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1.
N. Yamada W. Murata Y. Yamaguchi K.-I. Fujita A. Ogita T. Tanaka 《Letters in applied microbiology》2021,72(4):390-398
Amphotericin B (AmB), a typical polyene macrolide antifungal agent, is widely used to treat systemic mycoses. In the present study, we show that the fungicidal activity of AmB was enhanced by benzyl isothiocyanate (BITC), a cruciferous plant-derived compound, in the budding yeast, Saccharomyces cerevisiae. In addition to forming a molecular complex with ergosterol present in fungal cell membranes to form K+-permeable ion channels, AmB has been recognized to mediate vacuolar membrane disruption resulting in lethal effects. BITC showed no effect on AmB-induced plasma membrane permeability; however, it amplified AmB-induced vacuolar membrane disruption in S. cerevisiae. Furthermore, the BITC-enhanced fungicidal effects of AmB significantly decreased cell viability due to the disruption of vacuoles in the pathogenic fungus Candida albicans. The application of the combinatorial antifungal effect of AmB and BITC may aid in dose reduction of AmB in clinical antifungal therapy and consequently decrease side effects in patients. These results also have significant implications for the development of vacuole-targeting chemotherapy against fungal infections. 相似文献
2.
Yuji Inaba Yoshio Tanaka Sukemitsu Ishii Tomiaki Morimoto Kunihiko Sato Tuneyoshi Omori Minoru Matumoto 《Microbiology and immunology》1970,14(5):351-360
Replication of Ibaraki virus was not inhibited by 5-iodo-2′-deoxyuridine, indicating that the virus is an RNA virus. The virus was resistant to ether, chloroform and deoxycholate, sensitive to trypsin, very labile at acidic pH but stable at pH 6.4 or higher, and was resistant to repeated freezing and thawing. The virus was readily inactivated at 56 C or higher, was fairly stable at 37 C, and very stable at 4 C, while it rapidly lost infectivity when stored frozen at —20 C. The virus was readily sedimented by centrifugation at 40 000Xg for 60 min. It readily passed through membrane filters of 200 mμ pore size, passed through 100 μfilters but only with some titer loss and did not through 50 mμ filters. In these tests, the bluetongue virus used as a control behaved in the same manner as Ibaraki virus. These findings provide additional evidence for the similarity of Ibaraki virus to bluetongue virus which had been previously demonstrated on the basis of seasonal incidence, symptomatology and pathology of the diseases caused by these viruses and the behavior of the viruses in cell cultures, embryonated eggs and laboratory animals. The present study, however, provided no evidence for any serological relation between these two viruses. More Information is needed to reach a final decision on the classification of Ibaraki virus, particularly regarding the morphology of the virion, the doublestrandedness of the viral RNA and other basic features. 相似文献
3.
Koichi Inoue Akiko Yamaguchi Megumi Wada Yoshihiro Yoshimura Tsunehisa Makino Hiroyuki Nakazawa 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,765(2):3469-126
Due to the ubiquity of epoxy resin compounds and their potential role in increasing the risk for reproductive dysfunction and cancer, the need for an assessment of human exposure is urgent. Therefore, we developed a method for measuring bisphenol A (BPA) and bisphenol A diglycidyl ether (BADGE) metabolites in human blood samples using high-performance liquid chromatography–electrospray ionization mass spectrometry (LC–MS). Human blood samples were processed using enzymatic deconjugation of the glucuronides followed by a novel sample preparation procedure using a solid-phase-cartridge column. This selective analytical method permits rapid detection of the metabolites, free BPA and a hydrolysis product of BADGE (BADGE-4OH) with detection limits in the low nanogram per milliliter range (0.1 ng ml−1 of BPA and 0.5 ng ml−1 of BADGE-4OH). The sample extraction was achieved by Oasis HLB column on gradient elution. The recoveries of BPA and BADGE-4OH added to human plasma samples were above 70.0% with a standard deviation of less than 5.0%. This selective, sensitive and accurate method will assist in elucidating potential associations between human exposure to epoxy-based compounds and adverse health effects. 相似文献
4.
5.
S Ikei M Ogawa T Beppu C Ohara K Sakamoto H Sameshima H Arakawa Y Yamaguchi T Yamanaka S Kudo 《Cytokine》1992,4(6):581-584
In an attempt to investigate the interaction between the changes of cytokines and acute phase reactants after transcatheter arterial chemoembolization therapy (TACE), the levels of interleukin 6 (IL-6), interleukin 8 (IL-8), C-reactive protein (CRP) and pancreatic secretory trypsin inhibitor (PSTI) in the blood of patients with unresectable hepatocellular carcinoma (HCC) were measured. Before the therapy, serum IL-6 and plasma IL-8 levels were detectable in 77.8% and 28.5%, respectively, of patients with HCC. Levels of serum IL-6 and plasma IL-8 increased after TACE and reached a peak on day 3 in all patients (18/18) and in 87.5% of patients (12/14), respectively. Both blood levels of IL-6 and IL-8 reached a peak earlier than those of CRP and PSTI did after the therapy. When the maximal values of IL-6 were compared with those of CRP and PSTI, there were significant positive correlations (r = 0.63, P < 0.01 and r = 0.81, P < 0.01, respectively). Similarly, comparisons of the maximal values of IL-8 with those of CRP and PSTI gave a significant correlation (r = 0.68, P < 0.01 and r = 0.67, P < 0.05, respectively). However, no significant correlation was found between the elevation of IL-6 and IL-8. 相似文献
6.
7.
Martin Bundi Mohammad Monir Shah Eric Odoyo Cyrus Kathiiko Ernest Wandera Gabriel Miring'u Sora Guyo Daniel Langat Kouichi Morita Yoshio Ichinose 《Microbiology and immunology》2019,63(9):350-358
Kenya is endemic for cholera with different waves of outbreaks having been documented since 1971. In recent years, new variants of Vibrio cholerae O1 have emerged and have replaced most of the traditional El Tor biotype globally. These strains also appear to have increased virulence, and it is important to describe and document their phenotypic and genotypic traits. This study characterized 146 V. cholerae O1 isolates from cholera outbreaks that occurred in Kenya between 1975 and 2017. Our study reports that the 1975–1984 strains had typical classical or El Tor biotype characters. New variants of V. cholerae O1 having traits of both classical and El Tor biotypes were observed from 2007 with all strains isolated between 2015 and 2017 being sensitive to polymyxin B and carrying both classical and El Tor type ctxB. All strains were resistant to Phage IV and harbored rstR, rtxC, hlyA, rtxA and tcpA genes specific for El Tor biotype indicating that the strains had an El Tor backbone. Pulsed field gel electrophoresis (PFGE) genotyping differentiated the isolates into 14 pulsotypes. The clustering also corresponded with the year of isolation signifying that the cholera outbreaks occurred as separate waves of different genetic fingerprints exhibiting different genotypic and phenotypic characteristics. The emergence and prevalence of V. cholerae O1 strains carrying El Tor type and classical type ctxB in Kenya are reported. These strains have replaced the typical El Tor biotype in Kenya and are potentially more virulent and easily transmitted within the population. 相似文献
8.
The activities of glutamic oxaloacetic transaminase and Ca++ ion-activated ATPase of muscle in the adult rats fed a protein-free diet for 8, 16 and 24 days were measured in order to clarify their metabolic responses with respect to reserve proteins. It was found that these enzyme activities, or presumably their enzyme proteins, decreased at the stage as early as the 8th day of protein depletion following the same pattern as seen in reserve proteins. Their responses, particularly those in unit activity, were somewhat different from each other. The metabolic significance of those responses was discussed in relation to protein nutrition. 相似文献
9.
J. Yamaguchi S. Itoh T. Saitoh A. Ikeda T. Tashiro Y. Nagato 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(1):32-38
β-Amylase deficiency in various cultivars of rice was examined at the molecular level. Using an antibody against β-amylase
purified from germinating seeds of rice, we were able to demonstrate the expression and organization of the β-amylase gene
in normal and deficient cultivars. Although β-amylase is a starch-hydrolyzing enzyme, as is α-amylase, the β-amylase protein/gene
is expressed differently from the α-amylase protein/gene; i.e. (1) β-amylase is synthesized only in aleurone cells, (2) the
enzyme production in the embryo-less half-seeds is not under hormonal control. We identified some cultivars of rice that are
deficient for β-amylase activity. We present new evidence that synthesis is blocked at the level of mRNA synthesis in the
deficient cultivars. The usefulness of β-amylase as a crop trait is also discussed.
Received: 8 May 1998 / Accepted: 5 June 1998 相似文献
10.