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Hsu, CC, Fong, TH, Chang, HM, Su, B, Chi, CP, Kan, NW, and Hsu, MC. Low second-to-fourth digit ratio has high explosive power? A prepubertal study. J Strength Cond Res 32(7): 2091-2095, 2018-A recent study reported that lower limb explosive power had no correlation with the index finger: ring finger (2D:4D) ratio. However, many studies hypothesized that a lower 2D:4D ratio (reflecting a relative higher testosterone exposure) predicts higher physical fitness. The aim of this study was to replicate the study of explosive power and the 2D:4D ratio in a sample of Taiwanese children. A total of 541 Taiwanese prepubertal children (257 girls and 284 boys aged 9-10 years) participated in this study. This study analyzed the relationship between the 2D:4D ratio and explosive power. Explosive power of the lower limbs was assessed using the standing long jump (SLJ) test. The lengths of the second and fourth fingers of the right hand were measured to calculate the 2D:4D ratio. The SLJ length was correlated with the 2D:4D ratios (r = -0.144, p = 0.015) in boys. After controlling for age and the body mass index, this correlation remained significant (r = -0.134, p = 0.024). For girls, 2D:4D ratios were not significantly correlated with SLJ scores. These results indicate that the SLJ distance was negatively correlated with the 2D:4D ratio in boys, but not in girls. These findings might suggest that prenatal testosterone exposure is negatively correlated with the explosive power in men, but not in women.

In this study we used the poly(N-isopropylacrylamide) (PNIPAAm) as a medium to blend with an organic DNA, herring sperm DNA (HSD), to generate PNIPAAm-HSD supramolecular complexes. Bio-multiple hydrogen bonding (BMHB) between PNIPAAm and HSD was investigated that changed the temperature responsiveness of PNIPAAm relatively to the HSD concentrations. With blending the HSD into PNIPAAm matrix, the phase separation in solution is completely opposite from that of neat PNIPAAm. Surface property in static water contact angle (SWCA) is also opposite from that of pure PNIPAAm upon increasing HSD content over 60%. In addition, we found that the PNIPAAm and HSD self-assembled a specific triangle-like structure at a PNIPAAm-to-HSD weight ratio of 1:4 at 25°C; while the triangle-like structure disappeared with increasing temperature to 45°C. Furthermore, both PNIPAAm and HSD could be regarded as insulator, but it transformed into a semiconductive matter after blending with the HSD. Incorporation of organic DNA with hydrogel could significantly change their properties, which might facilitate their use as novel materials in bioelectronics.

Electrospun polyacrylonitrile fiber membranes (EPFMs) were coated with multilayer films, assembled using the layer-by-layer (LbL) technique through the alternate deposition of poly(allylamine hydrochloride) (PAH) and poly(acrylic acid) (PAA), to develop an antithrombogenic drug release membrane for hemodialysis. Methylene blue (MB) and heparin (HEP) were attached to the PAH and PAA multilayers, respectively, as model drug and antithrombogenic agent to investigate the dual functionality of the membranes. The positively (PAH, MB) and negatively (PAA, HEP) charged groups generated a supermolecular polyelectrolyte multilayer film (SPF) capable of loading high amounts of MB and HEP on the EPFMs at appropriate composition. The pH was fixed at 5.5 during assembly to stabilize the SPF. Heavy assembly of the PAH/PAA multilayer occurred at 10 wt% of both MB and HEP with 25 cycles of LbL deposition, and it exhibited long-term release of MB and low release of HEP at pH 7.4 in a circulatory system. The SPF-coated EPFMs also achieved low platelet attachment after 4 h of platelet rich plasma circulation and showed prolonged clotting times including thromboplastin, thrombin, and prothrombin times. Collectively, these observations suggest that SPF-coated EPFMs have great potential for use as hemodialysis membranes with positively charged drug loading.

Several studies have compared molecular components between red and white skeletal muscles in mammals. However, mammalian skeletal muscles are composed of mixed types of muscle fibers. In the current study, we analyzed and compared the distributions of titin, lipid, phosphate ions, and fatty acid levels in red and white muscles using a fish model (Tilapia), which is rich in red and white muscles, and these are well separated. Oil-red O staining showed that red muscle had more-abundant lipids than did white muscle. A time-of-flight secondary-ion mass spectrometric (TOF-SIMS) analysis revealed that red muscle possessed high levels of palmitic acid and oleic acid, but white muscle contained more phosphate ions. Moreover, elastica-van Gieson (EVG) and Mito-Tracker green FM staining showed that collagen and elastic fibers were highly, respectively, distributed in connective tissues and mitochondria in red muscle. An electron micrographic analysis indicated that red muscle had a relatively higher number of mitochondria and longer sarcomere lengths and Z-line widths, while myofibril diameters were thicker in white muscle. Myofibrillar proteins separated by SDS-PAGE showed that the major giant protein, titin, was highly expressed in white muscle than in red muscle. Furthermore, ratios of titin to myosin heavy chain (MHC) (titin/MHC) were about 1.3 times higher in white muscle than red muscle. We postulated that white muscle is fit for short and strong contractile performance due to high levels of titin and condensed sarcomeres, whereas red muscle is fit for low intensity and long-lasting activity due to high levels of lipids and mitochondria and long sarcomeres.

LANGUAGE NOTE | Document text in English; abstract also in Chinese. The purpose of this study was to understand the current usage of nutritional supplements in Taiwan elite athletes. This study adopting purposive sampling, we surveyed 105 male and 80 female athletes across sports selected for doping control at the National Athletic Games during year 2007 in Taiwan to understand the athletes’ use of nutritional supplements 14 days prior to the games. Categories of nutritional supplements include vitamin/mineral supplements, amino acid supplements, instant energy supplements, healthcare foods, and drinks. The results indicated 88.1% of the athletes have used nutritional supplements. The usage rates for different categories of nutritional supplements were vitamin/mineral supplements (48.1%), drinks (45.9%), healthcare foods (39.5%), amino acid supplements (31.9%), and instant energy supplements (24.9%). Female athletes had a higher tendency to use vitamin/mineral supplements (55.0% vs. 42.9%) and healthcare foods (47.5% vs. 33.3%) compared to male athletes. Among the sports, weightlifters/bodybuilders and swimmers have all used nutritional supplements (100%), especially the use of creatine for the weightlifters/bodybuilders (69.7%) and multivitamin (76.2%) for the swimmers. In addition, the most consumed types in different categories of nutritional supplements were multivitamins (37.3%) for vitamin/ mineral supplements, creatine (26.5%) for amino acid supplements, chocolate (15.1%) for instant energy supplements, Cordymax Cs-4 Capsules (16.2%) for healthcare foods, and sports drinks (42.4%) for drinks. In conclusion, the results on the current use of nutritional supplements for Taiwan elite athletes could act as a reference to coaches, athletes and sports organizations. 本研究目的在於了解台灣優秀選手使用營養增補劑的現況。本研究採立意抽樣，我們調查了2007年全國運動會(全運會) 期間，105 名男性以及 80 名女性需接受運動禁藥抽檢之選手，以了解其比賽前14天使用營養增補劑的情形。營養增補劑種類包括：維生素/礦物質、胺基酸補給品、即時能量補給品、保健食品，以及飲料類。本研究結果顯示88.1%的運動員有使用營養增補劑。不同種類的營養增補劑中，選手使用率分別為維生素/礦物質 (48.1%)；飲料 (45.9%)；保健食品 (39.5%)；胺基酸補給品 (31.9%)；即時能量補給品 (24.9%)。相較於男性選手，女性選手在維生素/礦物質 (55.0% vs. 42.9%) 與保健食品 (47.5% vs. 33.3%) 的使用率有較高的趨勢。在所有的運動項目中，舉重/健美以及游泳選手營養增補劑的使用率為100%，特別是舉重/健美選手對肌酸 (69.7%)，以及游泳選手對綜合維生素 (76.2%)有較高的使用率。此外，不同種類的營養增補劑中，選手最常使用的分別為維生素/礦物質之綜合維生素 (37.3%)；胺基酸補給品之肌酸 (26.5%)；即時能量補給品之巧克力 (15.1%)；保健食品類之動能食物膠囊 (16.2%)；飲料類之運動飲料 (42.4%)。本研究對台灣優秀選手使用增補劑的現況之結果可作為教練、選手以及各級運動團體之參考。

We compared the lower limb muscle activation during uphill running (UR), level running (LR), and downhill running (DR). Eight male physically active subjects ran three slopes for 30 min at the given speed (55% vVO2peak at LR), including DR ( 6 � ), LR (0 � ), and UR (6 � ) in a random crossover, repeated measures design. Electromyographic (EMG) signals were collected from the dominated lower limb muscles: rectus femoris (RF), biceps femoris (BF), gastrocnemius (GAS), soleus, and tibialis anterior. Our results showed that greater EMG of RF was found with inclining slope (UR>LR>DR, p DR>LR (p < 0.05). We concluded that significant differences regarding muscle activations among DR, LR, and UR were observed for the RF, BF, and GAS, especially when running opposing slopes (DR vs. UR). Additionally, when running toward uphill, the propulsive muscles, such as the RF and GAS seemed to exert more effort. In contrast, while running toward downhill, RF might work as an extensor muscle that was activated to a lesser extent, possi bly due to its undergoing eccentric movement.

Background Angelica Sinensis (AS), a folk medicine, has long been used in ergogenic aids for athletes, but there is little scientific evidence supporting its effects. We investigated whether AS induces hypertrophy in myotubes through the phosphatidylinositol 3-kinase (PI3K)/Akt (also termed PKB)/mammalian target of the rapamycin (mTOR) pathway. Methods An in vitro experiment investigating the induction of hypertrophy in myotubes was conducted. To investigate whether AS promoted the hypertrophy of myotubes, an established in vitro model of myotube hypertrophy with and without AS was used and examined using microscopic images. The role of the PI3K/Akt/mTOR signaling pathway in AS-induced myotube hypertrophy was evaluated. Two inhibitors, wortmannin (an inhibitor of PI3K) and rapamycin (an inhibitor of mTOR), were used. Result The results revealed that the myotube diameters in the AS-treated group were significantly larger than those in the untreated control group (P

Lipid metabolism in visceral fat cells is correlated with metabolic syndrome and cardiovascular diseases. Okadaic-acid, a 38-carbon fatty acid isolated from the black spongeHalichondria okadai, can stimulate lipolysis by promoting the phosphorylation of several proteins in adipocytes. However, the mechanism of okadaic acid-induced lipolysis and the effects of okadaic acid on lipid-droplet-associated proteins (perilipins and beta-actin) remain unclear. We isolated adipocytes from rat epididymal fat pads and treated them with isoproterenol and/or okadaic acid to estimate lipolysis by measuring glycerol release. Incubating adipocytes with okadaic acid stimulated time-dependent lipolysis. Lipid-droplet-associated perilipins and beta-actin were analyzed by immunoblotting and immunofluorescence, and the association of perilipin A and B was found to be decreased in response to isoproterenol or okadaic acid treatment. Moreover, okadaic-acid treatment could enhance isoproterenol-mediated lipolysis, whereas treatment of several inhibitors such as KT-5720 (PKA inhibitor), calphostin C (PKC inhibitor), or KT-5823 (PKG inhibitor) did not attenuate okadaic-acid-induced lipolysis. By contrast, vanadyl acetylacetonate (tyrosine phosphatase inhibitor) blocked okadaic-acid-dependent lipolysis. These results suggest that okadaic acid induces the phosphorylation and detachment of lipid-droplet-associated perilipin A and B from the lipid droplet surface and thereby leads to accelerated lipolysis.

This study investigated the effects of BCAA, arginine and carbohydrate combined beverage (BCAA Drink) on biochemical responses and psychological conditions during recovery after a single bout of exhaustive exercise. Fourteen healthy males were assigned to drink either BCAA Drink (BA trial) or placebo (PL trial) on two sessions separated by 2 weeks. Blood samples of each subject were collected before exercise, 0, 10, 20, 40, 60, 120 min and 24 h after exercise. No significant differences in the levels of lactate, ammonia, creatine kinase and glycerol between the two groups were observed at any of the time points. However, the levels of glucose and insulin were significantly higher in the BA trial as compared to those in the PL trial at the 40 and 60 min recovery points. Furthermore, the testosterone-to-cortisol ratio at the 120 min recovery point was significantly higher in the BA trial as compared to that in the PL trial. The results indicate the occurrence of anabolic response during the recovery period. The benefit of BCAA Drink was also performed by Profile of Mood States to assess the psychological condition. Fatigue score increased immediately at exhaustion in both groups, but the decrease in the fatigue score at 120 min recovery point was significant only in BA trial. These data indicate that a single bout of exhaustive exercise enhanced the feeling of fatigue. The detrimental consequence was reduced by an ingestion of BCAA Drink.

Digit ratio (second to fourth or 2D:4D) is related to the concentration of prenatal androgens. Testosterone affected fetal brain and body development; digit ratio varied due to sexual dimorphism, and exhibited correlations to athletic prowess and behavior. We investigated the sexual dimorphism of college students' digit ratio in Taiwan, and understood the correlation between digit ratio and other different fitness indicators, as well as sports participation behaviors. Additionally, we compared the digit ratio in different levels of sports participators. Total 813 college students (338 males, 475 females, aged 18-19 years) were participated in this study. Subjects were measured based on fitness and asked to complete surveys on sports participation behavior. Digit ratio was analyzed using a scanning method. Digit ratio of male subjects ( .955 ± .028) was significantly (p＜.01) lower than female subjects ( .971 ± .031). As for athletic prowess of all subjects, muscle strength (handgrip strength and leg pressing), muscular endurance (sit-ups per minute) and cardiopulmonary fitness (Harvard step test) displayed a negative correlation with digit ratio of both hands (p ＜ .05). As for sports participation of all subjects, left hand digit ratio displayed a negative correlation with exercise habits (r=-.13, p ＜ .01) and accumulated exercise time per week (r=-.13, p ＜ .05). We distinguished two groups by gender, which only male group cardiopulmonary fitness and accumulated exercise time per week showed a negative correlation with left hand digit ratio, while female digit ratio didn’t showed correlation with any fitness and sports participation indicators. Left hand digit ratio of male and female members of school sports teams, which had higher athletic training frequency was significantly lower than members of non-school sports teams. Our results indicated that digit ratio might affect subsequent levels of sports participation. Male groups with lower digit ratio exhibited higher levels of sports participation behavior, therefore, resulted in better cardiopulmonary fitness.

This study aims to understand the effect of ten-week passive repetitive plyometric (PRP) training on human skeletal muscle and the application of PRP training for performance. Vastus lateralis of nine candidates were aspirated before (pre) and after (post) PRP training. Histochemical approaches with regular hematoxylene-eosin (HE) and Mallory's phosphotungstic acid hematoxylin (PTAH) stains were used to demonstrate the changes of muscle fibers. Immunohistochemical studies with heat shock protein (anti-hsp72, Stressgen, Canada) were employed to display cellular activities. Each set of slides was quantitatively analyzed by using a modified morphometric method (Russ and Dehoff, 1999) on a Nikon ECLIPSE 80i microscope, equipped with an Evolution VF COOLED color video camera, and the Image-Pro Plus software (5.0 for Win; Media Cybernetics, USA). Finally, hsp72 mRNAs of both pre-PRP and post-PRP specimens were amplified through RT-PCR. Signal intensities were read by a densitometer and analyzed through the SPSS (11.0 for Win) statistically. Post-PRP muscle cells demonstrated hypertrophic change with increased cellular content and a narrowed inter-cellular space according to both HE and PTAH profiles. Post-PRP cellular hsp72 proteins were higher by up to five percent, as measured by a gray-scale reading. Further, after a training period of 10 weeks, hsp72 mRNA expression was several times higher.

AIM: To investigate whether American ginseng (AG, Panax quinquefolium) supplementation was able to improve endurance exercise performance. METHODS: Thirteen physically active male college students were divided into two groups (AG or placebo) and received supplementation for 4 wk, before the exhaustive running exercise. Treadmill speed was increased to a pace equivalent to 80% VO2max of the subject. A 4-wk washout period followed before the subjects crossed over and received the alternate supplement for the next 4 wk. They then completed a second exhaustive running exercise. The physiological variables that were examined included time to exhaustion and oxygen pulse. Moreover, the plasma creatine kinase (CK) and lactate were measured prior to the exercise, at 15 and 30 min during exercise, immediately after exercise, and 20, 40, 60, and 120 min after exercise. RESULTS: The major finding of this investigation was that the production plasma CK during the exercise significantly decreased for group AG than for group P. Secondary physiological finding was that 80% VO2max running was not improved over a 4-wk AG supplementation regimen. CONCLUSION: Supplementation with AG for 4 wk prior to an exhaustive aerobic treadmill running reduced the leakage of CK during exercise, but did not enhance aerobic work capacity. The reduction of plasma CK may be due to the fact that AG is effective for the decrease of skeletal muscle cell membrane damage, induced by exercise during the high-intensity treadmill run.

To investigate whether exogenous surfactant would improve gas exchange and lung histology and methylprednisolone pretreatment would enhance the surfactant effect in a rat model of paraquat-induced lung injury.University research facility.Thirty-three adult male Sprague-Dawley rats.All rats received intraperitoneal paraquat injection (35 mg/kg) and were assigned randomly to one of four groups: the control group received no further treatment; the methylprednisolone group received a concomitant intraperitoneal methylprednisolone injection (30 mg/kg); the surfactant group received intratracheal Survanta (100 mg/kg) at the start of ventilation; and the methylprednisolone + surfactant group received both methylprednisolone and surfactant treatments.Three days after paraquat injection, every rat was ventilated for 90 min, a static pressure-volume curve and bronchoalveolar lavage were performed and postmortem histology was examined. Treatment with surfactant and methylprednisolone + surfactant improved oxygenation relative to the control group and produced significantly higher lung volumes than the control and methylprednisolone groups. Treatment with surfactant resulted in a significant decrease in total cell and neutrophil counts relative to the control group. Surfactant with methylprednisolone pretreatment significantly decreased total cell, macrophage and neutrophil counts when compared with the surfactant group. The histological appearance of the lungs was better in the two surfactant-treated groups.Intratracheal instillation of surfactant improves gas exchange, ameliorates lung inflammation and results in less lung damage in paraquat-induced rat lung injury. Surfactant with methylprednisolone pretreatment decreases inflammatory cell infiltration, but cannot further improve oxygenation and lung histology.