triatomine and 96% of reservoir samples that had been typed by conventional PCR methods. Regarding clinical samples, 100% of those derived from acute infected patients, 62.5% from congenitally infected children and 50% from patients with clinical reactivation could be genotyped. Sensitivity for direct typing of blood samples from chronic Chagas disease patients (32.8% from asymptomatic and 22.2% from symptomatic patients) and mixed infections was lower than that of the conventional PCR algorithm.Conclusions/Significance: Typing is resolved after a single or a second round of Real-Time PCR, depending on the DTU. This format reduces carryover contamination and is amenable to quantification, automation and kit production.This work received financial support from the Ministry of Science and Technology of Argentina [PICT 2011-0207 to AGS] and the National Scientific and Technical Research Council in Argentina (CONICET) [PIP 112 2011-010-0974 to AGS]. Work related to evaluation of biological samples was partially sponsored by the Pan-American Health Organization (PAHO) [Small Grants Program PAHO-TDR]; the Drugs and Neglected Diseases Initiative (DNDi, Geneva, Switzerland), Wellcome Trust (London, United Kingdom), SANOFI-AVENTIS (Buenos Aires, Argentina) and the National Council for Science and Technology in Mexico (CONACYT) [FONSEC 161405 to JMR]

    Risk factors for infections caused by carbapenem-resistant Enterobacterales: an international matched case-control-control study (EURECA)

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    Cases were patients with complicated urinary tract infection (cUTI), complicated intraabdominal (cIAI), pneumonia or bacteraemia from other sources (BSI-OS) due to CRE; control groups were patients with infection caused by carbapenem-susceptible Enterobacterales (CSE), and by non-infected patients, respectively. Matching criteria included type of infection for CSE group, ward and duration of hospital admission. Conditional logistic regression was used to identify risk factors. Findings Overall, 235 CRE case patients, 235 CSE controls and 705 non-infected controls were included. The CRE infections were cUTI (133, 56.7%), pneumonia (44, 18.7%), cIAI and BSI-OS (29, 12.3% each). Carbapenemase genes were found in 228 isolates: OXA-48/like, 112 (47.6%), KPC, 84 (35.7%), and metallo-beta-lactamases, 44 (18.7%); 13 produced two. The risk factors for CRE infection in both type of controls were (adjusted OR for CSE controls; 95% CI; p value) previous colonisation/infection by CRE (6.94; 2.74-15.53; <0.001), urinary catheter (1.78; 1.03-3.07; 0.038) and exposure to broad spectrum antibiotics, as categorical (2.20; 1.25-3.88; 0.006) and time-dependent (1.04 per day; 1.00-1.07; 0.014); chronic renal failure (2.81; 1.40-5.64; 0.004) and admission from home (0.44; 0.23-0.85; 0.014) were significant only for CSE controls. Subgroup analyses provided similar results. Interpretation The main risk factors for CRE infections in hospitals with high incidence included previous coloni-zation, urinary catheter and exposure to broad spectrum antibiotics

    Fibrous clays based bionanocomposites

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