Multiplex preamplification of specific cDNA targets prior to gene expression analysis by TaqMan Arrays

<p>Abstract</p> <p>Background</p> <p>An accurate gene expression quantification using TaqMan Arrays (TA) could be limited by the low RNA quantity obtained from some clinical samples. The novel cDNA preamplification system, the TaqMan PreAmp Master Mix kit (TPAMMK), enables a multiplex preamplification of cDNA targets and therefore, could provide a sufficient amount of specific amplicons for their posterior analysis on TA.</p> <p>Findings</p> <p>A multiplex preamplification of 47 genes was performed in 22 samples prior to their analysis by TA, and relative gene expression levels of non-preamplified (NPA) and preamplified (PA) samples were compared. Overall, the mean cycle threshold (CT) decrement in the PA genes was 3.85 (ranging from 2.07 to 5.01). A high correlation (r) between the gene expression measurements of NPA and PA samples was found (mean r = 0.970, ranging from 0.937 to 0.994; p < 0.001 in all selected cases). High correlation coefficients between NPA and PA samples were also obtained in the analysis of genes from degraded RNA samples and/or low abundance expressed genes.</p> <p>Conclusion</p> <p>We demonstrate that cDNA preamplification using the TPAMMK before TA analysis is a reliable approach to simultaneously measure gene expression of multiple targets in a single sample. Moreover, this procedure was validated in genes from degraded RNA samples and low abundance expressed genes. This combined methodology could have wide applications in clinical research, where scarce amounts of degraded RNA are usually obtained and several genes need to be quantified in each sample.</p

Effect of Glycine on Lead Mobilization, Lead-Induced Oxidative Stress, and Hepatic Toxicity in Rats

The effectiveness of glycine in treating experimental lead intoxication was examined in rats. Male Wistar rats were exposed to 3 g/L lead acetate in drinking water for 5 weeks and treated thereafter with glycine (100 and 500 mg/kg, orally) once daily for 5 days or glycine (1000 mg/kg, orally) once daily for 28 days. The effect of these treatments on parameters indicative of oxidative stress (glutathione and malondialdehyde levels), the activity of blood δ-aminolevulinic acid dehydratase, and lead concentration in blood, liver, kidney, brain, and bone were investigated. Liver samples were observed for histopathological changes. Glycine was found to be effective in (1) increasing glutathione levels; (2) reducing malondialdehyde levels; (3) decreasing lead levels in bone with the highest dose. However, glycine had no effect on lead mobilization when 100 and 500 mg/kg glycine were administered. In microscopic examination, glycine showed a protective effect against lead intoxication

Genetic and demographic recovery of an isolated population of brown bear Ursus arctos L., 1758

The brown bear Ursus arctos L., 1758 population of the Cantabrian Mountains (northwestern Spain) became isolated from other bear populations in Europe about 500 years ago and has declined due to hunting and habitat degradation. At the beginning of the 20th century, the Cantabrian population split into eastern and western subpopulations, and genetic exchange between them ceased. In the early 1990s, total population size was estimated to be < 100 bears. Subsequently, reduction in human-caused mortality has brought about an increase in numbers, mainly in the western subpopulation, likely promoting male-mediated migration and gene flow from the western nucleus to the eastern. To evaluate the possible genetic recovery of the small and genetically depauperate eastern subpopulation, in 2013 and 2014 we genotyped hair and faeces samples (116 from the eastern subpopulation and 36 from the western) for 18 microsatellite markers. Data from the annual count of females with cubs of the year (COY) during the past twenty-six years was used to analyze demographic changes. The number of females with COY fell to a minimum of seven in the western and three in eastern subpopulations in the biennium 1993¿1994 and reached a respective maximum of 54 and 10 individuals in 2013¿2014. We also observed increased bear dispersal and gene flow, mainly from the western to the eastern subpopulation. Of the 26 unique genotypes detected in the eastern subpopulation, 14 (54%) presented an admixture composition, and seven (27%) were determined to be migrants from the western subpopulation. Hence, the two separated and clearly structured subpopulations identified in the past currently show some degree of genetic admixture. This research shows the partial demographic recovery and a change in genetic composition due to migration process in a population of bears that has been isolated for several centuriesPeer Reviewe

HER-2/AKT expression in upper urinary tract urothelial carcinoma: prognostic implications

AIM: To assess HER-2 and p-AKT expression in upper urinary tract urothelial carcinoma (UTUC) in order to determine their value as prognostic factors of tumour progression and cancer-specific survival. PATIENTS AND METHODS: One hundred consecutive UTUC patients were retrospectively included, between 1990-2004, in 4 tissue microarrays for immunostaining. Median follow-up: 33.03 months. RESULTS: Positive HER-2 expression was found in 10 cases and cytoplasmic p-AKT expression in 84 cases; the expression intensity was strong: 30 cases, moderate: 28 and weak: 26. Nuclear p-AKT expression was found in 6 patients: 1 with strong, and 5 with moderate intensity. Nuclear p-AKT expression was an independent factor for tumour progression (HR=4.145, p=0.013), together with grade (HR=4.557, p=0.009) and stage (HR=2.085, p=0.003). In cancer-specific survival analysis, nuclear p-AKT expression (HR=4.268, p=0.017), together with grade (HR=5.214, p=0.035) and stage (HR=2.666, p=0.002) were identified as independent prognostic factors. CONCLUSION: Nuclear p-AKT expression together with stage and grade constitute independent prognostic factors for tumour progression and cancer-specific survival

HER-2/AKT expression in upper urinary tract urothelial carcinoma: prognostic implications

AIM: To assess HER-2 and p-AKT expression in upper urinary tract urothelial carcinoma (UTUC) in order to determine their value as prognostic factors of tumour progression and cancer-specific survival. PATIENTS AND METHODS: One hundred consecutive UTUC patients were retrospectively included, between 1990-2004, in 4 tissue microarrays for immunostaining. Median follow-up: 33.03 months. RESULTS: Positive HER-2 expression was found in 10 cases and cytoplasmic p-AKT expression in 84 cases; the expression intensity was strong: 30 cases, moderate: 28 and weak: 26. Nuclear p-AKT expression was found in 6 patients: 1 with strong, and 5 with moderate intensity. Nuclear p-AKT expression was an independent factor for tumour progression (HR=4.145, p=0.013), together with grade (HR=4.557, p=0.009) and stage (HR=2.085, p=0.003). In cancer-specific survival analysis, nuclear p-AKT expression (HR=4.268, p=0.017), together with grade (HR=5.214, p=0.035) and stage (HR=2.666, p=0.002) were identified as independent prognostic factors. CONCLUSION: Nuclear p-AKT expression together with stage and grade constitute independent prognostic factors for tumour progression and cancer-specific survival

Clinical implications in the shift of syndecan-1 expression from the cell membrane to the cytoplasm in bladder cancer

Background To determine the diagnostic and prognostic capability of urinary and tumoral syndecan-1 (SDC-1) levels in patients with cancer of the urinary bladder. Methods SDC-1 levels were quantitated by enzyme-linked immunosorbent assay (ELISA) in 308 subjects (102 cancer subjects and 206 non-cancer subjects) to assess its diagnostic capabilities in voided urine. The performance of SDC-1 was evaluated using the area under the curve of a receiver operating characteristic curve. In addition, immunohistochemical (IHC) staining assessed SDC-1 protein expression in 193 bladder specimens (185 cancer subjects and 8 non-cancer subjects). Outcomes were correlated to SDC-1 levels. Results Mean urinary levels of SDC-1 did not differ between the cancer subjects and the non-cancer subjects, however, the mean urinary levels of SDC-1 were reduced in high-grade compared to low-grade disease (p < 0.0001), and in muscle invasive bladder cancer (MIBC) compared to non-muscle invasive bladder cancer (NMIBC) (p = 0.005). Correspondingly, preliminary data note a shift from a membranous cellular localization of SDC-1 in normal tissue, low-grade tumors and NMIBC, to a distinctly cytoplasmic localization in high-grade tumors and MIBC was observed in tissue specimens. Conclusion Alone urinary SDC-1 may not be a diagnostic biomarker for bladder cancer, but its urinary levels and cellular localization were associated with the differentiation status of patients with bladder tumors. Further studies are warranted to define the potential role for SDC-1 in bladder cancer progression

Interleukin-1β Modulation of the Mechanobiology of Primary Human Pulmonary Fibroblasts: Potential Implications in Lung Repair

Pro-inflammatory cytokines like interleukin-1β (IL-1β) are upregulated during early responses to tissue damage and are expected to transiently compromise the mechanical microenvironment. Fibroblasts are key regulators of tissue mechanics in the lungs and other organs. However, the effects of IL-1β on fibroblast mechanics and functions remain unclear. Here we treated human pulmonary fibroblasts from control donors with IL-1β and used Atomic Force Microscopy to unveil that IL-1β significantly reduces the stiffness of fibroblasts concomitantly with a downregulation of filamentous actin (F-actin) and alpha-smooth muscle (α-SMA). Likewise, COL1A1 mRNA was reduced, whereas that of collagenases MMP1 and MMP2 were upregulated, favoring a reduction of type-I collagen. These mechanobiology changes were functionally associated with reduced proliferation and enhanced migration upon IL-1β stimulation, which could facilitate lung repair by drawing fibroblasts to sites of tissue damage. Our observations reveal that IL-1β may reduce local tissue rigidity by acting both intracellularly and extracellularly through the downregulation of fibroblast contractility and type I collagen deposition, respectively. These IL-1β-dependent mechanical effects may enhance lung repair further by locally increasing pulmonary tissue compliance to preserve normal lung distension and function. Moreover, our results support that IL-1β provides innate anti-fibrotic protection that may be relevant during the early stages of lung repair

Prognostic value of circulating microRNAs in upper tract urinary carcinoma

The identification of upper tract urinary carcinoma (UTUC) prognostic biomarkers is urgently needed to predict tumour progression. This study aimed to identify serum microRNAs (miRNAs) that may be useful as minimally invasive predictive biomarkers of tumour progression and survival in UTUC patients. To this end, 33 UTUC patients who underwent radical nephroureterectomy at the Hospital Clinic of Barcelona were prospectively included. Expression of 800 miRNAs was evaluated in serum samples from these patients using nCounter® miRNA Expression Assays. The study was divided into an initial discovery phase (n=12) and a validation phase (n=21). Cox regression analysis was used for survival analysis. The median follow-up (range) of the series was 42 months (9-100 months). In the discovery phase, 38 differentially expressed miRNAs were identified between progressing and non-progressing UTUC patients (p<0.05). Validation of these 38 miRNAs in an independent set of UTUC patients confirmed the differential expression in 18 of them (p<0.05). Cox Regression analysis showed miR-151b and pathological stage as significant prognostic factors for tumour progression (HR=0.33, p<0.001 and HR=2.62, p=0.006, respectively) and cancer specific survival (HR=0.25, p<0.001 and HR=3.98, p=0.003, respectively). Survival curves revealed that miR-151b is able to discriminate between two groups of UTUC patients with a highly significant different probability of tumour progression (p=0.006) and cancer specific survival (p=0.034). Although the data needs to be externally validated, miRNA analysis in serum appears to be a valuable prognostic tool in UTUC patients. Particularly, differential expression of miR-151b in serum may serve as a minimally invasive prognostic tool in UTUC

Paravertebral Muscle Mechanical Properties in Patients with Axial Spondyloarthritis or Low Back Pain: A Case-Control Study

Different musculoskeletal disorders are a source of pain in the spinal region; most of them can be divided into mechanical, such as low back pain (LBP), or inflammatory origins, as is the case of axial spondyloarthritis (axSpA). Nevertheless, insufficient information is available about the muscle negative consequences of these conditions. Thus, the objective of this study was to identify whether mechanical muscle properties (MMPs) of cervical and lumbar muscles are different between patients with axSpA, subacute LBP (sLBP), and healthy controls. Furthermore, we aimed identify whether MMPs were related to sociodemographic and clinical variables in various study groups. The MMPs, sociodemographic, and clinical variables were obtained in 43 patients with axSpA, 43 subjects with sLBP, and 43 healthy controls. One-way ANOVAs and ROC curves were applied to identify whether the MMPs could differentiate between the study groups. Intra-group Pearson r coefficients to test the associations between MMPs and the rest of the variables were calculated. The results showed that axSpA subjects have a higher tone and stiffness and a lower relaxation and creep than sLBP and healthy ones (p 0.8). However, no MMP could differentiate between sLBP and healthy subjects. Each group had a different pattern of bivariate correlations between MMPs and sociodemographic and clinical data, with a worse state and progression of the axSpA group associated with a higher tone and stiffness in both spinal regions. This study supports that MMPs are different and show different patterns of correlations depending on the type of spinal pain

La práctica docente como escenario de la unidad entre teoría y práctica en la formación de docentes de la Licenciatura en Educación Secundaria

La presente investigación analiza la unidad entre teoría y práctica en los procesos de la práctica docente en la formación inicial del profesorado de la Licenciatura en Educación Secundaria del Centro de Actualización del Magisterio- Acapulco. El estudio busca esclarecer las conexiones entre la preparación académica de los docentes en formación y el desempeño laboral, el compromiso con los resultados en escuelas de educación básica. Situados en el trayecto de la formación inicial se pretende conocer: ¿Cuál es la mejor manera de aprender a enseñar en la escuela secundaria actualmente? ¿Cómo se puede participar en la innovación del proceso enseñanza aprendizaje para que los adolescentes de la educación secundaria encuentren sentido a lo que aprenden y sean capaces de mejorarse a sí mismos y su entorno vital? Se planteó para su desarrollo una metodología cualitativa interpretativa, retomando instrumentos de carácter cuantitativo. Se construyeron tres categorías de análisis: a) los estándares de desempeño docente, b) la investigación hecha por docentes en formación y c) el enfoque sistémico en el análisis de la práctica docente para darle rigurosidad y hacer visible la interdependencia de factores y actores. Los resultados esclarecen que impactar en la mejora de la formación de docentes implica asumir el reto de la complementariedad y la alternancia de la formación entre el Centro y las instituciones de educación básica. Apostar a los espacios híbridos donde se dé la simbiosis teoría- práctica. Las encuestas aplicadas nos señalan que el manejo del tiempo y la regulación disciplinaria del grupo, la significatividad y relevancia de las actividades de aprendizaje, así como el diseño de materiales potencialmente significativos, atrayentes y útiles, constituyen la preocupación central de los candidatos a docentes; pero se devela, queal parecer, tienen que ver con el conocimiento que se tiene de los alumnos, el saber cómo aprenden y un dominio mejor de la asignatura que imparten