不同发育阶段人表皮干细胞端粒酶反转录酶表达的比较

目的:目前已知端粒酶活性的丧失及其增殖相关基因表达的改变是造成多种成体干细胞体外复制和扩增受限的主要原因,而端粒酶反转录酶对端粒酶活性起关键作用。体外分离培养人胚胎、少儿、成人3种不同皮肤来源的表皮干细胞,对比观察不同发育阶段端粒酶反转录酶表达的差异。方法:实验于2005-09/2007-04在南昌大学第一附属医院烧伤研究所完成。①对象:因创伤等原因致意外流产的妊娠24～26周龄胎儿皮肤标本,4～12周岁少儿及25～45岁成年人烧伤整形植皮手术剩余皮片标本,分别由南昌大学第一附属医院产科、烧伤科提供,产妇与烧伤患者对治疗及实验均知情同意,实验经医院医学伦理委员会批准。②实验方法:取胎儿、少儿和成年人的全层皮肤,用胰蛋白酶和EDTA联合消化法分离表皮,胶原快速贴附法纯化人表皮干细胞,用未黏附的角质细胞作为对照,以含表皮生长因子、角质细胞无血清培养液组成的表皮干细胞培养基进行体外培养。③实验评估:通过β_1整合素、角蛋白19、p63免疫细胞化学染色对培养细胞进行鉴定,计算克隆形成率。以免疫细胞化学染色法和图像定量分析法检测3种不同皮肤来源的表皮干细胞端粒酶反转录酶的表达差异。结果:①细胞生长特征:分离培养的人表皮干细胞呈明显克隆性生长,克隆形成率高于角质细胞对照组(P<0.05)。②表皮干细胞的鉴定:细胞克隆经免疫细胞化学染色后,β_1整合素、角蛋白19、p63均呈阳性表达。③端粒酶反转录酶免疫细胞化学染色及定量表达:不同皮肤来源的表皮干细胞端粒酶反转录酶均呈阳性,但表达强度不同,人胚胎>少儿>成人。3种皮肤来源的表皮干细胞平均吸光度值和阳性面积值均随年龄增加而逐渐降低,人胚胎>少儿>成人(P<0.05)。结论:人胚胎、少儿、成人皮肤来源的表皮干细胞均有端粒酶反转录酶表达,其表达强度依次减弱。提示诱导和增强端粒酶反转录酶的表达对维持表皮干细胞在体外自我更新和增殖能力可能具有重要意义。     

4种氟喹诺酮液体制剂降解析因试验

模拟4种喹诺酮输液剂及滴眼剂在不同pH和离子强度的条件下,考察了光、pH以及离子强度分别对诺氟沙星(NFX)、氧氟沙星(OFX)、环丙沙星(CPX)、洛美沙星(LEMX)降解程度的影响,应用2³析因试验方法,经F检验确证:NFX,OFX,CPX,LEMX离子强度影响均不显著,光影响均极显著;pH对NFX和LEMX影响不显著,对OFX和CPX影响极显著;OFX和CPX由光及pH二因素交互作用影响极显著,NFX和LEMX由光及pH二因素交互作用影响不显著。     

Correlates of Osteoprotegerin Levels in Women and Men

Osteoprotegerin (OPG) is a potent antiresorptive molecule that binds the final effector for osteoclastogenesis, receptor activator of NF-kB ligand (RANK-L). OPG production is regulated by a number of cytokines and hormones, including sex steroids, but there are few data on age and gender effects on circulating serum OPG levels, as well as possible relationships between OPG levels and bone turnover markers or bone mineral density (BMD). Thus, we measured serum OPG levels in an age-stratified, random sample of men (n= 346 age range, 23–90 years) and women (n= 304; age range 21–93 years) and related them to sex steroid levels, bone turnover markers and BMD. Serum OPG levels increased with age in both men (R= 0.39, p<0.001) and women (R= 0.18, p<0.01). Premenopausal women had higher OPG levels than men under age 50 years (171 ± 6 pg/ml vs 134 ± 6 pg/ml, respectively, p<0.001), whereas serum OPG levels were no different in postmenopausal women compared with men = 50 years (195 ± 7 pg/ml vs 188 ± 7 pg/ml, respectively, p= 0.179). OPG levels correlated inversely with serum bioavailable testosterone levels in men = 50 years (R=–0.27, p<0.001), but no associations were present with either estrogen or testosterone levels in the women. In the men, there was a trend for OPG levels to be associated positively with bone resorption markers and inversely with BMD. Collectively, the gender difference in OPG levels suggests that sex steroids may regulate OPG production in vivo, as has been found in vitro. Moreover, OPG production may also rise with increases in bone turnover, probably as a homeostatic mechanism to limit bone loss. Further studies directly testing these hypotheses should provide additional insights into the potential role of OPG in bone loss related to aging and sex steroid deficiency. Received: 14 August 2001 / Accepted: 20 November 2001     

Neighbourhood deprivation and self-rated health: the role of perceptions of the neighbourhood and of housing problems

It has been known for a long time that people living in socially and economically deprived neighbourhoods generally experience poorer health. However, it is often not clear what processes underlie the relationship between neighbourhood deprivation and individual health. In this study we explore the association between neighbourhood socio-economic status and self-rated health using the Caerphilly Health and Social Needs Survey (n=10,892). We found that the association between neighbourhood deprivation and self-rated health was substantially reduced after adjusting for individual socio-economic status, but remained statistically significant. This suggests that the health effects of neighbourhood deprivation are partly contextual. We also found that the association between neighbourhood deprivation and self-rated health was further attenuated when controlling for perceptions of the neighbourhood and of housing problems, suggesting that these variables may play a role in mediating the health effects of neighbourhood deprivation. The implications of the results are that health policy should target 'places' as well as 'people'; and that policies aimed at improving the quality of housing, access to amenities, neighbourhood safety, and social cohesion may help to reduce health inequalities.     

蝙蝠葛碱和粉防己碱对[3H]WEB 2086与体外牛脑前动脉平滑肌细胞结合的影响(英文)

用标记的血小板活化因子拮抗剂[³H]WEB 2086,在培养的牛脑前动脉平滑肌细胞上鉴定了血小板活化因子受体。结果表明在25℃时该细胞上存在两种与配基具有不同亲和力的受体结合位点,其中K_d-1=22.8±5.0 nmol·L^-1,K_d-2=186+20.5 nmol·L^-1;B_max-1=2.1±0.3 pmol/10⁴细胞,B_max-2=12.1±1-5 pmol/10⁶细胞。蝙蝠葛碱和粉防己碱均能抑制[³H]WEB2086与上述细胞的结合。     

The tumour stroma of oral squamous cell carcinomas show increased vascularity compared with adjacent host tissue.

For tumours to grow they must acquire an adequate blood supply, and the use of drugs to inhibit tumour vascularization is one promising approach to anti-cancer therapy. Clear information is therefore required on the vascular architecture of human tumours and animal tumour models used for testing anti-angiogenic therapies. Many previous studies on animal tumour models have shown that carcinomas are least vascular in their centres and that host tissues become more vascular with proximity to the tumour. However, we have previously found that many human colorectal carcinomas do not show this pattern. The present study on human oral squamous cell carcinomas (SCCs) again reveals significant differences. Paraffin sections from 24 SCCs were immunostained using the QBEnd-10 monoclonal antibody to demonstrate blood vessels, and these were quantified by interactive morphometry using a Kontron Videoplan system. In most carcinomas, viable tumour tissue was no less vascular in the tumour centre than in the tumour periphery. Although tumours are known to release angiogenic factors, viable tumour tissue was less vascular than adjacent host tissues. However, the tumour stroma, by itself, was more vascular than adjacent host tissues. Host tissue adjacent to tumour showed no obvious increase in vascular density with increasing proximity to the tumour edge, which suggests that tumour-released angiogenic factors are only effective over a short distance.     

血小板激活因子对大鼠脑血管通透性的影响及药物的保护作用

颈内动脉注射血小板激活因子(PAF),再给伊文思蓝,可见脑实质染色程度加深,而颈内动脉只注射伊文思蓝,脑实质未见染色。而我们合成的新药SZ-1可剂量依赖性地抑制PAF诱导的脑实质伊文思蓝染色程度的加深。在体外培养的脑微血管平滑肌细胞上,PAF能显著刺激¹⁴C-花生四烯酸的释放,而SZ-1能剂量依赖性地抑制这种释放,提示PAF在脑内产生的损害除与其他因素相关外,还与其刺激花生四烯酸释放有密切关系,SZ-1对PAF引起的脑部损害有保护作用。     

Television viewing time and weight gain in colorectal cancer survivors: a prospective population-based study

Objective  

To investigate the prospective relationships between television viewing time and weight gain in the 3 years following colorectal cancer diagnosis for 1,867 colorectal cancer survivors (body mass index (BMI) ≥ 18.5 kg/m²).