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1.
Cells of the terrestrial plant species bromegrass (Bromus inermis L.) are not naturally adapted to withstand the hydrostatic pressures encountered in aquatic environments. However, after treatment with the natural plant growth hormone abscisic acid (75 micromolar), bromegrass cells survived a hydrostatic pressure of 101.3 megapascals, approximating the limits of ocean depth (10,860 m). The increased resistance to hydrostatic pressure from 1 to 7 days of abscisic acid treatment paralleled the induced elevation of cell tolerance to freezing stress. 相似文献
2.
Naoko Minatani Mina Waraya Keishi Yamashita Mariko Kikuchi Hideki Ushiku Ken Kojo Akira Ema Hiroshi Nishimiya Yoshimasa Kosaka Hiroshi Katoh Norihiko Sengoku Hirokazu Tanino David Sidransky Masahiko Watanabe 《PloS one》2016,11(1)
Using pharmacological unmasking microarray, we identified promoter DNA methylation of cysteine dioxygenase 1 (CDO1) gene in human cancer. In this study, we assessed the clinicopathological significance of CDO1 methylation in primary breast cancer (BC) with no prior chemotherapy. The CDO1 DNA methylation was quantified by TaqMan methylation specific PCR (Q-MSP) in 7 BC cell lines and 172 primary BC patients with no prior chemotherapy. Promoter DNA of the CDO1 gene was hypermethylated in 6 BC cell lines except SK-BR3, and CDO1 gene expression was all silenced at mRNA level in the 7 BC cell lines. Quantification of CDO1 methylation was developed using Q-MSP, and assessed in primary BC. Among the clinicopathologic factors, CDO1 methylation level was not statistically significantly associated with any prognostic factors. The log-rank plot analysis elucidated that the higher methylation the tumors harbored, the poorer prognosis the patients exhibited. Using the median value of 58.0 as a cut-off one, disease specific survival in BC patients with CDO1 hypermethylation showed significantly poorer prognosis than those with hypomethylation (p = 0.004). Multivariate Cox proportional hazards model identified that CDO1 hypermethylation was prognostic factor as well as Ki-67 and hormone receptor status. The most intriguingly, CDO1 hypermethylation was of robust prognostic relevance in triple negative BC (p = 0.007). Promoter DNA methylation of CDO1 gene was robust prognostic indicator in primary BC patients with no prior chemotherapy. Prognostic relevance of the CDO1 promoter DNA methylation is worthy of being paid attention in triple negative BC cancer. 相似文献
3.
4.
A new synthetic methodology for aldoses and aldonitols was developed in which two stereospecific epoxide-opening reactions with double inversion of the configuration, i.e., the ring-opening reaction of epoxy sulfides with phenylboronic acid and the stereospecific interconversion of trans- and cis-epoxy sulfides, were designed as the key steps. The synthetic potential of the new methodology was exemplified by the highly stereoselective synthesis of two pentose-derived sugars, arabitol and adonitol (ribitol). 相似文献
5.
Citrus limonoids obacunone and limonin inhibit azoxymethane-induced colon carcinogenesis in rats 总被引:2,自引:0,他引:2
Tanaka T Kohno H Tsukio Y Honjo S Tanino M Miyake M Wada K 《BioFactors (Oxford, England)》2000,13(1-4):213-218
Obacunone and limonin are bitter limonoids in citrus. Their modifying effects on the development of aberrant crypt foci (ACF), the activity of detoxification enzymes, glutathione S-transferase (GST) and quinone reductase (QR), and cell proliferation activity were investigated in male F344 rats treated with azoxymethane (AOM). Obacunone and limonin were administered in the diet, during the initiation (for 4 weeks) or postinitiation phase (for 4 weeks) of AOM-induced tumorigenesis. Feeding of obacunone and limonin (0.02% or 0.05%) caused significant reduction (55-65% by "initiation" feeding and 28-42% by "postinitiation" feeding) in the yield of ACF. The ability to reduce the proliferating cell nuclear antigen-labeling index in crypts and correlated well with the prevention of ACF. In a subsequent long-term experiment (38 weeks), in which rats were initiated with AOM and fed 0.05% obacunone or 0.05% limonin during the initiation or post-initiation phase, both compounds in diet caused significant reduction (65%-92% inhibition) in the incidence of colonic adenocarcinoma. Thus, citrus bitter limonoids obacunone and limonin possess chemopreventive effects on chemically induced rat colon carcinogenesis. 相似文献
6.
Tamalampudi S Talukder MM Hama S Tanino T Suzuki Y Kondo A Fukuda H 《Applied microbiology and biotechnology》2007,75(2):387-395
To expand the industrial applications of Candida antarctica lipase B (CALB), we developed Aspergillus oryzae whole-cell biocatalyst expressing the lipase-encoding gene from C. antarctica. A. oryzae niaD300, which was derived from the wild type strain RIB40, was used as the host strain. The CALB gene was isolated from
C. antarctica CBS6678 and expression plasmids were constructed with and without secretion signal peptide. The lipase gene was expressed
under the control of improved glaA and pNo-8142 promoters of plasmids pNGA142 and pNAN8142, respectively. The Southern blot
analysis demonstrated the successful integration of the CALB gene in the genome of A. oryzae. To determine the role of signal peptide, the expression plasmids were constructed with homologous and heterologous secretion
signal sequences of triacylglycerol lipase gene (tglA) from A. oryzae and lipase B (CALB) from C. antarctica, respectively. The C-terminal FLAG tag does not alter the catalytic properties of the lipase enzyme and Western blotting
analysis using anti-FLAG antibodies demonstrated the presence of cell wall and membrane bound lipase responsible for the biocatalytic
activity of the whole-cell biocatalyst. The resultant recombinant A. oryzae was immobilized within biomass support particles (BSPs) made of polyurethane foam (PUF) and the BSPs were successfully used
for the hydrolysis of para-nitrophenol butyrate (p-NPB) and for the optical resolution of (RS)-1-phenyl ethanol by enantioselective transesterification with vinyl acetate as acyl donor. 相似文献
7.
Ponnada Suresh Kumar KK Pulicherla Mrinmoy Ghosh Anmol Kumar KRS Sambasiva Rao 《Bioinformation》2011,6(8):311-314
Enzymes from psychrophiles catalyze the reactions at low temperatures with higher specific activity. Among all the psychrophilic enzymes produced, cold active
β-galactosidase from marine psychrophiles revalorizes a new arena in numerous areas at industrial level. The hydrolysis of lactose in to glucose and galactose by
cold active β-galactosidase offers a new promising approach in removal of lactose from milk to overcome the problem of lactose intolerance. Herein we propose, a
3D structure of cold active β-galactosidase enzyme sourced from Pseudoalteromonas haloplanktis by using Modeler 9v8 and best model was developed having
88% of favourable region in ramachandran plot. Modelling was followed by docking studies with the help of Auto dock 4.0 against the three substrates lactose,
ONPG and PNPG. In addition, comparative docking studies were also performed for the 3D model of psychrophilic β-galactosidase with mesophilic and
thermophilic enzymes. Docking studies revealed that binding affinity of enzyme towards the three different substrates is more for psychrophilic enzyme when
compared with mesophilic and thermophilic enzymes. It indicates that the enzyme has high specific activity at low temperature when compared with mesophilic
and thermophilic enzymes. 相似文献
8.
Tree seasonality in a warming climate 总被引:1,自引:0,他引:1
Climate warming has increased researchers' interest in plant phenology and its modelling. Although the main focus is on projections of accelerated springtime phenological events, also a further extension of the growing season by delayed growth cessation is often projected. However, ecophysiological studies indicate that, for boreal and temperate trees, such generalisations are precluded owing to differential climatic conditions and inter- and intraspecific genetic differences. The annual cycle of these trees is an integrated system, where one phase affects subsequent phases, resulting in delayed impacts, which are only partially addressed in current ecophysiological models. Here, we outline an updated integrated conceptual model of the annual cycle by identifying ecophysiological phenomena that are particularly significant under climate warming. 相似文献
9.
10.
Takahiro Okazaki Chiemi Nakanishi-Ito Naohiro Seo Takae Tanino Masafumi Takiguchi Kohji Egawa 《Cancer immunology, immunotherapy : CII》1993,36(2):83-88
Tumor-specific expression of Qa-2k antigen coded by the Q5k gene on various mouse tumor cells and immunological response of the host mice to the antigen have been demonstrated [Seo et al. (1992) J Exp Med 175: 547; Tanino et al. (1992) Cancer Immunol Immunother 35: 230]. The possibility was examined that Qa-2 antigen is one of the recognition target molecules of immunopotentiator-induced, H-2-nonrestricted tumoricidal lymphocytes of Qa-2– mice. Lymphocytes stimulated in vivo withP. acnes or culture-induced anomalous killers of B6.K1 mice did not exhibit significant in vitro cytotoxicity against B6.K1 lymphoblasts but lysed their Qa-2,3-congenic counterpart B6 lymphoblasts. To demonstrate the Qa-2 specificity of such cytotoxic cells more precisely, an L cell transformant clone (LQ7b/Kb), which expressed the 1 and 2 domains of the Qa-2 antigen (Q7b gene product), was generated by transfecting a cloned plasmid DNA containing a hybrid gene constructed from the 5 half of the Q7b gene and the 3 half of the H-2Kb gene (pQ7b/Kb). Using LQ7b/Kb cells as the target cells and the nylon-wool-nonadherent fraction of lymphocytes fromP. acnes-stimulated (C3H/He × B6.K1)F1 mice (H-2k, Qa-2–) as the effector cells of the in vitro cytotoxicity reaction, the presence of cytotoxic cells that recognize the 1/2 region of the Q7b gene product was demonstrated. The cytotoxic activity was dependent on T cells bearing T cell receptors of the / type (TCR/). The (C3H/He × B6.K1)F1 effector cells, as well as the B6.K1 effector cells also lysed BW5147 lymphoma cells (Qa-2k+) derived from AKR mice (Qa-2–, H-2k). By target-competition experiments it was shown that some of the effector cells lytic to BW5147 were identical to those that lysed LQ7b/Kb. Therefore some of the tumoricidal cells induced by the immunopotentiator interact with the target tumor cells through recognition of the 1/2 region of the Qa-2k tumor antigen by TCR/. 相似文献