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排序方式: 共有4364条查询结果,搜索用时 15 毫秒
41.
Nirmala Chandrasekar Sanjeeva Mohanam S Sajani Lakka Dzung H Dinh William C Olivero Meena Gujrati Jasti S Rao 《Clinical cancer research》2003,9(6):2342-2349
PURPOSE: Tumor vasculature provides the infrastructure by which malignant tissue can be nourished; therefore, targeting angiogenesis may be an effective means of treating cancer. We showed previously that SNB19 glioblastoma cells modulate bovine retinal endothelial cells in cocultures to form capillary-like network structures, that matrix metalloproteinase-9 (MMP-9) expression is critical for endothelial morphogenesis, and that MMP-9 expression in glioblastoma cells is regulated by extracellular signal-regulated kinase-1 (ERK-1). In the present study, we investigated whether interfering with the activation of this mitogen-activated protein (MAP) kinase would repress MMP-9 synthesis and inhibit capillary formation. EXPERIMENTAL DESIGN: Cocultures of bovine retinal endothelial and SNB19 cells were analyzed for MMP-9 secretion, and phospho- and total ERK levels. These cocultures were treated with PD98059, a specific inhibitor of MAP/ERK kinase 1, or transfected with dominant-negative ERK-1 mutant containing expression vector. Alterations in capillary-like structure formation, and actin cytoskeleton and secretion of vascular endothelial growth factor (VEGF), MMP-9, and tissue inhibitor of metalloproteinase-1 were determined by immunofluorescence, gelatin zymography, and Western blotting. RESULTS: We found that inhibition of the ERK-1/2 pathway with PD98059 abrogated glial cell-mediated capillary formation by the endothelial cells and reduced the levels of MMP-9 in the coculture. Strikingly, the abrogation of MAP kinase signaling by a dominant-negative ERK-1 mutant inhibited glial-induced capillary network formation by reducing VEGF levels and MMP-9 activity and increasing the levels of tissue inhibitor of metalloproteinase-1. Inhibition of ERK activity also disrupted the formation of the actin cytoskeleton, a prerequisite for endothelial cell migration. CONCLUSION: The mechanism underlying activation of ERK is involved in reorganization of the actin cytoskeleton, and induction of VEGF and MMP-9, thereby stimulating endothelial cell morphogenesis. These studies clearly provide experimental evidence that ERK inhibition diminishes glial-induced endothelial-cell morphogenesis; therefore, interfering with ERK signaling may be a viable approach to target angiogenesis. 相似文献
42.
H O Goyal T D Braden C S Williams P Dalvi M Mansour J W Williams 《Toxicological sciences》2005,87(1):242-254
We previously reported that diethylstilbestrol (DES) or estradiol valerate (EV) exposure at a dose of 0.10-0.12 mg/kg, or higher, per day, on alternate days, from postnatal days 2-12, resulted in abnormal penis development and infertility (H. O. Goyal et al., 2005, J. Androl. 26, 32-43). The objective of this study was to identify a critical developmental period(s) during which EV exposure results in the observed penile abnormalities. Male pups received EV at a dose of 0.10-0.12 mg/kg on postnatal day(s) 1, 1-3, 4-6, 1-6, 7-12, 13-18, 19-24, or 25-30. Fertility was tested at 102-115 days of age and tissues were examined at 117-137 days. Both penile morphology and fertility were unaltered in rats treated with EV after 12 days of age. Conversely, except in rats treated on postnatal day 1 only, none of the males treated prior to 12 days of age sired pups, and all had abnormal penises, including varying degrees of abnormal accumulation of fat cells and loss of cavernous spaces and smooth muscle cells in the corpora cavernosa penis, which were maximal in the 1-6-day group. Also, the preputial sheath was partially released or its release was delayed, and the weight of the bulbospongiosus muscle was significantly reduced. Plasma testosterone (T) in the 1-6- and 4-6-day groups and intratesticular T in the 4-6-day group were significantly lower. The testosterone surge, characteristic of controls in the first week of life, was suppressed in the 1-3-day group. Estrogen receptor alpha mRNA expression was enhanced in the body of the penis in the 1-3-day group, but not in the 13-18-day group. Hence, EV exposure prior to 12 days of age (as short as 1-3 days postnatal), but not after 12 days of age, results in long-term abnormal penile morphology, characterized by abnormal accumulation of fat cells in the corpora cavernosa penis and, consequently, loss of fertility. 相似文献
43.
Sham L. Singla Yogender Singh Kadian Naveen Malhotra Ashish Goyal 《Indian journal of otolaryngology and head and neck surgery》2004,56(2):131-132
Neurilemmoma of the cervical sympathetic chain is a rare nerve tumour. Less than 40 confirmed cases have been reported in
the literature.1 2 Sometimes they can he mistaken as carotid body tumour but usual presentation of these lesions is an asymptomatic
neck mass. Because of the rarity of the tumour we report another case of neurilemmoma arising from cervical sympathetic chain
in a 19 years old male. 相似文献
44.
Histological and immunohistochemical study of estrogen and progesterone receptors in normal human breast tissue in adult age groups vulnerable to malignancy
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R. Goyal T. Gupta R. Gupta A. Aggarwal D. Sahni G. Singh 《Clinical anatomy (New York, N.Y.)》2016,29(6):729-737
Analysis of receptor status has become standard procedure for assessing breast cancer patients. Estrogen causes epithelial proliferation in breast tissue via the estrogen receptor (ER). The progesterone receptor (PR) is also regulated by the estrogen gene. Analyzing ER and PR together gives information regarding the likely response of carcinoma patients to hormonal therapy. The aim of the present study was to record the expression patterns of ER and PR in normal mammary tissue in different age groups to provide reference data to facilitate histological diagnosis. Breast tissues from the upper outer quadrant of each side of 27 adult female cadavers were examined after H & E staining. ER and PR were identified and examined by immunohistochemistry. The percentage area occupied by parenchyma relative to stromal tissue was calculated in different age groups and was about 4:6, 3.5:6.5, 3:7, 2:8, and 1.5:8.5 in the 3rd, 4th and 5th, 6th, 7th, 8th and 9th, and 10th decades of life, respectively. Both ER and PR were present in all age groups and the numbers of both receptors were maximal during the 4th decade. The distribution and staining patterns for both ER and PR were recorded in different age groups. The contiguous pattern of ER, which is considered pathognomonic of breast carcinoma, was not seen except in one case in the 6th decade. Moderately stained ER and PR receptor sites predominated throughout. The study of normal breast tissue of similar age might provide comparisons that will help histopathologists to make clinical diagnoses from breast biopsies. Clin. Anat. 29:729–737, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
45.
Local anesthetics are one of the most commonly used drugs in the field of medicine. Yet little is known about the systemic toxicity that can occur with their overdose. In the last few years, a lot of research has taken place understanding the etiology of the Local anesthetics systemic toxicity (LAST) and the role of lipid emulsion in treating it. There is a need to increase the awareness about LAST and establish a protocol to treat any serious neuro or cardiotoxicity. 相似文献
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