Wnt signaling: multiple functions in neural development

Abstract.: Wnt signaling has proven to be essential for neural development at various stages and across species. Wnts are involved in morphogenesis and patterning, and their proliferation-promoting role is a key function in stem cell maintenance and the expansion of progenitor pools. Moreover, Wnt signaling is involved in differentiation processes and lineage decision events during both central and peripheral nervous system development. Additionally, several reports point to a role of Wnt signaling in axon guidance and neurite outgrowth. This article reviews and consolidates the existing evidence for the functions of Wnt signaling in neural developmen

A comparative analysis of tie2-positive IVD progenitor cells in single-cell and bulk transcriptomics.

Introduction: Back pain and disability are often attributed to intervertebral disc (IVD) degeneration1, where current treatments are limited by an incomplete understanding of IVD biology. This study focuses on the Angiopoietin-1 receptor Tie2, which marks a progenitor cell subset in the nucleus pulposus (NP)2, crucial for repair and regeneration3,4. We aim to elucidate the transcriptomic profile of these Tie2-positive NP progenitor cells (NPPCs) to understand their role in IVD homeostasis and repair. Methods: We utilized single-cell and bulk RNA sequencing to characterize the transcriptomic profiles of Tie2-positive NPPCs from bovine and human IVDs. For single-cell sequencing, reanalysis was conducted on the dataset published by Caliò et al. (2021)5, which included samples comprising pooled cells from three adjacent discs of either distal or proximal region of the bovine coccygeal tail of two biological replicates. Single-cell suspension was obtained through enzymatic dissociation using Collagenase Type II. Library preparation followed the single-cell 3’-version-3-protocol6 and sequencing was performed on the Illumina NovaSeq platform. The sequencing data were aligned to the Bos taurus reference genome (UMD-v3.1 Release-92) from Ensembl. Post-sequencing analysis involved cell cluster identification using the Seurat package. In parallel, bulk RNA sequencing was conducted on human IVD samples. Cells were isolated, and Tie2-positive cells were obtained by subsequent fluorescent activated cell sorting (FACS). These cells were subsequently expanded for one week. We compared Tie2-enriched samples from four healthy individuals, to Tie2-negative samples from three healthy individuals using the NovaSeq system. Differential expression analysis was carried out using DESeq2 to pinpoint marker genes specific to Tie2-enrichment. Furthermore, we performed Pearson correlation analysis contrasting the expression profiles of each identified single-cell cluster against the average profile of the Tie2-enriched samples, which facilitated the delineation of potential NPPC clusters. Results: We identified 14 distinct cell clusters (Fig. 1), underscoring NP cellular heterogeneity. Although not expressing a significant higher expression of the TEK gene, the gene for Tie2, Tie2-positive NPPCs exhibited a unique gene expression profile when compared to Tie2-negative cells, with specific marker genes identified. Through correlation analysis, these NPPCs were associated with specific clusters, suggesting a specialized “niche” in the IVD. Enrichment analysis indicated their involvement in tissue homeostasis and regeneration

Test beam results for an upgraded forward tagger of the L3 experiment at LEP II

We have tested new scintillator modules with silicon photodiode readout for the upgraded Active Lead Rings (ALR) of the L3 detector at LEP II. Results are presented from data recorded in muon and electron test beams with particular emphasis on the light production and collection as a function of the particle impact position on the scintillator modules. The results from the beam test data will be used for the design of the readout and trigger electronics in conjunction with the required ALR performance as an electron tagger and beam background monitor at LEP II

Effect of housing system on reproductive behaviour and on some endocrinological and seminal parameters of donkey stallions

Reproductive management of male donkeys employed for artificial breeding has been poorly studied. The aim of this study was to evaluate the effect of housing system, with the animals grouped together in a paddock or kept in individual boxes, on sexual behaviour, cortisol and testosterone concentration and seminal characteristics of adult male donkeys. The study included four Amiata donkey jacks (stallions) from which ejaculates, saliva and blood were collected during two distinct 3 weeks periods, one in the group and one in the box housing system. Time needed for semen collection was shorter when donkeys were kept in paddocks compared to when they were kept in single boxes (14:57 ± 07:27 and 20:52 ± 09:31 min, p < .05). Native semen characteristics were not influenced by housing system, while cooled preservation in an Equitainer(®) showed that sperm motility parameters were significantly higher during the paddock period compared to the box period. Salivary cortisol was influenced by housing system, both before and 60 min after ejaculation, being statistically higher when donkeys were housed in paddocks. On the contrary, overall and basal testosterone concentrations were significantly higher when animals were kept in boxes. In conclusion, in the present study, good quality semen could be successfully collected from donkeys irrespective of the housing system despite some differences in hormone concentrations

The Minimal Supersymmetric Standard Model: Group Summary Report

CONTENTS: 1. Synopsis, 2. The MSSM Spectrum, 3. The Physical Parameters, 4. Higgs Boson Production and Decays, 5. SUSY Particle Production and Decays, 6. Experimental Bounds on SUSY Particle Masses, 7. References.Comment: 121 pages, latex + epsfig, graphicx, axodraw, Report of the MSSM working group for the Workshop "GDR-Supersym\'etrie",France. Rep. PM/98-4

Radiation hardness qualification of PbWO4 scintillation crystals for the CMS Electromagnetic Calorimeter

This is the Pre-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2010 IOPEnsuring the radiation hardness of PbWO4 crystals was one of the main priorities during the construction of the electromagnetic calorimeter of the CMS experiment at CERN. The production on an industrial scale of radiation hard crystals and their certification over a period of several years represented a difficult challenge both for CMS and for the crystal suppliers. The present article reviews the related scientific and technological problems encountered

Intercalibration of the barrel electromagnetic calorimeter of the CMS experiment at start-up

Calibration of the relative response of the individual channels of the barrel electromagnetic calorimeter of the CMS detector was accomplished, before installation, with cosmic ray muons and test beams. One fourth of the calorimeter was exposed to a beam of high energy electrons and the relative calibration of the channels, the intercalibration, was found to be reproducible to a precision of about 0.3%. Additionally, data were collected with cosmic rays for the entire ECAL barrel during the commissioning phase. By comparing the intercalibration constants obtained with the electron beam data with those from the cosmic ray data, it is demonstrated that the latter provide an intercalibration precision of 1.5% over most of the barrel ECAL. The best intercalibration precision is expected to come from the analysis of events collected in situ during the LHC operation. Using data collected with both electrons and pion beams, several aspects of the intercalibration procedures based on electrons or neutral pions were investigated

Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE

Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV

A search for new physics is presented based on an event signature of at least three jets accompanied by large missing transverse momentum, using a data sample corresponding to an integrated luminosity of 36 inverse picobarns collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector at the LHC. No excess of events is observed above the expected standard model backgrounds, which are all estimated from the data. Exclusion limits are presented for the constrained minimal supersymmetric extension of the standard model. Cross section limits are also presented using simplified models with new particles decaying to an undetected particle and one or two jets