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1.
Livia Poenaru Laetitia Castelnau Agnès Choiset Y. Rouquet F. Thepot 《Human genetics》1985,69(4):378-379
Summary Fourteen lysosomal enzymes were compared in 20 cultured cell lines from chorionic biopsy and corresponding embryonic tissue after voluntary abortions. Enzymatic expression appears to be similar in cultured cells from both sources with some slightly higher levels for chorionic villi. We stress the importance of culturing chorionic villi especially in the case of enzymes (-L-iduronidase) or diseases (I cell disease) whose expression is unusual in fresh trophoblast tissue. 相似文献
2.
Prevention of murine cryoglobulinemia and associated pathology by monoclonal anti-idiotypic antibody 总被引:4,自引:0,他引:4
F Spertini Y Donati I Welle S Izui P H Lambert 《Journal of immunology (Baltimore, Md. : 1950)》1989,143(8):2508-2513
A murine IgG3 mAb, clone 6-19, derived from non-manipulated autoimmune MRL/MpJ-lpr/lpr mice is a rheumatoid factor specific for IgG2a and is able to generate cryoglobulins via nonspecific IgG3 Fc-Fc interaction. Intraperitoneal passive transfer of ascites containing the 6-19 mAb into BALB/c mice induces, within 18 h, remarkable pathology characterized by skin vasculitis and acute glomerulonephritis associated with cryoglobulinemia. In order to evaluate the possibility of modulating the development of tissue lesions by an anti-Id antibody, we have raised an IgG2b anti-Id mAb specific to the 6-19 mAb. The cryoprecipitation of 6-19 mAb was completely inhibited in the presence of excess amounts of anti-Id mAb in vitro. In vivo, pretreatment of BALB/c mice with anti-6-19 anti-Id mAb inhibited development of skin vasculitis and glomerulonephritis induced by the 6-19 mAb. The cryoglobulin formation was markedly diminished due to enhanced elimination of the 6-19 mAb from the circulation. In contrast, pretreatment with an IgM anti-IgG3 rheumatoid factor mAb neither protected nor aggravated the development of tissue lesions. These results suggest possible implications in the anti-Id treatment of similar vascular diseases in man. 相似文献
3.
Summary Bioleaching of manganese (IV) oxide with Thiobacillus thiooxidans has been studied in media with and without sulfur, ferrous sulfide and ferrous sulfate. The knowledge of the role played by the bacteria and the reducing substances suggest that the leaching of manganese (IV) ores through the use of thiobacteria is only justified when suitable amounts of sulfur or metal sulfides are present. 相似文献
4.
The addition of a surfactant agent (Tween 80) to a medium containing sulphur and a culture of Thiobacillus thiooxidans increased the attachment of bacteria to sulphur, the rate of sulphur oxidation and sulphuric acid production. This acid was used to dissolve phosphorus from calcium phosphate. The yield was higher than reported for other microorganisms although dissolution was not increased significantly by Tween addition. 相似文献
5.
6.
Livia Pinzoni Lisa Locatello Clelia Gasparini Maria Berica Rasotto 《Journal of evolutionary biology》2023,36(8):1198-1207
There is growing evidence that the female reproductive fluid (FRF) plays an important role in cryptic female choice through its differential effect on the performance of sperm from different males. In a natural spawning event, the male(s) may release ejaculate closer or further away from the spawning female. If the relative spatial proximity of competing males reflects the female pre-mating preference towards those males, then favoured males will encounter higher concentrations of FRF than unpreferred males. Despite this being a common situation in many external fertilizers, whether different concentrations of FRF can differentially influence the sperm performance of distinct male phenotypes (favoured and unfavoured by the female) remains to be elucidated. Here, we tested this hypothesis using the grass goby (Zosterisessor ophiocephalus), a fish with distinct territorial-sneaker reproductive tactics and female pre-mating preference towards territorial males, that consequently mate in an advantaged position and whose sperm experience higher concentrations of FRF. Our findings revealed a differential concentration-dependent effect of FRF over sneaker and territorial sperm motility only at low concentrations (i.e. at the distance where sneakers typically ejaculate), with increasing FRF concentrations (i.e. close to the eggs) similarly boosting the sperm performance of both sneaker and territorial males. The ability to release sperm close to the eggs is a prerogative of territorials, but FRF can likewise advantage the sperm of those sneakers that are able to get closer, allowing flexibility in the direction of female post-mating choice. 相似文献
7.
8.
Alessandra Cesano Sophie Visonneau Livia Cioé Steven C. Clark Daniela Santoli 《Cancer immunology, immunotherapy : CII》1995,40(3):139-151
The TALL-104 cell line, originally derived from a patient with T cell leukemia, can be maintained indefinitely in culture in the presence of interleukin-2 (IL-2) and is endowed with a highly potent major-histocompatibilitycomplex (MHC)-non-restricted tumoricidal activity both in vitro and in animal models. The present study analyzes in detail the short- and long-term effects of irradiation and cyclosporin A (CsA) treatment on the growth and tumoricidal function of this T cell clone as compared to polyclonal lymphokine-activated killer (LAK) cell preparations from healthy donors. DNA and RNA syntheses by both TALL-104 and LAK cells were irreversibly arrested a few hours after irradiation with 40 Gy. However, 4-h51Cr-release assays, performed on different days (day 1 to day 7) after irradiation, showed that the cytotoxic efficiency of TALL-104 cells against hematopoietic and solid tumor targets was only modestly reduced, whereas that of LAK cells was severely inhibited. Moreover, the cytotoxic responses to recombinant human IL-2 and IL-12, measured 18 h after irradiation and cytokine addition, were normal in the case of TALL-104 cells but were abolished in the case of LAK cells. Co-culture of IL-2-or IL-12-preactivated TALL-104 cells with a tumor target for 5 days in the absence of cytokines resulted in a lower efficiency of lysis, as compared to the non-irradiated effectors, especially if the initial stimulus was IL-12. These findings suggest the requirement of multiple cytokine stimulation for optimal expression of tumoricidal activity by lethally irradiated TALL-104 cells. CsA, while abrogating TALL-104 cell proliferation at the low dose of 0.5 g/ml, inhibited their cytotoxic function marginally only at high doses (100 g/ml). By contrast, CsA reduced dose-dependently the cytotoxicity of LAK cells starting at very low doses (0.5 g/ml). CsA did not impair the ability of TALL-104 and LAK cells to produce interferon (IFN), tumor necrosis factor (TNF) , and granulocyte/macrophage-colony-stimulatory factor (GM-CSF) in response to IL-2, IL-12, or tumor targets. Irradiation reduced drastically IFN production by LAK, but not TALL-104 cells; release of TNF and GM-CSF by either type of effector was inhibited by 10%–50%, depending on the stimulus. The high resistance of the TALL-104 cells' tumoricidal function to irradiation and immunosuppressive drugs renders this immortal T cell clone a potentially safe and effective reagent for new adoptive-transfer approaches to cancer in MHC-incompatible recipients. 相似文献
9.
Jean-Claude Dreyfus Jean-Paul Belon Sophie Gautron Gilbert Lenoir Livia Poenaru 《Biochemical and biophysical research communications》1984,119(3):841-849
The activity of seven lysosomal enzymes was determined in 25 lymphoblastoid cell lines. These lines included normal controls transformed with Epstein-Barr virus, Burkitt's lymphomas and other lymphomas with or without EBV genome.Four lines were deficient in total β-hexosaminidase activity. The deficiency was as severe as that of the variant O (Sandhoff's disease) of clinical β-hexosaminidase deficiency. The electrophoretic pattern was also similar to that observed in Sandhoff's disease.The possible mechanisms explaining the high frequency of β-hexosaminidase deficiency in lymphoblastoid cell lines are discussed. 相似文献
10.
The crystal and molecular structures of the title compounds were determined by x-ray diffractometric analysis. Torsion angles and puckering parameters are reported for both compounds. In 1 the 5 alpha-cyano group influences the A-ring conformation. The carbonate ester 3 crystallizes in the monoclinic P2(1) space group with two molecules (I and II) in the asymmetric unit. The D-ring conformation is to some extent different between I and II. 相似文献