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31.
Sato H Kato R Isogai Y Saka G Ohtsuki M Taketomi Y Yamamoto K Tsutsumi K Yamada J Masuda S Ishikawa Y Ishii T Kobayashi T Ikeda K Taguchi R Hatakeyama S Hara S Kudo I Itabe H Murakami M 《The Journal of biological chemistry》2008,283(48):33483-33497
Among the many mammalian secreted phospholipase A2 (sPLA2) enzymes, PLA2G3 (group III secreted phospholipase A2) is unique in that it possesses unusual N- and C-terminal domains and in that its central sPLA2 domain is homologous to bee venom PLA2 rather than to other mammalian sPLA2s. To elucidate the in vivo actions of this atypical sPLA2, we generated transgenic (Tg) mice overexpressing human PLA2G3. Despite marked increases in PLA2 activity and mature 18-kDa PLA2G3 protein in the circulation and tissues, PLA2G3 Tg mice displayed no apparent abnormality up to 9 months of age. However, alterations in plasma lipoproteins were observed in PLA2G3 Tg mice compared with control mice. In vitro incubation of low density (LDL) and high density (HDL) lipoproteins with several sPLA2s showed that phosphatidylcholine was efficiently converted to lysophosphatidylcholine by PLA2G3 as well as by PLA2G5 and PLA2G10, to a lesser extent by PLA2G2F, and only minimally by PLA2G2A and PLA2G2E. PLA2G3-modified LDL, like PLA2G5- or PLA2G10-treated LDL, facilitated the formation of foam cells from macrophages ex vivo. Accumulation of PLA2G3 was detected in the atherosclerotic lesions of humans and apoE-deficient mice. Furthermore, following an atherogenic diet, aortic atherosclerotic lesions were more severe in PLA2G3 Tg mice than in control mice on the apoE-null background, in combination with elevated plasma lysophosphatidylcholine and thromboxane A2 levels. These results collectively suggest a potential functional link between PLA2G3 and atherosclerosis, as has recently been proposed for PLA2G5 and PLA2G10. 相似文献
32.
33.
Ji Yuhao Yuki Ryuji Kentarou Matsumura Takahisa Miyatake 《Ethology : formerly Zeitschrift fur Tierpsychologie》2021,127(1):45-49
Biogenic amines such as dopamine are physiologically neuroactive substances that affect behavioral and physiological traits in invertebrates, and it has long been known that these substances affect mating behavior in insects. Caffeine is a dopamine activator and thus enhances dopamine receptor activity. However, the effects of caffeine intake on insect mating behavior have been largely unexplored. Therefore, we examined the effect of caffeine on mating behavior in the red flour beetle Tribolium castaneum. Caffeine, which activates dopamine, affected the mating behavior of T. castaneum males. Males who orally ingested caffeine courted faster than males who did not, resulting in faster mounting of females and less time to a male's external aedeagus protrusion. However, the present results showed no difference in sperm precedence measured as a P2 value between males fed caffeine and males not fed caffeine. We discuss the effects of caffeine on insect mating and the possibility that caffeine consumption may cause males to mate with more females in the laboratory. 相似文献
34.
Free radicals generated by chemicals can cause sequence-specific DNA damage and play important roles in mutagenesis and carcinogenesis. Carbamoyl group (CONH 2 ) and its derived groups (CONR 2 ) occur as natural products and synthetic chemical compounds. We have investigated the DNA damage by carbamoyl radicals · (CONH 2 ), one of carbon-centered radicals. Electron spin resonance (ESR) spectroscopic study has demonstrated that carbamoyl radicals were generated from formamide by treatment with H 2 O 2 plus Cu(II), and from azodicarbonamide by treatment with Cu(II). We have investigated sequence specificity of DNA damage induced by carbamoyl radicals using 32 P-labeled DNA fragments obtained from the human c-Ha- ras -1 and p 53 genes. Treatment of double-stranded DNA with carbamoyl radicals induced an alteration of guanine residues, and subsequent treatment with piperidine or Fpg protein led to chain cleavages at 5'-G of GG and GGG sequences. Carbamoyl radicals enhanced Cu(II)/H 2 O 2 -mediated formation of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) in double-stranded DNA more efficiently than that in single-stranded DNA. These results shows that carbamoyl radicals specifically induce hydroxylation of deoxyguanosine at 5' site of GG and GGG sequences in double-stranded DNA. 相似文献
35.
The flower bugs or minute pirate bugs, Anthocoridae sensu lato, are represented by 12 genera and 24 species in the Korean Peninsula. The present catalog includes three newly recorded species to the fauna: Anthocoris confusus Reuter, Bilia japonica Carayon et Miyamoto, and Montandoniola pictipennis (Esaki). Distributional data and bibliographical references of each taxon are included. Biological notes (habitats, prey types, etc.) and diagnoses based on the local materials of the Korean Peninsula are also presented for the field of applied entomology. 相似文献
36.
Purpose
To assess the time course of optical quality and intraocular scattering in relation to visual acuity after femtosecond lenticule extraction (FLEx) for the correction of myopia.Methods
This study evaluated 36 eyes of 36 patients with spherical equivalents of −4.38±1.53 D [mean ± standard deviation] who underwent FLEx. Before surgery, and 1 week and 1, 3 and 6 months after surgery, we assessed the modulation transfer function (MTF) cutoff frequency, Strehl ratio, objective scattering index (OSI), and OQAS values (OVs), using a double-pass instrument. We also investigated the relationship of the OSI with corrected distance visual acuity (CDVA) preoperatively and postoperatively.Results
The mean changes in MTF cutoff frequency, Strehl ratio, OSI, OV100%, OV20%, and OV9% preoperatively and 6 months postoperatively were −5.51±15.01, −0.03±0.07, 0.35±0.83, −0.17±0.48, −0.14±0.38, and −0.09±0.22, respectively. We found no significant preoperative correlation between the OSI and logMAR CDVA (Spearman rank correlation coefficient r = 0.068, p = 0.69), and modest, but significant correlations 1 week and 1, 3, and 6 months postoperatively (r = 0.572, r = 0.562, r = 0.542, r = 0.540, p<0.001, respectively).Conclusions
FLEx induced a transient decrease in optical quality in association with an increase in intraocular scattering in the early postoperative period, possibly due to mild interface haze formation, but gradually recovered with time. It is suggested that this transient degradation in optical quality related to an increase in the intraocular scattering may result in a slight delay of CDVA recovery in the early postoperative period. 相似文献37.
Seunghee Seo Kanako Takayama Kyosuke Uno Kazutaka Ohi Ryota Hashimoto Daisuke Nishizawa Kazutaka Ikeda Norio Ozaki Toshitaka Nabeshima Yoshiaki Miyamoto Atsumi Nitta 《PloS one》2013,8(10)
The single nucleotide polymorphism (SNP) rs13438494 in intron 24 of PCLO was significantly associated with bipolar disorder in a meta-analysis of genome-wide association studies. In this study, we performed functional minigene analysis and bioinformatics prediction of splicing regulatory sequences to characterize the deep intronic SNP rs13438494. We constructed minigenes with A and C alleles containing exon 24, intron 24, and exon 25 of PCLO to assess the genetic effect of rs13438494 on splicing. We found that the C allele of rs13438494 reduces the splicing efficiency of the PCLO minigene. In addition, prediction analysis of enhancer/silencer motifs using the Human Splice Finder web tool indicated that rs13438494 induces the abrogation or creation of such binding sites. Our results indicate that rs13438494 alters splicing efficiency by creating or disrupting a splicing motif, which functions by binding of splicing regulatory proteins, and may ultimately result in bipolar disorder in affected people. 相似文献
38.
Daisuke Hayasaka Kenji Shirai Kotaro Aoki Noriyo Nagata Dash Sima Simantini Kazutaka Kitaura Yuki Takamatsu Ernest Gould Ryuji Suzuki Kouichi Morita 《PloS one》2013,8(8)
Japanese encephalitis virus (JEV) causes acute central nervous system (CNS) disease in humans, in whom the clinical symptoms vary from febrile illness to meningitis and encephalitis. However, the mechanism of severe encephalitis has not been fully elucidated. In this study, using a mouse model, we investigated the pathogenetic mechanisms that correlate with fatal JEV infection. Following extraneural infection with the JaOArS982 strain of JEV, infected mice exhibited clinical signs ranging from mild to fatal outcome. Comparison of the pathogenetic response between severe and mild cases of JaOArS982-infected mice revealed increased levels of TNF-α in the brains of severe cases. However, unexpectedly, the mortality rate of TNF-α KO mice was significantly increased compared with that of WT mice, indicating that TNF-α plays a protective role against fatal infection. Interestingly, there were no significant differences of viral load in the CNS between WT and TNF-α KO mice. However, exaggerated inflammatory responses were observed in the CNS of TNF-α KO mice. Although these observations were also obtained in IL-10 KO mice, the mortality and enhanced inflammatory responses were more pronounced in TNF-α KO mice. Our findings therefore provide the first evidence that TNF-α has an immunoregulatory effect on pro-inflammatory cytokines in the CNS during JEV infection and consequently protects the animals from fatal disease. Thus, we propose that the increased level of TNF-α in severe cases was the result of severe disease, and secondly that immunopathological effects contribute to severe neuronal degeneration resulting in fatal disease. In future, further elucidation of the immunoregulatory mechanism of TNF-α will be an important priority to enable the development of effective treatment strategies for Japanese encephalitis. 相似文献
39.
Kazuyuki Nakamura Hirofumi Kodera Tenpei Akita Masaaki Shiina Mitsuhiro Kato Hideki Hoshino Hiroshi Terashima Hitoshi Osaka Shinichi Nakamura Jun Tohyama Tatsuro Kumada Tomonori Furukawa Satomi Iwata Takashi Shiihara Masaya Kubota Satoko Miyatake Eriko Koshimizu Kiyomi Nishiyama Mitsuko Nakashima Yoshinori Tsurusaki Noriko Miyake Kiyoshi Hayasaka Kazuhiro Ogata Atsuo Fukuda Naomichi Matsumoto Hirotomo Saitsu 《American journal of human genetics》2013
40.
Mayumi Hadano Kenlo Nishida Nasahara Takeshi Motohka Hibiki Muraoka Noda Kazutaka Murakami Masahiro Hosaka 《Ecology and evolution》2013,3(6):1798-1807
Reports indicate that leaf onset (leaf flush) of deciduous trees in cool‐temperate ecosystems is occurring earlier in the spring in response to global warming. In this study, we created two types of phenology models, one driven only by warmth (spring warming [SW] model) and another driven by both warmth and winter chilling (parallel chill [PC] model), to predict such phenomena in the Japanese Islands at high spatial resolution (500 m). We calibrated these models using leaf onset dates derived from satellite data (Terra/MODIS) and in situ temperature data derived from a dense network of ground stations Automated Meteorological Data Acquisition System. We ran the model using future climate predictions created by the Japanese Meteorological Agency's MRI‐AGCM3.1S model. In comparison to the first decade of the 2000s, our results predict that the date of leaf onset in the 2030s will advance by an average of 12 days under the SW model and 7 days under the PC model throughout the study area. The date of onset in the 2090s will advance by 26 days under the SW model and by 15 days under the PC model. The greatest impact will occur on Hokkaido (the northernmost island) and in the central mountains. 相似文献