Effects of 12 weeks of aerobic exercise plus dietary restriction on body composition,resting energy expenditure and aerobic fitness in mildly obese middle-aged women

This study investigated the effects of 12 weeks of aerobic exercise plus voluntary food restriction on the body composition, resting metabolic rate (RMR) and aerobic fitness of mildly obese middle-aged women. The subjects were randomly assigned to exercise/diet (n = 17) or control (n = 15) groups. The exercise/diet group participated in an aerobic training programme, 45–60 min · day ^–1 at 50%–60% of maximal oxygen uptake (VO_2max), 3–4 days · week^–1, and also adopted a self-regulated energy deficit relative to predicted energy requirements (–1.05 MJ · day ^–1 to –1.14 MJ · day ^–1 ). After the regimen had been followed for 12 weeks, the body mass of the subjects had decreased by an average of 4.5 kg, due mainly to fat loss, with little change of fat free mass (m _ff). The absolute RMR did not change, but the experimental group showed significant increases in the RMR per unit of body mass (10%) and the RMR per unit of m _ff (4%). The increase in RMR/m _ff was not correlated with any increase in VO_2max/m _ff. The resting heat production per unit of essential body mass increased by an average of 21%, but the resting heat production rate per unit of fat tissue mass remained unchanged. We concluded that aerobic exercise enhances the effect of moderate dietary restriction by augmenting the metabolic activity of lean tissue.     

Failure to demonstrate early metabolic changes in weanling growth-retarded hypophagic rats with lesions in the dorsomedial hypothalamic nuclei

Experiment 1: Weanling male rats received bilateral electrolytic lesions in the dorsomedial hypothalamic nuclei (DMNL rats); sham-operated animals served as controls. Rats were killed four hours and three and seven days postoperatively (post-op). Plasma was obtained and epididymal fat pads, diaphragm and liver aliquots were harvested and the in vitro incorporation of U-14C-glucose into CO2, glycogen, lipid and saponifiable fatty acids (FAs) were measured. Body weight, carcass lipid and food intake were significantly lower in DMNL rats than in controls. The only significant lesion-induced metabolic changes were hypoglycemia and greater tracer incorporation into epididymal fat pad lipid and diaphragm glycogen. Both DMNL rats and controls showed similar time courses of tracer incorporation into epididymal CO2 and FAs, diaphragm lipid and liver CO2, glycogen, lipid and FAs. Lesioned rats also showed more pronounced decreases of tracer incorporation from day 0 to day 3 in epididymal glycogen and lipid and diaphragm CO2 and glycogen. These data make it appear unlikely that very early deficits in glucose metabolism are the cause of the growth retardation seen in long-term studies with DMNL rats. The data also demonstrate considerable locus specificity, since weanling rats with ventromedial hypothalamic lesions (VMNL rats) in similar short-term studies have shown dramatic alterations in the above parameters. Experiment 2: Weanling DMNL rats and sham-operated rats were injected via tail vein with tritiated water one hour post-op. One hour after the injection they were decapitated. There were no significant differences between DMNL rats and controls in mumoles tritiated water incorporated into total liver, grams liver tissue, mg liver glycogen and ml or mg plasma glucose.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of tibolone on body composition in postmenopausal women: a 1-year follow up study

Objective: We investigated the effects of 1-year tibolone treatment on body weight, body composition and indices of android obesity in postmenopausal women.

Methods: Forty-four postmenopausal women participated in this open-label controlled study; mean age was 51.8 ± 2.21 years and all women were menopausal for 3.8 ± 1.40 years. Twenty-two of them started taking 2.5 mg tibolone (TIB) daily for 1 year, whereas the remaining 22 served as age-matched controls. All subjects underwent a structured interview, physical examination, body composition measurements performed by dual-energy X-ray absorptiometry (DXA) — Hologic QDR 4500 A, as well as bioelectrical body impedance analysis (BI) — Tanita TBF-215, Japan.

Results: The TIB group did not significantly increase their weight (+0.4 kg), while the non-treated controls increased their mean weight by 1.4 kg (p = 0.046). In the TIB group, DXA showed a non-significant body fat decrease by a mean of 0.5 kg and a non-significant lean mass increase by 0.8 kg, while in the control group, fat mass increased by 1.7 kg (p = 0.032) and lean mass did not change. BI revealed that the TIB group had lost some fat (≈0.6 kg, n.s.) and put some free-fat mass (≈1.0 kg, p = 0.048) without changes in total body water. The control group put on some fat (≈1.1 kg, p = 0.042) and lost some body water (≈0.4 kg, n.s.).

Conclusion: Results from both methods of measuring body composition show a similar trend: a decrease in fat mass and an increase in lean mass in TIB treated subjects. From the body composition perspective, tibolone may be regarded as a preferential alternative to conventional hormonal therapy (HT) in postmenopausal women.     

Hyperthermia and maximal oxygen uptake in men and women

To compare the effect of hyperthermia on maximal oxygen uptake (O_2max) in men and women, O_2max was measured in 11 male and 11 female runners under seven conditions involving various ambient temperatures (T_a at 50% RH) and preheating designed to manipulate the esophageal (T_es) and mean skin temperatures at O_2max. The conditions were: 25°C, no preheating (control); 25, 35, 40, and 45°C, with exercise-induced preheating by a 20-min walk at ~33% of control O_2max; 45°C, no preheating; and 45°C, with passive preheating during which T_es and were increased to the same degree as at the end of the 20-min walk at 45°C. Compared to O_2max (l·min^–1) in the control condition (4.52±0.46 in men, 3.01±0.45 in women), O_2max in men and women was reduced with exercise-induced or passive preheating and increased T_a, ~4% at 35°C, ~9% at 40°C and ~18% at 45°C. Percentage reductions (7–36%) in physical performance (treadmill test time to exhaustion) were strongly related to reductions in O_2max (r=0.82–0.84). The effects of hyperthermia on O_2max and physical performance in men and women were almost identical. We conclude that men and women do not differ in their thermal responses to maximal exercise, or in the relationship of hyperthermia to reductions in O_2max and physical performance at high temperature. Data are reported as mean (SD) unless otherwise stated.     

Perceptual distortion of face deletion by local anaesthesia of the human lips and teeth

As visual guidance of facial movements is impossible, accurate movements for speech and mastication require an established body image that is formed via the information from mechanoreceptors in the skin, mucosa, periodontium, and proprioceptors in the facial and masticatory muscles and in the jaw joints. In this study we aimed to investigate how the acute deafferentation of lips and teeth alters the established image of lips, teeth and the thumb. We used a psychophysical method to determine whether the perceived sizes of the upper lip and front teeth change when the sensory input from the lips and front teeth is fully blocked. We also examined the perceived size of the thumb to test for acute interactions between the thumb and facial structures. Local anaesthetic blocking of upper lip and upper front teeth significantly increased the perceived size of the upper lip by as much as 100% (range 21–100%) in ten out of eleven subjects tested (overall mean 52%; p=0.001). The perceived size of the upper teeth also significantly increased by as much as 155% (range 30–155%) in eight of the eleven subjects during anaesthesia (overall mean 41%; p=0.035). When the region of anaesthesia was increased and both upper and lower teeth and lips were anaesthetised, the perceived size of the upper lip again increased, by 53% (p=0.040), but the change in perceived size of the upper front teeth (18%) was not significant (p=0.206). In both studies there was no change in perceived size of the thumb. The results illustrate the labile central interaction between sensory inputs and the importance of feedback from peripheral afferents in generating the subjective facial image. The timing, level, and area of anaesthesia may be important modifiers of these interactions.     

Effect of exercise on Hepatic cholesterof of rats fed diets high in saturated or unsaturated fats

Summary Rats have been fed diets containing 24.2% coconut or corn oil or an equal mixture of each for 14–18 weeks. Half of the animals in each dietary group were exercised by running in motor-driven work wheels throughout the entire experimental period. During the final 10–14 weeks, these exercised animals ran continuously for 60 min at 1.0 mph or faster each day. Comparisons between sedentary groups revealed that hepatic cholesterol and excretion of digitonin precipitated sterols in the feces increased (P < 0.01) as the per cent of unsaturated fat (corn oil) in the ingested food increased. In contrast, total liver lipid decreased (P < 0.01) as the consumption of corn oil increased. No change in plasma cholesterol occurred in the sedentary rats in response to the three diets. Hepatic cholesterol of the exercised groups was significantly less (P < 0.05–P < 0.01) than that of their respective control groups (same diet). However, the group fed the corn oil diet had a significantly higher (P < 0.01) liver cholesterol after exercise than did the exercised group fed the coconut oil diet. Liver lipid was reduced (P < 0.01) by exercise in the corn oil and mixed corn-coconut oil fed groups. Plasma cholesterol and sterol excretion were unchanged by the exercise program.This investigation supported by Research Grant HE 08262 from the National Heart Institute, National Institutes of Health, U.S. Public Health Service.     

Body weight regulation in ground squirrels and hypothalamically lesioned rats: slow and sudden set point changes

Golden-mantled ground squirrels. Citellus lateralis, have a near annual cycle in body weight. In the present experiments their weights were temporarily forced off the usual levels either by food deprivation during a phase of weight gain or by offering extra palatable food during a phase of weight loss. When these treatments ceased the weights returned to levels appropriate for that time of year rather than to pretreatment values. Therefore the cycle of body weight in uniform and ad lib conditions reflects an underlying cycle in slowly climbing or sliding set points for body weight. In contrast to fattening ground squirrels, lesioned rats in the dynamic phase of hypothalamic hyperphagia did not compensate well for weight losses incurred during food deprivation. Weight gain during the dynamic phase appears to be roughly proportional to the discrepancy between actual and set weights, the latter being suddenly much elevated by the lesion.     

Quality validation of platelets obtained from the Haemonetics and Trima Accel automated blood-collection systems

BackgroundPlatelet transfusion is required to treat haemo-oncology or trauma patients. Platelet apheresis (PA) performed with apheresis equipment has increased rapidly in recent years. Leucocyte-reduced platelet apheresis (LRPA) can reduce the risk of platelet refractoriness and febrile nonhemolytic transfusion reactions (FNHTRs) for transfusion. Accordingly, this study aimed to investigate and compare the platelet metabolic and functional responses between PA performed with Haemonetics and LRPA performed with Trima Accel cell separator.MethodsThe qualities of platelets collected through PA and LRPA were evaluated in terms of visual appearance, morphology, platelet-aggregation changes, metabolic activities, and bacterium-screening test during 5-day storage. Statistical analyses included two-sample t-test and generalised estimating equation(GEE) method.ResultsDuring 5-day storage in LRPA, residual leucocytes were all <1.0×10⁶, and the parameters of platelet function were as follows: platelet aggregated to agonists such as adenosine 5′-diphosphate (ADP) and collagen, and the extent of shape change and pO₂ showed no statistically significant difference between PA and LRPA. The hypotonic shock reaction (HSR) on days 0, 1, and 3 were significantly higher in LRPA than in PA (71.78±6.92 vs. 64.10±7.42; P=0.002; 71.53±8.98 vs. 62.96±9.84; P=0.007; 68.05±7.28 vs. 57.76±6.80; P<0.0001, respectively). Values of mean platelet volume (MPV) were statistically larger in PA than in LRPA on days 0, 1, and 3. On day 5, the swirling score was higher in LRPA than in PA. The mean lactate levels had no statistically significant difference between PA and LRPA. Moreover, no growth was observed through bacterium-screening test conducted on 40 samples.ConclusionComparison of LRPA and PA products collected from the Trima Accel and Haemonetics automated blood-collection systems, respectively, revealed that both products possessed good platelet qualities even though additional processes are needed to reduce leucocytes. Furthermore, investigating the outcomes of other apheresis instruments with focus on the safety of donors, products, and recipients is necessary.     

Dry heat loss in incubator: comparison of two premature newborn sized manikins

Keeping premature newborns warm is crucial for their survival. Their ability to prevent excessive heat loss to the environment and to control their body temperature is limited. The risk of hypothermia is particularly important for low-birth-weight newborns with a large body surface area in relation to their mass of heat-producing tissues. The present study was performed to assess the body heat loss difference between small and large body-size premature newborns using two anthropomorphic thermal manikins of premature newborns of 900 g and 1,800 g (respective body surface areas of 0.086 and 0.150 m²). The dry heat loss from the six body segments of the small manikin (S) was measured and compared with that of the large manikin (L). The two manikins were exposed to five different environmental temperatures ranging between 29 and 35°C in a single-walled, air-heated closed incubator. The magnitudes of heat loss decreased significantly by 20.4% between the two manikins [small manikin 110.1 (44.3) W/m² vs large manikin 87.6 (25.8) W/m², mean values with one standard deviation]. The results obtained from the comparison of the heat loss measures from the two manikins confirm the fact that the heat loss increases with an increase in the ratio of the body surface area to body mass. The thermal manikin appears to provide an accurate method for the assessment of thermal conditions in neonatal care.     

华中地区省会城市青春期青少年体脂率状况及其与血压的关联

目的 了解华中地区青春期青少年体脂率状况以及与血压之间存在的关联关系,为该地区青少年心血管疾病的早期预防提供参考和借鉴。方法 2 019年4—6月在河南、湖南、湖北三省省会城市的15所中学对4 846名初中学生进行生物电阻抗（BIA）的身体脂肪测试和问卷调查及血压测试,通过t检验、χ2检验和logistic回归分析等方法分析体脂肪率与血压偏高之间存在的关联关系。结果 华中地区省会城市青春期青少年血压偏高检出率为10.96%。男生血压偏高检出率为8.96%,女生为13.12%,差异有统计学意义（χ2 = 21.48,P＜0.01）。不同城乡、年龄、BMI和是否遗精/月经青少年血压偏高检出率存在显著差异（χ2 = 7.28、86.98、178.68、45.76,P＜0.01）。青春期青少年体脂率平均为（23.14±9.26）,其中男生为（21.02±10.86）,女生为（25.25±8.13）,差异存在统计学意义（t值 = - 15.248,P＜0.01）。Logistic回归分析显示,与男生体脂率＜P 25者相比较,P25～＜P50、P50～＜P75、P75～＜P90、≥P90者患血压偏高的比例是其3.14（OR值95%CI = 1.76～5.52）、4.05（OR值95%CI = 2.31～7.01）、6.33（OR值95%CI = 3.55～11.17）、12.44（OR值95%CI = 6.97～22.13）倍（P＜0.01）;与女生体脂率＜P 25者相比较,P50～＜P75、P75～＜P90、≥P90者患血压偏高的比例是其2.25（OR值95%CI = 1.45～3.45）、3.29（OR值95%CI = 2.09～5.12）、6.14（OR值95%CI = 3.88～9.64）倍（P＜0.01）。结论 华中地区省会城市青春期青少年体脂率与血压偏高之间存在显著正相关关系,男生关联关系大于女生,今后应保持合理的体脂率,以预防血压偏高的发生。