Habitual aerobic exercise and smoking-associated arterial stiffening

textThe largest percentage of mortality from tobacco smoking is cardiovascular-related. It is not known whether regular participation in exercise mitigates the adverse influence of smoking on vasculature. The purpose of this study is to determine if regular aerobic exercise is associated with reduced arterial stiffness in young men who are cigarette smokers. Using a cross-sectional observational study design, the sample included 78 young men (22±5 years) with the following classification: sedentary smokers (n=12); physically active smokers (n=25); sedentary non-smokers (n=20); and physically active non-smokers (n=21). Arterial stiffness was assessed by brachial-ankle pulse wave velocity (baPWV). There were no group differences in height, body fatness, systolic and diastolic blood pressure. As expected, both physically active groups demonstrated greater VO2max and lower heart rate at rest than their sedentary peers. The sedentary smokers demonstrated greater baPWV than the sedentary non-smokers (1,183±33.5 vs. 1,055±25 cm/sec). baPWV was not different between the physically-active smokers and the physically-active non-smokers (1,084±26 vs. 1,070±28.6 cm/sec). Chronic smoking is associated with arterial stiffening in sedentary men but a significant smoking-induced increase in arterial stiffness was not observed in physically active adults. These results are consistent with the idea that regular participation in physical activity may mitigate the adverse effect of smoking on the vasculature.Kinesiology and Health Educatio

Accuracy of Various Newer Pedometers Placed at Different Body Sites

Introduction: Pedometers are increasingly used as a self-monitoring aid for achieving and increasing daily physical activity. Older pedometers had varied levels of accuracy ranging from 0 to 45% difference and were needed to be positioned in a certain way (on the waist). Newer models can be placed anywhere on the body but its accuracy is unknown when they are placed at different bodily sites. Purpose: We determined the accuracy of various newer pedometers under controlled laboratory and free walking conditions. Method: A total of 40 subjects (20 male and 20 female) varying widely in age (18-61 years) and BMI (18-38 kg/m²) were studied. The pedometers, including Omron HJ-320BULK, Omron HJ-324U, Life Source XI-25, Fitbit Ultra, and Virgin Health Miles, were placed at waist, at chest, in a pocket, and on an armband. The number of steps recorded with the pedometers was compared against those counted with a hand tally counter while the subjects walked on the treadmill at 54, 80, 107, 134, and 161 m/min and on paved ground outside at a self-selected pace. Results: Overall, all pedometers displayed values that were within 9% of actual steps in all conditions when they were placed at waist, chest, and armband. However, when they were placed in a pocket, step counts deviated significantly from the hand counts by \u3e 11% in some models (Life Source, Fitbit, and Virgin Health) (PConclusions:All the pedometers examined were accurate when they were placed at waist, chest, and armband no matter what walking speed or what terrain they exercised. But some pedometers did not register accuracy when they were put in the pocket

Effect of walking speed and placement position interactions in determining the accuracy of various newer pedometers

AbstractOlder types of pedometers had varied levels of accuracy, which ranged from 0% to 45%. In addition, to obtain accurate results, it was also necessary to position them in a certain way. By contrast, newer models can be placed anywhere on the body; however, their accuracy is unknown when they are placed at different body sites. We determined the accuracy of various newer pedometers under controlled laboratory and free walking conditions. A total of 40 participants, who varied widely in age and body mass index, were recruited for the study. The numbers of steps recorded using five different pedometers placed at the waist, the chest, in a pocket, and on an armband were compared against those counted with a hand tally counter. With the exception of one, all the pedometers were accurate at moderate walking speeds, irrespective of their placement on the body. However, the accuracy tended to decrease at slower and faster walking speeds, especially when the pedometers were worn in the pockets or kept in the purse (p < 0.05). In conclusion, most pedometers examined were accurate when they were placed at the waist, chest, and armband irrespective of the walking speed or terrain. However, some pedometers had reduced accuracy when they were kept in a pocket or placed in a purse, especially at a slower and faster walking speeds

Therapeutic Sources of Skeletal Muscle Regeneration from Volumetric Muscle Loss: A Narrative Review

PURPOSE Minor skeletal muscle injuries can be repaired, but more extensive volumetric muscle loss (VML) leads to a permanent functional disability with ambiguous therapeutic outcomes, and reconstructive surgical procedures are constrained by donor tissue scarcity. This review assessed the considerable attention paid to biomaterials in healing damaged skeletal muscle. METHODS A comprehensive search in PubMed, Web of Science, Google Scholar, and Wiley Online Library was conducted to obtain previous studies exploring the state of biocompatible tissue scaffolds for VML recovery. RESULTS By regenerating the function of damaged skeletal muscle, tissue-engineered skeletal muscle construction could revolutionize the treatment of VML. However, transporting cells into the wounded muscle location presents a significant challenge because it may result in unfavorable immunological reactions. The development and validation of several biomaterials with varying physical and chemical natures to treat various muscle injuries have recently been undertaken to overcome this problem. This review discusses the relative benefits of satellite cells (SC), the most prevalent skeletal muscle stem cells employed to seed scaffolds. CONCLUSIONS Biomaterials can be used with skeletal muscle stem cells and growth factors to repair VML because of their customizable and desirable physicochemical qualities. Owing to the capacity of SCs for self-renewal and their undifferentiated state, these cells are excellent candidates for cell therapy. A large gap exists between understanding SC behavior and how it can be used to repair and regenerate human skeletal muscle tissue. Thus, this review sought to portray the current knowledge on the lifespan of SCs and their involvement in exercise-induced muscle regeneration and hypertrophy

Changes in Arterial Stiffness and Blood Pressure during Various Vascular Reactivity Tests

Increased arterial stiffness is an independent prognosis marker of elevated cardiovascular risks. However, some investigators have questioned the utility of arterial stiffness above and beyond the traditional blood pressure (BP) measurement as the change in arterial stiffness is often accompanied by the corresponding change in BP. Although the associations between chronic levels of arterial stiffness and BP have been fairly well studied, it is not clear if and how much arterial stiffness is influenced by acute changes in BP. PURPOSE: We determined magnitudes of BP-dependence of arterial stiffness during acute BP perturbations. METHODS: Thirty apparently healthy subjects (46±4 years; 17 males & 13 females) were studied. A variety of BP perturbations, including head-up tilt, head-down tilt, mental stress, isometric handgrip exercise, and cold pressor test were used in order to encompass blood pressure changes induced by physical, mental, and/or physiological stimuli. Arterial stiffness was measured with carotid-femoral pulse wave velocity (PWV). RESULTS: PWV was significantly associated with mean BP at rest (r=0.42). Mean BP was significantly changed during each of the BP perturbations, and changes in mean BP ranged from △5±4 to △22±4 mmHg. Changes in mean BP and PWV were significantly correlated during mental stress (r=0.44), handgrip exercise (r=0.55), and cold pressor test (r=0.39). But no such significant associations were found during head-up tilt and head-down tilt. CONCLUSION: This study demonstrated that changes in arterial stiffness as assessed by PWV were significantly associated with acute blood pressure changes during some blood pressure perturbations. But the blood pressure-dependence of arterial stiffness was not observed in all the perturbations

Processing Negative Polarity Items in Korean: Implications from an ERP Study

The present study used event-related potentials (ERPs) to examine the neural correlates supporting the processing of two negative polarity items (NPI) (nominal amwu+N+to any+N+even and adverbial te isang any more/longer) in Korean. Participants read sentences phrase by phrase while their brain activities during the processing of the NPIs and their licensors were being recorded. The results revealed that the NPI licensors in such contexts as positive or interrogative clauses not containing a proper licensor elicited a larger N400 component, possibly reflecting the cost of semantic or pragmatic integration. By contrast, sentences with the adverbial NPI te isang in the negative implicatureinducing before clause are not significantly different in ERP responses from those in the negative clause, thus evoking no ERP component. The present findings not only demonstrate semantic and pragmatic effects in neural signatures evoked by varied NPI-licensor relations, but also point to the multidimensionality of NPI processing/licensing recruiting semantic/pragmatic integration as well as syntactic dependency formation.We are grateful to the three anonymous reviewers of this journal for the helpful comments and suggestions. Usual disclaimers apply here, of course. This work was supported by the Ministry of Education of the Republic of Korea and the National Research Foundation of Korea (NRF2015S1A5A2A03048485

Implantation of Decellularized Extracellular Matrix with Resistance Training Effectively Repairs a Volumetric Muscle Loss

PURPOSE Skeletal muscle has remarkable regenerative capacity in most minor injuries induced by mechanical laceration, overstretching, and toxins. However, volumetric muscle loss (VML) injury, a large volume of muscle loss beyond the self-repair capacity, causes functional disability and morphological deformities. This study investigated the effects of myofiber injection into a decellularized extracellular matrix (ECM) and resistance training (RT) on skeletal muscle regeneration following VML injury. METHODS 6-months-old male Fischer CDF rats and 2-months-old F344-Tg (UBC-EGFP) rats (myofiber donors) were used in this study. Approximately 20% of the mass of the lateral gastrocnemius (LGAS) was excised and replaced by ECM of similar dimensions. Thirty myofibers were injected into the injured region seven days post-injury. Ladder climbing (RT) was allowed 10 days post-defect surgery, and the rats were subjected to ladder climbing with a weight every third day for 6 weeks. RESULTS After 56 days of recovery and exercise training, the cross-sectional area (CSA) of intact muscle in the EXE group (5,104±92 μm2) increased significantly compared to that in the ECM (4,657±79 μm2) group. The number of blood vessels larger than 20 μm in diameter, capillaries excluded, showed a significant difference between the ECM+EXE (34.25±4.2) and ECM (21.75±3.89) groups. A significant reduction of fibrosis in the ECM+EXE (44.50±1.6%) group was observed compared to the ECM (69.25±1.9%) and ECM+FIB+EXE (63.00±1.7%) groups. Moreover, the small muscle fiber area within the transplanted ECM was significantly larger in the ECM+EXE (1.37±0.03 mm2) than in both the ECM (0.49±0.01 mm2) and ECM+FIB (0.62±0.01 mm2) groups. CONCLUSIONS These data suggest that ECM transplantation with RT effectively repairs VML by enhancing hypertrophy, angiogenesis, and myofiber infiltration throughout the entire ECM

A Statistical Verification Method of Random Permutations for Hiding Countermeasure Against Side-Channel Attacks

As NIST is putting the final touches on the standardization of PQC (Post Quantum Cryptography) public key algorithms, it is a racing certainty that peskier cryptographic attacks undeterred by those new PQC algorithms will surface. Such a trend in turn will prompt more follow-up studies of attacks and countermeasures. As things stand, from the attackers' perspective, one viable form of attack that can be implemented thereupon is the so-called "side-channel attack". Two best-known countermeasures heralded to be durable against side-channel attacks are: "masking" and "hiding". In that dichotomous picture, of particular note are successful single-trace attacks on some of the NIST's PQC then-candidates, which worked to the detriment of the former: "masking". In this paper, we cast an eye over the latter: "hiding". Hiding proves to be durable against both side-channel attacks and another equally robust type of attacks called "fault injection attacks", and hence is deemed an auspicious countermeasure to be implemented. Mathematically, the hiding method is fundamentally based on random permutations. There has been a cornucopia of studies on generating random permutations. However, those are not tied to implementation of the hiding method. In this paper, we propose a reliable and efficient verification of permutation implementation, through employing Fisher-Yates' shuffling method. We introduce the concept of an n-th order permutation and explain how it can be used to verify that our implementation is more efficient than its previous-gen counterparts for hiding countermeasures.Comment: 29 pages, 6 figure

Impact of Cigarette Smoking and Exercise on Arterial Stiffness: A Narrative Literature Review

PURPOSE Smoking often causes acute and chronic cardiovascular disorders. Cigarette smoking increases oxidative stress, reduces nitric oxide bioavailability, and changes the extracellular matrix, impairing arterial stiffness. However, regular physical activity and smoking cessation significantly and rapidly reverse the detrimental effects. This narrative review summarizes the relevant research that describes the impacts of cigarette smoking on the cardiovascular system and demonstrates the therapeutic or preventative roles of exercise and smoking cessation in smoking-associated arterial stiffness. METHODS We used scientific search engines, including PubMed, Web of Science, Google Scholar, and Wiley Online Library, to identify previous studies exploring the effects of smoking, exercise, and smoking cessation on arterial stiffness. RESULTS We discussed the most important therapeutic and/or preventive roles of exercise and smoking cessation in decreasing arterial stiffness. Most studies have demonstrated that acute and chronic smoking increase arterial stiffness. Smoking and physical activity were negatively associated. However, this relationship was often attenuated or reversed during adult exercise interventions. In addition, smoking cessation reversed the effects of smoking on arterial stiffness. CONCLUSIONS Smoking increases the risk of acute and chronic cardiovascular disease. Cigarette smoking deteriorates arterial stiffness by altering the vascular walls. However, regular exercise and smoking cessation can improve or prevent impaired arterial stiffness