The influence of physical activity and fractures on ultrasound parameters in elderly people

A fluorine-18-labeled analog of the potent nicotinic agonist epibatidine is a candidate radioligand for positron emission tomographic (PET) studies of nicotinic acetylcholine receptors (nAcChR). Following intravenous administration of [18F]exo-2-(2'-fluoro-5'-pyridinyl)-7-azabicyclo[2.2.1]heptane (NFEP), high uptake in thalamus was visualized in sections of mouse and rat brain by autoradiography using a phosphor imaging device. Binding of [18F]NFEP to rat thalamic homogenate was consistent with a single class of binding site with a Kd value of 71 pM. In vitro autoradiography of thaw-mounted sections of human thalamus revealed a heterogeneous pattern of binding; Bmax values for ventrolateral nucleus, insular cortex and dorsomedial nucleus, and internal capsule were 20, 8, and 3 pmol/cc of tissue, respectively. However, similar Kd values close to 50 pM were calculated for all regions. These studies support the suitability of [18F]NFEP as a radioligand for PET studies of nAcChR in the living human brain.     

Impact of physical activity and sport on the immune system

This review describes how exercise and physical training affect the immune system. Although many immune functions are stimulated by moderate physical activity, more vigorous effort and periods of heavy training suppress various immune response parameters. Experimental studies from our own laboratories and elsewhere illustrate that cellular infiltration of the active muscle is accompanied by phagocyte activation, suppressed NK-cell function, impaired lymphocyte proliferation, decreased in-vitro immunoglobulin production, pro-inflammatory eicosanoid release, cytokine cascade activation, and altered expression of cytokine receptors. Examples cover deliberate heavy training; single bouts of fatiguing, submaximal work; repeated bouts of exercise; and ultra-long distance athletic events. In young adults, age, environment, and light physical training do not change immune-response parameters. Parallels between immune impairment after vigorous exercise and reactions to surgical sepsis are noted. Vigorous exercise probably induces subclinical muscle injury and an associated inflammatory response. Heavy exercise may be a useful experimental model for developing more effective treatments for sepsis. For protection average athletes may take the anti-oxidant vitamins C and E and non-steroidal inflammatory drugs, if the muscles show signs of an inflammatory reaction. Top-level athletes have received immunoglobulin preparations.     

The influence of physical activity on fatigue in patients with ESRD on hemodialysis

This study examined the relative influence of anemia, nonspecific symptoms and physical activity on fatigue in 43 patients with end stage renal disease on chronic hemodialysis. We found that low levels of physical activity and frequent symptoms were related to high levels of fatigue. Degree of anemia was not related to level of fatigue. Inactivity contributed to fatigue scores more than symptoms.     

Effects of physical activity on lipids and coagulation

In order to evaluate the effects of physical activity on seric lipoproteins and coagulation parameters, an 8-week clinical trial was performed. Fifteen healthy young subjects (average age 23 years) with no history of previous agonistic physical activity, entered the study. Each subject underwent a physical programme consisting of three times a week bicycle ergometer exercise with progressive increases in work rate by using stages of 3 min duration until the 85% of the predictive heart rate was reached. Each individual was subjected to four blood drawings according to the following schedule: at the beginning of the study, after 4 weeks, after 8 weeks (at the end of the programme) and 4 weeks after the interruption of training. As far as the seric lipoproteins are concerned, the following parameters were monitored: total cholesterol, HDL-C, LDL-C, VLDL-C, triglycerides, Apo-A1, Apo-B100, NEFA and phospholipids. On the other hand the following coagulation parameters were monitored: fibrinogen PT, aPtt, coagulation factors (II-XII), red cells, leucocytes, platelets, hemoglobin and hematocrit. From the analysis of the data, the following statistically significant results were observed: HDL-C increased by 14%, LDL-C decreased by 13%, Apo-A1 increased by 6%, fibrinogen increased by 31.7%, Ptt decreased by 3.7% and leucocytes increased by 15%. Four weeks after exercise was terminated, all monitored parameters turned into the basal range. Our data seem to demonstrate a positive effect of physical exercise on seric lipoproteins in the short period. Nevertheless they provide evidence of an hypercoagulability condition demonstrated by the important fibrinogen increase and the Ptt decrease.     

Effects of physical activity on preterm birth

The authors conducted a cohort study of low income women to determine the effect of physical activity on the risk of preterm birth. Women were sampled prenatally from four clinic sites and were scheduled for delivery at the University of Maryland Medical Systems (UMMS). Women who delivered infants at UMMS but who had received no prenatal care were also eligible. Preterm delivery was defined as a delivery prior to 37 completed weeks gestation. After adjusting for confounders, the odds of preterm delivery were increased for women who climbed stairs > or = 10 times per day (odds ratio (OR) = 1.60, 95% confidence interval 1.05-2.46) and for women who engaged in purposive walking > or = 4 days per week (OR = 2.10, 95% CI 1.38-3.20). Leisure-time exercise (> or = 60 days in the first and second trimesters combined) had a protective effect on preterm delivery (OR = 0.51, 95% CI 0.27-0.95). Television viewing had a U-shaped relation with preterm delivery (ORs (95% CI): < 15 hours, 2.09 (1.21-3.61); 29-42 hours, 1.50 (0.84-2.67); > 42 hours, 3.05 (1.75-5.40)). While the results support current recommendations regarding leisure-time activities, activities of daily living appear to increase risk of preterm delivery among low income women. These findings and those for television watching warrant further investigation.     

The influence of age on the canine immune system

Immune function was assessed in a group of 47 Labrador Retrievers, ranging in age from 0.8 to 11.5 years, in order to establish baseline data on canine immunosenescence. Natural killer cell activity, lymphocyte subset distributions, antibody production, and mitogen-induced lymphoproliferative responses, all of which have been demonstrated to undergo age-related changes in humans and mice, were chosen as indicators of immune function. Dogs were categorized by age as young (mean 2.4 years), middle-aged (mean 5.8 years), and old (mean 9.1 years). Natural killer cell activity was not affected significantly by age. Lymphocyte subset analysis revealed a significant age-related increase in the percentage of cells staining with a pan T-cell reagent, accompanied by a corresponding increase in the percentage of CD8 cells from youth to middle age. An age-related decrease in the percentage of B-cells was observed concomitant with the increases in T-cell percentages. A gender-related difference in pan T-cell distribution was also observed, with females having a higher percentage than males. Lymphoproliferative responses of both young and middle-aged dogs to the mitogens concanavalin A, phytohemagglutinin, pokeweed mitogen, and staphylococcal enterotoxin B were significantly higher than those of old dogs. In general, the mitogen responses of male dogs were affected more dramatically by age than those of females. A significant age-related decline in in vivo antibody responses to the protein antigen, keyhole limpet hemocyanin, was not observed, although the mean titers of the young dogs were higher than those of the old.     

Effects of source expertise and physical distance on minority influence.

The treatment of source strength and immediacy distinguishes social impact theory from other theories of social influence. The present study examined the effects of source expertise (e.g., strength) and physical distance (i.e., immediacy) on minority influence. Groups (N?=?40), consisting of 2 naive research participants and 1 confederate who argued for a minority position, provided ratings for 40 hypothetical graduate school applicants. The confederate was seated either 4 ft (1.2192 m; high immediacy) or 10 ft (3.048 m; low immediacy) from the other group members and presented himself as either a senior who had recently applied to several graduate programs (high strength) or as a freshman (low strength). The confederate exerted more influence in the high-strength condition than in the low-strength condition, but only when immediacy was low. The implications of these findings for social impact theory and for future research and practice are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exercise and physical health: cancer and immune function

Over the last decade, there has been accumulating epidemiological data suggesting that exercise may decrease the risk of cancer, particularly colon cancer. However, exercise appears unrelated to rectal cancer risk. With regard to other cancers, because physical activity can alter levels of reproductive hormones, investigators have hypothesized that active individuals should experience decreased incidence of breast or prostate cancer. The better conducted studies suggest that exercise may reduce the risk of developing breast cancer. However, the epidemiological data on prostate cancer have been inconsistent. Meanwhile, data on other site-specific cancers have been sparse. An exciting and emerging body of research has suggested that exercise, at least in moderate amounts, can enhance the human immune system. Theoretically, then, this provides a further biological basis for expecting an inverse relationship between physical activity and cancer risk. However, the changes seen in immune function tend to be transient in nature; thus, the physiological significance with respect to cancer development is uncertain. Preliminary data also suggest that exercise may be beneficial for cancer patients by improving the quality of life and enhancing immune function. Although promising, this needs more careful research. Again, it is unclear whether the enhanced immune function is of any clinical significance in retarding the spread of cancer that has already developed. Finally, with regard to URTIs, moderate exercise appears to decrease the risk of this infection, although high-endurance exercise may increase the risk. This finding parallels the changes seen in the immune system in response to exercise and comes as no surprise, as the immune system also regulates susceptibility to infections.     

Serum enzyme activity and physical condition

Following the WHO tri-axial classification of mental disorders, which set out possibilities for differential classification and diagnosis among the syndromes, the present article suggests complementary axes upon which educational therapy can be based in the psychoses of autism and allied disorders. They are offered as a basis of common ground for discussion in multidisciplinary teams.     

Pragmatic assessment of physical activity

Nurse practitioners are confronted with the need to measure the physical activity levels of clients. There is no "gold standard" for measurement in the field. Nurses increasingly use physical activity for assessment, intervention, and evaluation. Selection of the appropriate tool depends on the purpose of the assessment, the client population, practicality, and psychometric properties of the instrument. Nine physical activity instruments with good psychometric properties, economy, and acceptability are presented to assist with instrument selection.     

Studies on the influence of glucose infusion on parameters of hemostasis

In continuation of previous in vitro experiments the influence of glucose infusions on the following haemostatic functions was investigated: bleeding time, platelet count, platelet aggregation, release reaction, fibrinogen concentration, partial thromboplastin time. Five volunteers with normal metabolism a glucose infusion (100 g) was given for two hrs. Before, 1, 2, 3, 4 and 5 hrs after the beginning of the infusion blood sugar, insulin level and haemostatic parameters were determined. Apart from an increase in the glucose and insulin level, a prolonged bleeding time, increased platelet count, inhibition of platelet aggregation and release reaction occurred. Simultaneously, fibrinogen concentration increased and partial thromboplastin time shortened. The possible causes of these changes in haemostasis during glucose supply are discussed.     

The effect of physical training on lipid parameters in the blood

Physical training leads to an improved metabolic capacity of musculature. At the same time through a decreased liberation of catecholamines a reduction of the increased lipolysis develops. The two factors together condition an improved glucose tolerance and a decrease of the reactive insulin secretion. Thus, among others, the synthesis of triglycerides is reduced and an essential factor of risk is favourably influenced for the development of arteriosclerosis.     

Effects of obesity, social interactions, and physical environment on physical activity in preschoolers.

Examined demographic, environmental, and parent–child interactional correlates of physical activity in 222 preschoolers (aged 3–6 yrs). Results indicate a significant relationship between (1) children's relative weight, parental weight status, and percentage of time spent outdoors, and (2) children's activity levels. Parental obesity was associated with lower levels of physical activity in children. Childhood relative weight was associated with slightly higher levels of physical activity, and more outdoor activity was associated with higher activity levels. Parental participation in children's activities significantly interacted with levels of parental obesity in predicting children's activity levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

回转窑结构和操作参数对球团产量和质量的影响研究

从热工角度,首先简析了回转窑内的热工行为,然后总结了回转窑的三类变量;在此基础上,系统分析了回转窑结构和操作参数对球团产量和质量的影响;最后从优化结构和操作参数角度提出了提高球团产量和质量的途径。     

物性参数对氢冶金流程能耗及碳排放的影响

计算了在把H2和CO混合气体作为还原气的氢冶金过程中还原出1t直接还原铁的需气量、碳排放量及还原气可回收率,分析它们受还原气温度及H2体积分数的影响,同时分析了直接还原铁中铁质量分数对需气量的影响.计算结果表明:在H2和C0混合还原气氛下,当还原气温度为1300℃,H2体积分数为26％时,需气量最小,为826 m3/t...     

Effects of physical activity and diet on lipoprotein(a)

Lipoprotein(a) [Lp(a)] represents a class of lipoproteins with some structural similarity to low density lipoprotein (LDL), but containing a unique apoprotein, apoprotein(a). First reported in 1963, Lp(a) is now considered to have an independent role in the development of atherosclerotic lesions. The level of Lp(a) in the blood is under strong genetic influence and does not appear to be alterable by lifestyle factors known to influence other lipoproteins. Regular moderate exercise has been shown to favorably alter other lipoproteins, and recent attention has focused on whether Lp(a) level can be influenced by physical activity. Current data from cross-sectional and intervention studies show little effect of moderate exercise on serum Lp(a) concentration. One possible exception may be an elevation of serum Lp(a) concentration in adult endurance and power athletes who exercise intensely on a daily basis. However, not all studies have taken into account possible racial or ethnic differences in Lp(a) concentrations and the skewed distribution observed within most populations. Standard dietary intervention such as a low fat diet recommended for weight loss and control of other blood lipids has little effect on serum Lp(a) level. At present, serum Lp(a) concentration does not appear to be significantly altered by realistic dietary changes and moderate physical activity as recommended for health. The synergistic effect on cardiovascular disease risk when both LDL-cholesterol and Lp(a) are elevated highlight the importance of attending to those risk factors that can be modified by exercise and other lifestyle changes.