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961.
Mammal Research - The golden jackal (Canis aureus), a mesocarnivore, is currently expanding from eastern towards western Europe. Reproduction of the species could be confirmed in several areas in... 相似文献
962.
The humoral immune response was evaluated in male CD-1 mice fed the iron deficient (7 ppm Fe), iron sufficient (120 ppm Fe), and high-iron diets (3000 or 5000 ppm Fe) for 54 d. The IgM and IgG antibody responses against sheep erythrocytes (SRBC) determined by hemolytic plaque assay were suppressed by 65.4 and 51.2%, respectively, in the iron deficient mice. Subclinical iron deficiency was manifested by a marked reduction in hepatic iron concentration without any changes in hematocrit or body weight gain. In contrast, consumption of high-iron diets caused a marked accumulation of iron in the liver and a twofold reduction in the IgM antibody response without alteration in the IgG response. The suppression of the IgG antibody response in the iron deficient mice, however, did not result in a compensatory increase in delayed type hypersensitivity response. 相似文献
963.
Nicolette A. Gastkemper Auk S. Wubbena Felix J. H. Gimbrère Alexander de Graaff Paul Nieuwenhuis 《Cell and tissue research》1981,219(2):281-289
Summary Thoracic duct lymphocytes (TDL) were studied with respect to their capacity to give rise to germinal centres (GC) and to form primary antibody in an adoptive transfer system of the rat. Challenge with sheep erythrocytes (SRBC) 24h after lethal irradiation (900 rads) and syngeneic TDL reconstitution (108) lead to conspicuous GC activity already 7 days after transfer. In contrast, using syngeneic bone marrow (BM) in the adoptive transfer system, no GC formation was observed over the period studied (14 days after reconstitution). Reconstitution experiments using in vivo-separated T-TDL (1–5 % s-Ig+) and B-TDL (>90% s-Ig+) subpopulations, either separately or in combination, indicated that GC originate from B-TDL but require T-TDL for induction.Abbreviations BM
Bone Marrow
- TDL
Thoracic Duct Lymphocytes
- GC
Germinal Centre
- SRBC
Sheep Red Blood Cells
- GCDC
Germinal Centre-Derived Cells
- GCPC
Germinal Centre-Precursor Cells
- DAB
Mineral Salt Solution Dulbecco A + B
- FCS
Fetal Calf Serum
- PALS
Peri-Arteriolar Lymphocyte Sheath
- AFCP
Antibody-Forming Cell Precursors 相似文献
964.
Ansgar Deibel Daniel Stocker Cordula Meyer zu Schwabedissen Lars Husmann Philipp Andreas Kronenberg Felix Grimm Peter Deplazes Ccilia S. Reiner Beat Müllhaupt 《PLoS neglected tropical diseases》2022,16(1)
ObjectivesAlveolar echinococcosis (AE) is an orphan zoonosis of increasing concern in endemic areas, including Europe. It frequently presents in an advanced, inoperable stage, that requires life-long parasitostatic benzimidazole therapy. In some patients, long-term therapy leads to negative anti-Em18 antibody ELISA and PET. It is disputed, whether these patients are truly cured and treatment can be safely discontinued. Our aim was to retrospectively assess long-term outcome of 34 patients with inoperable AE who participated in a previous study to determine feasibility of benzimidazole treatment cessation.MethodsRetrospective analysis of medical charts was undertaken in all 34 AE patients who participated in our previous study. Of particular interest were AE recurrence or other reasons for re-treatment in patients who stopped benzimidazole therapy and whether baseline clinical and laboratory parameters help identify of patients that might qualifiy for treatment cessation. Additionally, volumetric measurement of AE lesions on contrast-enhanced cross-sectional imaging was performed at baseline and last follow-up in order to quantify treatment response.Results12 of 34 patients stopped benzimidazole therapy for a median of 131 months. 11 of these patients showed stable or regressive AE lesions as determined by volumetric measurement. One patient developed progressive lesions with persistently negative anti-Em18 antibody ELISA but slight FDG-uptake in repeated PET imaging. At baseline, patients who met criteria for treatment cessation demonstrated higher lymphocyte count and lower total IgE.ConclusionTreatment cessation is feasible in inoperable AE patients, who demonstrate negative anti-Em18 antibody ELISA and PET on follow-up. Close monitoring including sectional imaging is strongly advised. 相似文献
965.
Maria Malanga Hanna E. Kleczkowska Felix R. Althaus 《Journal of cellular biochemistry》1998,70(4):596-603
Recent evidence suggests that poly(ADP-ribose) may take part in DNA strand break signalling due to its ability to interact with and affect the function of specific target proteins. Using a poly(ADP-ribose) blot assay, we have found that several nuclear matrix proteins from human and murine cells bind ADP-ribose polymers with high affinity. The binding was observed regardless of the procedure used to isolate nuclear matrices, and it proved resistant to high salt concentrations. In murine lymphoma LY-cell cultures, the spontaneous appearance of radiosensitive LY-S sublines was associated with a loss of poly(ADP-ribose)-binding of several nuclear matrix proteins. Because of the importance of the nuclear matrix in DNA processing reactions, the targeting of matrix proteins could be an important aspect of DNA damage signalling via the poly ADP-ribosylation system. J. Cell. Biochem. 70:596–603. © 1998 Wiley-Liss, Inc. 相似文献
966.
967.
HEAT SHOCK PROTEIN 90C is a bona fide Hsp90 that interacts with plastidic HSP70B in Chlamydomonas reinhardtii 下载免费PDF全文
We report on the molecular and biochemical characterization of HEAT SHOCK PROTEIN 90C (HSP90C), one of the three Hsp90 chaperones encoded by the Chlamydomonas reinhardtii genome. Fractionation experiments indicate that HSP90C is a plastidic protein. In the chloroplast, HSP90C was localized to the soluble stroma fraction, but also to thylakoids and low-density membranes containing inner envelopes. HSP90C is expressed under basal conditions and is strongly induced by heat shock and moderately by light. In soluble cell extracts, HSP90C was mainly found to organize into dimers, but also into complexes of high molecular mass. Also, heterologously expressed HSP90C was mainly found in dimers, but tetramers and fewer monomers were detected, as well. HSP90C exhibits a weak ATPase activity with a Km for ATP of approximately 48 microM and a kcat of approximately 0.71 min(-1). This activity was inhibited by the Hsp90-specific inhibitor radicicol. In coimmunoprecipitation experiments, we found that HSP90C interacts with several proteins, among them plastidic HSP70B. The cellular concentration of HSP70B was found to be 2.9 times higher than that of HSP90C, giving a 4.8:1 stoichiometry of HSP70B monomers to HSP90C dimers. The strong inducibility of HSP90C by heat shock implies a role of the chaperone in stress management. Furthermore, its interaction with HSP70B suggests that, similar to their relatives in cytosol and the endoplasmic reticulum, both chaperones might constitute the core of a multichaperone complex involved in the maturation of specific client proteins, e.g. components of signal transduction pathways. 相似文献
968.
Felix J. J. A. Bianchi Nina N. Joosten Just M. Vlak Wopke van der Werf 《Biological Control》2000,19(3):252
Dose– and time–mortality relationships of baculoviruses in pest insects are important for the determination of effective spraying regimes. A series of experiments with Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) and Spodoptera exigua MNPV (SeMNPV) against synchronized populations of S. exigua larvae in greenhouse chrysanthemum was conducted. Dose– and time–mortality relationships of different virus concentrations and S. exigua target stages were determined and the area foliage consumption was measured. Crop injury was greatly reduced when S. exigua were controlled as second or third instar larvae, whereas virus applications against fourth instar larvae could not prevent considerable crop injury, even at high concentrations. SeMNPV was approximately 10 times as infectious as AcMNPV when applied on greenhouse chrysanthemum. The relative virulence of AcMNPV and SeMNPV corresponded reasonably well with previously published laboratory bioassay data. SeMNPV killed second and fourth instar S. exigua larvae approximately 12 h faster than did AcMNPV in chrysanthemum, but no difference in speed of action was found for third instar larvae. The relative speed of action of AcMNPV and SeMNPV determined in chrysanthemum and in laboratory bioassays did not correspond for third instar S. exigua larvae; laboratory bioassay data can therefore not simply be extrapolated to the crop level. 相似文献
969.
Pärli Rea Lieberherr Eva Holderegger Rolf Gugerli Felix Widmer Alex Fischer Martin C. 《Conservation Genetics》2021,22(5):673-684
Conservation Genetics - Genetic diversity is a fundamental component of biological diversity, and its conservation is considered key to ensure the long-term survival of natural populations and... 相似文献
970.
Zoidis G Papanastasiou I Dotsikas I Sandoval A Dos Santos RG Papadopoulou-Daifoti Z Vamvakides A Kolocouris N Felix R 《Bioorganic & medicinal chemistry》2005,13(8):2791-2798
A facile preparation of 2-aminomethyl-2-tricyclo[3.3.1.1(1,7)]decaneacetic acid hydrochloride 5 (AdGABA) is described. The synthesis of AdGABA involves the hydrogenation of 2-cyano-2-tricyclo[3.3.1.1(1,7)]decaneacetic acid 11, which was synthesized by two different synthetic routes. AdGABA was found to antagonize the pentylenetetrazole (PTZ) and semicarbazide (SCZ) induced tonic convulsions and exhibits analgesic activity in the hot plate test on mice. Although its mechanism of action is quite similar to that proposed previously for gabapentin (interaction with the alpha2delta subunit of the voltage gated Ca2+ channels), further studies were undertaken in order to clarify the precise mechanism of the anticonvulsant and analgesic effects of AdGABA on a molecular level. 相似文献