Measurement and evaluation of the quadriceps muscle mass in young men based on magnetic resonance imaging / 北京大学学报(医学版)

OBJECTIVE@#To investigate the correlation between the quadriceps cross-sectional area (CSA) and quadriceps muscle volume (QMV) at different horizontal levels from the upper edge of the patella, and to determine the best observation position.@*METHODS@#Thigh magnetic resonance imaging (MRI) images of 22 Chinese young men [age: (29±6) years] with anterior cruciate ligament (ACL) rupture were examined. The CSA was measured at 18, 15, and 12 cm above the upper edge of the pate-lla (denoted by CSA-18, CSA-15 and CSA-12 respectively), and the QMV and CSA were determined by semiautomatic segmentation. A curve model was established to estimate QMV. Bland-Altman analysis was performed to determine the confidence limits of the volumes.@*RESULTS@#On the unaffected side, the mean QMV was (1 944.45±323.77) cm3. The quadriceps CSA at the upper edge of the patella at 18, 15, and 12 cm was (80.80±12.16) cm2, (77.53±12.03) cm2, and (72.68±10.51) cm2, respectively. The coefficients of determination (R2), ascertained using curve estimation models, for the 3 positions were 0.819, 0.755, and 0.684 (P < 0.001), and the standard deviations of the volume estimated value (SEE) were 7.4%, 8.7%, and 9.8%. The fitting equations of the three horizontal positions were all good, but the fitting degree of CSA-18 was the highest. The Bland-Altman scatter plot showed that the arithmetic means of the QMV at 18, 15 and 12 cm from the upper edge of the patella 0.8 cm3, -1.1 cm3, and 0.9 cm3 and 95% limits of agreement (LoA) were (-268.8, 270.5), (-315.2, 313.1), and (-355.7, 357.5), respectively. The estimated QMV was in good agreement with the measured value. The difference between the estimated CSA-18 and measured values was the smallest. The results on the affected side were consistent.@*CONCLUSION@#The correlation between QMV and CSA in the young men with the upper edge of patella as baseline was reliable and consistent. Among them, CSA-18 had the highest correlation with the QMV. However, different observation sites could be selected for different injuries of the quadriceps.

Research Progress on Application of Sports Beverage to Post-exercise Fluid Restoration / 中国医学科学院学报

A good hydration status is important to the exercise performance and cognitive function of exercisers.The effective restoration of fluid balance after exercise is helpful to prevent dehydration,maintain body fluid balance,accelerate fatigue recovery,and enhance exercise performance.As the most effective sports nutrition supplement,sports beverage has different ingredients and formulas,and also has various effects.To provide clues for the development of sports beverage,this article reviews the types,components,effects,and mechanisms of sports beverage currently used in post-exercise fluid restoration.

Effect of the Seasonal Adaptability on Carbohydrate-electrolyte Beverage Efforts on Post-exercise Rehydration in Healthy Young Men / 中国医学科学院学报

Objective To compare the effects of carbohydrate-electrolyte beverage on post-exercise rehydration of healthy young men in different seasons,and to explore the influence of seasonal adaptability on fluid and electrolyte balance.Methods Fifteen healthy men,aged(24.4±0.5)years,completed 2 trails in a random crossover design both in summer and winter.During recovery,they consumed a drink volume equivalent to 100% of their sweat loss with plain boiled water(the water group)or carbohydrate-electrolyte beverage(the beverage group).Recovery was monitored for further 180 minutes by the collection of blood and urine samples.Results The dehydration time in summer was significantly shorter by about 20 minutes than that in winter(

Establishment of high-fat diet-induced obesity and insulin resistance model in rats / 北京大学学报(医学版)

OBJECTIVE@#To investigate the appropriate conditions and duration for establishing a high-fat diet-induced obesity and insulin resistance model in rats.@*METHODS@#Forty-five 6-week-old male Sprague-Dawley (SD) rats were randomly assigned into 2 groups: (1) control group (CON), (2) high-fat diet group (HFD). HFD was fed with a high-fat diet (45% kcal from fat) while CON with chow diet. After four-weeks of high-fat diet feeding, the rats of obesity resistance (OR) were eliminated according to body weight sorting, whereas obese (OB) rats were continued feeding a high-fat diet until 12 weeks. Body weight and food intake were recorded weekly. Glucose tolerance was evaluated by oral glucose tolerance test (OGTT) in 4 weeks, 8 weeks and 12 weeks. At the end of 12 weeks, insulin releasing test and visceral fat mass were measured and HE staining of the liver, adipose tissue and pancreatic tissue were conducted.@*RESULTS@#After 4 weeks of a high-fat diet, the body weight of HFD was 17.8% higher than that of CON (P=0.001), and the rate of obesity was 67.6%-78.4%. Glucose tolerance of OB rats was impaired with a higher blood glucose concentration at 120 min (P<0.001) and a higher area under the curve (AUC, P=0.037) in OGTT compared with CON. The rate of obesity and insulin-resistance rats was 79.3%. After 8 weeks of feeding, the body weight in OB was 30.4% higher than CON (P<0.001). In OGTT, blood glucose levels at 60 min and 120 min were 35.6% and 36.4% higher than those in CON (both P<0.001), and AUC was 21.7% (P<0.001) higher than that of CON. The rate of obesity and insulin-resistance rats was 100.0%. After 12 weeks of feeding, the body weight in OB was 36.9% higher than that in CON (P<0.001). In OGTT, the blood glucose levels at 60 min and 120 min were 24.8% (P=0.001) and 34.6% (P<0.001) higher than those in CON, and AUC was 16.1% (P=0.019) higher than that of CON. The rate of obesity and insulin-resistance rats was 93.3%. The insulin releasing test showed that serum insulin concentration at each time point (0, 30, 60, 120 min) was higher than that in CON, with a 6.3-times higher than that in CON at 120 min (P=0.008). Pathological changes were observed in islets and liver in the OB rats.@*CONCLUSION@#After 4 weeks of a high-fat diet (45% kcal from fat) feeding in six-weeks SD rats, the rats of OR were eliminated. Impaired glucose tolerance was found in OB rats after 4 weeks of feeding, and the rate was higher after 8-12 weeks of high-fat diet feeding.

Effects of chlorogenic acid on glucose tolerance and its curve characteristics in high-fat diet-induced obesity rats / 北京大学学报(医学版)

OBJECTIVE@#To observe the effect of chlorogenic acid (chlorogenic acid, CGA) on the glucose tolerance and its curve characteristics in high fat diet-induced obesity (diet-induced-obesity, DIO) rats, so as to provide scientific grounds for the development and utilization of CGA in early prevention and reversal of prediabetes.@*METHODS@#Eight of forty-six male Sprague-Dawley rats were randomly selected as the normal diet group (CON group), and the rest were fed with high-fat diet. After 4 weeks, 24 high-fat-induced obese rats were screened according to the criteria and then randomly divided into high fat diet group (HFD group), 50% CGA group and 98% CGA group. The CGA groups received intragastric administrations of 50% CGA and 98% CGA orally via a gavage needle once a day for 8 weeks, respectively, while the CON and HFD groups received a carrier solution (phosphate buffer saline, PBS). Their body weights were measured weekly and oral glucose tolerance test (OGTT) was performed every 4 weeks. Fasting insulin and insulin release were measured at the end of the study. Meanwhile, HOMA-IR and visceral fat percentage were calculated. Histopathological examination by hematoxylin and eosin staining method were evaluated in the pancreatic tissues.@*RESULTS@#Before the intervention of chlorogenic acid, blood glucose levels 120 min after glucose loading (P<0.05) and AUC-G (P<0.05) were increased in the HFD group when compared with the CON group, and the time to glucose peak was delayed after 4 weeks of chlorogenic acid intervention (P<0.05). After 8 weeks of intervention, the HOMA-IR index, the insulin levels at 0 min, 30 min, 60 min, and 120 min after glucose loading and AUC-I increased (P<0.05), and the histopathological examination showed obvious hyperplasia of pancreatic islets (P<0.05). Compared with the HFD group, there was no significant change in glucose tolerance and glucose peak time in 50%CGA and 98%CGA groups at the end of 4 weeks of intervention. However, after 8 weeks of intervention, OGTT-60min,OGTT-120min blood glucose (P<0.05) were lower, HOMA-IR index and OGTT-0min, OGTT-120min serum insulin level decreased (P<0.05), the time to glucose peak shifted to an earlier timepoint (P<0.05), abnormal islet hyperplasia attenuated (P<0.05) in 50% CGA and 98% CGA groups. Also, the OGTT-30min serum insulin level was decreased (P<0.05) in 50% CGA group.@*CONCLUSION@#Delay in time to glucose peak during the OGTT was one of the manifestations of impaired glucose tolerance in DIO rats, and 50% and 98% CGA could improve the glucose tolerance and delay in glucose peak time.

Acupuncture ameliorates negative emotion in PCOS patients: a randomized controlled trial / 中国针灸

OBJECTIVE@#To evaluate the effectiveness and possible mechanism of acupuncture treatment for negative emotion in patients with polycystic ovary syndrome (PCOS).@*METHODS@#A total of 40 PCOS patients were randomly divided into an observation group and a control group, 20 cases in each one. Both groups received lifestyle interventions (exercise and diet guidance) on the 5th day of menstruation. On the basis of above treatment, the patients in the observation group received acupuncture at Guanyuan (CV 4), Zhongwan (CV 12), Guilai (ST 29), Futu (ST 32), Liangqiu (ST 34), Sanyinjiao (SP 6), Zusanli (ST 36), Hegu (LI 4), Shenmen (HT 7), Baihui (GV 20) as the main acupoints, and connected the electroacupuncture (continuous wave, 2 Hz, 30 min), once every other day, 3 times a week. The treatment for 1 month was as one course and 4 courses were required totally in both groups. Before and after treatment, the body mass index (BMI), ferriman-gallway (F-G) score, self-rating anxiety scale (SAS) score, self-rating depression scale (SDS) score, PCOS health-related quality of life questionnaire (PCOSQ) score were observed, meanwhile, serum sex hormone, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), estrogen (E), progestin (P), prolactin (PRL), testosterone (T), sex hormone-binding globulin (SHBG) and free androgen index (FAI) levels, and serumβ-endorphin levels were detected.@*RESULTS@#Compared with before treatment, the BMI, F-G score, SAS score, SDS score and serum FAI level were decreased and the PCOSQ score and the levels of serum SHBG andβ-endorphin were increased in the observation group after treatment (all <0.05). Compared with before treatment, the SDS score was decreased in the control group after treatment (<0.05). Compared with the control group, the F-G score, SDS score, SAS score, and serum FAI level were lower, and the PCOSQ score and serumβ-endorphin level were higher in the observation group after treatment (all <0.05).@*CONCLUSION@#Applying acupuncture to the treatment of patients with PCOS can effectively relieve anxiety and depression, and the mechanism may be related to the regulation on the levels of serumβ-endorphin and androgen.

Application of Internet-based Interventions in Weight Management / 中国医学科学院学报

Overweight and obesity are associated with a range of chronic diseases and have become a major global health concern. With the progress of Internet technology,electronic health care has emerged,providing new tools and Methods for weight management. Internet-based technology has shown certain effectiveness in facilitating interventions on overweight,obesity,and their associated diseases. This article reviews the recent advances in these interventions and evaluates their effectiveness,efficiency,and feasibility.

Effects of Preoperative Isokinetic Eccentric Training and Whey Protein Isolate Supplement on Quadriceps Strength and Knee Function in Patients with Anterior Cruciate Ligament Rupture / 中国医学科学院学报

Objective To explore the effect of preoperative isokinetic eccentric training with or not whey protein isolate supplement before operation on lower limb muscle strength and knee function in patients with anterior cruciate ligament (ACL) rupture. Methods A total of 22 male volunteers aged 18-40 years with ACL rupture were recruited in outpatient service. With randomized block design,subjects were randomly assigned to isokinetic eccentric training (IE) group and isokinetic eccentric training with whey protein isolate supplement (IE+WPI) group. The IE group received isokinetic eccentric training of the injured limb on an isokinetic dynamometer under the guidance of physiatrist in laboratory before operation. There were 3-4 sets per day with 8-10 repetitions for each set,twice a week,with at least one day between sessions. The IE+WPI group were supplied with whey protein isolate 22 g per day on the basis of isokinetic eccentric training,taking breakfast or 30-60 minutes after the training. The intervention lasted for 6 weeks. Isokinetic muscle strength of limbs,the function and laxity of knee,the circumferences of thigh and knee,and the body composition were measured before and after the treatment. Results Compared with baseline,the peak torque (PT) of isokinetic-eccentric contraction (IE group:41.0%,P=0.018;IE+WPI group:46.7%,P=0.008) and the concentric contraction (IE group:29.6%,P=0.018;IE+WPI group:38.9%,P=0.038) of quadriceps in the two training groups significantly increased after isokinetic eccentric training. The Lysholm score increased significantly in IE+WPI group compared with baseline (P=0.018). Conclusions Isokinetic eccentric training before operation for ACL rupture patients can increase the strength of quadriceps and improve the function of knees. Protein isolate supplement can improve such effect.

Effect of Interaction between PLIN Gene Polymorphisms and Open Lifestyle Intervention on Weight-loss in Chinese Han Adults / 中国医学科学院学报

<p><b>OBJECTIVE</b>To explore the effect of the interaction between PLIN gene polymorphisms and open lifestyle intervention on weight-loss in Chinese Han adults.</p><p><b>METHODS</b>Totally 109 overweight or obese subjects were assigned by random number table to the intervention group (n=56) or control group (n=53),and subjects in the intervention group received 22-week open lifestyle intervention. Anthropometric and metabolic indicators were measured for all subjects before and after intervention,and the PLIN1,PLIN4,and PLIN6 genotypes were amplified by polymerase chain reaction and sequenced through the first-generation sequencing technologies.</p><p><b>RESULTS</b>Among all these subjects,the rare allele C was dominant at PLIN1 (0.619),the common allele G was dominant at PLIN4 (0.606),and the common allele A was dominant at PLIN6 (0.564),in which PLIN1 and PLIN4 as well as PLIN4 and PLIN6 were in strong linkage disequilibrium (D'>0.9). After intervention,the body mass index,waist circumference,and body fat percent of female subjects were significantly decreased in intervention group and were lower than in control group;in male subjects,however,only the waist circumference showed significant difference with the control group (P<0.05). Subjects carrying rare allele homozygote of PLIN6 got less weight/fat loss than those carrying common alleles in intervention group,while subjects carrying rare allele of PLIN1 had more weight/fat increase than those with common allele homozygote in control group (P<0.05). Females in intervention group carrying any one of rare allele homozygotes of PLIN1,PLIN4 and PLIN6 got less weight/fat loss than those with common alleles,and female subjects carrying the rare allele homozygote haplotype of PLIN1/PLIN4 or PLIN4/PLIN6 got less weight/fat loss than those with other haplotypes (P<0.05).</p><p><b>CONCLUSION</b>The interaction between open lifestyle intervention and PLIN gene polymorphisms can directly influence weight-loss in Chinese Han overweight and obese adults.</p>

Up-regulation of visfatin expression in subjects with hyperthyroidism and hypothyroidism is partially relevant to a nonlinear regulation mechanism between visfatin and tri-iodothyronine with various concentrations / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Visfatin, a visceral fat-derived adipocytokine, plays a significant physiological function in lipid metabolism. However, the precise function of visfatin and its regulation by thyroid hormones are still unknown. This study observed the plasma visfatin concentrations in subjects with hyperthyroidism and hypothyroidism in vivo, and investigated the possible regulation mechanism between visfatin and tri-iodothyronine (T3) in vitro as a further interpretation.</p><p><b>METHODS</b>The experiment in vivo included clinical subjects (57 patients with thyroid dysfunction and 29 euthyroid healthy volunteers) and an animal model (24 Wistar rats). All subjects were divided into hyperthyroidism, hypothyroidism and euthyroidism groups, with plasma thyroid hormones, thyrotropin, visfatin and triglyceride concentrations determined. Visfatin mRNA expression in visceral fat and liver of rats was detected by quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR). The experiment in vitro studied 3T3-L1 cells and visfatin mRNA expression under nine different T3 concentrations (0, 0.1, 0.25, 0.5, 1, 5, 10, 20, 100 nmol/L) using quantitative real-time RT-PCR.</p><p><b>RESULTS</b>Clinical subjects and animal models showed elevated plasma visfatin concentrations in the hyperthyroidism group (20.466 ng/ml (15.263, 26.795 ng/ml) and (1209.164±165.292) ng/L) and hypothyroidism group (12.457 ng/ml (11.115, 15.454 ng/ml) and (1205.425±109.200) ng/L) compared to euthyroidism group (6.891 ng/ml (5.888, 8.803 ng/ml) and (926.650±54.002) ng/L, P<0.001). For animal models, visfatin mRNA expression in visceral fat in the hyperthyroidism and hypothyroidism groups increased about 3.33-fold and 1.98-fold compared to the euthyroidism group (P<0.001), which was positively correlated with plasma visfatin concentrations (r=0.713, P<0.001). However, no significant group difference (P>0.05) and correlation (r=0.121, P=0.572) was found in the liver. T3 induced a remarkable increase of visfatin mRNA expression in 3T3-L1 cells at low concentrations (0-0.5 nmol/L T3) followed by a sharp decrease at higher concentrations (0.5-100 nmol/L T3), with an inflection point at 0.5 nmol/L T3.</p><p><b>CONCLUSION</b>Elevated circulating visfatin levels in subjects with hyperthyroidism and hypothyroidism are possibly due to an increase of visfatin mRNA expression in visceral fat, and a nonlinear regulation mechanism on visfatin mRNA expression under various T3 concentrations might be involved.</p>

Individualized exercise training prescription for patients with type 2 diabetes mellitus / 中国医学科学院学报

Exercise training plays a critical role in the prevention and control of type 2 diabetes mellitus (T2DM). New guidelines on exercise training for T2DM patients was jointly published by American College of Sports Medicine and American Diabetes Association at the end of 2010. In the Guidelines on Prevention and Treatment of Type 2 Diabetes Mellitus in China issued by Chinese Diabetes Society, the role of exercise training is also clearly defined. The implementation of guidelines requires individualized exercise training prescription and program. In this article, we review the procedure of individualized aerobic exercise training prescription, resistant exercise, safety issues, and other relevant topics.

Effect of chlorogenic acid on disordered glucose and lipid metabolism in db/db mice and its mechanism / 中国医学科学院学报

<p><b>OBJECTIVE</b>To explore the effect of chlorogenic acid on disordered glucose and lipid metabolism in db/db mice and its mechanism.</p><p><b>METHODS</b>Thirteen 5-6-week-old male db/db mice were randomly divided into db/db-CGA group (n=7) and db/db-CON group (n=6), and thirteen 5-6-week-old male db/m mice were randomly divided into db/m-CGA group (n=6) and db/m-CON group (n=7). Mice in the CGA groups were administrated with CGA 80 mg/(kg·d)by gavage, and mice in the CON groups were administrated with PBS in the same volume by gavage. Twelve weeks later, the level of biomedical parameters in plasma, liver, and skeletal muscle were determined, the concentrations of adiponectin and visfatin in visceral adipose, and the mRNA expression of glucose-6-phosphatase (G-6-Pase) and peroxisome proliferators-activated receptor-α (PPAR-α) as well as the protein level of PPAR-α in liver were detected.</p><p><b>RESULTS</b>Twelve weeks after CGA administration, the levels of triglycerides in plasma, liver, and skeletal muscle and the fasting plasma glucose in db/db-CGA group were significantly lower than those in db/db-CON group(P<0.05). The muscle glycogen level was significantly higher than that in db/db-CON group (P<0.05), and the adiponectin concentration was significantly higher than that in db/db-CON group ( P<0.01) and lower than that in db/m-CGA group(P<0.05). The visfatin concentration in db/db-CGA group was significantly lower than that in db/db-CON group (P<0.01) and significantly higher than that in db/m-CGA group(P<0.05). The mRNA expression level of G-6-Pase was significantly down-regulated in db/db-CGA group when compared with db/db-CON group (P<0.05). Both the mRNA and the protein expression levels of PPAR-α were significantly up-regulated in db/db-CGA group(P<0.05) compared with in db/db-CON group.</p><p><b>CONCLUSION</b>CGA improves the disordered glucose/lipid metabolism in db/db mice, which is speculated to be related with its role in modulating the adipokines secretion, up-regulating hepatic PPAR-α, and inhibiting G-6-Pase expression.</p>

Effects of a carbohydrate-electrolyte beverage on blood viscosity after dehydration in healthy adults / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The consumption of carbohydrate-electrolyte beverages (CEs) has been known to be more effective than plain water for recovery from dehydration. This phenomenon suggests that the ingestion of CEs after dehydration is better than water for maintaining body fluid and plasma volume, and for the recovery from hemoconcentration and high blood viscosity as well. High blood viscosity causes infarction and other cardiovascular events. In this study, CE was compared with water and tea for the ability to reduce increased blood viscosity after dehydration.</p><p><b>METHODS</b>A crossover random control study was conducted to assess the effectiveness of three beverages for rehydration and decreasing of blood viscosity. Following exercise-induced dehydration of 2.2% of body weight in a permanent warm environment, 10 male subjects rested in a thermoneutral environment for 3 hours (rehydration period, REP). The subjects ingested test beverages equal to their body weight loss during the first 20 minutes in REP. Blood and urine samples were obtained throughout the experiments to assess the rehydration effect.</p><p><b>RESULTS</b>The change in blood viscosity at a shear rate of 5/s was significantly lower in CE ((-1.66 ± 0.21) mPa×s) in comparison to water ((-0.95 ± 0.26) mPa×s) or tea ((-0.92 ± 0.14) mPa×s) at 60th minute during the REP. The fluid retention rate was significantly greater for CE ((77.0 ± 3.9)%) than water ((61.2 ± 3.4)%) and tea ((60.5 ± 3.7)%) for 3 hours of rest in REP.</p><p><b>CONCLUSIONS</b>The recovery from high blood viscosity induced by dehydration was higher with CE consumption than with water or tea. These results suggest that CE is useful for normalizing increased blood viscosity due to exercise-induced dehydration.</p>

Modulating effects of chlorogenic acid on lipids and glucose metabolism and expression of hepatic peroxisome proliferator-activated receptor-alpha in golden hamsters fed on high fat diet / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To examine the effects of chlorogenic acid (CGA) on lipid and glucose metabolism under a high dietary fat burden and to explore the possible role of peroxisome proliferator-activated receptor-alpha (PPAR-alpha) in these effects.</p><p><b>METHODS</b>Twenty male golden hamsters were randomly divided into CGA treatment group (n=10, given peritoneal injection of CGA solution prepared with PBS, 80 mg CGA/kg body weight daily), and control group (n=10, given PBS i.p. at the average volume of the treatment group). Animals in both groups were given 15% high fat diet. Eight weeks after treatment with CGA, the level of biochemical parameters in fasting serum and tissues and the expression of hepatic mRNA and protein PPAR-alpha were determined.</p><p><b>RESULTS</b>Eight weeks after treatment with CGA, the levels of fasting serum triglyceride (TG), free fatty acid (FFA), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), glucose (FSG), and insulin (FSI) were significantly lower in the GGA treatment group than in the control group. CGA also led to higher activity of hepatic lipase (HL), lower contents of TG and FFA in liver, and lower activity of lipoprotein lipase (LPL) in skeletal muscle. Furthermore, CGA significantly elevated significantly elevated the expression level of mRNA and protein expression in hepatic PPAR-alpha.</p><p><b>CONCLUSION</b>CGA can modify lipids and glucose metabolism, which may be attributed to PPAR-alpha facilitated lipid clearance in liver and improved insulin sensitivity.</p>