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991.
We have studied the proliferation and CD40 antigen expression of lymphocytes, and the cytotoxicity to monocytes, of antisense phosphorothioate oligodeoxynucleotides complementary to the SP II promoter of HBV mRNA (sequence I) and the X gene (sequence II) in patients with chronic hepatitis B. The oligo sequence I stimulated proliferation of both T and, to a lesser extent, B cells. The percentage of cells expressing CD40 in T and B cell co-cultures increased from 4.2% to 13.8% after oligo stimulation in patients, while it increased form 4.7% to 48.6% in healthy controls. The sense sequence (sequence III) of the X gene also enhanced the expression of CD40 antigen in patients with hepatitis B. The proportion of CD40 cells (26%) in a resting B-cell preparation from hepatitis B patients decreased to zero after a 5-day culture with sequence I, but IgG levels in the culture supernatant increased. The cytotoxic properties of monocytes were not influenced by the oligos. These findings indicate that antisense oligos against hepatitis B virus (HBV) have mitogenic effects on the proliferation of human lymphocytes in a non-specific manner and may activate T cells to express CD40 antigen.  相似文献   
992.
Several kinds of immunological abnormalities have been found more frequently in patients with subacute myelo-optico-neuropathy (SMON). To investigate whether the B-cell immune system is implicated in aging in patients with SMON, we examined serum levels of immunoglobulin including IgG, IgM, and IgA, and the number of CD20+ cells (B lymphocytes) and CD20+ CD23+ cells (activated B lymphocytes) using flow cytometry, and compared them with those in age-matched controls. We also investigated whether the number of HLA-DR+ cells was correlated with those of CD20+ cells, CD20+ CD23+ cells, or HLA-DR+CD3+ cells (activated T lymphocytes) in patients with SMON. Serum levels of IgG, IgM and IgA were decreased with aging both in the patients with SMON and in the controls, and no significant difference was found between the two groups. Although the patients with SMON tended to show higher levels of CD20+ and CD20+ CD23+ cells than the age-matched controls, there were no significant differences between the two groups. The number of HLA-DR+ cells was correlated not with that of CD20+ cells or CD20+ CD23+ cells, but with that of HLA-DR+CD3+ cells. In patients with SMON, it is likely that the B-cell immune system is mainly implicated in the effect of aging, but it is unlikely that other factors than aging are associated with the B-cell immune system. The increase in the number of HLA-DR+ cells associated with aging in patients with SMON reflects the increase in the number of activated T lymphocytes, and is not correlated with the changes of B lymphocytes.  相似文献   
993.
BACKGROUND: It has recently been reported that acetaldehyde induces bronchoconstriction indirectly via histamine release. However, no study has been performed to assess whether acetaldehyde worsens bronchial responsiveness in asthmatic subjects so this hypothesis was tested. METHODS: Methacholine provocation was performed on three occasions: (1) after pretreatment with oral placebo and inhaled saline (P-S day), (2) after placebo and inhaled acetaldehyde (P-A day), and (3) after a potent histamine H1 receptor antagonist terfenadine and acetaldehyde (T-A day) in a double blind, randomised, crossover fashion. Nine asthmatic subjects inhaled 0.8 mg/ml acetaldehyde or saline for four minutes. After each inhalation a methacholine provocation test was performed. RESULTS: Methacholine concentrations producing a 20% fall in FEV1 (PC20-MCh) on the P-A day (0.48 mg/ml, 95% CI 0.21 to 1.08) and T-A day (0.41 mg/ml, 95% CI 0.22 to 0.77) were lower than those on the P-S day (0.85 mg/ml, 95% CI 0.47 to 1.54). There was no change in the PC20-MCh between the P-A and T-A days. A correlation was observed between the logarithmic values of PC20-MCh (log PC20-MCh) on the P-S day and the potentiating effect of acetaldehyde on the methacholine responsiveness [(log PC20-MCh on P-A day)-(log PC20-MCh on P-S day)] (rho = 0.82). CONCLUSIONS: Acetaldehyde induces bronchial hyperresponsiveness in patients with asthma by mechanisms other than histamine release.  相似文献   
994.
Optic morphology (Om) mutations in Drosophila ananassae map to at least 22 loci scattered throughout the genome. They are semidominant, neomorphic, nonpleiotropic, and are associated with the insertion of a retrotransposon, tom. The Om(1A) gene, which is cytogenetically linked to the cut locus, was cloned using a DNA fragment of the cut locus of Drosophila melanogaster as a probe. Three of the eight alleles of Om(1A) examined have insertion of the tom element within a putative cut region. The gamma-ray-induced revertants of Om(1A) are accompanied with cut lethal mutations and rearrangements within the cut coding region. In the eye imaginal discs of the Om(1A) mutants, differentiation of photoreceptor clusters is suppressed, abnormal cell death occurs in the center and the cut protein is expressed ectopically. D. melanogaster flies transformed with a chimeric cut gene under the control of a heat-inducible promoter show excessive cell death in the region anterior to the morphogenetic furrow, suppressed differentiation to photoreceptor clusters and defect in the imaginal eye morphology when subjected to temperature elevation. These findings suggest that the tom element inserted within the Om(1A) region induces ectopic cut expression in the eye imaginal discs, thus resulting in the Om(1A) mutant phenotype.  相似文献   
995.
The design, synthesis, and antiviral activities of 6'-homoneplanocin A (HNPA, 3) and its congeners having nucleobases other than adenine, such as 3-deazaadenine (4), guanine (5), thymine (6), and cytosine (7), were described. Starting from the known cyclopentenone derivative 8, the optically active (mesyloxy)cyclopentene derivative 15 was prepared, which was condensed with nucleobases then deprotected to give target compounds 3-7. Of these compounds, HNPA showed an antiviral activity spectrum that was comparable to, and an antiviral specificity that was higher than, that of neplanocin A. HNPA proved particularly active against human cytomegalovirus, vaccinia virus, parainfluenza virus, vesicular stomatitis virus, and arenaviruses, which is compatible with an antiviral action targeted at S-adenosylhomocysteine hydrolase. HNPA appears to be a promising candidate drug for the treatment of these viruses.  相似文献   
996.
997.
We have reported our "new questionnaire of QOL (quality of life) in anti-emetic therapies during cancer chemotherapy" and demonstrated its reliability and validity. In the present study we investigated the utility of tropisetron capsules for delayed nausea and vomiting induced by cancer chemotherapies with CDDP single administration in a placebo-controlled double-blind comparative study using the questionnaire. The questionnaire was composed of the following scales: a physiological scale (appetite, feeling, vomiting, nausea), a psychological scale (sleep, mental fatigue, anxiety, pain, abdominal condition), a respiratory condition related scale (sputum, respiratory distress), an active scale (daily life in a hospital), a social relation scale (understanding of the family), a linear analogue scale for evaluation of the influence of nausea and vomiting in patient's life during 24 hours, and a face scale as the global scale. First, all patients were administered a preventive dose of tropisetron capsule on day 1 (the day of CDDP administration) and then allotted to once-daily oral administration of either a tropisetron (T group) or a placebo (P group) capsule during days 2 to 5 by a double-blind method. Chronological changes of QOL during the study period were measured by the area under the curve (AUC) generally used for calculation of blood levels of drugs. The maximum fluctuation (Difmax) of QOL scores throughout the whole study period was also evaluated. The data were collected from 114 cases, and 98 cases (51 in P group, 47 in T group) were analyzed. 1) The total score or 13 items (a modified linear analogue scale with 5 graduations), the face scale and linear analogue scale of T group were higher (better) than those of P group. 2) As for the total score of each scale, the physiological, psychological and active scales in the T group showed higher (better) levels than the P group. 3) As for the AUC values, the T group was lower (better) than the P group in most items. In AUC of the total score of 13 items, the face scale, the physiological and the psychological scales, the T group was significantly superior to the P group. 4) AUC levels of each item belonged to the physiological and the psychological scales in the T group tended to be lower (better) than the P group, and "sleep" and "pain" in the psychological scale were significantly lower (better) in T group than P group. 5) In Difmax values, all scales except respiratory condition related scale showed lower levels (better) in T group and the total score of 13 items, the face scale and the physiological and psychological scales showed significantly lower levels than P group. 6) Difmax values in each item belonging to the physiological and psychological scales showed lower levels in the T group, while "appetite" and "vomiting" in the physiological scale and "sleep" in the psychological scale showed significantly lower levels (better) than those of the P group. 7) In the stratified analysis performed for patients without nausea and vomiting on the 1st day of chemotherapy, there was no significance in AUC levels of all items in both groups. In patients with nausea and vomiting on the 1st day, the total score of 13 items, the face scale, the physiological and the psychological scales in the T group were significantly better than in the P group. 8) It was suggested that the anti-emetic efficacy of tropisetron for delayed nausea and vomiting might reduce the undesirable influence of chemotherapy on QOL, especially on the physiological and the psychological effects. These results suggested that this new questionnaire is applicable for evaluation of the utility of anti-emetics in patients in cancer chemotherapy, and that tropisetron capsules could reduce the decrease of QOL in delayed nausea and vomiting induced by chemotherapy.  相似文献   
998.
Crosslinking of partially neutralized carboxyl-terminated liquid rubbers (PNCTLR) with bisepoxide and anhydride was investigated by the PNCTLR–bisepoxide–anhydride reactions. The PNCTLR were prepared, by the partial neutralization with MgO and CaO, from a polymer of butadiene (Hycar CTB 2000X162) and a copolymer of butadiene–acrylonitrile (Hyca? CTBN 1300X8). As the bisepoxide, bisphenol-A diglycidyl ether was used, and hexahydrophthalic anhydride was the anhydride used. It was found that the metal carboxylate groups of PNCTLR catalyze the crosslinking reactions, and, further, the Mg carboxylate group showed higher catalytic activities than the Ca carboxylate group. As for the physical properties of the cured rubbers obtained, the rubbers containing Mg showed higher tensile strength and Shore A hardness than those containing Ca. In addition, the CTBN-series cured rubbers showed better physical properties than those of the CTB-series, because of a polarity effect of nitrile groups in the former rubbers. Resistances to water and chemical attack, thermal behavior, and stress relaxation are also discussed.  相似文献   
999.
(R)-3-Dodecanoyl-4-phosphatidylcholino-hydroxymethyl-2-oxazolidino ne (7), which is a new glycerophospholipid analog, was synthesized starting from (S)-glycidol through a 4-alkylsilyoxymethyl derivative and N-acyl-4-hydroxymethyl derivative. The cyclic amide analog 7 showed strong inhibitory activity toward both Group I and II PLA25, but the inhibitory potency of 7 was slightly weaker than that of the linear amide analog (R)-1, which had been developed by de Haas et al. (Biochem. Biophys. Acta 1990, 1043, 67). The interactions of 7 with human secretory PLA2 was investigated by computer modeling in comparison with those of the linear amide analog 1. The results of the computer modeling were very compatible with those of the inhibitory activities toward PLA2S, and the both results showed that the binding mode of the oxazolidinone analog 7 was very similar to that of the genuine substrate and was different from that of the linear amide analog 1.  相似文献   
1000.
We investigated effects of various tea infusions on mast cell activation using mouse mast cells. Among various tea extracts, infusions from cultivar 'Benihomare' and Taiwan lineage strongly inhibited histamine release after Fc epsilon RI cross-linking. Among three types of tea (from cultivar 'Benihomare'), extract from oolong tea or black tea inhibited histamine release more strongly than green tea extract. Furthermore, 'Benihomare' oolong tea extract suppressed tyrosine phosphorylation of cellular proteins after Fc epsilon RI cross-linking, but polyvinyl polypyrrolidone treatment of the extract to remove phenolic compounds, weakened the suppressive effect.  相似文献   
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