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Insulin resistance is a key element of metabolic syndrome, which includes disturbances of glucose tolerance, obesity, hypertension, coronary heart disease dyslipidemia and many other defects. An important problem in scientific research is precise measurement of insulin sensitivity. The method considered "the gold standard" is glucose clamp, however, it is difficult to apply this method in large studies. Therefore, simple indices of insulin resistance are proposed. It remains unclear whether those indices are able to reflect changes occurring during insulin-sensitizing intervention. The aim of the present study was to assess the use of indirect indices for the changes in insulin sensitivity during exercise training and to compare those indices with results derived from clamp. Fourteen obese normoglycemic women participated in 12-week exercise training program, which included exercise performed on a bicycle ergometer, 5 days a week for 30 minutes. Insulin sensitivity (M/FFM value) before and after training was measured with hyperinsulinemic euglycemic clamp technique. Simple indices of insulin resistance were also assessed: fasting plasma insulin (INS), logarithm INS (log [INS]), homeostasis model assessment (HOMA), logarithm HOMA (log [HOMA]) and quantitative insulin sensitivity check index (QUICKI). Before training, all those indices were markedly related to M/FFM. After training, an increase in M/FFM was observed. None of the examined indices markedly changed after training. There was no correlations between changes of evaluated indices and in M/FFM during training, and no relationships of those parameters after training. Our study indicates that simple indices are not able to reflect changes occurring during insulin-sensitizing intervention.  相似文献   
75.
An analysis of the literature generated within the past 20 year-span concerning risks of uterine fibroids (UFs) occurrence and dietary factors was carried out. A link between Vitamin D deficiency and UFs formation is strongly indicated, making it a potent compound in leiomyoma therapy. Analogs of the 25-hydroxyvitamin D3, not susceptible to degradation by tissue 24-hydroxylase, appear to be especially promising and tend to show better therapeutic results. Although research on the role of Vitamin A in the formation of fibroids is contradictory, Vitamin A-enriched diet, as well as synthetic retinoid analogues, may be preventative or limit the growth of fibroids. Unambiguous conclusions cannot be drawn regarding Vitamin E and C supplementation, except for alpha-tocopherol. Alpha-tocopherol as a phytoestrogen taking part in the modulation of estrogen receptors (ERs) involved in UF etiology, should be particularly avoided in therapy. A diet enriched in fruits and vegetables, as sources of carotenoids, polyphenols, quercetin, and indole-3-carbinol, constitutes an easily modifiable lifestyle element with beneficial results in patients with UFs. Other natural substances, such as curcumin, can reduce the oxidative stress and protect against inflammation in leiomyoma. Although the exact effect of probiotics on uterine fibroids has not yet been thoroughly evaluated at this point, the protective role of dairy products, i.e., yogurt consumption, has been indicated. Trace elements such as selenium can also contribute to antioxidative and anti-inflammatory properties of a recommended diet. In contrast, heavy metals, endocrine disrupting chemicals, cigarette smoking, and a diet low in antioxidants and fiber were, alongside genetic predispositions, associated with UFs formation.  相似文献   
76.
Two series of N-[(4-arylpiperazin-1-yl)-alkyl]-2-azaspiro[4.4]nonane (5-10) and [4.5]decane-1,3-dione (11-16) derivatives were synthesized and their serotonin 5-HT1A and 5-HT2A receptor affinities were determined. Compounds with the methylene spacer (5-7 and 11-13) exhibited low 5-HT1A/5-HT2A receptor affinity, in contrast to their ethylene analogues regarded as potent 5-HT1A ligands, especially those containing a cyclohexane moiety (14-16; Ki = 5.1, 2.7 and 4.3 nM, respectively) in the 3-position of the pyrrolidine-2,5-dione ring. Moreover, derivatives with 3-chloro substituent (10 and 14) showed distinct affinity for 5-HT2A receptors. The functional activity of compounds 10, 14, 15 and 16 was tested in vivo in the commonly used animal models. In those experiments, the tested compounds showed features of agonists of pre- and postsynaptic (14), agonists of presynaptic and antagonists of postsynaptic (10, 15), or agonists of postsynaptic (16) 5-HT1A receptors. Additionally, 10 and 16 exhibited properties of potential 5-HT2A receptor antagonists. The above results suggested a crucial role of the spacer between the amide fragment and 4-arylpiperazine moiety, as well as of the size of the cycloalkyl ring at the 3-position of pyrrolidine-2,5-dione ring in functional 5-HT1A/5-HT2A properties.  相似文献   
77.
There has been a call for research on migrant and refugee women’s negotiation of diverse discourses and cultural constraints associated with sexual embodiment, including menopause, in order to facilitate sexual and reproductive health and understand gendered subjectivity. This study examined the construction and experience of menopause among migrant and refugee women who had settled in Australia or Canada in the last 10 years. Eighty-four individual interviews and 16 focus groups comprising 85 participants were conducted (total n?=?169), with women aged 18 years and over from Afghanistan, India (Punjab), Iraq, Somalia, South Sudan, Sri-Lanka (Tamil), Sudan and various South American (Latina) backgrounds. Thematic decomposition identified three discursive themes: Menopause as the Age of Despair; a Discourse of Silence and Secrecy; and Menopause as a Life Stage – or when Life Starts. Negative constructions of menopause, associated with silence and secrecy, were evident across different cultural groups, with implications for women’s positioning and experience of menopausal change and embodiment. However, resistance to negative discourse was also evident. This was primarily associated with having received menopause education and more open communication about menopausal change, suggesting that education and health information can facilitate affirming aspects of menopause.  相似文献   
78.

Introduction

Asymmetric dimethylarginine (ADMA) is an endogenous competitive inhibitor of endothelial nitric oxide synthase. Asymmetric dimethylarginine may influence the process of restenosis after coronary angioplasty. The aim of the study was to determine if initial plasma ADMA level could predict restenosis after coronary angioplasty and stenting.

Material and methods

The study group consisted of 60 consecutive patients (10 women and 50 men, average age 58.9 ±10.4 years old), who underwent percutaneous coronary angioplasty with bare metal stenting for stable coronary artery disease. All patients underwent follow-up coronary angiography after a 6-month period. Patients were divided into two groups, one with restenosis (n = 22), and the other one without restenosis (n = 38). In addition to measuring acknowledged restenosis risk factors, plasma ADMA level was measured before initial angiography.

Results

Asymmetric dimethylarginine plasma level was significantly higher in the group with restenosis than in the group without restenosis (1.94 ±0.94 µmol/l vs. 0.96 ±0.67 µmol/l; p < 0.05). L-arginine/ADMA ratio was also decreased in the group with restenosis, when compared with the group without restenosis (p < 0.05). Multivariate logistic regression revealed that independent restenosis risk factors were characterised by an initially high ADMA level (p < 0.01), advanced age (p < 0.05) and low level of HDL cholesterol (p < 0.05).

Conclusions

Pre-procedural elevated plasma ADMA level increases the risk of restenosis in patients who underwent coronary angioplasty and stenting with bare metal stents.  相似文献   
79.
This article summarizes the results of studies concerning the influence of the ventral tegmental area (VTA) on the hippocampal theta rhythm. Temporary VTA inactivation resulted in transient loss of the hippocampal theta. Permanent destruction of the VTA caused a long‐lasting depression of the power of the theta and it also had some influence on the frequency of the rhythm. Activation of glutamate (GLU) receptors or decrease of GABAergic tonus in the VTA led to enhancement of dopamine release and increased hippocampal theta power. High time and frequency cross‐correlation was detected for the theta band between the VTA and hippocampus during paradoxical sleep and active waking. Thus, the VTA may belong to the broad network involved in theta rhythm regulation. This article also presents a model of brainstem–VTA–hippocampal interactions in the induction of the hippocampal theta rhythm. The projections from the VTA which enhance theta rhythm are incorporated into the main theta generation pathway, in which the septum acts as the central node. The neuronal activity that may be responsible for the ability of the VTA to regulate theta probably derives from the structures associated with rapid eye movement (sleep) (REM) sleep or with sensorimotor activity (i.e., mainly from the pedunculopontine and laterodorsal tegmental nuclei and also from the raphe). Synapse 69:553–575, 2015 . © 2015 Wiley Periodicals, Inc.  相似文献   
80.
The effects of various protease inhibitors on the development of antinociceptive tolerance to morphine were examined in mice. Intrathecal (i.t.) administration of morphine (0.01-1 nmol) produced a dose-dependent and significant antinociceptive effect in the 0.5% formalin test. When the doses of morphine (mg/kg, s.c. per injection) were given as pretreatment twice daily for two days [first day (30) and second day (60)], i.t. administration of morphine (0.1 nmol) was inactive due to antinociceptive tolerance on the third day. Tolerance to i.t. morphine was significantly suppressed by the i.t. injection of N-ethylmaleimide or Boc-Tyr-Gly-NHO-Bz, inhibitors of cysteine proteases involved in dynorphin degradation, as well as by dynorphin A, dynorphin B and (-) U-50,488, a selective kappa-opioid receptor agonist. On the other hand, amastatin, an aminopeptidase inhibitor, phosphoramidon, an endopeptidase 24.11 inhibitor, lisinopril, an angiotensin-converting enzyme inhibitor, and phenylmethanesulfonyl fluoride, a serine protease inhibitor, were inactive. These results suggest that cysteine protease inhibitors suppress the development of morphine tolerance presumably through the inhibition of dynorphin degradation.  相似文献   
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