228 research outputs found

    Purkinje cell input to cerebellar nuclei in tottering: Ultrastructure and physiology

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    Homozygous tottering mice are spontaneous ataxic mutants, which carry a mutation in the gene encoding the ion pore of the P/Q-type voltage-gated calcium channels. P/Q-type calcium channels are prominently expressed in Purkinje cell terminals, but it is unknown to what extent these inhibitory terminals in tottering mice are affected at the morphological and electrophysiological level. Here, we investigated the distribution and ultrastructure of their Purkinje cell terminals in the cerebellar nuclei as well as the activities of their target neurons. The densities of Purkinje cell terminals and their synapses were not significantly affected in the mutants. However, the Purkinje cell terminals were enlarged and had an increased number of vacuoles, whorled bodies, and mitochondria. These differences started to occur between 3 and 5 weeks of age and persisted throughout adulthood. Stimulation of Purkinje cells in adult tottering mice resulted in inhibition at normal latencies, but the activities of their postsynaptic neurons in the cerebellar nuclei were abnormal in that the frequency and irregularity of their spiking patterns were enhanced. Thus, although the number of their terminals and their synaptic contacts appear quantitatively intact, Purkinje cells in tottering mice show several signs of axonal damage that may contribute to altered postsynaptic activities in the cerebellar nuclei

    Genetic variants in novel pathways influence blood pressure and cardiovascular disease risk.

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    Blood pressure is a heritable trait influenced by several biological pathways and responsive to environmental stimuli. Over one billion people worldwide have hypertension (≥140 mm Hg systolic blood pressure or  ≥90 mm Hg diastolic blood pressure). Even small increments in blood pressure are associated with an increased risk of cardiovascular events. This genome-wide association study of systolic and diastolic blood pressure, which used a multi-stage design in 200,000 individuals of European descent, identified sixteen novel loci: six of these loci contain genes previously known or suspected to regulate blood pressure (GUCY1A3-GUCY1B3, NPR3-C5orf23, ADM, FURIN-FES, GOSR2, GNAS-EDN3); the other ten provide new clues to blood pressure physiology. A genetic risk score based on 29 genome-wide significant variants was associated with hypertension, left ventricular wall thickness, stroke and coronary artery disease, but not kidney disease or kidney function. We also observed associations with blood pressure in East Asian, South Asian and African ancestry individuals. Our findings provide new insights into the genetics and biology of blood pressure, and suggest potential novel therapeutic pathways for cardiovascular disease prevention

    Cadmium Induces p53-Dependent Apoptosis in Human Prostate Epithelial Cells

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    Cadmium, a widespread toxic pollutant of occupational and environmental concern, is a known human carcinogen. The prostate is a potential target for cadmium carcinogenesis, although the underlying mechanisms are still unclear. Furthermore, cadmium may induce cell death by apoptosis in various cell types, and it has been hypothesized that a key factor in cadmium-induced malignant transformation is acquisition of apoptotic resistance. We investigated the in vitro effects produced by cadmium exposure in normal or tumor cells derived from human prostate epithelium, including RWPE-1 and its cadmium-transformed derivative CTPE, the primary adenocarcinoma 22Rv1 and CWR-R1 cells and LNCaP, PC-3 and DU145 metastatic cancer cell lines. Cells were treated for 24 hours with different concentrations of CdCl2 and apoptosis, cell cycle distribution and expression of tumor suppressor proteins were analyzed. Subsequently, cellular response to cadmium was evaluated after siRNA-mediated p53 silencing in wild type p53-expressing RWPE-1 and LNCaP cells, and after adenoviral p53 overexpression in p53-deficient DU145 and PC-3 cell lines. The cell lines exhibited different sensitivity to cadmium, and 24-hour exposure to different CdCl2 concentrations induced dose- and cell type-dependent apoptotic response and inhibition of cell proliferation that correlated with accumulation of functional p53 and overexpression of p21 in wild type p53-expressing cell lines. On the other hand, p53 silencing was able to suppress cadmium-induced apoptosis. Our results demonstrate that cadmium can induce p53-dependent apoptosis in human prostate epithelial cells and suggest p53 mutation as a possible contributing factor for the acquisition of apoptotic resistance in cadmium prostatic carcinogenesis

    CONSORT-DEFINE explanation and elaboration: recommendations for enhancing reporting quality and impact of early phase dose-finding clinical trials

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    \ua9 2024 The Author(s). Early phase dose-finding (EPDF) trials are key in the development of novel therapies, with their findings directly informing subsequent clinical development phases and providing valuable insights for reverse translation. Comprehensive and transparent reporting of these studies is critical for their accurate and critical interpretation, which may improve and expedite therapeutic development. However, quality of reporting of design characteristics and results from EPDF trials is often variable and incomplete. The international consensus-based CONSORT-DEFINE (Consolidated Standards for Reporting Trials Dose-finding Extension) statement, an extension of the CONSORT statement for randomised trials, was developed to improve the reporting of EPDF trials. The CONSORT-DEFINE statement introduced 21 new items and modified 19 existing CONSORT items. This CONSORT-DEFINE Explanation and Elaboration (E&E) document provides important information to enhance understanding and facilitate the implementation of the CONSORT-DEFINE checklist. For each new or modified checklist item, we provide a detailed description and its rationale with supporting evidence, and present examples from EPDF trial reports published in peer-reviewed scientific journals. When reporting the results of EPDF trials, authors are encouraged to consult the CONSORT-DEFINE E&E document, together with the CONSORT and CONSORT-DEFINE statement papers, and adhere to their recommendations. Widespread adoption of the CONSORT-DEFINE statement is likely to enhance the reporting quality of EPDF trials, thus facilitating the peer review of such studies and their appraisal by researchers, regulators, ethics committee members, and funders. Funding: This work is a further extension of the CONSORT-DEFINE study, which was funded by the UK Medical Research Council (MRC)- National Institute for Health and Care Research (NIHR) Methodology Research Programme (MR/T044934/1). The Clinical Trials and Statistics Unit at The Institute of Cancer Research (ICR-CTSU) receives programmatic infrastructure funding from Cancer Research UK (C1491/A25351; CTUQQR-Dec 22/100 004), which has contributed to accelerating the advancement and successful completion of this work

    SPIRIT-DEFINE explanation and elaboration: recommendations for enhancing quality and impact of early phase dose-finding clinical trials protocols

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    \ua9 2024 The Author(s). Transparent and accurate reporting in early phase dose-finding (EPDF) clinical trials is crucial for informing subsequent larger trials. The SPIRIT statement, designed for trial protocol content, does not adequately cover the distinctive features of EPDF trials. Recent findings indicate that the protocol contents in past EPDF trials frequently lacked completeness and clarity. To address this gap, the international consensus-driven SPIRIT-DEFINE checklist was developed through a robust methodological framework for guideline development, with the aim to improve completeness and clarity in EPDF trial protocols. The checklist builds on the SPIRIT statement, adding 17 new items and modifying 15 existing ones. The SPIRIT-DEFINE explanation and elaboration (E&E) document provides comprehensive information to enhance understanding and usability of the SPIRIT-DEFINE checklist when writing an EPDF trial protocol. Each new or modified checklist item is accompanied by a detailed description, its rationale with supportive evidence, and examples of good reporting curated from EPDF trial protocols covering a range of therapeutic areas and interventions. We recommend utilising this paper alongside the SPIRIT statement, and any relevant extensions, to enhance the development and review of EPDF trial protocols. By facilitating adoption of the SPIRIT-DEFINE statement for EPDF trials, this E&E document can promote enhancement of methodological rigour, patient safety, transparency, and facilitate the generation of high-quality, reproducible evidence that will strengthen the foundation of early phase research and ultimately improve patient outcomes. Funding: This work is a further extension of the SPIRIT-DEFINE study, which obtained no external funding. The principal investigator (CY) used internal staff resources, together with additional resources from external partners, to conduct this study. The SPIRIT-DEFINE study is a component of the DEFINE project, which also developed the MRC/ NIHR funded CONSORT-DEFINE guidance. ICR-CTSU receives programmatic infrastructure funding from Cancer Research UK (C1491/A25351; CTUQQR-Dec22/100004), which has contributed to accelerating the advancement and successful completion of this work

    Physical activity referrals in Swedish primary health care – prescriber and patient characteristics, reasons for prescriptions, and prescribed activities

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    <p>Abstract</p> <p>Background</p> <p>Over the past decade, practitioners in primary health care (PHC) settings in many countries have issued written prescriptions to patients to promote increased physical activity or exercise. The aim of this study is to describe and analyse a comprehensive physical activity referral (PAR) scheme implemented in a routine PHC setting in Östergötland County. The study examines characteristics of the PARs recipients and referral practitioners, identifies reasons why practitioners opted to use PARs with their clients, and discusses prescribed activities and prescriptions in relation to PHC registries.</p> <p>Methods</p> <p>Prospective prescription data were obtained for 90% of the primary health care centres in Östergötland County, Sweden, in 2004 and 2005. The study population consisted of patients who were issued PARs after they were deemed likely to benefit from increased physical activity, as assessed by PHC staff.</p> <p>Results</p> <p>During the two-year period, a total of 6,300 patients received PARs. Two-thirds of the patients were female and half of the patients were 45–64 years. Half of the patients (50.8%) who received PARs were recommended a home-based activity, such as walking. One third (33%) of the patients issued PARs were totally inactive, reporting no days of physical activity that lasted for 30 minutes, and 29% stated that they reached this level 1–2 days per week.</p> <p>The number of PARs prescribed per year in relation to the number of unique individuals that visited primary health care during one year was 1.4% in 2004 and 1.2% in 2005. Two-thirds of the combined prescriptions were issued by physicians (38%) and nurses (31%). Physiotherapists and behavioural scientists issued the highest relative number of prescriptions. The most common reasons for issuing PARs were musculoskeletal disorders (39.1%) and overweight (35.4%), followed by high blood pressure (23.3%) and diabetes (23.2%).</p> <p>Conclusion</p> <p>Östergötland County's PAR scheme reached a relatively high proportion of physically inactive people visiting local PHC centres for other health reasons. PAR-related statistics, including PAR-rates by individual PHC centres and PAR- rates per health professional category, show differences in prescribing activities, both by patient categories, and by prescribing professionals.</p
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