H,K-ATPase type 2 contributes to salt-sensitive hypertension induced by K(+) restriction.

In industrialized countries, a large part of the population is daily exposed to low K(+) intake, a situation correlated with the development of salt-sensitive hypertension. Among many processes, adaptation to K(+)-restriction involves the stimulation of H,K-ATPase type 2 (HKA2) in the kidney and colon and, in this study, we have investigated whether HKA2 also contributes to the determination of blood pressure (BP). By using wild-type (WT) and HKA2-null mice (HKA2 KO), we showed that after 4 days of K(+) restriction, WT remain normokalemic and normotensive (112 ± 3 mmHg) whereas HKA2 KO mice exhibit hypokalemia and hypotension (104 ± 2 mmHg). The decrease of BP in HKA2 KO is due to the absence of NaCl-cotransporter (NCC) stimulation, leading to renal loss of salt and decreased extracellular volume (by 20 %). These effects are likely related to the renal resistance to vasopressin observed in HKA2 KO that may be explained, in part by the increased production of prostaglandin E2 (PGE2). In WT, the stimulation of NCC induced by K(+)-restriction is responsible for the elevation in BP when salt intake increases, an effect blunted in HKA2-null mice. The presence of an activated HKA2 is therefore required to limit the decrease in plasma [K(+)] but also contributes to the development of salt-sensitive hypertension

Pulse Shape Estimation in a DSR Fiber Laser Using the Genetic Algorithm

Exploiting the computing power of the genetic algorithm, a numerical study of dissipative soliton resonance (DSR) in a ring laser mode-locked by a real saturable absorber (SA) is conducted. A section of photonic crystal fiber (PCF) is inserted into the laser cavity design to facilitate accurate control of both dispersion and nonlinearity. The influence of the cavity parameters on the evolution of the DSR pulses is systematically analyzed. The genetic algorithm demonstrates that the generation of DSR square pulses depends directly on the PCF dispersion, the PCF nonlinearity, the PCF length, and the modulation depth of the SA. Finally, the sensitivity of the DSR pulse width, peak power and energy to perturbations in a few key design parameters are highlighted

Pulse Shape Estimation in a DSR Fiber Laser Using the Genetic Algorithm

Exploiting the computing power of the genetic algorithm, a numerical study of dissipative soliton resonance (DSR) in a ring laser mode-locked by a real saturable absorber (SA) is conducted. A section of photonic crystal fiber (PCF) is inserted into the laser cavity design to facilitate accurate control of both dispersion and nonlinearity. The influence of the cavity parameters on the evolution of the DSR pulses is systematically analyzed. The genetic algorithm demonstrates that the generation of DSR square pulses depends directly on the PCF dispersion, the PCF nonlinearity, the PCF length, and the modulation depth of the SA. Finally, the sensitivity of the DSR pulse width, peak power and energy to perturbations in a few key design parameters are highlighted

Co-inhibitory receptors in female asthmatic patients: Correlation with IL-17 and IL-26

Background: Asthma is an immunological disorder in which T helper 2 (Th2)-type cells and inflammatory cytokines have a prominent role in its pathogenesis. B- and T-lymphocyte attenuator (BTLA), cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed death 1 (PD-1) are co-inhibitory receptors that regulate T cell activation. Objective: In the present study of asthmatic patients we measured the soluble isoforms of BTLA (sBTLA), CTLA-4 (sCTLA-4) and PD-1 (sPD-1) in induced sputum fluid with the aim to evaluate their utility as responsible for exacerbation. Methods: Eighty patients with asthma and 30 healthy controls (HC) were included in the study. Sputum fluid concentrations of sBTLA, sCTLA-4 and sPD-1 were measured with ELISA. Comparisons were made with Mann-Whitney U test and correlations with IL-17, IL-26 levels and FEV1 (%) were assessed with Spearman’s Rank correlation test. Results: sBTLA levels were significantly higher in the severe and moderate asthmatic patients compared to healthy controls. Significant differences were observed between severe and moderate asthmatics (p < 0.0001). No significant differences were found between mild asthmatics and healthy controls (p = 0.799). Soluble PD-1 levels were higher in severe and moderate asthmatic patients compared to HC and no significant difference was observed between these two asthmatic groups (p = 0.124). Mild asthmatics and control subjects expressed similar sPD-1 levels (p = 0.856). Soluble CTLA-4 was exclusively expressed in certain severe asthmatic patients. IL-17 inflammatory cytokine was significantly correlated with BTLA and sPD-1. IL-17 and IL-26 cytokines were highly expressed in sputum asthmatic groups compared to sputum from HC. Severe asthmatic group was characterized by the highest levels of both IL-17 and IL-26 mediators. Soluble BTLA correlates positively with IL-17 (r = 0.817; p < 0.0001) and IL-26 (r = 0.805; p < 0.0001) inflammatory cytokines. IL-17 and IL-26 levels were associated with the asthma clinical severity from severe to mild asthma (p < 0.0001). The inflammatory cytokines IL-17 and IL-26 were positively correlated with the percentages of macrophages, PNN and FEV1 (%). Conclusion: Here, we provide the first report on the increased expression of sBTLA and sPD-1 in induced sputum of severe asthmatics. IL-26 and IL-17 appeared as a novel proinflammatory axis. Both sBTLA and sPD-1 might be involved in the pathogenesis of asthma and were associated with a poor prognosis

H,K-ATPase type 2 contributes to salt-sensitive hypertension induced by K+ restriction

In industrialized countries, a large part of the population is daily exposed to low K(+) intake, a situation correlated with the development of salt-sensitive hypertension. Among many processes, adaptation to K(+)-restriction involves the stimulation of H,K-ATPase type 2 (HKA2) in the kidney and colon and, in this study, we have investigated whether HKA2 also contributes to the determination of blood pressure (BP). By using wild-type (WT) and HKA2-null mice (HKA2 KO), we showed that after 4 days of K(+) restriction, WT remain normokalemic and normotensive (112 ± 3 mmHg) whereas HKA2 KO mice exhibit hypokalemia and hypotension (104 ± 2 mmHg). The decrease of BP in HKA2 KO is due to the absence of NaCl-cotransporter (NCC) stimulation, leading to renal loss of salt and decreased extracellular volume (by 20 %). These effects are likely related to the renal resistance to vasopressin observed in HKA2 KO that may be explained, in part by the increased production of prostaglandin E2 (PGE2). In WT, the stimulation of NCC induced by K(+)-restriction is responsible for the elevation in BP when salt intake increases, an effect blunted in HKA2-null mice. The presence of an activated HKA2 is therefore required to limit the decrease in plasma [K(+)] but also contributes to the development of salt-sensitive hypertension