骨组织工程种子细胞的研究进展

随着骨组织工程研究的进展 ,选择什么细胞作为其种子细胞成为近年来研究的热点。目前 ,骨组织工程应用中种子细胞有五种来源 :骨、骨膜、骨髓、骨外组织和早期胚胎。本文介绍了五种来源种子细胞的研究状况 ,并对种子细胞各自存在的问题及应用前景进行了分析。     

Detection and delineation of an unusual 17p11.2 deletion by array-CGH and refinement of the Smith–Magenis syndrome minimum deletion to 650 kb

Smith–Magenis syndrome (SMS) is a multiple congenital anomaly/mental retardation syndrome and it is characterized by an interstitial deletion of chromosome 17p11.2. SMS patients have a distinct phenotype which is believed to be caused by haploinsufficiency of one or more genes in the associated deleted region. Five non-deletion patients with classical phenotypic features of SMS have been reported with mutations in the retinoic acid induced 1 (RAI1) gene, located within the SMS critical interval. Happloinsufficiency of the RAI1 gene is likely to be the responsible gene for the majority of the SMS features, but other deleted genes in the SMS region may modify the overall phenotype in the patients with 17p11.2 deletions. SMS is usually diagnosed in the clinical genetic setting by FISH analysis using commercially available probes. We detected a submicroscopic deletion in 17p11.2 using array-CGH with a resolution of approximately 1 Mb in a patient with the SMS phenotype, who was not deleted for the commercially available SMS microdeletion FISH probe. Delineation of the deletion was performed using a 32K tiling BAC-array, containing 32,500 BAC clones. The deletion in this patient was size mapped to 2.7 Mb and covered the RAI1 gene. This case enabled the refinement of the SMS minimum deletion to 650 kb containing eight putative genes and one predicted gene. In addition, it demonstrates the importance to investigate deletion of RAI1 in SMS patients.     

High protein intake accelerates the maturation of Na,K-ATPase in rat renal tubules

We have examined the effect of a high protein intake on renal maturation by studying the Na,K-ATPase activity in proximal convoluted tubules (PCT) and medullary thick ascending limb of Henle (TAL) in kidneys from 16- to 24-day-old rats. The rats received an isocaloric diet containing 21% (normal protein, NP) and 50% (high protein, HP) protein from 16 days of age. HP diet significantly increased the nephron filtration rate after 2 days. There was a proportionate increase in proximal tubular reabsorption. HP diet significantly increased Na,K-ATPase in both PCT and TAL after 4 days, but not after 2 days. Although HP diet caused a similar increase in Na delivery to PCT and TAL, the increase in Na,K-ATPase activity after 8 days was more pronounced in TAL than in PCT. To determine whether stimulation of Na,K-ATPase required the presence of adrenal corticoid hormones, rats adrenalectomized at 16 days of age were studied. HP diet significantly increased Na,K-ATPase in both PCT and TAL from adrenalectomized rats. To determine whether stimulation of Na,K-ATPase in PCT was mediated by increased Na entry via the amiloride-sensitive Na/H exchanger, rats were treated with amiloride via an osmotic minipump from 16 to 20 days of age. Amiloride treatment significantly retarded the normal increase of Na,K-ATPase in NP rats but had no effect on ouabain-insensitive ATPase. HP diet significantly increased PCT Na,K-ATPase, in spite of chronic amiloride treatment. Conclusion: HP intake accelerates maturation of Na,K-ATPase in PCT and TAL regardless of the presence of adrenal corticoid hormone.(ABSTRACT TRUNCATED AT 250 WORDS)     

Induction of β-family chemokines mRNA in human embryonic astrocytes by inflammatory cytokines

The cellular infiltration found during CNS inflammation consists of monocytes and activated T cells, suggesting the presence of cell-specific chemotactic signals during inflammatory responses. Astrocyte chemokine expression might contribute to site-specific leukocyte infiltration within the CNS. To investigate the factors that regulate astrocyte chemokine expression, we examined the ability of human fetal astrocytes to induce -family chemokine mRNA. Astrocyte-derived monocyte chemoattractant protein-1 (MCP-1), RANTES, macrophage inflammatory protein-1 (MIP-1), and MIP-1 mRNA were easily induced by lipopolysaccharide and/or the proinflammatory cytokines (IFN and/or TNF-), respectively. Addition of both IFN and TNF- together did not lead to an additive effect but resulted in the inhibition of MCP-1 and MIP-1 mRNA expression, indicating that interaction between chemokines and cytokines may play a key role in regulating the local immune response of resident and infiltrating cells at the site of lesion. Interestingly, ultraviolet light-inactivated measles virus, but not cytomegalovirus, strongly induced expression of MCP-1, RANTES, MIP-1, and MIP-1 mRNA in human embryonic astrocytes, especially MCP-1 and MIP-1. An association occurs between the -family chemokine expression in astrocytes and inflammatory factors/virus, suggesting a possible role for -family chemokines in the pathogenesis of CNS inflammatory disease.     

Behavioural effects of human fetal dopamine neurons grafted in a rat model of Parkinson's disease

Summary The ventral mesencephalon, containing the developing dopaminergic neurons of the substantia nigra-ventral tegmental region, was obtained from aborted human fetuses of 9–19 weeks of gestation. The tissue was grafted into the striatum of rats previously subjected to a 6-hydroxydopamine lesion of the mesostriatal dopamine pathway. The graft recipients were immunosuppressed by daily injections of Cyclosporin A. Amphetamine-induced motor asymmetry was reduced, and finally totally reversed, only in rats receiving grafts from the 9-week old fetal donor. The fluorescence microscopic analysis revealed large numbers of surviving dopamine neurons, and extensive fiber outgrowth into the host striatum, in these rats. By contrast, rats receiving grafts from 11–19 week old donors had at most only few surviving dopamine neurons. These results indicate that human fetal mesencephalic tissue may be an efficient source of dopamine neurons for functional intracerebral grafting in patients with Parkinson's disease.A preliminary account of some of the results from this study was presented at the New York Academy of Sciences meeting on Cell and tissue transplantation into the adult brain, New York, April 4, 1986     

Prognostic evaluation before operative extirpation and radiotherapy of solitary brain metastasis

Summary This is a retrospective study of 134 patients operated on for solitary brain metastasis at the University Hospital in Uppsala, Sweden between 1963 and 1982. All the patients underwent postoperative radiation therapy. A statistical evaluation of different prognostic factors was made in order to create a prognostic model, a so-called risk profile, to be used for future patients. The most important factors for the making of risk profiles were found to be the histological diagnosis followed by the location in the brain, then the state on admission and the age at admission in that declining order. All these variables separately and together,i.e., as risk profiles, were matched against the outcome during survival as Karnofsky's scores and against the length of survival time. The results are shown in a diagram giving the surgeon grounds for his decision-making for or against operation and also for pre-operative information.     

双歧杆菌QJ 405和乳酸杆菌QJ 405的生物学特征及鉴定

目的：观察从健康核潜艇艇员正常粪便中分离出的双歧杆菌QJ405和乳酸杆菌QJ405的生物学特征,判定其是否符合益生菌要求。方法：分析细菌的形态学和生理生化特征。采用数值分类法（API20A）的化学分类法（气相色谱分析）进行种属鉴定。抗生素敏感试验采用ATB法。结果：两株菌分别鉴定为长双杆菌和唾液乳酸杆菌唾液亚种,两菌代谢发酵碳水化合物均可产生大量乙酸、乳酸,对多种抗生素表现敏感。结论：双歧杆菌QJ405和乳酸杆菌QJ405的来源和部分生物活性符合益生菌的要求。     

上海市长宁区中老年妇女慢性病现况调查

目的 了解中老年女慢性病患病状况,为社区中老年妇女的疾病预防、健康促进及制定中老年卫生政策提供科学依据。方法 采用入户调查的方式,对上海市长宁区75368名40－69岁中老年妇女常见慢性病患病率及常见关联因素,进行了结构式问卷调查。结果 在长宁区中老年妇女中,各种常见慢性病患病率居前5位的依次为高血压（23．9％）、慢性胃炎（19．7％）、冠心病（7．4％）、肿瘤（6．5％）和糖尿病（4．4％）。常见恶性肿瘤中,乳腺癌患病率最高（750／10万）,其次是胃癌（130／10万）。影响慢性病患病率的因素包括年龄、婚姻状况、吸烟、饮酒及饮茶等。结论 社区卫生工作应从健康教育入手,积极开展老年病防治工作。卫生部门应关注人口老龄化带来的新问题,积极提高中老年妇女的健康状况。