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61.
The aim of our study was to evaluate the effect of BMI on the change in circulating sex hormone in postmenopausal women during 6 months of oral continuous combined low-dose hormone therapy (HT). Fifty postmenopausal women were allocated to receive daily one tablet containing combination of 17β-estradiol (1 mg)/norethindrone acetate (0.5 mg) for 6 months. Serum levels of follicle-stimulating hormone (FSH), estradiol, total testosterone, sex hormone-binding globulin (SHBG), free androgen index (FAI), free estrogen index (FEI), Δ4-androstendione (Δ4A), and dehydroepiandrosterone sulfate were assessed at baseline and at the end of 6 months. Mean absolute values and percent changes from baseline were compared between lean and overweight women. Mean FSH decreased and mean 17β-estradiol increased significantly in both groups (FSH lean: 82.3 ± 26.7 decreased to 45.0 ± 17.0 mIU/ml, P = 0.0001; FSH overweight: 85.5 ± 22.1 decreased to 52.3 ± 23.8 mIU/ml, P = 0.003; P between groups = 0.661; E2 lean: 23.24 ± 12.55 increased to 53.62 ± 28.29 pg/ml, P = 0.006; E2 overweight: 24.17 ± 10.88 increased to 68.36 ± 53.99 pg/ml, P = 0.0001; P between groups = 0.619). Lean individuals had statistically significant higher increments of FAI and specifically FEI compared to overweight (FEI lean; 0.14 ± 0.09 increased to 0.29 ± 0.14, P = 0.009; overweight 0.23 ± 0.18 increased to 0.52 ± 0.40, P = 0.126; P between groups = 0.034). Although BMI does not affect total 17β-estradiol changes, free sex steroid concentrations increase more steeply in lean compared to overweight women receiving oral low-dose HT.  相似文献   
62.
Oxidized low-density lipoprotein (ox-LDL) incorporation into intimally resident vascular cells via scavenger receptors marks one of the early steps in atherosclerosis. Cellular apoptotic damage results from two major serial intracellular events: the binding and scavenger receptor-mediated uptake of oxidizable lipoproteins and the intracellular oxidative responses of accumulated lipoproteins. Most molecular approaches to prevent apoptotic damage have focused on singular events within the cascade of lipoprotein trafficking. To identify a multifocal strategy against LDL-induced apoptosis, we evaluated the role of cellular preconditioning by glutathione-ethyl ester (GSH-Et), a native redox regulator, in the prevention of the uptake and apoptotic effects of an oxidizable scavenger receptor-specific ligand, acetylated low-density lipoprotein (Ac-LDL). Our results indicate that GSH-Et-mediated protein kinase C (PKC) pathway modulation regulates Ac-LDL binding and incorporation into GSH-Et preconditioned cells and subsequently delays reactive oxygen intermediate generation and apoptotic conversion. The GSH-Et protective effects on apoptosis and Ac-LDL binding were reversed by calphostin C, a PKC inhibitor, and were accompanied by an increase in PKC phosphorylation. However, the rate of reactive oxygen intermediate accumulation was not increased following calphostin C treatment, suggesting that GSH-Et may play an important nonreactive oxygen-intermediate-based protective role in regulating apoptotic dynamics. Overall, we report on the novel role for GSH-Et preconditioning as a molecular strategy to limit lipoprotein entry into the cells, which presents a proactive modality to prevent cellular apoptosis in contrast with the prevalent antioxidant approaches that treat damage retroactively.  相似文献   
63.
Objective: The purpose of this study was to examine energy intake, energy expenditure, diet composition, and obesity of adolescents in Northern Greece. Research Methods and Procedures: Anthropometric measurements were taken for all participants. Height, weight, and skinfold thickness at two sites were measured. BMI and percentage body fat were calculated. Energy intake and macronutrient and micronutrient intakes were determined by a 3‐day weighed dietary diary. Energy expenditure was calculated based on calculated resting metabolic rate (RMR) 1 multiplied by an activity factor based on reported physical activity. Results: Thirty‐one percent of boys and 21% of girls had BMI corresponding to ≥25 kg/m2 at 18 years and were classified as overweight. Both overweight boys and girls reported a lower energy intake compared with their non‐overweight counterparts when expressed as kilocalories per kilogram body weight. Overweight children had a higher negative energy balance. Both overweight and non‐overweight adolescents had higher than recommended fat intakes. Mean daily carbohydrate, protein, and fat intake, expressed as grams per kilogram body weight, of overweight adolescents were significantly lower compared with the non‐overweight adolescents. Total daily carbohydrate intake, when expressed in grams, was found to be higher for non‐overweight adolescents. Both overweight boys and girls had lower iron intakes than their non‐overweight counterparts. Overweight boys had statistically lower fiber and niacin intakes than non‐overweight boys. Both overweight and non‐overweight adolescents had lower than recommended iron intakes. Furthermore, overweight adolescents consumed more snacks (potato chips, chocolate bars, pizza, cheese pie, and cream pie), more sugar, jam, and honey, and fewer legumes, vegetables, and fruits than their non‐overweight counterparts. Discussion: Reported energy intake of overweight adolescents was lower than their non‐overweight counterparts. Regarding diet composition overweight subjects had significantly lower intakes of carbohydrates compared with non‐overweight subjects. The food consumption pattern of overweight children showed less adherence to the traditional Mediterranean diet.  相似文献   
64.
Episomal expression of Leishmania histone H1 sense mRNAs in Leishmania major promastigotes was found previously to result in overexpression of this molecule and to reduce parasite infectivity in vitro. Herein, we evaluated the in vivo infectivity of these transfectants, in BALB/c mice, and showed that it is dramatically reduced. No lesions were observed in this group of mice and this was associated with an extremely low number of parasites both in the footpad and in the draining lymph nodes. Interestingly, the transfectants-reduced infectivity was associated with a delay in their cell-cycle progression and differentiation to axenic amastigotes, assessed in vitro. Therefore, the dramatic reduction in their infectivity may be attributed to the above-mentioned phenotypic modifications. As the metazoan linker histone H1(0) homologue is known to delay cell-cycle progression in mammalian cells we investigated whether its Leishmania counterpart, which possesses homology to its C-terminal region, when expressed in mammalian cells may also affect their cell-cycle progression. It was thus shown that Leishmania histone H1 expressed in COS7 and NIH 3T3 cells, delays cell-cycle progression in these cells too. The latter strengthens the phenotype observed in Leishmania and provides evidence that critical functions of histone H1 molecules are conserved throughout evolution.  相似文献   
65.
The small heat shock protein Hsp20 protects cardiomyocytes against apoptosis, and phosphorylation at its Ser16 site enhances its cardioprotection. To determine whether genetic variants exist in human Hsp20, which may modify these beneficial effects, we sequenced the coding region of the Hsp20 gene in 1347 patients suffering from dilated cardiomyopathy and 744 subjects with no heart disease. We identified a C59T substitution in the human Hsp20 gene in one patient and three individuals without heart disease. All subjects were heterozygous for this mutation, which changes a fully conserved proline residue into leucine at position 20 (P20L), resulting in secondary structural alterations. To examine the potential functional significance of the P20L-Hsp20 human variant, adult rat cardiomyocytes were infected with Ad.GFP (where Ad is adenovirus and GFP is green fluorescent protein), Ad.WT-Hsp20 (where WT is wild-type), and Ad.P20L-Hsp20 and subjected to simulated ischemia/reperfusion injury. Expression of WT-Hsp20 resulted in significant attenuation of apoptosis compared with the GFP control. However, the P20L-Hsp20 mutant showed no protection against apoptosis, assessed by Hoechst staining and DNA fragmentation. The loss of cardioprotection by the mutant Hsp20 was associated with its diminished phosphorylation at Ser16 compared with WT-Hsp20. Furthermore, maximal stimulation of cardiomyocytes with isoproterenol or protein kinase A-mediated phosphorylation in vitro confirmed the impaired ability of the mutant Hsp20 to become phosphorylated at Ser16. In conclusion, we have identified a P20L substitution in human Hsp20, which is associated with diminished phosphorylation at Ser16 and complete abrogation of the Hsp20 cardioprotective effects which may adversely affect the ability of human carriers to cope with cellular stress.  相似文献   
66.
The effects ofphosphorylation status on Ca2+release and Ca2+ removal werestudied in fast-twitch flexor digitorum brevis and slow-twitch soleusskeletal muscle fibers enzymatically isolated from wild-type andphospholamban knockout (PLBko) mice. In all fibers the adenosine3',5'-cyclic monophosphate-dependent protein kinase (PKA)inhibitor H-89 decreased the peak amplitude of the intracellularCa2+ concentration([Ca2+]) transient fora single action potential, and the PKA activator dibutyryl adenosine3',5'-cyclic monophosphate (DBcAMP) reversed this effect,indicating modulation of Ca2+release by phosphorylation status in all fibers. H-89 decreased thedecay rate constant of the[Ca2+] transient andDBcAMP reversed this effect only in phospholamban-expressing fibers(wild-type soleus), indicating modulation ofCa2+ removal only in the presenceof phospholamban. A high basal level of PKA phosphorylation in soleusfibers maintained under our control conditions was indicated bythe lack of effect of direct application of DBcAMP onCa2+ release orCa2+ removal in wild-type or PLBkosoleus fibers and was confirmed by analysis of phospholamban fromwild-type soleus fibers.

  相似文献   
67.
Endometriosis is an inflammatory disease of women of reproductive age featured by the presence of ectopic endometrium and is strongly related to infertility. Galectins, carbonhydrate-binding proteins, have been found to have pro- or anti-inflammatory roles in the reproductive tract and in pathological conditions concerning infertility. Galectin-1, which is expressed at endometrium and decidua, plays a major role in implantation and trophoblast invasion. Also, the neuropeptides, corticotropin releasing hormone (CRH) and urocortin (UCN) and their receptors are expressed in eutopic and ectopic endometrium showing a differential expression pattern in endometriotic women compared to healthy ones. The aim of this study was to examine the galectin-1 expression in endometriotic lesions and compare its expression in eutopic endometrium of endometriotic and healthy women. Furthermore, we examined the effect of CRH and UCN in galectin-1 expression in Ishikawa cell line and macrophages and investigated the implication of CRHR1 in these responses. Eutopic and ectopic endometrium specimens, Ishikawa cell line and mice macrophages were used. Immunohistochemistry and western blot analysis were performed in order to identify galectin-1 expression in ectopic and eutopic endometrium of women with and without endometriosis and the regulatory effect of CRH and UCN on galectin-1 expression. This study presents for the first time that galectin-1 is overexpressed in endometriotic lesions compared to eutopic endometrium of endometriotic women and is more abundantly expressed in eutopic endometrium of disease women compared to healthy ones. Furthermore, it is shown that CRH and UCN upregulate galectin-1 expression in Ishikawa cell line and macrophages and this effect is mediated through CRHR1. These results suggest that galectin-1 might play an important role in endometriosis pathology and infertility profile of women suffering from endometriosis by being at the same time regulated by CRH and UCN interfering in the immune disequilibrium which characterizes this pathological condition.  相似文献   
68.
Protein microbicides containing neutralizing antibodies and antiviral lectins may help to reduce the rate of infection with human immunodeficiency virus (HIV) if it is possible to manufacture the components in large quantities at a cost affordable in HIV‐endemic regions such as sub‐Saharan Africa. We expressed the antiviral lectin griffithsin (GRFT), which shows potent neutralizing activity against HIV, in the endosperm of transgenic rice plants (Oryza sativa), to determine whether rice can be used to produce inexpensive GRFT as a microbicide ingredient. The yield of OSGRFT in the best‐performing plants was 223 μg/g dry seed weight. We also established a one‐step purification protocol, achieving a recovery of 74% and a purity of 80%, which potentially could be developed into a larger‐scale process to facilitate inexpensive downstream processing. OSGRFT bound to HIV glycans with similar efficiency to GRFT produced in Escherichia coli. Whole‐cell assays using purified OSGRFT and infectivity assays using crude extracts of transgenic rice endosperm confirmed that both crude and pure OSGRFT showed potent activity against HIV and the crude extracts were not toxic towards human cell lines, suggesting they could be administered as a microbicide with only minimal processing. A freedom‐to‐operate analysis confirmed that GRFT produced in rice is suitable for commercial development, and an economic evaluation suggested that 1.8 kg/ha of pure GRFT could be produced from rice seeds. Our data therefore indicate that rice could be developed as an inexpensive production platform for GRFT as a microbicide component.  相似文献   
69.
We present a compelling case of simultaneous, bilateral tibial stress fractures occurring in a unique epiphyseal and posterior location, with unclear aetiology. An overweight, Caucasian male in his late 20s developed synchronous bilateral medial knee pain following an intense 10-day training regimen. His radiographies were normal, but MRI revealed almost identical bilateral stress fracture lines in the posteromedial tibial epiphyses. Bone mineral densitometry and a full metabolic and hormonal panel were performed to further investigate potential underlying metabolic bone disease. He was found to have normal bone mineral densitometry and low Vitamin D serum values. Symptomatology greatly improved with activity modification. There were no further complaints and complications at 12 months’ follow-up. Diagnosis can be challenging and the treating physician should be acquainted with the basic science of stress fractures and main discriminating clinical, biochemical and radiological characteristics from insufficiency fractures, to avoid pitfalls in treatment decision.  相似文献   
70.
Abstract: We have reported the production of monoclonal antibody 4C5, which recognizes a cell surface antigen, the 4C5 antigen, involved in granule cell migration processes. In the present study, we investigated in a more precise manner the role of the 4C5 antigen in the different types of granule cell migrations that take place during cerebellar development. When cerebellar explant cultures derived from 10-day-old rats were performed for 2 days in the presence of monoclonal antibody 4C5, vertical granule cell migration, occurring in the presence of glia, was not significantly inhibited. In contrast, when monoclonal antibody 4C5 was included in the medium of microexplant cultures derived from 4-day-old mice and maintained for 4 days in vitro, granule cell migrations that occurred both parallel and perpendicular to the neurite bundles that were free of glia were inhibited. Moreover, a stronger inhibitory effect of the antibody was observed on migration perpendicular to the neurite bundles compared with the parallel type of migration. Our results indicate that the 4C5 antigen differentially affects the different developmental stages and types of granule cell migration during rodent cerebellar development.  相似文献   
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