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51.
Summary.  In order to identify the products of the equine herpesvirus type 4 (EHV-4) gI and gE genes, we have constructed recombinant vaccinia viruses containing the putative gI or gE genes. These recombinant viruses synthesized EHV-4 gI and gE with apparent molecular masses of 75 and 80 kDa, respectively. Antibodies raised against both recombinant viruses detected a 75 kDa gI and a 95 kDa gE in EHV-4-infected cells. The results also suggest that the EHV-4 gI and gE would form a complex like in other herpesviruses. Received October 29, 1999 Accepted January 21, 2000  相似文献   
52.
Japanese cedar pollinosis is a typical allergic disease and has recently become a big social problem. Many population are suffering from this disease every year from the end of February to the beginning of April. In this study, we planned to examine the role of platelet-activating factor (PAF) in this disease, because PAF has been known to be one of the potent chemical mediators in allergic and inflammatory reactions and many evidences indicate that PAF is deeply involved in the pathogenesis of bronchial asthma, a typical allergic disease. We measured the concentrations of the PAF derivative (lyso-PAF) in serum from patients with cedar pollinosis during the pollen season. The level of lyso-PAF in serum from untreated patients with cedar pollinosis (87.8 +/- 8.7 unit.) was significantly higher than that in healthy control (54.9 +/- 7.7 unit.). We also tested the effect of an anti-allergic drug on the level of serum lyso-PAF of cedar pollinosis. Eighteen pairs of serum samples from patients with cedar pollinosis were employed in this study. Lyso-PAF levels after two weeks' therapy with ketotifen (2 mg/day), an anti-allergic drug, decreased the levels significantly (from 82.6 unit to 41.3 unit). These results suggest that PAF could play some important role in cedar pollinosis and that the clinical effect of anti-allergic drug could be partially due to the anti-PAF action.  相似文献   
53.
For evaluation of the degree of senescence in SAM-P, accelerated senescence prone mouse, formerly called SAM or prone series or P-series, consisting of SAM-P/1, SAM-P/2, SAM-P/3 and SAM-P/4 corresponding to P-1, P-2, P-3 and P-4 series, respectively, in the previous reports, and in SAM-R, accelerated senescence resistant mouse, formerly called resistant series or R-series, consisting of SAM-R/1, SAM-R/2 and SAM-R/3 corresponding to R-1, R-2 and R-3 series, respectively, in the previous reports, the grading score system was adopted. The items to be examined in this system include 11 categories selected from the clinical signs and gross lesions considered to be associated with the aging process. The degree of the senescence in each category was graded from 0 to 4 according to the detailed criteria devised in our laboratory. After 8 months of age each mouse was examined every 4 months, and some of the mice were examined after 2 months of age.In almost all categories, the grading score and incidence began to increase from 4 or 6 months of age and continued to increase with advancing age in both SAM-P and SAM-R. The increase, however, was more marked in SAM-P than in SAM-R. The slow but steady increase in the SAM-R levelled out at 24 months of age and was comparable to that of 12 months of age in SAM-P. In both SAM-P/1 at 8 months of age and SAM-R/2 at 12 months of age, there was a significant reverse correlation between total score of this grading score system and length of residual life after examination.Systematic and extensive studies using the grading score system showed that if the validity of the system is, based on “irreversibility” and “universality” of the changes in  相似文献   
54.
55.
Decreased activity of debrisoquine 4-hydroxylase (CYP2D6), which participates in hepatic metabolism of several frequently used neuroleptics and antidepressants, is inherited as an autosomal recessive trait through polymorphic CYP2D6 gene alleles. In eastern Orientals, a C --> T substitution at nucleotide 188 (Pro34Ser) is primarily responsible for decreased ability to metabolize CYP2D6 substrates. We therefore studied a possible association between neuroleptic malignant syndrome (NMS) and the C188T mutation. We examined the frequency of the C188T mutation by polymerase chain reaction and restriction fragment length polymorphism analysis in 36 Japanese patients previously diagnosed with NMS and 107 neuroleptic-treated schizophrenic patients with no NMS history. The C188T allele frequency was 0.417 in NMS patients and 0.463 in patients without NMS. No significant allele or genotype associations were observed. We cannot conclude that low CYP2D6 activity genotype causes susceptibility to NMS in Japanese patients.  相似文献   
56.
57.
In bone marrow, hematopoiesis is thought to depend on special microenvironments known as niches that maintain blood cells. However, the identity of niches and interaction of blood cells with niches remain poorly understood. Here we identify stage-specific cellular niches for B lymphopoiesis. The earliest precursors, pre-pro-B cells and end-stage B cells, plasma cells require CXC chemokine ligand (CXCL)12. CXCL12-expressing cells are a small population of stromal cells, scattered throughout bone marrow and located some distance from the cells expressing interleukin (IL)-7. Multipotent hematopoietic progenitors are attached to the processes of CXCL12-expressing cells and pre-pro-B cells adjoin their cell bodies. Maturer pro-B cells that require IL-7 have moved away and adjoin the IL-7-expressing cells. Plasma cells again seed CXCL12-expressing cells. We demonstrate the B lymphocyte characteristic location and movement between specific niches within bone marrow during development and suggest that CXCL12 maintains the cells in the niche.  相似文献   
58.
This paper describes a new ring-opening-closing alternating copolymerization (ROCAC) of 2-methyl-2-oxazoline (five-membered cyclic imino ether, 1 ) with N-methyldiacrylamide ( 2 ). The reaction of a 1 : 1 monomer feed ratio proceeded without any added catalyst to give an alternating copolymer 3 having two structural units formed by ring-opening and ring-closing (cyclization). The structure of copolymer 3 was determined by 1H, 13C NMR, and IR spectroscopies. The extent of cyclization was at most 65%. The copolymerization was reasonably explained by a mechanism of propagation via zwitterion intermediates.  相似文献   
59.
Myristoylated alanine-rich C-kinase substrate (MARCKS) is a major in vivo substrate for protein kinase C in the brain and has been implicated in cellular processes associated with cytoskeletal restructuring such as synaptic trafficking and neurotransmitter release. A phosphorylation-site specific antibody against Ser159-phospho-MARCKS (pS159-Mar-Ab) revealed that MARCKS is phosphorylated at Ser159 by Rho-kinase and that its phosphorylation is inhibited by the Rho-kinase specific inhibitor H-1152. Since the function of MARCKS is regulated by phosphorylation at multiple sites, here we examined the involvement of Rho-kinase in relation to phosphorylation of MARCKS at Ser159 in inflammatory and neuropathic pain by H-1152. When intrathecally administered 10 min before s.c. injection of formalin, H-1152 at 10 and 100 ng attenuated the second-phase, but not the first-phase, pain-like behaviors in the formalin test. Neuropathic pain induced by selective L5 spinal nerve transection was also relieved by intrathecal injection of H-1152. Nitric oxide synthase activity visualized by NADPH diaphorase histochemistry increased in the superficial layer of the spinal cord 30 min after formalin injection and 7 days after nerve transection, which were blocked by H-1152. Phosphorylation of MARCKS at Ser159 was detected in the spinal cord by pS159-Mar-Ab and the level of phosphorylation increased in the superficial layer after nerve transection. In contrast, immunoreactivities of neuronal nitric oxide synthase and MARCKS did not change significantly in the spinal cord before and after nerve transection. Taken together, the present study demonstrates that Rho-kinase is involved in inflammatory pain and the maintenance of neuropathic pain through phosphorylation of MARCKS at Ser159.  相似文献   
60.
The ability of recombinant murine (rMu) interferon (IFN)-gamma to activate anti-Salmonella-activity in normal mice and beige mutant (bg/bg) mice with Chediak-Higashi syndrome (CHS) was examined. Previous intraperitoneal (i.p.) injection of rMuIFN-gamma (10(4) U per mouse) significantly hindered the bacterial growth in the peritoneal cavities, spleens and livers of the mice after the i.p. infection with Salmonella enteritidis No. 11 strain. It was also effective on the beige mice that have phagocytic cells with a genetically impaired bactericidal function, suggesting that IFN-gamma activates the pathway irrelevant to the beige mutation. The effect was the maximum, when IFN-gamma was given 6 h before the challenge. The effect seemed to be due to the augmentation of bactericidal capacity rather than the prevention of systemic spread of bacteria. Recombinant human IFN-alphaA/D (10(2)-10(6) U per mouse), which produced effects identical to those of murine IFN-beta, did not show such a bactericidal effect. Bactericidal activity enhancement was also seen in mice that had been injected with a small amount of rMuIFN-gamma (10(2) U) and bacterial lipopolysaccharide (LPS) (10 ng) together at 6 h before the challenge, although the IFN-gamma or LPS alone at these doses produced very little if any effect. Bactericidal effect enhancement was seen in mice that had been injected with IFN-gamma at 6 h and LPS at 3 h before the challenge, while it could be hardly seen in mice injected with them in a reversed order.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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