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排序方式: 共有1299条查询结果,搜索用时 31 毫秒
131.
132.
Nezis IP Stravopodis DJ Margaritis LH Papassideri IS 《Journal of insect physiology》2006,52(3):282-290
Programmed cell death, constitutes a common fundamental incident that occurs during oogenesis in a variety of different animals. It plays a significant role in the maturation process of the female gamete and also in the removal of abnormal and superfluous cells at certain checkpoints of development. In the present study, we demonstrate the existence of follicular atresia during mid-oogenesis in the olive fruit fly Dacus oleae (Tephritidae). The number of atretic follicles increases following the age of the fly, suggesting for the presence of an age-susceptible process. The atretic follicles contain nurse cells that exhibit chromatin condensation, DNA fragmentation and actin cytoskeleton alterations, as revealed by propidium iodide staining, TUNEL labeling and phalloidin-FITC staining. Conventional light and electron microscopy disclose that the nurse cell remnants are phagocytosed by the adjacent follicle cells. The follicular epithelium also eliminates the oocyte through phagocytosis, resulting to an egg chamber with no compartmentalized organization. The data presented herein are very similar compared to previous reported results in other Diptera species, strongly suggesting the occurrence of a phylogenetically conserved mechanism of follicular atresia. All these observations also support the notion that mid-oogenesis in D. oleae may be the critical regulation point at which superfluous and defective egg chambers are selectively eliminated before they reach maturity. 相似文献
133.
Kolettas E Thomas C Leneti E Skoufos I Mbatsi C Sisoula C Manos G Evangelou A 《Molecular and cellular biochemistry》2006,285(1-2):111-120
Rosmarinic acid (RosA), frequently found as a secondary metabolite in herbs and medicinal plants, has exhibited antioxidative and anti-inflammatory activities. RosA was shown to inhibit the proliferation and induce apoptosis of Jurkat T cells but the mechanism of action of RosA in apoptosis remains elusive. RosA inhibited the proliferation of Jurkat cells in a dose-dependent manner by suppressing the expression of cyclin D3 and p21Cip1/Waf1 and up-regulating p27Kip1. RosA induced apoptosis of Jurkat cells in a dose-dependent manner and failed to protect them from hydrogen peroxide (H2O2)-mediated apoptosis. Induction of apoptosis by RosA correlated with suppression of Bcl-2 but not of Bak or PUMA. Overexpression of Bcl-2 protected Jurkat cells from both H2O2- and RosA-induced apoptosis by altering the ratio of anti- to pro-apoptotic members of the Bcl-2 family. In conclusion, RosA inhibited Jurkat cell proliferation by altering the expression of cyclins and cyclin-dependent kinase inhibitors and induced apoptosis most likely acting through the mitochondrial pathway and possessed no anti-oxidant properties. 相似文献
134.
Kolettas E Skoufos I Kontargiris E Markopoulou S Tzavaras T Gonos ES 《Archives of biochemistry and biophysics》2006,445(1):184-195
The role of clusterin/apolipoprotein J (Clu/ApoJ) and Bcl-2 on C(2)-ceramide-induced apoptosis of embryonic human diploid fibroblasts, MRC-5 and immortalized adult skin keratinocytes, HaCaT was investigated. C(2)-ceramide-induced apoptosis of HaCaT in a time- and dose-dependent manner, while in MRC-5 only at higher concentrations. There was a dose-dependent accumulation of Clu/ApoJ and downregulation of Bcl-2 which correlated with C(2)-ceramide-induced apoptosis of MRC-5. While overexpression of Bcl-2 suppressed C(2)-ceramide-mediated apoptosis in both cell types, Clu/ApoJ failed to do so, accessed by morphological changes, DNA fragmentation and PARP cleavage. There was no change in the expression of endogenous p53 or p21(Waf1/Cip1) upon C(2)-ceramide treatment of MRC-5. However, mutant p53(143ala) increased the sensitivity of MRC-5 to C(2)-ceramide-induced apoptosis by markedly downregulating Bcl-2, pointing to a role for p53. These results suggested that whereas downregulation of Bcl-2 may be a crucial factor involved in C(2)-ceramide-induced apoptosis, accumulation of Clu/ApoJ may be a signal of stress response. Moreover, the ceramide-activated apoptotic pathway may be regulated by p53. 相似文献
135.
136.
Maria Kompoti Anargiros Mariolis Alevizos Alevizos Ioannis Kyriazis Ioannis Protopsaltis Eleni Dimou Ioannis Lentzas Dimitrios Levisianou Afroditi Gova Andreas Melidonis 《Cardiovascular diabetology》2006,5(1):1-5
Objectives
South-Asians have lower adiponectin levels compared to Caucasians. It was not clear however, if this intrinsic feature is related to aspects of glucose metabolism. This study aims to determine the relationship between body fat distribution and adipocytokine in South-Asian subjects by measuring serum adipocytokines, adiposity, insulinemia, and glucose tolerance levels.Methods
In this cross-sectional study, 150 South-Asians (80 males, 70 females) were included, 60 had NGT (Control group, Age 51.33 ± 11.5, BMI 27 ± 2.3), 60 had IGT (Age 57.7 ± 12.5, BMI 27.2 ± 2.7), 30 had type 2 DM (Age 49.5 ± 10.9, BMI 28 ± 1.7). Measures of adiposity, adipocytokines and other metabolic parameters were determined. Parameters were measured using the following: a) Plasma glucose by glucose oxidase method b) CRP by immunoturbidimetric method (Roche/Hitachi analyser) c) insulin by Medgenix INS-ELISA immunoenzymetric assay by Biosource (Belgium) d) Leptin, Adiponectin by radioimmunoassay kits by Linco Research (St. Charles MO) e) Resistin by immunoassay kits by Phoenix Pharmaceuticals INC (530 Harbor Boulevard, Belmont CA 94002, USA).Results
Adiponectin concentrations were highest in NGT, decreased in IGT and lowest in DMT2, (both p < 0.01). Leptin was significantly higher in DMT2 than IGT and NGT p = 0.02 and 0.04 respectively. There was a significant positive relationships between log adiponectin and 2-hr insulin values, p = 0.028 and history of hypertensions and a ischemic heart disease p = 0.008 with R = 0.65. There was a significant inverse correlation between log adiponectin and resistin, p < 0.01.Conclusion
Resistin levels had an inverse correlation with adiponectin levels, indicating an inverse relationship between pro-inflammatory cytokines and adiponectin. Adiponectin levels were related to glucose tolerance. 相似文献137.
Timothy Sakellaridis Ioannis Panagiotou Themistoclis Georgantas George Micros Dimitra Rontogianni Christos Antiochos 《World journal of surgical oncology》2006,4(1):1-5
Background
Parathyroid carcinoma is a rare cause of primary hyperparathyroidism and may be associated with significant disease related morbidity and mortality. Preoperative diagnosis remains a challenge, which may jeopardize appropriate and successful patient treatment.Case presentation
We report a case of parathyroid carcinoma diagnosed in a 60-year-old woman that presented with a tender nodule located at the left lower thyroid pole and had been present for several years. Ultrasound examination revealed a 2.7 × 1.6 × 2.7 cm mass within the lower left lobe of the thyroid with cystic and solid areas. Lab measurement of the intact PTH level revealed it to be three times the upper limit of normal and the serum calcium level was within normal limits. A left thyroid lobectomy and isthmusectomy was carried out. Histopathological evaluation was diagnostic for a parathyroid carcinoma. At greater than two years of follow-up, the patient has had no evidence of disease recurrence and her serum PTH and calcium levels have remained within normal.Conclusion
Parathyroid carcinoma is a rare endocrine tumor which must be considered in the differential diagnosis of a nodular thyroid mass. En bloc resection remains the treatment of choice for this malignancy. Disease prognosis is influenced by the extent of the initial resection, the presence of metastases, and adequate long-term follow-up. 相似文献138.
Genome-wide analysis of p63 binding sites identifies AP-2 factors as co-regulators of epidermal differentiation 总被引:1,自引:0,他引:1
139.
Disrupting tumor-mediated mechanisms suppressing host immunity represents a novel approach to tumor immunotherapy. Depletion
of regulatory T cells (Tregs) increases endogenous anti-tumor immunity and the efficacy of active immunotherapy in experimental
tumor models. HLA-A2.1/HLA-DR1 (A2.1/DR1) × BALB- neuT
+ (neuT
+) triple transgenic mice represent an improvement over neuT
+ mice for evaluating vaccination regimens to overcome tolerance against HER-2/neu. We questioned whether depletion of Tregs with Denileukin diftitox (Ontak) enhances the efficacy of a therapeutic vaccine
consisting of HER-2(85–94) (p85) CTL and HER-2(776–790) (p776) Th peptides against the growth of TUBO.A2 transplantable tumor
in male A2.1/DR1 × neuT
+ Tg mice. While the therapeutic vaccine primed the tumor-reactive CD8+ CTLs and CD4+ effector T lymphocytes (Teffs) compartment, inducing activation, tumor infiltration, and tumor rejection or delay in tumor
growth, treatment with Ontak 1 day prior to vaccination resulted in enhanced CD4+ and CD8+ T-cell-mediated vaccine-specific immune responses in the periphery. This was closely associated with greater infiltration
and a striking change in the intratumor balance of Tregs and vaccine-specific CTLs/Teffs that directly correlated with markedly
enhanced antitumor activity. The data suggest that Tregs control both CD4+ and CD8+ T-cell activity within the tumor, emphasize the importance of the intratumor ratio of vaccine-specific lymphocytes to Tregs,
and demonstrate significant inversion of this ratio and correlation with tumor rejection during Ontak/vaccine immunotherapy. 相似文献
140.
Apostolidou E Kambas K Chrysanthopoulou A Kourtzelis I Speletas M Ritis K Mitroulis I 《Molecular biology reports》2012,39(5):5503-5510
Familial Mediterranean fever (FMF) is an autoinflammatory disease, characterized by MEFV gene mutations and self-limited recurrent episodes of fever and localized serositis. Complement system is a key regulator
of the inflammatory process. The aim of this study was to investigate the genetic alterations and mRNA expression pattern
of C5aR and C5L2 genes in neutrophils from attack-free FMF patients. No mutations were observed in the two receptors’ genes, while the genetic
alteration observed in the C5aR1 gene was identified as N279 K polymorphic variant. Furthermore, lower mRNA expression of C5L2 gene was observed in neutrophils from FMF patients compared to control subjects. The binding capacity of rhC5a and the ability
to produce reactive oxygen species was similar in neutrophils from healthy subjects and FMF patients and independent of the
presence of N279 K polymorphism or mRNA expression of C5L2. 相似文献