The association between different impact exercises and osteoporosis: an analysis of data from the Taiwan biobank.

Osteoporosis is a prevalent condition marked by reduced bone density and an elevated risk of fractures, especially among postmenopausal women. Exercise plays a crucial role in preventing and managing osteoporosis, with weight-bearing and impact exercises being particularly effective in enhancing bone density and mitigating disease risk. This study investigated the relationship between various types of impact exercises and osteoporosis using data from the Taiwan Biobank (TWB). The study sample comprised 5,123 individuals without osteoporosis and 1,770 individuals with the condition. Student's t-test and logistic regression analyses were utilized to assess the associations between exercise types and osteoporosis risk. Results indicated that high-impact exercise significantly reduced the likelihood of developing osteoporosis compared to no exercise (odds ratio; OR = 0.573, 95% CI: 0.406-0.810, P = 0.002). Conversely, low-impact exercises did not show a significant overall association with osteoporosis (OR = 1.160, 95% CI: 0.932-1.445, P = 0.184). Stratified analysis by sex revealed that high-impact exercise was protective against osteoporosis in men (OR = 0.391, 95% CI: 0.202-0.755, P = 0.005), but not significantly so in women (OR = 0.671, 95% CI: 0.438-1.027, P = 0.066). These findings suggest that high-impact exercise is associated with a reduced risk of osteoporosis, particularly among Taiwanese men aged 30 to 70.

Origin of Limiting and Overlimiting Currents in Bipolar Membranes.

Bipolar membranes (BPMs), a special class of ion exchange membranes with the unique ability to electrochemically induce either water dissociation or recombination, are of growing interest for environmental applications including eliminating chemical dosage for pH adjustment, resource recovery, valorization of brines, and carbon capture. However, ion transport within BPMs, and particularly at its junction, has remained poorly understood. This work aims to theoretically and experimentally investigate ion transport in BPMs under both reverse and forward bias operation modes, taking into account the production or recombination of H+ and OH-, as well as the transport of salt ions (e.g., Na+, Cl-) inside the membrane. We adopt a model based on the Nernst-Planck theory, that requires only three input parameters─membrane thickness, its charge density, and pK of proton adsorption─to predict the concentration profiles of four ions (H+, OH-, Na+, and Cl-) inside the membrane and the resulting current-voltage curve. The model can predict most of the experimental results measured with a commercial BPM, including the observation of limiting and overlimiting currents, which emerge due to particular concentration profiles that develop inside the BPM. This work provides new insights into the physical phenomena in BPMs and helps identify optimal operating conditions for future environmental applications.

Near-perfect kinetic resolution of o-methylphenyl glycidyl ether by RpEH, a novel epoxide hydrolase from Rhodotorula paludigena JNU001 with high stereoselectivity.

In order to provide more alternative epoxide hydrolases for industrial production, a novel cDNA gene Rpeh-encoding epoxide hydrolase (RpEH) of Rhodotorula paludigena JNU001 identified by 26S rDNA sequence analysis was amplified by RT-PCR. The open-reading frame (ORF) of Rpeh was 1236 bp encoding RpEH of 411 amino acids and was heterologously expressed in Escherichia coli BL21(DE3). The substrate spectrum of expressed RpEH showed that the transformant E. coli/Rpeh had excellent enantioselectivity to 2a, 3a, and 5a-10a, among which E. coli/Rpeh had the highest activity (2473 U/g wet cells) and wonderful enantioselectivity (E = 101) for 8a, and its regioselectivity coefficients, αR and ßS, toward (R)- and (S)-8a were 99.7 and 83.2%, respectively. Using only 10 mg wet cells/mL of E. coli/Rpeh, the near-perfect kinetic resolution of rac-8a at a high concentration (1000 mM) was achieved within 2.5 h, giving (R)-8a with more than 99% enantiomeric excess (ees) and 46.7% yield and producing (S)-8b with 93.2% eep and 51.4% yield with high space-time yield (STY) for (R)-8a and (S)-8b were 30.6 and 37.3 g/L/h.

Substantially improving the enantioconvergence of PvEH1, a Phaseolus vulgaris epoxide hydrolase, towards m-chlorostyrene oxide by laboratory evolution.

BACKGROUND: Epoxide hydrolase can regioselectively catalyze the oxirane ring-opening hydrolysis of rac-epoxides producing the corresponding chiral diols. In our laboratory, a gene named pveh1 encoding an EH from Phaseolus vulgaris was cloned. Although the directed modification of PvEH1 was carried out, the mutant PvEH1Y3 showed a limited degree of enantioconvergence towards racemic (rac-) m-chlorostyrene oxide (mCSO). RESULTS: PvEH1 and PvEH1Y3 were combinatively subjected to laboratory evolution to further enhance the enantioconvergence of PvEH1Y3 towards rac-mCSO. Firstly, the substrate-binding pocket of PvEH1 was identified using a CAVER 3.0 software, and divided into three zones. After all residues in zones 1 and 3 were subjected to leucine scanning, two E. coli transformants, E. coli/pveh1Y149L and /pveh1P184L, were selected, by which rac-mCSO was transformed into (R)-m-chlorophenyl-1,2-ethanediol (mCPED) having 55.1% and 27.2% eep. Secondly, two saturation mutagenesis libraries, E. coli/pveh1Y149X and /pveh1P184X (X: any one of 20 residues) were created at sites Y149 and P184 of PvEH1. Among all transformants, both E. coli/pveh1Y149L (65.8% αS and 55.1% eep) and /pveh1P184W (66.6% αS and 59.8% eep) possessed the highest enantioconvergences. Finally, the combinatorial mutagenesis was conducted by replacements of both Y149L and P184W in PvEH1Y3, constructing E. coli/pveh1Y3Z2, whose αS reached 97.5%, higher than that (75.3%) of E. coli/pveh1Y3. In addition, the enantioconvergent hydrolysis of 20 mM rac-mCSO was performed by E. coli/pveh1Y3Z2, giving (R)-mCPED with 95.2% eep and 97.2% yield. CONCLUSIONS: In summary, the enantioconvergence of PvEH1Y3Z2 was successfully improved by laboratory evolution, which was based on the study of substrate-binding pocket by leucine scanning. Our present work introduced an effective strategy for the directed modification of enantioconvergence of PvEH1.

Exercise might prevent cirrhosis in overweight and obese adults.

BACKGROUND & AIMS: Exercise in overweight patients with liver disease has improved liver enzymes, insulin levels and quality of life. Scientific evidence is incomplete regarding the role of exercise in the prevention of cirrhosis. We investigated the effect of exercise on the occurrence of cirrhosis in obese and overweight adults. METHODS: Exercise was assessed using the 2012 Adult Preventive Medical Service dataset while cirrhosis was identified using the National Health Insurance Research Database. All participants were aged 40 years and older. Unconditional logistic regression was used to estimate the odds ratios for cirrhosis. RESULTS: Overall, 1586 overweight and 1525 obese adults were identified with cirrhosis. Weekly exercise >150 min was significantly protective for cirrhosis in obese men and women. However, exercise <150 min/wk was significantly protective only in men compared to women. For weekly exercise >150 mins, the odds ratio for cirrhosis in obese men and women was 0.701 (95% CI: 0.584-0.841) and 0.736 (95% CI: 0.562-0.964) respectively. The adjusted odds ratios in overweight men and women were 0.734 (95% CI: 0.622-0.866) and 0.503 (CI: 0.37-0.684). For weekly exercise <150 min/wk, overweight and obese men had odds ratios of 0.879 (CI: 0.0.788-0.98) and 0.874 (CI: 0.782-0.977) compared to 0.918 (95% CI: 0.778-1.083) and 0.916 (95% CI: 0.780-1.075) in overweight and obese women respectively. CONCLUSIONS: Moderate exercise might significantly prevent obese and overweight adults from developing cirrhosis. The benefits appear to be greater for persons who exceed the minimum recommendations of 150 min/wk.

Post-inhaled corticosteroid pulmonary tuberculosis and pneumonia increases lung cancer in patients with COPD.

BACKGROUND: Inhaled corticosteroids (ICS) have been associated with decreased lung cancer risk. However, they have been associated with pulmonary infections (tuberculosis [TB] and pneumonia) in patients with chronic obstructive pulmonary disease (COPD). TB and pneumonia have increased lung cancer risk. The association between post-ICS pulmonary infections and lung cancer remains unclear. METHODS: We conducted a retrospective cohort study from 2003 to 2010 using the Taiwan National Health Insurance Research Database. Among the 1,089,955 patients with COPD, we identified 8813 new users of ICS prescribed for a period of 3 months or more and 35,252 non-ICS users who were randomly matched for sex, age and date of ICS use from 2003 to 2005. Cox proportional hazard regression was used to estimate the hazard ratio (HR) of pulmonary infections in patients with/without ICS use. RESULTS: The HRs for lung cancer in ICS users with sequential lung infections were as follows; 2.42 (95 % confidence interval [CI], 1.28-4.58) for individuals with TB, 2.37 (95 % CI, 1.01-5.54) for TB and pneumonia, and 1.17(95 % CI, 0.69-1.98) for those with pneumonia. For non-ICS users with pulmonary infections, the HRs were 1.68 (95 % CI, 0.78-3.65) for individual with TB and pneumonia, 1.42 (95 % CI, 0.89-2.26) for TB, and 0.95 (95 % CI, 0.62-1.46) for individuals with pneumonia. CONCLUSIONS: COPD patients with TB /or pneumonia who used ICS had increased risk of lung cancer. Because the overall prognosis of lung cancer remains poor, screening tests are recommended for patients with these conditions.

Replacing a piece of loop-structure in the substrate-binding groove of Aspergillus usamii ß-mannanase, AuMan5A, to improve its enzymatic properties by rational design.

To perfect the enzymatic properties of AuMan5A, a mesophilic glycoside hydrolase (GH) family 5 ß-mannanase from Aspergillus usamii, its loop-structure substitution was carried out by rational design and followed by megaprimer PCR. Based on the structural analysis and enzymatic property comparison of various ß-mannanases, a piece of loop-structure with seven amino acids between two ß-strands (ßD and ßE) in the substrate-binding groove, named "Loop DE," was speculated to be correlative to the thermostability and catalytic efficiency of GH family 5 ß-mannanases. Therefore, three AuMan5A's mutants, AuMan5A-Af, AuMan5A-An, and AuMan5A-Th, were designed by substituting a Loop DE sequence ((316)KSPDGGN(322)) of AuMan5A with the corresponding sequences of other three family 5 ß-mannanases, respectively. Then, the mutant-encoding genes, Auman5A-Af, Auman5A-An, and Auman5A-Th, were constructed as designed theoretically and then expressed in Pichia pastoris GS115. The expressed recombinant AuMan5A-Af (re-AuMan5A-Af) displayed the temperature optimum (T opt) of 75 °C, T m value of 76.6 °C and half-life (t 1/2) of 480 min at 70 °C, which were 10 and 12.1 °C higher and 48-fold longer than those of re-AuMan5A, respectively. Its catalytic efficiency (k cat/K m) was 12.7-fold that of re-AuMan5A. What is more, the site-directed mutagenesis of D320G in AuMan5A-Af was performed. The T opt and t 1/2 of expressed re-AuMan5A-Af(D320G) decreased to 70 °C and 40 min, respectively, while its k cat/K m was only 35 % of that of re-AuMan5A-Af. These results demonstrated that the mutation of G320 (in AuMan5A) into D320 (in AuMan5A-Af) through Loop DE substitution was mainly responsible for the thermostability and catalytic efficiency improvement of AuMan5A-Af.

Traveling by Private Motorized Vehicle and Physical Fitness in Taiwanese Adults.

BACKGROUND: Although the time spent sitting in motorized vehicles has been determined to be adversely associated with cardiometabolic health, its association with other health indicators remains unclear. PURPOSE: This study examined associations between traveling by private motorized vehicle and 4 indicators of physical fitness in adults. METHOD: Data from 52,114 Taiwanese adults aged 20 to 65 years who participated in the 2013 National Adults Fitness Survey were used. The examined variables were height, body mass, and performance in modified sit-and-reach (flexibility), bent-leg sit-up (abdominal muscular strength and endurance), and a 3-min step test (cardiorespiratory endurance). Participants were asked on how many days they had used a private car or motorcycle for traveling from place to place and categorized as non-, occasional, and daily private motorized vehicle travelers. Logistic and linear regression models were used to examine associations between the categories of using private motorized vehicles to travel and physical fitness performance. RESULTS: After an adjustment for potential demographic and behavioral confounders, daily traveling by private motorized vehicle was associated with a higher probability of overweight (odds ratio = 1.18), lower performance of abdominal muscular strength and endurance (-0.37 times/min), and lower cardiorespiratory fitness (-0.60 physical fitness index) than was traveling that did not involve private motorized vehicles. CONCLUSION: The results suggest that in addition to unfavorable cardiorespiratory fitness and a risk of overweight, daily traveling by private motorized vehicle is associated with poor performance in abdominal muscular strength and endurance.

Improvement in the thermostability of a type A feruloyl esterase, AuFaeA, from Aspergillus usamii by iterative saturation mutagenesis.

Feruloyl or ferulic acid esterase (Fae, EC 3.1.1.73) catalyzes the hydrolysis of ester bonds between polysaccharides and phenolic acid compounds in xylan side chain. In this study, the thermostability of a type A feruloyl esterase (AuFaeA) from Aspergillus usamii was increased by iterative saturation mutagenesis (ISM). Two amino acids, Ser33 and Asn92, were selected for saturation mutagenesis according to the B-factors analyzed by B-FITTER software and ΔΔG values predicted by PoPMuSiC algorithm. After screening the saturation mutagenesis libraries constructed in Pichia pastoris, 15 promising variants were obtained. The best variant S33E/N92-4 (S33E/N92R) produced a T m value of 44.5 °C, the half-lives (t1/2) of 35 and 198 min at 55 and 50 °C, respectively, corresponding to a 4.7 °C, 2.33- and 3.96-fold improvement compared to the wild type. Additionally, the best S33 variant S33-6 (S33E) was thermostable at 50 °C with a t1/2 of 82 min, which was 32 min longer than that of the wild type. All the screened S33E/N92 variants were more thermostable than the best S33 variant S33-6 (S33E). This work would contribute to the further studies on higher thermostability modification of type A feruloyl esterases, especially those from fungi. The thermostable feruloyl esterase variants were expected to be potential candidates for industrial application in prompting the enzymic degradation of plant biomass materials at elevated temperatures.

Expression of a novel epoxide hydrolase of Aspergillus usamii E001 in Escherichia coli and its performance in resolution of racemic styrene oxide.

The full-length cDNA sequence of Aueh2, a gene encoding an epoxide hydrolase of Aspergillus usamii E001 (abbreviated to AuEH2), was amplified from the total RNA. Synchronously, the complete DNA sequence containing 5', 3' flanking regions, eight exons and seven introns was cloned from the genomic DNA. In addition, a cDNA fragment of Aueh2 encoding a 395-aa AuEH2 was expressed in Escherichia coli. The catalytic activity of recombinant AuEH2 (re-AuEH2) was 1.44 U/ml using racemic styrene oxide (SO) as the substrate. The purified re-AuEH2 displayed the maximum activity at pH 7.0 and 35 °C. It was highly stable at a pH range of 5.0-7.5, and at 40 °C or below. Its activity was not obviously influenced by ß-mercaptoethanol, EDTA and most of metal ions tested, but was inhibited by Hg(2+), Sn(2+), Cu(2+), Fe(3+) and Zn(2+). The K m and V max of re-AuEH2 were 5.90 mM and 20.1 U/mg towards (R)-SO, while 7.66 mM and 3.19 U/mg towards (S)-SO. Its enantiomeric ratio (E) for resolution of racemic SO was 24.2 at 10 °C. The experimental result of re-AuEH2 biasing towards (R)-SO was consistent with the analytical one by molecular docking (MD) simulation.

Synthesis and biological evaluation of novel bis-aromatic amides as novel PTP1B inhibitors.

A series of bis-aromatic amides was designed, synthesized, and evaluated as a new class of inhibitors with IC50 values in the micromolar range against protein tyrosine phosphatase 1B (PTP1B). Among them, compound 15 displayed an IC50 value of 2.34±0.08 µM with 5-fold preference over TCPTP. More importantly, the treatment of CHO/HIR cells with compound 15 resulted in increased phosphorylation of insulin receptor (IR), which suggested extensive cellular activity of compound 15. These results provided novel lead compounds for the design of inhibitors of PTP1B as well as other PTPs.

Examining the relationship between cardiorespiratory fitness and body weight status: empirical evidence from a population-based survey of adults in Taiwan.

BACKGROUND: Cardiovascular disease is the number one cause of death worldwide. Meanwhile, obesity has been recognized as a global epidemic. This study aims to examine the extent to which cardiorespiratory fitness is associated with body mass among adult males and females in Taiwan. MaTERIALS AND METHODS: A nationally representative dataset consisting of 68,175 adults aged 18-60, including 31,743 males and 36,432 females, was used. Several multivariate regression models were used to investigate the relationship between cardiorespiratory fitness and body weight status, after controlling for adults' sociodemographic status. RESULTS: A one-unit increase in the BMI lowered the cardiorespiratory fitness score by 0.316 and 0.368 points for adult males and females, respectively. Among adult males, compared to those of normal weight, adult males who were underweight, overweight, or obese had a lower cardiorespiratory fitness score by 1.287, 0.845, and 3.353 points, respectively. Similar results could be found in female samples. CONCLUSION: The overweight and obese adults had much lower levels of cardiorespiratory fitness as compared to their normal weight counterparts. Given the upward trend in the prevalence of overweight and obesity, it is important to help overweight and obese people to become more fit and reach their healthy weight.

Optimized expression, purification and characterization of a family 11 xylanase (AuXyn11A) from Aspergillus usamii E001 in Pichia pastoris.

BACKGROUND: Xylanases have attracted much attention because of their potential applications. Unfortunately, the commercialization of xylanases is limited by their low catalytic activities. The aim of this study was to improve the activity of a xylanase by optimization of the expression conditions and to investigate its characterization. RESULTS: The activity of recombinant AuXyn11A (reAuXyn11A), a family 11 xylanase from Aspergillus usamii E001 expressed in Pichia pastoris GS115, reached 912.6 U mL⁻¹ under the optimized conditions, which was 2.14 times as high as that expressed using the standard protocol. After the endogenous 18-aa propeptide had been processed in P. pastoris, reAuXyn11A (188-aa mature peptide) was secreted and purified with a specific activity of 22 714 U mg⁻¹. It displayed maximum activity at pH 5 and 50 °C and was stable in the pH range 4-8 and at a temperature of 45 °C or below. Its activity was not significantly affected by most metal ions and EDTA. Xylooligosaccharides ranging from xylobiose (X2) to xylohexaose (X6) were produced from insoluble corncob xylan by reAuXyn11A. CONCLUSION: Its high specific activity and good enzymatic properties suggest that reAuXyn11A is a potential candidate for applications in industrial processes.

Engineering hyperthermostability into a mesophilic family 11 xylanase from Aspergillus oryzae by in silico design of N-terminus substitution.

A mesophilic xylanase from Aspergillus oryzae CICC40186 (abbreviated to AoXyn11A) belongs to glycoside hydrolase family 11. The thermostability of AoXyn11A was significantly improved by substituting its N-terminus with the corresponding region of a hyperthermostable family 11 xylanase, EvXyn11(TS) . The suitable N-terminus of AoXyn11A to be replaced was selected by the comparison of B-factors between AoXyn11A and EvXyn11(TS) , which were generated and calculated after a 15 ns molecular dynamic (MD) simulation process. Then, the predicted hybrid xylanase (designated AEx11A) was modeled, and subjected to a 2 ns MD simulation process for calculating its total energy value. The N-terminus substitution was confirmed by comparing the total energy value of AEx11A with that of AoXyn11A. Based on the in silico design, the AEx11A was constructed and expressed in Pichia pastoris GS115. After 72 h of methanol induction, the recombinant AEx11A (reAEx11A) activity reached 82.2 U/mL. The apparent temperature optimum of reAEx11A was 80°C, much higher than that of reAoXyn11A. Its half-life was 197-fold longer than that of reAoXyn11A at 70°C. Compared with reAoXyn11A, the reAEx11A displayed a slight alteration in K(m) but a decrease in V(max).

Physical fitness and academic performance: empirical evidence from the National Administrative Senior High School Student Data in Taiwan.

This study examined the relationship between the changes of physical fitness across the 3-year spectrum of senior high school study and academic performance measured by standardized tests in Taiwan. A unique dataset of 149 240 university-bound senior high school students from 2009 to 2011 was constructed by merging two nationwide administrative datasets of physical fitness test performance and the university entrance exam scores. Hierarchical linear regression models were used. All regressions included controls for students' baseline physical fitness status, changes of physical fitness performance over time, age and family economic status. Some notable findings were revealed. An increase of 1 SD on students' overall physical fitness from the first to third school year is associated with an increase in the university entrance exam scores by 0.007 and 0.010 SD for male and female students, respectively. An increase of 1 SD on anaerobic power (flexibility) from the first to third school year is positively associated with an increase in the university entrance exam scores by 0.018 (0.010) SD among female students. We suggest that education and school health policymakers should consider and design policies to improve physical fitness as part of their overall strategy of improving academic performance.

Expression of a family 10 xylanase gene from Aspergillus usamii E001 in Pichia pastoris and characterization of the recombinant enzyme.

A cDNA gene (Auxyn10A), which encodes a mesophilic family 10 xylanase from Aspergillus usamii E001 (abbreviated to AuXyn10A), was amplified and inserted into the XhoI and NotI sites of pPIC9K(M) vector constructed from a parent pPIC9K. The recombinant expression vector, designated pPIC9K(M)-Auxyn10A, was transformed into Pichia pastoris GS115. All P. pastoris transformants were spread on a MD plate, and then inoculated on geneticin G418-containing YPD plates for screening multiple copies of integration of the Auxyn10A. One transformant expressing the highest recombinant AuXyn10A (reAuXyn10A) activity of 368.6 U/ml, numbered as P. pastoris GSX10A4-14, was selected by flask expression test. SDS-PAGE assay demonstrated that the reAuXyn10A was extracellularly expressed with an apparent M.W. of 39.8 kDa. The purified reAuXyn10A displayed the maximum activity at pH 5.5 and 50 °C. It was highly stable at a broad pH range of 4.5-8.5, and at a temperature of 45 °C. Its activity was not significantly affected by EDTA and several metal ions except Mn(2+), which caused a strong inhibition. The K(m) and V(max), towards birchwood xylan at pH 5.5 and 50 °C, were 2.25 mg/ml and 6,267 U/mg, respectively. TLC analysis verified that the AuXyn10A is an endo-ß-1,4-D-xylanase, which yielded a major product of xylotriose and a small amount of xylose, xylotetraose, and xylopentose from birchwood xylan, but no xylobiose.

Cloning, expression of a feruloyl esterase from Aspergillus usamii E001 and its applicability in generating ferulic acid from wheat bran.

A cDNA gene (AufaeA), which encodes a mature polypeptide of the type-A feruloyl esterase from Aspergillus usamii E001 (abbreviated to AuFaeA), was cloned and heterologously expressed in Pichia pastoris GS115. One transformant, labeled as P. pastoris GSFaeA4-8, expressing the highest recombinant AuFaeA (reAuFaeA) activity of 10.76 U/ml was selected by the flask expression test. The expressed reAuFaeA was purified to homogeneity with an apparent molecular weight of 36.0 kDa by SDS-PAGE analysis, and characterized using the model substrate of methyl ferulate (MFA). The purified reAuFaeA was optimally active at pH 5.0 and 45 °C, and highly stable at pH 4.0-6.5 and 45 °C or below. Its activity was not significantly affected by metal ions tested and EDTA. The K m and V max of reAuFaeA towards MFA were 4.64 mM and 115.5 U/mg, respectively. High-performance liquid chromatography analysis showed that only 9.7 % of total alkali-extractable ferulic acid (FA) was released from destarched wheat bran by reAuFaeA alone. The released FA increased to 36.5 % when reAuFaeA was used together with a recombinant Aspergillus usamii GH family 11 xylanase A, indicating a synergistic interaction between them.

Urban-rural disparity in physical fitness of elementary schoolchildren in Taiwan.

BACKGROUND: Childhood fitness is generally evaluated by a battery of health-related estimators to assess pediatric health status. More so than the fitness level at any other stage of life, the level of physical fitness in childhood will have a marked effect on an individual's physical development and overall health in adolescence and adulthood. This paper contributes to this issue by investigating the differences in the distribution of the physical fitness of elementary schoolchildren aged 9-12 by gender, region and ethnicity. METHODS: Data were drawn from a nationwide dataset of physical fitness test profiles of elementary school students, conducted by the Ministry of Education in Taiwan in 2008. In total, 134,546 schoolchildren in fourth to sixth grade aged from 9 to 12 were included. Three components of physical fitness are measured: explosive power; muscle strength; and flexibility. Each fitness test was carried out by the school teachers during physical education classes. A statistical test procedure was then used to test the distribution differences in each category of physical fitness by age, gender and region. By further using the official recommended levels, the proportions of schoolchildren who have poor physical fitness performance were also examined. RESULTS: In general, boys have better physical fitness than girls except in the area of flexibility. In addition to gender differences, the present results are supportive of there being differences in the rural and urban populations. The rural children perform better than urban children in bent-leg curl-ups and standing long jump tests. CONCLUSIONS: Physical fitness has been recognized not only as an integrated predictor of the body's functional status, but also as an important marker of health outcomes. Although considerable attention had been paid to examining the urban-rural differences in physical fitness, it is necessary to further consider the differences in ethnicity.

Enhanced thermostability of a mesophilic xylanase by N-terminal replacement designed by molecular dynamics simulation.

BACKGROUND: Xylanases have attracted much attention owing to their potential applications. The applicability of xylanases, however, was bottlenecked by their low stabilities at high temperature or extreme pH. The purpose of this work was to enhance the thermostability of a mesophilic xylanase by N-terminal replacement. RESULTS: The thermostability of AoXyn11, a mesophilic family 11 xylanase from Aspergillus oryzae, was enhanced by replacing its N-terminal segment with the corresponding one of EvXyn11(TS) , a hyperthermotolerant family 11 xylanase. A hybrid xylanase with high thermostability, NhXyn1157, was predicted by molecular dynamics (MD) simulation. An NhXyn1157-encoding gene, Nhxyn1157, was then constructed as designed theoretically, and overexpressed in Pichia pastoris. The temperature optimum of recombinant NhXyn1157 (re-NhXyn1157) was 75 °C, much higher than that of re-AoXyn11. Both xylanases were thermostable at 65 and 40 °C, respectively. Additionally, the pH optimum and stability of re-NhXyn1157 were 5.5 and at a range of 4.0-8.5. Its activity was not significantly affected by metal ions tested and EDTA, but strongly inhibited by Mn²âº and Ag⁺. CONCLUSION: This work obviously enhanced the thermostability of a mesophilic xylanase, making re-NhXyn1157 a promising candidate for industrial processes. It also provided an effective technical strategy for improving thermostabilities of other mesophilic enzymes.

Associations between cigarette smoking status and health-related physical fitness performance in male Taiwanese adults.

Background: The highest proportion of smoking behavior occurs in male adults in Taiwan. However, to our knowledge, no study has investigated the relationship between smoking behavior and health-related physical fitness according to education level, health status, betel nut-chewing status and obesity in male adults aged 18 years or older in Taiwan. Aims: This study aimed to determine the associations between cigarette smoking and health-related physical fitness performance in male Taiwanese adults. Methods: This was a cross-sectional study conducted on 27,908 male adults (aged 23-64 years) who participated in Taiwan's National Physical Fitness Survey 2014-2015. Data from a standardized structured questionnaire, anthropometric variables, and health-related physical fitness measurements were analyzed. Individuals were categorized as never smoking cigarettes, former smoker, and current smoker. Multiple linear regression analysis was performed to evaluate the association between cigarette smoking and health-related physical fitness performance. Results: Never smoking group exhibited a lower (p < 0.05) proportion of abdominal obesity, higher (p < 0.05) proportion of perceived good health status, and greater (p < 0.05) performance in 1-min sit-up and sit-and-reach tests when compared with current smoking and former smoking group. Former smoking group had the highest (p < 0.05) performance in 3-min step test among all groups. Current smoker was significantly negatively (p < 0.05) associated with 3-min step, 1-min sit-up and sit-and-reach tests. Notably, former smoker was significantly positively (p < 0.05) associated with 3-min step and 1-min sit-up tests, but still negatively (p < 0.05) associated with sit-and-reach performance. Conclusion: Current smoker was associated with an increased the risk of abdominal obesity, reduced the perceived health status and health-related physical fitness performance. Quitting smoking had beneficial effect on the perceived good health status, cardiorespiratory and muscular fitness in male Taiwanese adults, but not on flexibility performance. Further research on the ameliorate mechanism underlying this phenomenon is warranted.