907 resultados para marker switch


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Developing a robust method to study characteristics of vascular flow using ultrasound may be useful to assess endothelial function and vasodilatation. There are four stages in this proposal. 1.The first stage is to standardise and validate the methodology to enable computational risk flow data and other flow characteristics to be used clinically. (Current Study). Further development of fluid modelling methods will enable particulate haemodynamics to be investigated, and incorporate detailed endothelial structure together with cellular pathways. 2. This should be followed up by studies in different patient groups investigating the association between the derived values and estimated risk (using other methods such as Framingham risk score). 3. Then, associated with underlying cardiovascular risk, prospective studies would be made to establish whether computational flow dynamic data can predict outcome. If successful it could prove to be a very useful marker of benefit following treatment in a clinical setting.

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Background: Hirschsprung’s disease (HD) is a congenital intestinal motility disorder with absence of ganglion cells in the colonic wall. Diagnosis of the disease is mainly based on the identification of the lack of ganglion cells in the pathology sections of the colon which is very difficult and time consuming and also needs several serial cut sections. There are many proposed markers in this field in the literature but none of them has been satisfactory. Calretinin immunohistochemistry (IHC) has been introduced as a new diagnostic marker to overcome the problems in diagnosis of this disease about 5 years ago. However there are few studies regarding the benefits and pitfalls of this marker. Objectives: The aim of this study is to determine the diagnostic value of calretinin IHC in detecting aganglionosis (HD). Patients and Methods: 27 HD patients and 28 non-Hirschsprung’s disease (NHD) patients were collected in a prospective study and calretinin IHC was performed on 31 aganglionic and 51 normoganglionic full wall thickness sections of colectomies (some of the cases had more than 1 section). The IHC slides were evaluated by two pathologists and the diagnostic value was calculated in comparison with gold standard which is the presence or absence of ganglion cells in serial Hematoxylin and Eosin (HE) stained sections of the colectomies. Results: There was great concordance between the final diagnosis of both pathologists and gold standard (k > 0.9). Calretinin immunostaining showed 100% specificity and positive predictive value and more than 90% sensitivity and negative predictive value. High agreement was present between the two pathologists (k > 0.9). Conclusions: Calretinin IHC is a very convenient, useful and valuable method to demonstrate aganglionosis in HD patients. Loss of calretinin immunostaining in lamina propria and submucosa is characteristic of HD.

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Background: Perinatal asphyxia is an important cause of mortality and permanent neurological and developmental deficit. Early and accurate diagnosis would help to establish the likely prognosis and may also help in determining the most appropriate treatment. Studies in experimental animal models suggest that a protein called Hsp70 may be a good and potentially useful marker of cellular stress that may be clinically useful in determining the presence of neonatal asphyxia. Objectives: Regarding the importance of early and accurate diagnosis of asphyxia, we conducted this study, which is the first investigation of the comparison of the serum Hsp70 antigen level between asphyxiated and healthy infants. Patients and Methods: In this observational study, the serum concentrations of Hsp70 antigen were compared between neonates suffering from perinatal asphyxia (n = 50) and normal neonates (n = 51). The inclusion criteria for the cases were neonates who had reached term and had at least two clinical criteria of asphyxia. Exclusion criteria were babies with gestational age < 37 weeks, infants with congenital abnormalities or positive blood culture. Exclusion criteria in this group were the requirement to hospital stay during first week of the life or babies whose mothers had difficulties during pregnancy or delivery. Term neonates without major anomalies who had asphyxia during delivery were enrolled in the first six hours after delivery, and control group consisted of healthy term neonates without problems and normal delivery process in the first week of life. The cord blood was taken during labor to measure Hsp70 antigen level by using an in-house ELISA (The enzyme-linked immunosorbent assay). Results: The median values of serum anti Hsp70 titers were significantly higher in asphyxiated neonates compared with non-asphyxiated neonates (0.36 [0.04 - 1.14] vs 0.24 [0.01 - 0.63]). At cutoff point = 0.3125 ng/mL, sensitivity was 58% and specificity 76% based on ROC curve. Conclusions: A significant difference between the serum concentrations of Hsp70 of the control and patient group was observed in this study. It is inferred serum concentrations of Hsp70 antigen may be a useful marker for the early diagnosis of that prenatal hypoxia.

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The establishment of a specific Marker-Assisted Selection Facility at the Embrapa Rice and Beans Biotechnology Laboratory, in 2014, has better supported the routine analysis with molecular markers demanded by the Embrapa Common Bean Breeding Program. In addition, it has also supported other Embrapa plant breeding programs, such as rice and cotton.

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Cardiovascular disease is one of the leading causes of death around the world. Resting heart rate has been shown to be a strong and independent risk marker for adverse cardiovascular events and mortality, and yet its role as a predictor of risk is somewhat overlooked in clinical practice. With the aim of highlighting its prognostic value, the role of resting heart rate as a risk marker for death and other adverse outcomes was further examined in a number of different patient populations. A systematic review of studies that previously assessed the prognostic value of resting heart rate for mortality and other adverse cardiovascular outcomes was presented. New analyses of nine clinical trials were carried out. Both the original and extended Cox model that allows for analysis of time-dependent covariates were used to evaluate and compare the predictive value of baseline and time-updated heart rate measurements for adverse outcomes in the CAPRICORN, EUROPA, PROSPER, PERFORM, BEAUTIFUL and SHIFT populations. Pooled individual patient meta-analyses of the CAPRICORN, EPHESUS, OPTIMAAL and VALIANT trials, and the BEAUTIFUL and SHIFT trials, were also performed. The discrimination and calibration of the models applied were evaluated using Harrell’s C-statistic and likelihood ratio tests, respectively. Finally, following on from the systematic review, meta-analyses of the relation between baseline and time-updated heart rate, and the risk of death from any cause and from cardiovascular causes, were conducted. Both elevated baseline and time-updated resting heart rates were found to be associated with an increase in the risk of mortality and other adverse cardiovascular events in all of the populations analysed. In some cases, elevated time-updated heart rate was associated with risk of events where baseline heart rate was not. Time-updated heart rate also contributed additional information about the risk of certain events despite knowledge of baseline heart rate or previous heart rate measurements. The addition of resting heart rate to the models where resting heart rate was found to be associated with risk of outcome improved both discrimination and calibration, and in general, the models including time-updated heart rate along with baseline or the previous heart rate measurement had the highest and similar C-statistics, and thus the greatest discriminative ability. The meta-analyses demonstrated that a 5bpm higher baseline heart rate was associated with a 7.9% and an 8.0% increase in the risk of all-cause and cardiovascular death, respectively (both p less than 0.001). Additionally, a 5bpm higher time-updated heart rate (adjusted for baseline heart rate in eight of the ten studies included in the analyses) was associated with a 12.8% (p less than 0.001) and a 10.9% (p less than 0.001) increase in the risk of all-cause and cardiovascular death, respectively. These findings may motivate health care professionals to routinely assess resting heart rate in order to identify individuals at a higher risk of adverse events. The fact that the addition of time-updated resting heart rate improved the discrimination and calibration of models for certain outcomes, even if only modestly, strengthens the case that it be added to traditional risk models. The findings, however, are of particular importance, and have greater implications for the clinical management of patients with pre-existing disease. An elevated, or increasing heart rate over time could be used as a tool, potentially alongside other established risk scores, to help doctors identify patient deterioration or those at higher risk, who might benefit from more intensive monitoring or treatment re-evaluation. Further exploration of the role of continuous recording of resting heart rate, say, when patients are at home, would be informative. In addition, investigation into the cost-effectiveness and optimal frequency of resting heart rate measurement is required. One of the most vital areas for future research is the definition of an objective cut-off value for the definition of a high resting heart rate.

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Un nuovo marcatore per l'identificazione rapida del sesso del cervo (Cervus elaphus). Il cervo (Cervus elaphus) è una specie cacciabile economicamente importante che risente di alcuni problemi di conservazione. La conoscenza di parametri di popolazione come il rapporto sessi è importante per la sua gestione e conservazione. In questo studio, utilizzando condizioni poco specifiche per l’amplificazione di un frammento del cromosoma Y già descritto in precedenza, descriviamo un metodo che permette una rapida e corretta identificazione del sesso in questa specie, producendo due amplicons diversi nei maschi e uno nelle femmine. I due frammenti, diversi per il peso molecolare, sono facilmente separabili mediante elettroforesi in gel di agarosio, permettendo l'identificazione del sesso con un unico test in campioni biologici come carcasse, embrioni recuperati da femmine abbattute e, forse, peli o escrementi (se la qualità del DNA è accettabile). Questo metodo può essere di aiuto in studi sul rapporto sessi degli embrioni, sulla mortalità associata al sesso o sul rapporto sessi in popolazioni selvatiche o semiselvatiche, con ricadute applicative per le analisi demografiche, la gestione venatoria e la conservazione

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Nelore is the major beef cattle breed in Brazil with more than 130 million heads. Genome-wide association studies (GWAS) are often used to associate markers and genomic regions to growth and meat quality traits that can be used to assist selection programs. An alternative methodology to traditional GWAS that involves the construction of gene network interactions, derived from results of several GWAS is the AWM (Association Weight Matrices)/PCIT (Partial Correlation and Information Theory). With the aim of evaluating the genetic architecture of Brazilian Nelore cattle, we used high-density SNP genotyping data (~770,000 SNP) from 780 Nelore animals comprising 34 half-sibling families derived from highly disseminated and unrelated sires from across Brazil. The AWM/PCIT methodology was employed to evaluate the genes that participate in a series of eight phenotypes related to growth and meat quality obtained from this Nelore sample.