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Gonpachiro Yasuzumi Kook Jin Lee Hideko Fukui Masako Yoshida 《Cell and tissue research》1967,80(3):353-369
Summary Testes of the pond snail, Cipangopaludina malleata Reeve, were fixed in 1% osmium tetroxide, 3% permanganate, or 4% formaldehyde followed by 1% osmium tetroxide, each being buffered to pH 7.2 with Veronal-acetate or Sörensen's phosphate buffer. On the other hand, testes fixed with 4% formaldehyde adjusted to pH 7.2 with 0.075 M Na-cacodylate were incubated in Novikoff-Goldfischer medium for demonstrating thiamine pyrophosphatase, uridine or inosine diphosphatase, uridine monophosphatase or adenosine triphosphatase. The specimens incubated were postfixed in 1% osmium tetroxide buffered to pH 7.2 with Veronal-acetate buffer. Thin sections of the epoxy Epon resin-embedded tissue were stained either singly with saturated aqueous uranyl acetate or doubly with saturated aqueous uranyl acetate followed by lead citrate.In a concentric lamellar structure consisting of the granular endoplasmic reticulum in the cytoplasm of early atypical spermatids, disappearance of ribosomes attached to the outer surface of cisternae seems to have initiated at the central part of the structure, and the cisterna-attached ribosomes seem to participate in the formation of dense granules appearing in the vesicles representing the endoplasmic reticulum of atypical spermatids.The Golgi apparatus of the atypical spermatids in the advanced stages of development is composed of at least three different layers, the central part consisting of an amorphous material, the following lamellar and vesicular elements, and the peripheral fine vesicles.It has been assumed that the mechanism by which the nucleic acid, especially DNA is converted into the polysaccharide might be attributed to the function of the Golgi apparatus, because the transformation of dense granules into less dense granules as well as diphosphatase activities have been detected within the Golgi apparatus.This study was supported by Grant GM-8327-06 from the United States Public Health Service. 相似文献
155.
Isoprenoid quinones and fatty acids ofZoogloea 总被引:1,自引:0,他引:1
Akira Hiraishi Yong Kook Shin Junta Sugiyama Kazuo Komagata 《Antonie van Leeuwenhoek》1992,61(3):231-236
NineZoogloea strains including the type strain ofZ. ramigera (IAM 12136=ATCC 19544=N.C. Dondero 106) and newly isolated strains were investigated for isoprenoid quinone composition and whole-cell fatty acid profiles. Seven of the tested strains, having phenotypic properties typical ofZoogloea, were characterized by their production of both ubiquinone-8 and rhodoquinone-8 as major quinones, whereas the remaining two strains,Z. ramigera IAM 12669 (=K. Crabtree I-16-M) and IAM 12670 (=P.R. Dugan 115), formed ubiquinone-10 and ubiquinone-8, respectively, as the sole quinone. All rhodoquinone-producing strains contained palmitoleic acid and 3-hydroxy-decanoic acid as the major components of nonpolar and hydroxylated fatty acids, respectively. Marked differences were noted in the fatty acid composition between the strains with and without rhodoquinones. The chemotaxonomic data suggested that the rhodoquinonelacking strains should be excluded from the genusZoogloea. Since there have been no reliable taxonomic tools forZoogloea, rhodoquinone analysis may provide a new criterion of great promise for identifyingZoogloea strains. 相似文献
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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
159.
Jeong LS Lee HW Kim HO Jung JY Gunaga P Lee SK Lee EJ Chun MW Gao ZG Jacobson KA Moon HR 《Nucleosides, nucleotides & nucleic acids》2007,26(10-12):1565-1568
On the basis of potent and selective binding affinity of Cl-IB-MECA to the human A(3) adenosine receptor, its 4'-thioadenosine derivatives were efficiently synthesized starting from D-gulonic gamma-lactone. Among compounds tested, 2-chloro-N(6)-(3-iodobenzyl)- and 2-chloro-N(6)-methyl-4' -thioadenosine-5' -methyluronamides (7a and 7b) exhibited nanomolar range of binding affinity (K(i) = 0.38 nM and 0.28 nM, respectively) at the human A(3)AR. These compounds showed anti-growth effects on HL-60 leukemia cell, which resulted from the inhibition of Wnt signaling pathway. 相似文献
160.
Jeong LS Zhao LX Choi WJ Pal S Park YH Lee SK Chun MW Lee YB Ahn CH Moon HR 《Nucleosides, nucleotides & nucleic acids》2007,26(6-7):713-716
Synthesis of fluorocyclopentenyl pyrimidine nucleosides 6-9 was enantiopurely accomplished employing oxidative rearrangement, RCM reaction and electrophilic fluorination starting from d-ribose. Cytosine analog 8 was found to exhibit significant anticancer activity in various human tumor cell lines. 相似文献