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101.
The antigen 85 complex vaccine against experimental Mycobacterium leprae infection in mice 总被引:1,自引:0,他引:1
The proteins in culture filtrate derived from Bacillus Calmette-Guérin (BCG) were examined for protection against infection by Mycobacterium leprae. Immunization with the major secreted proteins, antigen 85 complex (Ag 85) A, B and C, induced effective protective immunity against multiplication of M. leprae in the foot pads of mice. The most effective protection was observed when mice were immunized with Ag 85A. A single immunization with Ag 85 could induce antigen-specific interferon gamma (IFNgamma) synthesis and more effective protection than live BCG vaccine. This study demonstrates that Ag 85 is an important immunoprotective molecule against leprosy infection. 相似文献
102.
Hiroyasu Ishikura Yasunari Uedono Kazunobu Yamagami Takashi Arai Naoshi Takeyama Takaya Tanaka 《Surgery today》1996,26(9):694-699
We examined the effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) and cefmetazole sodium on survival, neutrophil count, and neutrophil function in rats with peritonitis produced by cecal ligation and puncture. Rats with peritonitis received either rhG-CSF (50 or 100 g/kg) with or without cefmetazole (50 mg/kg) for 3 days, cefmetazole alone, or no treatment and were evaluated as controls. The mortality rate of all treated rats was significantly lower than that of the untreated rats. The survival rate was 57.1% for the rats given both rhG-CSF and cefmetazole, but there was no significant improvement of survival as compared with cefmetazole therapy alone. Treatment with rhG-CSF at 100 |Gmg/kg caused the circulating neutrophil count to increase significantly. The phagocytic activity for latex beads and neutrophil H2O2 production showed a greater enhancement by phorbol myristate acetate (PMA) in the untreated rats, thus indicating that neutrophils from treated rats were more activated. These findings show that rhG-CSF can improve survival and neutrophil function in rats with peritonitis, while combined therapy with cefmetazole was also found to be beneficial. 相似文献
103.
S Ikeda M Kuroki M Haruno S Oikawa H Nakazato G Kosaki Y Matsuoka 《Molecular immunology》1992,29(2):229-240
Antigenic epitopes of carcinoembryonic antigen (CEA) and non-specific cross-reacting antigen (NCA) were analysed in relation to their domain structures [domains N, I (A1-B1), II (A2-B2), III (A3-B3) and M for CEA and domains N, I (A1-B1), and M for NCA]. We reconstructed cDNAs for CEA-N, CEA-N-I, CEA-N-I-II, CEA-N-I-II-III-M (CEA-whole), NCA-N, NCA-N-I and NCA-N-I-M (NCA-whole), which were expressed in Chinese Hamster Ovary (CHO) cells. The recombinant proteins were purified by immunoadsorption and gel filtration. Their mol. wts judged from Western blotting were 17,000-26,000 for CEA-N, 70,000 for CEA-N-I, 150,000 for CEA-N-I-II, 165,000 for s-CEA-whole which was spontaneously released from cells into culture medium, 180,000 for p-CEA-whole which was solubilized with phosphatidylinositol specific phospholipase C (PI-PLC) from cells, 18,000-25,000 for NCA-N, 63,000 for NCA-N-I, and 96,000 for p-NCA-whole which was solubilized with PI-PLC from cells. The divergence of the observed mol. wts from those calculated from cDNA sequences seems to indicate that these recombinant proteins are highly N-glycosylated. By enzyme immunoassays, the immunoreactivities of the purified recombinant proteins were tested with 25 distinct anti-CEA monoclonal antibodies (MAbs), each representative of 25 different subgroups within five groups (Groups 1-5) previously classified by us in terms of the reactivity with CEA and CEA-related antigens. Twenty-one MAbs previously shown to react with different protein epitopes of the CEA molecule allow to define six groups (A-F) of epitopes according to their expression by different domains of the CEA and NCA molecules. Among four epitopes common to CEA and NCA, two were found to be present on domain N (Group A) and two on domain I (Group B). Among 15 epitopes absent from NCA but expressed by CEA and normal fecal antigens (NFAs), four were on domain N (Group C), five on domain I (Group D) and six on domain II (Group E). Two epitopes were previously described as "CEA distinctive", because they were recognized by MAbs reacting with CEA but not with the NFAs. These two epitopes (Group F) were found to be expressed by p-CEA-whole but not by s-CEA-whole. The latter results suggest that the Group F epitopes are located on a part of the domain III close to the anchoring device of the CEA molecule.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
104.
Bitoh H 《Journal of anesthesia》1992,6(3):247-254
Oxygen free radicals (OFRs) have been reported to play pivotal roles in the pathogenesis of cell damage induced by ischemia and reperfusion. The efficacy of recombinant human superoxide dismutase (rh-SOD) in the treatment of circulatory disorders after reperfusion of the splanchnic area was investigated in rats. All rats died within 3 hours after release of 60-min superior mesenteric artery occlusion (SMAO) when no treatment was given. Animals which received rh-SOD, 2mg·100g–1BW, at reperfusion followed by a continuous infusion of rh-SOD 0.67mg·100g–1BW·hr–1, exhibited prolonged survival times compared with no treatment rats (231 ± 35min and 149 ± 43min, respectively). Mean blood pressure in rats treated with rh-SOD was higher than in controls after reperfusion, and was concomitant with improvement in splanchnic perfusion. The results suggest excessive activity of OFRs in reperfused organs and a possible scavenging effect of rh-SOD as a means of eliminating them.(Bitoh H: Recombinant human-type SOD attenuates circulatory disorders after reperfusion of splanchnic organs in rats. J Anesth 6: 247–254, 1992) 相似文献
105.
Akio Kanetoshi Eiji Katsura Hiroshi Ogawa Tohru Ohyama Hiroyasu Kaneshima Toshiaki Miura 《Archives of environmental contamination and toxicology》1992,23(1):91-98
Acute toxicity of 2,4,4-trichloro-2-hydroxydiphenyl ether (Irgasan® DP300) (I) and its three chlorinated derivatives, 2,3,4,4-tetrachloro-2-hydroxydiphenyl ether (II), 2,4,4,5-tetrachloro-2-hydroxydiphenyl ether (III) and 2,3,4,4,5-pentachloro-2-hydroxydiphenyl ether (IV), in mice were examined by intraperitoneal injection. The LD50 values of Irgasan DP300, II, III and IV were 1,090, 710, 650 and 430 mg/kg, respectively.The percutaneous absorptions of these tritiated compounds were also examined by the application on the backs of mice. The radioactivities in most tissues reached to the maximal levels at 12 h or 18 h after dosing, which corresponded to 11–76% of the maximal levels given by the oral administration (Kanetoshi et al. 1988a). These results show the high percutaneous absorbability of Irgasan DP300 and its chlorinated derivatives.The intraperitoneal administrations of III and IV to rats induced hepatic microsomal aminopyrine N-demethylase and aniline 4-hydroxylase activities similarly to phenobarbital. These chlorinated derivatives also increased cytochrome P-450 content, and the activities of aminopyrine N-demethylase and N-methylaniline N-demethylase in hepatic microsomes from mice. The extents of the increases were similar to those by phenobarbital and 3-methylcholanthrene. 相似文献
106.
James A. Fyfe Lilia M. Beauchamp Anthony O. Caggiano Raymond D. Price Takayuki Yamaji Nobuya Matsuoka Thomas A. Krenitsky 《Drug development research》2004,62(1):49-59
The ability of endogenous neurotrophins, including nerve growth factor (NGF), to promote the survival and development of neurons provides convincing evidence for their therapeutic potential, despite significant barriers to their successful clinical use. Many of these barriers might be surmountable, however, by strategies that enhance endogenous neurotrophin signaling. We evaluated a series of substituted pyrimidines for their ability to enhance the effects of NGF. KP544 [2‐amino‐5‐(4‐chlorophenylethynyl)‐4‐(4‐trans‐hydroxycyclohexylamino) pyrimidine] amplified NGF‐induced neurite outgrowth of PC12 cells approximately 2‐fold at 2 µM. KP544 also enhanced choline acetyltransferase activity, a marker of differentiation induced by either NGF or by cyclic AMP, by 3‐ to 8‐fold, with a 2‐fold amplification at 0.12–0.3 µM. This amplification occurred at all concentrations of NGF used including those that maximally stimulated the cells. KP544 did not increase the levels of phosphorylated mitogen‐activated protein kinases (MAPK) above that seen with NGF alone. These studies suggested that KP544 functions within the cell at a site that is downstream from or independent of MAPK signaling. NGF‐induced neurite outgrowth in a human cell line (SH‐SY5Y neuroblastoma cells) was also enhanced with KP544 treatment. Primary embryonic rat cortical cultures were used to extend the observations beyond the studies with the immortalized cell lines. In addition to effects on neurite outgrowth, KP544 protected these cells from glutamate‐induced death. Overall, the data suggest that KP544 can selectively interact in the differentiation pathway downstream of MAPK in a manner that amplifies nerve growth factor and cyclic AMP effects and is also neuroprotective. Drug Dev. Res. 62:49–59, 2004. © 2004 Wiley‐Liss, Inc. 相似文献
107.
Proteasome inhibitor, bortezomib, potently inhibits the growth of adult T-cell leukemia cells both in vivo and in vitro. 总被引:22,自引:0,他引:22
Adult T-cell leukemia (ATL) is a fatal neoplasm derived from CD4-positive T-lymphocytes, and regardless of intensive chemotherapy, its mean survival time is less than 1 year. Nuclear factor-kappaB (NF-kappaB) activation was reported in HTLV-I associated cells, and has been implicated in oncogenesis and resistance to anticancer agents and apoptosis. We studied the effect of a proteasome inhibitor, bortezomib (formerly known as PS-341), on ATL cells in vitro and in vivo. Bortezomib could inhibit the degradation of IkappaBalpha in ATL cells, resulting in suppression of NF-kappaB and induction of cell death in ATL cells in vitro. Susceptibilities to bortezomib were well correlated with NF-kappaB activation, suggesting that suppression of the NF-kappaB pathway was implicated in the cell death induced by bortezomib. Although the majority of the cell death was apoptosis, necrotic cell death was observed in the presence of a caspase inhibitor, z-VAD-fmk. When bortezomib was administered into SCID mice bearing tumors, it suppressed tumor growth in vivo, showing that bortezomib was effective against ATL cells in vivo. These studies revealed that bortezomib is highly effective against ATL cells in vitro and in vivo by induction of apoptosis, and its clinical application might improve the prognosis of patients with this fatal disease. 相似文献
108.
109.
Asaka Takahashi Hiroki Matsuoka Keiichi Yamada Yasushi Uda 《Food and chemical toxicology》2005,43(4):521-528
3-Allyl-5-substituted 2-thiohydantoins (ATH-amino acids) derived from allyl isothiocyanate and amino acids can inhibit the mutagenicity of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) in the Salmonella assay. In this report, we studied possible mechanisms for the inhibition using rat liver S9 in assays for ethoxyresorufin O-deethylase (EROD), a marker activity for cytochrome P450 1A (CYP1A), which activates heterocyclic amines, and the Salmonella assays with the direct-acting mutagen 2-hydroxyamino-3-methylimidazo[4,5-f]quinoline (N-hydroxy-IQ). Quantitative analysis of ATH-amino acids and IQ during incubation with rat liver S9 fraction by HPLC showed that ATH-amino acids could act as S9-inhibitors, thereby inhibiting metabolic activation of IQ. Among the tested ATH-amino acids, ATH-Phe, ATH-Trp, ATH-Leu and ATH-Val showed a dose-dependent inhibition of EROD activity. ATH-Gly, ATH-Glu, and ATH-Asp behaved as blocking agents toward N-hydroxy-IQ, but exhibited no inhibition of EROD activity. 相似文献
110.
Okumi M Matsuoka Y Tsukikawa M Fujimoto N Sagawa S Itoh K 《Hinyokika kiyo. Acta urologica Japonica》2000,46(12):887-890
We report a case of a compound adrenal medullary tumor. A 63-year-old woman was referred to our hospital for examination of a right adrenal tumor, incidentally found by abdominal computed tomography (CT). CT and magnetic resonance imaging (MRI) revealed a round heterogeneous tumor, 5 cm in diameter, on the upper pole of the right kidney. A view of the total body scan demonstrated the uptake into the tumor after the injection of 123I-metaiodobenzyl-guanidine. Serum and urinary adrenaline levels were slightly elevated, and urinary excretion of vanillylmandelic acid was markedly elevated. Her blood pressure was normal. From these findings, the tumor was suspected to be a pheochromocytoma of the right adrenal gland and was resected reteroperitoneally. Pathological diagnosis was a compound adrenal medullary tumor, which was composed of pheochromocytoma and ganglioneuroma. This combination of the adrenal medullary tumor is extremely rare, and to date this case may be the sixth case in the Japanese medical literature. 相似文献