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1.
The antibody responses to membrane and early antigens and thymidine kinase of varicella-zoster virus (VZV) were studied in sera during both varicella and zoster by a test with fluorescent antibody to membrane antigen (FAMA), staining the biochemically transformed cells by the immunofluorescent technique and neutralization of virus-specific thymidine kinase activity, respectively. Similar increases in FAMA antibody titers were demonstrated in sera from patients with varicella and zoster. IgM was detected in both groups, but appeared earlier during varicella than during zoster. Furthermore, the antibody titers to early antigens and virus-specific thymidine kinase were higher in patients with zoster than in those with varicella. These data suggest that different types of antibody responses occur during varicella and zoster.  相似文献   
2.
The accumulation of recent data concerning the reactivity of monoclonal antibodies with particular varicella-zoster virus (VZV) glycoproteins and the mapping of several of their respective genes on the VZV genome has led to a unified nomenclature for the glycoprotein genes of VZV and their mature glycosylated products. Homologs to herpes simplex virus glycoprotein genes are noted.  相似文献   
3.
Peripheral blood mononuclear cells collected from 13 patients with chronic fatigue syndrome and 13 healthy controls were analyzed for the presence of human herpesvirus 6 (HHV-6) DNA by variant-specific polymerase chain reaction and dot blot hybridization. HHV-6 DNA was detected in 7 of 13 (53%) patients, and of those 7 patients, 4 were positive for HHV-6 variant A DNA and 3 were for variant B. No HHV-6 DNA was detected in the controls. Serum antibody titers to the late antigen and antibody prevalence to the early antigen of HHV-6 were significantly higher in the patient group. These results suggest active replication of HHV-6 in patients with chronic fatigue syndrome.  相似文献   
4.
H+-ATPase was solubilized from the tonoplast of mung bean (Vignaradiata L.) hypocotyls and purified by fast protein liquid chromatographyon a Mono Q ion-exchange column. The purified ATPase hardlycontained any phospholipid, but it did contain 10 to 15 moleculesof sterol and 25 to 30 molecules of glycolipid per ATPase molecule,and it had little activity without exogenously added phospholipids.Each individual polar head group, acylglyceride and fatty acidthat constituted a phospholipid was incapable by itself of activatingthe ATPase. Sterols and cerebroside had little activating effect.Maximal activation of ATPase was noted with asolectin or variousmolecular species of phosphatidylcholine (PC) at 0.005% to 0.01%(w/v). The activation by the various molecular species of PCwas dependent on the length and degree of unsaturation of fattyacyl chains. PC with two saturated and long fatty acyl chainsof more than 18 carbon atoms failed entirely to activate theATPase. PC, PS and PG with 1-palmitoyl (16:0)-2-oleoyl(18:1)fatty acyl chains all activated ATPase to nearly the same extentas asolectin, but the activation by PE and PA with the samefatty acyl composition was 52% and 15% of that by asolectin,respectively. The molecular species of PC with phase-transitiontemperatures below 50C activated ATPase, as determined at 38C.The dependence on temperature of the activation by the molecularspecies of PC indicated that the activation of the ATPase beganclose to the temperature of the phase transition of the PC added.These data indicate that phospholipids in the liquid-crystallinephase are essential for the catalytic activity of the ATPase. (Received June 4, 1992; Accepted January 18, 1993)  相似文献   
5.
Juvenile hormones (JHs) control a diversity of crucial life events in insects. In Lepidoptera which major agricultural pests belong to, JH signaling is critically controlled by a species-specific high-affinity, low molecular weight JH-binding protein (JHBP) in hemolymph, which transports JH from the site of its synthesis to target tissues. Hence, JHBP is expected to be an excellent target for the development of novel specific insect growth regulators (IGRs) and insecticides. A better understanding of the structural biology of JHBP should pave the way for the structure-based drug design of such compounds. Here, we report the crystal structure of the silkworm Bombyx mori JHBP in complex with two molecules of 2-methyl-2,4-pentanediol (MPD), one molecule (MPD1) bound in the JH-binding pocket while the other (MPD2) in a second cavity. Detailed comparison with the apo-JHBP and JHBP-JH II complex structures previously reported by us led to a number of intriguing findings. First, the JH-binding pocket changes its size in a ligand-dependent manner due to flexibility of the gate α1 helix. Second, MPD1 mimics interactions of the epoxide moiety of JH previously observed in the JHBP-JH complex, and MPD can compete with JH in binding to the JH-binding pocket. We also confirmed that methoprene, which has an MPD-like structure, inhibits the complex formation between JHBP and JH while the unepoxydated JH III (methyl farnesoate) does not. These findings may open the door to the development of novel IGRs targeted against JHBP. Third, binding of MPD to the second cavity of JHBP induces significant conformational changes accompanied with a cavity expansion. This finding, together with MPD2-JHBP interaction mechanism identified in the JHBP-MPD complex, should provide important guidance in the search for the natural ligand of the second cavity.  相似文献   
6.
Morbillivirus infection is a severe threat to marine mammals. Mass die‐offs caused by this infection have repeatedly occurred in bottlenose dolphins (Turiops truncatus) and striped dolphins (Stenella coeruleoalba), both of which belong to the family Delphinidae, but not in other cetaceans. However, it is unknown whether sensitivity to the virus varies among cetacean species. The signaling lymphocyte activation molecule (SLAM) is a receptor on host cells that allows morbillivirus invasion and propagation. Its immunoguloblin variable domain‐like (V) region provides an interface for the virus hemagglutinin (H) protein. In this study, variations in the amino acid residues of the V region of 26 cetacean species, covering almost all cetacean genera, were examined. Three‐dimensional (3D) models of them were generated in a homology model using the crystal structure of the marmoset SLAM and measles virus H protein complex as a template. The 3D models showed 32 amino acid residues on the interface that possibly bind the morbillivirus. Among the cetacean species studied, variations were found at six of the residues. Bottlenose and striped dolphins have substitutions at five positions (E68G, I74V, R90H, V126I, and Q130H) compared with those of baleen whales. Three residues (at positions 68, 90 and 130) were found to alternate electric charges, possibly causing changes in affinity for the virus. This study shows a new approach based on receptor structure for assessing potential vulnerability to viral infection. This method may be useful for assessing the risk of morbillivirus infection in wildlife.  相似文献   
7.
An association between FCGR3A-158 V/F polymorphism and biological responses to infliximab has been reported in Crohn’s disease (CD) in Western countries. However, little is known about the mechanism by which gene polymorphism affects the responses to infliximab. The aims of this study were to confirm the association in Japanese CD patients and to reveal the effect of gene polymorphism on biological responses to infliximab. Japanese CD patients were examined retrospectively at weeks 8 and 30. Clinical and biological responses were assessed by the Crohn’s disease activity index and C-reactive protein levels, respectively. The infliximab-binding affinity of natural killer (NK) cells from FCGR3A-158 V/V, V/F and F/F donors was examined. Infliximab-mediated antibody-dependent cell-mediated cytotoxicity (ADCC) activities were also determined using transmembrane TNF-α-expressing Jurkat T cells as target cells and peripheral blood mononuclear cells (PBMCs) from V/V, V/F and F/F donors as effector cells. Biological responses at week 8 were statistically higher in V/V patients, whereas no significant differences were observed in either clinical responses at weeks 8 and 30 or biological responses at week 30 among the three genotypes. NK cells and PBMCs from V/V patients also showed higher infliximab-binding affinity and infliximab-mediated ADCC activity, respectively. Our results suggest that FCGR3A-158 polymorphism is a predicting factor of biological responses to infliximab in the early phases. FCGR3A-158 polymorphism was also found to affect the infliximab-binding affinity of NK cells and infliximab-mediated ADCC activity in vitro, suggesting that an effect on ADCC activity influences biological responses to infliximab in CD patients.  相似文献   
8.
The attractive and characteristically sweet aroma components of baelfruit—a tropical fruit— were investigated. The aroma concentrates possessing the sweet floral and somewhat terpene-like aroma were obtained from both the pulp and peel of fresh baelfruits by means of lyophilization and ether extraction, being analyzed mainly by GC-MS, A total of 39 components were identified. Among these components, terpene alcohols and β-βonone were considered to contribute to the aroma of baelfruit. At optimum ripeness, the fruit with excellent flavor contained a large quantity of an isomeric compound of 3,7-dimethyl-1,5,7-octatrien-3-ol. This compound couldn’t be found in unripe fruit, and seems to be ?mportant in making the baelfruit flavor attractive.  相似文献   
9.
The aroma constituents of the highest quality pouchong tea were characterized by GC–MS. Forty-eight components, including five newly identified compounds were characterized. GC peak area percentages of the main components in pouchong tea were compared with those of jasmine tea to differentiate compounds contributing to the aroma characteristics of pouchong tea with superior floral elegant flavor. Nerolidol, jasmine lactone, methyl jasmonate, indole, benzyl cyanide and linalool oxides were found in much higher concentration in pouchong tea than in jasmine tea. These compounds seemed to contribute to the aroma characteristics of the highest quality pouchong tea.  相似文献   
10.
With an assumption that the laver-like odor of green tea is due to dimethyl sulfide, an attempt to isolate dimethyl sulfide from commercial green tea was made, and the identification of dimethyl sulfide was successful by making the co-ordinated compound with mercuric chloride, 2 (CH3) 2S·3HgCl2. In addition, the presence of methylmethionine sulfonium salt in tea extract as a precursor of dimethyl sulfide was examined.  相似文献   
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