Assessment of insulin sensitivity during exercise training program in obese women. Comparison of simple indices with hyperinsulinemic euglycemic clamp technique

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.     

Dietary Natural Compounds and Vitamins as Potential Cofactors in Uterine Fibroids Growth and Development

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.     

Immunosenescence increases the rate of acceptance of kidney allotransplants in elderly recipients through exhaustion of CD4 T-cells

Compromised immunity is the hallmark of ageing. Paradoxically, it may be “an ally” in facilitating acceptance of allogeneic grafts in the elderly. In this retrospective study we looked for biomarkers of immunosenescence that distinguish elderly recipients less prone to reject kidney allografts.Recruited kidney recipients aged ≥60 or <60 were designated ‘elderly’ and ‘young’, respectively. Both age-groups were divided according to the history of acute rejection. The phenotype, length of telomeres, expression of FoxP3 and proliferative responses were assessed in CD4⁺ and CD8⁺ T-cell subsets. In addition, IL6, IL10 and TGFβ were measured on the level of mRNA and serum protein.Acute-rejection-free history in elderly transplant recipients was associated with short telomeres, a decreased proportion of CD28⁺ T-cells associated with CMV-seropositivity and low proliferation of CD4⁺ T-cells. In contrast, elderly recipients who experienced acute rejection kept preserved telomere length, had a higher number of functional CD4⁺CD28⁺ cells and exhibited vigorous proliferation in vitro. These differences were not found in the young group.The major conclusion of this study is that the impaired condition of CD4⁺ T-cells, so-called immunosenescence, renders transplant recipients less responsive to an allogeneic kidney graft, an effect that was limited to transplant recipients of >60 years of age.     

Differences in risk factors for breast cancer molecular subtypes in a population-based study.

Analysis of gene expression data suggests that breast cancers are divisible into molecular subtypes which have distinct clinical features. This study evaluates whether pathologic features and etiologic associations differ among molecular subtypes. We evaluated 804 women with invasive breast cancers and 2,502 controls participating in a Polish Breast Cancer Study. Immunohistochemical stains for estrogen receptor alpha, progesterone receptor, human epidermal growth factor receptors (HER2 and HER1), and cytokeratin 5 were used to classify cases into five molecular subtypes: luminal A, luminal B, HER2-expresing, basal-like, and unclassified. Relative risks were estimated using adjusted odds ratios and 95% confidence intervals. We observed that compared with the predominant luminal A tumors (69%), other subtypes were associated with unfavorable clinical features at diagnosis, especially HER2-expressing (8%) and basal-like (12%) tumors. Increasing body mass index significantly reduced the risk of luminal A tumors among premenopausal women (odds ratios, 0.71; 95% confidence intervals, 0.57-0.88 per five-unit increase), whereas it did not reduce risk for basal-like tumors (1.18; 0.86-1.64; P(heterogeneity) = 0.003). On the other hand, reduced risk associated with increasing age at menarche was stronger for basal-like (0.78; 0.68-0.89 per 2-year increase) than luminal A tumors (0.90; 0.95-1.08; P(heterogeneity) = 0.0009). Although family history increased risk for all subtypes (except for unclassified tumors), the magnitude of the relative risk was highest for basal-like tumors. Results from this study have shown that breast cancer risk factors may vary by molecular subtypes identified in expression studies, suggesting etiologic, in addition to clinical, heterogeneity of breast cancer.     

Assessment of selected adhesion molecule and proinflammatory cytokine levels in the vitreous body of patients with type 2 diabetes — role of the inflammatory–immune process in the pathogenesis of proliferative diabetic retinopathy

Background  The aim of the study is to demonstrate the participation of the inflammatory-immune process in the pathogenesis of proliferative diabetic retinopathy (PDR). Methods  Twenty four women and 22 men with type 2 diabetes (mean age 63.97 ± 9.00 years, mean duration of diabetes 12.56 ± 6.87 years) were enrolled in the study. Serum concentrations of soluble forms of ICAM-1, VCAM-1 as well as IL-6 and TNF-α were evaluated in all study subjects. In 19 patients, simultaneous assessment of selected parameter levels in both serum and vitreous samples was performed. Vitrectomy was performed due to intravitreal hemorrhage, accompanied in some patients by traction retinal detachment. The control group consisted of 15 patients having undergone vitrectomy for reasons other than PDR. Tests were performed using the ELISA method. Results  Serum and intraocular concentrations of sICAM-1, sVCAM-1, IL-6, TNF-α were considerably higher in study subjects with PDR than in controls. Simultaneously, a positive correlation was found between intraocular sVCAM-1 (r = 0.590, p = 0.007), TNF-α (r = 0.822, p < 0.001) concentrations and HbA₁c levels. The above-mentioned dependence was not shown for sICAM-1 and IL-6 vitreous concentration. Local vitreous VCAM-1 level increase was also dependent on vitreous TNF-α concentration growth (r = 0.470, p = 0.043). No significant correlation was found between serum and vitreous levels of the selected parameters in the group of 19 patients with PDR. Conclusions  Increase in sICAM-1 and sVCAM-1 levels, as well as their correlation with high vitreous IL-6 and TNF-α concentrations in patients with PDR, seem to confirm the inflammatory–immune nature of this process. In diabetes, inadequate metabolic control remains an important risk factor in the development of PDR. We disclose commercial or similar relationships to products or companies mentioned in or related to the subject matter of the article being submitted. We have full control of all primary data and we agree to allow Graefe’s Archive for Clinical and Experimental Ophthalmology to review our data if requested.     

Sterility and antibacterial activity of some antibiotics sterilized by irradiation

Sterility and antibacterial activity of several antibiotics (including some penicillins and their salts, gramicidin and neomycin) subjected to sterilization by irradiation has been studied. The compounds in solid phase have been exposed to gamma irradiation in air atmosphere at room temperature, with a dose of 25 kGy, and afterwards they have been subjected to tests recommended by FP V (volume I, 1990) checking their sterility and activity. The results have shown that the majority of initial compounds have been to a slight degree contaminated by bacteria from the genera Bacillus and Micrococcus, the number of bacteria did not exceed 10(2) CFU, and fungi up to 10 CFU in 1 g of the compound. All compounds subjected to sterilization with a dose of 25 kGy were sterile and preserved the activity required by FP V. The decrease in activity observed for some compounds was always within the limits of FP specification. The results have proved that the penicillins analysed, gramicidin and neomycin can be sterilized by irradiation with a dose of 25 kGy, without any detrimental effect on their properties and antibacterial activity.