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41.
Previous results indicated that the herpes simplex virus 1 (HSV-1) U(L)31 gene is necessary and sufficient for localization of the U(L)34 protein exclusively to the nuclear membrane of infected Hep2 cells. In the current studies, a bacterial artificial chromosome containing the entire HSV-1 strain F genome was used to construct a recombinant viral genome in which a gene encoding kanamycin resistance was inserted in place of 262 codons of the 306 codon U(L)31 open reading frame. The deletion virus produced virus titers approximately 10- to 50-fold lower in rabbit skin cells, more than 2000-fold lower in Vero cells, and more than 1500-fold lower in CV1 cells, compared to a virus bearing a restored U(L)31 gene. The replication of the U(L)31 deletion virus was restored on U(L)31-complementing cell lines derived either from rabbit skin cells or CV1 cells. Confocal microscopy indicated that the majority of U(L)34 protein localized aberrantly in the cytoplasm and nucleoplasm of Vero cells and CV1 cells, whereas U(L)34 protein localized at the nuclear membrane in rabbit skin cells, and U(L)31 complementing CV1 cells infected with the U(L)31 deletion virus. We conclude that rabbit skin cells encode a function that allows proper localization of U(L)34 protein to the nuclear membrane. We speculate that this function partially complements that of U(L)31 and may explain why U(L)31 is less critical for replication in rabbit skin cells as opposed to Vero and CV1 cells. 相似文献
42.
T Suganuma T Imai K Idaira S Konno H Hoshino A Okazawa M Adachi T Takahashi M Maeda A Tsuji 《Arerugī》1991,40(5):529-537
We examined the effect of AH 21-132, which has been reported to relax airway smooth muscle and inhibit platelet activating factor (PAF)-induced airway hyperreactivity, on ozone-induced airway hyperresponsiveness (AHR) with airway inflammation in dogs. Airway responsiveness (AR) to methacholine was measured by modified Astograph (7 Hz oscillation method) before and after ozone exposure, and the numbers of neutrophils in the peripheral blood and total cell counts, differential cell counts and TXB2 in BALF were measured before and after ozone exposure. Ozone exposure was carried out for 2 hr at an ozone level of 3.46 +/- 0.10 ppm (mean +/- SE). There was a significant increase in AR to methacholine after ozone exposure (p less than 0.01), and the numbers of neutrophils in the peripheral blood and the total cell and neutrophil counts in BALF increased significantly (p less than 0.05). Pretreatment with AH 21-132 at an oral dose of 20 mg/kg significantly prevented the ozone-induced AHR to methacholine (p less than 0.01), and also inhibited the increase of neutrophil counts in the peripheral blood, and the total cell counts and the neutrophil counts in BALF after ozone exposure. There was no significant change in the levels of TXB2 in BALF before and after ozone exposure. In dogs not exposed to ozone, AR to methacholine and respiratory resistance to methacholine significantly decreased after administration of AH 21-132 at an oral dose of 20 mg/kg (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
43.
Takeshi Hariya Yuusuke Kobayashi Michiko Aihara Mamiko Ishiwa Michio Shibata Hideyuki Ichikawa Zenro Ikezawa 《Arerugī》2002,51(11):1113-1122
Atopic dermatitis (AD) has been clinically well-known to be frequently exacerbated by psychological and physiological stress. In this study, we examined effects of sedative odorant (modified valerian oil) inhalation on patients with AD. We investigated clinical scores, skin physiological parameters and psychological questionnaire (POMS) every 2 weeks. For first 2 weeks, we arranged non-inhalation period. Results for non-inhalation period were compared with these of 2- or 4-week inhalation. As results, sum of skin clinical scores significantly improved after odorant inhalation. Some patients improved for non-inhalation period, too. However, patients that had not improved for non-inhalation period significantly improved after odorant inhalation. Skin conductance and skin dryness/scaling score also improved after odorant inhalation without improving for non-inhalation period. Psychological parameter (POMS) also tended to improve after odorant inhalation. These results suggest that sedative odorants may be useful as a complementary therapy for AD through psychosomatic stress care. 相似文献
44.
Kiyoshi Tanabayashi Kaoru Takeuchi Michiko Hishiyama Akio Yamada Akira Sugiura 《Virus genes》1990,3(4):361-365
The nucleotide sequence of the gene encoding the matrix (M) protein of mumps virus (MuV), Miyahara strain, has been determined from several overlapping cDNA clones. The M protein mRNA is 1248 nucleotides in length, exclusive of the poly(A) tail, and codes for a protein of 375 amino acids (Mr41,556). Comparison of the deduced amino acid sequence of the M protein of the Miyahara strain with that of the SBL-1 strain revealed that the M proteins of both strains are highly conserved. A significantly lower rate of nucleotide differences conducive to amino acid differences in the M gene compared with other genes appeared to indicate the importance of the conserved primary structure of the M protein for its function.Requests for reprints should be addressed to Kiyoshi Tanabayashi, Department of Measles Virus, National Institute of Health, 4-7-1 Gakuen, Musashimurayama, Tokyo 190-12, Japan. 相似文献
45.
Administration of an aqueous methanol/water extract of the Oriental crude drug "maō" (Ephedra), EPHEDRA DISTACHYA herbs, caused transient hyperglycemia followed by long lasting hypoglycemia in mice. Activity-guided fractionation of the extract led to isolation of five glycans, ephedrans A, B, C, D and E, which exhibited significant hypoglycemic effects in normal and alloxan-induced hyperglycemic mice. 相似文献
46.
A water extract of the Oriental crude drug "shikon", LITHOSPERMUM ERYTHRORHIZON roots, remarkably diminished the plasma sugar level in mice. Fractionation of the extract by monitoring the activity yielded three glycans, lithospermans A, B and C. These glycans exerted marked hypoglycemic effects in normal and alloxan-induced hyperglycemic mice. 相似文献
47.
H Hikino C Konno M Takahashi M Murakami Y Kato M Karikura T Hayashi 《Planta medica》1986,52(3):168-171
Aqueous methanol/water extracts of the Oriental crude drug "sanyaku", DIOSCOREA JAPONICA and D. BATATAS rhizophors, notably lowered blood glucose concentration in mice. Activity-guided fractionation of the extract from D. JAPONICA afforded six glycans, dioscorans A, B, C, D, E, and F, which exhibited remarkable hypoglycemic effects in normal and alloxan-induced hyperglycemic mice. 相似文献
48.
Sonoo Mizuiri Yoshiko Nishizawa Toshiki Doi Kazuomi Yamashita Kenichiro Shigemoto Koji Usui Michiko Arita Takayuki Naito Shigehiro Doi Takao Masaki 《Renal failure》2021,43(1):371
ObjectiveA high coronary artery calcification score (CACS) may be associated with high mortality in patients undergoing hemodialysis (HD). Recently, effects of iron on vascular smooth muscle cell calcification have been described. We aimed to investigate the relationships between iron, CACS, and mortality in HD patients.MethodsWe studied 173 consecutive patients who were undergoing maintenance HD. Laboratory data and Agatston’s CACS were obtained at baseline for two groups of patients: those with CACS ≥400 (n = 109) and those with CACS <400 (n = 64). Logistic regression analyses for CACS ≥400 and Cox proportional hazard analyses for mortality were conducted.ResultsThe median (interquartile range) age and duration of dialysis of the participants were 67 (60–75) years and 73 (37–138) months, respectively. Serum iron (Fe) and transferrin saturation (TSAT) levels were significantly lower in participants with CACS ≥400 than in those with CACS <400, although the serum ferritin concentration did not differ between the groups. TSAT ≥21% was significantly associated with CACS ≥400 (odds ratio 0.46, p<0.05). TSAT ≥17%, Fe ≥63 µg/dL, and ferritin ≥200 ng/mL appear to protect against 5-year all-cause mortality in HD patients, independent of conventional risk factors of all-cause mortality (p < 0.05).ConclusionWe have identified associations between iron, CACS, and mortality in HD patients. Lower TSAT was found to be an independent predictor of CACS ≥400, and iron deficiency (low TSAT, iron, or ferritin) was a significant predictor of 5-year all-cause mortality in HD patients. 相似文献
49.
J Tamaoki N Sakai K Isono T Kanemura A Chiyotani F Yamauchi T Takizawa K Konno 《International archives of allergy and applied immunology》1991,95(2-3):169-173
We studied the effect of substance P (SP) on the electric properties of cultured canine tracheal epithelium and its possible modulation by neutral endopeptidase (NEP) by Ussing's short-circuited technique in vitro. Addition of SP (5 x 10(-6) M) to the mucosal side increased short-circuit current (SCC) from 5.1 +/- 0.9 to 10.3 +/- 2.2 microA/cm2 (mean +/- SE; p less than 0.01), which was accompanied by increases in transepithelial potential difference and conductance. The effect of the mucosal SP on SCC was dose-dependent, with the maximal increase from the baseline value being 5.8 +/- 1.0 microA/cm2 observed at 5 x 10(-5) M. The NEP inhibitor phosphoramidon (10(-5) M) did not affect these responses. On the other hand, SCC was not altered by the addition of SP to the submucosal side. However, it was increased dose-dependently in the presence of phosphoramidon (10(-5) M) but not in the presence of captopril, bestatin or leupeptin. This stimulatory effect of submucosal SP was abolished by furosemide, diphenylamine-2-carboxylate and Cl-free medium, but not by amiloride. These results suggest that SP may selectively stimulate Cl secretion across the airway epithelium and that this effect may be modulated by submucosal NEP. 相似文献
50.
- To elucidate whether K+ channels play a role in the action of epithelium-dependent bronchodilatation, we studied responses in human bronchial strips in the presence of indomethacin and NG-nitro-L-arginine methylester under isometric conditions, in vitro.
- Mechanical removal of the epithelium increased the contractile responses to acetylcholine; the pD2 values increased from 5.0±0.2 to 5.9±0.3 (P<0.001). This potentiation was abolished by iberiotoxin but not by apamin or glibenclamide.
- In cascade bioassay, application of the bathing medium from dispersed, bronchial epithelial cells to epithelium-denuded bronchial strips decreased acetylcholine-induced contraction by 44±6%. This effect was reduced to 10±3% (P<0.01) when the epithelial cells were pretreated with iberiotoxin, and to 4±1% (P<0.001) when the epithelial cells were incubated with Ca2+-free medium containing [1,2-bis (2) aminophenoxy] ethane N,N,N′,N′-tetraacetic acid-acetomethoxy ester.
- In contrast, the bronchodilator effect of the medium bathing epithelial cells was not altered by the direct addition of iberiotoxin to epithelium-denuded tissues.
- These results suggest that the Ca2+-activated K+ channel may play a role in the synthesis and/or release of smooth muscle relaxing factor, which is neither nitric oxide nor a cyclo-oxygenase product, from airway epithelial cells.