Annihilation, Rescattering, and CP Asymmetries in B Meson Decays

A number of $B$ meson decays may proceed only through participation of the spectator quark, whether through amplitudes proportional to $f_B/m_B$ or via rescattering from other less-suppressed amplitudes. An expected hierarchy of amplitudes in the absence of rescattering will be violated by rescattering corrections. Such violations could point the way toward channels in which final-state interactions could be important. Cases in which final state phases can lead to large CP asymmetries are pointed out.Comment: 9 page

Chronic kidney disease and valvular heart disease: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies conference

Chronic kidney disease (CKD) is a major risk factor for valvular heart disease (VHD). Mitral annular and aortic valve calcifications are highly prevalent in CKD patients and commonly lead to valvular stenosis and regurgitation, as well as complications including conduction system abnormalities and endocarditis. VHD, especially mitral regurgitation and aortic stenosis, is associated with significantly reduced survival among CKD patients. Knowledge related to VHD in the general population is not always applicable to CKD patients because the pathophysiology may be different, and CKD patients have a high prevalence of comorbid conditions and elevated risk for periprocedural complications and mortality. This Kidney Disease: Improving Global Outcomes (KDIGO) review of CKD and VHD seeks to improve understanding of the epidemiology, pathophysiology, diagnosis, and treatment of VHD in CKD by summarizing knowledge gaps, areas of controversy, and priorities for research

Is progression of coronary artery calcification influenced by modality of renal replacement therapy? : A systematic review

Background: Progression of coronary artery calcification is an important marker for cardiovascular morbidity in end-stage renal disease patients. Therefore, we reviewed the evidence on coronary artery calcification progression in different renal replacement therapies. Methods: MEDLINE (PubMed), Embase and TRIP databases were searched from 1999 - 2016. Additionally, bibliographies were searched by hand and citation tracking of key publications was performed. Prospective studies were included that examined coronary artery calcification with two or more multislice computed tomography scans ≥6 months apart in patients 18-75 years old receiving any renal replacement therapy, including kidney transplantation. Reporting of separate scores for different modalities was required. Two researchers extracted data independently with pilot-tested forms and assessed the risk of bias using a validated tool. Results: We identified 29 eligible studies that assessed coronary artery calcification progression in end-stage renal disease patients, of which 19 studies evaluated haemodialysis and 8 kidney transplantation. Evidence on progression in peritoneal dialysis (three studies) and nocturnal haemodialysis (one study) was limited. Meta-analysis was not possible due to diverse reporting methods of coronary artery calcification scores and definitions of progression. Median coronary artery calcification scores were considerably higher in haemodialysis cohorts at baseline, presumably due to a generally higher age and dialysis vintage. Median coronary artery calcification progressed universally. Visual inspection suggested the least progression in kidney transplant recipients. Conclusions: There is insufficient evidence to compare the influence of renal replacement therapies on coronary artery calcification progression. We advocate the adoption of a standardized reporting method of coronary artery calcification progression

Local shear stress and brachial artery functions in end-stage renal disease

Physiologic laminar shear stress (SS) is crucial for normal vascular structure and function. As a result of anemia-related lower whole-blood viscosity (WBV), SS could be reduced in patients with ESRD and might be associated with arterial functional alterations. In 44 patients with ESRD and 25 control subjects, brachial artery (BA) compliance and BA diameter changes (flow-mediated dilation [FMD[) were evaluated in response to local shear rate and SS changes during hand warming-induced hyperemia. Patients with ESRD and control subjects had similar BA blood flow, but SS was lower in patients with ESRD (P < 0.001), with lower shear rate (P < 0.01) and lower WBV (P < 0.0001). In control subjects, SS was positively (and physiologically) correlated with arterial diameter (P < 0.001). In contrast, in patients with ESRD, larger arterial diameter was associated with low SS (P < 0.05) and increased arterial wall elastic modulus (P < 0.001). Anemia-associated low WBV aggravates low shear rate, further contributing to SS reduction. These abnormalities were associated with decreased vasodilating response to endothelial mechanical stimulation. Compared with control subjects, BA compliance and FMD increases in response to hand warming-induced increased SS were lower in ESRD patients (P < 0.01), whereas their BA diameter response to glyceryl trinitrate did not differ. The long-term WBV and SS increases after anemia correction improved FMD (P < 0.01) and BA compliance (P < 0.05) and heightened arterial wall sensitivity to mechanical stimulation. Maintenance low SS as a result of anemia could play an indirect role in arterial dysfunction in patients with ESRD

Selective reduction of cardiac mass and central blood pressure on low-dose combination perindopril/indapamide in hypertensive subjects.

OBJECTIVE: In hypertension, blockade of the renin-angiotensin system reduces left ventricular mass (LVM) independently of brachial systolic (S), diastolic (D), and mean (M) blood pressure (BP). From central to peripheral arteries, MBP and DBP are practically unchanged, whereas SBP and pulse pressure (PP) increase significantly. The objective was to determine whether changes in LVM under drug treatment was preferentially associated with changes in central or brachial SBP and PP. DESIGN: A substudy of 146 subjects was selected from 469 hypertensive patients submitted to a double-blind randomized trial comparing the combination of perindopril (2 mg; Per) and indapamide (0.625 mg; Ind) with atenolol (50 mg, one tablet per day). MAIN OUTCOME MEASURES: Before and after 1 year of treatment: LVM (echocardiography) in 146 subjects and, in 52 of them, central (carotid) BP and timing of wave reflections (tonometry). RESULTS: LVM changes were significantly associated with antihypertensive treatment, with lower LVM with Per/Ind than with atenolol. Changes in SBP and PP, but not in MBP and DBP, were more significantly associated with Per/Ind than with atenolol, with more pronounced effects using central than brachial measurements, and a longer delay in central return of wave reflections under Per/Ind. In the sampling of 52 patients with tonometry, the change in LVM between the two drug regimens was significantly linked to central, but not brachial, PP change. CONCLUSIONS: This observational study shows a lower LVM under Per/Ind than under atenolol. The greater change in LVM on Per/Ind was linked to central and not brachial blood pressure