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Background— Na V 1.5 is a mechanosensitive voltage-gated sodium-selective ion channel responsible for the depolarizing current and maintenance of the action potential plateau in the heart. Ranolazine is a Na V 1.5 antagonist with antianginal and antiarrhythmic properties. Methods and Results— Mechanosensitivity of Na V 1.5 was tested in voltage-clamped whole cells and cell-attached patches by bath flow and patch pressure, respectively. In whole cells, bath flow increased peak inward current in both murine ventricular cardiac myocytes (24±8%) and human embryonic kidney 293 cells heterologously expressing Na V 1.5 (18±3%). The flow-induced increases in peak current were blocked by ranolazine. In cell-attached patches from cardiac myocytes and Na V 1.5-expressing human embryonic kidney 293 cells, negative pressure increased Na V peak currents by 27±18% and 18±4% and hyperpolarized voltage dependence of activation by −11 mV and −10 mV, respectively. In human embryonic kidney 293 cells, negative pressure also increased the window current (250%) and increased late open channel events (250%). Ranolazine decreased pressure-induced shift in the voltage dependence (IC 50 54 μmol/L) and eliminated the pressure-induced increases in window current and late current event numbers. Block of Na V 1.5 mechanosensitivity by ranolazine was not due to the known binding site on DIVS6 (F1760). The effect of ranolazine on mechanosensitivity of Na V 1.5 was approximated by lidocaine. However, ionized ranolazine and charged lidocaine analog (QX-314) failed to block mechanosensitivity. Conclusions— Ranolazine effectively inhibits mechanosensitivity of Na V 1.5. The block of Na V 1.5 mechanosensitivity by ranolazine does not utilize the established binding site and may require bilayer partitioning. Ranolazine block of Na V 1.5 mechanosensitivity may be relevant in disorders of mechanoelectric dysfunction.

To identify genes influencing blood pressure response to an angiotensin II receptor blocker, single nucleotide polymorphisms identified by genome-wide association analysis of the response to candesartan were validated by opposite direction associations with the response to a thiazide diuretic, hydrochlorothiazide. We sampled 198 white and 193 blacks with primary hypertension from opposite tertiles of the race-sex–specific distributions of age-adjusted diastolic blood pressure response to candesartan. There were 285 polymorphisms associated with the response to candesartan at P <10 −4 in whites. A total of 273 of the 285 polymorphisms, which were available for analysis in a separate sample of 196 whites, validated for opposite direction associations with the response to hydrochlorothiazide (Fisher χ 2 1-sided P =0.02). Among the 273 polymorphisms, those in the chromosome 11q21 region were the most significantly associated with response to candesartan in whites (eg, rs11020821 near FUT4 , P =8.98×10 −7 ), had the strongest opposite direction associations with response to hydrochlorothiazide (eg, rs3758785 in GPR83 , P =7.10×10 −3 ), and had the same direction associations with response to candesartan in the 193 blacks (eg, rs16924603 near FUT4 , P =1.52×10 −2 ). Also notable among the 273 polymorphisms was rs11649420 on chromosome 16 in the amiloride-sensitive sodium channel subunit SCNN1G involved in mediating renal sodium reabsorption and maintaining blood pressure when the renin-angiotensin system is inhibited by candesartan. These results support the use of genomewide association analyses to identify novel genes predictive of opposite direction associations with blood pressure responses to inhibitors of the renin-angiotensin and renal sodium transport systems.

What's known on the subject? and What does the study add? Postoperative complications for open radical nephrectomy ( ORN ), laparoscopic radical nephrectomy ( LRN ), and open partial nephrectomy ( OPN ) and its relationship with hospitalisation costs and mortality remain poorly described. The present population‐based study suggests modest differences in postoperative complications estimated at 27%, 23%, and 24% among patients with kidney cancer undergoing ORN , LRN , and OPN , respectively. Moreover, postoperative complications were associated with higher mortality, length of stay and total costs of hospitalisation. Objectives The association of complications after renal surgery for renal cell carcinoma ( RCC ) with in‐hospital mortality and costs remains to be defined. To describe the incidence of complications after open radical nephrectomy ( ORN ), laparoscopic RN ( LRN ), and open partial nephrectomy ( OPN ); and to evaluate its relationship with in‐hospital mortality and total costs. Patients and Methods We identified 49 983 individuals who underwent ORN (35 712), LRN (5327), or OPN (8944) for RCC at 2037 hospitals from the Nationwide Inpatient Sample 2001–2008. The outcomes assessed were in‐hospital mortality and total hospitalisation costs. Multivariable logistic regression and generalised estimating equations were used to test the associations between complications and in‐hospital mortality and total costs. Results With 26.0% of patients experiencing postoperative complications, there were modest differences in the proportion of patients with complications after ORN , LRN , and OPN at 27.0%, 22.6%, and 24.0%, respectively ( P < 0.001). After adjusting for patient and hospital variables, postoperative complications resulted in higher odds of in‐hospital death for ORN (odds ratio [ OR ] 7.20; P < 0.001), LRN ( OR 12.04; P < 0.001), and OPN ( OR 7.82; P < 0.001). Adjusted total costs also rose significantly with the presence of any postoperative complications compared with those without any complications for ORN ($21 242 vs $13 183; P < 0.001), LRN ($19 548 vs $12 555; P < 0.001), and OPN ($18 883 vs $12 098; P < 0.001). Conclusions With about a quarter of patients experiencing postoperative complications, adverse events for ORN , LRN , and OPN carry a significant risk of in‐hospital death and higher total costs. Efforts to reduce postoperative complications may correlate with substantial reductions in hospital mortality and total costs.

Abstract Background: Current management of lung nodules is complicated by nontherapeutic resections and missed chances for cure. We hypothesized that a serum proteomic signature may add diagnostic information beyond that provided by combined clinical and radiographic data. Methods: Cohort A included 265 and cohort B 114 patients. Using multivariable logistic regression analysis we calculated the area under the receiver operating characteristic curve (AUC) and quantified the added value of a previously described serum proteomic signature beyond clinical and radiographic risk factors for predicting lung cancer using the integration discrimination improvement (IDI) index. Results: The average computed tomography (CT) measured nodule size in cohorts A and B was 37.83 versus 23.15 mm among patients with lung cancer and 15.82 versus 17.18 mm among those without, respectively. In cohort A, the AUC increased from 0.68 to 0.86 after adding chest CT imaging variables to the clinical results, but the proteomic signature did not provide meaningful added value. In contrast, in cohort B, the AUC improved from 0.46 with clinical data alone to 0.61 when combined with chest CT imaging data and to 0.69 after adding the proteomic signature (IDI of 20% P = 0.0003). In addition, in a subgroup of 100 nodules between 5 and 20 mm in diameter, the proteomic signature added value with an IDI of 15% (P ≤ 0.0001). Conclusions: The results show that this serum proteomic biomarker signature may add value to the clinical and chest CT evaluation of indeterminate lung nodules. Impact: This study suggests a possible role of a blood biomarker in the evaluation of indeterminate lung nodules. Cancer Epidemiol Biomarkers Prev; 21(5); 786–92. ©2012 AACR.

Abstract Rationale The course of lung function decline for smokers with early airflow obstruction remains undefined. It is also unclear which early spirometric characteristics identify individuals at risk for rapid decline and increased mortality. Objectives To determine the association between spirometric measures and 5-year decline in FEV1 and 12-year mortality. Methods We analyzed longitudinal data from the Lung Health Study, a clinical trial of intensive smoking cessation intervention with or without bronchodilator therapy in 5,887 smokers with mild to moderate airflow obstruction. Participants were stratified into bins of baseline FEV1 to FVC ratio, using bins of 5%, and separately into bins of Z-score (difference between actual and predicted FEV1/FVC, normalized to SD of predicted FEV1/FVC). Associations between spirometric measures and FEV1 decline and mortality were determined after adjusting for baseline characteristics and time-varying smoking status. Measurements and Main Results The cohort was approximately two-thirds male, predominantly of white race (96%), and with mean age of 49 ± 7 years. In general, individuals with lower lung function by any metric had more rapid adjusted FEV1 decline. A threshold for differential decline was present at FEV1/FVC less than 0.65 (P &lt; 0.001) and Z-score less than −2 (2.3 percentile) (P &lt; 0.001). At year 12, 575 (7.2%) of the cohort had died. Lower thresholds of each spirometric metric were associated with increasing adjusted hazard of death. Conclusions Smokers at risk or with mild to moderate chronic obstructive pulmonary disease have accelerated lung function decline. Individuals with lower baseline FEV1/FVC have more rapid decline and worse mortality.