488 research outputs found

    Very small deletions within the NESP55 gene in pseudohypoparathyroidism type 1b

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    Pseudohypoparathyroidism (PHP) is caused by reduced expression of genes within the GNAS cluster, resulting in parathormone resistance. The cluster contains multiple imprinted transcripts, including the stimulatory G protein Ī± subunit (Gs-Ī±) and NESP55 transcript preferentially expressed from the maternal allele, and the paternally expressed XLas, A/B and antisense transcripts. PHP1b can be caused by loss of imprinting affecting GNAS A/B alone (associated with STX16 deletion), or the entire GNAS cluster (associated with deletions of NESP55 in a minority of cases). We performed targeted genomic next-generation sequencing (NGS) of the GNAS cluster to seek variants and indels underlying PHP1b. Seven patients were sequenced by hybridisation-based capture and fourteen more by long-range PCR and transposon-mediated insertion and sequencing. A bioinformatic pipeline was developed for variant and indel detection. In one family with two affected siblings, and in a second family with a single affected individual, we detected maternally inherited deletions of 40 and 33 bp, respectively, within the deletion previously reported in rare families with PHP1b. All three affected individuals presented with atypically severe PHP1b; interestingly, the unaffected mother in one family had the detected deletion on her maternally inherited allele. Targeted NGS can reveal sequence changes undetectable by current diagnostic methods. Identification of genetic mutations underlying epigenetic changes can facilitate accurate diagnosis and counselling, and potentially highlight genetic elements critical for normal imprint settin

    Mapping of ESE-1 subdomains required to initiate mammary epithelial cell transformation via a cytoplasmic mechanism

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    <p>Abstract</p> <p>Background</p> <p>The ETS family transcription factor ESE-1 is often overexpressed in human breast cancer. ESE-1 initiates transformation of MCF-12A cells via a non-transcriptional, cytoplasmic process that is mediated by a unique 40-amino acid serine and aspartic acid rich (SAR) subdomain, whereas, ESE-1's nuclear transcriptional property is required to maintain the transformed phenotype of MCF7, ZR-75-1 and T47D breast cancer cells.</p> <p>Results</p> <p>To map the minimal functional nuclear localization (NLS) and nuclear export (NES) signals, we fused in-frame putative NLS and NES motifs between GFP and the SAR domain. Using these GFP constructs as reporters of subcellular localization, we mapped a single NLS to six basic amino acids (<sup>242</sup>HGKRRR<sup>247</sup>) in the AT-hook and two CRM1-dependent NES motifs, one to the pointed domain (NES1: <sup>102</sup>LCNCALEELRL<sup>112</sup>) and another to the DNA binding domain (DBD), (NES2: <sup>275</sup>LWEFIRDILI<sup>284</sup>). Moreover, analysis of a putative NLS located in the DBD (<sup>316</sup>GQKKKNSN<sup>323</sup>) by a similar GFP-SAR reporter or by internal deletion of the DBD, revealed this sequence to lack NLS activity. To assess the role of NES2 in regulating ESE-1 subcellular localization and subsequent transformation potency, we site-specifically mutagenized NES2, within full-length GFP-ESE-1 and GFP-NES2-SAR reporter constructs. These studies show that site-specific mutation of NES2 completely abrogates ESE-1 transforming activity. Furthermore, we show that exclusive cytoplasmic targeting of the SAR domain is sufficient to initiate transformation, and we report that an intact SAR domain is required, since block mutagenesis reveals that an intact SAR domain is necessary to maintain its full transforming potency. Finally, using a monoclonal antibody targeting the SAR domain, we demonstrate that the SAR domain contains a region accessible for protein - protein interactions.</p> <p>Conclusions</p> <p>These data highlight that ESE-1 contains NLS and NES signals that play a critical role in regulating its subcellular localization and function, and that an intact SAR domain mediates MEC transformation exclusively in the cytoplasm, via a novel nontranscriptional mechanism, whereby the SAR motif is accessible for ligand and/or protein interactions. These findings are significant, since they provide novel molecular insights into the functions of ETS transcription factors in mammary cell transformation.</p

    Desperately Seeking Dissonance: Identifying the Disconfirming Case in Qualitative Evidence Synthesis

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    Actively seeking the disconfirming or deviant case is properly regarded as a hallmark of trustworthiness in primary qualitative research. The need to subject emergent theory to such testing is no less important within qualitative systematic reviews. There is, as yet, little available guidance on how to implement such strategies. Few researchers have described the practicalities of seeking the disconfirming case. We survey the methodological literature to gain a better understanding of how systematic reviews of qualitative research handle the disconfirming case. We reflect on our own experience from three recent qualitative evidence syntheses. We describe how reviewers might actively manufacture opportunities to identify discrepant or refutational findings. We conclude by outlining possible methods by which a team might integrate active seeking of a disconfirming case within the overall review process

    Elevated levels of inflammatory cytokines predict survival in idiopathic and familial pulmonary arterial hypertension

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    BACKGROUND: Inflammation is a feature of pulmonary arterial hypertension (PAH), and increased circulating levels of cytokines are reported in patients with PAH. However, to date, no information exists on the significance of elevated cytokines or their potential as biomarkers. We sought to determine the levels of a range of cytokines in PAH and to examine their impact on survival and relationship to hemodynamic indexes. METHODS AND RESULTS: We measured levels of serum cytokines (tumor necrosis factor-alpha, interferon-gamma and interleukin-1beta, -2, -4, -5, -6, -8, -10, -12p70, and -13) using ELISAs in idiopathic and heritable PAH patients (n=60). Concurrent clinical data included hemodynamics, 6-minute walk distance, and survival time from sampling to death or transplantation. Healthy volunteers served as control subjects (n=21). PAH patients had significantly higher levels of interleukin-1beta, -2, -4, -6, -8, -10, and -12p70 and tumor necrosis factor-alpha compared with healthy control subjects. Kaplan-Meier analysis showed that levels of interleukin-6, 8, 10, and 12p70 predicted survival in patients. For example, 5-year survival with interleukin-6 levels of >9 pg/mL was 30% compared with 63% for patients with levels < or = 9 pg/mL (P=0.008). In this PAH cohort, cytokine levels were superior to traditional markers of prognosis such as 6-minute walk distance and hemodynamics. CONCLUSIONS: This study illustrates dysregulation of a broad range of inflammatory mediators in idiopathic and familial PAH and demonstrates that cytokine levels have a previously unrecognized impact on patient survival. They may prove to be useful biomarkers and provide insight into the contribution of inflammation in PAH

    Intrinsically chiral ferronematic liquid crystals : An inversion of the helical twist sense at the chiral nematic ā€“ Chiral ferronematic phase transition

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    Funding Information: The research was supported by the National Science Centre (Poland) under the grant no. 2016/22/A/ST5/00319. C.T.I. and J.M.D.S. acknowledge the financial support of the Engineering and Physical Sciences Research Council [EP/V048775/1].Peer reviewedPostprin

    Abnormal structural and functional brain connectivity in gray matter heterotopia

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    available in PMC 2013 June 01Purpose:ā€‚ Periventricular nodular heterotopia (PNH) is a malformation of cortical development associated with epilepsy and dyslexia. Evidence suggests that heterotopic gray matter can be functional in brain malformations and that connectivity abnormalities may be important in these disorders. We hypothesized that nodular heterotopia develop abnormal connections and systematically investigated the structural and functional connectivity of heterotopia in patients with PNH. Methods:ā€‚ Eleven patients were studied using diffusion tensor tractography and resting-state functional connectivity MRI with bold oxygenation levelā€“dependent (BOLD) imaging. Fiber tracks with a terminus within heterotopic nodules were visualized to determine structural connectivity, and brain regions demonstrating resting-state functional correlations to heterotopic nodules were analyzed. Relationships between these connectivity results and measures of clinical epilepsy and cognitive disability were examined. Key Findings:ā€‚ A majority of heterotopia (69%) showed structural connectivity to discrete regions of overlying cortex, and almost all (96%) showed functional connectivity to these regions (mean peak correlation coefficient 0.61). Heterotopia also demonstrated connectivity to regions of contralateral cortex, other heterotopic nodules, ipsilateral but nonoverlying cortex, and deep gray matter structures or the cerebellum. Patients with the longest durations of epilepsy had a higher degree of abnormal functional connectivity (p = 0.036). Significance:ā€‚ Most heterotopic nodules in PNH are structurally and functionally connected to overlying cortex, and the strength of abnormal connectivity is higher among patients with the longest duration of epilepsy. Along with prior evidence that cortico-cortical tract defects underlie dyslexia in this disorder, the current findings suggest that altered connectivity is likely a critical substrate for neurologic dysfunction in brain malformations.National Institutes of Health (U.S.) (NIH/NINDS R01 NS073601)National Institutes of Health (U.S.) (NIH/NINDS K23 NS049159)Epilepsy Foundation of AmericaHarvard University (William F. Milton Fund

    Thymic output and CD4 T-cell reconstitution in HIV-infected children on early and interrupted antiretroviral treatment: evidence from the CHER trial.

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    Objectives: Early treatment of HIV-infected children and adults is important for optimal immune reconstitution. Infantsā€™ immune systems are more plastic and dynamic than older childrenā€™s or adultsā€™, and deserve particular attention. This study aimed to understand the response of the HIV-infected infant immune system to early antiretroviral therapy (ART) and planned ART interruption and re-start. Design: We used linear and nonlinear regression and mixed-effects models to describe childrenā€™s CD4 trajectories and to identify predictors of CD4 count during early and interrupted ART. Methods: Data from HIV-infected children enrolled CHER trial, starting ART aged between 6 and 12 weeks, was used to explore the effect of ART on immune reconstitution. Results: Early treatment arrested the decline in CD4 count but did not fully restore it to the levels observed in HIV-uninfected children. Treatment interruption at 40 or 96 weeks resulted in a rapid decline in CD4 T-cells, which on retreatment returned to levels observed before interruption. NaĆÆve CD4 T-cell count was an important determinant of overall CD4 levels. A strong correlation was observed between thymic output and the stable CD4 count both before and after treatment interruption. Conclusions: Early identification and treatment of HIV-infected infants is important to stabilize CD4 counts at the highest levels possible. Once stabilized, childrenā€™s CD4 counts appear resilient, with good potential for recovery following treatment interruption. The naĆÆve T-cell pool and thymic production of naive cells are key determinants of childrenā€™s CD4 levels

    Olfactory signals and fertility in olive baboons.

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    Female primates signal impending ovulation with a suite of sexual signals. Studies of these signals have focussed on visual, and to a lesser extent, acoustic signals, neglecting olfactory signals. We aimed to investigate the information content of female olfactory signals in captive olive baboons (Papio anubis) and relate these to the female fertile period. We studied eight adult females living in four groups at the CNRS Station de Primatologie, Rousset-sur-Arc, France. We used vaginal cytology to detect ovulation. We investigated the volatile component of odour signals using solid-phase microextraction and gas chromatography-mass spectrometry.Ā We found a total of 74 volatile compounds, of which we tentatively identified 25, including several ketones, alcohols, aldehydes, terpenes, volatile fatty acids and hydrocarbons that have been identified in odour profiles of other primates. Our results show that vaginal odour intensity differs with sexual cycle stage suggesting that odour might play a role in signalling female baboon fertility. We found differences in vaginal odour between females living in all-female and in mixed sex groups but we could not distinguish the effects of group composition, female age and identity. This study of olfactory signalling improves our understanding of how female primates advertise their sexual receptivity

    Differential adaptation of Candida albicans in vivo modulates immune recognition by dectin-1

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    Author Summary Dectin-1 is a pattern recognition receptor recognising the fungal cell-wall component, Ī²-glucan, and plays an essential role in controlling C. albicans infections in both mouse and man. Candida albicans is part of the normal human microflora, yet is capable of causing superficial mucosal infections as well as life-threatening invasive diseases, particularly in patients whose immune function is compromised. Here we found that the contribution of Dectin-1 is limited to specific strains of C. albicans ; effects which are due to the differential adaptation of these pathogens during infection. Importantly, C. albicans strains showed variations in both the composition and nature of their cell walls, and it was these differences which influenced the role of Dectin-1. Crucially, we found that we could alter the fungal cell wall, and subsequent interactions with the host, using antifungal drugs. These findings have substantial implications for our understanding of the factors contributing to human susceptibility to infections with C. albicans , but also treatment strategies
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