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41.
Jian Fei Wang Irene R. Kieba Jon Korostoff Tai Liang Guo Noboru Yamaguchi Harry Rozmiarek Paul C. Billings Bruce J. Shenker Edward T. Lally 《Microbial pathogenesis》1998,25(6):317-331
Pasteurella haemolyticaleukotoxin (LKT) is a member of the RTX family of pore-forming toxins that kill bovine immune cells. Several studies have suggested that RTX toxins kill target cells by the induction of apoptosis. In the present study, BL3 bovine leukaemia cells were exposed to LKT and assessed by molecular and flow cytometric techniques that measure different aspects of apoptotic cell death. The intoxicated cells demonstrated morphological, light scatter and Hoechst 33258 staining characteristics consistent with cells undergoing apoptosis. The cells also exhibited internucleosomal DNA fragmentation and poly (ADP-ribose) polymerase (PARP) cleavage, both indicators of apoptosis. LKT-treated cells bound annexin-V-FITC indicating that phosphatidylserine groups were translocated from the inner to the outer leaflet of the cell membrane. The effect of LKT on cells was dose dependent and inhibitable by incubation with anti-LKT monoclonal antibody. Finally, an early step for induction of apoptosis appears to be the binding of LKT to a β2 integrin since pre-incubating cells with anti-β2 integrin antibodies inhibited LKT-induced apoptosis. This study provides new insights into understanding the pathogenesis of bovine pasteurellosis and could lead to the development of both preventative and therapeutic strategies for disease management. 相似文献
42.
Stephane Palazzetti Marie-Jeanne Richard Alain Favier Irene Margaritis 《Revue canadienne de physiologie appliquée》2003,28(4):588-604
We hypothesized that overloaded training (OT) in triathlon would induce oxidative stress and damage on muscle and DNA. Nine male triathletes and 6 male sedentary subjects participated in this study. Before and after a 4-week OT, triathletes exercised for a duathlon. Blood ratio of reduced vs. oxidized glutathione (GSH/GSSG), plasma thiobarbituric acid reactive substances (TBARS), leukocyte DNA damage, creatine kinase (CK), and CK-MB mass in plasma, erythrocyte superoxide dismutase (SOD) activity, erythrocyte and plasma glutathione peroxidase (GSH-Px) activities, and plasma total antioxidant status (TAS) were measured before and after OT in pre- and postexercise situations. Triathletes were overloaded in response to OT. In rest conditions, OT induced plasma GSH-Px activity increase and plasma TAS decrease (both p < 0.05). In exercise conditions, OT resulted in higher exercise-induced variations of blood GSH/GSSG ratio, TBARS level (both p < 0.05), and CK-MB mass (p < 0.01) in plasma; and decreased TAS response (p < 0.05). OT could compromise the antioxidant defense mechanism with respect to exercise-induced response. The resulting increased exercise-induced oxidative stress and further cellular susceptibility to damage needs more study. 相似文献
43.
Rademakers R Melquist S Cruts M Theuns J Del-Favero J Poorkaj P Baker M Sleegers K Crook R De Pooter T Bel Kacem S Adamson J Van den Bossche D Van den Broeck M Gass J Corsmit E De Rijk P Thomas N Engelborghs S Heckman M Litvan I Crook J De Deyn PP Dickson D Schellenberg GD Van Broeckhoven C Hutton ML 《Human molecular genetics》2005,14(21):3281-3292
44.
Discrimination of single-copy IS6110 DNA fingerprints of Mycobacterium tuberculosis isolates by high-resolution minisatellite-based typing 总被引:9,自引:0,他引:9 下载免费PDF全文
Seven isoniazid-resistant isolates with mutations in the NADH dehydrogenase (ndh) gene were molecularly typed by IS6110-based restriction fragment length polymorphism analysis. All seven isolates with the R268H mutation had identical 1.4-kb IS6110 fingerprints. High-resolution minisatellite-based typing discriminated five of these isolates; two isolates were identical. 相似文献
45.
Elisabet Costa Silvia Canudas Ivan Garcia-Bassets Silvia Pérez Irene Fernández Ernest Giralt Fernando Azorín M. Lluïsa Espinás 《Chromosome research》2006,14(5):515-526
SAP18 is a highly conserved protein that was proposed to be involved in multiple cellular processes from autophagy to gene
regulation and mRNA processing. In this paper we show that, in Drosophila, dSAP18 is a predominantly nuclear protein that associates to both chromosomes and the nuclear matrix. dSAP18 becomes nuclear
early during development, at the onset of cellularization, and remains so all through embryo development. dSAP18 is also nuclear
in salivary glands, ovaries and cultured S2 cells. Here we also show that dSAP18 forms a complex with the Drosophila homolog of pinin (dPnn), a protein factor involved in mRNA splicing. dSAP18-dPnn interaction was confirmed in vivo, through co-immunoprecipitation experiments, as well as in vitro, through GST pull-down assays. These results are discussed in the context of the possible functions played by SAP18. 相似文献
46.
An endogenous phosphorylating activity is demonstrated in the cytosol from soleus muscle of the rat which is markedly stimulated after severing the motor nerve fibers to this muscle. The [γ-32P]ATP phosphotransferase reaction is heat-labile, dependent upon Mg2+ but not Ca2+ or cyclic GMP, inhibited by a cyclic AMP dependent protein kinase inhibitor, and directly related to the amount of cytosolic protein which provides the endogenous source of both the protein kinase enzyme, ATP, cyclic AMP and phosphorylatable protein substrate. The time-course of the delayed transitory stimulation of the cytosolic phosphorylating activity of the denervated soleus may involve neurotropic factors. 相似文献
47.
48.
Patricia A. Jacobs Janice S. Matsuura Martha Mayer Irene M. Newlands 《Clinical genetics》1978,13(1):37-60
A cytogenetic survey of 475 patients in an institution for the mentally retarded is reported. The chromosomes of all patients were studied using both a non-banding and a G-banding technique in order to estimate the relative efficiency of the two technique in detecting structural rearrangements of the chromosomes. A total of 57 patients was found to have a chromosome abnormality, including five with a balanced structural rearrangement. The contribution of chromosome aberrations to the etiology of mental retardation is discussed with special emphasis on the contribution of balanced structural rearrangements. 相似文献
49.
Jakob CA Guldenschuh I Hürlimann R Müllhaupt B Müller A Ammann R Fried M Roth J 《Virchows Archiv : an international journal of pathology》1999,434(1):57-62
DNA methylation plays an important part in the regulation of gene expression. Alterations in DNA methylation in tumours have
been reported and have been used to generate hypotheses about mutagenesis and silencing of tumour suppressor genes. However,
the underlying mechanism is still poorly understood, and conflicting data on the levels of overexpression of 5′-cytosine DNA
methyltransferase in sporadic colon carcinoma have been published. We used a competitive RT-PCR assay for quantification of
mRNA of 5′-cytosine DNA methyltransferase in colon biopsies obtained from patients with hereditary colon carcinoma syndromes
and compared the results with those obtained in a control group. No significant difference was found between the flat mucosa
of FAP patients and the mucosa of the control group. In FAP and HNPCC patients, the 5′-cytosine DNA methyltransferase mRNA
levels of adenomas were significantly higher (P<0.05) than of flat mucosa in the same group, but both showed great variability from patient to patient. Our findings suggest
that the mRNA levels of methyltransferase cannot be used as predictive marker for screening in families affected by hereditary
colon carcinoma.
Received: 20 July 1998 / Accepted: 21 September 1998 相似文献
50.
Hananyah Glaubman Israel Orbach Ygal Gross Orit Aviram Irene Frieder Meira Frieman Odeda Pelled 《Psychophysiology》1979,16(5):467-470
The hypothesis that a load on focal attention prior to sleep results in subsequent changes in sleep patterns was investigated. Eight females and 2 males slept in the laboratory for 4 nights: 2 adaptation nights, 1 experimental night preceded by a focal attention load, and 1 control night preceded by relaxed activity. On the experimental night, time in bed, total sleep time, and stage REM sleep were significantly longer than on the control night. The results support the hypothesis and suggest that attention during REM sleep has a unique character. 相似文献