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1.
The interactions between steroid and nonsteroid hormones in the prostate are of special interest during the growth phase of the gland. The purpose of this work is to study the influence of prolactin (PL), with or without androgenic blockade, on epithelial cells from peripubertal rat ventral prostate. Twenty male peripubertal Sprague‐Dawley rats were grouped as controls, or treated with cyproterone acetate (CA), CA plus PL (CA‐PL), or PL. The total number (N total) of epithelial cells, and their labeling indices to proliferative cell nuclear antigen (LI PCNA), apoptosis (LI apoptosis) and androgen receptors (LI AR) were measured. CA and PL treatment significantly decrease the N total, but the LI PCNA was unchanged. We have observed a greater LI apoptosis in pharmacologically castrated animals without PL than in the rats with androgenic blockade with PL. The LI AR does not change with CA treatment in the ventral region, but the PL significantly increases it. Androgenic blockade and PL decrease the number of epithelial cells from the ventral prostate. These changes are not attributable to the decrease of cell proliferation, rather to the increase of epithelial apoptosis. The increase of cells expressing AR after treatment with PL might be attributed to the decrease of testosterone secretion caused by the hyperprolactinemia. PL does not modulate the size of the ventral prostate in prepubertal rats. Anat Rec, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

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To investigate the mechanism of oridonin (ORI)‐induced autophagy in prostate cancer PC‐3 cells, PC‐3 cells cultured in vitro were treated with ORI, and the inhibitory ratio of ORI on PC‐3 cells was assayed by 3‐4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide. The ultrastructural changes of the cells were observed under light microscope, scanning electron microscope (SEM), and transmission electron microscope (TEM). Acridine orange (AO) staining was used to observe the acidic vesicular organelles (AVOs). The level of autophagy‐related proteins, MAP1‐LC3, was detected by Western Blot, and RT‐PCR was used to detect the level of mRNA of beclin 1. After ORI treatment, the proliferation of PC‐3 cells was inhibited significantly in a concentration and time‐dependent manner. SEM examination revealed cellular shrinkage and disappearance of surface microvilli in ORI‐treated cells. Under TEM examination, the nuclei exhibited chromatin condensation and the appearance of a large number of autophagosomes with double‐membrane structure in cytoplasm. AO staining showed the existence of AVOs. The expression of LC3 and the mRNA level of beclin 1 was increased by ORI. Furthermore, autophagy inhibitor 3‐methyladenine reversed the increase of beclin 1 mRNA. The growth of PC‐3 cells was inhibited, and autophagy was induced by ORI, indicating ORI may have a potential antitumor effect. Anat Rec, 2012. © 2011 Wiley Periodicals, Inc.  相似文献   

4.
Poorly differentiated neuroendocrine carcinomas (PDNECs) of the kidney are extremely rare high-grade cancers accounting for only 42 cases reported in the literature. In this paper, we describe the morphological, immunohistochemical, ultrastructural, and for the first time, cytogenetic features of a renal PDNEC. In addition, we have reviewed the literature and compared the published clinicopathological data with our morphological and genetic results. The tumor arose within the kidney parenchyma and showed the typical histological features of a pure small cell PDNEC. Fluorescence in situ hybridization study demonstrated a complex chromosomal assessment indicative of a high degree of chromosome instability with gain of multiple chromosomes, loss of p53, and amplification of myc gene. These results suggest that renal PDNEC has a different genetic background to renal clear cell carcinoma, mainly characterized by the loss of the short arm of chromosome 3. Conversely, genetic alterations seem to resemble those of type 2 papillary renal cell carcinoma. The review of the literature demonstrated that PDNECs are associated with poor prognosis and that parenchymal tumors show some differences from those arising in the pelvis, in that parenchymal tumors are purely neuroendocrine while pelvic tumors are mostly mixed neuroendocrine–exocrine neoplasms.  相似文献   

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以 SD大鼠为实验对象 ,从其骨髓分离出骨髓基质细胞 (BMSC) ,利用 L IF、b FGF、RA等增殖及分化诱导因子和神经干细胞培养液进行培养、分化诱导 ,观察 SD大鼠骨髓基质细胞体外培养的生长行为及扩增、分化情况。我们观察到 ,分离得到的骨髓基质细胞在体外培养中能形成细胞克隆团 ,这些具有克隆能力的骨髓基质细胞经传代后 ,其数量明显多于原代培养 ;BMSC经持续培养具有增殖能力以及分化为组织细胞的潜能 ,其分化细胞形态多样 ,包括胶质细胞样细胞和神经元样细胞。实验结果证明 ,骨髓基质细胞具有较强的自我更新的能力和多分化能力 ,也说明本实验所采用的细胞培养方法适用于骨髓基质细胞的体外生存与扩增。骨髓基质细胞较容易取材、体外培养和扩增 ,并具有多向分化潜能 ,在合适的诱导分化条件下 ,可分化出神经细胞 (神经元和神经胶质细胞 ) ,是理想的种子细胞  相似文献   

6.
Little is known about the effect of antiandrogens and estrogens on the adrenal cortex. To investigate their influence the antiandrogen Cyproterone acetate (CP) and the estrogen estradiol benzoate (EB) were applied separately to matched groups of animals. While EB affects the hypothalamic-pituitary axis via a negative feedback mechanism, CP has a competitive influence on peripheral androgen receptors and also affects the central regulatory mechanism through its gestagenic component.48 male rats were divided in 6 groups, two for CP, two for EB, two control, each pair consisting of half young, half adult animals. Animals were killed on the 36th day of the assay. The histologic slides of adrenal tissue were evaluated using microphotographs enlarged by copyprint to 800fold magnification.The effects of the two drugs are recorded separately for the three zones of the Adrenal cortex, Z. glomerulosa (ZG), Z. fasciculata (ZF) and Z. reticularis (ZR): EB provokes atrophy of ZG in young rats, whereas no effects of CP on this zone are registered morphometrically in young nor in adult animals. ZF shows marked regressive transformation and CP, stronger in adult than in young animals. EB causes regressive transformation only in young rats. The effects of CP on ZR in different in young and adult rats, the young ones showing marked atrophy, the adult group demonstrating an increase of cell volume, — EB-treated rats, both young and adult, show a volume increase of reticularis cells.ZG-atrophy under EB is not adequately explained by the morphological methods used in our assay. The regressive transformation of ZF in young and adult rats seems to be due to an additional corticotropic action of CP, whereas the progressive transformation under EB is probably due to the paradoxical effect of estrogens with a positive feedback mechanism. The diversity of ZR reactions to CP is explained by different steroid metabolisms in the groups. The volume increase of reticularis cells under EB may be due to an increased storage of steroid precursors.  相似文献   

7.
Although numerous investigators in 1970s to 1980s have reported the distribution of LH‐RH nerve fibers in the median eminence, a few LH‐RH fibers have been shown to be present in the pars tuberalis. The significance of the finding remains to be elucidated, and there are few studies on the distribution of LH‐RH neurons in the pars tuberalis, especially in the dorsal pars tuberalis (DPT). Adult male Wistar‐Imamichi rats were separated into two groups: one for electron microscopy and the other for immunohistochemistry to observe LH‐RH and neurofilaments. Pituitary glands attached to the brain were fixed by perfusion, and the sections were prepared parallel to the sagittal plane. The typical glandular structure of the pars tuberalis was evident beneath the bottom floor of the third ventricle, and the thick glandular structure was present in the foremost region. Closer to the anterior lobe, the glandular structure changed to be a thin layer, and it was again observed at the posterior portion. Then the pituitary stalk was surrounded with the dorsal, lateral, and ventral pars tuberalis. LH‐RH and neurofilaments fibers were noted in the bottom floor, and some of them vertically descended to the gland. Adjacent to the glandular folliculostellate cells in the pars tuberalis, Herring bodies with numerous dense granules invading into the gland were present between the pituitary stalk and DPT. It was postulated that the “message” carried by LH‐RH might have been transmitted to the cells in the DPT to aid in the modulation of LH release. Anat Rec, 290:1388–1398, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   

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It has been shown that human and cat epithelial cell rests of Malassez (ERM) consist of heterogeneous cell populations. Immunohistochemical and immunoelectron microscopic analyses have verified the presence of neuroendocrine and Merkel‐like cells in both of these epithelia. During experimental orthodontic tooth movement, immunocompetent cells have also been found in the vicinity of ERM in rat periodontal ligament (PDL), but have not been characterized in normal rat PDL. The aim of this study was to investigate the presence and distribution of MHC class II antigen presenting cells by using OX6 antibody in ERM of rat molars by light and transmission electron microscopy. Immunohistochemical and immunoelectron microscopic observations of rat maxillary molars confirmed the presence of OX6‐positive cells in contact with ERM. Some immunopositive cytoplasmic processes containing vesicles interdigitated with cells of the Malassez epithelial clusters. Based on these findings it can be concluded that immunocompetent cells are localized close to Malassez epithelial clusters in normal rat PDL. Furthermore, the ultrastructural evidences indicate a possible interaction between the epithelial and immunocompent cells and suggest morphological and functional properties for ERM. Anat Rec, 291:242–253, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   

10.
This study aimed to evaluate by immunohistochemistry and transmission electron microscopy (TEM) the morphological features of the oral mucosa endothelial tip cells (ETCs) and to determine the immune and ultrastructural patterns of the stromal nonimmune cells which could influence healing processes. Immune labeling was performed on bioptic samples obtained from six edentulous patients undergoing surgery for dental implants placement; three normal samples were collected from patients prior to the extraction of the third mandibular molar. The antibodies were tested for CD34, CD117(c‐kit), platelet derived growth factor receptor‐alpha (PDGFR‐α), Mast Cell Tryptase, CD44, vimentin, CD45, CD105, alpha‐smooth muscle actin, FGF2, Ki67. In light microscopy, while stromal cells (StrCs) of the reparatory and normal oral mucosa, with a fibroblastic appearance, were found positive for a CD34/CD44/CD45/CD105/PDGFR‐α/vimentin immune phenotype, the CD117/c‐kit labeling led to a positive stromal reaction only in the reparatory mucosa. In TEM, non‐immune StrCs presenting particular ultrastructural features were identified as circulating fibrocytes (CFCs). Within the lamina propria CFCs were in close contact with ETCs. Long processes of the ETCs were moniliform, and hook‐like collaterals were arising from the dilated segments, suggestive for a different stage migration. Maintenance and healing of oral mucosa are so supported by extensive processes of angiogenesis, guided by ETCs that, in turn, are influenced by the CFCs that populate the stromal compartment both in normal and reparatory states. Therefore, CFCs could be targeted by specific therapies, with pro‐ or anti‐angiogenic purposes. Anat Rec, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   

11.
The aim of the present study was to investigate changes occurring in the number of beta cells, as well as the expressions of Ngn‐3, nestin and Pdx‐1 of pancreatic progenitor cells in the pancreas of experimentally‐induced adult diabetic rats and to determine the effect of orally‐administered lycopene on these changes. Following the administration of 50 mg/kg streptozotocin to rats, four groups of animals were established: control + corn oil, control + lycopene, diabetic + corn oil and diabetic + lycopene. The animals in the control + lycopene and diabetic + lycopene groups received 4 mg/kg lycopene for a period of four weeks. The expressions of insulin, Ngn‐3, nestin, and Pdx‐1 were determined through immunohistochemistry in sections taken from pancreas tissue samples at the end of the experiment. The number of insulin‐positive cells was found to be significantly low in the diabetic groups compared to the control groups. In addition, the presence of Ngn‐3 and nestin‐positive cells within the exocrine pancreas surrounding the islands was noted in the diabetic groups. Lycopene, in general did not have any effect in any of the parameters analyzed in the present study. It is suggested that these cells would function as stem cells to replace the lost beta‐cell population. It is also suggested that it is possible to demonstrate the antioxidant effects of lycopene in the pancreas of diabetic rats by increasing the dose and duration of lycopene administration. Anat Rec, 300:2200–2207, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   

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The photovoltaic performances of dibenzo[def,mno]chrysene‐based polymer (poly(2,2′‐thiophenevinylenthiophene‐4,10‐[6,12‐bis(2‐decyltetradecyloxy)‐dibenzo[def,mno]chrysene]) (PTVTC) or poly(4,10‐bithiophene‐6,12‐bis(2‐decyltetradecyloxy)‐dibenzo[def,mno]chrysene) (PTTC)) solar cells as a function of thermal annealing temperatures from 100 to 180 °C are reported. Interestingly, the solar cells with PTTC containing two thiophene units, have superior thermal stability compared to the PTVTC:[6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) solar cells, in which the PTVTC has two thiophene and vinyl groups. Atomic force microscopy, transmission electron microscopy, and X‐ray diffraction demonstrate that morphological stability of PTTC:PC71BM blend films conduces thermally stable photovoltaic performances of PTTC solar cells. Therefore, the PTTC:PC71BM bulk heterojunction solar cells have highly stable efficiency, retaining 97% of its original power conversion efficiency value without PCBM clusters in the blend films even at elevated temperatures. There have been no previous reports on the thermal stability aspect of dibenzo[def,mno]chrysene‐based polymer solar cells so far.

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14.
Mutations in genes encoding proteins of the smooth muscle cell (SMC) contractile apparatus contribute to familial aortic aneurysms. To investigate the pathogenicity of these mutations, SMC are required. We demonstrate a novel method to generate SMC‐like cells from human dermal fibroblasts by transdifferentiation to study the effect of variants in genes encoding proteins of the SMC contractile apparatus (ACTA2 and MYH11) in patients with aortic aneurysms. Dermal fibroblasts from seven healthy donors and cells from seven patients with MYH11 or ACTA2 variants were transdifferentiated into SMC‐like cells within a 2‐week duration using 5 ng/ml TGFβ1 on a scaffold containing collagen and elastin. The induced SMC were comparable to primary human aortic SMC in mRNA expression of SMC markers which was confirmed on the protein level by immunofluorescence quantification analysis and Western blotting. In patients with MYH11 or ACTA2 variants, the effect of intronic variants on splicing was demonstrated on the mRNA level in the induced SMC, allowing classification into pathogenic or nonpathogenic variants. In conclusion, direct conversion of human dermal fibroblasts into SMC‐like cells is a highly efficient method to investigate the pathogenicity of variants in proteins of the SMC contractile apparatus.  相似文献   

15.
An alternating copolymer (PBDTC10DBT) of benzo[1,2‐b:3,4‐b′]dithiophene (BDT) as donor and 4,7‐di(3‐decylthiophen‐2‐yl)‐2,1,3‐benzothiadiazole (C10DBT) as acceptor is designed and synthesized. In order to investigate the effect of the 1,8‐diiodooctane (DIO) additive on the morphology and photovoltaic performance, polymer solar cells (PSCs) based on PBDTC10DBT:[6,6]‐phenyl‐C61‐butyric acid methyl ester (PC61BM) are fabricated. The morphology of blend films and the interpenetrating network between the donor and the acceptor is examined using atomic force microscopy and scanning electron microscopy. This work shows that the PBDTC10DBT:PC61BM blend films with added DIO (3%, v/v) have improved absorption and controlled phase separation. Morphology with a domain size of 20–30 nm that forms in the DIO system is proposed to facilitate charge transport and minimize charge carrier recombination, which are the main reasons why the power conversion efficiency of the PSCs is improved from 1.93% (without DIO) to 2.23% (with DIO).

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16.
Objective: To study the effect of GnRH-II on the cell proliferation, apoptosis and secreting vascular endothelial growth factor (VEGF) of ectopic, eutopic and normal endometrial stromal cells (ESC) from patients with or without endometriosis (EMs) in vitro. Methods: The ectopic, eutopic and normal ESC were isolated, cultured and identified, then added 0 M, 10-10 M, 10-8 M, 10-6 M GnRH-II. The growth and proliferation of three ESC were measured by MTT assay; the cell apoptosis were detected with the method of Hoechst staining and Flow Cytometry test; ELISA was used to measure the VEGF concentration change by three ESC secretion. Results: GnRH-II inhibited the proliferation of ectopic, eutopic ESC from patients with endometriosis and normal ESC from control patients, in a dose- and time-dependent manner (P<0.05); GnRH-II increased the apoptotic rate of three ESC in a dose-dependent manner (P<0.05); The concentration of VEGF in three ESC was significantly decreased after the treatment of GnRH-II, in a dose-dependent manner (P<0.01); And these above effects were the strongest on the ectopic than on the eutopic or normal, there were statistical significance (P<0.05); and three was no significantly difference between the eutopic and normal (P>0.05). Conclusions: GnRH-II significantly inhibited the cell proliferation, induced cell apoptosis and decreased the VEGF secreting of ectopic, eutopic and normal ESC in EMs in vitro, and these effects were the strongest on ectopic ESC, which suggested that GnRH-II may become a new effective treatment for endometriosis.  相似文献   

17.
Rat models are commonly used to investigate the pathophysiological pathways and treatment outcomes after spinal cord injury (SCI). The high incidence of fall‐induced SCI in older adults has created a need for aging models of SCI in rats to investigate potential age‐related differences in SCI severity and outcomes. The aims of this study were to determine the influences of age and vertebral level on the geometries of the cervical spinal cord and spinal column in a rat model. Three young (3 months) and three aged (12 months) Fischer 344 rats were imaged in a high field (7 T) small‐animal magnetic resonance imaging system. All spinal cord geometry variables (including depth, width, and axial cross‐sectional area) and one spinal canal variable (depth) were significantly larger in the aged specimens by an average of 8.1%. There were main effects of vertebral level on all spinal cord variables and four spinal canal variables with values generally larger at C4 as compared to C6 (average increases ranged from 5.7% to 12.9% in spinal cord measures and 5.4% to 6.8% in spinal canal measures). High inter‐rater reliability between two measurers was observed with a mean intraclass correlation of 0.921 and percent difference of 0.9% across all variables measured. This study clearly demonstrates that cervical spinal cord geometry changes between the ages of 3 and 12 months in Fischer 344 rats. This information can aid in the planning and interpretation of studies that use a rat model to investigate the influence of age on cervical SCI. Anat Rec, 297:1885–1895, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

18.
Derivation of periosteal and endosteal contours taken from transversal long bone cross‐sections limits the accuracy of calculated biomechanical properties. Although several techniques are available for deriving both contours, the effect of these techniques on accuracy of calculated cross‐sectional properties in non‐adults is unknown. We examine a sample of 86 non‐adult femora from birth to 12 years of age to estimate the effect of error in deriving periosteal and endosteal contours on cross‐sectional properties. Midshaft cross‐sections were taken from microCT scans and contours were derived using manual, fully automatic, spline, and ellipse techniques. Agreement between techniques was assessed against manually traced periosteal and endosteal contours using percent prediction error (%PE), reduced major axis analysis, and limits of agreement. The %PEs were highest in the medullary area and lowest in the total area. Mean %PEs were sufficiently below the 5% level of acceptable error, except for medullary areas, but individual values can greatly exceed this 5% boundary given the high standard deviation of %PE means and wide minimum–maximum range of %PEs. Automatic processing produces greater errors than does combination with manual, spline, and ellipse processing. Although periosteal contour is estimated with stronger agreement compared with endosteal contour, error in deriving periosteal contour has a substantially greater effect on calculated section moduli than does error in deriving endosteal contours. We observed no size effect on the resulting bias. Nevertheless, cross‐sectional properties in a younger age category may be estimated with greater error compared with in an older age category. We conclude that non‐adult midshaft cross‐sectional properties can be derived from microCT scans of femoral diaphyses with mean error of < 5% and that derivation of endosteal contour can be simplified by the ellipse technique because fully automatic derivation of endosteal contour may increase the resulting error, especially in small samples.  相似文献   

19.
To elucidate the mechanism of vitamin A enhancing the production of antibody, we examined the expression and distribution of retinoic acid receptors mRNA in lymph nodes of young children ( ≤ 5 years of age), and investigated the affection of all-trans-retinoic acid on the maturation and activation of the B cells isolated from the lymph nodes and cultured in vitro. Twenty-four normal lymph nodes were collected. By in situ hybridization, we found that all six retinoic acid receptor genes expressed and distributed widely in the lymph nodes, and the levels of mRNA for retinoic acid receptor genes (detected by RT-fluorescent quantitative PCR) were increased with the development of children. In vitro culture, all-trans retinoic acid promoted the maturation and activation of the B cells from the lymph nodes. Thus, promotion on B cells in lymph node may be the important mechanism of vitamin A reinforcing the humoral immunity in young children.  相似文献   

20.
The apolipoprotein E (APOE) gene is involved in lipid transport. A common polymorphism in this gene with the APOE*2, APOE*3, and APOE*4 alleles influences plasma levels of apolipoprotein E and cholesterol. Besides its role in lipid transport, the APOE*4 allele is a genetic risk factor for Alzheimer disease (AD). Recently, a polymorphism in the APOE promoter region was found to be involved in plasma apolipoprotein E levels and was found associated with AD. We studied the effect of this ?491A/T promoter polymorphism on plasma apolipoprotein E levels and risk for AD in a population‐based case‐control study. We found that there was a modest but statistically significant effect of the ?491A/T polymorphism on plasma apolipoprotein E levels independent of the APOE genotype. The lowest plasma levels were measured for the AA genotype, highest levels for the TT genotype, and intermediate levels for the heterozygotes. There was a small effect of the ?491 AA genotype on AD risk that disappeared after adjusting for APOE genotypes. Our data suggest that the ?491A/T polymorphism has an APOE genotype‐independent effect on plasma apolipoprotein E levels but no APOE‐independent effect on AD risk. © 2002 Wiley‐Liss, Inc.  相似文献   

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