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231.
Senpuku H Tada A Nakao R Yonezawa H Yoneda S Yoshihara A Miyazaki H 《FEMS immunology and medical microbiology》2007,49(1):84-90
The amino acid residues 361-386 of Streptococcus mutans PAc includes an important region associated with the interaction between S. mutans and salivary components. We investigated the relationships between levels of the anti-PAc (361-386) peptide antibody (PPA) in saliva and periodontal status in 281 elderly subjects (mean age 77 years; 118 females, 163 males) by assessing dental calculus (CA), attachment loss (AL), pocket depth (PD), bleeding on probing (BOP) and various blood parameters. Enzyme-linked immunosorbent assay results revealed that subjects with a PPA level of greater than 0.1 (PPA detected group) showed a lower average value for number of sites with more than 6 mm of AL/6 points x 100/tooth (rAL6) than those with a PPA level of less than 0.1 (PPA not detected group). Furthermore, average values for rAL6 were significantly lower in the PPA detected group, and BOP, AL and rAL6 correlated positively and significantly with the percentage of eosinophils present in leukocytes in female subjects in both groups. PPA level had a negative correlation with percentages of basophils and eosinophils. The results indicate that systemic increases in numbers of eosinophils and basophils are associated with the development of periodontal diseases, while PPA level may be a useful indicator of periodontal status. 相似文献
232.
Improved immunocytochemical detection of daunomycin 总被引:3,自引:3,他引:0
Improved immunocytochemical (ICC) detection of the anthracycline anticancer antibiotic daunomycin (DM) has been achieved by
use of hydrogen peroxide oxidation prior to ICC staining for DM. The new method greatly enhanced the localization of DM accumulation
in cardiac, smooth and skeletal muscle of rats after a single i.v. dose of the drug. DM accumulated in the nuclei as well
as in the sarcoplasm, where it occurred in the form of small granules, which were particularly evident in cardiac muscle cells.
The distribution of the granules coincided with that of mitochondria. Uptake of DM in nuclei and mitochondria of heart muscle
cells may help to improve our understanding of the cardiac toxicity of DM and related anthracyclin antibiotics. A number of
ELISA tests were carried out in order to elucidate the mechanims of H2O2−assisted antigen retrieval. A possible mechanism is that DM is reduced and converted to its semiquinone and/or hydroquinone
derivative in vivo. Oxidation by hydrogen peroxide acts to convert these derivatives back to the native antigen. The improved
ICC methodology using oxidation to recreate native antigens from reduced metabolites may be helpful also with respect to the
localization of other drugs. 相似文献
233.
Pack SP Doi A Nonogawa M Kamisetty NK Devarayapalli KC Kodaki T Makino K 《Nucleosides, nucleotides & nucleic acids》2007,26(10-12):1589-1593
Oxanine (Oxa), which is one of the major products generated from guanine by nitrosative oxidation and is as long-lived as Gua in DNA, has been thought to be one of the major causes for NO-induced DNA damage. In the present study, using several synthetic Oxa-containing oligodeoxynucleotides, biophysical stability and enzymatic recognition of Oxa was investigated in DNA strands. It was found that Oxa did not mediate marked distortion in the whole DNA structure although Oxa pairing with 4 normal bases decreased thermal stability of the DNA duplexes compared to Gua:Cyt base pair. Regarding the responses of the DNA-relevant enzymes to Oxa, it was determined that Oxa was recognized as Gua except that DNA polymerases incorporated Thy as well as Cyt opposite Oxa. These results imply that Oxa tends to behave as a kind of naturally occurring base, Gua and therefore, would be involved in the genotoxic and cytotoxic threats of NO in cellular system. 相似文献
234.
Rohini Bhat Anil Kumar Singh Muntazir Mushtaq Romesh Kumar Salgotra Manmohan Sharma Basharat Ahmad Bhat Umer Basu Ibrahim Al-Ashkar Mohammad Anwar Hossain Akihiro Ueda Ayman El Sabagh 《Phyton》2022,91(11):2439-2459
Identification of quantitative trait loci (QTLs) controlling yield and yield-related traits in rice was performed in
the F2 mapping population derived from parental rice genotypes DHMAS and K343. A total of 30 QTLs governing nine different traits were identified using the composite interval mapping (CIM) method. Four QTLs were
mapped for number of tillers per plant on chromosomes 1 (2 QTLs), 2 and 3; three QTLs for panicle number
per plant on chromosomes 1 (2 QTLs) and 3; four QTLs for plant height on chromosomes 2, 4, 5 and 6; one
QTL for spikelet density on chromosome 5; four QTLs for spikelet fertility percentage (SFP) on chromosomes
2, 3 and 5 (2 QTLs); two QTLs for grain length on chromosomes 1 and 8; three QTLs for grain width on chromosomes1, 3 and 8; three QTLs for 1000-grain weight (TGW) on chromosomes 1, 4 and 8 and six QTLs for yield
per plant (YPP) on chromosomes 2 (3 QTLs), 4, 6 and 8. Most of the QTLs were detected on chromosome 2, so
further studies on chromosome 2 could help unlock some new chapters of QTL for this cross of rice variety. Identified QTLs elucidating high phenotypic variance can be used for marker-assisted selection (MAS) breeding.
Further, the exploitation of information regarding molecular markers tightly linked to QTLs governing these traits
will facilitate future crop improvement strategies in rice. 相似文献
235.
Kunisawa Kazuo Shan Jiajing Lu Qiaohui Yang Yang Kosuge Aika Kurahashi Hitomi Saito Kuniaki Zou Libo Nabeshima Toshitaka Mouri Akihiro 《Neurochemical research》2022,47(9):2880-2889
Neurochemical Research - Major depressive disorder (MDD) is the most prevalent and serious psychiatric disease involving inflammation. Loureirin C and Xanthoceraside are extracts of dragon’s... 相似文献
236.
Akihiro Matsunaga Masamichi Takami Tarou Irié Kenji Mishima Katsunori Inagaki Ryutaro Kamijo 《Cytotechnology》2015,67(4):727-732
Sintered compounds prepared with β-tricalcium phosphate (β-TCP) are commonly used as biocompatible materials for bone regenerative medicine. Although implanted β-TCP is gradually replaced with new bone after resorption by osteoclasts, exactly how osteoclasts resorb β-TCP is not well understood. To elucidate this mechanism, we analyzed the structure of β-TCP discs on which mouse mature osteoclasts were cultured using scanning electron microscopy. We found that β-TCP was resorbed by mature osteoclasts on one side of each disc, as evidenced by the formation of multiple spine-like crystals at the exposed areas. Because osteoclasts secrete acid to resorb bone minerals, we mimicked this acidification by dipping β-TCP slices into HCl solution (pH 2.0). However, no spine-like crystals appeared even though the size of each β-TCP particle was reduced. On dentin slices, osteoclasts formed clear actin rings, which are cytoskeletal structures characteristic of bone-resorbing osteoclasts. No clear actin rings were observed in osteoclasts cultured on β-TCP slices, although small actin dots were observed. Analysis by transmission electron microscopy showed that osteoclasts attached to β-TCP particles. These results suggest that osteoclasts resorb β-TCP particles independently of clear actin ring formation. 相似文献
237.
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239.
Suzuki N Shiota T Watanabe F Haga N Murashi T Ohara T Matsuo K Oomori N Yari H Dohi K Inoue M Iguchi M Sentou J Wada T 《Bioorganic & medicinal chemistry letters》2011,21(6):1601-1606
A structure-activity relationship study of 4-anilinopyrimidines for dual EGFR/Her-2 inhibitor has resulted in the identification of 4-anilino-5-alkenyl or 5-alkynyl-6-methylpyrimidine derivatives that have exhibited effective inhibitory activity against both enzymes. The presence of 5-alkenyl or 5-alkynyl moiety bearing terminal hydrophilic group played important role for inhibition of these enzymes. Selected compounds in the series demonstrated some activity against Her-2 dependent cell line (BT474). 相似文献
240.
Ishimoto H Shibata M Myojin Y Ito H Sugimoto Y Tai A Hatano T 《Bioorganic & medicinal chemistry letters》2011,21(19):5901-5904
Urolithin A is a major metabolite produced by rats and humans after consumption of pomegranate juice or pure ellagitannin geraniin. In this study, we investigated the anti-inflammatory effect of urolithin A on carrageenan-induced paw edema in mice. The volume of paw edema was reduced at 1h after oral administration of urolithin A. In addition, plasma in treated mice exhibited significant oxygen radical antioxidant capacity (ORAC) scores with high plasma levels of the unconjugated form at 1h after oral administration of urolithin A. These results indicate strong associations among plasma urolithin A levels, the plasma ORAC scores, and anti-inflammatory effects and may help explain a mechanism by which ellagitannins confer protection against inflammatory diseases. 相似文献