Thermoregulatory responses to cold during a 7-week acclimatisation process in rabbits

A group of six rabbits reared at +20°C ambient temperature was adapted to moderate cold by housing for seven weeks at +10°C. Rectal and skin temperatures, metabolic heat production and respiratory evaporative heat loss were recorded continuously over 1 h for each animal on 3 days per week in the climatic chamber.There was no significant change either of rectal or of ear skin temperature during the acclimatisation process. On the other hand, metabolic heat production was progressively reduced (20% in the 7th week). Slight changes of mean skin temperature and respiratory evaporative heat loss could not account for compensation. Therefore it must be concluded that both adaptive improvement of peripheral insulation and reduction of heat production were achieved during the acclimatisation process. Both processes together ensure that deviations of core temperature are minimal. The possible origin of the functional adaptive effects is discussed. The results are in full agreement both with former neurophysiological results and with system-theoretical considerations of adaptive processes.Dedicated to the 60th birthday of Professor Dr. Kurt Brück     

Detection and analysis of gastrointestinal sounds in normal and small bowel obstructed rats

This study is aimed at detecting gastrointestinal sounds (GIS) and correlating their characteristics with gastrointestinal (GI) conditions. The central hypotheses are that GIS generation depends on the motility patterns and the mechanical properties of the gut, and that changes in those result in measurable differences in GIS. An animal model which included both healthy rats and those with small bowel obstruction (SBO) was developed. The acoustic bursts, of GIS were detected by amplitude thresholding the signal envelope. Three methods of envelope estimation were proposed and evaluated. Envelope estimation using a Hilbert transform was found to produce the best results in the current application. The duration and dominant frequency of each detected GIS event was estimated and clear differences between healthy and diseased rats were discovered. In the control state, GIS events were found to consistently be of relatively short duration (3–65ms). Although the majority of events in the SBO state had similar short duration, infrequent longer events were also detected and appeared to be pathognomonic. Long duration events (>100 ms) occurred in each of seven obstructed, but in none of 14 non-obstructed, cases (p<0.001). It is concluded that GIS analysis may prove useful in the non-invasive, rapid, and accurate diagnosis of SBO.     

Influence of sympathectomy on body weight of rats given chow or supermarket diets

Rats that were neonatally sympathectomized with guanethidine (GUA) and given access to a four-component supermarket diet (SD) when either adolescent or adult gained weight at the same rate as controls. Adrenodemedullation (MDL) of adults, either alone or in combination with GUA treatment, also failed to influence the development of dietary obesity. Neonatal sympathectomy induced small changes in caloric consumption and diet preferences. These results question the notion that the sympathetic nervous system (SNS) is an essential contributor to the control of body weight and the development of dietary obesity.     

不同导联系统记录体表心室碎裂电位效果对比研究

本文分别应用标准１２导联系统，Ｆｒａｎｋ正交导联系统和改良Ｆｒａｎｋ正交导联系统记录健康人３６例、陈旧性心肌梗塞４２例的心室碎裂电位，通过分析这些导联系统中相互垂直或近似垂直的导联上ＶＦＰ的形态，数量关系，发现改良Ｆｒａｎｋ正导联系统记录ＶＦＰ较其它导联系统更科学，合理，且操作方便。     

Laterality of Body Focus and Digital Skin Temperature in Patients with Raynaud''s Disease

The purpose of the present study was to assess the relationship between lateralization of body image and right versus left vasomotor activity. Fifteen right-handed female patients suffering from idiopathic Raynaud's disease demonstrated a relationship between the extent of right lateralization of body image and bilateral digital skin temperature during a controlled temperature stress test. In addition, subjects showing a reliable right side awareness demonstrated more unilateral vasospastic attacks in their right hand than their left hand white subjects showing no clear right lateralization by body image reported more left hand attacks than right hand attacks. These results were taken as consistent with previous work on the relationship between skin conductance and lateralization of body image.     

妊娠前不同体重指数与围产结局的关系研究

目的研究妊娠前不同体重指数对围产结局的影响。方法回顾性分析2005~2007年在我院分娩的单胎妇女238例,按妊娠前体重指数(BMI)分为BMI在19.8~23.9的正常BMI组、BMI 24~27的高BMI组和BMI≥27的肥胖组。新生儿体重≥4000g为巨大儿。比较正常BMI组、高BMI组和肥胖组的围产结局。结果全部资料共有238例,其中正常BMI组182例,高BMI组117例,肥胖组56例,巨大儿的发生率分别为10.4%、19.6%、28.6%,妊娠期高血压病、妊娠期糖尿病、羊水过多的风险随妊娠前BMI增加而上升,早产、剖宫产、新生儿病率的发生率亦随妊娠前BMI增加而升高,差异有显著性。结论妊娠前异常的母亲体重指数高度影响巨大儿的发生率;随妊娠前BMI增加不良围产结局的风险增加。     

Lipid metabolism during exercise I: Physiological and biochemical characterization of normal healthy male subjects in relation to their physical fitness

Summary On the basis of maximal oxygen uptake ( O₂ max) 18 normal, healthy men were divided into two groups of equal size: moderately trained subjects (MTR) each having O₂ max below 65.0 ml·min^–1·kg^–1 body weight (54.0±8.3) and well trained subjects (WTR), whose O₂ max exceeded 65.0 ml·min^–1·kg^–1 body weight (69.2±4.1). The WTR group had slightly (non significant, n.s.) higher percentage of slow twitch, oxidative (SO) fibers in M. vastus lateralis and higher (n.s.) activities of cytochrome c oxidase (CytOx), succinate dehydrogenase (SDH), 3-hydroxyacyl-CoA-dehydrogenase (HADH), and citrate synthase (CS), while lactate dehydrogenase (LDH) activity was lower (n.s.). In the MTR group only, the SO-%, and the activities of CytOx, SDH and HADH correlated positively with O₂ max, and LDH negatively with O₂ max. These correlations were not significant in the WTR group possibly because of the adaptations produced by training in this group. Multiple regression analysis was used to elucidate the best combination of variables to explain the variance in O₂ max. The best model consisted of the sum of relative activities of oxidative muscle enzymes (CytOx, SDH, HADH, CS), muscle LDH activity, body fat content (% F) and lean body mass. This model explained 69% of the variance in O₂ max; and of the individual variables % F was of utmost importance.     

Estradiol and insulin: independent effects on eating and body weight in rats.

The effects of ovariectomy and estradiol replacement were determined in streptozotocin-diabetic female rats maintained on daily injections of protamine zinc insulin. Similar changes in food intake and body weight in these animals and in nondiabetic control animals indicate that the effects of estradiol on these measures are probably not dependent on changes in pancreatic insulin secretion. Acute and chronic insulin challenges in ovariectomized rats maintained on estradiol benzoate, nafoxidine or oil were also examined. The effects of insulin were not attenuated by prior estrogen conditioning, and there was no evidence of insulin resistance. These experiments suggest that the effects of estradiol on body weight and food intake in female rats are not dependent upon altered insulin levels nor attenuation of the effects of insulin. Estradiol may exert its influence on eating and body weight via separate and possibly more direct pathways. The data also are consistent with the suggestion that ovariectomy-induced and hypothalamic obesities are separate phenomena.     

The Psychological Significance of Task-Induced Tonic Changes in Somatic and Autonomic Activity

Two experiments tested the view that task-induced autonomic-somatic gradient parallelism does exist and that the steeper the physiological gradients, over the course of a task, the more involved the subject and the greater the effort. Thirty-three male subjects performed easy and difficult versions of a continuous reaction time task. In both experiments the difficult task prompted steeper electromyographic (EMG) activity gradients than did the easy version. Scores on heart rate (HR) and skin conductance did not show clear gradients. However, task-dependent effort was positively related to the magnitude of the initial HR acceleration and to the steepness of the EMG gradient. The autonomic-somatic coupling hypothesis of Obrist did not explain the results. Instead, evidence for ventilatory-somatic parallelism was found.