Increase in the proportion of fast-twitch muscle fibres by sprint training in males

Fifteen male physical education students were studied. The subjects trained for 4–6 weeks, 2–3 days per week, on a mechanically braked bicycle ergometer. A training session consisted of repeated 30-s ‘all-out’ sprints on a Wingate bicycle ergometer, on which the brake band of the flywheel was loaded with 75 g kg^-1 body wt, with rest periods of 15–20 min between consecutive sprints. Thigh muscle biopsies were taken before and after the training period and were analysed for fibre types using a myofibrillar ATPase stain. The proportion of type I fibres decreased from 57 to 48% (P < 0.05) and type IIA fibres increased from 32 to 38% (P < 0.05). This study indicates that it is possible to achieve a fibre type transformation with high-intensity training. The effect of two-legged ‘sprint’ training on muscle fibre type composition may be related to a changed pattern of muscle fibre activation (e.g. an increased stimulation frequency). A change in fibre activation frequency may induce an increased synthesis of type II fibre myosin (fast myosin). Hormonal influences such as enhanced adrenergic stimulation of the muscle fibres cannot be excluded as a contributing factor, however.     

环境物理因子的最佳条件的选择

目的：利用黄金数比例规律找出环境物理因子对人体的最佳条件：方法：人体的相当一部分内容与黄金数有着密切的联系，为此把复杂的人体可以简化为比例加破缺的比例实体；环境物理因子：如环境温度、湿度、环境光波和声波以及环境气压和氧分压，当它们处在黄金数比例附近时，会在人体产生和谐合柏作用。结果：环境物理因子选择在黄金数比例附近时，在心理上产生美和舒适感。已经发现，当精神愉快时，人脑电波频率下限(8Hz)和上限(12．9Hz)之比恰为黄金数。结论：环境物理因子的最佳条件是可以选择的。     

Infrared spectroscopy: A new diagnostic tool in Alzheimer disease

Biological markers play an evolving role in the diagnosis of Alzheimer disease (AD). We compare conventional measurements of cerebrospinal fluid (CSF) tau and β-amyloid_1–42 proteins to a novel approach – Fourier transformed infrared (FT-IR) spectroscopy – a simple technique derived from chemical and physical sciences that characterizes intramolecular bonds. For automatic diagnostic analysis, we developed an artificial neural network (ANN). We examined 71 patients with a clinical diagnosis of AD and 66 controls. β-Amyloid_1–42 was decreased (sensitivity 80% and specificity 78%); tau was elevated (sensitivity 76% and specificity 88%) in CSF of AD patients. The combined tau/β-amyloid_1–42 quotient was able to distinguish healthy from diseased subjects with 99% sensitivity and 86% specificity. The ANN could separate FT-IR spectroscopy data with 88.5% sensitivity and 80% specificity. FT-IR spectroscopy proved to be cost-effective and simple to perform. Diagnostic sensitivity and specificity is in the range of CSF tau and β-amyloid_1–42 protein analysis. Larger sample numbers for ANN training and validation could increase diagnostic accuracy and thus prove to be a useful screening tool.     

Energy Balance,Eating Disorder Risk,and Pathogenic Behaviors Among Athletic Trainers

ContextResearch exists on energy balances (EBs) and eating disorder (ED) risks in physically active populations and occupations by settings, but the EB and ED risk in athletic trainers (ATs) have not been investigated.ObjectiveTo assess ATs'' energy needs, including the macronutrient profile, and examine ED risk and pathogenic behavioral differences between sexes (men, women) and job statuses (part time or full time) and among settings (college or university, high school, nontraditional).DesignCross-sectional study.SettingFree living in job settings.Patients or Other ParticipantsAthletic trainers (n = 46; male part-time graduate assistant ATs = 12, male full-time ATs = 11, female part-time graduate assistant ATs = 11, female full-time ATs = 12) in the southeastern United States.Main Outcome Measure(s)Anthropometric measures (sex, age, height, weight, body composition), demographic characteristics (job status [full- or part-time AT], job setting [college/university, high school, nontraditional], years of AT experience, exercise background, alcohol use), resting metabolic rate, energy intake (EI), total daily energy expenditure (TDEE), EB, exercise energy expenditure, macronutrients (carbohydrates, protein, fats), the Eating Disorder Inventory-3, and the Eating Disorder Inventory-3 Symptom Checklist.ResultsThe majority of participants (84.8%, n = 39) had an ED risk, with 26.1% (n = 12) engaging in at least 1 pathogenic behavior, 50% (n = 23) in 2 pathogenic behaviors, and 10.8% (n = 5) in >2 pathogenic behaviors. Also, 82.6% of ATs (n = 38) presented in negative EB (EI < TDEE). Differences were found in resting metabolic rate for sex and job status (F_1,45 = 16.48, P = .001), EI (F_1,45 = 12.01, P = .001), TDEE (F_1,45 = 40.36, P < .001), and exercise energy expenditure (F_1,38 = 5.353, P = .026). No differences were present in EB for sex and job status (F_1,45 = 1.751, P = .193); χ² analysis revealed no significant relationship between ATs'' sex and EB (= 0.0, P = 1.00) and job status and EB ( = 2.42, P = .120). No significant relationship existed between Daily Reference Intakes recommendations for all macronutrients and sex or job status.ConclusionsThese athletic trainers experienced negative EB, similar to other professionals in high-demand occupations. Regardless of sex or job status, ATs had a high ED risk and participated in unhealthy pathogenic behaviors. The physical and mental concerns associated with these findings indicate a need for interventions targeted at ATs'' health behaviors.     

Adaptive changes in cerebral blood flow and oxygen consumption during ethanol intoxication in the rat

Cerebral blood flow (CBF) and oxygen consumption (CMRO₂) were measured during acute and long-term ethanol intoxication in the rat. The purpose was to investigate whether the adaptive changes (development of tolerance) occurring in the CNS during ethanol intoxication were associated with changes in CBF and/or CMRO₂. Consistent with other studies we found that acute severe ethanol intoxication (median blood alcohol concentration (BAC=5.4 mg/ml)) caused a significant decrease in CBF and CMRO₂. After 3–4 days of severe intoxication (BAC of 6.6 mg/ml) these physiological variables were less affected indicating that functional tolerance had developed: CMRO₂ and CBF during acute ethanol intoxication were 9.3 ml/100 g/min and 60 ml/100 g/min respectively; after the long term intoxication period these variables reached 11.2 ml/100 g/min and 78 ml/100 g/min respectively, i.e. values not significantly lower than those of the control group. After induction of hypercapnia (PaCO₂ about 80 mmHg) CBF increased by 360% in the control group; in the acutely intoxicated group CBF increased by only 127% and in the long term intoxicated group by 203 % indicating that the cerebrovascular CO₂-reactivity had also adapted to the ethanol intoxication. It is concluded that adaptive changes of the CNS to chronic ethanol intoxication comprise alterations in CMRO₂, CBF and cerebrovascular reactivity.     

Review of 1,000 consecutive cases of severe head injury treated before the advent of CT scanning

Summary This is a review of 1,000 consecutive cases of severe head injury admitted to our Neurosurgical Department between January 1973 and August 1976, before the advent of CT scanning. All patients were comatose following head injury (GCS8) and were treated homogeneously by the same neurosurgical team by a protocol that included immediate resuscitation on arrival, diagnosis of intracranial lesions by angiography, early surgery when needed, mechanical ventilation, steroids, and mannitol. Extracranial lesions, even if preponderant, were treated by various specialists in the Neurosurgical Department, which for all practical purposes operated as an Emergency Department. Admission criteria were very broad with no preadmission selection. The overall mortality for this series was 45%. A little less than half the patients made good recoveries or remained moderately disabled (47%); 6% were severely disabled, and 2% survived in a persistent vegetative state. More than two-thirds of the patients were brought to our Neurosurgical Department after a short stay at a general hospital; 72% were admitted within 6 hours of injury; 71% were traffic accident victims; and 34% had significant associated extracranial injuries. Carotid angiography was performed in 78% of the patients and indicated the presence of an intracranial haematoma requiring surgery in 36% of the whole series. Mortality was significantly higher in operated than in unoperated patients (56% versus 39%); those treated surgically, however, were older, in worse clinical condition, and showed a higher incidence of acute subdural haematomas associated with brain contusion. Carotid angiography proved very effective in revealing the presence of an expansive lesion but failed to reflect the severity of brain damage, since the group with negative angiograms showed a high mortality (52%). Patients with a lucid interval had a higher percentage of surgical lesions than those with immediate coma (58% versus 26%); but fully 42% of them did not require surgery, and 25% had negative angiograms. From the prognostic point of view the clinical data elicited after initial resuscitation were highly predictive of the outcome: some individual neurological signs, such as mydriasis, posturing and eye movements, were not inferior to the GCS score in that respect. Age also proved a strong predictor, since elderly patients are more likely to have severe subdural and parenchymal lesions and their clinical severity is accordingly greater.Our series amounts to a data bank of cases both contemporary to and in good agreement with that collected by Jennett and his associates in their 1977 multinational study; and it affords a useful reference in the assessment of epidemiological variations and alternative management in relation to outcome.     

Optimum support properties for protein separations by high-performance size exclusion chromatography

Optimum chromatographic properties of high performance size exclusion chromatography (HPSEC) of proteins, such as resolution, molecular weight accuracy and recovery, are obtained on packings and columns with tailor-made physical and chemical structures, employed at properly adjusted eluent compositions and operation conditions. SEC-theory suggests that a broad molecular weight fractionation range and high linearity of the log-linear calibration plot can be achieved by the use of two packings (10- and 80-nm pore size, characterized by a pore-size distribution (psd) equal to or less than 1 decade and by equal internal column porosity (p)), rather than a single 30- to 50-nm pore-size packing with a wide psd. Favourably high-phase ratios of (p)/(o)/ 1.0 for HPSEC columns were accomplished with a minimum interstitial column porosity (o) and a high value for the internal column porosity (p) (the specific pore volume, nu(p), multiplied by the packing density, varrho(p).) Ligands such as diol, N-acetoxyamino and oligomeric ether with a propyl- or propoxy-spacer bonded to the silica at the highest density appear to provide high mass recovery and bioactivity as well as chemical stability. Such packings, available in 3-5 mum particle size ranges of narrow distribution, packed into columns 6 mm i.d. and 500 mm in length, offer the best compromise with respect to resolution, speed and pressure drop. More careful studies are required to explain the effects of protein conformational changes and interconversions during elution on HPSEC columns.     

儿童体质发展情况分析

目的 对昆明市城区连续三年3~6岁学龄前儿童体质测试结果进行分析,寻找学龄前儿童体质发展中的不平衡点,为制定体格锻炼、全面提高学龄前儿童身体素质的相关措施提供建议。 方法 选取2017-2019年连续进行体质测定的昆明市城区幼儿园38所,采用SPSS 20.0统计软件对结果进行数据分析。相关指标包括:身高、体重、10米折返跑、立定跳远、网球掷远、双脚连续跳、坐位体前屈、走平衡木8个体质项目,以及年龄别身高、年龄别体重、身高别体重3个生长发育评价结果。 结果 2019年体质测定的优秀率从2018年的32.5%提高到35.7%(χ²=62.512,P<0.05)。坐位体前屈0分值比率从2018年的1.7%上升到2019年的3%;除10米折返跑外,其余五个项目5分值比率2019年较2018年上升了1.8%~8.8%。与正常儿童6个项目相比,身高低常儿童平均分低1.855分(t=-16.416,P<0.05),体重低常儿童平均分低1.856分(t=-17.346,P<0.05);体重超常儿童平均分低0.277分(t=-2.798,P<0.05),消瘦儿童平均分低0.917分(t=-6.073,P<0.05),肥胖儿童平均分低0.571分(t=-5.490,P<0.05);身高超常儿童平均分高0.812分(t=7.123,P<0.05),且这生长发育异常的儿童在6个体质项目表现中,大部分项目的低分(0~2分)比率高于正常儿童。 结论 重视儿童柔韧性、平衡性锻炼,加强对家长的健康教育及认识的提高,做好儿童健康管理,做到早期预防及治疗生长发育相关疾病,才能持续促进体质健康发展,保障儿童健康。     

2017—2019年北京某高校教职工健康体检结果分析

目的 掌握中国人民大学教职工的健康状况及变化趋势,为改善教职工的生命质量、提出合理的健康教育和促进策略提供数据支持。方法 将2017—2019年参加体检的中国人民大学的教职工(含离退休人员)纳入研究,对获得的体检资料进行分析,采用χ2趋势检验分析异常指标在2017—2019的变化趋势。结果 2017—2019年有效体检的教职工人数分别为6 082,6 088和6 507人,各年的平均年龄在44～45岁左右,其中女性多于男性。全体职工在2017—2019年3年间高血压检出率分别为16.29%、15.85%、20.01%;高血糖检出率分别为12.20%、17.34%、29.29%;尿酸偏高检出率分别为16.36%、20.28%、20.81%;心电图异常的检出率分别为14.24%、17.58%、19.43%,检出率均逐年递增;而血脂异常检出率分别为44.33%、32.29%、32.1%;血清谷丙转氨酶偏高的检出率分别为9.48%、7.62%、7.82%,检出率呈现降低趋势(P<0.05)。2017—2019年,在各个年龄组中高血糖检出率最低为2017年<35岁组(0.81%),最高为2019年≥60岁组(48.55%);尿酸偏高的检出率最低为2017年<35岁组(15.04%),最高为2018年≥60岁组(24.4%),均明显上升,血脂异常和谷丙转氨酶偏高的检出率在各个年龄组呈下降趋势(P<0.05),血脂异常检出率最低为2019年<35岁组(15.96%),最高为2017年50～59岁组(50.79%);谷丙转氨酶偏高检出率最低为2018年≥60岁组(7.62%),最高为2019年35～49组(12.08%)。校正了年份、年龄和性别后,高血压、高血糖、血脂异常、尿酸偏高、谷丙转氨酶偏高和心电图异常的检出率均随着BMI的升高而递增(P<0.05),各项指标在肥胖组的检出率分别为30.83%、33.7%、58.51%、45.67%、27.97%和21.0%。结论 2017—2019年本校教职工的健康状况不容乐观,高血压、高血糖、尿酸偏高和心电图异常的检出率均呈现上升的趋势,血脂异常的检出率呈现逐年下降,35岁以下教职工心电图异常检出率升高明显。     

US Food and Drug Administration Analysis of Patient-Reported Diarrhea and Its Impact on Function and Quality of Life in Patients Receiving Treatment for Breast Cancer

ObjectivesMany trials conclude “no clinically meaningful detriment” to health-related quality of life (HRQL) or function between arms, even when notable differential toxicity is observed. Mean change from baseline analyses of function or HRQL can possibly obscure important change in subgroups experiencing symptomatic toxicity. We evaluate the impact of diarrhea, a key treatment arm toxicity, on patient-reported HRQL and functioning in clinical trials submitted to US Food and Drug Administration.MethodsThis study used 4 randomized, breast cancer trials (adjuvant to late-line metastatic) as case examples. Diarrhea, physical functioning (PF), and global health status and quality of life (GHS/QoL) from the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-C30 were analyzed at baseline and approximately 3 and 6 months.ResultsGenerally, patients reporting very much diarrhea at months 3 and 6 had worse PF (9-19 points lower) and GHS/QoL (16-19 points lower) than patients reporting no diarrhea regardless of treatment arm. In the change from baseline analysis, patients reporting very much diarrhea also experienced a greater decrease in PF (6-13 points) and GHS/QoL (6-16 points) versus patients reporting no diarrhea in both arms.ConclusionsIn trials with moderate to large differences in symptomatic toxicity by arm, reporting “no meaningful difference in functioning and HRQL between arms” based on mean change from baseline analysis is insufficient and may obscure important impacts on subgroups experiencing symptomatic adverse events. Additional exploratory analyses with simple data visualizations evaluating functioning or HRQL in patient subgroups experiencing expected symptomatic toxicities can further inform the safety and tolerability of an investigational agent.