Exercise mitigates the effects of hyperhomocysteinemia on adverse skeletal muscle remodeling.

Background: Hyperhomocysteinemia (HHcy) is heavily implicated in diabetes and cardiovascular disease. HHcy is known for causing inflammation and vascular remodeling, particularly through production of reactive oxygen species (ROS) and matrix metalloproteinase-9 (MMP-9). Although its impact on skeletal muscle is rather unclear, HHcy is known to cause skeletal muscle weakness and functional impairment. The impact of HHcy on inflammation makes it seem likely that HHcy causes skeletal muscle fibrosis through induction of inflammatory factors and destructive macrophages. Exercise has been shown to reduce homocysteine levels and therefore, could serve as a promising intervention for HHcy. The purpose of this study was to investigate whether HHcy causes skeletal muscle fibrosis through induction of inflammation and determine if exercise can mitigate these effects. Methods: For these experiments we used J774A.1 and Raw 264.7 macrophages in cell culture and C57, CBS+/-, FVB, MMP-9 -/-, and CBS/MMP-9 double KO mice for animal models. A 6 week treadmill exercise protocol was used as intervention for HHcy. Arterial blood pressure measures were taken through tail-cuff method. Hind limb perfusion was measure via laser Doppler. Plasma Hcy estimations were measured thorugh dot blot. Measurement of skeletal muscle or macrophage protein expression occurred through the use of western blot, immunocytochemistry or immunohistochemistry. Levels of skeletal muscle mRNA expression were determined through PCR and qPCR. Collagen deposition in the skeletal muscle was measured using Masson’s trichrome staining. ROS production in macrophages was measured using a DCFDA assay. Results: In CBS+/- mice, increased plasma Hcy levels were associated with decreased body weight and muscle mass, femoral artery perfusion, femoral artery lumen diameter and oxidative metabolism. These mice displayed increased wall to lumen ratio, mean arterial blood pressure, collagen deposition and elevated myostatin protein expression. It was determined that CBS/MMP-9 mice did not display any of these conditions. Exercise was capable of mitigating all of these effects in CBS +/- mice. Skeletal muscle from CBS+/- mice had elevated markers of inflammation and hypoxia including VEGF, iNOS, EMMPRIN, MMP-9, and IL-1β. Cell culture studies determined that Hcy caused macrophages to shift towards a destructive, M1 phenotype as indicated by elevated CD40, ROS, EMMPRIN and MMP-9 production. EMMPRIN inhibition prevented induction of CD40 and ROS. In CBS +/- mice, it was determined that HHcy causes increased elevations in F4/80 and TNF-α expression, which are indicative of M1 macrophages. Exercise was capable of reducing the M1 macrophage population. Conclusions: We conclude that HHcy causes skeletal muscle fibrosis through induction of MMP-9 and M1 macrophages. Exercise is capable of mitigating the pathologies associated with HHcy

Systemic and strength effects : experimental concentrations of topical menthol.

Menthol has been regularly utilized as a treatment in sports related injuries for many years, yet little is known about its physiological interactions or its effect on performance. Our previous study indicates that topically applied menthol may cause an acute decrease in blood flow and may improve strength capabilities. The purpose of this study is to examine the effects of two different concentrations of menthol (3.5% and 10%) on systemic blood flow and strength. 16 subjects participated in this 4 week study examining blood flow and strength effects after menthol or control treatment. Results indicate that the 3.5% menthol causes a significant (\u3c .05) decrease in blood flow, and arterial diameter in the treated leg, and decreased blood flow in the untreated leg. 10% menthol treatment attenuates the statistically significant increase in blood flow observed with Control treatment, and significantly decreases arterial diameter in the treated leg. Results indicate that menthol is capable of suppressing arterial blood flow locally and systemically

Comparison of the Effects of Ice and 3.5% Menthol Gel on Blood Flow and Muscle Strength of the Lower Arm

Context: Soft-tissue injuries are commonly treated with ice or menthol gels. Few studies have compared the effects of these treatments on blood flow and muscle strength. Objective: To compare blood flow and muscle strength in the forearm after an application of ice or menthol gel or no treatment. Design: Repeated measures design in which blood-flow and muscle-strength data were collected from subjects under 3 treatment conditions. Setting: Exercise physiology laboratory. Participants: 17 healthy adults with no impediment to the blood flow or strength in their right arm, recruited through word of mouth. Intervention: Three separate treatment conditions were randomly applied topically to the right forearm: no treatment, 0.5 kg of ice, or 3.5 mL of 3.5% menthol gel. To avoid injury ice was only applied for 20 min. Main Outcome Measures: At each data-collection session blood flow (mL/min) of the right radial artery was determined at baseline before any treatment and then at 5, 10, 15, and 20 min after treatment using Doppler ultrasound. Muscle strength was assessed as maximum isokinetic flexion and extension of the wrist at 30°/s 20, 25, and 30 min after treatment. Results: The menthol gel reduced (–42%, P \u3c .05) blood flow in the radial artery 5 min after application but not at 10, 15, or 20 min after application. Ice reduced (–48%, P \u3c .05) blood flow in the radial artery only after 20 min of application. After 15 min of the control condition blood flow increased (83%, P \u3c .05) from baseline measures. After the removal of ice, wrist-extension strength did not increase per repeated strength assessment as it did during the control condition (9–11%, P \u3c .05) and menthol-gel intervention (8%, P \u3c .05). Conclusions: Menthol has a fast-acting, short-lived effect of reducing blood flow. Ice reduces blood flow after a prolonged duration. Muscle strength appears to be inhibited after ice application

A comparative analysis of the exceptions/defences available under the Hague Convention on Civil Aspects of International Child Abduction, 1980 and their implementation and effectiveness in South Africa and Australia.

Thesis (LL.M.)-University of KwaZulu-Natal, 2011.No abstract provided

Cardiovascular responses during light-intensity aerobic exercise with varying levels of limb occlusion pressures.

International Journal of Exercise Science 16(2): 676-687, 2023. The study aimed to assess cardiovascular responses to low-intensity aerobic exercise with varying levels of limb occlusion pressures (LOP) in a healthy population of men and women 30 to 60 years. The study was a single-session repeated measures design. Thirty individuals completed the study. All subjects participated in a single bout of low-intensity cycling (30-39% HRR) with bilateral lower extremity (LE) BFR for four 5-minute stages [0% (No BFR), 40%, 60%, and 80% LOP] with a 2-minute active rest between stages (BFR pressure released). The subjects’ systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), oxygen saturation (SpO2), and ratings of perceived exertion (RPE) were measured at rest, peak, immediately post, post-15 minutes, and post-30 minutes. Peak SBP (no BFR 160.7 ±19.1 mmHg; 40% LOP 173.6 ± 18.7 mmHg; 60 % LOP; 182.5 ± 21.1 mmHg; 80% LOP 193.5± 23.3 mmHg ; p\u3c0.001; =.747), DBP (no BFR 74.9 ± 8.5 mmHg; 40% LOP (83.0 ± 9.0 mmHg;60 % LOP 90.4 ± 8.7 mmHg; 80% LOP 97.7 ± 9.5 mmHg ;p\u3c0.001; =.924), MAP (no BFR 103.5 ± 10.1 mmHg; 40% LOP 113.2 ± 10.5 mmHg; 60% LOP 121.1 ± 11.7 mmHg; 80% LOP 129.7 ± 12.9 mmHg; p\u3c0.001; =.960), and RPE (No BFR 10.0 ± 2.0; 40 % LOP 11.5 ± 2.3; 60% LOP 13.2 ± 2.6; 80% LOP 14.5 ± 3.; p\u3c0.001; =.826) were significantly higher with each progressing stage. The results indicate that low-intensity cycling with bilateral LE BFR for each LOP stage resulted in elevated SBP, DBP, MAP, and RPE despite maintaining a fixed HR

Effects of Varying Load Intensity on Skeletal Muscle Damage Between Two Isovolumic Resistance Exercise Bouts

International Journal of Exercise Science 15(4): 1212-1221, 2022. There are limited data comparing the efficacy of resistance loads within the hypertrophy range for promoting muscular growth, particularly when similar training volumes are utilized. The purpose of this study was to determine if two similar volume-loads, utilizing different intensities, would produce dissimilar muscular damage and inflammation. Eleven resistance-trained, college-aged males participated in this study. After testing 1RM barbell squats, participants completed two similar volume-load barbell squat sessions at two different resistance loads (67% and 85% of 1RM) on two separate visits. Venous blood samples were collected at baseline and one hour after completion of each exercise session. Plasma was isolated and analyzed for myoglobin and C-reactive protein (CRP) expression via ELISA. Plasma myoglobin expression was significantly elevated above baseline (BASE) values only after the 85% of 1RM (HHL) session (p =0.031), though the 67% (LHL) trial (p = 0.054; h2 = 0.647) was approaching significance (BASE: 1.42+.12 ng/mL; LHL: 4.65+1.13 ng/mL; HHL: 5.00+1.01 ng/mL). No changes in plasma CRP were observed. Despite attempts to equate volumes between resistances, mean total volume-load was significantly higher during the 67% of 1RM trial than during the 85% trial. Resistance loads at 85% of 1RM inflict significantly increased muscle damage over baseline values, even when significantly less total volume was lifted during the 85% trial. Individuals looking to maximize strength and hypertrophy during general training or during rehabilitation may benefit from these findings when determining the appropriate training load

Zinc oxide thin-film transistors fabricated at low temperature by chemical spray pyrolysis

We report the electrical behavior of undoped zinc oxide thin-film transistors (TFTs) fabricated by low-temperature chemical spray pyrolysis. An aerosol system utilizing aerodynamic focusing was used to deposit the ZnO. Polycrystalline films were subsequently formed by annealing at the relatively low temperature of 140°C. The saturation mobility of the TFTs was 2 cm2/Vs, which is the highest reported for undoped ZnO TFTs manufactured below 150°C. The devices also had an on/off ratio of 104 and a threshold voltage of −3.5 V. These values were found to depend reversibly on measurement conditions

Validity of smartphone heart rate variability pre- and post-resistance exercise

The aim was to examine the validity of heart rate variability (HRV) measurements from photoplethysmography (PPG) via a smartphone application pre- and post-resistance exercise (RE) and to examine the intraday and interday reliability of the smartphone PPG method. Thirty-one adults underwent two simultaneous ultrashort-term electrocardiograph (ECG) and PPG measurements followed by 1-repetition maximum testing for back squats, bench presses, and bent-over rows. The participants then performed RE, where simultaneous ultrashort-term ECG and PPG measurements were taken: two pre- and one post-exercise. The natural logarithm of the root mean square of successive normal-to-normal (R-R) differences (LnRMSSD) values were compared with paired-sampl

Area-wide distribution of lead, copper, and cadmium in air particulates from Chicago and northwest Indiana

Published air pollution emissions inventories for the urbanized and industrialized area along the southwestern shore of Lake Michigan include few chemical analyses of particulates, and estimates of the elemental composition of airborne solids may be made only indirectly and compared with NASN analyses from a few locations. As a first attempt to examine the area-wide distribution of specific chemical elements in this region, lead, copper, cadmium, and bismuth were determined in 24-h average samples collected on glass fiber filters at 50 stations throughout the region. Samples from most of the 50 stations were obtained from local air pollution control organizations for 6 different days from May to August 1968 and were analyzed electrochemically by highly sensitive anodic stripping voltammetry (ASV). Throughout the area the small variation of lead, generally a few micrograms per cubic meter of air, did not exceed that expected from the distribution of automobiles, the major source. Cadmium was generally 200 times lower without marked local variations and was close to the expected concentration if coal combustion is the major source. Copper was generally 20 times lower than lead throughout Chicago as expected if coal combustion is the major source of copper. However, certain stations in the northwest Indiana area showed reproducible anomalies where copper was 100 times greater than in Chicago and several times greater than lead at the same stations. The source of this anomalous copper has not been determined.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33563/1/0000064.pd

Impact of efavirenz pharmacokinetics and pharmacogenomics on neuropsychological performance in older HIV-infected patients

Pharmacokinetics (PK) and pharmacodynamics of efavirenz and its 8-hydroxy metabolite (8-OH-efavirenz) have not been robustly evaluated in older HIV-infected persons