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71.
目的:应用高分辨率荧光显微成像系统采集细胞器探针图像,并与激光共聚焦显微成像系统进行对比。方法:实验于2003-05/2004-01在解放军总医院完成。①实验材料:鼠肺毛细血管内皮细胞株(1H11)由上海复旦张江生物公司提供;荧光探针Rhodamine-123,Lucifer Yellow,DiOC6[3],BODIPY(美国Sigma公司)。②细胞培养及荧光探针染色:细胞培养采用含体积分数为0.2胎牛血清的低糖DMEM培养基,密度5×107L-1。选择Rhodamine-123作为细胞线粒体特异性荧光探针,选择DiOC6[3]作为细胞内质网特异性荧光探针,选择BODIPY作为细胞高尔基体特异性荧光探针,选择Lucifer Yellow作为细胞溶酶体探针。前3个探针在完全避光条件下与培养的细胞共同孵育0.5h,后者则共同孵育15h。③高分辨率荧光成像系统的图像采集:线粒体荧光图像采集,选取经Rhodamine-123共孵育完成的细胞,选择激发滤色镜为BP460-490,吸收滤色镜为BA515,分光镜为DM500,另加一绿通道液晶滤光片,激发出Rhodamine-123的荧光。电荷耦合器件采集图像并送入计算机。重复上述步骤,采用DiOC6[3]标记内质网,BODIPY标记高尔基体,Lucifer Yellow标记细胞溶酶体,激发条件同Rhodamine-123。分别采集同一视野靶细胞DiOC6[3]、BODIPY或Lucifer Yellow的荧光图像,完成全部图像采集并储存在计算机中。④激光共聚焦显微成像系统的图像采集:选择经4种探针染色的靶细胞,使用氩离子激光器在488nm激发Rhodamine-123,Rhodamine-123荧光通过配置有530/60-G发射滤光片的通道1探测。重复上述步骤,在488nm激发DiOC6[3]和BODIPY,在457nm激发Lucifer yellow,3种荧光均由通道1探测,后2个探针的发射滤光片的配置为515/30-G,DiOC6[3]选择530/60-G。由光电倍增管接收信号并传输入计算机成像。结果:①高分辨率荧光成像系统所采集图像,靶细胞中由荧光探针Rhodamine-123染色的线粒体呈多个典型的小棒状或卵圆状,聚集在核周;Lucifer yellow染色的溶酶体呈多个非对称球型,在胞浆内随机分布,颗粒尺寸通常大于线粒体;荧光探针DiOC6[3]着色的内质网占据胞浆的很大空间,以囊状聚集为特征;BODIPY特异性地结合在高尔基体上,荧光图像显示围绕在细胞核周围呈条索状。②与高分辨率荧光成像系统比较,激光共聚焦显微成像系统所采集的图像其荧光强度基本相同,但分辨率低、细节显示模糊、胞浆中细胞器的准确分布信息和形态特征显示效果欠佳。结论:两种荧光显微成像系统均可采集到细胞器探针的荧光图像。但高分辨率荧光成像系统采集的荧光图像具有细节清晰、分辨度高、准确显示胞浆中细胞器的分布信息和形态特征等优点。 相似文献
72.
Studies were carried out in normal male subjects (n = 6, age 20-35 years) to determine the interaction of angiotensin II and plasma sodium on aldosterone secretion. These relations were quantified by elevation of plasma sodium with an infusion of 5% sodium chloride (4 ml/kg/30 min i.v.) with measurements of plasma aldosterone, atrial natriuretic factor (ANF), and arginine vasopressin (AVP) over 3 hours. Two hours before sodium chloride infusion, an intravenous infusion of angiotensin II was begun at 0.5 or 5.0 ng/kg/min and continued throughout the study. Plasma potassium was maintained constant by the addition of potassium to the infusate. NaCl/KCl infusion raised plasma sodium 4 meq/l with no decreases of plasma potassium. Plasma aldosterone averaged 7 +/- 1.8 ng/dl before NaCl infusion in subjects infused with 0.5 ng angiotensin II and was not significantly reduced with sodium chloride infusion. Angiotensin II infused at 5 ng/kg/min resulted in average plasma aldosterone levels of 31 +/- 3.6 ng/dl, which sodium chloride infusion decreased to 16.6 +/- 1.3 ng/dl (p less than 0.05) in 60 minutes. Plasma aldosterone remained depressed for the remaining period of study. Plasma ANF increased from 40 to 60 pg/ml with sodium chloride infusion. We conclude that small physiological elevations of plasma sodium concentrations can signal substantial decreases of plasma aldosterone in normal human subjects in situations where plasma angiotensin II is moderately elevated. The precise mechanisms of these responses remain to be determined. 相似文献
73.
In this study, brain derived neurotrophic factor (BDNF) and nerve growth factor (NGF) were examined at five time points [postnatal day (P)11, 15, 20, 21, and 68 (the latter with or without behavioral testing)] during and after P11-20 (+)-methamphetamine (MA) (10 mg/kg 4 x day) treatment. BDNF in MA-treated animals was elevated on P15 and P20 in the hippocampus but not in the hypothalamus and was unchanged on P11 and P21. On P68 (1 h after Morris water maze testing) MA-treated offspring showed a trend toward higher levels of BDNF in the hippocampus than saline-treated animals. MA treatment increased NGF levels in the hippocampus but only on P20. No effect of MA treatment was observed in the elevated zero maze. MA-treated offspring had increased latencies, cumulative distances, path lengths, and first bearings in the Morris water maze. The findings indicate that early MA exposure induces hippocampal BDNF increases that precede the later emergence of spatial learning deficits. 相似文献
74.
75.
We report the first case of oxaliplatin-related posterior reversible encephalopathy syndrome (PRES) in the medical literature. A 19-year-old woman with metastatic adenocarcinoma of the rectum received modified FOLFOX (5-fluorouracil/oxaliplatin) chemotherapy. Ten days after the fourth treatment, she presented to the hospital with seizures and altered mental status. Magnetic resonance imaging of the brain demonstrated hyperintensity in the white matter of the posterior hemispheres consistent with PRES. Herein, we briefly review the PRES syndrome and its management. 相似文献
76.
Neonatal lupus erythematosus: factors which may lead to clinical disease in the foetus even in the absence of disease in the mother 总被引:1,自引:0,他引:1
Neonatal lupus erythematosus (NLE) occurs in neonates of mothers who, in almost all cases, have auto-antibodies to the SSA/Ro associated proteins, but who may have no clinical disease. However, only a small percentage of mothers with SSA/Ro antibodies have affected babies, predisposing factors specific to the foetus or neonate (i.e. HLA pattern) and/or fetal maternal interactions have been proposed to be important. We present a mother with a family history of autoimmune disease, but without clinical disease, whose baby developed cutaneous NLE. Autoantibody determinations as well as the HLA-DR/DQ were performed in the mother and baby. Factors other than the HLA-DR/DQ status of the mother appear to be important in determining whether or not the neonate will develop NLE. Auto-antibodies to endogenous antigens common to the mother, transiently expressed developmental antigens, and the isotype specificity of transferred antibodies may be important in determining disease in the baby. 相似文献
77.
Terry L. Barrett Henry G. Skelton Kathleen J. Smith Terry C. O'Grady Lynn Proctor-Shipman 《Journal of cutaneous pathology》1996,23(4):378-380
Ossifying fibromyxoid tumor of soft parts is a recently described, rare but morphologically distinctive tumor of soft tissue, including subcutaneous soft tissue. We report a case of ossifying fibromyxoid tumor of soft parts which occurred in the subcutaneous tissue of a 68-year-olcl male, and review the clinical, histologic, and immunohistologic features of this tumor. Ossifying fibromyxoid tumor of soft parts tends to occur in the subcutaneous tissue and have been reported from the head and neck, upper and lower extremities, and trunk. Immunohistologic studies have supported a neural origin. While considered benign, local recurrence after excision is common and these tumors should be excised with clear margins to prevent recurrence. 相似文献
78.
BACKGROUND: Although there have been reports of fly larvae in wounds and as isolated primary infestations, there have been only rare reports documenting reactions to the larvae within the skin in humans and animals. There have been no reports documenting the histopathologic and immunohistochemical characteristics of the inflammatory infiltrate. OBJECTIVE: We present a patient who developed local pruritus, erythema, and swelling approximately three weeks after infestation by a fly larva within the scalp. Histopathologically the biopsy site showed a mixed infiltrate containing lymphoid cells and numerous eosinophils. Immunohistochemical stains showed predominantly CD4+ T cells expressing an ab T-cell receptor (TCR) of which approximately 30% coexpressed T-cell intracellular antigen (TIA) and CD56. In addition, there were approximately 5% of these CD4+ T cells which coexpressed CD30. CONCLUSIONS: Histopathologic and immunohistochemical findings are consistent with an effector cell population of cytotoxic CD4+ T cells that produce a T-helper 2 cytokine pattern. The phenotype of this subset of T cells is unique and among its characteristics is that antigens--usually nonprotein antigens--are presented to these CD4+,TIA+ natural killer (NK)1.1T cells by CD1d molecules. 相似文献
79.
Perspectives in dermatopathology: telomeres and telomerase in ageing and cancer; with emphasis on cutaneous disease 总被引:2,自引:0,他引:2
Shortening of telomeres occurs with cell proliferation and correlates well with ageing in humans. Telomerase is a ribonucleoprotein, and is the body's most widely studied mechanism for extension of telomeres to circumvent cellular ageing. Telomerase levels remain at low or unmeasurable levels in most somatic cell populations with only a few exceptions. However, in transformed cell populations, upregulation of telomerase or some other mechanism for telomere extension is required for immortality. The telomere-telomerase system has been proposed to be an adaptation of organisms with prolonged lifespan to avoid malignant tumors, at the cost of the cellular dysfunctions associated with the aged phenotype. Therapies to modulate telomere length and telomerase levels hold promise for therapy of cancer and ageing as well as for genetic conditions that predispose to an aged phenotype. 相似文献
80.
Jacques Marcotte Frederick S. Skelton Michel G. Côté Hanspeter Witschi 《Toxicology and applied pharmacology》1975,33(2):231-245
Rats were exposed to the smoke produced by burning four cigarettes of marijuana or of marijuana placebo material. Six hours later, maximally stimulated aryl hydrocarbon hydroxylase (AHH) activity was observed in the lung. Marijuana placebo material also induced pulmonary AHH activity. Actinomycin D (1 mg/kg) and cycloheximide (2 mg/kg), given ip 1 hr before exposure to marijuana smoke, partially blocked AHH induction. If rats were exposed repeatedly to marijuana smoke, they showed higher activities of pulmonary AHH within 6 hr of the last exposure than did animals exposed for the first time. Inhalation of marijuana smoke increased the number and size of debris-filled vacuoles in alveolar macrophages and in the ciliated cells of the bronchiolar epithelium. Smoke condensate from the marijuana material used in these studies contained 0.45 ng/mg of benzo(a)pyrene. 相似文献