沉默STAT1基因增强放射抗拒鼻咽癌CNE-2R细胞放射敏感性

目的 研究基因STAT1沉默对人放射抗拒鼻咽癌细胞放射敏感性的影响.方法 慢病毒介导的STAT1基因转染放射抗拒鼻咽癌细胞CNE-2R,荧光定量RT-PCR技术检测沉默效果.MTT法检测转染前后细胞增殖活性,流式细胞技术检测细胞周期及凋亡,克隆形成实验检测转染前后细胞放射敏感性变化.结果 慢病毒转染后放射抗拒鼻咽癌细胞STAT1表达降低(F=429.87,P<0.05)、细胞生长抑制(F3=.88~4.63,P<0.05)、凋亡率增加(F=38.13,P<0.05)、放射敏感性增加(F=252.80,P<0.05)、细胞周期中G₀/G₁、S和G₂/M期未见明显差异(P>0.05).结论 沉默STAT1基因能增加放射抗拒鼻咽癌细胞 CNE-2R的放射敏感性.     

RNA干扰肝癌MHCC97-H细胞N-Ras基因对放射敏感性的影响

目的 探讨RNA干扰(RNAi)N-Ras基因增强人肝癌MHCC-97细胞的放射敏感性.方法 通过构建干扰N-Ras基因siRNA,采用免疫组织化学法、实时荧光定量RT-PCR、Western blot、MTT法观察RNAi前后肝癌MHCC97-H细胞RNA水平、蛋白水平、生长情况等变化,照射后用细胞克隆计数实验检测放射敏感性变化.结果 MHCC97-H细胞株RNAi后mRNA表达抑制率为96.9%±0.159%,RNAi前后差异有统计学意义(t=40.377,P＜0.05),蛋白表达抑制率为89.8%±0.012%,RNAi前后差异有统计学意义(t=31.595,P＜0.05),免疫组织化学显示90%表达被抑制,细胞生长抑制率为21.9%,RNAi前后差异均有统计学意义(F=4.63,P＜0.05).MHCC97.H细胞RNAi后增敏比(SER)=1.15.结论 RNAi肝癌MHCC97-H细胞N-Ras基因可以达到放射增敏的目的.

Abstract：

Objective To investigate the radiosensitivity of silencing N-Ras by RNA interference in hepatoma carcinoma cell MHCC-97.Methods N-Ras RNA interference (RNAi) vector was constructed by using pcDNA 6.2-GW/EmGFP-mir plamid.The RNAi effect was detected by RT-PCR,Western bolt,immunohistochemisty and MTT method.Survival curve for each cell line were obtained by measuring the clone forming abilities of irradiated cell populations.Results After silencing the N-Ras by RNAi,The expression level of N-Ras mRNA,N-Ras protein,immunohistochemisty were decreased 96.9% ±0.159%(t=40.377,P＜0.05),89.8%±0.012% (t=31.595,P＜0.05),90%,respectively,and The survival of hepatoma carcinoma cell MHCC-97 line were inhibited 21.9% (F = 4.63,P < 0.05).Which have significant difference in statistics.The SER of hepatoma carcinoma cell MHCC-97 line after interference was 1.15.Conclusions RNAi targeting silence N-Ras may increase the radiosensitivity of hepatoma carcinoma cell MHCC-97 line.     

Astreinte physiologique des sapeurs pompiers lors de l'approche d'un feu

Introduction. – The present study is a contribution to quantifying constraints experienced by professional and voluntary firefighters when exposed to a fire.Methods and results. – Variation in mean skin temperature and heart rate of professional and voluntary firefighters were measured under a fire condition. Exposition to the heat during firefighting, increases considerably physiological parameters in a few minutes in professional as well as in voluntary firefighters.Conclusion. – These results indicate that the time passed to fight against fire, without risk of hyperthermia is very limited.     

Suivi de l’entraînement de nageurs de haut niveau par questionnaire de fatigue, dosages hormonaux et variabilité de la fréquence cardiaqueTraining follow up by questionnaire fatigue, hormones and heart rate variability measurements

Introduction. – A short questionnaire of fatigue, urinary cortisol/cortisone ratio and heart rate variability were measured in 14 elite swimmers during heavy, light and moderate training periods.Results. – The questionnaire was strongly related to the variations of training and performance (r > 0.70). Correlations were lower with the hormonal ratio and insignificant with the heart rate variability.Conclusion. – The questionnaire and the hormonal ratio were good markers of the variations of training and performance contrary to the heart rate variability.     

Réponses corticotropes à un stress intense en fonction de l'entraînement chez deux souches de rats. Résultats préliminairesCorticotropic responses to acute stress according to exercise training in different rat strains: preliminary results

Aims – Determine the corticotropic responses to acute stress with or without prior exercise training and following the corticotropic phenotype of the rats.Methods and results – Lewis and SHR strains were selected for their opposite corticotropic responsiveness characteristics (high and low in SHR and Lewis strain, respectively). This study shows that exercise training induces opposite adrenal responses in SHR strain and in Lewis strain (which decrease increase its corticosterone concentration, respectively).Conclusion – This suggests that genetic may play an key role in pituitary-adrenal adaptations to exercise training.     

Somatotypes et débit cardiaque chez les handballeurs d'élite

Objective – The aim of this research is to study the relationship between the cardiac output (CO) and the somatotype in elites handball players.Facts – The CO of endomorphs (ENDO) is significantly higher than mesomorphs (MESO) at rest (P < 0,01) and at 70% (P < 0,01). The QO presents a significant correlation with the fat free mass (FFM) in all the population of study (P < 0,001).Conclusion. – This study shows that the FFM could be considered as a determining factor of the variation of the CO between the ENDO and the MESO.     

Aptitudes cardiorespiratoires à l'exercice et fonction musculaire périphérique chez des enfants infirmes moteurs d'origine cérébrale

Introduction. – The aim of this study is to assess the aerobic capacity and the skeletal muscle function (force and muscular endurance of quadriceps muscle) in children with cerebral palsy (CP) compared with healthy children.Synthesis of facts. – In children with CP, the aerobic capacity during exercise is lower compared with healthy children in association with an impaired maximal isometric force and endurance of the quadriceps muscle.Conclusion. – Children with CP have a lower aerobic capacity and an impaired skeletal muscle function compared with healthy children.     

Effet d'une prise en charge pluridisciplinaire sur l'adiposité et la condition physique d'adolescent(e)s obèses

Aim. – To investigate the effects of physical activity and nutritional intake on obese adolescents body mass index (BMI) and physical condition.Methods. – Each month, adolescent BMI and physical condition were determined during 10 months.Results. – BMI was significantly decreased after 10 months in both sexes but did not differ between sexes. Physical condition of adolescents was significantly increased and gender difference appeared. The evolution of adolescent body weight, during the protocol, was not associated with the age of obesity appearance. Also, the number of obese parents did not influence the adolescents body weight decrease.Conclusion. – This study demonstrated that multidisciplinary weight-reducing program presents beneficial effects on health.     

Effets en miroir de l''entraînement et du surentraînement sur la fonction somatotrope et la balance glucidolipidique à l''exerciceEffects out of mirror of the drive and overtraining on the somatotropic function and the glucido-lipidic balance with the exercise

Objective. – To confirm the assumption whereby overtraining would have opposite effects on the utilisation of the substrates and the somatotropic function.Exposed facts. – The drive has different effects according to its characteristics and its level. It seems y to have two types of drive: that which amplify the aptitude to oxidize lipids (low powers) and that which accroit the aptitude to oxidize glucides (high powers and/or intermittent exercise). Overtraining reverses these two effects. The somatotropic axis has an evolution parallel with these processes and seems implied in those.Conclusion. – This diagram deserves to be confirmed by additional studies.     

Effet du déconditionnement suite à une chirurgie du genou sur l'aptitude aérobie

Introduction. – The object of this study consisted in analysing the changes in cardiorespiratory fitness of fourteen sportsmen having undergone a surgical operation following a lesion of the anterior cruciate ligament of the knee.Methods and results. – Two triangular and maximum tests starting from the upper limbs were carried out before and after the operation with 7 days of interval. The results showed that the operation followed by a few days of bed rest generates a fast and significant reduction in the maximum oxygen consumption (–7%, p < 0.05) and peak aerobic power (–8%, p < 0.05).Conclusion. – These results could encourage therapists to propose endurance training during rehabilitation protocols.     

三种蔬菜对土壤中Sr元素富集和转移特性的研究

目的 探索放射性核素⁹⁰Sr在土壤-植物系统中的转移特性,并初步分析植物不同组织对土壤中不同浓度Sr的吸收积累特征.方法 利用稳定性核素⁸⁸Sr替代放射性核素⁹⁰Sr进行室内盆栽种植小白菜、芹菜和萝卜的实验.采用电感耦合等离子体发射光谱法(ICP-AES)测定上述3种蔬菜和土壤中Sr的浓度,并计算上述3种蔬菜根部及茎叶部对Sr的转运系数(TF)及富集率(CR),进而研究Sr在土壤-植物系统中的转移特征.结果 土壤中Sr浓度对于蔬菜的不同组织具有显著影响(F=5.90~139.39,P<0.05).在398.33、477.99和557.57 mg/kg的土壤Sr浓度条件下,小白菜、芹菜和萝卜不同组织Sr浓度均高于对照组(t=-10.49~7.41,P<0.05).除了芹菜茎部之外,3种蔬菜的其他组织与实验土壤中Sr含量呈正相关关系(r=0.88~0.99,t=7.41~15.96,P<0.05).小白菜和萝卜各组织样本的转运系数(基于干重)>1,且小白菜和萝卜中的富集率表现为:茎叶部>根部(F=8.22、91.49,P<0.05).结论 3种蔬菜对Sr均有一定的富集作用.     

水平射野对肺癌调强计划结果的影响研究

目的 探讨水平方向射野对肺癌调强计划结果的影响.方法 收集肺癌患者18例,其中左肺癌患者10例,右肺癌患者8例,设计普通调强(IMRT计划)和在普通调强基础上添加一个水平方向射野(H-IMRT计划)的计划,比较机器跳数、子野数及靶区和危及器官(OARs)的剂量分布.结果 两种计划PTV的D_max、D_min及D_mean,患侧肺的V₃₀和D_mean,健侧肺的V₂₀ 和V₃₀,全肺的V₃₀差异均无统计学意义.与IMRT计划相比,添加水平射野后,PTV的均匀性(HI)及适形度(CI)都有显著提高(t=-9.33、10.88,P<0.05);肺的其他剂量指标均变差(t=-1.55~-7.58,P<0.05);心脏的保护更优(t=1.84~3.99,P<0.05);MUs及子野数量降低(t=12.57、3.19,P<0.05).结论 在肺癌的IMRT治疗中,添加水平射野可以改善靶区的剂量分布,但会使肺的低剂量照射体积增加,无益于肺的保护.     

Détermination de l'insulin-like growth factor-I, du lactate et du glucose par microdialyse musculaire au cours d'un exercice d'électrostimulation modéré

Introduction. – The impact of low intensity light neuromuscular electrostimulation (14 Hz, 30 mA) of the vastus lateralis was assessed through interstitial microdialysis measurement of free Insulin-Like Growth Factor-I, glucose and lactate during the stimulation (45 minutes) and recovery (40 minutes) periods in 3 healthy subjects.Results. – Muscular uptake of glucose was immediate, while delayed decrease of lactate production was observed. Free Insulin-Like Growth Factor-I was decreased during recovery.Conclusion. – These data suggest that a low intensity of neuromuscular electrostimulation determines a metabolic activation of the muscle. That activation spreads to the recovery period.     

Le surentraînement : place de l'interrogatoire dans le diagnostic

Objectives. – To provide a practical guideline of the medical interview to sport physicians in order to facilitate the early detection and the diagnosis of the overtraining syndrome.Methods. – The group proposes an analytic process in four successive steps, to ensure and characterize the long term alteration of sport performance, to characterize the fatigue and look for an underlying disease, to assess the presence of physical and psychological specific symptoms, to search for favouring factors and/or triggers.Conclusion. – The working group proposes that the diagnosis of overtraining can be considered if the alteration of sport performance is associated with at least 4 physical and 4 psychological symptoms with a marked loss of shape but without any underlying disease.     

Effets de l'entraînement sur les potentiels aérobie et anaérobie de jeunes nageurs. Exercice réalisé avec les brasEffect of training on aerobic and anaerobic capacity in young swimmers. Exercise performed with arms

Aims – Investigate the influence of exercise training on the aerobic and anaerobic capacities of young swimmers.Methods – Ten male swimmers aged 15.2 ± 3.8 years participated: five sprint specialists and five middle-distance specialists. Each subject performed, an arm ergocycle, two laboratory tests, a maximal incremental exercise test and a force–velocity test, once in February (T1) and then again in June (T2).Results – For all subjects combined (n=10), the results showed a significant increase in maximal anaerobic power (p < 0.01) between T1 and T2. Aerobic capacity did not change significantly between the two tests in either group.Conclusion – This study demonstrates the interest of evaluating aerobic and anaerobic capacity in young swimmers during arm exercise. The change in results over the 5-month period between the two tests indicates the importance of scheduling exercise tests during the course of athletic training programs.     

Le « syndrome des jambes lourdes » chez les athlètes surentraînés est-il le reflet de désordres hémorhéologiques ?Is the feeling of heavy legs in overtrained athletes related to impaired hemorheology?

Introduction. – The aim of this work is to evaluate if the feeling of heavy legs in athletes is correlated with overtraining syndrome-related hemorheological disturbances.Results. – The subjects who quoted the item: “I have the feeling of heavy legs” had higher plasma viscosity and higher red cell aggregation parameters. The overtraining score was correlated positively with plasma viscosity, and aggregability parameters. The feeling of heavy legs was correlated with plasma viscosity and aggregability.Conclusion. – These findings suggest that the feeling of heavy legs in overtrained athletes is related to overtraining syndrome-related hemorheologic disturbances, namely mild plasma hyperviscosity and mild erythrocyte hyperaggregability.     

Composition corporelle et densité minérale osseuse chez des garçons et des filles prépubères : effet de 13 semaines d'entraînement en endurance

Aim. – To investigate the effect of an endurance training program, on the bone mineral density and body composition of prepubertal boys and girls. The Regional Bone Mineral Density and Body.Materials and methods. – Composition were measured by dual energy X-ray absorptiometry (DXA, Hologic QDR 1000/W, Hologic, Waltham,MA) and maximal oxygen uptake by a continuous and progressive exercise test to exhaustion.Results. – A 13-week endurance training program is effective for increasing maximal oxygen uptake, but no sufficient to increase the Bone Mineral Density and to change the Body Composition in healthy prepubertal children.     

Influence de l''hydratation sur la sécrétion d''hormone de croissance induite par l''exerciceHydration influence on exercise-induced growth hormone secretion

Aim – Study was then to investigate hydration influence on exercise-induced GHh secretion.Methods and results – Seven healthy men underwent a submaximal rectangular cycling exercise for 30 minutes to 150 watts during two sessions. A first one without any water intake and a second one with ingestion of spring water corresponding to the volume of water lost during the first session. Plasma volume decrease was significantly higher during the first session (p < 0.05). Total GH secretion was significantly lower during this session (p < 0.05).Conclusion – A moderate dehydration decreases exercise-induced GH response. Thus, hypovolemia may exert a negative feed back on GH secretion, during exercise.     

Profil isocinétique des muscles fléchisseurs et extenseurs du genou dans une population d'athlètes sauteurs

Introduction. – This study explored concentric and eccentric profile of knee musculature in a jumpers population. Relationships between isokinetic assessment and field tests performances have also been explored.Materials. – Jumpers population presented higher knee flexors performances in concentric and eccentric mode and superior knee extensors strength in eccentric. Significant correlations between isokinetics and field tests results were exclusively observed with athletes quadriceps performances. A very high correlation (r = 0.93) was found between the second bound relative performance of the ten multijumps test and eccentric quadriceps relative peak torque.Conclusion. – Jumpers training may favour a specific muscular development. The knee extensors eccentric strength may be a major factor in the athletic performance.     

Le questionnaire de surentraînement de la Société française de médecine du sport : reproductibilité à court termeOvertraining questionnaire of the Société française de médecine du sport (French Society of Sport Medicine): short term reproducibility

Purpose. – To assess the short-term stability, over time, of a slightly modified version of the overtraining questionnaire proposed by the SFMS.Methods. – Three or 7-day test–retest of the questionnaire was completed in 30 high level athletes. In a first stage analysis, the score obtained during the first test was compared to and correlated with that obtained during the second one. Then, in a second stage analysis, the individual reproducibility of each item was assessed using a similitude index: a value of 100% meant that all the athletes gave an identical response for the two trials.Results. – Scores were not different between the two tests and intra-class correlation coefficients were r = 0.82. Overall reproducibility of the similitude index was quite good even if six items of 52 displayed a lower similitude index (around 80%).Conclusion. – The short-term reproducibility of the overtraining questionnaire is quite good. This result reinforces its reliability and warrants its use in a longitudinal follow-up framework aimed to detect precociously an overtraining syndrome.