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941.
The objective of the study was to provide immunization policy decision makers with a risk-benefit analysis for pre-adolescents vaccination, for various scenarios regarding the existence and the strength of an association between hepatitis B vaccination and the occurrence of first episode of central demyelinating (FECD) disease. The risks were assessed as the attributable risks of FECD for various time intervals between vaccination and onset of FECD and the benefits as the number of acute fulminant hepatitis B and cirrhosis prevented in a vaccinated annual cohort. Even in the worst-case considered, the number of complications prevented by the vaccination outweighs quantitatively the potential risks. Even if both sides of the balance are of different medical and sociological nature, this result is in favor of reinforcing the pre-adolescent vaccination strategy in France. 相似文献
942.
943.
Bertrand Jacques Jean-Claude Amir Mustafa Z. Damian Josie De Marte Daniela Eliza Vasilescu Rose Yen Thak Hak Chan Brian Leyland-Jones 《Cancer chemotherapy and pharmacology》1998,42(1):59-67
Cytotoxicity, reduction of macromolecule synthesis and cell cycle perturbations by two novel 3-(2-chloroethyl)-tetrazepinones,
PYRCL and QUINCL were compared with those produced by the structurally related 3-(2-chloroethyl)-tetrazinone, mitozolomide,
in the OVCAR-3 cell line. Methods: Macromolecule synthesis was determined by incorporation of 3H-thymidine, 3H-uridine and 3H-leucine into acid-precipitable fractions of OVCAR-3 cell extracts. Maxam-Gilbert sequencing was used to compare the DNA
alkylating sites induced by the tetrazepinones, with those created by mitozolomide. Alkaline sucrose-density sedimentation
was employed to detect genomic DNA damage. Also, the effects of the tetrazepinones on the cell cycle were determined by univariate
flow cytometry. Results: At 3 h post-treatment, mitozolomide appeared as a selective inhibitor of DNA synthesis, while both tetrazepinones inhibited
the synthesis of all three macromolecules. At 24 h post-treatment, the inhibition of DNA synthesis was observed to increase
in cells treated with mitozolomide, while it decreased in those previously exposed to the tetrazepinones. Also at 24 h post-treatment,
mitozolomide induced accumulation of cells in S(late)/G2M at low concentrations and in S-middle at high concentrations. In contrast, at the same recovery time, cells treated with
the tetrazepinones accumulated specifically in G2M, the strength of the block being dose-dependent. At an equimolar concentration, the tetrazepinones induced weaker guanine
N-7 alkylation than mitozolomide. By 24 h after treatment, cells exposed to the tetrazepinones showed significantly greater
DNA fragmentation than those previously treated with mitozolomide. Conclusion: In summary, based on (a) their effects on DNA, RNA, protein synthesis and on the cell cycle, (b) their alkylating power
and (c) their interactions with DNA, the 3-(2-chloroethyl)tetrazepinones appeared to kill tumor cells by a novel mechanism
which may significantly differ from that of their 3-(2-chloroethyl)-tetrazinone counterpart, mitozolomide.
Received: 22 July 1997 / Accepted: 13 October 1997 相似文献
944.
Nathalie McIntosh David Chitayat Marietta Bardanis Jean-Claude Fouron 《American journal of medical genetics. Part A》1992,42(3):307-309
The Ebstein anomaly is a rare congenital heart disease involving the position and structure of the tricuspid valve. Although most cases are sporadic, familial occurrence has been documented. We report on 2 sisters, born to consanguineous parents, who were diagnosed prenatally with severe Ebstein anomaly. 相似文献
945.
Pierre Chatelain Patrick Robberecht Philippe De Neef Jean-Claude Camus Danielle Heuse Jean Christophe 《Pflügers Archiv : European journal of physiology》1981,389(1):29-35
Cardiac adenylate cyclase activity was normal in 3 weeks-old spontaneously hypertensive rats of the Wistar-Okamoto substrain. The hormone-sensitive adenylate cyclase activity was reduced in 10 weeks-old or older animals, and secretin- and VIP-activations were definitely more impaired (by 64% and 69%, respectively) than isoproterenol- and glucagonactivation (17% and 22%, respectively). By contrast, the fluoride- and p[NH]ppG-stimulations of the enzyme were unaffected. These alterations in the adenylate cyclase system coupled to secretin and VIP appeared specific to the heart as the isolated pancreatic acinar cells from spontaneously hypertensive animals responded normally to secretin, as a liver particulate fraction responded normally to secretin and VIP, and both brain synaptic membranes and a particulate fraction of anterior pituitary to VIP.Abbreviations VIP
vasoactive intestinal peptide
- cyclic AMP
cyclic adenosine 35-monophosphate
- p[NH]ppG
guanosine 5-(, -imido)triphosphate
- EGTA
ethylene-glycol-bis-(2-amino-ether)-N,N,N,N-tetraacetic acid
- IBMX
3-isobutyl-1-methylxanthine 相似文献
946.
Vautier D Karsten V Egles C Chluba J Schaaf P Voegel JC Ogier J 《Journal of biomaterials science. Polymer edition》2002,13(6):713-732
The aim of this study was to evaluate polyelectrolyte multilayer films as interfaces for implants. Polyelectrolyte multilayers were built up with different terminating layers by alternate deposition of oppositely charged polyelectrolytes on which chondrosarcoma (HCS-2/8) cells were grown in the presence of serum. Films formed by an increasing number of layers were investigated. The terminating layer was made of one of the following polyelectrolytes: poly-sodium-4-styrenesulfonate (PSS), poly-L-glutamic acid (PGA), poly-allylamine hydrochloride (PAH), or poly(L-lysine) (PLL). Cell viability, inflammatory response, adherence, and cytoskeletal organization were studied. Induction of interleukin-8 (IL-8) secretion was detected on PAH and PLL ending polyelectrolyte films. Early cellular adherence was enhanced with PGA, PAH, PLL, and, to a lower extent, PSS terminating layers. Adherence was independent of the number of layers constituting the films. The presence of actin filaments and vinculin focal adhesion spots was observed on PSS or PAH ending films. They were respectively partially and totally absent on PGA and PLL terminating multilayer architectures. For PLL ending films, vinculin and actin organization was clearly dependent on the number of deposited layers. The results of this study suggest that PSS ending multilayered films constitute a good interfacial micro-environment at the material surface for HCS-2/8 cells. 相似文献
947.
Development and validation of an immunoassay for identification of recent human immunodeficiency virus type 1 infections and its use on dried serum spots 总被引:1,自引:0,他引:1 下载免费PDF全文
Barin F Meyer L Lancar R Deveau C Gharib M Laporte A Desenclos JC Costagliola D 《Journal of clinical microbiology》2005,43(9):4441-4447
The objective was to develop and to validate an immunossay to identify recent human immunodeficiency virus type 1 (HIV-1) infections that can be used on dried serum spots (DSS). A single, indirect enzyme-linked immunosorbent assay was developed to quantify antibodies toward four HIV-1 antigens: consensus peptides of the immunodominant epitope of gp41 (IDE), consensus V3 peptides, recombinant integrase, and recombinant p24. The parameters of the logistic regression used to classify the samples were estimated on a training sample (210 serum samples) using resampling techniques to get stable estimates and then applied to a validation sample (761 serum samples). The IDE and V3 peptides were the best able to discriminate between the antibodies present in serum from recently (< or =6 months) infected individuals and those with long-lasting infection. Combined quantification of antibody binding to these two synthetic antigens allowed us to identify recent infections with an area under the receiver operating characteristic curve of 0.949 and a sensitivity of 88.3%, with a specificity of 97.6% in patients with long-term infection (but not AIDS) and 86.0% in patients suffering from AIDS with a threshold of 0.50 in the validation sample. This simple immunoassay can be used to identify recently HIV-1-infected patients. Its performance is compatible with its use in population-based studies including DSS. 相似文献
948.
Pierre Chatelain Patrick Robberecht Philippe De Neef Jean-Claude Camus Danielle Heuse Jean Christophe 《Pflügers Archiv : European journal of physiology》1980,388(1):29-35
The extrusion mechanism ofd-glucose by tubular cells was investigated in isolated rabbit kidneys perfused with normal or hyperglicemic blood, added with14C-inulin, by relating the values of the ratio between the intracellular and extracellular glucose concentration (Gi/Ge) in the cortical tissue to the respective plasma concentration Gp (=Ge). The apparent extracellular space was calculated in each experiment from the kinetics of the14C-inulin efflux from cortical slices excised at the end of the perfusion period (mean value = 20.7%±1.7 of the total vol.). The total intra and extracellular amount of glucose was measured in two contiguous slices excised from the cortex. The total water was expressed by the difference between the fresh and dry weight of the slice, the intracellular water by the difference between the total and extracellular water. From these volumes the respective apparent glucose concentrations could be found. The Gi/Ge values tend to 1, that is to a uniform intra and extracellular distribution of glucose, only at high plasma glucose levels. These results do not seem to be in agreement with ad-glucose transfer from the cell to the subepithelial spaces down a concentration gradient. 相似文献
949.
Jean-Claude Brosse Zainul Abdin Bin Maidunny Jean-Claude Soutif 《Macromolecular chemistry and physics.》1982,183(8):1959-1968
Squalene, as a model compound, and polyisoprene were metalated by the complex of sec-butyllithium (sec-BuLi) with N,N,N′,N′-tetramethylenediamine. The rate of metalation was determined indirectly by further reaction with a deactivating reagent. Amongst the various agents tested, a solution of chlorotrimethylsilane (Me3SiCl) in diethyl ether was preferred, as deactivation by this reagent does not lead to secondary reactions. The rate of silylation of sec-BuLi by Me3SiCl was found to be influenced by the solvent and the temperature. The presence of diethyl ether, as solvent of silylation, and a reaction temperature of 0°C are suitable conditions for the reaction between lithiated polymers and Me3SiCl. 相似文献
950.
Gupta-Rossi N Storck S Griebel PJ Reynaud CA Weill JC Dahan A 《Molecular immunology》2003,39(13):791-799
Ig gene hypermutation was originally described as the molecular process underlying B cell affinity maturation following a T-dependent immune response. Somatic hypermutation is also used in some species such as sheep, to generate diversity during formation of the primary antibody repertoire. In sheep, B cells mutate their Ig receptor during antigen-independent development in the lymphoid follicles of ileal Peyer's patches, but this process is arrested when these same B cells are cultured in vitro. We have used these differences between in vivo and in vitro B cell development to perform a cDNA subtraction between these two cell populations, in order to search for genes that might be involved in the hypermutation process. We describe in this paper the characterization of two genes, highly expressed in sheep ileal Peyer's patch B cells and also in centroblasts of human tonsils: deltex (Drosophila) homolog 1 (DTX1), which is related to the Notch pathway and a new Kelch-like protein, KLHL6. The putative role of these proteins, which are more likely involved in the germinal center B cell differentiation pathway than in the hypermutation mechanism per se, is discussed. 相似文献