Abstract-It has been recognized that the sympathetic nervous system is activated in pulmonary arterial hypertension (PAH), and abnormal sympathetic hyperactivity leads to worsening of PAH via endothelial dysfunction. The purpose of this study was to examine whether sympathetic ganglion block (SGB) can treat PAH by increasing the availability of nitric oxide (NO). PAH was induced in rats by 50 mg/kg of subcutaneous monocrotaline. After 2 weeks, daily injections of ropivacaine into the left superior cervical ganglion were repeated for 14 days (monocrotaline-SGB group). Monocrotaline group received sham SGB with saline, whereas control group received saline instead of monocrotaline. PAH was evident in monocrotaline group, with right ventricular systolic pressures (47±4 mm Hg) that were higher than those of controls (17±2 mm Hg), whereas SGB significantly attenuated monocrotalineinduced PAH (35±4 mm Hg). The right/left ventricular mass ratios exhibited similar changes to those seen with right ventricular pressures. Heart rate variability showed significantly higher sympathetic activity in the monocrotaline group. Microscopy revealed a higher proportion of muscular arteries with thicker medial walls in the monocrotaline group, which was attenuated by SGB. Monocrotaline induced arginase hyperactivity, which was in turn decreased by SGB-induced endothelial NO synthase activation. SGB restored monocrotaline-induced hypoactivity of superoxide dismutase. In conclusion, SGB could suppress PAH and the remodeling of pulmonary arteries via inactivation of arginase and reciprocal elevation of NO bioavailability, thus attenuating disproportionate hyperactivation of the have been reported to attenuate the severity of symptoms and slow the progression of cardiovascular diseases including coronary artery disease, heart failure, and arrhythmias. According to the previous reports, there is a possibility that direct sympathetic nerve blocks are effective in patients with myocardial ischemia or systemic hypertension. 17,19 Given the relationship between sympathetic nervous system hyperactivity and endothelial dysfunction in patients with PAH, blockade of sympathetic hyperactivity may improve vascular reactivity by preserving endothelial function. To date, however, there is limited amount of data on the therapeutic effects of sympathetic ganglion block (SGB) on PAH. The purpose of the present study is to assess the therapeutic effects of SGB in a monocrotaline-induced PAH rat model. In parallel, we investigated whether SGB could attenuate the changes in arginase and NO bioavailability, as well as oxidative stress caused by monocrotaline. MethodsDetailed methods about animal preparation, experimental design, SGB, heart rate variability, hemodynamic analysis, right ventricular mass, pulmonary vessel morphometry, and NO (synthase)/arginase/ cGMP/oxidative stress assay are described in the online-only Data Supplement. Results Right Ventricular Systolic Pressure and Right Ventricular/Left Ventricular Mass RatioRight ventricular systolic pr...
This study was done to examine the level of symptom experience, and symptom variation in relation to demographic and clinical variables, in Korean patients with liver cirrhosis (LC). Symptom experience was measured using a scale developed by the researchers through a literature review on LC. Participants were 129 patients whose mean age was 53.6 (standard deviation [SD] = 9.28) years. The results indicated that (1) overall symptom experience was relatively low (mean 41.67, SD 24.71); (2) the main symptoms needing a management were fatigue, abdominal distension and/or peripheral edema, and muscle cramps; and (3) among the study variables, the severity of LC (P < 0.001) and the number of hospitalizations (P = 0.014) showed a significant relationship with overall symptom experience. These results suggest that symptom assessment requires a multidimensional approach and that it is imperative to consider disease severity in developing tailored symptom management programs for Korean patients with LC.
Purpose: The purpose of this study was to construct and test a structural equation model on resilience of breast cancer patients receiving chemotherapy. Methods: Participants were 204 patients with breast cancer who received chemotherapy treatment. They participated in a structured interview, which included social support, depression, symptom experience, self-efficacy, hope, resilience, and infection prevention behaviors. Data were analyzed using SPSS/WIN 20.0 and AMOS 18.0. Results: Lower depression ( γ=-.33, p =.020) and symptom experience ( γ=-.31, p =.012) and higher self-efficacy ( γ=.32, p =.005) and hope ( γ=.48, p =.016) were influenced by higher social support. Greater resilience was influenced by lower symptom experience (β=-.18, p =.016), higher self-efficacy (β=.49, p =.023), and higher hope (β =.46, p =.012), and these predictors explained 66.7% of variance in resilience. Greater resilience (β=.54, p =.009) made an impact on greater infection prevention behaviors. Resilience mediated the relations of symptom experience (β=-.10 p =.013), self-efficacy (β=.27, p =.006) and hope (β=.25, p =.009) with infection prevention behaviors. These predictors explained 24.9% of variance in infection prevention behaviors. Conclusion: The findings of the study suggest that breast cancer patients with greater resilience who are receiving chemotherapy participate in increased infection prevention behaviors. Further research should be conducted to seek intervention strategies that improve breast cancer patients' resilience. If the original work is properly cited and retained without any modification or reproduction, it can be used and re-distributed in any format and medium.
PurposeOxidative stress during CO2 pneumoperitoneum is reported to be associated with decreased bioactivity of nitric oxide (NO). However, the changes in endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), and arginase during CO2 pneumoperitoneum have not been elucidated.Materials and MethodsThirty male Sprague-Dawley rats were randomized into three groups. After anesthesia induction, the abdominal cavities of the rats of groups intra-abdominal pressure (IAP)-10 and IAP-20 were insufflated with CO2 at pressures of 10 mm Hg and 20 mm Hg, respectively, for 2 hours. The rats of group IAP-0 were not insufflated. After deflation, plasma NO was measured, while protein expression levels and activity of eNOS, iNOS, arginase (Arg) I, and Arg II were analyzed with aorta and lung tissue samples.ResultsPlasma nitrite concentration and eNOS expression were significantly suppressed in groups IAP-10 and IAP-20 compared to IAP-0. While expression of iNOS and Arg I were comparable between the three groups, Arg II expression was significantly greater in group IAP-20 than in group IAP-0. Activity of eNOS was significantly lower in groups IAP-10 and IAP-20 than in group IAP-0, while iNOS activity was significantly greater in group IAP-20 than in groups IAP-0 and IAP-10. Arginase activity was significantly greater in group IAP-20 than in groups IAP-0 and IAP-10.ConclusionThe activity of eNOS decreases during CO2 pneumoperitoneum, while iNOS activity is significantly increased, a change that contributes to increased oxidative stress and inflammation. Moreover, arginase expression and activity is increased during CO2 pneumoperitoneum, which seems to act inversely to the NO system.
Abnormal degradation of matrix components due to dysregulated expression of matrix metalloproteinase (MMP)-9 in macrophages has been linked to progression of acute cerebral ischemia and atherosclerosis. We report that lithium chloride (LiCl) or CHIR99021, inhibitors of Wnt signaling pathway, enhance phosphorylation of glycogen synthase kinase-3beta and suppress lipopolysaccharide-mediated upregulation of MMP-9 expression in murine macrophage RAW264.7 cells in a dose-dependent manner. Suppression of MMP-9 expression by LiCl or CHIR99021 did not result after inhibition of kinases involved in NFκB or AP-1 family proteins, but from changes in the activity of histone deacetylases. Beneficial effects on atherosclerosis or cerebral ischemia in animal studies caused by LiCl may be in part explained by the suppression of MMP-9 gene expression.
BackgroundPneumoperitoneum-induced oxidative stress and organ injury are known to be associated with nitric oxide (NO) inactivation. Because arginase competes with NO synthase (NOS) for a common substrate, L-arginine, arginase inhibition may increase NO bioavailability. Therefore, we evaluated the ability of the arginase inhibitor, 2 (S)-amino-6-boronohexanoic acid (ABH), to attenuate pneumoperitoneum-induced decrease of NO bioavailability and lung injury.MethodsThirty rats were randomly divided into the following groups: 1) the PP-ABH group received a subcutaneous injection of ABH (5 mg/kg) 1 h before induction of pneumoperitoneum (insufflation to intraperitoneal pressure of 15 mmHg for 60 min); 2) the PP group received saline by subcutaneous injection 1 h before induction of pneumoperitoneum; and 3) the control group received saline by subcutaneous injection before a sham procedure with no gas insufflation. After desufflation, blood was collected to determine levels of plasma nitrite, NOS, inflammatory cytokines, and malondialdehyde, a marker of oxidative stress. Lung tissue was obtained for histological evaluation.ResultsWe found that plasma nitrite levels were lower in the PP group and higher in the PP-ABH group, compared with controls (P <0.01 and P <0.05, respectively). In the PP group, endothelial NOS activity was decreased and inducible NOS activity was increased compared with the PP-ABH and control groups. Malondialdehyde levels increased 3-fold in the PP group and 2-fold in the PP-ABH group compared with controls. Tumor necrosis factor-α, interleukin-6, and interleukin-1ß levels were elevated in the PP group compared to the control group, but the increase in cytokine production was attenuated or blocked in the PP-ABH group. Lung injury scores were 4.8-fold higher in the PP group and 2-fold higher in the PP-ABH group compared with controls (P <0.001 and P <0.01, respectively).DiscussionPneumoperitoneum decreases NO bioavailability and increases the inflammation cytokines, resulting in organ injuries. Inhibition of arginase activity could maintain NO bioavailability by attenuating pneumoperitoneum-induced changes in NOS activity. In addition, arginase inhibition attenuated the oxidative stress and inflammation and decreased the severity of lung injury caused by pneumoperitoneum.ConclusionsBy increasing NO bioavailability and suppressing oxidative stress and inflammation, pretreatment with an arginase inhibitor may protect against lung injury caused by pneumoperitoneum.
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