156 research outputs found

    Ī±<sub>1L</sub>-adrenoceptors mediate contraction of human erectile tissue

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    Ī±1-adrenoceptor antagonists can impact upon sexual function and have potential in the treatment of erectile dysfunction. Human erectile tissue contains predominantly Ī±1A-adrenoceptors, and here we examined whether contractions of this tissue are mediated by the functional phenotype, the Ī±1L-adrenoceptor. Functional experiments using subtype selective agonists and antagonists, along with radioligand ([3H]tamsulosin) binding assays, were used to determine the Ī±1-adrenoceptor population. A61603, a Ī±1A-adrenoceptor agonist, was a full agonist with a potency 21-fold greater than that of noradrenaline. The Ī±1A- and Ī±1D-adrenoceptor antagonist tamsulosin antagonized noradrenaline responses with high affinity (pKDĀ =Ā 9.7Ā Ā±Ā 0.3), whilst BMY7378 (100Ā nM) (Ī±1D-adrenoceptor antagonist) failed to antagonize responses. In contrast, relatively low affinity estimates were obtained for both prazosin (pKDĀ =Ā 8.2Ā Ā±Ā 0.1) and RS17053 (pKDĀ =Ā 6.9Ā Ā±Ā 0.2), antagonists which discriminate between the Ī±1A- and Ī±1L-adrenoceptors. [3H]Tamsulosin bound with high affinity to the receptors of human erectile tissue (pKDĀ =Ā 10.3Ā Ā±Ā 0.1) with a receptor density of 28.1Ā Ā±Ā 1.4Ā fmolĀ mgāˆ’1 protein. Prazosin displacement of [3H]tamsulosin binding revealed a single homogenous population of binding sites with a relatively low affinity for prazosin (pKiĀ =Ā 8.9). Taken together these data confirm that the receptor mediating contraction in human erectile tissue has the pharmacological properties of the Ī±1L-adrenoceptor. Keywords: Erectile tissue, Ī±1-adrenoceptor subtypes, Ī±1L-adrenoceptor, Tamsulosin, Prazosi

    Human neutrophil clearance of bacterial pathogens triggers anti-microbial gamma delta T cell responses in early infection

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    Human blood Vc9/Vd2 T cells, monocytes and neutrophils share a responsiveness toward inflammatory chemokines and are rapidly recruited to sites of infection. Studying their interaction in vitro and relating these findings to in vivo observations in patients may therefore provide crucial insight into inflammatory events. Our present data demonstrate that Vc9/Vd2 T cells provide potent survival signals resulting in neutrophil activation and the release of the neutrophil chemoattractant CXCL8 (IL-8). In turn, Vc9/Vd2 T cells readily respond to neutrophils harboring phagocytosed bacteria, as evidenced by expression of CD69, interferon (IFN)-c and tumor necrosis factor (TNF)-a. This response is dependent on the ability of these bacteria to produce the microbial metabolite (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP), requires cell-cell contact of Vc9/Vd2 T cells with accessory monocytes through lymphocyte function-associated antigen-1 (LFA-1), and results in a TNF-a dependent proliferation of Vc9/Vd2 T cells. The antibiotic fosmidomycin, which targets the HMB-PP biosynthesis pathway, not only has a direct antibacterial effect on most HMB-PP producing bacteria but also possesses rapid anti-inflammatory properties by inhibiting cd T cell responses in vitro. Patients with acute peritoneal-dialysis (PD)-associated bacterial peritonitis ā€“ characterized by an excessive influx of neutrophils and monocytes into the peritoneal cavity ā€“ show a selective activation of local Vc9/Vd2 T cells by HMB-PP producing but not by HMB-PP deficient bacterial pathogens. The cd T celldriven perpetuation of inflammatory responses during acute peritonitis is associated with elevated peritoneal levels of cd T cells and TNF-a and detrimental clinical outcomes in infections caused by HMB-PP positive microorganisms. Taken together, our findings indicate a direct link between invading pathogens, neutrophils, monocytes and microbe-responsive cd T cells in early infection and suggest novel diagnostic and therapeutic approaches.Martin S. Davey, Chan-Yu Lin, Gareth W. Roberts, SinĆ©ad Heuston, Amanda C. Brown, James A. Chess, Mark A. Toleman, Cormac G.M. Gahan, Colin Hill, Tanya Parish, John D. Williams, Simon J. Davies, David W. Johnson, Nicholas Topley, Bernhard Moser and Matthias Eber

    Negative emotions set in motion : the continued relevance of #GamerGate

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    This chapter aims at making sense of the #GamerGate (#GG) online harassment campaign that was particularly active in 2014ā€“2015 but to this day continues to produce hateful speech against certain ideologies and minorities in gaming culture. The campaign was especially successful at building online visibility through harassment, and the affective resonances of the issues it raised have since translated into general online campaigning how-toā€™s, financial earnings, and even political action outside of the gaming sphere. Although the primary breeding ground for this movement was 4chan (and later, 8chan), it only reached public awareness and visibility ā€“ hence, effectiveness ā€“ through Twitter and, to a lesser extent, through YouTube. In order to understand the emotional charge and political relevance of this campaign, we rely on both quantitative and qualitative activity analyses of the Twitter users that use the hashtag #GamerGate between 2014 and 2019. In addition to analyzing who were the most active tweeters and what kind of resonance their tweets elicited, we looked into the emotional qualities of their communication. The communication strategies of #GG tweeters took advantage of the language and cultural references of the target demographic to drive a set of topics into public discourse and, further, to political activism. This discourse utilized a combination of affective modes, based mainly on resentment and schadenfreude, that we see echoing in many places on the internet. In the end, we argue that while #GG may have been only one instance of a campaign with harassment elements, the sentiments it cultivated and amplified as well as its operational logics have since been successfully employed in many similar online movements, including the current political campaigning associated with the so-called alt-right.fi=vertaisarvioitu|en=peerReviewed

    Replication profile of PCDH11X and PCDH11Y, a gene pair located in the non-pseudoautosomal homologous region Xq21.3/Yp11.2

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    In order to investigate the replication timing properties of PCDH11X and PCDH11Y, a pair of protocadherin genes located in the hominid-specific non-pseudoautosomal homologous region Xq21.3/Yp11.2, we conducted a FISH-based comparative study in different human and non-human primate (Gorilla gorilla) cell types. The replication profiles of three genes from different regions of chromosome X (ZFX, XIST and ATRX) were used as terms of reference. Particular emphasis was given to the evaluation of allelic replication asynchrony in relation to the inactivation status of each gene. The human cell types analysed include neuronal cells and ICF syndrome cells, considered to be a model system for the study of X inactivation. PCDH11 appeared to be generally characterized by replication asynchrony in both male and female cells, and no significant differences were observed between human and gorilla, in which this gene lacks X-Y homologous status. However, in differentiated human neuroblastoma and cerebral cortical cells PCDH11X replication profile showed a significant shift towards allelic synchrony. Our data are relevant to the complex relationship between X-inactivation, as a chromosome-wide phenomenon, and asynchrony of replication and expression status of single genes on chromosome X

    Dual DNA Methylation Patterns in the CNS Reveal Developmentally Poised Chromatin and Monoallelic Expression of Critical Genes

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    As a first step towards discovery of genes expressed from only one allele in the CNS, we used a tiling array assay for DNA sequences that are both methylated and unmethylated (the MAUD assay). We analyzed regulatory regions of the entire mouse brain transcriptome, and found that approximately 10% of the genes assayed showed dual DNA methylation patterns. They include a large subset of genes that display marks of both active and silent, i.e., poised, chromatin during development, consistent with a link between differential DNA methylation and lineage-specific differentiation within the CNS. Sixty-five of the MAUD hits and 57 other genes whose function is of relevance to CNS development and/or disorders were tested for allele-specific expression in F1 hybrid clonal neural stem cell (NSC) lines. Eight MAUD hits and one additional gene showed such expression. They include Lgi1, which causes a subtype of inherited epilepsy that displays autosomal dominance with incomplete penetrance; Gfra2, a receptor for glial cell line-derived neurotrophic factor GDNF that has been linked to kindling epilepsy; Unc5a, a netrin-1 receptor important in neurodevelopment; and Cspg4, a membrane chondroitin sulfate proteoglycan associated with malignant melanoma and astrocytoma in human. Three of the genes, Camk2a, Kcnc4, and Unc5a, show preferential expression of the same allele in all clonal NSC lines tested. The other six genes show a stochastic pattern of monoallelic expression in some NSC lines and bi-allelic expression in others. These results support the estimate that 1ā€“2% of genes expressed in the CNS may be subject to allelic exclusion, and demonstrate that the group includes genes implicated in major disorders of the CNS as well as neurodevelopment

    Female gamersā€™ experience of online harassment and social support in online gaming: a qualitative study

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    Female gaming is a relatively under-researched area, and female gamers often report experiencing harassment whilst playing online. The present study explored female experiences of social support while playing online video games, because of the previous research suggesting that females often experience harassment and negative interactions during game play. Data were collected from an online discussion forum, and comprised posts drawn from 271 female gamers. Thematic analysis of the discussions suggested that a lack of social support and harassment frequently led to female gamers playing alone, playing anonymously, and moving groups regularly. The female gamers reported experiencing anxiety and loneliness due to this lack of social support, and for many, this was mirrored in their experiences of social support outside of gaming. The female gamers frequently accepted the incorporation into their gaming of specific coping strategies to mitigate online harassment, including actively hiding their identity and avoiding all forms of verbal communication with other players. These themes are discussed in relation to relevant research in the area, along with recommendations for future research and consideration of possible explanations for the themes observed

    Hearts from Mice Fed a Non-Obesogenic High-Fat Diet Exhibit Changes in Their Oxidative State, Calcium and Mitochondria in Parallel with Increased Susceptibility to Reperfusion Injury

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    High-fat diet with obesity-associated co-morbidities triggers cardiac remodeling and renders the heart more vulnerable to ischemia/reperfusion injury. However, the effect of high-fat diet without obesity and associated co-morbidities is presently unknown.To characterize a non-obese mouse model of high-fat diet, assess the vulnerability of hearts to reperfusion injury and to investigate cardiac cellular remodeling in relation to the mechanism(s) underlying reperfusion injury.Feeding C57BL/6J male mice high-fat diet for 20 weeks did not induce obesity, diabetes, cardiac hypertrophy, cardiac dysfunction, atherosclerosis or cardiac apoptosis. However, isolated perfused hearts from mice fed high-fat diet were more vulnerable to reperfusion injury than those from mice fed normal diet. In isolated cardiomyocytes, high-fat diet was associated with higher diastolic intracellular Ca2+ concentration and greater damage to isolated cardiomyocytes following simulated ischemia/reperfusion. High-fat diet was also associated with changes in mitochondrial morphology and expression of some related proteins but not mitochondrial respiration or reactive oxygen species turnover rates. Proteomics, western blot and high-performance liquid chromatography techniques revealed that high-fat diet led to less cardiac oxidative stress, higher catalase expression and significant changes in expression of putative components of the mitochondrial permeability transition pore (mPTP). Inhibition of the mPTP conferred relatively more cardio-protection in the high-fat fed mice compared to normal diet.This study shows for the first time that high-fat diet, independent of obesity-induced co-morbidities, triggers changes in cardiac oxidative state, calcium handling and mitochondria which are likely to be responsible for increased vulnerability to cardiac insults

    Schizophrenia-associated somatic copy-number variants from 12,834 cases reveal recurrent NRXN1 and ABCB11 disruptions

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    While germline copy-number variants (CNVs) contribute to schizophrenia (SCZ) risk, the contribution of somatic CNVs (sCNVs)ā€”present in some but not all cellsā€”remains unknown. We identified sCNVs using blood-derived genotype arrays from 12,834 SCZ cases and 11,648 controls, filtering sCNVs at loci recurrently mutated in clonal blood disorders. Likely early-developmental sCNVs were more common in cases (0.91%) than controls (0.51%, p = 2.68eāˆ’4), with recurrent somatic deletions of exons 1ā€“5 of the NRXN1 gene in five SCZ cases. Hi-C maps revealed ectopic, allele-specific loops forming between a potential cryptic promoter and non-coding cis-regulatory elements upon 5ā€² deletions in NRXN1. We also observed recurrent intragenic deletions of ABCB11, encoding a transporter implicated in anti-psychotic response, in five treatment-resistant SCZ cases and showed that ABCB11 is specifically enriched in neurons forming mesocortical and mesolimbic dopaminergic projections. Our results indicate potential roles of sCNVs in SCZ risk
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