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991.
Dong Jae Won Ki Seung Seong Cheol Ho Jang Jin Sil Lee Jung A Ko Hojae Bae 《Bioscience, biotechnology, and biochemistry》2019,83(5):942-951
Bioavailability and bone loss inhibitory effects of vitamin D2 derived from UV-irradiated shiitake mushroom were determined in vivo. The effect of the absence of ovaries on the bioavailability of vitamin D2 and bone structure was also investigated. Sham operated (sham) and ovariectomized (OVX) rats were divided in 3 groups according to their diets, i.e. control: only vitamin D-deficient diets; UV(X): vitamin D-deficient diets with non-irradiated mushroom powder; UV(O): vitamin D-deficient diets with irradiated mushroom powder. The obtained results showed that vitamin D2 from shiitake mushroom was able to increase bone mineral density and trabecular bone structure of femur bone as well as its bioavailability. The absence of estrogen induced adverse effects not only on bioavailability of vitamin D2 but also on trabecular bone. In conclusion, vitamin D2-fortified shiitake mushroom might help postmenopausal women increase vitamin D2 bioavailability and retard trabecular bone loss.
Abbreviations: OVX: ovariectomized; 25(OH)D: 25-hydroxyvitamin D; 1,25(OH)2D: 1,25-dihydroxyvitamin D; BMD: bone mineral density; micro-CT: micro computed tomography; RSM: response surface methodology; RP-HPLC: Reverse phase-high performance liquid chromatography; MS/MS: tandem mass spectrometry; E2: estradiol; NTx: N-terminal telopeptide of type I collagen; BV/TV: bone volume/total volume; BS/BV: bone surface/bone volume; Tb.Th: trabecular thickness; Tb.Sp: trabecular separation. 相似文献
992.
Taewoong Rho Soo‐Jung Choi Hyun Woo Kil Jaeyoung Ko Kee Dong Yoon 《Phytochemical analysis : PCA》2019,30(2):226-236
993.
Sox1 null lens fiber cells fail to elongate and have disrupted expression of gamma-crystallin. We have evaluated the expression of Sox1 and Pax6 proteins during critical stages of lens morphogenesis, with particular focus on fiber cell differentiation. While Pax6 and Sox1 are co-expressed during early stages of fiber cell differentiation, Sox1 up-regulation coincides temporally with the down-regulation of Pax6, and these proteins therefore display a striking inverse expression pattern in the lens fiber cell compartment. Furthermore, Pax6 is inappropriately expressed in the fiber cells of Sox1 null mice and the Pax6 target, alpha5 integrin, is simultaneously misexpressed. Finally, we demonstrate a genetic interaction between Sox1 and Pax6, as Sox1 heterozygosity partially rescues the diameter of Pax6(Sey) lenses by increasing the number of cells in the fiber cell compartment. 相似文献
994.
Tae‐Young Choi Jin‐Hwa Kim Dong Han Ko Cheol‐Hee Kim Jae‐Sung Hwang Soomi Ahn Sun Yeou Kim Chang‐Deok Kim Jeung‐Hoon Lee Tae‐Jin Yoon 《Pigment cell & melanoma research》2007,20(2):120-127
Although many hypo‐pigmenting agents are currently available, the demand for novel whitening agents is increasing, in part due to the weak effectiveness and unwanted side effects of currently available compounds. To screen for novel hypo‐pigmenting agents, many methodologies such as cell culture and enzymatic assays are routinely used. However, these models have disadvantages in terms of physiological and economic relevance. In this study, we validated zebrafish as a whole‐animal model for phenotype‐based screening of melanogenic inhibitors or stimulators. We used both the well‐known melanogenic inhibitors (1‐phenyl‐2‐thiourea, arbutin, kojic acid, 2‐mercaptobenzothiazole) and newly developed small molecule compounds (haginin, YT16i). All the tested compounds produced inhibitory effects on the pigmentation of zebrafish, most likely due to their inhibitory potential on tyrosinase activity. In simultaneous in vivo toxicity tests, a newly developed melanogenic inhibitor YT16i showed massive abnormalities in terms of deformed morphologies and cardiac function. Together, these results provide a rationale in screening and evaluating the putative melanogenic regulatory compounds. We suggest that the zebrafish system is a novel alternative to mammalian models, with several advantages including the rapidity, cost‐effectiveness, and physiological relevance. 相似文献
995.
Suk Weon Kim Sung Hee Ban Soon-Chun Jeong Hwa-Jee Chung Suk Min Ko Ook Joon Yoo Jang R. Liu 《Biotechnology and Bioprocess Engineering》2007,12(6):646-652
When whole cell extracts are subjected to proton nuclear magnetic resonance spectroscopy (1H NMR), metabolite profiles are generated that contain overlapping signals of the majority of compounds within the extract.
In order to determine whether pattern recognition based on the metabolite profiles of higher plants is able to genetically
discriminate between plants, we analyzed leaf samples of eight cultivars ofCatharanthus roseus by1H NMR. Hierarchical dendrograms, based on the principal component analysis of the1H NMR total, aliphatic carbohydrate and aromatic region data, revealed possible relationships between the cultivars. The dendrogram
based on the aromatic region data was in general agreement with the genetic relationships determined by conventional DNA fingerprinting
methods. Secologanin and polyphenols were assigned to the signals of the1H NMR spectra, and contributed most profoundly to the discrimination between cultivars. The overall results indicate that
the genetic relationships betweenC. roseus cultivars are reflected in the differences of the aromatic compounds in the leaves. 相似文献
996.
Byung-Hoon Kim Doman Kim Dong-Lyun Cho Sung-Hoon Lim So young Yoo Joong-ki Kook Yong ick Cho Seung-Ho Ohk Yeong-Mu Ko 《Biotechnology and Bioprocess Engineering》2007,12(2):136-139
Streptococcus mutans is one of the more significant pathogens involved in the development of dental caries in humans. The purpose of this research
was to design a TiO2-coated dental instrument and to determine the bactericidal effects of the instrument onS. mutants. TiO2 photocatalytic films were prepared by the low-pressure metal-organic chemical vapor deposition (LPMOCVD) method using titanium
tetraisopropoxide (TTIP) as precursor. The photocatalytic reaction was carried out on a TiO2-coated pyrex petri dish with an ultraviolet (UV) light emitting diode (LED) illuminator or a fluorescent lamp light source.
Our data indicates that the relative survival ratio ofS. mutans when plated onto TiO2 photocatalytic films and under exposure to UV-A light for 15 min was 0.01%. In addition, a fluorescent lamp light source
also had bactericidal effects on theS. mutans plated TiO2 photocatalytic films. These results indicate that TiO2-coated dental materials or devices may be useful in dental treatments for the prevention of carious or enamel demineralization. 相似文献
997.
Development of a general‐purpose method for cell purification using Cre/loxP‐mediated recombination 下载免费PDF全文
Shunsuke Kuroki Mika Akiyoshi Ko Ideguchi Satsuki Kitano Hitoshi Miyachi Michiko Hirose Nathan Mise Kuniya Abe Atsuo Ogura Makoto Tachibana 《Genesis (New York, N.Y. : 2000)》2015,53(6):387-393
A mammalian body is composed of more than 200 different types of cells. The purification of a certain cell type from tissues/organs enables a wide variety of studies. One popular cell purification method is immunological isolation, using antibodies against specific cell surface antigens. However, this is not a general‐purpose method, since suitable antigens have not been found in certain cell types, including embryonic gonadal somatic cells and Sertoli cells. To address this issue, we established a knock‐in mouse line, named R26 KI, designed to express the human cell surface antigen hCD271 through Cre/loxP‐mediated recombination. First, we used the R26 Kl mouse line to purify embryonic gonadal somatic cells. Gonadal somatic cells were purified from the R26 KI; Nr5a1‐Cre‐transgenic (tg) embryos almost equally as efficiently as from Nr5a1‐hCD271‐tg embryos. Second, we used the R26 KI mouse line to purify Sertoli cells successfully from R26 KI; Amh‐Cre‐tg testes. In summary, we propose that the R26 KI mouse line is a powerful tool for the purification of various cell types. genesis 53:387–393, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
998.
999.
Heterologous expression and characterization of endocellulase from the Japanese pine sawyer Monochamus saltuarius (MsGHF5) 下载免费PDF全文
Hyunjun Ko Hyuk‐Min Kwon Hyun‐Jin Ko Ji‐Hyeon Ryu Hwi‐Seung Song Yong Chul Park 《Entomological Research》2015,45(1):26-30
In this study, the endocellulase gene from Monochamus saltuarius (MsGHF5) was transformed into Escherichia coli (RosettaBlue(DE3)pLysS strain), and induced by IPTG. The molecular weight of recombinant MsGHF5 (rMsGHF5) was 78 kDa and was expressed as a fusion protein with maltose binding protein in pMAL‐c2 expression vector. Native‐PAGE was conducted with 0.1% carboxymethyl cellulose as a substrate, and the zymogenic bands were observed. The Michaelis constant and maximum velocity of rMsGHF5 were 0.199 mg/mL and 0.034 μmol/min/mL, respectively. The optimal condition for rMsGHF5 occurred at pH 5 and 30°C. Fe2+ and Mn2+ stimulated the activity of rMsGHF5 by 167 and 114% respectively, whereas Cu2+, Hg2+ and Zn2+ inhibited its activity. 相似文献
1000.
In vitro generation of functional dendritic cells differentiated from CD34 negative cells isolated from human umbilical cord blood 下载免费PDF全文