Murine type C endogenous virus expression in murine 129 teratocarcinoma cell line]

Murine type C viral information is detectable in the cellular genome of both differentiated and undifferentiated cell lines derived from 129 Mouse teratocarcinoma. Cytoplasmic RNA expression which is negligible in differentiated cells, is significantly higher in multipotential undifferentiated cells. Furthermore it was observed that in vitro differentiation of multipotent cells leads to a decrease of this expression.     

Compared expression of murine plasmacytoma associated virus in tumor cells and in mouse embryo cells]

A DNA complementary to the viral genome of C-type particles produced by a Mouse myeloma derived cell line (MF2 cell line) was synthesized. This cDNA was used as a probe to study the viral genome expression among the total RNA and the poly (A)-rich RNA extracted from the MF2 and Balb/c embryonic cells. As evidenced by molecular hybridization experiments, the presence of at least one endogenous Balb/c virus in the MF2 virus stocks is suggested. In the productive cells, the viral RNA sequences are expressed in the poly (A)-rich RNA fraction.     

Action of Corynebacterium parvum on the activity of glycosidases and proteases of peritoneal macrophages in the mice]

Glycosidase and peptidase of non-treated Mouse peritoneal macrophages were characterized. The enzymatic activities of Corynebacterium parvum stimulated Mouse macrophages were compared to those of macrophages obtained from non-treated animals. All the enzymatic activities, but beta-C-galactosidase, were higher in stimulated Mouse macrophages.     

The existence in Europe of four groups of mice (genus Mus L.) of species and subspecies rank, demonstrated by biochemical genetics]

Analysis at 20 genetic loci by starch gel electrophoresis of a population from Greece shows that contrary to most accepted views, the outdoor Eastern Mediterranean Short-tailed Mouse (i) does not belong to the same species as the House Mouse (Mus musculus), (ii) is not less distant from the Eastern European semi-species of House Mouse (biochemical group 2) than from the Western and Mediterranean European semi-species (group 1), and (iii) is not more closely related to the outdoor Western Mediterranean Short-tailed Mouse Mus spretus (group 3), than to M. musculus. It represents a new biochemical group (group 4) and deserves a species rank (Mus spicilegus).     

2,4-dinitro-(pyrimidine-2-yl) thiophenol, a new drug with antimitotic properties]

A new thiopyrimidine derivative has been synthesized. It can inhibit cell multiplication in Chick embryo fibroblasts, in Mouse Ehrlich ascites tumor cells and in Rat hepatoma cells (line Rueber) cultivated in vitro.     

Attempt at activating mouse intracisternal type A particles by iododeoxyuridine and dexamethasone]

In this study we have compared the effects of Iododeoxyridine (IUdR) and dexamethasone on different Mouse cell lines to determine any differences in their actions on intracisternal A-type particles (IAP). Among the nine cell lines studied only four responded to IUdR stimulation by a subsequent augmentation of IAP. No similar activating effect was detected with dexamethasome treatment.     

Different sensitivities to ultraviolet rays of various functions of the polyoma virus. Stimulation of the synthesis of cellular DNA]

Peritoneal Mouse macrophage were used to study the stimulation of cell DNA synthesis by polyoma virus. Using ultraviolet-irradiated polyoma virus, it was possible to show a difference between the inactivations of infectivity and of induction of DNA synthesis. By statistically analysis of these two phenomena it was found that 39% of the viral genome is necessary for the induction of cell DNA synthesis.     

Expression of an antigen associated with Gross virus on the surfaces of murine cells producing an oncornavirus from the radioleukemia of C57BL/6 mice]

A leukemogenic viral complex was demonstrated in cultures of 13-3 C cell line derived from a C57BL/6, radiation leukemia virus (RadLV-Rs) induced tumor. Both 13-3C and leukemic cells induced in C57BL/6 mice by 13-3C virus carry a cell surface antigen associated with Gross leukemia virus (GCSAa). These findings point to a close similarity between these antigens and those of murine endogenous ecotropic viruses.     

Replication pattern of double minutes derived from an insect cell line

The DNA replication pattern of double minutes derived from an established cell line of Aedes albopictus is described. Although the vast majority of double minutes replicate semiconservatively once during the S phase, some double minutes appear to exhibit different pattern(s). Two theories are suggested as possible explanations of our findings.     

Cell transformation in vitro by transfer of isolated metaphase chromosomes]

Human and murine cells can be transformed in vitro following transfer of chromosomes (transfection) isolated from tumour (HeLa) or SV40-transformed (WI98VaD) human cells. An abortive transformation of Mouse cells is observed in soft-agar medium. An instability of the transformed phenotype is exhibited by the transfected human cells, following the isolation of colonies growing in soft-agar or low-serum medium. Nevertheless, two transformed cell lines (809 ch. VaD, Cl.5P and Cl.6P) could be established in culture.     

Detection of human antigens on the surface of mouse cells transformed by chromosome transfer]

Mouse embryo cells, transformed in vitro by the transfer of chromosomes from HeLa human tumour cells, express a surface antigen (s) also found on HeLa cells. This antigen(s), which has been detected both by indirect immunofluoresence and by a 125I-protein A binding assay, is not an antigen(s) shared by both Human and Mouse cells.     

Replication pattern of double minutes derived from an insect cell line

Summary The DNA replication pattern of double minutes derived from an established cell line ofAedes albopictus is described. Although the vast majority of double minutes replicate semiconservatively once during the S phase, some double minutes appear to exhibit different pattern(s). Two theories are suggested as possible explanations of our findings.This work was supported by a grant from the Whitehall Foundation, Inc. awarded to A.B.M.     

The influence of MuLV and SV40 viruses on senescence in mouse fibroblasts in vitro

Summary Mouse cells productively infected with Moloney leukaemia virus (MuLV) underwent senescence in a manner similar to control cells, although they recovered more readily as an established line. Rapidly growing cell lines were also obtained following simian virus 40 (SV40) infection of senescent cells. However, superinfection of senescent MuLV-producing cells by SV40 led to slower growing cells with a reduced output of infectious MuLV.     

The influence of MuLV and SV40 viruses on senescence in mouse fibroblasts in vitro.

Mouse cells productively infected with Moloney leukaemia virus (MuLV) underwent senescence in a manner similar to control cells, although they recovered more readily as an established line. Rapidly growing cell lines were also obtained following simian virus 40 (SV40) infection of senescent cells. However, superinfection of senescent MuLV-producing cells by SV40 led to slower growing cells with a reduced output of infectious MuLV.     

基于DSP＋FPGA的数字电视条件接收系统设计

采用DSP＋FPGA结构实现数字电视条件接收系统的硬件设计；以安全性高、密钥量小、灵活性好的椭圆曲线密码算法（ECC）进行软件验证；以DSP实现ECC加密算法；以FPGA实现外围电路的嵌入式系统；充分利用FPGA的硬件连接方式和DSP强大的运算，采用软硬结合的方式，实现数字电视条件接收系统的设计，减少系统开发的时间与成本。仿真及实验表明：该算法稳定运行，并快于其它公钥密码算法。     

Loss of steroidogenesis in a mouse adrenal cell line after simian adenovirus 7 (SA7) transformation]

After transformation by the simian adenovirus 7 (SA7), the Y-1 Mouse adrenal tumor cells are no longer able to produce stero?ds either spontaneously, or after specific stimulation. Nevertheless, these stimulations are able to increase the level of cAMP both in transformed and original cell line. The differentiation is associated with an intracellular modification of stero?dogenesis which seems to be localized in the metabolic chain of stero?d synthesis after the increase of the cAMP level.     

染料敏化电池-温差热电混合发电系统的性能研究

建立染料敏化电池一温差热电混合发电系统的理论模型,利用非平衡态热力学理论导出该混合发电系统输出功率和效率的一般表达式,分析系统的一般性能特性,确定混合发电系统在最大输出功率和效率时的优化条件,讨论了一些主要性能参数对混合发电系统性能特性的影响．结果表明使用半导体温差热电器可有效地利用染料敏化电池所产生的低品位的废热,从而提高混合发电系统整体的输出功率和效率．本文所得结果可为实际混合发电器的设计和优化运行提供理论依据．     

Analysis of OCT4 expression in an extended panel of human tumor cell lines from multiple entities and in human mesenchymal stem cells

OCT4 is considered a main regulator of embryonic stem cell pluripotency and self renewal capacity. It was shown that relevant OCT4 expression only occurs in cells of embryonic pluripotent nature. However, several recent publications claimed to have demonstrated OCT4 expression in human somatic tumor cells, human adult stem or progenitor cells and differentiated cells.We analysed 42 human tumor cell lines from 13 entities and human bone marrowderived mesenchymal stem cells (MSC). To validate OCT4 expression we used germ cell tumor (GCT) cell lines, derived xenografts and GCT samples. Analysis by RT-PCR, western blotting, immunocytochemistry and immunohistochemistry was performed. With exception of typical embryonal carcinoma cells, we did not observe reliable OCT4 expression in somatic tumor cell lines and MSC. We suggest that a high level of expression of the OCT4 protein together with its nuclear localization still remains a reliable and definitive feature of cells with embryonic pluripotent nature. Received 30 September 2008; received after revision 05 November 2008; accepted 10 November 2008     

Purification and characterization of bovine pancreatic alpha-amylase

A method for the purification of alpha-amylase from Bovine pancreas homogenate is described. This enzyme has the same molecular weight as the Porcine isoenzymes but its isoelectric point is more basic. Its amino acid composition is similar to that of Porcine, Ovine, Rat and Mouse amylases.