This study was designed to assess the changes in nonlinear properties of heart rate (HR) variability (HRV) during the menstrual cycle by means of complexity measures, including sample entropy (SampEn) and correlation dimension (CD), and explore probable physiological interpretations for them. In 16 healthy women (mean age: 23.8 +/- 2.7 yr), complexity measures along with the spectral components of HRV (sympathovagal markers) were analyzed over 1,500 R-R intervals recorded during both the follicular phase (day 11.9 +/- 1.4) and the luteal phase (day 22.0 +/- 1.4) of each woman's menstrual cycle. Simultaneously, serum ovarian hormone (estradiol-17 and progesterone) and thyroid-related hormone [free triiodothyronine, free thyroxine (T(4)), and thyroid-stimulating hormone] concentrations were measured. With regard to HRV measures, SampEn, CD, and high-frequency (HF) components decreased from the follicular phase to the luteal phase, whereas normalized low-frequency (LF) components and the LF-to-HF ratio as well as resting HR increased. In regard to hormone levels, whereas progesterone was increased, the other hormone concentrations were unchanged. Furthermore, across the menstrual cycle, both SampEn and CD were well correlated with the spectral indexes and free T(4) concentrations, and SampEn also showed significant correlations with the ratio of estradiol-17 to progesterone concentrations. These results suggest that the nonlinear properties in HRV are altered during the regular menstrual cycle and that the autonomic nervous system, ovarian hormone balance, and free T(4) may be involved in nonlinear HR control in healthy women. All of these factors may enrich the physiological meanings of complexity measures.
The present study was designed to investigate whether arsenic trioxide induced the apoptosis in rat mesenteric arterial smooth muscle cells (SMCs), which provides new insights into mechanisms of arsenic-related vascular diseases. Here, we found that arsenic trioxide significantly decreased the viability of SMCs in a dose-dependent manner. In addition, higher level of arsenic trioxide directly caused cellular necrosis. The Hoechst and AO/EB staining demonstrated that apoptotic morphological change was presented in SMCs exposed to arsenic trioxide. The TUNEL assay displayed that more positive apoptotic signal appeared in SMCs treated with arsenic trioxide. The following result showed that ROS formation was markedly increased in arsenic trioxide-treated SMCs. Pretreatment with N-acetylcysteine, an anti-oxidant reagent, obviously attenuated the enhancement of ROS production and the reduction of cell viability induced by arsenic trioxide in SMCs. Arsenic trioxide also enhanced free intracellular Ca(2+) level in SMCs. BAPTA also significantly prevented the increased intracellular Ca(2+) and decreased cell viability induced by arsenic trioxide in SMCs. These results suggested that arsenic trioxide obviously induced apoptosis in SMCs, and its mechanism was partially associated with intracellular ROS formation and free Ca(2+) increasing.
Resveratrol increases endothelial NO production to improve endothelial dysfunction and lowers BP in hypertensive rats, which depends on calcium-eNOS activation.
It is acknowledged that contrast-induced nephropathy (CIN) is a common cause of acute renal insufficiency after cardiac catheterization and affects mortality and morbidity. To date, it is unknown whether oral N-acetylcysteine (NAC) is able to prevent contrast-induced nephropathy (CIN) in patients undergoing coronary angioplasty. A meta-analysis of randomized controlled trials was performed to assess the effects of NAC in the prevention of CIN in patients following coronary angioplasty. A total of 19 studies published prior to January 2015 that investigated the efficacy of oral NAC for the prevention of CIN were collected from Medline, Cochrane and Embase databases and conference proceedings from cardiology and nephrology meetings. The primary point of investigation was CIN, and the secondary points were renal failure requiring dialysis, mortality and length of hospitalization. The meta-analysis was performed using fixed- or random-effect models according to heterogeneity. Up to January 2015, 19 randomized placebo-controlled clinical trials met the inclusion criteria for the meta-analysis, including 4,514 patients. The pooled data showed that oral NAC did not reduce the CIN incidence [relative risk 0.84, 95% confidence interval (CI) 0.65–1.10; P=0.20], without heterogeneity among trials (I2=29%). Thus, the present meta-analysis suggests that oral NAC therapy is not effective as an alternative treatment to prevent CIN in patients following angioplasty. Further high quality randomized clinical controlled trials are required to confirm the usage and availability of this treatment.
This case report describes the electrocardiogram findings of a patient in their 30s who attempted suicide by taking propafenone and presented to the emergency department with impaired consciousness and convulsions.
Objectives: We sought to determine whether high posttreatment platelet reactivity (HPPR) to a 600 mg loading dose of clopidogrel affects outcomes in Chinese patients with acute coronary syndrome (ACS) following percutaneous coronary intervention (PCI) and to investigate whether there is a relationship between the number of platelet reactivityunits (PRUs) and the characteristics of the patients.Background: Although impaired platelet response to clopidogrel is a strong predictor of unfavorable outcome after PCI, the impact of HPPR to a 600 mg loading dose of clopidogrel in Chinese patients with ACS undergoing PCI is still unknown.Methods: We performed observational research on 134 unselected patients with ACS undergoing urgent or planned PCI with a 600 mg loading dose of clopidogrel. Platelet activation was expressed as the PRU value measured by the VerifyNow assay.Results: Among the 134 patients (mean age 60.62 years [standard deviation 9.13 years], 60.4% male), there were 46patients with HPPR (34.3%) and 88 patients without HPPR (65.7%). At a mean follow-up of 6 months (standard deviation 1 month), the rates of cardiac death, unstable angina, and rehospitalization for target lesion revascularization werehigher in the HPPR group (19.6% vs. 6.8%, P = 0.029). Multivariate analysis identified hemoglobin level and sex as independent predictors of the PRU value (y = 456.355 − 1.736x1 − 31.880x2, P < 0.05). On receiver operating characteristiccurve analysis, PRU values could significantly discriminate between patients with and patients without cardiac death,unstable angina, and rehospitalization for target lesion revascularization (area under the curve 0.758, 95% confidenceinterval 0.62–0.85, P = 0.001, P < 0.05).Conclusion: In patients with ACS, HPPR to a 600 mg loading dose of clopidogrel is associated with worse outcomes after PCI. There is some relationship between the PRU value and the hemoglobin level and sex. PRU values can predict the prognosis.
A challenge for antithrombotic treatment is patients who present with atrial fibrillation (AF) and acute coronary syndrome, particularly in patients who have undergone coronary percutaneous intervention with stenting (PCIS). In the present study, a total of nine observational trials published prior to July 2017 that investigated the effects of dual antiplatelet therapy (DAPT; aspirin + clopidogrel) and triple oral antithrombotic therapy (TOAT; DAPT + warfarin) among patients with AF concurrent to PCIS were collected from the Medline, Cochrane and Embase databases and conference proceedings of cardiology, gastroenterology and neurology meetings. A meta-analysis was performed using fixed- or random-effect models according to heterogeneity. The subgroups were also analyzed on the occurrence of major adverse cardiac events (MACE), stroke and bleeding events in the two treatment groups. Analysis of baseline characteristics indicated that there was no significant difference in the history of coexistent disease or conventional therapies between the DAPT and TOAT groups. The primary end point incidence was 2,588 patients in the DAPT group (n=13,773) and 871 patients in the TOAT group (n=5,262) following pooling of all nine trials. There was no statistically significant difference in the incidence of primary end points between the DAPT and TOAT groups. Odds ratio (OR)=0.96, 95% confidence interval (CI)=0.73–1.27, P=0.79, with heterogeneity between trials (I2=82%, P<0.00001). Subsequently, on subgroup analysis, the results indicated no increased risk of major bleeding or ischemic stroke in the DAPT or TOAT group. However, compared with the TOAT group, there was an apparent increased risk of MACE plus ischemic stroke in the DAPT group (OR=1.62, 95% CI=1.43–1.83, P<0.00001) with heterogeneity between trials (I2=70%, P=0.01). In conclusion, the present meta-analysis suggests that TOAT (aspirin + clopidogrel + warfarin) therapy for patients with AF concurrent to PCIS significantly reduced the risk of MACE and stroke compared with DAPT (aspirin + clopidogrel) therapy. Further randomized controlled clinical trials are required to confirm the efficacy of the optimal antithrombotic therapy in patients with AF following PCIS.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.