524 research outputs found

    The Stargazin-Related Protein {gamma}7 Interacts with the mRNA-Binding Protein Heterogeneous Nuclear Ribonucleoprotein A2 and Regulates the Stability of Specific mRNAs, Including CaV2.2

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    The role(s) of the novel stargazin-like {gamma}-subunit proteins remain controversial. We have shown previously that the neuron-specific {gamma}7 suppresses the expression of certain calcium channels, particularly CaV2.2, and is therefore unlikely to operate as a calcium channel subunit. We now show that the effect of {gamma}7 on CaV2.2 expression is via an increase in the degradation rate of CaV2.2 mRNA and hence a reduction of CaV2.2 protein level. Furthermore, exogenous expression of {gamma}7 in PC12 cells also decreased the endogenous CaV2.2 mRNA level. Conversely, knockdown of endogenous {gamma}7 with short-hairpin RNAs produced a reciprocal enhancement of CaV2.2 mRNA stability and an increase in endogenous calcium currents in PC12 cells. Moreover, both endogenous and expressed {gamma}7 are present on intracellular membranes, rather than the plasma membrane. The cytoplasmic C terminus of {gamma}7 is essential for all its effects, and we show that {gamma}7 binds directly via its C terminus to a heterogeneous nuclear ribonucleoprotein (hnRNP A2), which also binds to a motif in CaV2.2 mRNA, and is associated with native CaV2.2 mRNA in PC12 cells. The expression of hnRNP A2 enhances CaV2.2 IBa, and this enhancement is prevented by a concentration of {gamma}7 that alone has no effect on IBa. The effect of {gamma}7 is selective for certain mRNAs because it had no effect on {alpha}2{delta}-2 mRNA stability, but it decreased the mRNA stability for the potassium-chloride cotransporter, KCC1, which contains a similar hnRNP A2 binding motif to that in CaV2.2 mRNA. Our results indicate that {gamma}7 plays a role in stabilizing CaV2.2 mRNA

    Probiotics: Finding the Right Regulatory Balance

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    Some products marketed as drugs should be excused from Phase I trials, but safety and efficacy claims for dietary supplements should be more tightly regulated

    Symptom burden and unmet needs in MPM:exploratory analyses from the RESPECT-Meso study

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    © The Author(s) 2020. Objective: Malignant Pleural Mesothelioma (MPM) has a poor prognosis and high symptom burden. RESPECT-Meso was a multicenter randomized study examining the role of early specialist palliative care (SPC) on quality of life (QoL) with MPM. This is a post-hoc exploratory analysis of the symptom burden and unmet needs identified from RESPECT-Meso participants. Methods: Exploratory analysis from 174 participants using the General Health Status (GHS) measure (from the EORTC QLQ-C30 QoL questionnaire) and 87 participants using validated assessment questionnaires in those randomized to SPC. Eligibility for the study included confirmed MPM with diagnosis \u3c 6 weeks prior, performance score (PS) 0 or 1, no significant physical or psychological comorbidity. Cox proportional hazards models were derived to examine for relationships with survival. Free text was assessed using content analysis, looking for common themes and words. Results: Participants were predominantly male (79.9%), mean age 72.8 years, PS was 0 in 38%, 78% of MPM was epithelioid. At least 3 symptoms were reported in 69.8% of participants, including fatigue (81%), dyspnea (73.3%), pain (61.2%), weight loss (59.3%). Anxiety was reported by 54.7% of participants, 52.3% low mood and 48.8% anhedonia symptoms. After multivariable adjustment, only pain remained statistically significant with a hazard ratio (HR) 2.9 (95% CI 1.3-6.7; p = 0.01). For each 1 unit increase in GHS score, the HR for death was 0.987 (0.978-0.996; p = 0.006), indicating a worse reported QoL is related to shorter survival. Unmet needs were common: 25.9% wanted more information about their condition, 24.7% about their care and 21.2% about their treatment. 79.1% were concerned about the effect of their illness on family. Conclusion: There is a high symptom burden in mesothelioma despite good baseline performance status. A worse QoL is associated with a worse survival. Unmet needs are common, perhaps highlighting a need for improved communication and information sharing

    The Palmer LTER: A Long-Term Ecological Research Program at Palmer Station, Antarctica

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    THE ANTARCTIC marine ecosystem-the assemblage of plants, animals, ocean, sea ice, and island components south of the Antarctic Convergence is among the largest readily defined ecosystems on Earth (36 X 106 km2 ) (Hedgpeth, 1977; Petit et al., 1991). This ecosystem is composed of an interconnected system of functionally distinct hydrographic and biogeochemical subdivisions (Treguer and Jacques, 1992) and includes open ocean, frontal regions, shelf-slope waters, sea ice, and marginal ice zones. Oceanic, atmospheric, and biogeochemical processes within this system are thought to be globally significant, have been infrequently studied, and are poorly understood relative to more accessible marine ecosystems (Harris and Stonehouse, 1991; Johannessen et al., 1994). The Palmer Long-Term Ecological Research (Palmer LTER) area west of the Antarctic Peninsula (Fig. la) is a complex combination of a coastal/continental shelf zone and a seasonal sea ice zone, because this area is swept by the yearly advance and retreat of sea ice. The Palmer LTER program is a multidisciplinary program established to study this polar marine ecosystem

    Endothelin receptor antagonism does not prevent the development of in vivo glyceryl trinitrate tolerance in the rat

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    ABSTRACT There is evidence that increased endothelial production of endothelin-1 (ET-1) may contribute to glyceryl trinitrate (GTN) tolerance. We used the competitive ET A receptor antagonist ZD2574 to determine whether chronic ET A receptor blockade affected the biochemical and functional responses to GTN during the development of GTN tolerance in vivo. Tolerance induced using transdermal GTN patches resulted in a 5.3 Ϯ 1.2-fold increase in the EC 50 value for GTN relaxation in isolated aorta from GTN-tolerant rats. Coadministration of ZD2574 (100 mg kg Ϫ1 t.i.d. for 3 days) during tolerance induction had no effect on GTN-induced relaxation. This dose of ZD2574 markedly blunted the pressor response to ET-1, indicating effective blockade of ET A receptors, and also abolished the initial transient depressor response to ET-1, indicating that blockade of endothelial ET B receptors also occurred using this dosage regimen for ZD2574. Consistent with the relaxation data, coadministration of ZD2574 had no effect on the decrease in GTNinduced cGMP accumulation or on the decrease in GTN biotransformation that occurred in aortae from GTN-tolerant animals. Radioimmunoassay data indicated that the GTN tolerance induction protocol caused a 2.3 Ϯ 0.4-fold and a 2.2 Ϯ 0.5-fold increase in total tissue ET-1 levels in tolerant aorta and vena cava, respectively. These data suggest that chronic inhibition of ET receptors by ZD2574 was not sufficient to prevent or diminish the tolerance-inducing effects of GTN, and that the increase in ET-1 levels observed in tolerant tissues may occur as a consequence of the vascular changes that occur during chronic GTN exposure

    SDSS-IV MaNGA: spatially resolved dust attenuation in spiral galaxies

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    Dust attenuation in star-forming spiral galaxies affects stars and gas in different ways due to local variations in dust geometry. We present spatially resolved measurements of dust attenuation for a sample of 232 such star-forming spiral galaxies, derived from spectra acquired by the SDSS-IV MaNGA survey. The dust attenuation affecting the stellar populations of these galaxies (obtained using full spectrum stellar population fitting methods) is compared with the dust attenuation in the gas (derived from the Balmer decrement). Both of these attenuation measures increase for local regions of galaxies with higher star formation rates; the dust attenuation affecting the stellar populations increases more so than the dust attenuation in the gas, causing the ratio of the dust attenuation affecting the stellar populations to the dust attenuation in the gas to decrease for local regions of galaxies with higher star formation rate densities. No systematic difference is discernible in any of these dust attenuation quantities between the spiral arm and inter-arm regions of the galaxies. While both the dust attenuation in the gas and the dust attenuation affecting the stellar populations decrease with galactocentric radius, the ratio of the two quantities does not vary with radius. This ratio does, however, decrease systematically as the stellar mass of the galaxy increases. Analysis of the radial profiles of the two dust attenuation measures suggests that there is a disproportionately high concentration of birth clouds (incorporating gas, young stars and clumpy dust) nearer to the centres of star-forming spiral galaxies.Comment: 17 pages, 8 figures, accepted for publication in Monthly Notices of the Royal Astronomical Societ

    Validation of self-reported anthropometrics in the Adventist Health Study 2

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    <p>Abstract</p> <p>Background</p> <p>Relying on self-reported anthropometric data is often the only feasible way of studying large populations. In this context, there are no studies assessing the validity of anthropometrics in a mostly vegetarian population. The objective of this study was to evaluate the validity of self-reported anthropometrics in the Adventist Health Study 2 (AHS-2).</p> <p>Methods</p> <p>We selected a representative sample of 911 participants of AHS-2, a cohort of over 96,000 adult Adventists in the USA and Canada. Then we compared their measured weight and height with those self-reported at baseline. We calculated the validity of the anthropometrics as continuous variables, and as categorical variables for the definition of obesity.</p> <p>Results</p> <p>On average, participants underestimated their weight by 0.20 kg, and overestimated their height by 1.57 cm resulting in underestimation of body mass index (BMI) by 0.61 kg/m<sup>2</sup>. The agreement between self-reported and measured BMI (as a continuous variable), as estimated by intraclass correlation coefficient, was 0.97. The sensitivity of self-reported BMI to detect obesity was 0.81, the specificity 0.97, the predictive positive value 0.93, the predictive negative value 0.92, and the Kappa index 0.81. The percentage of absolute agreement for each category of BMI (normoweight, overweight, and obese) was 83.4%. After multivariate analyses, predictors of differences between self-reported and measured BMI were obesity, soy consumption and the type of dietary pattern.</p> <p>Conclusions</p> <p>Self-reported anthropometric data showed high validity in a representative subsample of the AHS-2 being valid enough to be used in epidemiological studies, although it can lead to some underestimation of obesity.</p
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