Leukocyte telomere length as potential biomarker of HD progression: A follow-up study

The identification of biomarkers for neurodegenerative disorders such as Huntington's disease (HD) is crucial for monitoring disease progression and therapeutic trial outcomes, especially in the pre-manifest disease stage (pre-HD). In a previous study, we observed that leukocyte telomere length (LTL) was strongly correlated with the estimated time to clinical onset in pre-HD subjects. To validate this hypothesis, we designed a follow-up study in which we analyzed LTL in 45 pre-HD stage subjects at baseline (T0) and then again after clinical onset at follow-up (T1); the follow-up interval was about 3 years, and the CAG range was 39-51 repeats; 90 peripheral blood mononuclear cell samples (PBMCs) were obtained from the Enroll-HD biorepository. In pre-HD subjects at T0, LTL was significantly reduced by 22% compared to the controls and by 14% from T0 at T1. No relationship was observed between the LTL and CAG numbers in subjects carrying different CAG repeats at T0 and at T1, suggesting that LTL reduction occurs independently of CAG number in pre-HD subjects. ROC curve analysis was used to test the validity of LTL as a potential biomarker of HD progression and showed that LTL measurement is extremely accurate in discriminating pre-HD subjects from the controls and even pre-HD from manifest HD, thus yielding a robust prognostic value in pre-HD subjects

ProNGF Is a Cell-Type-Specific Mitogen for Adult Hippocampal and for Induced Neural Stem Cells

The role of proNGF, the precursor of Nerve Growth Factor (NGF), on the biology of adult neural stem cells (aNSCs) is still unclear. Here I analyzed adult hippo-campal neurogenesis in AD11 transgenic mice, in which the constitutive expression of anti-NGF antibody leads to an imbalance of proNGF over mature NGF. I found in-creased proliferation of progenitors but a reduced neurogenesis in the AD11 DG- hippocampus (HP-DG). Also in vitro, AD11 hippocampal neural stem cells (NSCs) pro-liferated more but were unable to differentiate into morphologically mature neu-rons. By treating wild-type (WT) hippocampal progenitors with the uncleavable form of proNGF (proNGF-KR) I demonstrated that proNGF acts as mitogen on aNSCs at low concentration. The mitogenic effect of proNGF was specifically addressed to the radial glia-like (RGL) neural stem cells through the induction of cyclin D1 expression. These cells express high level of p75NTR, as demonstrated by immunofluorescence analyses performed ex vivo on RGL cells isolated from freshly-dissociated HP-DG or selected in vitro from NSCs by LIF (leukemia inhibitory factor). Clonogenic assay per-formed in the absence of mitogens showed that RGLs respond to proNGF-KR by re-activating their proliferation and thus leading to neurospheres formation. The mito-genic effect of proNGF was further exploited in the expansion of mouse induced Neural Stem Cells (iNSCs). Chronic exposure of iNSCs to proNGF-KR increased their proliferation. Altogether, I demonstrated that proNGF acts as mitogen on hippo-campal and induced neural stem cells.The role of proNGF, the precursor of nerve growth factor (NGF), in the biology of adult neural stem cells (aNSCs) is still unclear. Here, we analyzed adult hippocampal neurogenesis in AD11 transgenic mice, in which the constitutive expression of anti-NGF antibody leads to an imbalance of proNGF over mature NGF. We found increased proliferation of progenitors but a reduced neurogenesis in the AD11 dentate gyrus (DG)-hippocampus (HP). Also in vitro, AD11 hippocampal neural stem cells (NSCs) proliferated more, but were unable to differentiate into morphologically mature neurons. By treating wild-type hippocampal progenitors with the uncleavable form of proNGF (proNGF-KR), we demonstrated that proNGF acts as mitogen on aNSCs at low concentration. The mitogenic effect of proNGF was specifically addressed to the radial glia-like (RGL) stem cells through the induction of cyclin D1 expression. These cells express high levels of p75NTR, as demonstrated by immunofluorescence analyses performed ex vivo on RGL cells isolated from freshly dissociated HP-DG or selected in vitro from NSCs by leukemia inhibitory factor. Clonogenic assay performed in the absence of mitogens showed that RGLs respond to proNGF-KR by reactivating their proliferation and thus leading to neurospheres formation. The mitogenic effect of proNGF was further exploited in the expansion of mouse-induced neural stem cells (iNSCs). Chronic exposure of iNSCs to proNGF-KR increased their proliferation. Altogether, we demonstrated that proNGF acts as mitogen on hippocampal and iNSCs. Stem Cells 2019;37:1223–1237

Primer development for detection of Phaseolus vulgaris and Olathe transgenic bean.

Several strategies have been employed for genetically engineering resistance to viruses in transgenic plants. The bean golden mosaic virus (BGMV) is responsible for causing the gold mosaic of common bean (Phaseolus vulgaris L.) and causes severe yield losses due to yellow-green mosaic of leaves, stunted growth and distorted pods. Olathe transgenic bean (Olathe 5.1) was successfully produced by EMBRAPA using the RNA interference (RNAi) concept to silence the rep viral gene in common bean to generate transgenic lines with strong resistance to BGMV. In this work, real time PCR (RT-PCR) method with SYBR Green was developed to detect this newly genetically modified (GM) plant

New plasmid calibrators for geminivirus-resistant (EMB-PV051-1 event) common bean (Phaseolus vulgaris L.) quantitation using simplex and duplex qPCR.

The geminivirus-resistant common bean, Embrapa 5.1, was the first commercial genetically modified (GM) event developed in Latin America by the Brazilian Agricultural Research Corp.. Therein novel standard reference plasmids were constructed for species-specific (pLEC) and event-specific (pFGM) qualitative and quantitative detection of Embrapa 5.1 GM common bean. To establish these plasmids as certified reference materials (CRM) for Embrapa 5.1 GM common bean, two DNA extraction protocols, simplex and duplex qPCR using two different operators (experimenters) were tested. The efficiency values ranged from 92% to 110% for the simplex and duplex reactions considering both operators. The limit of detection was enough to detect at least 0.1% GM content. These plasmids are suitable to be used as CRM for Embrapa 5.1 GM common bean. They will be useful for survey of food labels for compliance with legislation about GMO content in Brazil and in other countries where GM common bean is not yet approved for commercialization

TIMP3 interplays with apelin to regulate cardiovascular metabolism in hypercholesterolemic mice

Tissue inhibitor of metalloproteinase 3 (TIMP3) is an extracellular matrix (ECM) bound protein, which has been shown to be downregulated in human subjects and experimental models with cardiometabolic disorders, including type 2 diabetes mellitus, hypertension and atherosclerosis. The aim of this study was to investigate the effects of TIMP3 on cardiac energy homeostasis during increased metabolic stress conditions

Construção de plasmídeos calibrantes para quantificação do feijão Embrapa 5.1 por PCR em tempo real.

O objetivo deste trabalho foi a construção de um plasmídeo calibrante para quantificação do feijão Embrapa 5.1

Waiting times for diagnosis of attention-deficit hyperactivity disorder in children and adolescents referred to Italian ADHD centers must be reduced

BACKGROUND: To investigate timely access to and the time needed to complete the diagnostic path of children and adolescents with suspected attention deficit hyperactivity disorder (ADHD) in the 18 Italian Lombardy Region ADHD reference centers. METHODS: Data of children and adolescents enrolled in the Regional ADHD disease-oriented Registry for suspected ADHD who requested their first visit in 2013-2017 were analyzed. RESULTS: The sample comprised 2262 children and adolescents aged 5-17\u2009years who accessed the ADHD centers for diagnostic classification and management. The median waiting time was of 177\u2009days (range 66-375) from the request for the initial appointment to the completion of the diagnostic path, with a three - fold difference between centers. In addition to the center, the strongest significant predictors of long waiting times were age comorbidities, the severity of the disorder, and having already completed some diagnostic procedures provided by the common standard path. CONCLUSIONS: To guarantee an equal standard of care in ADHD centers for all children and adolescents there is a pressing need to reduce the times to complete the diagnostic path. It is the task of both policymakers and each center to optimize the quality of the service and of the care delivered

Extended Kalman Filter for Estimation of Parameters in Nonlinear State-Space Models of Biochemical Networks

It is system dynamics that determines the function of cells, tissues and organisms. To develop mathematical models and estimate their parameters are an essential issue for studying dynamic behaviors of biological systems which include metabolic networks, genetic regulatory networks and signal transduction pathways, under perturbation of external stimuli. In general, biological dynamic systems are partially observed. Therefore, a natural way to model dynamic biological systems is to employ nonlinear state-space equations. Although statistical methods for parameter estimation of linear models in biological dynamic systems have been developed intensively in the recent years, the estimation of both states and parameters of nonlinear dynamic systems remains a challenging task. In this report, we apply extended Kalman Filter (EKF) to the estimation of both states and parameters of nonlinear state-space models. To evaluate the performance of the EKF for parameter estimation, we apply the EKF to a simulation dataset and two real datasets: JAK-STAT signal transduction pathway and Ras/Raf/MEK/ERK signaling transduction pathways datasets. The preliminary results show that EKF can accurately estimate the parameters and predict states in nonlinear state-space equations for modeling dynamic biochemical networks

The Signaling Petri Net-Based Simulator: A Non-Parametric Strategy for Characterizing the Dynamics of Cell-Specific Signaling Networks

Reconstructing cellular signaling networks and understanding how they work are major endeavors in cell biology. The scale and complexity of these networks, however, render their analysis using experimental biology approaches alone very challenging. As a result, computational methods have been developed and combined with experimental biology approaches, producing powerful tools for the analysis of these networks. These computational methods mostly fall on either end of a spectrum of model parameterization. On one end is a class of structural network analysis methods; these typically use the network connectivity alone to generate hypotheses about global properties. On the other end is a class of dynamic network analysis methods; these use, in addition to the connectivity, kinetic parameters of the biochemical reactions to predict the network's dynamic behavior. These predictions provide detailed insights into the properties that determine aspects of the network's structure and behavior. However, the difficulty of obtaining numerical values of kinetic parameters is widely recognized to limit the applicability of this latter class of methods