Characteristics of human neural stem cells In Vitro and after transplantation into rat brain

We studied the effect of culturing conditions on the fate of human neural stem cells after transplantation into rat brain. Human neural stem cells cultured in the presence of mitogens without LIF migrated along the ependyma and cerebral vessels of recipients, but to a great extent degenerated by the 20th day after transplantation. Neural stem cells cultured with LIF migrated, apart from the above mentioned pathways, in the cortex and hippocampus, well survived; proliferating cells were retained 30 days after transplantation.__________This revised version was published online in July 2005 with the addition of the issue title and article categoryTranslated from Kletochnye Tekhnologii v Biologii i Meditsine, Vol. 1, No. 1, pp. 13–19, January, 2005     

Expression of superoxide dismutase and xanthine oxidase in myometrium, fetal membranes and placenta during normal human pregnancy and parturition

Superoxide, an agent which attenuates the half-life of nitric oxide, is metabolized and synthesized by superoxide dismutase (SOD) and xanthine oxidase, respectively. Over the last few years much work has focused on the role of nitric oxide in human parturition. The aim of this study was to determine whether the onset of human parturition is associated with a change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD), manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the uterus. Samples of myometrium, placenta, decidua and fetal membranes were obtained from women before and after the onset of labour at term. Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like immunoreactivity was detected in syncytiotrophoblast cells, villous stromal cells and endothelial cells of blood vessels in the placenta. In the myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial cells and to some vascular smooth muscle cells. In the fetal membranes we observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion, extravillous trophoblast and decidua. There was no difference in SOD enzyme activity or staining intensity for SOD between different cell types before and during labour. Xanthine oxidase immunoreactivity was identified in each of the tissues examined and again there was no difference in immunostaining in tissues obtained from women delivered before or after the onset of labour. These results show that the pregnant uterus is capable of both synthesizing and degrading superoxide and suggest that superoxide dismutase and xanthine oxidase may play a role in the maintenance of uterine quiescence during pregnancy, but not in the initiation of parturition.      

The nitric oxide pathway in pre-eclampsia: pathophysiological implications

Pre-eclampsia, one of the most significant health problems inhuman pregnancy, complicates 6-7% of all gestations and is theleading cause of fetal growth retardation, infant morbidityand mortality, premature birth and maternal death. Recent researchimplicates free radicals in the pathophysiology of pre-eclampsia.This review covers the biochemistry of nitric oxide (NO) andpossible interactions with other free radicals. Studies in therat show that pregnancy is associated with enhanced productionand responsiveness to NO in both reproductive tissues and bloodvessels. Rats infused with N^G-nitro-L-arginine methyl ester(L-NAME, a NO synthase inhibitor) have been used as an animalmodel of pre-eclampsia, and the effects of steroid hormoneson blood pressure in this model have been tested. Results suggestthat pre-eclampsia may be a state of NO deficiency. However,in humans there seem to be contradictions regarding the involvementof NO in maternal adaptation to pregnancy. It is suggested thatNO may be one of several systems that act in concert to maintaina symbiotic relationship between mother and fetus. However,the input of each system may be genetically determined.     

Mutations in the genes coding for hemagglutinin and neuraminidase in cold-adapted variants of the influenza virus A/Leningrad/134/57 (H2N2)

An analysis of ts-mutations in the genomes of native and cold-adapted variants of influenza A/Leningrad/134/57 (H2N2) virus based on the use of fowl plague virus ts mutants was carried out. The recombination test was done by the conventional method in chick embryo fibroblast culture (genes PB2, PB1, PA, NP, NA, M and NS) or cell systems permissive for reproduction of human influenza virus (gene HA). The cold-adapted strain A/Len/17 used for preparation of live influenza vaccine (LIV) for adults was shown to have 4 ts mutations: three in "internal" genes (PB2, NP, and M) and one in gene 4 coding for hemagglutinin (HA). The more attenuated cold-adapted donor A/Len/47 for preparation of similar LIV for children acquired three additional ts mutations: two (PB1 and NS) in "internal" genes and one in gene 6 coding for neuraminidase (NA). The accumulation of ts mutations in the genome of cold-adapter strains was found to be accompanied by a decrease in their pneumotropicity for mice as well as their detectability in different organs of these animals.     

Identification of MEN1 gene mutations in sporadic carcinoid tumors of the lung

Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors.      

Thrombo ASS in the prophylaxis of vascular disorders in antiphospholipid syndrome

The aim of the study was to try thrombo ASS in combined therapy of patients with antiphospholipid syndrome (APS), to evaluate its efficacy in prevention of recurrent vascular defects. Thrombo ASS tablets (50-100 mg) were included in combined treatment of 45 patients with APS (6 males and 39 females, mean age 36.1 +/- 11.7 years, mean APS duration 10.2 +/- 9.0 years) and 8 patients with SLE (1 male and 7 females) matched for age. Antiphospholipin antibodies and clinical status were assessed before treatment and after the treatment within 9 months. It was found that addition of thrombo ASS to combined treatment of APS improves coagulation and microcirculation due to effective muscular blood flow, increases number of platelets in peripheral blood. Tablets covered with coating resistant to gastric juice reduce frequency of gastric side effects.     

散发内淋巴囊瘤VHL基因位点微卫星标志杂合性丢失的研究

目的 探讨散发内淋巴囊瘤发病与VHL基因异常之间的关系。方法 采用组织微切割技术和多聚酶链式反应等方法对3例散发内淋巴囊瘤肿瘤细胞VHL基因位点染色体微卫星标志的杂合性丢失进行分析。结果 3例散发内淋巴囊瘤中有2例发生VHL基因位点微卫星标志的杂合性丢失,进一步的研究证实,该两例肿瘤细胞中分别存在着VHL基因第二外显子的异常。结论 VHL基因的异常导致其功能改变不但是VHL的致病原因,而且是散发性内淋巴囊瘤发病的重要的基因遗传学基础。