Collagen from Turkey (Meleagris gallopavo) tendon: A promising sustainable biomaterial for pharmaceutical use

Collagen is the major fibrillar component and protein in both human and animal connective tissue. It is applied in medical preparations, e.g. wound dressings and tissue engineering. Meat and poultry production industries result in large amounts of organic waste, rich in collagen. Our aim was to isolate and characterize pepsin soluble collagen from turkey tendon. Structural analysis indicated the presence of α-chains from both collagen type I and III, β-dimers and γ-trimers, consistent with the estimated molecular weight of 477.3 kDa. Circular dichroism spectroscopy confirmed an intact triple helix. The collagen demonstrated excellent thermal stability, with denaturation temperatures (T_max) at 38.5 °C and 44.5 °C and partial refolding after extensive heating. Biocompatibility was confirmed through cell viability tests. The collagen was investigated for its potential drug carrier ability. Freeze dried collagen scaffolds containing prilocaine hydrochloride and riboflavin were prepared in the presence or absence of photo-crosslinking. Photochemical crosslinking was confirmed by SEM and enhanced mechanical properties were observed. Scaffolds had a significant slower in vitro release of the active ingredient than a reference solution. Altogether, our study suggests collagen from turkey tendon as a promising sustainable biomaterial for pharmaceutical use.     

Long-term and short-term tolerable work-time in a hot environment: The limit values verification

A group of four efficient mine rescuers at the age of 25-35 years were exposed to a load at a cyclo-ergometer (stage A and B) and a hand ergometer (stage E) in a climate chamber. The total period of work of 120 min was divieded into four work intervals, 30 min each. There were 5-min breaks between the individual intervals. The load at the ergometer was selected in the range of 25-150 W, Tg = 20-40 C, rh = 40-80% and va = 0.2-1.5 m.s-1. The thermal resistance of the working suit was 0.65 clo in the stage A, 1.07 clo in the stage B and 0.81 clo in the stage E. A total of 200 experiments with 50 combinations of the work and climate load were made. Heart rate, oxygen consumption, carbon dioxide production, body temperature, skin temperature, water loss by sweating and perspiration, dry and web bulb air temperature, air velocity and globe temperature were measured during the experiments. The expected production of sweat (SR) and the amount of accumulated heat in the body (Qmax) were calculated for each combination of the work-climate conditions by a computing programme ISO 7933:1989 as well as by our own programme.A good agreement was reached between the measured and predicted SR values, calculated by the ISO programme ( r = 0.871) as well as between the values calculated by the two programmes, respectively ( r = 0.985). The experimental results have shown a good agreement between the predicted and actually measured values of temperature of the body core as an index of short-term tolerable climate load. The values of short-term tolerable time of work calculated at the level of the amount of accumulated heat in the body of 50 W.h.m-2 resulted in the increase of body core temperature by 0.8-1.0 K. The values of heart rate mostly did not exceed 140 min-1, reaching in exceptional (three) cases slightly values above 150 min-1. The authors recommend to limit long-term workheat (climatic) load during a higher metabolic rate ( N > 80 W.m-2 include basal metabolic rate) or acclimatized males and females by the sweat rate SR = 270 g.h-1.m-2, of non-acclimatized persons SR = 206 g.h-1.m-2. The limit for low metabolic rates * M 80 W.m-2) for non-acclimatized and acclimatized persons is proposed for long-term tolerable load SR = 147 g.h-1.m-2. Short-term tolerable load by heat storage within organism for all categories is proposed Qmax= 50 W.h.m-2.     

Resting energy expenditure in cirrhotic patients with and without hepatocellular carcinoma

BACKGROUND The diagnosis of malnutrition in patients with independent hepatocellular carcinoma(HCC)varies from 20%to 50%,is related to important complications and has a direct impact on the prognosis.Determination of the resting energy expenditure(REE)has become an important parameter in this population,as it allows therapeutic adjustments to recover their nutritional status.The REE in cirrhosis,with and without HCC,is not clearly defined,and requires the identification and definition of the best nutritional approach.AIM To evaluate the REE of patients with cirrhosis,with and without HCC.METHODS This is a prospective observational study evaluating the REE of 118 patients,33 with cirrhosis and hepatocellular carcinoma and a control group of 85 patients with cirrhosis without HCC,using indirect calorimetry(IC),bioimpedance,and predictive formulas.RESULTS The REE determined by IC in cirrhotic patients with HCC was 1643±364 and in those without HCC was 1526±277(P=0.064).The REE value as assessed by bioimpedance was 1529±501 for those with HCC and 1660±385 for those without HCC(P=0.136).When comparing the values of REE determined by IC and predictive formulas in cirrhotics with HCC,it was observed that only the formulas of the Food and Agriculture Organization(FAO)/World Health Organization(WHO)(1985)and Cunningham(1980)presented values similar to those determined by IC.When comparing the REE values determined by IC and predictive formulas in cirrhotics without HCC,it was observed that the formulas of Schofield(1985),FAO/WHO(1985),WHO(2000),Institute of Medicine(IOM)(2005)and Katch and McArdie(1996)presented values similar to those determined by IC.CONCLUSION The FAO/WHO formula(1985)could be used for cirrhotic patients with or without HCC;as it is the one with the values closest to those obtained by IC in these cirrhotic patients.     

Glucocorticoids enhance and suppress heart rate and behaviour in time dependent manner in greylag geese (Anser anser)

Stress responses involve autonomic, endocrine and behavioural changes. Each of these responses has been studied thoroughly in avian species, but hardly in an integrative way, in free-living birds. This is necessary to reveal the temporal dynamics of the stress response. Towards that goal, we recorded heart rate (HR) and behaviour in free-ranging male greylag geese (Anser anser) simultaneously over 2 h. The geese were subjected to (a) unmanipulated control condition, (b) capture, handling and injection of ACTH, and (c) capture, handling and injection of a saline solution (SHAM). Fecal samples for the non-invasive determination of immuno-reactive glucocorticoid metabolite (BM) concentrations were collected for 7 h thereafter. The SHAM control caused a significant BM increase, a transient increase in HR, an initial increase of preening behaviour and a delay in feeding. ACTH treatment, relative to SHAM, produced significantly higher BM concentrations, and activation of “displacement behaviours” such as wing flapping, body shaking and preening. Also, feeding activity as well as resting was postponed and/or lower for a longer period of time after ACTH than after SHAM. ACTH injection had a greater effect than SHAM injection on HR increase in the first hour, but particularly on HR decline in the second hour following the injection. Hence, glucocorticoids had time- and dose-dependent stimulatory and suppressive effects on cardiovascular activity and behaviour. HR dynamics after ACTH actually matched with behavioural dynamics: both were first enhanced and later suppressed, which is in alignment with adaptive stress management involving the fight-flight response and recovery from stress, respectively.     

Highly producible method for determination of occlusal vertical dimension: relationship between measurement of lip contact position with the closed mouth and area of upper prolabium

Purpose

A new method inducing the physiologic rest position of the mandible using the lip contact position with the closed mouth have compared with those obtained using conventional methods of placing the mandible in the physiologic rest position.

牵引复位联合前路减压内固定治疗低位颈椎骨折脱位的疗效分析

目的探讨牵引复位联合前路减压内固定治疗低位颈椎骨折脱位的疗效。方法对2007年10月至2010年10月22例低位颈椎骨折脱位患者,第一步在局部麻醉下行颅骨牵引术,第二步在牵引复位情况下,行前路减压内固定术。结果该组病例术后随访12个月以上,X线片显示骨折脱位均复位,颈椎的正常序列及生理弧度恢复,植骨全部融合,无内固定断裂及松动。按Frantgkel分级,显效f降低2级）6例,有效（降低1级）13例,无效3例。结论在颈椎牵引复位的基础上行前路减压植骨融合内固定是治疗低位颈椎骨折脱位的有效方法。     

静态心肌灌注-代谢显像评价心肌梗死后经冠状动脉介入骨髓干细胞移植治疗的价值

目的:应用心肌灌注-代谢显像评价心肌梗死(AMI)后经冠状动脉介入移植治疗的疗效。方法:应用单光子发射型断层扫描(SPECT)静态心肌灌注代谢显像对比观察经冠状动脉成形术(PCI)+支架(stent)+心肌骨髓干细胞移植(MBMC)前后的心肌梗死区心肌血流灌注和代谢变化。结果:介入移植治疗前灌注缺损106节段,代谢缺损80节段;介入治疗后灌注缺损84节段,代谢缺损66节段,治疗前后灌注代谢差异无统计学意义(χ2=0.033,P>0.05);介入移植治疗前后人均灌注缺损分别是(3.13±1.14)节段和(2.54±1.30)节段,2组差异有统计学意义(P=0.0005);介入移植治疗前后人均代谢缺损分别是(2.42±1.28)节段和(2±1.28)节段,2组差异有统计学意义(P=0.004)。介入移植治疗后定量分析靶心图灌注显像的总记分(SPS)、代谢显像的总记分(SMS)以及严重度记分(SSS)较治疗前均有下降,但无统计学意义(P=0.184,P=0.608,P=0.166)。结论:静态心肌灌注-代谢显像是观察经冠状动脉介入移植治疗AMI疗效的一种方法。     

Effect of increased blood fluidity through hemodilution on coronary circulation at rest and during exercise in dogs

Summary Coronary flow and myocardial oxygen consumption were measured in conscious dogs at rest and during two levels of submaximal treadmill exercise (3 and 7 km/h at 15% grade, respectively) during adaptation to progressive hemodilution with dextran 60. At rest coronary flow increased to more than seven-fold with diminishing hematocrit to 12.5% in order to cover myocardial oxygen consumption which increased from 6.5±0.3 ml/min· 100 g at hematocrit 47.5% to 13.5±0.8 ml/min· 100 g at hematocrit 12.5%. The dilatory capacity of the coronary vessels, estimated from the reactive hyperemia after a 12 sec occlusion of the left circumflex coronary artery, dropped from 602% at control to 45% at lowest hematocrit levels.During the superimposed stress of exercise coronary flow and myocardial oxygen consumption increased further, so that the dilatory capacity of the coronaries was exhausted at hematocrit levels between 16 and 22%.Myocardial oxygen consumption per unit of oxygen delivered to peripheral tissues increased substantially with progressive hemodilution. In the presence of the reduced arterial oxygen content the augmented myocardial oxygen demand limits the overall adaptability to hemodilution by an exhaustion of the coronary dilatory capacity.Supported by Deutsche Forschungsgemeinschaft.     

山东省大中小学生体育锻炼态度及相关作息情况调查

目的了解山东省大中小学生体育锻炼及相关作息情况，探讨学生体质下降的原因，为采取相应干预措施提供依据。方法在参加2005年学生体质健康调研的学校中，随机抽取4029名大中小学生和184名体育教师进行问卷调查。结果学生对体育锻炼的重要性都持肯定态度，多数学生喜欢上体育课．愿意参加学校组织的体育活动；但愿意参加长跑和力量性锻炼的学生所占比例较低。中学生课余作业时间较长，体育锻炼和睡眠时间较少，学习负担较重。学生不积极参加体育锻炼的原因主要是怕累、怕吃苦。结论应减轻学生的学习负担，改进体育教学。加强学生意志的磨练．保证足够的体育锻炼时间和强度。     

Cerebral malaria in inbred mice. I. A new model and its pathology

Plasmodium berghei ANKA was tested for its usefulness as a model for cerebral malaria in inbred mouse strains A, A2G, A/J, C57L, SJL/J and SWR. A suitable model was obtained in A or A/J strain mice. Mortality was 100% after five to eight days with brain haemorrhages occurring terminally. The histopathology is described. The model was stable after six blood passages at 5- to 7-day intervals. Chloroquine abolished the haemorrhages and no intercurrent viral or blood protozoal infections were detected.