Background High blood pressure is common in acute stroke and is a predictor of poor outcome; however, large trials of lowering blood pressure have given variable results, and the management of high blood pressure in ultra-acute stroke remains unclear. We investigated whether transdermal glyceryl trinitrate (GTN; also known as nitroglycerin), a nitric oxide donor, might improve outcome when administered very early after stroke onset. Methods We did a multicentre, paramedic-delivered, ambulance-based, prospective, randomised, sham-controlled, blinded-endpoint, phase 3 trial in adults with presumed stroke within 4 h of onset, face-arm-speech-time score of 2 or 3, and systolic blood pressure 120 mm Hg or higher. Participants were randomly assigned (1:1) to receive transdermal GTN (5 mg once daily for 4 days; the GTN group) or a similar sham dressing (the sham group) in UKbased ambulances by paramedics, with treatment continued in hospital. Paramedics were unmasked to treatment, whereas participants were masked. The primary outcome was the 7-level modified Rankin Scale (mRS; a measure of functional outcome) at 90 days, assessed by central telephone follow-up with masking to treatment. Analysis was hierarchical, first in participants with a confirmed stroke or transient ischaemic attack (cohort 1), and then in all participants who were randomly assigned (intention to treat, cohort 2) according to the statistical analysis plan. This trial is registered with ISRCTN, number ISRCTN26986053.

SummaryBackgroundIntensive antiplatelet therapy with three agents might be more effective than guideline treatment for preventing recurrent events in patients with acute cerebral ischaemia. We aimed to compare the safety and efficacy of intensive antiplatelet therapy (combined aspirin, clopidogrel, and dipyridamole) with that of guideline-based antiplatelet therapy.MethodsWe did an international, prospective, randomised, open-label, blinded-endpoint trial in adult participants with ischaemic stroke or transient ischaemic attack (TIA) within 48 h of onset. Participants were assigned in a 1:1 ratio using computer randomisation to receive loading doses and then 30 days of intensive antiplatelet therapy (combined aspirin 75 mg, clopidogrel 75 mg, and dipyridamole 200 mg twice daily) or guideline-based therapy (comprising either clopidogrel alone or combined aspirin and dipyridamole). Randomisation was stratified by country and index event, and minimised with prognostic baseline factors, medication use, time to randomisation, stroke-related factors, and thrombolysis. The ordinal primary outcome was the combined incidence and severity of any recurrent stroke (ischaemic or haemorrhagic; assessed using the modified Rankin Scale) or TIA within 90 days, as assessed by central telephone follow-up with masking to treatment assignment, and analysed by intention to treat. This trial is registered with the ISRCTN registry, number ISRCTN47823388.Findings3096 participants (1556 in the intensive antiplatelet therapy group, 1540 in the guideline antiplatelet therapy group) were recruited from 106 hospitals in four countries between April 7, 2009, and March 18, 2016. The trial was stopped early on the recommendation of the data monitoring committee. The incidence and severity of recurrent stroke or TIA did not differ between intensive and guideline therapy (93 [6%] participants vs 105 [7%]; adjusted common odds ratio [cOR] 0·90, 95% CI 0·67–1·20, p=0·47). By contrast, intensive antiplatelet therapy was associated with more, and more severe, bleeding (adjusted cOR 2·54, 95% CI 2·05–3·16, p<0·0001).InterpretationAmong patients with recent cerebral ischaemia, intensive antiplatelet therapy did not reduce the incidence and severity of recurrent stroke or TIA, but did significantly increase the risk of major bleeding. Triple antiplatelet therapy should not be used in routine clinical practice.FundingNational Institutes of Health Research Health Technology Assessment Programme, British Heart Foundation.

This randomized clinical trial evaluates the safety and efficacy of the monoclonal anti-tau antibody semorinemab in individuals with prodromal to mild Alzheimer disease.

Luteinizing hormone (LH) receptor mRNA is posttranscriptionally regulated. An ovarian cytosolic LH receptor mRNA-binding protein (LRBP) identified in our laboratory binds to a polypyrimidine-rich bipartite sequence in the coding region of LH receptor mRNA. The present studies show a role for LRBP in the regulation of LH receptor mRNA. We demonstrated that increased LH receptor mRNA degradation occurs during hormone-induced LH receptor down-regulation. Furthermore, increased degradation of LH receptor mRNA was seen when partially purified LRBP was included in an in vitro mRNA decay reaction. The LH receptor mRNA binding activity of LRBP measured by RNA electrophoretic mobility shift analysis showed an inverse relationship to LH receptor mRNA levels during different physiological states. These results suggest that LRBP is a physiological regulator of LHR mRNA expression in the ovary and provides a novel mechanism for the regulation of LH receptor expression in the ovary.The expression of luteinizing hormone receptors (LHR) 1 on the rat ovarian granulosa cells and luteal cells is decreased by an endogenous preovulatory luteinizing hormone (LH) surge or by the administration of a pharmacological dose of human chorionic gonadotropin (hCG), a placental counterpart of LH (1-4). Studies from our laboratory have demonstrated that the decline in cell surface LHR number seen after hCG administration is paralleled by a specific loss of LHR mRNA (2, 3). Following the injection of a bolus of hCG in female rat, a rapid decline in the steady-state levels of all four LHR mRNA transcripts (6.7, 4.4, 2.6, and 1.8 kb) is seen in luteal cells within 12 h with a complete loss occurring by 24 h. This selective loss is followed by a recovery of receptor mRNA expression between 24 and 48 h (2). We have shown that the loss of LHR mRNA does not result from decreased transcription but occurs posttranscriptionally with an approximate 3-fold decrease in halflife (4). Additional studies led to the identification of a 50-kDa LHR mRNA-binding protein designated as LRBP in rat and human ovarian cytosolic fractions. During hormone-induced down-regulation of the LHR, the LHR mRNA binding activity of LRBP was increased. LRBP specifically binds to the coding region of LHR mRNA with an apparent dissociation constant of 10 -9 M (5, 6). These studies were carried out to determine the role of LRBP in LHR mRNA degradation in vitro as well as to establish a relationship between LHR mRNA expression and LRBP during ovarian development. Our results show that LHR mRNA expression inversely correlates with the LHR mRNA binding activity of LRBP during follicular maturation, ovulation, and luteinization. Furthermore, a partially purified LRBP causes accelerated decay of LHR mRNA in an in vitro reconstituted mRNA decay system. MATERIALS AND METHODS Chemicals-Pregnant mare serum gonadotropin was purchased from Calbiochem. Human chorionic gonadotropin was obtained from Sigma. [␣-32 P]dCTP was purchased from ICN (Costa Mesa, CA), and [␣-32 P]UTP was from PerkinElmer ...

Post-transcriptional mechanisms play a major role in regulating luteinizing hormone (LH) receptor mRNA expression in the ovary. An ovarian cytosolic protein that we have identified in rats and humans, which binds to a polypyrimidine-rich bipartitate sequence in the coding region of LHR mRNA, acts as a trans-acting factor in this process. In the present study, we isolated and characterized this LH receptor mRNA-binding protein (LRBP) from rat ovary. LRBP was purified to homogeneity by cation exchange chromatography followed by Northwestern analysis and subsequent elution of the single protein band from SDS-polyacrylamide gel. Purified LRBP was subjected to N-terminal microsequencing followed by homology search, which revealed its identity as mevalonate kinase. Purified rat mevalonate kinase antibody recognized the gel-purified LRBP on Western blots performed with one-and two-dimensional SDSpolyacrylamide gels. When recombinant mevalonate kinase produced in human embryonic kidney cells ( The interaction of luteinizing hormone (LH) 1 with its cell surface receptors controls reproductive functions including steroidogenesis in the gonad (1). In the ovary, luteinizing hormone receptor (LHR), a member of G s -protein coupled receptors, regulates ovarian function mainly through increased production of cAMP (2-4). The cell surface expression of LHR varies during different stages of the ovarian cycle. Its expression in granulosa cells and luteal cells is greatly decreased by an endogenous preovulatory LH surge or by the administration of a pharmacological dose of human chorionic gonadotropin (hCG), a placental counterpart of LH (5-8). We have shown that the decline in cell surface LHR expression seen after hCG administration is paralleled by a specific loss of all four LHR mRNA transcripts (6.7, 4.4, 2.6, and 1.8 kb) in the ovary (9). Furthermore, the loss of LHR mRNA does not result from decreased transcription but occurs post-transcriptionally with a 3-fold decrease in half-life (8).Regulation of mRNA turnover is one of the major control mechanisms of gene expression in all organisms. mRNA halflives are influenced by the interaction of various cytoplasmic proteins (trans-acting factors) with regulatory regions (cis-acting elements) in the mRNA, forming ribonucleoprotein (RNP) complexes (10). The formation and disruption of RNP complexes in response to various cellular stimuli mainly controls the turnover of cytoplasmic mRNA. Studies have indicated the presence of cis-acting regulatory elements in the 5Ј-untranslated region, coding region, and 3Ј-untranslated region of mRNA (10). A number of cytoplasmic trans-acting factors, some of which shuttle between the nucleus and cytoplasm, have been identified as mRNA-stabilizing, destabilizing, or translational repressor proteins (11-16). c-Fos, c-Myc, tropoelastin, thymidylate synthase, and dihydrofolate reductase are some of the mRNAs containing regulatory elements in the coding region for trans-acting factors (17-24).We have identified a LHR mRNA-binding protein in rat and hu...

The LH/hCG receptor, a member of the G protein coupled receptor family mediates the cellular actions of LH in the ovary. A considerable amount of information regarding its structure, mechanism of activation, and regulation of expression has emerged in recent years. Here we provide a brief overview of the current information on the structural organization of the receptor and the mechanism of receptor mediated signaling as well as an in-depth discussion on recent developments pertaining to the regulation of receptor expression. Specifically, we describe studies from our laboratory showing that the posttranscriptional regulation of the receptor involves an LH/hCG receptor mRNA-binding protein. We also propose a model to explain the loss of steady-state LH/hCG receptor mRNA levels during receptor down-regulation.

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The missing data are not missing completely at random in ADNI and likely conditional on certain features in addition to cognitive function. Missing data predictors vary across biomarkers and even MCI and AD groups do not share the same missing data pattern. Understanding the missing data structure may help in the design of future longitudinal studies and clinical trials in AD.