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941.
Nishikawa Y Iwata A Katsumata A Xuan X Nagasawa H Igarashi I Fujisaki K Otsuka H Mikami T 《Virus research》2001,75(2):113-121
A recombinant vaccinia virus-expressing canine interferon (IFN)-gamma (vv/cIFN-gamma) was constructed. In rabbit kidney (RK13) and canine A72 cells infected with vv/cIFN-gamma, IFN activity was detected in the culture supernatants of both cell types. Canine IFN-gamma was also detected in both cell extracts by Western blot. The activity of the recombinant canine IFN-gamma in RK13 cells was higher than that in A72 cells. The vv/cIFN-gamma could not grow in A72 cells at a low multiplicity of infection, probably due to the antiviral activity of the canine IFN-gamma produced. Although exogenous IFN-gamma did not inhibit the growth of vaccinia virus, addition of anti-canine IFN-gamma serum recovered the growth of the vv/cIFN-gamma on A72 cells in a dose-dependent manner. These results suggest that the growth of vv/cIFN-gamma was inhibited by IFN-gamma produced in a paracrine and autocrine manner. In addition, the recombinant canine IFN-gamma inhibited the multiplication of canine herpesvirus, pseudorabies virus and canine adenovirus type 1 in Madin-Darby canine kidney cells. The antiviral effect of canine IFN-gamma was more effective than that of canine IFN-beta. From the present studies, we concluded the recombinant virus may be a useful suicide viral vector. 相似文献
942.
The aim of the present study is to demonstrate the cellular basis of 5'-nucleotidase (5'-Nase) activity in the greater omentum of rats. Enzyme histochemistry for 5'-Nase showed that lymphatic vessels in the omentum as well as lymphocytes in the milky spots were positively stained. Electron microscopic observation revealed-5'-Nase activity at the luminal surface of the lymphatic endothelial cells, pinocytotic vesicles in the endothelial cells and the surface of fibroblasts located at the intercellular space of adipose cells. Fibroblasts extended long cytoplasmic processes toward adipose cells and inflammatory cells. These findings suggest that lymphatic endothelial cells as well as fibroblasts in the omentum may play an important role in regulation of metabolism and immune mechanisms in the greater omentum by supplying adenosin. 相似文献
943.
Metabotropic glutamate receptors have a variety of effects in visual cortex that depend on the age of the animal, the layer of the cortex, and the group of the receptor. Here we describe these effects for group I receptors, using both in vivo and in vitro preparations. The metabotropic group I glutamate receptor agonist 3,5 dihydroxyphenylglycine (DHPG) potentiates the responses to N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) in slices of rat visual cortex. It also increases, initially, the visual response in the cat visual cortex. Both these effects are largest at 3-4 wk of age and decline to insignificance by 10 wk of age. Both are also largest in lower layers of cortex, which explains why the facilitatory effects found with the general metabotropic glutamate agonist 1S,3R aminocyclopentane-1,3-dicarboxylic acid (ACPD) are observed only in lower layers. Prolonged application of DHPG in the cat visual cortex, after the initial excitatory effect, produces depression. We also found that DHPG facilitates the NMDA response in fast-spiking cells, which are inhibitory, providing a partial explanation for this. Thus there are multiple effects of group I metabotropic glutamate receptors, which vary with layer and age in visual cortex. 相似文献
944.
Analytical methodology for enantiomers of salbutamol in human urine for application in doping control 总被引:2,自引:0,他引:2
Bergés R Segura J de la Torre X Ventura R 《Journal of chromatography. B, Biomedical sciences and applications》1999,723(1-2):173-184
Liquid chromatographic procedure with fluorimetric detection for chiral separation and quantification of salbutamol enantiomers in urine samples has been developed. The extraction of free salbutamol from urine has been considered using liquid-liquid and solid-phase procedures. The effect of pH, salting-out effect and organic solvent has been studied in liquid-liquid extraction from aqueous and urine samples. For solid-phase extraction, different mechanisms (polar, non-polar, cation-exchange and interactions with a polymeric phase) have been tested and the effect of the urine matrix on the extraction recoveries has been considered. Bond-Elut Certify extraction cartridges provided the best specificity and good recoveries for salbutamol in urine. The sample is acidified, applied to the preconditioned cartridges and, after a washing step, salbutamol enantiomers are eluted with a mixture of chloroform and 2-propanol (80:20, v/v) containing 2% ammonia. Atenolol is used as external standard. Enantioselective separation is accomplished with a Chirex 3022 stationary phase (urea type silica-bonded chiral phase) using a mobile phase containing hexane-dichloromethane-methanol-trifluoroacetic acid (250:218:31:1, v/v) and fluorimetric detection with excitation and emission wavelengths set at 230 and 309 nm, respectively. The method proposed is rapid, selective and sensitive, and seems to be useful to differentiate between an authorized and a prohibited use of the drug in doping control. 相似文献
945.
Zhu P Liu X Luo H Gu Z Cheng J Xu R Lian S Wu S Wang J 《Human reproduction (Oxford, England)》1999,14(4):970-975
Thirty-four women bearing a levonorgestrel-releasing intrauterine device, 20 micrograms/day (LNG-IUD-20), for 12-15 months were recruited. Endometrial biopsies were collected during the late proliferative phase of the cycle (on cycle days 10-12) before (control) and after the use of the IUD for 12 months, and assayed for oestrogen receptors (ER) and progesterone receptors (PR). An immunohistochemical technique with the peroxidase-antiperoxidase detection system (PAP method) was employed. D75 and JZB39 were the primary antibodies for ER and PR respectively. The immunostaining semiquantitative analysis was performed with a computerized microscope image processor, and expressed as 'grey value'. Both endometrial ER and PR populations were significantly lower after insertion of the IUD (P < 0.01) than in control biopsies. The intensity of nuclear staining and the percentage of positively stained cells for ER and PR in women with LNG-IUD were each about 50% of those in control biopsies. The results suggested that LNG released locally from the IUD has a depressive action on the ER and PR, which may contribute to the contraceptive effectiveness of this type of IUD and also to the possible causes of LNG-IUD-induced irregular bleeding and amenorrhoea. 相似文献
946.
It has been suggested that immune responses are involved in the development of atherosclerosis. We have evaluated this possibility by analyzing immunocompetent cells in a murine model of the disease. Apolipoprotein E knockout (apoE -/-) mice are genetically hypercholesterolemic due to targeted disruption of the apolipoprotein E gene and develop severe atherosclerosis. Such mice were fed either standard pellets or a diet containing 1.25% cholesterol. Lesions were analyzed from mice at 9 and 16 weeks of age. Immunohistochemical staining of fatty streaks showed that CD4+ T cells were frequent, both in clusters and as single cells. In advanced atherosclerotic plaques, CD4+ T cells were prominent in the fibrous cap and subendotbelially, whereas CD8+ T cells were sparse. The CD25 subunit of the interleukin-2 receptor, which is a marker for activated T cells, was expressed in CD4-rich areas and the major histocompatibility complex class II antigen, I-A(b), which is induced by cytokines released from activated T cells, was also found in the lesions. These data indicate that CD4+ T cells participate in the formation of atherosclerotic lesions in genetically hypercholesterolemic apoE -/- mice. They suggest that immune activation is part of the disease process, and we speculate that a direct link may exist between cholesterol accumulation and T cell activation, possibly by autoimmune responses to modified lipoproteins. 相似文献
947.
Identification of testis development and spermatogenesis-related genes in human and mouse testes using cDNA arrays 总被引:12,自引:0,他引:12
Sha J Zhou Z Li J Yin L Yang H Hu G Luo M Chan HC Zhou K;Spermatogenesis study group 《Molecular human reproduction》2002,8(6):511-517
We have constructed cDNA microarrays from the human testis large insert cDNA library, containing 9216 genes, together with several housekeeping genes. The cDNA microarrays were used to identify gene expression differences between human fetal and adult testes. Of >8700 hybridized clones, 731 exhibited significant differential expression characteristics. About 7500 genes were identified when the same cDNA microarrays were used for hybridization with cDNA probes from mouse testis, with 256 genes having significant differential expression between the age of 1-4 weeks. Among these genes, 101 were identified as critically related to testis development and possibly to spermatogenesis since they were found in both human and mouse testes, and expressed differentially at different stages of testis development. Of the 101 development-related genes, 59 full-length cDNAs have been sequenced previously, while the full-length cDNAs of the other 42 genes have not been published. We have obtained 11 full-length sequences of the 42 genes and deposited them in the GenBank. The conserved testis development-related genes found in both human and mouse testes may include genes that are likely to be involved in testicular functions, especially spermatogenesis, thus providing a basis for further functional characterization of the genes in mouse models. 相似文献
948.
目的构建鸡胚背根节细胞3D生长模型,观察CSPG对不同浓度的琼脂糖水溶胶培养基对鸡胚背根节神经突起生长的影响。方法①利用多肽缩合剂1’1羰基二咪唑介导CS-B长链与琼脂糖凝胶共价结合。②分别配制0.5%、0.75%、1%、1.25%、1.5%的SeaPrep琼脂糖凝胶溶液和共价结合了CS-B多糖长链的琼脂糖凝胶溶液。取孵育9~10天后鸡胚背根节加入上述凝胶溶液加培养液培养。③培养24小时之后在24 h、48 h7、2 h、96 h进行观察拍照。观察各时间点神经突起生长情况。结果①鸡胚背根节神经突起在1.25%的琼脂糖凝胶溶液中开始呈3D生长,在小于1%的琼脂糖溶液中只能2D生长。②在同一时间点,呈2D生长的背根节突起和呈3D生长的背根节突起在突起长度方面没有统计学差异(P>0.05)。③3D生长的DRG神经突起在共价结合了CS-B的琼脂糖凝胶中生长长度明显短于普通琼脂糖水凝胶(P<0.05),并且可观察到部分突起长出短而直的成束突起。但是对于呈2D生长的DRG突起长度在两种培养基中却未见差异(P>0.05)。结论鸡胚背根节神经元周围突起生长长度在3D培养中与在2D培养中有没有明显的差异。硫酸软骨素能够有效抑制呈3D生长的神经节突起生长,并且影响到神经突起的生长方式。但是在2D培养基中,未能看到上述的抑制作用。 相似文献
949.
950.
PCR based mutation screening of the laminin alpha2 chain gene (LAMA2): application to prenatal diagnosis and search for founder effects in congenital muscular dystrophy. 总被引:1,自引:0,他引:1 下载免费PDF全文
P Guicheney N Vignier X Zhang Y He C Cruaud V Frey A Helbling-Leclerc P Richard B Estournet L Merlini H Topaloglu M Mora J P Harpey C A Haenggeli A Barois B Hainque K Schwartz F M Tomé M Fardeau K Tryggvason 《Journal of medical genetics》1998,35(3):211-217
Classical congenital muscular dystrophy with merosin deficiency is caused by mutations in the laminin alpha2 chain gene (LAMA2). Extended sequencing of the introns flanking the 64 LAMA2 exons was carried out and, based on these sequences, oligonucleotide primers were designed to amplify the coding region of each exon separately. By PCR-SSCP analysis, we identified eight new mutations in nine families originating from various countries. All induced a premature truncation of the protein, either in the short arm or in the globular C-terminal domain. A 2 bp deletion in exon 13, 2098delAG, was found in three French non-consanguineous families and a nonsense mutation of exon 20, Cys967stop, in two other non-consanguineous families originating from Italy. Determination of rare intragenic polymorphisms permitted us to show evidence of founder effects for these two mutations suggesting a remote degree of consanguinity between the families. Other, more frequent polymorphisms, G to A 1905 (exon 12), A to G 2848 (exon 19), A to G 5551 (exon 37), and G to A 6286 (exon 42), were used as intragenic markers for prenatal diagnosis. This study provides valuable methods for determining the molecular defects in LAMA2 causing merosin deficient congenital muscular dystrophy. 相似文献