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51.
M Tanaka TR Cummins K Ishikawa SD Dib-Hajj JA Black SG Waxman 《Canadian Metallurgical Quarterly》1998,9(6):967-972
In contrast to conventional T cells, natural killer (NK) 1.1+ T cell receptor (TCR)-alpha/beta+ (NK1+T) cells, NK cells, and intestinal intraepithelial lymphocytes (IELs) bearing CD8-alpha/alpha chains constitutively express the interleukin (IL)-2 receptor (R)beta/15Rbeta chain. Recent studies have indicated that IL-2Rbeta/15Rbeta chain is required for the development of these lymphocyte subsets, outlining the importance of IL-15. In this study, we investigated the development of these lymphocyte subsets in interferon regulatory factor 1-deficient (IRF-1-/-) mice. Surprisingly, all of these lymphocyte subsets were severely reduced in IRF-1-/- mice. Within CD8-alpha/alpha+ intestinal IEL subset, TCR-gamma/delta+ cells and TCR-alpha/beta+ cells were equally affected by IRF gene disruption. In contrast to intestinal TCR-gamma/delta+ cells, thymic TCR-gamma/delta+ cells developed normally in IRF-1-/- mice. Northern blot analysis further revealed that the induction of IL-15 messenger RNA was impaired in IRF-1-/- bone marrow cells, and the recovery of these lymphocyte subsets was observed when IRF-1-/- cells were cultured with IL-15 in vitro. These data indicate that IRF-1 regulates IL-15 gene expression, which may control the development of NK1+T cells, NK cells, and CD8-alpha/alpha+ IELs. 相似文献
52.
TR Kramer MB Powell MM Wilson J Salvatore HE Grossniklaus 《Canadian Metallurgical Quarterly》1998,82(8):953-960
Lectins are sensitive probes which bind carbohydrate structures specifically. In this study, we modified the lectin staining procedure for sensitive detection of carbohydrate structures in formalin-fixed, paraffin-embedded sections of normal and heterologous serum-induced fibrotic livers. The liver sections were heated in hot distilled water at 100 degrees C for 10 min (thermo-treatment: TT), and then stained with 24 different lectins. In comparison with the results from sections without TT (nonTT), enhanced and/or alternated staining patterns of 19 lectins were demonstrated in sections with TT, and enhanced staining of Vicia villosa agglutinin seen in Kupffer cells was noted. Interestingly, no positive staining was seen with Dolichos biflorus agglutinin, peanut agglutinin or soybean agglutinin (SBA), which recognize O-linked carbohydrate chains, in Kupffer cells of non-TT sections, but strong positive staining was demonstrated in those of TT sections. SBA-positive staining in the cytoplasm of some scattered hepatocytes located in the periportal and perifibrous zones and central zone of pseudolobules was demonstrated only in the fibrotic liver sections with TT. Such findings indicate the heterogeneity of hepatocytes in the liver with fibrosis. Formalin fixation causes masking of lectin binding sites, especially O-linked carbohydrate chains, and TT may recover such masking reactions. TT improved the staining reactions for many lectins in formalin-fixed, paraffin-embedded liver sections, and new staining patterns appear after TT. Modified TT staining procedures may be useful for the diagnosis and prognosis of liver fibrosis. 相似文献
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AJ Murray J Cavalieri MJ D'Occhio TR Whyte LJ Maclellan LA Fitzpatrick 《Canadian Metallurgical Quarterly》1998,50(1-2):11-26
The aim of this study was to determine the effect on ovarian follicular growth and atresia, of acute treatment with either 100 mg of progesterone (n = 10), 200 mg of progesterone (n = 10), 10 mg of oestradiol + 100 mg of progesterone (n = 10), 10 mg of oestradiol (n = 10) or no treatment (n = 10), given on Day 10 of a 17-day treatment with a norgestomet implant in randomly cycling Bos indicus heifers. The fate of the dominant follicle on Day 10, emergence of the new cohort of follicles and the intervals from implant removal to ovulation were recorded by ultrasonography. Plasma concentrations of Luteinizing hormone (LH), progesterone and oestradiol were determined during the time when the norgestomet implant was in place. All treatments resulted in the emergence of a new cohort of follicles within 5 days of administration. The day of emergence of the ovulatory follicle tended to be delayed after treatment with 100 mg of progesterone (2.7 +/- 0.3 days after treatment), 200 mg of progesterone (3.7 +/- 0.5 days after treatment), 10 mg of oestradiol + 100 mg of progesterone (4.4 +/- 0.2 days after treatment) and 10 mg of oestradiol (4.6 +/- 0.4 days after treatment) compared to control heifers (1.4 +/- 1.4 days after time of treatment). The mean interval from implant removal to onset of oestrus was significantly shorter after treatment with 100 mg of progesterone (38.4 +/- 2.6 h) than after treatment with 200 mg of progesterone (61.5 +/- 3.9 h) but otherwise, the mean interval from implant removal to onset of oestrus did not differ. Oestrus synchrony, measured by the sample standard deviation of oestrus onset, was tighter in all treatment groups compared to untreated control heifers. The mean interval from implant removal to ovulation did not differ significantly between groups. The synchrony of ovulation, measured by the sample standard deviation of the interval from implant removal to ovulation, was significantly tighter after treatment with 100 mg of progesterone, 200 mg of progesterone and 10 mg of oestradiol compared to control heifers. Treatment with 10 mg of oestradiol resulted in ovulation in seven of 10 heifers before implant removal, three of which failed to ovulate after implant removal. Progesterone administered on Day 10 lowered plasma LH concentrations (P < 0.05), whereas treatment with oestradiol caused a surge of LH and ovulation. Progesterone administered with oestradiol prevented the LH surge. A combination treatment of oestradiol and progesterone given on Day 10 of a 17-day norgestomet treatment in a range of follicular states resulted in the consistent emergence of a new cohort of follicles which included the eventual ovulatory follicle. 相似文献
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OBJECTIVE: The aim of this study was to determine if omeprazole improves pulmonary function and quality of life in asthmatics with gastroesophageal reflux. METHODS: This was a double blind, randomized, placebo-controlled cross-over trial. After a 4-wk lead-in period, nine patients with documented asthma and gastroesophageal reflux, were prescribed either omeprazole 20 mg, daily or placebo for 8 wk and then crossed over to the alternate treatment. Outcome measurements included: forced expiratory volume at 1 s (FEV1), peak expiratory flow rate (PEFR), and responses on the Asthma Quality of Life Questionnaire, a validated disease specific measure of functional status. RESULTS: After omeprazole treatment, compared with placebo, patients had higher mean morning and evening PEFR, mean absolute difference (95% CI): morning: 37.8 L/min. (10.9-64.6), evening: 31.2 (3.2-59.2). Omeprazole treatment led to higher mean overall scores on the Asthma Quality of Life Questionnaire, and on the subdomains of activity limitation, symptoms, and emotions (p = 0.039, 0.049, 0.024, 0.040). A trend toward higher FEV1 (mean: 15.6% difference) with omeprazole failed to reach statistical significance (p > 0.2). CONCLUSIONS: After taking omeprazole for 8 wk, asthmatics with GER have better PEFR and quality of life than after placebo. 相似文献
60.
Neospora caninum is an apicomplexan parasite which is morphologically and ultrastructurally very similar to Toxoplasma gondii. In order to identify molecules involved in host cell entry and subsequent modification of the parasitophorous vacuole, a polyclonal antiserum directed against N. caninum tachyzoites was raised in a rabbit. Subcellular fractionation of tachyzoites was performed using the non-ionic detergent Triton-X-114. Membrane fractions were analysed by immunoblotting using the polyclonal antiserum. One of the immunoreactive protein bands had a mol. wt of 33,000 and was subsequently named Nc-p33. Affinity-purified anti-Nc-p33 antibodies were used to characterise this polypeptide using SDS-PAGE, isoelectric focusing, Western blot analysis and immuno-EM. Nc-p33 was found in two isolates of N. caninum (NC-1 and Liverpool), but could not be detected in T. gondii tachyzoites. Immunogold EM revealed that Nc-p33 constituted a dense granule-associated protein, and Western blotting demonstrated that Nc-p33 was most likely identical to the recently described antigen NCDG1. Shortly after invasion, this dense granule protein was targeted to the parasitophorous vacuole membrane, and, at later timepoints after infection, was also found on the parasitophorous vacuolar network. This suggested that Nc-p33 could play a functional role in the modification of the parasitophorous vacuole and its membrane. 相似文献