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Background

Cardiovascular diseases have been associated with depression in later life, and a potential mechanism is inhibition of angiogenesis. We designed this study to determine if depression is associated with higher serum concentration of endostatin, an endogenous angiogenesis inhibitor.

Methods

We performed a cross-sectional examination of a random sample of men aged 69–86 years. Those who scored 7 or higher on the 15-item Geriatric Depression Scale were deemed depressed. We determined the concentration of serum endostatin using a reproducible assay. Other measures included age, education, body mass index, smoking, history of depression, use of antidepressants, hypertension, diabetes, coronary heart disease and stroke, high sensitivity C-reactive protein, plasma homocysteine, triglycerides and cholesterol. We used logistic regression to investigate the association between endostatin and depression, and adjusted the analyses for confounding factors.

Results

Our sample included 1109 men. Sixty-three (5.7%) men were depressed. Their serum endostatin was higher than that of nondepressed participants (p = 0.021). Men in the highest decile of endostatin had greater adjusted odds of depression (odds ratio [OR] 1.78, 95% confidence interval [CI] 1.03–3.06). A doubling of endostatin doubled the odds of depression (OR 1.93, 95% CI 1.31–2.84). The probability of depression increased with the concentration of endostatin in a log-linear fashion up to a maximum of about 20%–25%.

Limitations

The cross-sectional design limits the study’s ability to ascribe causality to the association between high endostatin and depression.

Conclusion

Serum endostatin is associated with depression in older men. It remains to be established whether correction of this imbalance is feasible and could decrease the prevalence of depression in later life.  相似文献   
23.
Immunotherapy has raised the attention of many scientists because it hold promise to be an attractive therapeutic strategy to treat a number of disorders. In this study, the immunomodulatory effects of low titers of Newcastle disease virus (NDV) AF2240 on human peripheral blood mononuclear cells (PBMC) were analyzed. We evaluated cytokine secretion and PBMC activation by cell proliferation assay, immunophenotyping and enzyme linked immunosorbent assay. The proliferation of the human PBMC was measured to be 28.5% and 36.5% upon treatment with 8 hemaglutinin unit (HAU) and 2 HAU of NDV respectively. Interestingly, the percentage of cells with activating markers CD16 and CD56 were increased significantly. Furthermore, the intracellular perforin and granzyme levels were also increased upon virus infection. Human PBMC treated with NDV titer 8 HAU was found to stimulate the highest level of cytokine production including interferon-γ, interleukin-2 and interleukin-12. The release of these proteins contributes to the antitumor effect of PBMC against MCF-7 breast cancer cells. Based on the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay, activated human PBMC showed high cytolytic efficiency towards human breast tumor cells. In summary, NDV was able to stimulate PBMC proliferation, cytokine secretion and cytolytic activity.  相似文献   
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Increasing age is a predictor of ill-health and mortality related to cardiovascular disease and to frailty, a syndrome characterized by deterioration of multiple organ systems leading to loss of physiological reserve, diminished capacity to cope with stressors, and increased risk of disability and death. As men grow older, their levels of testosterone decline while the prevalence of ill-health increases. Observational studies have linked lower testosterone levels with cardiovascular disease and mortality in middle-aged and older men. More recently, lower testosterone has been shown to predict reduced sexual activity and frailty in aging men. Additional studies are needed to determine whether lower testosterone is a biomarker or a potentially treatable risk factor for poorer health outcomes in older men. During aging, the response of the pituitary–thyroid axis alters to manifest higher thyrotropin levels. The presences of subclinical hypo- and hyper-thyroidism predict adverse cardiovascular outcomes. Newer results indicate that in euthyroid older men, differences in free thyroxine levels within the normal range predict specific health outcomes including frailty. Clarification of the roles of endogenous testosterone and thyroxine in the genesis of ill-health during male aging offers the prospect of future intervention to preserve health and well-being in this growing population.  相似文献   
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Demographic changes resulting in ageing of the world's population have major implications for health. As men grow older, circulating levels of the principal androgen or male sex hormone testosterone (T) decline, while the prevalence of ill-health increases. Observational studies in middle-aged and older men have shown associations between lower levels of T and poorer mental health in older men, including worse cognitive performance, dementia and presence of depressive symptoms. The role of T metabolites, the more potent androgen dihydrotestosterone (DHT) and the oestrogen receptor ligand estradiol (E2) in the pathophysiology of cognitive decline are unclear. Studies of men undergoing androgen deprivation therapy in the setting of prostate cancer have shown subtle detrimental effects of reduced T levels on cognitive performance. Randomised trials of T supplementation in older men have been limited in size and produced variable results, with some studies showing improvement in specific tests of cognitive function. Interventional data from trials of T therapy in men with dementia are limited. Lower levels of T have also been associated with depressive symptoms in older men. Some studies have reported an effect of T therapy to improve mood and depressive symptoms in men with low or low-normal T levels. T supplementation should be considered in men with a diagnosis of androgen deficiency. Beyond this clinical indication, further research is needed to establish the benefits of T supplementation in older men at risk of deteriorating cognition and mental health.  相似文献   
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Fifty seven children with thoracic empyema (37 boys and 20 girls) aged less than 12 years were seen at the University of Port Harcourt Teaching Hospital between January 1989 and December 1991. Staphylococcus aureus was the most common organism isolated from the pus of these patients (36 (63%) patients). Pseudomonas aeruginosa, the next most common organism, was isolated in 10 (18%) patients. The most common symptoms at presentation were acute illness with fever and cough (51 (89%) patients). All the patients were treated with closed intercostal tube drainage and appropriate antibiotics. Decortication was resorted to in only one patient. There were two deaths and the overall survival rate was 97%.  相似文献   
30.
The resurging interest in diagnostic laparoscopy has witnessed its increasing application in trauma surgery. Such unbridled enthusiasm has at times overlooked its shortcoming in the diagnosis and management of certain in abdominal injuries. We report and discuss one such conspicuous limitation and advocate that the use laparoscopy in abdominal trauma should be tempered with caution.  相似文献   
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