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Shift work and artificial light at night disrupt the entrainment of endogenous circadian rhythms in physiology and behavior to the day-night cycle. We hypothesized that exposure to dim light at night (dLAN) disrupts feeding rhythms, leading to sex-specific changes in autonomic signaling and day-night heart rate and blood pressure rhythms. Compared to mice housed in 12-hour light/12-hour dark cycles, mice exposed to dLAN showed reduced amplitudes in day-night feeding, heart rate, and blood pressure rhythms. In female mice, dLAN reduced the amplitude of day-night cardiovascular rhythms by decreasing the relative sympathetic regulation at night, while in male mice, it did so by increasing the relative sympathetic regulation during the daytime. Time-restricted feeding to the dim light cycle reversed these autonomic changes in both sexes. We conclude that dLAN induces sex-specific changes in autonomic regulation of heart rate and blood pressure, and time-restricted feeding may represent a chronotherapeutic strategy to mitigate the cardiovascular impact of light at night., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Graphene, when electrified, generates far-infrared radiation within the wavelength range of 4 μm to 14 μm. This range closely aligns with the far-infrared band (3 μm to 15 μm), which produces unique physiological effects. Contraction and relaxation of vascular smooth muscle play a significant role in primary hypertension, involving the nitric oxide-soluble guanylate cyclase-cyclic guanosine monophosphate pathway and the renin-angiotensin-aldosterone system. This study utilized spontaneously hypertensive rats (SHRs) as an untr-HT to investigate the impact of far-infrared radiation at specific wavelengths generated by electrified graphene on vascular smooth muscle and blood pressure. After 7 weeks, the blood pressure of the untr-HT group rats decreased significantly with a notable reduction in the number of vascular wall cells and the thickness of the vascular wall, as well as a decreased ratio of vessel wall thickness to lumen diameter. Additionally, blood flow perfusion significantly increased, and the expression of F-actin in vascular smooth muscle myosin decreased significantly. Serum levels of angiotensin II (Ang-II) and endothelin 1 (ET-1) were significantly reduced, while nitric oxide synthase (eNOS) expression increased significantly. At the protein level, eNOS expression decreased significantly, while α-SMA expression increased significantly in aortic tissue. At the gene level, expressions of eNOS and α-SMA in aortic tissue significantly increased. Furthermore, the content of nitric oxide (NO) in the SHR's aortic tissue increased significantly. These findings confirm that graphene far-infrared radiation enhances microcirculation, regulates cytokines affecting vascular smooth muscle contraction, and modifies vascular morphology and smooth muscle phenotype, offering relief for primary hypertension.

Background: Hyperthyroid cats commonly have systemic hypertension, with a reported prevalence of 7% to 48%. Although hypertension might be expected to resolve once treatment restores euthyroidism, it can persist or only first develop after treatment., Objectives: To determine the proportion of hyperthyroid cats with hypertension (systolic blood pressure [SBP] ≥160 mm Hg), persistence or first development of hypertension after successful radioiodine treatment, and correlation of post-treatment hypertension with azotemia or hypothyroidism., Animals: Four hundred one hyperthyroid nonazotemic cats were included in the study., Methods: Prospective, cross-sectional and before-and-after studies. All hyperthyroid cats had SBP measured by Doppler; 255 had SBP rechecked 6 months after successful radioiodine ( 131 I) treatment., Results: Of untreated hyperthyroid cats, 108/401 (27%) were hypertensive. A higher proportion of hypertensive cats were nervous/excited compared with normotensive cats (47% vs 12%; P < .001). Of the initially hypertensive cats, 87/108 cats were reexamined after 131 I treatment; 43/87 (49%) cats normalized SBP, whereas 44/87 (51%) remained hypertensive. Of the initially normotensive cats, 16/168 (9.5%) first developed hypertension after successful 131 I treatment. 7/60 (12%) of the 131 I-treated hypertensive cats were azotemic and 9/60 (15%) were hypothyroid. A higher proportion of cats remaining hypertensive had nervous/excited demeanor than did normotensive cats (50% vs 17%; P < .001)., Conclusions/clinical Importance: Hypertension, when present, resolves in many hyperthyroid cats after successful treatment. Hyperthyroid cats uncommonly develop new hypertension after treatment. Persistent or newly detected hypertension was unrelated to azotemia or iatrogenic hypothyroidism. More frequently perceived nervousness/anxiety in radioiodine-treated hypertensive cats suggests that many of these cats might have "situational" hypertension, as hyperthyroid-induced hypertension should resolve after treatment., (© 2024 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Objective: To assess the impact of intravascular laser irradiation of blood (ILIB) on the primitive carotid artery (PCA) hemodynamic variables, specifically blood pressure (BP) and heart rate (HR), in mastectomized patients undergoing hormone blocker treatments. Materials and methods: This study is a controlled, experimental, and randomized clinical trial. Patients were allocated into two groups: the experimental group (G1)-patients who received ILIB therapy using a 660 nm laser targeted at the PCA, and the control group (G2)-patients who did not receive ILIB therapy. Clinical research was conducted weekly, with measurements of systolic blood pressure (SBP), diastolic blood pressure (DBP), and HR. The Mann-Whitney U test for independent samples was used, with a significance level of α = 0.05. Results: Systemic photobiomodulation on the PCA did not demonstrate a statistically significant difference in relation to SBP and DBP. However, for HR, the p -value was <0.05, indicating a significant difference between G1 and G2. The initial mean p > decreased from 142.3 to 116.4 mmHg in G1, and from 130.4 to 119.8 mmHg in G2. The DBP varied from 78.8 to 72.8 mmHg in G1, and from 79.1 to 74.2 mmHg in G2. A statistically significant difference was observed in HR, decreasing from 81.3 to 62.06 bpm in G1, and changing minimally from 74.1 to 75.1 bpm in G2. A considerable reduction was present in the timing of application. Conclusions: ILIB therapy applied to the PCA induces a reduction in BP and, more notably, HR in mastectomized women using the tamoxifen or aromatase inhibitors.

Injury of the afferent limb of the baroreflex from neck radiation causes radiation-induced afferent baroreflex failure (R-ABF). Identification and management of R-ABF is challenging. We aimed to investigate the pattern of autonomic dysfunction on standardized autonomic testing in patients with probable R-ABF. We retrospectively analyzed all autonomic reflex screens performed at Mayo Clinic in Rochester, MN, between 2000 and 2020 in patients with probable R-ABF. Additional tests reviewed included ambulatory blood pressure monitoring, plasma norepinephrine, and thermoregulatory sweat test. We identified 90 patients with probable R-ABF. Median total composite autonomic severity score (range, 0-10) was 7 (interquartile range, 6-7). Cardiovascular adrenergic impairment was seen in 85 patients (94.4%), increased blood pressure recovery time after Valsalva maneuver in 71 patients (78.9%; median 17.4 seconds), and orthostatic hypotension in 68 patients (75.6%). Cardiovagal impairment was demonstrated by abnormal heart rate responses to deep breathing (79.5%), Valsalva ratio (87.2%), and vagal baroreflex sensitivity (57.9%). Plasma norepinephrine was elevated and rose appropriately upon standing (722-1207 pg/mL). Ambulatory blood pressure monitoring revealed hypertension, postural hypotension, hypertensive surges, tachycardia, and absence of nocturnal dipping. Blood pressure lability correlated with impaired vagal baroreflex function. Postganglionic sympathetic sudomotor function was normal in most cases; the most frequent thermoregulatory sweat test finding was focal neck anhidrosis (78.9%). Standardized autonomic testing in R-ABF demonstrates cardiovascular adrenergic impairment with orthostatic hypotension, blood pressure lability, and elevated plasma norepinephrine. Cardiovagal impairment is common, while sudomotor deficits are limited to direct radiation effects.

The aim of the present study was to analyze the effect of neuromuscular electrical stimulation (NMES) and photobiomodulation (PBMT) on the cardiovascular parameters, hemodynamic function, arterial baroreflex sensitivity (BRS), and autonomic balance (ANS) of rats with heart failure (HF). Male Wistar rats (220-290 g) were organized into five groups: Sham ( n = 6), Control-HF ( n = 5), NMES-HF ( n = 6), PBMT-HF ( n = 6), and NMES + PBMT-HF ( n = 6). Myocardial infarction (MI) was induced by left coronary artery ligation. Animals were subjected to an eight-week NMES and PBMT protocol. Statistical analysis included the General Linear Model (GLM) followed by a Bonferroni post-hoc test. Rats of the NMES-HF group showed a higher MI area than the Control-HF ( P = 0.003), PBMT-HF ( P = 0.002), and NMES + PBMT-HF ( P = 0.012) groups. NMES-HF and NMES + PBMT-HF showed higher pulmonary congestion ( P = 0.004 and P = 0.02) and lower systolic pressure ( P = 0.019 and P = 0.002) than the Sham group. NMES + PBMT-HF showed lower mean arterial pressure ( P = 0.02) than the Sham group. Control-HF showed a higher heart rate than the NMES-HF and NMES + PBMT-HF ( P = 0.017 and P = 0.013) groups. There was no difference in the BRS and ANS variables between groups. In conclusion, eight-week NMES isolated or associated with PBMT protocol reduced basal heart rate, systolic and mean arterial pressure, without influence on baroreflex sensibility and autonomic control, and no effect of PBMT was seen in rats with HF.

This study investigated the effect of 448 kHz capacitive resistive monopolar radiofrequency (CRMRF) on the superficial and deep physiological responses of patients with osteoarthritis (OA) of the knee(s). Forty-five patients diagnosed with OA in their knee(s) were enrolled into a three-group randomised controlled study, from the waiting list of a local hospital. They received localized treatment with either CRMRF, CRMRF placebo or a control (no treatment) to the knee for 15 minutes. Pre, post, and 20 min follow-up measurements of skin temperature (SKT) and skin blood flow (SBF) were obtained from the knee using the FlexComp Infiniti (SA7550) physiological measurement system. Pre and post-treatment deep blood flow were recorded using Doppler ultrasound. Core temperature, blood pressure (BP) and pulse rate (PR) were concurrently monitored. Group data were compared using the ANOVA model. Statistical significance was set at p ≤ 0.05, 0.8 power, and 95% CI. Significant increases and sustenance of SKT and SBF, and significant increases in volume and intensity of deep blood flow were demonstrated with CRMRF over the placebo and control interventions in all comparisons ( p < .001). No meaningful changes in blood flow velocity, core temperature, BP, or PR were noted for any condition. The findings were markedly more pronounced than those previously reported in asymptomatic adults. However, the patients had received a higher average dose of CRMRF (mean (SD): 46.87 (4.08) W) compared to the asymptomatic sample (mean (SD): 42.37 (4.64) W); therefore, further research is needed to better understand the differences in physiological responses between patients and asymptomatic people.

Purpose: The effects of radioactivity on human health have been debated for many years but there are still important gaps that need to be addressed especially related to the effects of high natural background radiation on the local population. The beach of Meaípe, in the city of Guarapari (Brazil), emits natural gamma radiation due to the presence of monazite sands. We aimed to investigate the effects of gamma radiation doses on the biological system of wistar rats using a physical simulator of gamma radiation designed using Meaípe monazite sands., Methods: Female Wistar rats were divided into three groups, submitted to no radiation (control group) and to continuous radiation levels, one of very high level (20 μSv h -1 ) and another of high level (3.6 μSv h -1 ). The three group of animals were monitored weekly for 3 months and at the end of the study the animals were sacrificed, and the organs were extracted and weighed for anthropometric, oxidative stress and histological evaluations., Results: Exposure to radiation released by the monazite sands did not cause anthropometric alterations or blood pressure change in the animals. Similarly, there was no change in the quantification of ovarian follicles between the radiation groups and the control group. There was no difference in the oxidative stress quantification by the thiobarbituric acid reactive substance and advanced oxidation protein product methods in the ovaries. There were no evidenced damages in the structure of the renal tissue. It was observed the presence of granulomas in the hepatic tissue and alterations in the nuclei of the hepatocytes., Conclusions: Our results suggest that the continuous exposure of females rats to 3.6 and 20 μSv h -1 doses of gamma radiation slightly affected the hepatic tissue, but did not alter the histological parameters in the kidneys and ovaries and oxidative stress.

In this work, we utilized spontaneously hypertensive rats (SHR) and Wister Kyoto rats (WKY), from which the SHR was established, to evaluate the effects of whole-body acute radiation on the cardiovascular system at doses from 0 to 4 Gy. In the irradiated SHR, the systolic blood pressure (SBP) increased with increasing dose, while body weight gain decreased with increasing radiation dose. Furthermore, pathological observations of SHR demonstrated that the number of rats with cystic degeneration in the liver increased with increasing dose. The effects observed among SHR, such as increased SBP and retardation of body weight gain, appear very similar to those observed in Japanese atomic bomb survivors. In contrast, the SBP among WKY did not change relative to dose; the body weight, however, did change, as in the SHR. Therefore, the association between radiation exposure and SBP, but not between radiation exposure and retardation of body weight gain, may be affected by genetic background, as evident from strain difference. These results suggest that the SHR and WKY animal models may be useful for studying radiation effects on non-cancer diseases including circulatory diseases, chronic liver disease and developmental retardation., (©2020 by Radiation Research Society. All rights of reproduction in any form reserved.)

To evaluate whether acute photobiomodulation can elicit a hypotensive effect in spontaneously hypertensive rats (SHR). Male SHR were submitted to the implantation of a polyethylene cannula into the femoral artery. After 24 h, baseline measurements of the hemodynamic parameters: systolic, diastolic, and mean arterial pressure, and heart rate were accomplished for 1 h. Afterwards, laser application was simulated, and the hemodynamic parameters were recorded for 1 h. In the same animal, the laser was applied at six different positions of the rat's abdomen, and the hemodynamic parameters were also recorded until the end of the hypotensive effect. The irradiation parameters were red wavelength (660 nm); average optical power of 100 mW; 56 s per point (six points); spot area of 0.0586 cm 2 ; and irradiance of 1.71 W/cm 2 yielding to a fluency of 96 J/cm 2 per point. For measuring plasma NO levels, blood was collected before the recording, as well as immediately after the end of the mediated hypotensive effect. Photobiomodulation therapy was able to reduce the systolic arterial pressure in 69% of the SHR submitted to the application, displaying a decrease in systolic, diastolic, and mean arterial pressure. No change in heart rate was observed. Nevertheless, there was an increase in serum nitric oxide levels in the SHR responsive to photobiomodulation. Our results suggest that acute irradiation with a red laser at 660 nm can elicit a hypotensive effect in SHR, probably by a mechanism involving the release of NO, without changing the heart rate.

Background Hypertension remains a leading global cause for premature death and disease. Most treatment guidelines emphasize the importance of risk factors, but not all are known, modifiable, or easily avoided. Population blood pressure correlates with latitude and is lower in summer than winter. Seasonal variations in sunlight exposure account for these differences, with temperature believed to be the main contributor. Recent research indicates that UV light enhances nitric oxide availability by mobilizing storage forms in the skin, suggesting incident solar UV radiation may lower blood pressure. We tested this hypothesis by exploring the association between environmental UV exposure and systolic blood pressure (SBP) in a large cohort of chronic hemodialysis patients in whom SBP is determined regularly. Methods and Results We studied 342 457 patients (36% black, 64% white) at 2178 US dialysis centers over 3 years. Incident UV radiation and temperature data for each clinic location were retrieved from the National Oceanic and Atmospheric Administration database. Linear mixed effects models with adjustment for ambient temperature, sex/age, body mass index, serum Na + /K + and other covariates were fitted to each location and combined estimates of associations calculated using the DerSimonian and Laird procedure. Pre-dialysis SBP varied by season and was ≈4 mm Hg higher in black patients. Temperature, UVA and UVB were all linearly and inversely associated with SBP. This relationship remained statistically significant after correcting for temperature. Conclusions In hemodialysis patients, in addition to environmental temperature, incident solar UV radiation is associated with lower SBP. This raises the possibility that insufficient sunlight is a new risk factor for hypertension, perhaps even in the general population.

: A 64-year-old man, whose medical history was significant only for locally advanced squamocellular carcinoma of the right palatine tonsil treated with extended neck radiotherapy 9 years before, was evaluated for traumatic cerebral haemorrhage secondary to syncope after a postural change. The selective angiographic study of cerebral vessels was negative. No heart arrhythmias were recorded at ECG monitoring. The 24-h ABPM revealed sudden pressor and depressor episodes during day-time and a reverse dipper pattern during night-time. Noninvasive autonomic nervous system function testing showed supine hypertension and orthostatic hypotension caused by afferent baroreflex failure. According to literature, even if only few cases are described, neck irradiation can be assumed to be the major cause of baroreflex failure. No treatment is currently approved. The patient was treated with a selective beta-blocker (bisoprolol) administered at bedtime. Repeated ABPM after 1 month of therapy showed absence of sudden pressor and depressor episodes and no dipper pattern during night-time.

Circadian rhythms are an inherent property of physiological processes and can be disturbed by irregular environmental cycles, including artificial light at night (ALAN). Circadian disruption may contribute to many pathologies, such as hypertension, obesity, and type 2 diabetes, but the underlying mechanisms are not understood. Our study investigated the consequences of ALAN on cardiovascular and metabolic parameters in spontaneously hypertensive rats, which represent an animal model of essential hypertension and insulin resistance. Adult males were exposed to a 12 h light - 12 h dark cycle and the ALAN group experienced dim light at night (1-2 lx), either for 2 or 5 weeks. Rats on ALAN showed a loss of light-dark variability for systolic blood pressure, but not for heart rate. Moreover, a gradual increase of systolic blood pressure was recorded over 5 weeks of ALAN. Exposure to ALAN increased plasma insulin and hepatic triglyceride levels. An increased expression of metabolic transcription factors, Pparα and Pparγ , in the epididymal fat and a decreased expression of Glut4 in the heart was found in the ALAN group. Our results demonstrate that low-intensity ALAN can disturb blood pressure control and augment insulin resistance in spontaneously hypertensive rats, and may represent a serious risk factor for cardiometabolic diseases.

Purpose: Developmental programming involves an adverse intrauterine environment which can result in offspring phenotype changes following birth. The developmental programming of hypertension has been reported to possibly involve oxidative stress at the cellular level. Ionizing radiation produces oxidative stress, even at low doses, and irradiation of animals is often coupled with potential sources of maternal stress such as transportation of animals or repeated handling. Materials and methods: Pregnant C57Bl/6J mice were irradiated on gestational day 15 with 5-1000 mGy 137 Cs gamma radiation. Post-natal weight, blood pressure (BP) and heart rate (HR) were measured. Radiation had minimal effects at doses ≤300 mGy, but 1000 mGy caused a significant reduction in HR in male pups and growth reduction at 16 weeks of age in both genders. The sham-irradiation protocol included repeated transportation in order to acclimate animals to transport. However, it may have resulted in programming, as sham-irradiation alone resulted in elevated BP measures compared to the offspring of animals that were never transported. Results and conclusions: Overall, there were minimal effects on cardiovascular measures or offspring weight due to irradiation except at 1000 mGy. The presence of maternal stress, a known trigger of developmental programming, may have confounded any potential irradiation effects.

The study was aimed to assess hypertension incidence risk in a cohort of workers occupationally exposed to ionizing radiation. The cohort included workers of Russian Mayak nuclear enterprise who were employed in 1948 to 1982 and followed up until December 31, 2013 (22 377 workers). All workers were occupationally exposed to external γ-rays and some (76.03%) also to α-particles from internally deposited plutonium. Mean cumulative absorbed liver doses from external γ-rays (mean±SD) were 0.45±0.65 Gy in male and 0.37±0.56 Gy in female, whereas doses from internal α-particles were 0.23±0.65 and 0.44±1.93 Gy in males and females, respectively. An excess relative risk per unit dose was calculated based on Poisson regression analysis and was described as linear and nonlinear trends with radiation dose including adjustments for nonradiation factors via stratifications. As of the end of the follow-up period, 8425 hypertension cases (38% of workers) were verified in the cohort (5745 cases in males [36%] and 2680 cases in females [49%]). Hypertension incidence was found to be significantly linearly associated with cumulative liver absorbed dose from external γ-rays: excess relative risk/Gy=0.14 (95% CI, 0.09-0.20). No significant association of hypertension incidence with cumulative liver absorbed dose from internal α-particles was found: excess relative risk/Gy=-0.01 (95% CI, non-available-0.05). Hypertension incidence risk in the study cohort was higher than that in the Japanese cohort of atomic bomb survivors (AHS [Adult Health Study]) but lower than a corresponding estimate for Chernobyl clean-up workers.

There is now strong evidence that radiofrequency electromagnetic field (RF-EMF) exposure influences the human electroencephalogram (EEG). While effects on the alpha band of the resting EEG have been repeatedly shown, the mechanisms underlying that effect have not been established. The current study used well-controlled methods to assess the RF-EMF exposure effect on the EEG and determine whether that effect might be thermally mediated. Thirty-six healthy adults participated in a randomized, double-blind, counterbalanced provocation study. A water-perfusion suit (34 C) was worn throughout the study to negate environmental influences and stabilize skin temperature. Participants attended the laboratory on four occasions, the first being a calibration session and the three subsequent ones being exposure sessions. During each exposure session, EEG and skin temperature (8 sites) were recorded continuously during a baseline phase, and then during a 30 min exposure to a 920 MHz GSM-like signal (Sham, Low RF-EMF (1 W/kg) and High RF-EMF (2 W/kg)). Consistent with previous research, alpha EEG activity increased during the High exposure condition compared to the Sham condition. As a measure of thermoregulatory activation, finger temperature was found to be higher during both exposure conditions compared to the Sham condition, indicating for the first time that the effect on the EEG is accompanied by thermoregulatory changes and suggesting that the effect of RF-EMF on the EEG is consistent with a thermal mechanism., Competing Interests: The authors declare no conflict of interest.

Purpose: Many studies are focusing on the biological effects of gamma irradiation at low-dose rates. Studies have shown that chronic exposure to gamma irradiation at low-dose rates shortened the lifespan of mice due to neoplasm formation. The aim of this study was to clarify the physiological effects of long-term exposure to gamma irradiation at low-dose rates in mice, measured with noninvasive parameters such as blood pressure., Materials and Methods: Specific-pathogen-free female B6C3F 1 mice were irradiated with gamma rays at a low dose of 20 mGy/day - a dose rate shown to shorten the life span in previous studies. The blood pressure parameters (systolic, diastolic, and mean blood pressure), heart rate, tail blood volume, and blood flow of the mice were measured every 7 weeks. Age-matched, non-irradiated mice were used as controls., Results and Conclusion: The blood pressure levels of the irradiated mice decreased at an earlier age compared to the non-irradiated control mice. The expression levels of the marker genes of aging that are also associated with regulation of blood pressure showed significant differences between non-irradiated and irradiated mice. These results indicated that long-term exposure to gamma irradiation at low-dose rates induce the expression levels of Rap1a and reduces Panx1 and Sirt3, which may have contributed to the accelerated blood pressure decline in female mice.

Background: Previous studies showed that radiofrequency energy delivery of the renal artery could induce an immediate and substantial blood pressure (BP)-elevation response, which might be indicative of the increase in central sympathetic nervous activity., Objective: The current study was to investigate whether the presence of BP-elevation response to radiofrequency energy delivery can serve as a surrogate to predict BP reduction following renal artery sympathetic denervation (RDN)., Method: Data were collected on 67 patients undergoing RDN for drug-resistant hypertension. The BP-elevation response to radiofrequency application was defined as elevation of SBP by at least 10 mmHg during radiofrequency energy delivery. The extent of BP reduction at 1, 3, 6, 12 months after RDN were analyzed. Multivariable linear regression analysis of baseline and procedural characteristics was performed to identify the determinants of BP reduction after RDN., Results: Ten patients (14.9%) were classified as nonresponders to radiofrequency delivery and showed significantly lower BP reduction compared with responders. The SBP reductions of radiofrequency delivery responders vs. nonresponders were 31.2 ± 8.6 vs. 11.4 ± 8.6 mmHg, 36.3 ± 10.0 vs. 14.6 ± 10.6 mmHg, 39.9 ± 9.9 vs. 15.2 ± 8.8 mmHg, and 40.0 ± 8.7/13.5 ± 5.8 mmHg (P < 0.001 for all) at 1, 3, 6, and 12 months, respectively. On multiple linear regression analysis, higher baseline office SBP, the presence of BP-elevation response to radiofrequency energy delivery, and especially larger number of BP-elevation response points, were independent predictors of SBP reduction at 6-month and 12-month follow-up., Conclusion: Baseline SBP and BP-elevation response during radiofrequency ablation, as well as larger positive response points to radiofrequency energy delivery could be an effective intraprocedural predictive markers to long-term procedural success of RDN.

Aims: Previous studies have shown that ultraviolet light can lead to the release of nitric oxide from the skin and decrease blood pressure. In contrast to visible light the local application of ultraviolet light bears a cancerogenic risk. Here, we investigated whether whole body exposure to visible blue light can also decrease blood pressure and increase endothelial function in healthy subjects., Methods: In a randomised crossover study, 14 healthy male subjects were exposed on 2 days to monochromatic blue light or blue light with a filter foil (control light) over 30 minutes. We measured blood pressure (primary endpoint), heart rate, forearm vascular resistance, forearm blood flow, endothelial function (flow-mediated dilation), pulse wave velocity and plasma nitric oxide species, nitrite and nitroso compounds (secondary endpoints) during and up to 2 hours after exposure., Results: Blue light exposure significantly decreased systolic blood pressure and increased heart rate as compared to control. In parallel, blue light significantly increased forearm blood flow, flow-mediated dilation, circulating nitric oxide species and nitroso compounds while it decreased forearm vascular resistance and pulse wave velocity., Conclusion: Whole body irradiation with visible blue light at real world doses improves blood pressure, endothelial function and arterial stiffness by nitric oxide released from photolabile intracutanous nitric oxide metabolites into circulating blood.

Severe lung damage is a major cause of death in blast victims, but the mechanisms of pulmonary blast injury are not well understood. Therefore, it is important to study the injury mechanism of pulmonary blast injury. A model of lung injury induced by blast exposure was established by using a simulation blast device. The effectiveness and reproducibility of the device were investigated. Eighty mice were randomly divided into eight groups: control group and 3 h, 6 h, 12 h, 24 h, 48 h, 7 days and 14 days post blast. The explosive device induced an explosion injury model of a single lung injury in mice. The success rate of the model was as high as 90%, and the degree of lung injury was basically the same under the same pressure. Under the same conditions, the thickness of the aluminum film can be from 0.8 mm to 1.6 mm, and the peak pressure could be from 95.85 ± 15.61 PSI to 423.32 ± 11.64 PSI. There is no statistical difference in intragroup comparison. A follow-up lung injury experiment using an aluminum film thickness of 1.4 mm showed a pressure of 337.46 ± 18.30 PSI induced a mortality rate of approximately 23.2%. Compared with the control group (372 ± 23 times/min, 85.9 ± 9.4 mmHg, 4.34 ± 0.09), blast exposed mice had decreased heart rate (283 ± 21 times/min) and blood pressure (73.6 ± 3.6 mmHg), and increased lung wet/dry weight ratio(2.67 ± 0.11), marked edematous lung tissue, ruptured blood vessels, infiltrating inflammatory cells, increased NF-κB (4.13 ± 0.01), TNF-α (4.13 ± 0.01), IL-1β (2.43 ± 0.01) and IL-6 (4.65 ± 0.01) mRNA and protein, decreased IL-10(0.18 ± 0.02) mRNA and protein ( P < 0.05). The formation of ROS and the expression of MDA5 (4.46 ± 0.01) and IREα (3.43 ± 0.00) mRNA and protein were increased and the expression of SOD-1 (0.28 ± 0.02) mRNA and protein was decreased ( P < 0.05). Increased expression of Bax (3.54 ± 0.00) and caspase 3 (4.18 ± 0.01) mRNA and protein inhibited the expression of Bcl-2 (0.39 ± 0.02) mRNA and protein. The changes of pulmonary edema, inflammatory cell infiltration, and cell damage factor expression increased gradually with time, and reached the peak at 12-24 h after the outbreak, and returned to normal at 7-14 days. Detonation injury can lead to edema of lung tissue, pulmonary hemorrhage, rupture of pulmonary vessels, induction of early inflammatory responses accompanied by increased oxidative stress in lung tissue cells and increased apoptosis in mice experiencing blast injury. The above results are consistent with those reported in other literatures. It is showed that the mouse lung blast injury model is successfully modeled, and the device can be used for the study of pulmonary blast injury. Impact statement The number of patients with explosive injury has increased year by year, but there is no better treatment. However, the research on detonation injury is difficult to carry out. One of the factors is the difficulty in making the model of blast injury. The laboratory successfully developed and produced a simulation device of explosive knocking through a large amount of literature data and preliminary experiments, and verified the preparation of the simulation device through various experimental techniques. The results showed that the device could simulate the shock wave-induced acute lung injury generated, which was similar to the actual knocking injury. The experimental process was controlled. Under the same condition, there was no statistical difference between the groups. It is possible to realize miniaturization and precision of an explosive knocking simulation device, which is a good experimental tool for further research on the mechanism of organ damage caused by detonation and the development of protective drugs.

Purpose: The present study investigated different doses of ultraviolet-A (UV-A) light on plasma nitric oxide metabolites and cardiorespiratory variables., Methods: Ten healthy male participants completed three experimental conditions, 7 days apart. Participants were exposed to no light (CON); 10 J cm 2 (15 min) of UV-A light (UVA10) and 20 J cm 2 (30 min) of UV-A light (UVA20) in a randomized order. Plasma nitrite [NO 2 - ] and nitrate [NO 3 - ] concentrations, blood pressure (BP), and heart rate (HR) were recorded before, immediately after exposure and 30 min post-exposure. Whole body oxygen utilization ([Formula: see text]), resting metabolic rate (RMR) and skin temperature were recorded continuously., Results: None of the measured parameters changed significantly during CON (all P > 0.05). [Formula: see text] and RMR were significantly reduced immediately after UVA10 (P < 0.05) despite no change in plasma [NO 2 - ] (P > 0.05). Immediately after exposure to UVA20, plasma [NO 2 - ] was higher (P = 0.014) and [Formula: see text] and RMR tended to be lower compared to baseline (P = 0.06). There were no differences in [NO 2 - ] or [Formula: see text] at the 30 min time point in any condition. UV-A exposure did not alter systolic BP, diastolic BP or MAP (all P > 0.05). UV-A light did not alter plasma [NO 3 - ] at any time point (all P > 0.05)., Conclusions: This study demonstrates that a UV-A dose of 20 J cm 2 is necessary to increase plasma [NO 2 - ] although a smaller dose is capable of reducing [Formula: see text] and RMR at rest. Exposure to UV-A did not significantly reduce BP in this cohort of healthy adults. These data suggest that exposure to sunlight has a meaningful acute impact on metabolic function.

Background: The cardiovascular effects of low-level environmental radiation exposures are poorly understood. Although particulate matter (PM) has been linked to cardiovascular morbidity and mortality, and elevated blood pressure (BP), the properties promoting its toxicity remain uncertain. Addressing a knowledge gap, we evaluated whether BP increased with higher exposures to radioactive components of ambient PM, herein referred to as particle radioactivity (PR)., Methods and Results: We performed a repeated-measures analysis of 852 men to examine associations between PR exposure and BP using mixed-effects regression models. As a surrogate for PR, we used gross β activity, measured by the US Environmental Protection Agency's radiation monitoring network. Higher PR exposure was associated with increases in both diastolic BP and systolic BP, for exposures from 1 to 28 days. An interquartile range increase in 28-day PR exposure was associated with a 2.95-mm Hg increase in diastolic BP (95% confidence interval, 2.25-3.66; P <0.001) and a 3.94-mm Hg increase in systolic BP (95% confidence interval, 2.62-5.27; P <0.001). For models including both PR and PM ≤2.5 µm, the PR-BP associations remained stable and significant. For models including PR and black carbon or PR and particle number, the PR-BP associations were attenuated; however, they remained significant for many exposure durations., Conclusions: This is the first study to demonstrate the potential adverse effects of PR on both systolic and diastolic BPs. These were independent and similar in magnitude to those of PM ≤2.5 µm, black carbon, and particle number. Understanding the effects of particle-bound radionuclide exposures on BP may have important implications for environmental and public health policy., (© 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)

Background: Radiotherapy (RT) plays a key role in the management of head and neck cancer (HNC), especially in locally advanced disease. Patients undergoing head and neck RT, especially elderly ones, are suffering from low and labile blood pressure (BP) during the treatment. They complain of weakness and fatigue and are prone to recurrent falls. The aim of this study was to characterize BP changes during RT period., Methods: Patients with HNC, receiving radiation to the neck, were recruited from Sheba medical center RT unit. Office BP, orthostatic measurements, 24-hour ambulatory BP monitoring, body weight, and metabolic parameters were measured at baseline after 30 days and after 90 days from beginning of therapy., Results: Nineteen patients (17 males), 64 ± 12 years old were recruited. Nine hypertensive patients continued their antihypertensive treatment during the study. Office systolic BP and diastolic BP decreased significantly after 30 days (128 ± 4/80 ± 3 to 122 ± 3/74 ± 3 mm Hg; P < 0.05). Average 24-hour BP values after 30 days of RT decreased from 130 ± 3/76 ± 2 to 123 ± 3/71 ± 2 mm Hg; P < 0.05. A similar trend was observed for day and night BP levels. Decrease in office and ambulatory BP was sustained for several months after RT completion. No orthostasis was observed during the study period. Patient lost weight significantly during the study period. However, BP changes were independent of weight loss., Conclusion: There is a significant and sustained BP reduction after head and neck RT, without orthostatic changes. Clinicians should be aware of this phenomenon and consider treatment adaption accordingly., (© American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com)

Background: Head and neck radiation therapy (HNRT) impairs baroreflex sensitivity, and it may potentiate the effects of anesthetics on heart rate (HR) and blood pressure (BP) regulation. Currently, the impacts of HNRT on HR and BP under anesthesia remain unclear., Methods: In this study, 472 patients with primary oral cavity or oropharyngeal cancer at all stages were examined. Half of the patients underwent HNRT plus surgery. The other half underwent surgery only and was matched with the treatment patients according to age, sex, and body mass index at a 1:1 ratio. The HRs and BPs in the 2 groups during anesthetic induction, skin incision, and emergence were compared retrospectively. A multivariable model of repeated measures with unstructured covariance structure was used to examine the associations of HNRT with intraoperative HRs and BPs after adjusting for baseline HR and BP, time, use of β-blockers, history of chemotherapy, and American Society of Anesthesiologists physical status score. BPs and HRs were collected every 5 minutes. The baseline HR and BP measurements were not included in the outcome vector and were only used as adjustment for baselines., Results: Compared with corresponding baseline values in controls, the baseline HR was significantly higher (P = .0012) and the baseline systolic BP was lower (P < .0001) in the treatment group. The baseline diastolic BP levels did not differ significantly (P = .6411). Fewer patients receiving HNRT than controls took β-blockers daily (17% vs 28%; P = .0041). Comparing the corresponding values in control and treatment groups, multivariable analysis revealed significant associations of HNRT with decreases in HR during anesthesia induction (-2.21 [95% confidence interval {CI}, -4.42 to -0.01]; P = .0492) and skin incision (-2.66 [95% CI, -5.16 to -0.16]; P = .0373) and of HNRT with decreases in systolic BP during anesthesia induction (-6.88 [95% CI, -10.99 to -2.78]; P = .0011) and skin incision (-15.87 [95% CI, -20.45 to -11.29]; P < .001). However, we observed a significant association of HNRT with decrease in diastolic BP only during skin incision (-6.50 [95% CI, -9.47 to -3.53]; P < .0001)., Conclusions: The significant finding in the study was that general anesthesia imposed a negative chronotropic effect on HR in the group given HNRT. Therefore, one should be watchful for bradycardia in these patients; particularly those with low BPs. Their hemodynamics may rapidly progress into an unstable status when bradycardia and hypotension develop altogether.

Background: Due to different physical and biological mechanisms behind ultrasound hyperthermia and phonophoresis, the requirement for ultrasound power, frequency and control modes varies., Objective: This paper introduces an adaptive ultrasonic physiotherapy system based on real-time surveillance over physiological characteristics of the patients, which in turn assists the individual treatment and dose limitation in auxiliary rehabilitation., Methods: The method essentially takes advantage of distinctive characteristics of two different phases (systole and diastole) of the human cardiac cycle as a medium for modulation. The abundance of blood flow during systole enables energy exchange for hyperthermia while blood flow insufficiency caused by diastole assists in drug penetration. Said method could improve the adjuvant therapy as it provides partial drug penetration and therapeutic dosage control., Results: By adjusting time window and intensity of multi-frequency ultrasound, it is possible to reduce the irradiation dosage to around 22% of that during continuous irradiation at 1 MHz. The method shows high potential in clinical practice., Conclusion: Frequency-tuning ultrasound therapy would be more efficient regarding drug penetration and improve the therapeutic efficacy of hyperthermia.

Purpose: The baroreflex is an important afferent mechanism controlling autonomic functions. As afferent nerves course through the neck, they are susceptible to damage by neck irradiation in head and neck cancer patients. With increased survival of head and neck cancer patients because of improved therapy, the cardiovascular morbidity and mortality in them have become apparent and this is of clinical concern. There are few case reports of baroreflex failure as a chronic sequel to neck irradiation., Objectives: The present study evaluated the changes in cardio-autonomic tone and postural cardiovascular reflex in neck-irradiated patients., Methods: Head and neck cancer patients who had received neck irradiation (n = 15) and healthy controls (n = 15) were evaluated for heart rate variability with time domain analysis of 5 min ECG recording. Postural cardiovascular reflexes were studied with changes in blood pressure and heart rate in the lying to standing test., Results: Our results suggest that there is a reduction in overall time domain measures of heart rate variability and weakened postural reflexes in neck-irradiated patients., Conclusion: Decreased heart rate variability in neck-irradiated patients reflects an independent risk of cardiovascular morbidity. The early detection of cardiovascular impairment in such patients may help healthcare professionals in providing better care. Furthermore, the dose delivered to the carotid sinus should be monitored and restricted.

Purpose: It has been shown that chronic exposure of young spontaneously hypertensive rats (SHR) to static magnetic field (SMF) delays the development of overt hypertension. Therefore the aim of the present work was to investigate the effects of SMF on autonomic cardiovascular control in adult spontaneously hypertensive rats., Materials and Methods: Experiments were performed in freely moving spontaneously hypertensive rats equipped with femoral arterial catheter for blood pressure recording. Spontaneously hypertensive rats were exposed for 30 days to upward-oriented SMF (n = 17) or downward-oriented SMF (n = 17) of 16 mT intensity. A control group of spontaneously hypertensive rats (n = 17) was not exposed to SMF. Neurogenic cardiovascular control was evaluated by spectral analysis of arterial blood pressure and heart rate short-term variability and baro-receptor reflex sensitivity using the sequence method., Results: Exposure of spontaneously hypertensive rats to both upward- and downward-oriented SMF significantly reduced arterial blood pressure and enhanced baro-receptor reflex sensitivity. Downward-oriented SMF reduced heart rate, too. SMF of either orientation reduced systolic blood pressure variability in very low frequency domain while downward-oriented SMF also reduced low-frequency and increased high frequency domains., Conclusion: It follows that prolonged exposure to SMF is beneficial for neurogenic cardiovascular control in hypertension.

Background: In spite of more than 100 years of investigations the question of whether a reduced sodium intake improves health is still unsolved., Objectives: To estimate the effects of low sodium intake versus high sodium intake on systolic and diastolic blood pressure (SBP and DBP), plasma or serum levels of renin, aldosterone, catecholamines, cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and triglycerides., Search Methods: The Cochrane Hypertension Information Specialist searched the following databases for randomized controlled trials up to March 2016: the Cochrane Hypertension Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (2016, Issue 3), MEDLINE (from 1946), Embase (from 1974), the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also searched the reference lists of relevant articles., Selection Criteria: Studies randomising persons to low-sodium and high-sodium diets were included if they evaluated at least one of the above outcome parameters., Data Collection and Analysis: Two review authors independently collected data, which were analysed with Review Manager 5.3., Main Results: A total of 185 studies were included. The average sodium intake was reduced from 201 mmol/day (corresponding to high usual level) to 66 mmol/day (corresponding to the recommended level).The effect of sodium reduction on blood pressure (BP) was as follows: white people with normotension: SBP: mean difference (MD) -1.09 mmHg (95% confidence interval (CI): -1.63 to -0.56; P = 0.0001); 89 studies, 8569 participants; DBP: + 0.03 mmHg (MD 95% CI: -0.37 to 0.43; P = 0.89); 90 studies, 8833 participants. High-quality evidence. Black people with normotension: SBP: MD -4.02 mmHg (95% CI:-7.37 to -0.68; P = 0.002); seven studies, 506 participants; DBP: MD -2.01 mmHg (95% CI:-4.37 to 0.35; P = 0.09); seven studies, 506 participants. Moderate-quality evidence. Asian people with normotension: SBP: MD -0.72 mmHg (95% CI: -3.86 to 2.41; P = 0.65); DBP: MD -1.63 mmHg (95% CI:-3.35 to 0.08; P =0.06); three studies, 393 participants. Moderate-quality evidence.White people with hypertension: SBP: MD -5.51 mmHg (95% CI: -6.45 to -4.57; P < 0.00001); 84 studies, 5925 participants; DBP: MD -2.88 mmHg (95% CI: -3.44 to -2.32; P < 0.00001); 85 studies, 6001 participants. High-quality evidence. Black people with hypertension: SBP MD -6.64 mmHg (95% CI:-9.00 to -4.27; P = 0.00001); eight studies, 619 participants; DBP -2.91 mmHg (95% CI:-4.52, -1.30; P = 0.0004); eight studies, 619 participants. Moderate-quality evidence. Asian people with hypertension: SBP: MD -7.75 mmHg (95% CI:-11,44 to -4.07; P < 0.0001) nine studies, 501 participants; DBP: MD -2.68 mmHg (95% CI: -4.21 to -1.15; P = 0.0006). Moderate-quality evidence.In plasma or serum, there was a significant increase in renin (P < 0.00001), aldosterone (P < 0.00001), noradrenaline (P < 0.00001), adrenaline (P < 0.03), cholesterol (P < 0.0005) and triglyceride (P < 0.0006) with low sodium intake as compared with high sodium intake. All effects were stable in 125 study populations with a sodium intake below 250 mmol/day and a sodium reduction intervention of at least one week., Authors' Conclusions: Sodium reduction from an average high usual sodium intake level (201 mmol/day) to an average level of 66 mmol/day, which is below the recommended upper level of 100 mmol/day (5.8 g salt), resulted in a decrease in SBP/DBP of 1/0 mmHg in white participants with normotension and a decrease in SBP/DBP of 5.5/2.9 mmHg in white participants with hypertension. A few studies showed that these effects in black and Asian populations were greater. The effects on hormones and lipids were similar in people with normotension and hypertension. Renin increased 1.60 ng/mL/hour (55%); aldosterone increased 97.81 pg/mL (127%); adrenalin increased 7.55 pg/mL (14%); noradrenalin increased 63.56 pg/mL: (27%); cholesterol increased 5.59 mg/dL (2.9%); triglyceride increased 7.04 mg/dL (6.3%).

The detrimental effects of ultraviolet radiation are well known. Skin cancer, photo-aging, and induction or exacerbation of photosensitive dermatoses have been the focus of most photobiological research since 1928 when Findlay confirmed the carcinogenicity of ultraviolet radiation using a murine model of skin cancer. The epidemiological, mechanistic and clinical trial data have enabled the classification by the International Agency for Research on Cancer of ultraviolet radiation as a Group 1 ('sufficient evidence') carcinogen for human skin. Public health advice in most developed countries with a pale-skinned population following this has advocated limiting exposure to sunlight through use of clothing, sunblock and behavioural alterations. Despite this plethora of data, one striking omission is evidence that ultraviolet radiation shortens life, and as I will lay out in this chapter, epidemiological and now mechanistic data suggest that UV may have significant benefits on health and in particular cardiovascular health.

The feasibility of implementing magnetic struts into drug-eluting stents (DESs) to mitigate the adverse hemodynamics which precipitate stent thrombosis is examined. These adverse hemodynamics include platelet-activating high wall shear stresses (WSS) and endothelial dysfunction-inducing low wall shear stresses. By magnetizing the stent struts, two forces are induced on the surrounding blood: (1) magnetization forces which reorient red blood cells to align with the magnetic field and (2) Lorentz forces which oppose the motion of the conducting fluid. The aim of this study was to investigate whether these forces can be used to locally alter blood flow in a manner that alleviates the thrombogenicity of stented vessels. Two-dimensional steady-state computational fluid dynamics (CFD) simulations were used to numerically model blood flow over a single magnetic drug-eluting stent strut with a square cross section. The effects of magnet orientation and magnetic flux density on the hemodynamics of the stented vessel were elucidated in vessels transporting oxygenated and deoxygenated blood. The simulations are compared in terms of the size of separated flow regions. The results indicate that unrealistically strong magnets would be required to achieve even modest hemodynamic improvements and that the magnetic strut concept is ill-suited to mitigate stent thrombosis.

Several studies have explored the hypothesis that low blood lead (PbB) and high noise levels may be associated with an increased risk of hypertension. To assess the possible relationship between occupational exposure to lead (Pb) and noise and elevated blood pressure, we studied 105 workers (age: 41.27 ± 6.25 years and length of employment: 4.12 ± 5.33 years) employed in a Pb battery recycling plant by measuring A-weighted equivalent sound level, PbB, δ-aminolevulinic acid dehydratase (ALAD) activity and zinc protoporphyrin (ZPP) levels and systolic and diastolic blood pressure (SBP and DBP). Results showed that occupational exposure to higher ambient Pb and noise levels was related to slightly increased SBP and DBP. PbB values correlated significantly with SBP and DBP, whereas noise levels correlated neither with SBP nor with DBP. Furthermore, workers exposed to higher ambient Pb had higher PbB and ZPP and showed more decreased ALAD activity. Blood pressure does not correlate with noise exposure but only with PbB concentration., (© The Author(s) 2015.)

Chronic kidney disease is a known complication of hematopoietic stem cell transplant (HSCT) and can be caused by irradiation at the time of the HSCT. In our rat model there is a 6- to 8-wk latent period after irradiation that leads to the development of proteinuria, azotemia, and hypertension. The current study tested the hypothesis that decreased endothelial-derived factors contribute to impaired afferent arteriolar function in rats exposed to total body irradiation (TBI). WAG/RijCmcr rats underwent 11 Gy TBI, and afferent arteriolar responses to acetylcholine were determined at 1, 3, and 6 wk. Blood pressure and blood urea nitrogen were not different between control and irradiated rats. Afferent arteriolar diameters were not altered in irradiated rats. Impaired endothelial-dependent responses to acetylcholine were evident at 3 and 6 wk following TBI. Nitric oxide synthase (NOS), cyclooxygenase (COX), and epoxygenase (EPOX) contribution to acetylcholine dilator responses were evaluated. NOS inhibition with N(G)-nitro-l-arginine methyl ester (l-NAME) reduced acetylcholine responses by 50% in controls and 90% in 3-wk TBI rats. COX inhibition with indomethacin did not significantly alter the acetylcholine response in the presence or absence of l-NAME. EPOX inhibition with N-methylsulfonyl-6-(2-propargyloxyphenyl)hexanamide significantly decreased acetylcholine responses (35%) in controls but did not significantly alter acetylcholine responses (4%) in TBI rats. Biochemical analysis revealed decreased urinary EPOX metabolites but no change in COX, NOS, or reactive oxygen species at 3 wk TBI. Taken together, these results indicate that afferent arteriolar endothelial dysfunction involves a decrease in EPOX metabolites that precedes the development of proteinuria, azotemia, and hypertension in irradiated rats.

Background: High blood pressure (BP) is the leading risk factor for disability adjusted life years lost globally. Epidemiological data show a correlation between increased sun exposure and reduced population BP and cardiovascular mortality. Individuals with high serum vitamin D levels are at reduced risk of hypertension, cardiovascular disease and metabolic syndrome, yet multiple trial data show that oral vitamin D supplementation has no effect on these endpoints. Sunlight is a risk factor for skin cancers, but no link has been shown with increased all-cause mortality. Cohort studies from Scandinavia show a dose-dependent fall in mortality with increased sun-seeking behaviour. Skin contains significant stores of nitrogen oxides, which can be converted to NO by UV radiation and exported to the systemic circulation. Human studies show that this pathway can cause arterial vasodilatation and reduced BP. Murine studies suggest the same mechanism may reduce metabolic syndrome., Summary: Sunlight has beneficial effects on cardiovascular risk factors independently of vitamin D., Key Messages: All-cause mortality should be the primary determinant of public health messages. Sunlight is a risk factor for skin cancer, but sun avoidance may carry more of a cost than benefit for overall good health., (© 2016 S. Karger AG, Basel.)

Electrocardiogram and arterial pressure measurements were studied under acute exposures to WIFI (2.45GHz) during one hour in adult male rabbits. Antennas of WIFI were placed at 25cm at the right side near the heart. Acute exposure of rabbits to WIFI increased heart frequency (+22%) and arterial blood pressure (+14%). Moreover, analysis of ECG revealed that WIFI induced a combined increase of PR and QT intervals. By contrast, the same exposure failed to alter maximum amplitude and P waves. After intravenously injection of dopamine (0.50ml/kg) and epinephrine (0.50ml/kg) under acute exposure to RF we found that, WIFI alter catecholamines (dopamine, epinephrine) action on heart variability and blood pressure compared to control. These results suggest for the first time, as far as we know, that exposure to WIFI affect heart rhythm, blood pressure, and catecholamines efficacy on cardiovascular system; indicating that radiofrequency can act directly and/or indirectly on cardiovascular system., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background and Purpose: Neoadjuvant chemoradiation (nCRT) followed by surgery is considered curative intent treatment for patients with resectable esophageal cancer. The aim was to establish hemodynamic aspects of changes in heart volume and to explore whether changes in heart volume resulted in clinically relevant changes in the dose distribution of radiotherapy., Methods: A prospective study was conducted in patients who were treated with nCRT consisting of carboplatin and paclitaxel concomitant with radiotherapy (41.4 Gy/1.8 Gy per fraction). Physical parameters, cardiac volume on CT and Cone beam CT, cardiac blood markers and cardiac ultrasound were obtained., Results: In 23 patients a significant decrease of 55.3 ml in heart volume was detected (95% CI 36.7-73.8 ml, p<0.001). There was a decrease in both systolic (mean decrease 18 mmHg, 95% CI 11-26 mmHg, p<0.001) and diastolic blood pressure (mean decrease 8 mmHg, 95% CI 2-14 mmHg, p=0.008) and an increase in heart rate with 6 beats/min (95% CI 1-11 beats/min, p=0.021). Except for Troponin T, no change in other cardiac markers and echocardiography parameters were observed. The change in heart volume did not result in a clinically relevant change in radiation dose distribution., Conclusion: Heart volume was significantly reduced, but was not accompanied by overt cardiac dysfunction. All observed changes in hemodynamic parameters are consistent with volume depletion. Adaptation of the treatment plan during the course of radiotherapy is not advocated., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

The increasing prevalence of metabolic syndrome (MetS) has become an important issue worldwide. Metabolic comorbidities of hypertension, obesity, and hyperlipidemia are shown as important risk factors for incident gout. The purpose of this study was to investigate the relationship between hyperuricemia and MetS. This is a cross-sectional study. The effective sample included 21,544 individuals who received worker health examinations at a local teaching hospital in Changhua County from 2008~2012. We used multiple logistic regression analysis to investigate the influences of hyperuricemia on MetS. The results showed that individuals with MetS had significantly higher blood pressure, fasting plasma glucose, triglycerides, waist circumference, and high-density lipoprotein cholesterol than those without MetS (P < 0.001). Multiple logistic regression analysis revealed hyperuricemia to be an important factor of MetS. The risk of developing MetS is higher with high levels of serum uric acid (SUA) and the odds ratio (OR) of having MetS is 4.98 times higher for Tertile 3 than for Tertile 1 (95% CI = 4.16-5.97) and 4 times higher for Quartile 4 than for Quartile 1 (95% CI = 3.59-4.46). In conclusion, males are more likely to develop MetS than females, and the risk of having MetS increases with age and SUA concentration.

Carotid baroreceptor stimulation can treat resistant hypertension with possible effects on the vasculature beyond the decrease in arterial pressure. This study aims to characterize age-dependency of vascular hemodynamics changes with unilateral field stimulation of carotid baroreceptors in normotensive rats to infer underlying hemodynamic mechanisms. Anesthetized Wistar-Kyoto rats divided into two groups (young: n=10, 13-33 weeks; old: n=6, 52-58 weeks) were instrumented to measure heart rate (HR) and mean arterial pressure (MAP), and flow in the abdominal aorta and renal artery. Measures of aortic and renal artery stiffness and resistance were calculated. Baroreceptor stimulation caused a consistent reduction in MAP, HR, pulse pressure and aortic pulse wave velocity. In young rats reduced MAP (77 ± 10 to 64 ± 13 mmHg, p<;0.001) was concomitant with reduced mean aortic (40 ± 15 to 32 ± 11 ml/min, p<;0.05) and renal flow (3.0 ± 1.6 2.2 ± 1.1 ml/min, p<;0.001). However, in old rats reduced MAP (76 ± 14 to 64 ± 10 mmHg, p<;0.05) occurred with a reduced aortic resistance (1.8 ± 0.9 to 1.6 ± 0.9 mmHg.min/ml, p<;0.05), renal artery resistance (17.4 ± 2.4 to 16.5 ± 2.3 mmHg.min/ml, p<;0.05) and mean renal flow (4.5 ± 1.2 to 4.0 ± 1.1 ml/min, p<;0.05). This was consistent with reduced characteristic impedance in older rats in both the aorta (0.17 ± 0.08 to 0.13 ± 0.08 mmHg.min/ml, p<;0.05) and renal artery (4.97 ± 1.16 to 3.97 ± 1.08 mmHg.min/ml, p<;0.05). Stimulation caused a leftward shift in renal impedance phase frequency spectrum in both age groups indicating changes in wave reflection from the renal bed. Findings show that the reduction in MAP due to carotid barostimulation is associated with different hemodynamic mechanisms that depend on age.

Aims: We aimed to investigate the anti-hypertensive effect of radiofrequency (RF) renal denervation (RDN) in an animal model of hypertension., Materials and Methods: RF energy was delivered to bilateral renal arteries through a 2 Fr catheter with opening abdomen in 8 spontaneously hypertensive rats (SHRs) and 8 Wistar-Kyoto rats (WKYs). Sham operation was performed in other 8 SHRs and 8 WKYs. Blood pressure (BP), heart rate (HR), and urinary norepinephrine excretion were followed up for 3 months. Plasma and renal tissue concentrations of norepinephrine and plasma renin activity were measured 3 months after the procedure. The RDN was confirmed by a decrease in renal tissue norepinephrine., Key Findings: RF-RDN restrained a spontaneous rise in systolic BP (46 ± 12% increase from 158 ± 8 to 230 ± 14 mmHg vs. 21 ± 18% increase from 165 ± 9 to 197 ± 20 mmHg, p = 0.01) and diastolic BP (55 ± 27% increase from 117 ± 9 to 179 ± 23 mmHg vs. 28 ± 13% increase from 120 ± 7 to 154 ± 13 mmHg, p = 0.04) in SHRs; however, WKYs were not affected. Although there were no changes in HR and systemic norepinephrine, the renal tissue norepinephrine was decreased by RF-RDN in both SHR (302 ± 41 vs. 159 ± 44 ng/g kidney, p<0.01) and WKY (203 ± 33 vs. 145 ± 26 ng/g kidney, p = 0.01). Plasma renin activity was reduced by the RF-RDN only in SHR (35.3 ± 9.5 vs. 21.4 ± 8.6 ng/mL/h, p<0.01)., Significance: RF-RDN demonstrated an anti-hypertensive effect with a reduction of renal tissue norepinephrine and plasma renin activity in SHR., (Copyright © 2014 Elsevier Inc. All rights reserved.)

UVR has deleterious and beneficial effects on human health. In this issue, Liu et al. (2014) show that UVA decreases blood pressure and increases blood flow and heart rate in humans, which is beneficial to the cardiovascular system. This is likely mediated by UVA causing release of nitric oxide (NO) from skin stores. This mediator may have additional effects on human health.

The incidence of hypertension and cardiovascular disease (CVD) correlates with latitude and rises in winter. The molecular basis for this remains obscure. As nitric oxide (NO) metabolites are abundant in human skin, we hypothesized that exposure to UVA may mobilize NO bioactivity into the circulation to exert beneficial cardiovascular effects independently of vitamin D. In 24 healthy volunteers, irradiation of the skin with two standard erythemal doses of UVA lowered blood pressure (BP), with concomitant decreases in circulating nitrate and rises in nitrite concentrations. Unexpectedly, acute dietary intervention aimed at modulating systemic nitrate availability had no effect on UV-induced hemodynamic changes, indicating that cardiovascular effects were not mediated via direct utilization of circulating nitrate. UVA irradiation of the forearm caused increased blood flow independently of NO synthase (NOS) activity, suggesting involvement of pre-formed cutaneous NO stores. Confocal fluorescence microscopy studies of human skin pre-labeled with the NO-imaging probe diaminofluorescein 2 diacetate revealed that UVA-induced NO release occurs in a NOS-independent, dose-dependent manner, with the majority of the light-sensitive NO pool in the upper epidermis. Collectively, our data provide mechanistic insights into an important function of the skin in modulating systemic NO bioavailability, which may account for the latitudinal and seasonal variations of BP and CVD.

Circadian misalignment between internal and environmental rhythms dysregulates blood pressure (BP) variability because of disruption of the biological clock, resulting in increased nighttime BP. Although exposure to light-at-night is associated with the circadian misalignment, it remains unclear whether exposure to light-at-night in home settings is associated with nighttime BP. In this cross-sectional analysis of 528 elderly individuals (mean age: 72.8 years), we measured bedroom light intensity at 1-min intervals on two consecutive nights along with ambulatory BP, overnight urinary melatonin excretion and actigraphy. With regard to adjusted mean comparisons using analysis of covariance, the light-at-night group (average: ≥5 lux; n = 109) showed significantly higher nighttime systolic BP (SBP; adjusted mean: 120.8 vs. 116.5 mmHg, p = 0.01) and diastolic BP (70.1 vs. 67.1 mmHg, p < 0.01) compared with the Darker group (average: <5 lux; n = 419) independently of potential confounding factors including overnight urinary melatonin excretion and actigraphic sleep quality. We observed consistent associations between light-at-night and nighttime BP in different cutoff values for light-at-night intensity (i.e. 3 and 10 lux). In conclusion, exposure to light-at-night in home settings is significantly associated with increased nighttime BP in elderly individuals independently of overnight urinary melatonin excretion. A 4.3 mmHg increase in nighttime SBP is associated with a 6.1% increase in total mortality, which corresponds to approximately 10 000 annual excess deaths in Japanese elderly population.

This study investigated the effects of ANG II on slow and rapid baroreflex responses of barosensitive bulbospinal neurons in the rostral ventrolateral medulla (RVLM) in urethane-anesthetized rabbits to determine whether the sympathetic baroreflex modulation induced by application of ANG II into the RVLM can be explained by the total action of ANG II on individual RVLM neurons. In response to pharmacologically induced slow ramp changes in mean arterial pressure (MAP), individual RVLM neurons exhibited a unit activity-MAP relationship that was fitted by a straight line with upper and lower plateaus. Iontophoretically applied ANG II raised the upper plateau without changing the slope, and, thereby, increased the working range of the baroreflex response. An asymmetric sigmoid curve that was determined by averaging individual unit activity-MAP relationship lines became more symmetric with ANG II application. The characteristics of the average curves, both before and during ANG II application, were consistent with the renal sympathetic nerve activity-MAP relationship curves obtained under the same experimental conditions. ANG II also affected rapid baroreflex responses of RVLM neurons that were induced by cardiac beats, as application of ANG II predominantly raised the average unit activities in the downstroke phase of arterial pulse waves. The present study provides a possible explanation for the ANG II-induced sympathetic baroreflex modulation based on the action of ANG II on barosensitive bulbospinal RVLM neurons. Our results also suggest that ANG II changes both static and dynamic characteristics of baroreflex responses of RVLM neurons.

Previous studies showed that adverse effect of ionizing radiation on the cardiovascular system is beside other factors mostly mediated by reactive oxygen and nitrogen species, which deplete antioxidant stores. One of the structures highly sensitive to radicals is the Na,K-ATPase the main system responsible for extrusion of superfluous Na(+) out of the cell which utilizes the energy derived from ATP. The aim of present study was the investigation of functional properties of cardiac Na,K-ATPase in 20-week-old male rats 6 weeks after γ-irradiation by a dose 25 Gy (IR). Irradiation induced decrease of systolic blood pressure from 133 in controls to 85 mmHg in IR group together with hypertrophy of right ventricle (RV) and hypotrophy of left ventricle (LV). When activating the cardiac Na,K-ATPase with substrate, its activity was lower in IR in the whole concentration range of ATP. Evaluation of kinetic parameters revealed a decrease of the maximum velocity (V max) by 40 % with no changes in the value of Michaelis-Menten constant (K m). During activation with Na(+), we observed a decrease of the enzyme activity in hearts from IR at all tested Na(+) concentrations. The value of V max decreased by 38 %, and the concentration of Na(+) that gives half maximal reaction velocity (K Na) increased by 62 %. This impairment in the affinity of the Na(+)-binding site together with decreased number of active Na,K-ATPase molecules, as indicated by lowered V max values, are probably responsible for the deteriorated efflux of the excessive Na(+) from the intracellular space in hearts of irradiated rats.

Objective: Applying shock waves to the heart has been reported to stimulate the heart and alter cardiac function. We hypothesized that shock waves could be used to diagnose regional viability., Method: We used a Langendorff model to investigate the acute effects of shock waves at different energy levels and times related to systole, cycle duration and myocardial function., Results: We found only a small time window to use shock waves. Myocardial fibrillation or extrasystolic beats will occur if the shock wave is placed more than 15 ms before or 30 ms after the onset of systole. Increased contractility and augmented relaxation were observed after the second beat, and these effects decreased after prolonging the shock wave delay from 15 ms before to 30 ms after the onset of systole. An energy dependency could be found only after short delays (-15 ms). The involved processes might include post-extrasystolic potentiation and simultaneous pacing., Conclusion: In summary, we found that low-energy shock waves can be a useful tool to stimulate the myocardium at a distance and influence function., (Copyright © 2013 Elsevier B.V. All rights reserved.)

This double-blind study tested the effects of pulsating electromagnetic field (PEMF) therapy sessions on the changes in peripheral cardiovascular function in a group of aging adults after 12 weeks of treatment. Each therapy session involved 15 min of exposure to low-frequency PEMF with asymmetrical waveforms emitted by the Impulser™ Pro mattress. The treatment was provided 5 days per week for a total of 60 sessions. Resting blood pressure and arterial stiffness index were determined for peripheral cardiovascular function. Fifty-four older men and women (mean age 59.8 ± 3.5 yrs) completed the entire protocol involving either the PEMF or a sham treatment. The results include statistically significant reductions in systolic and pulse blood pressure, while no significant difference in diastolic pressure or the index of arterial stiffness was observed. These findings suggest that the PEMF treatment might be linked to improvements in peripheral resistance or circulation.

Reduced aerobic fitness is associated with an increased risk of cardiovascular diseases among the older population. The aim of this study was to investigate the effects of LED irradiation (850 nm) applied during treadmill training on the maximal exercise tolerance in postmenopausal women. At the beginning of the study, 45 postmenopausal women were assigned randomly to three groups, and 30 women completed the entire 6 months of the study. The groups were: (1) the LED group (treadmill training associated with phototherapy, n = 10), (2) the exercise group (treadmill training, n = 10), and (3) the sedentary group (neither physical training nor phototherapy, n = 10). The training was performed for 45 min twice a week for 6 months at intensities between 85% and 90% maximal heart rate (HRmax). The irradiation parameters were 39 mW/cm(2), 45 min and 108 J/cm(2). The cardiovascular parameters were measured at baseline and after 6 months. As expected, no significant differences were found in the sedentary group (p ≥ 0.05). The maximal time of tolerance (Tlim), metabolic equivalents (METs) and Bruce stage reached significantly higher values in the LED group and the exercise group (p < 0.01). Furthermore, the HR, double product and Borg score at isotime were significantly lower in the LED group and in the exercise group (p < 0.05). However, the time of recovery showed a significant decrease only in the LED group (p = 0.003). Moreover, the differences between before and after training (delta values) for the Tlim, METs and HR at isotime were greater in the LED group than in the exercise group with a significant intergroup difference (p < 0.05). Therefore, the infrared LED irradiation during treadmill training can improve maximal performance and post-exercise recovery in postmenopausal women.