A loss-of-function polymorphism in the human P2X4 receptor is associated with increased pulse pressure

The P2X4 receptor is involved in endothelium-dependent changes in large arterial tone in response to shear stress and is, therefore, potentially relevant to arterial compliance and pulse pressure. Four identified nonsynonymous polymorphisms in P2RX4 were reproduced in recombinantly expressed human P2X4. Electrophysiological studies showed that one of these, the Tyr315>Cys mutation (rs28360472), significantly reduced the peak amplitude of the ATP-induced inward current to 10.9% of wild-type P2X4 receptors in transfected HEK-293 cells (10 µmol/L of ATP; n=4-8 cells; P<0.001). Concentration-response curves for ATP and the partial agonist BzATP demonstrate that the 315Cys-P2X4 mutant had an increased EC50 value for both ligands. Mutation of Tyr315>Cys likely disrupts the agonist binding site of P2X4 receptors, a finding supported by molecular modeling based on the zebrafish P2X4 receptor crystal structure. We tested inheritance of rs28360472 encoding the Tyr315>Cys mutation in P2RX4 against pulse pressure in 2874 subjects from the Victorian Family Heart Study. The minor allele frequency was 0.014 (1.4%). In a variance components analysis we found significant association with pulse pressure (P=0.023 for total association) where 1 minor allele increased pulse pressure by 2.84 mm Hg (95% CI: 0.41-5.27). This increase in pulse pressure associated with inheritance of 315Cys-P2X4 receptors might reflect reduced large arterial compliance as a result of impaired endothelium-dependent vasodilation in large arteries

Follow-up of blood-pressure lowering and glucose control in type 2 diabetes.

BACKGROUND In the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) factorial trial, the combination of perindopril and indapamide reduced mortality among patients with type 2 diabetes, but intensive glucose control, targeting a glycated hemoglobin level of less than 6.5%, did not. We now report results of the 6-year post-trial follow-up. METHODS We invited surviving participants, who had previously been assigned to perindopril–indapamide or placebo and to intensive or standard glucose control (with the glucose-control comparison extending for an additional 6 months), to participate in a post-trial follow-up evaluation. The primary end points were death from any cause and major macrovascular events. RESULTS The baseline characteristics were similar among the 11,140 patients who originally underwent randomization and the 8494 patients who participated in the post-trial follow-up for a median of 5.9 years (blood-pressure–lowering comparison) or 5.4 years (glucose-control comparison). Between-group differences in blood pressure and glycated hemoglobin levels during the trial were no longer evident by the first post-trial visit. The reductions in the risk of death from any cause and of death from cardiovascular causes that had been observed in the group receiving active blood-pressure–lowering treatment during the trial were attenuated but significant at the end of the post-trial follow-up; the hazard ratios were 0.91 (95% confidence interval [CI], 0.84 to 0.99; P=0.03) and 0.88 (95% CI, 0.77 to 0.99; P=0.04), respectively. No differences were observed during follow-up in the risk of death from any cause or major macrovascular events between the intensive-glucose-control group and the standard-glucose-control group; the hazard ratios were 1.00 (95% CI, 0.92 to 1.08) and 1.00 (95% CI, 0.92 to 1.08), respectively. CONCLUSIONS The benefits with respect to mortality that had been observed among patients originally assigned to blood-pressure–lowering therapy were attenuated but still evident at the end of follow-up. There was no evidence that intensive glucose control during the trial led to long-term benefits with respect to mortality or macrovascular events

Long-term Benefits of Intensive Glucose Control for Preventing End-Stage Kidney Disease: ADVANCE-ON

OBJECTIVE The Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation (ADVANCE) trial reported that intensive glucose control prevents end-stage kidney disease (ESKD) in patients with type 2 diabetes, but uncertainty about the balance between risks and benefits exists. Here, we examine the long-term effects of intensive glucose control on risk of ESKD and other outcomes. RESEARCH DESIGN AND METHODS Survivors, previously randomized to intensive or standard glucose control, were invited to participate in post-trial follow-up. ESKD, defined as the need for dialysis or kidney transplantation, or death due to kidney disease, was documented overall and by baseline CKD stage, along with hypoglycemic episodes, major cardiovascular events, and death from other causes. RESULTS A total of 8,494 ADVANCE participants were followed for a median of 5.4 additional years. In-trial HbA1c differences disappeared by the first post-trial visit. The in-trial reductions in the risk of ESKD (7 vs. 20 events, hazard ratio [HR] 0.35, P = 0.02) persisted after 9.9 years of overall follow-up (29 vs. 53 events, HR 0.54, P 0.26). CONCLUSIONS Intensive glucose control was associated with a long-term reduction in ESKD, without evidence of any increased risk of cardiovascular events or death. These benefits were greater with preserved kidney function and with well-controlled blood pressure

Comparative effects of microvascular and macrovascular disease on the risk of major outcomes in patients with type 2 diabetes

Background Microvascular disease is associated with a high risk of macrovascular events in patients with type 2 diabetes, but the impact of macrovascular disease on the risk of microvascular events remains unknown. We sought to evaluate the respective effects of prior microvascular and macrovascular disease on the risk of major outcomes, including microvascular events, in these patients. Methods Participants in the Action in Diabetes and Vascular Disease: PreterAx and DiamicroN Modified-Release Controlled Evaluation (ADVANCE) trial (n = 11,140) and the ADVANCE-ON post-trial study (n = 8494) were categorized into 4 groups at baseline: dual absence of microvascular or macrovascular disease (n = 6789), presence of microvascular disease alone (n = 761), macrovascular disease alone (n = 3196), and both (n = 394). Outcomes were all-cause mortality, major macrovascular events (MACE), and major clinical microvascular events. Results All-cause mortality, MACE, and major clinical microvascular events occurred in 2265 (20%), 2166 (19%), and 807 (7%) participants respectively, during a median follow-up of 9.9 (inter-quartile interval 5.6–10.9) years. The adjusted hazard ratios [95% CI] of death, MACE, and major clinical microvascular events were each greater in patients with baseline microvascular disease (1.43 [1.20–1.71], 1.64 [1.37–1.97], and 4.74 [3.86–5.82], respectively), macrovascular disease (1.43 [1.30–1.57], 2.04 [1.86–2.25], and 1.26 [1.06–1.51]) or both (2.01 [1.65–2.45], 2.92 [2.40–3.55], and 6.30 [4.93–8.06]) compared with those without these conditions. No interaction was observed between baseline microvascular and macrovascular disease for these events. The addition of microvascular disease (change in c-statistic [95% CI] 0.005 [0.002–0.008], p = 0.02) or macrovascular disease (0.005 [0.002–0.007], p < 0.0001) considered separately or together (0.011 [0.007–0.014], p < 0.0001) improved the discrimination and the classification (integrated discrimination improvement (IDI): 0.013 [0.010–0.016], p < 0.001; net reclassification improvement (NRI): 0.021 [0.011–0.032], p < 0.001) of the risk of all-cause mortality. Microvascular disease improved discrimination (0.009 [0.003–0.014]) and classification (IDI: 0.008 [0.006–0.010]; NRI: 0.011 [0.001–0.020]) of MACE. Baseline macrovascular disease modestly enhanced IDI (0.002 [0.001–0.002]) and NRI (0.041 [0.002–0.087]), but not discrimination, of major clinical microvascular events. Conclusions Microvascular and macrovascular disease are independently associated with the 10-year risk of death, MACE, and major clinical microvascular events in patients with type 2 diabetes. The coexistence of these conditions was associated with the highest risks

Combined Effects of Routine Blood Pressure Lowering and Intensive Glucose Control on Macrovascular and Microvascular Outcomes in Patients With Type 2 Diabetes: New results from the ADVANCE trial

Item does not contain fulltextOBJECTIVE: To assess the magnitude and independence of the effects of routine blood pressure lowering and intensive glucose control on clinical outcomes in patients with long-standing type 2 diabetes. RESEARCH DESIGN AND METHODS: This was a multicenter, factorial randomized trial of perindopril-indapamide versus placebo (double-blind comparison) and intensive glucose control with a gliclazide MR-based regimen (target A1C 0.1): the separate effects of the two interventions for the renal outcomes and death appeared to be additive on the log scale. Compared with neither intervention, combination treatment reduced the risk of new or worsening nephropathy by 33% (95% CI 12-50%, P = 0.005), new onset of macroalbuminuria by 54% (35-68%, P < 0.0001), and new onset of microalbuminuria by 26% (17-34%). Combination treatment was associated with an 18% reduction in the risk of all-cause death (1-32%, P = 0.04). CONCLUSIONS: The effects of routine blood pressure lowering and intensive glucose control were independent of one another. When combined, they produced additional reductions in clinically relevant outcomes

Genetic basis of control of Rhynchosporium secalis infection and symptom expression in barley

The genetic basis of several different components of resistance to Rhynchosporium secalis in barley was investigated in a mapping population derived from a cross between winter and spring barley types. Both the severity of visual disease symptoms and amount of R. secalis DNA in leaf tissues were assessed in field trials in Scotland in the 2007/2008 and 2008/2009 growing seasons. Relative expression of symptoms was defined as the residual values from a linear regression of amount of R. secalis DNA against visual plot disease score at GS 50. Amount of R. secalis DNA and visual disease score were highly correlated traits and identified nearly identical QTL. The genetic control of relative expression of symptoms was less clear. However, a QTL on chromosome 7H was identified as having a significant effect on the expression of visual disease symptoms relative to overall amount of R. secalis colonisationPeer reviewedFinal Accepted Versio

Change in Blood Pressure Variability Among Treated Elderly Hypertensive Patients and Its Association With Mortality

Background: Information is scarce regarding effects of antihypertensive medication on blood pressure variability (BPV) and associated clinical outcomes. We examined whether antihypertensive treatment changes BPV over time and whether such change (decline or increase) has any association with long-term mortality in an elderly hypertensive population. Methods and Results: We used data from a subset of participants in the Second Australian National Blood Pressure study (n=496) aged ≥65 years who had 24-hour ambulatory blood pressure recordings at study entry (baseline) and then after a median of 2 years while on treatment (follow-up). Weighted day-night systolic BPV was calculated for both baseline and follow-up as a weighted mean of daytime and nighttime blood pressure standard deviations. The annual rate of change in BPV over time was calculated from these BPV estimates. Furthermore, we classified both BPV estimates as high and low based on the baseline median BPV value and then classified BPV changes into stable: low BPV, stable: high BPV, decline: high to low, and increase: low to high. We observed an annual decline (mean±SD: −0.37±1.95; 95% CI, −0.54 to −0.19; P<0.001) in weighted day-night systolic BPV between baseline and follow-up. Having constant stable: high BPV was associated with an increase in all-cause mortality (hazard ratio: 3.03; 95% CI, 1.67–5.52) and cardiovascular mortality (hazard ratio: 3.70; 95% CI, 1.62–8.47) in relation to the stable: low BPV group over a median 8.6 years after the follow-up ambulatory blood pressure monitoring. Similarly, higher risk was observed in the decline: high to low group. Conclusions: Our results demonstrate that in elderly hypertensive patients, average BPV declined over 2 years of follow-up after initiation of antihypertensive therapy, and having higher BPV (regardless of any change) was associated with increased long-term mortality