Components required for in vitro cleavage and polyadenylation of eukaryotic mRNA

We have studied in vitro cleavage/polyadenylation of precursor RNA containing herpes simplex virus type 2 poly A site sequences and have analysed four RNA/protein complexes which form during in vitro reactions. Two complexes, A and B, form extremely rapidly and are then progressively replaced by a third complex, C which is produced following cleavage and polyadenylation of precursor RNA. Substitution of ATP with cordycepin triphosphate prevents polyadenylation and the formation of complex C however a fourth complex, D, results which contains cleaved RNA. A precursor RNA lacking GU-rich downstream sequences required for efficient cleavage/ polyadenylation fails to form complex B and produces a markedly reduced amount of complex A. As these GU-rich sequences are required for efficient cleavage, this establishes a relationship between complex B formation and cleavage/polyadenylation of precursor RNA in vitro. The components required for in vitro RNA processing have been separated by fractionation of the nuclear extract on Q-Sepharose and Biorex 70 columns. A Q-Sepharose fraction forms complex B but does not process RNA. Addition of a Biorex 70 fraction restores cleavage activity at the poly A site but this fraction does not appear to contribute to complex formation. Moreover, in the absence of polyethylene glycol, precursor RNA is not cleaved and polyadenylated, however, complexes A and B readily form. Thus, while complex B is necessary for in vitro cleavage and polyadenylation, it may not contain all the components required for this processing

High temporal resolution sampling reveals reef fish settlement is highly clustered

Coral reef fish larvae settle on reefs predominantly at night around the new-moon phase, after an early developmental period spent in the pelagic environment. Most sampling is conducted across whole nights, and any studies that have examined the frequency of arrival within nights have typically been limited to coarse sampling time scales of 1–5 h. Here, we present results for arrival numbers of fish caught between dusk and midnight from light traps sampled every 15 min at an Indonesian coral reef, providing the finest temporal resolution for this type of study to date. A spatial analysis by distance indices analysis, adapted to temporal data, revealed clustering of reef arrival times for many species, with an increase in catches immediately after dusk dropping off towards midnight. Importantly, the timing of clusters differed among species, indicating that different factors determine the timing of arrival among taxa. Our results support the hypothesis that larval behaviour influences the timing of arrival at a coral reef for different fish species

No increased risk of cardiovascular events in older adults initiating dipeptidyl peptidase-4 inhibitors vs therapeutic alternatives

Aim: To compare the cardiovascular (CV) risk associated with dipeptidyl peptidase-4 (DPP-4) inhibitors relative to sulphonylureas (SUs) and thiazolidinediones (TZDs). Methods: During 2007 to 2013, using Medicare data for beneficiaries aged >65 years, we identified the following 2 cohorts of new-users, who had not been exposed to the drugs being compared in the 6 months before initiation: (1) DPP-4 inhibitor vs SU initiators and (2) DPP-4 inhibitor vs TZD initiators. Using propensity-score-adjusted Cox models accounting for competing risk by death, we estimated the hazard ratios (HRs), risk differences and 95% confidence intervals (CIs) for myocardial infarction (MI), stroke, hospitalization for heart failure (HF), and a combined outcome (MI, stroke, all-cause mortality). Results: In the DPP-4 inhibitor vs SU comparison, there were 30 130 DPP-4 inhibitor initiators and 68 382 SU initiators. Their mean age was 75 years, 41% were men and 55% had a baseline CV condition. The HR for the composite outcome was 0.75 (95% CI 0.72-0.79) over a median treatment duration of 1 year, but the 1-year risks of MI were 1.00 (95% CI 0.89-1.12) and 1.47 (95% CI 1.38-1.56) per 100 patients for DPP-4 inhibitors and SUs, respectively, and the corresponding stroke risks were 0.98 (95% CI 0.87-1.10) and 1.09 (95% CI 1.01-1.17). For the DPP-4 inhibitor vs TZD comparison, there were 20 596 DPP-4 inhibitor initiators and 13 526 TZD initiators without previous HF. Their mean age was 74 years, 42% were men and 30% had a baseline CV event. The composite outcome HR was 0.94 (95% CI 0.86-1.02) over a median treatment duration of 1 year. The 1-year risk for MI was ~0.90 and for stroke it was ~0.80 per 100 patients in both DPP-4 inhibitor and TZD initiators. Conclusion: Although limited by the short treatment period, the present study suggests there is no increased short-term risk of MI, stroke or HF with DPP-4 inhibitors vs SUs/TZDs

Calendar time as an instrumental variable in assessing the risk of heart failure with antihyperglycemic drugs

Objective: In recent years, second-line diabetes treatment with dipeptidyl peptidase–4 inhibitors (DPP-4i) increased with a corresponding decrease in thiazolidinediones (TZDs). Using hospitalization for heart failure (HF) as a positive control outcome, we explored the use of calendar time as an instrumental variable (IV) and compared this approach to an active comparator new-user study. Methods: We identified DPP-4i or TZD initiators after a 6-month washout using Medicare claims 2006–2013. The IV was defined as a binary variable comparing initiators during October 2010 to December 2013 (postperiod) versus January 2008 to May 2010 (preperiod). We examined IV strength and estimated risk differences (RDs) for HF using Kaplan-Meier curves, which were compared with propensity score (PS)–weighted RD for DPP-4i versus TZD. Results: The IV compared 22 696 initiators (78% DPP-4i) in the postperiod versus 20 283 initiators (38% DPP-4i) in the preperiod, resulting in 40% compliance. The active-comparator (PS-weighted) approach compared 26 198 DPP-4i and 18 842 TZD initiators. Covariate balance across IV levels was slightly better than across treatments (standardized difference, 3% vs 4.5%). The 1- and 2-year local average treatment effects of RD of HF per 100 patients in the “compliers” (95% confidence intervals) were −0.62 (−0.99 to −0.25) and −0.88 (−1.46 to −0.25). Corresponding PS-weighted results were −0.20 (−0.33 to −0.05) and −0.18 (−0.30 to 0.03). Conclusion: Both approaches indicated lesser risk of HF hospitalizations among DPP-4i vs TZD initiators. The magnitude of the estimated effects may differ due to differences in the target populations and assumptions. Calendar time can be leveraged as an IV when market dynamics lead to profound changes in treatments

The impact of liraglutide on diabetes-related foot ulceration and associated complications in patients with type 2 diabetes at high risk for cardiovascular events: Results from the LEADER trial

OBJECTIVE: Diabetes-related foot ulcers (DFUs) and their sequelae result in large patient and societal burdens. Long-term data determining the efficacy of individual glucose-lowering agents on DFUs are lacking. Using existing data from the Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results (LEADER) trial, we conducted post hoc analyses assessing the impact of liraglutide versus placebo in people with type 2 diabetes and at high risk of cardiovascular (CV) events on the incidence of DFUs and their sequelae. RESEARCH DESIGN AND METHODS: The LEADER trial (NCT01179048) was a randomized, double-blind, multicenter, CV outcomes trial assessing liraglutide (1.8 mg/day) versus placebo, in addition to standard of care, for up to 5 years. Information on DFUs was collected systematically during the trial, and DFU complications were assessed post hoc through reviewing case narratives. RESULTS: During a median of 3.8 years' follow-up, similar proportions of patients reported at least one episode of DFU in the liraglutide and placebo groups (3.8% [176/4,668] versus 4.1% [191/4,672], respectively; hazard ratio [HR] 0.92 [95% CI 0.75, 1.13; P = 0.41]). Analysis of DFU-related complications demonstrated a significant reduction in amputations with liraglutide versus placebo (HR 0.65 [95% CI 0.45, 0.95; P = 0.03]). However, no differences were found for foot infections, involvement of underlying structures, or peripheral revascularization in the main analysis. CONCLUSIONS: Treatment with liraglutide in patients with type 2 diabetes and at high risk of CV events in the LEADER trial did not increase the risk of DFU events and was associated with a significantly lower risk of DFU-related amputations compared with placebo. This association, possibly due to chance, needs further investigation

Familial Occurrence of Multiple Sclerosis with Thyroid Disease and Systemic Lupus Erythematosus

Multiple sclerosis (MS) has some features which suggest it is an autoimmune disease. Autoimmune diseases frequently occur in families, and patients and families often have more than one type of autoimmune disease. However, there are few reports of MS occurring in patients or families with other autoimmune conditions. It is difficult to make a separate diagnosis of MS in a patient who has a systemic autoimmune disease such as systemic lupus erythematosus (SLE) or Sjogren's syndrome, because these diseases can affect the nervous system directly. However, it is possible to make independent diagnoses of MS and an autoimmune disease confined to another single organ in the same patient, or diagnoses of MS and SLE (or other autoimmune diseases) in different family members. Here we describe clinically definite MS in 2 sisters, one of whom had Graves' disease, and the other of whom had a daughter with SLE and with a high titre of anti-thyroid antibodies. Other female family members over 4 generations had histories of thyroid disease, MS and Addison's disease. Available family members were HLA typed. The MS patients were positive for HLA DR2. All but one of the affected family members were related to the proband on the maternal side, and all of these affected females shared an HLA haplotype. However, this haplotype was also present in unaffected individuals. Thus HLA type alone cannot account for the familial occurrence of these disorders. We conclude that, in this family, MS, like autoimmune thyroid disease and SLE, may be an autoimmune disease developing in genetically predisposed individuals

A radium assay technique using hydrous titanium oxide adsorbent for the Sudbury Neutrino Observatory

As photodisintegration of deuterons mimics the disintegration of deuterons by neutrinos, the accurate measurement of the radioactivity from thorium and uranium decay chains in the heavy water in the Sudbury Neutrino Observatory (SNO) is essential for the determination of the total solar neutrino flux. A radium assay technique of the required sensitivity is described that uses hydrous titanium oxide adsorbent on a filtration membrane together with a beta-alpha delayed coincidence counting system. For a 200 tonne assay the detection limit for 232Th is a concentration of 3 x 10^(-16) g Th/g water and for 238U of 3 x 10^(-16) g U/g water. Results of assays of both the heavy and light water carried out during the first two years of data collection of SNO are presented.Comment: 12 pages, 4 figure

Effects of Cooking in Solutions of Varying pH on the Dietary Fiber Components of Vegetables

To study the effect of pH on dietary fiber components of vegetables, beans, cauliflower, potatoes, peas and corn were cooked in buffers of pH 2, 4, 6, and 10. Water-soluble pectin and hemicellulose, water-insoluble pectin and hemicellulose, cellulose and lignin were quantitated in raw, cooked vegetables and cooking medium. Tenderness and pH of raw and cooked vegetables were determined. Texture varied with cooking medium. Cooked vegetables were most firm at pH 4 and softest at pH 10. Dietary components found in cooking medium reflected these textural changes. Vegetables which showed greater pH effects exhibited greater changes in fiber components.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73821/1/j.1365-2621.1984.tb13237.x.pd

Attentive Learning of Sequential Handwriting Movements: A Neural Network Model

Defense Advanced research Projects Agency and the Office of Naval Research (N00014-95-1-0409, N00014-92-J-1309); National Science Foundation (IRI-97-20333); National Institutes of Health (I-R29-DC02952-01)