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991.
Yosiaki Itô Masako Nakamura Masaki Kondo Kazuyoshi Miyashita Kazuo Nakamura 《Population Ecology》1962,4(1):35-46
Summary As a part of serial study on population dynamics of the chestnut gall-wasp,Dryocosmus kuriphilus, analyses of the distribution of eggs, gall-cells and emergent holes were made from the statistical point of view. Many of
distributions of the eggs per bud could be described by the truncated Poisson, but some cases showed slight overdispersion
than expected by chance. Because of no linear increase of
with increasing
(expected mean for complete sample), however, the truncated negative binomial seemed to be not so available for whole series.
Distributions of the gall-cells and the emergent holes were, on the other hand, well described by the truncated Poisson distribution
when the observed frequency was calculated for respective trees. Negative-binomial tendency found in distributions from some
stations consisted of a certain number of trees would be resulted from mixture of Poisson populations with different means.
Random or slightly concentrated oviposition and random mortality within galls was thus supposed for future study unless the
proof favouring other distribution models would appear. 相似文献
992.
Mitsuhiro Wada Shinichi Nakamura Mamoru Tomita Mihoko N Nakashima Kenichiro Nakashima 《Luminescence》2005,20(3):210-215
A simultaneous semi-micro column HPLC method with fluorescence detection of abused drugs, such as 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA), amphetamine (AP) and methamphetamine (MP) in rat urine was examined by using 4-(N,N-dimethylaminosulphonyl)-7-fluoro-1,2,3-benzoxadiazole (DBD-F) as a labelling reagent and alpha-phenylethylamine as an internal standard (IS). A sample (50 microL) of rat urine was added to 5 microL IS and 100 microL 100 mmol/L borate buffer (pH 12) and extracted with 1.5 mL n-hexane. After evaporation, 50 microL 75 mmol/L borate buffer (pH 8.5) and 50 microL 20 mmol/L DBD-F in CH3CN were added to the residue and mixed well. The resultant solution was heated for 20 min at 80 degrees C and then cooled in an ice bath. A good separation of DBD-derivatives could be achieved within 45 min using a semi-micro ODS column with an eluent of CH3CN/CH3OH/10 mmol/L imidazole-HNO3 buffer (pH 7.0) (= 45:5:50, v/v/v %). The DBD derivatives were monitored at 565 nm with an excitation at 470 nm. The calibration curves showed good linearity (r = 0.997) with 0.5-15 ng/mL detection limits at a S/N ratio of 3. MDMA and MDA in rat urine could be monitored for 15 h after a single administration of MDMA to rat (2.0 mg/kg, i.p.). The concentrations for MDMA and MDA (n = 3) were 0.13-160.1 and 0.17-10.9 microg/mL, respectively. 相似文献
993.
Sexual differences in the crown units of mandibular molars were investigated in Australian Aborigines. The first and second deciduous molars (dm1 and dm2), and first to third permanent molars (M1, M2 and M3) were measured on dental casts using a sliding caliper. Measurements of tooth crowns included overall mesiodistal and buccolingual diameters, as well as the mesiodistal and buccolingual diameters of the trigonid and talonid. Percentage dimorphism values were greater in the talonid dimensions than the trigonid, indicating that sex differences tend to be larger in the later-developing crown units. Sex differences in mesiodistal diameters increased from dm1 to M2 but decreased for M3, the tooth that showed the least dimorphism of all the molars. This result seems to be due to the marked variability in size of the M3 between individuals. 相似文献
994.
Miyuki Matsuda Masaaki Kondo Shin-Ichi Kashiwabara Mitsuyo Yoshihara Shizuyo Sutou Shoichi Matsukuma 《The journal of histochemistry and cytochemistry》2004,52(9):1245-1248
A golgin family protein, Mea2, is expressed at enhanced level in pachytene spermatocytes and is indispensable for mouse spermatogenesis. Because Trax was shown to interact with Mea2 in yeast two-hybrid, we investigated the localization of Trax in pachytene spermatocytes with immunofluorescent staining. Trax was found to accumulate in the Golgi complex of mid-late pachytene spermatocytes and intermingled with granular Mea2 signal in the central region. In a subline of the Mea2 mutant mouse, a truncated form of Mea2 devoid of the N-terminal region, DeltaMea2, was expressed. It localized to the rim of Golgi complex and thus occupied a region separate from that of Trax. 相似文献
995.
Peng Li Qing-Li Zhao Paras Jawaid Mati Ur Rehman Hiroaki Sakurai Takashi Kondo 《Cell stress & chaperones》2016,21(5):873-881
KRAS mutant lung cancers have long been considered as untreatable with drugs. Transforming growth factor-β-activated kinase 1 (TAK1) appears to play an anti-apoptotic role in response to multiple stresses and has been reported to be a responsive kinase that regulates cell survival in KRAS-dependent cells. In this study, in order to find a useful approach to treat KRAS mutant lung cancer, we focused on the combined effects of 5Z-7-oxozeaenol, a TAK1 inhibitor, with hyperthermia (HT) in KRAS mutant lung cancer cell line A549. Annexin V-FITC/PI assay, cell cycle analysis, and colony formation assay revealed a significant enhancement in apoptosis induced by HT treatment, when the cells were pre-incubated with 5Z-7-oxozeaenol in a dose-dependent manner. The enhanced apoptosis by 5Z-7-oxozeaenol was accompanied by a significant increase in reactive oxygen species (ROS) generation and loss of mitochondrial membrane potential (MMP). In addition, western blot showed that 5Z-7-oxozeaenol enhanced HT-induced expressions of cleaved caspase-3, cleaved caspase-8, and HSP70 and decreased HT-induced expressions of Bcl-2, p-p38, p-JNK, and LC3. Moreover, 5Z-7-oxozeaenol pre-treatment resulted in a marked elevation of intracellular calcium level which might be associated with endoplasmic reticulum (ER) stress-related pathway. Taken together, our data provides further insights of the mechanism of action of 5Z-7-oxozeaenol and HT treatment, and their potential application as a novel approache to treat patients with KRAS mutant lung cancer. 相似文献
996.
Hattan Jun-ichiro Shindo Kazutoshi Ito Tomoko Shibuya Yurica Watanabe Arisa Tagaki Chie Ohno Fumina Sasaki Tetsuya Ishii Jun Kondo Akihiko Misawa Norihiko 《Planta》2016,243(4):959-972
Planta - A novel terpene synthase ( Tps ) gene isolated from Camellia brevistyla was identified as hedycaryol synthase, which was shown to be expressed specifically in flowers. Camellia plants are... 相似文献
997.
Hiromi?Ito Hiroyuki?Kaji Akira?Togayachi Parastoo?Azadi Mayumi?Ishihara Rudolf?Geyer Christina?Galuska Hildegard?Geyer Kazuaki?Kakehi Mitsuhiro?Kinoshita Niclas?G.?Karlsson Chunsheng?Jin Koichi?Kato Hirokazu?Yagi Sachiko?Kondo Nana?Kawasaki Noritaka?Hashii Daniel?Kolarich Kathrin?Stavenhagen Nicolle?H.?Packer Morten?Thaysen-Andersen Miyako?Nakano Naoyuki?Taniguchi Ayako?Kurimoto Yoshinao?Wada Michiko?Tajiri Pengyuan?Yang Weiqian?Cao Hong?Li Pauline?M.?RuddEmail author Hisashi?Narimatsu 《Glycoconjugate journal》2016,33(3):405-415
The Human Disease Glycomics/Proteome Initiative (HGPI) is an activity in the Human Proteome Organization (HUPO) supported by leading researchers from international institutes and aims at development of disease-related glycomics/glycoproteomics analysis techniques. Since 2004, the initiative has conducted three pilot studies. The first two were N- and O-glycan analyses of purified transferrin and immunoglobulin-G and assessed the most appropriate analytical approach employed at the time. This paper describes the third study, which was conducted to compare different approaches for quantitation of N- and O-linked glycans attached to proteins in crude biological samples. The preliminary analysis on cell pellets resulted in wildly varied glycan profiles, which was probably the consequence of variations in the pre-processing sample preparation methodologies. However, the reproducibility of the data was not improved dramatically in the subsequent analysis on cell lysate fractions prepared in a specified method by one lab. The study demonstrated the difficulty of carrying out a complete analysis of the glycome in crude samples by any single technology and the importance of rigorous optimization of the course of analysis from preprocessing to data interpretation. It suggests that another collaborative study employing the latest technologies in this rapidly evolving field will help to realize the requirements of carrying out the large-scale analysis of glycoproteins in complex cell samples. 相似文献
998.
999.
Yasuko Hirata Hilde Brems Mayu Suzuki Mitsuhiro Kanamori Masahiro Okada Rimpei Morita Isabel Llano-Rivas Toyoyuki Ose Ludwine Messiaen Eric Legius Akihiko Yoshimura 《The Journal of biological chemistry》2016,291(7):3124-3134
Constitutional heterozygous loss-of-function mutations in the SPRED1 gene cause a phenotype known as Legius syndrome, which consists of symptoms of multiple café-au-lait macules, axillary freckling, learning disabilities, and macrocephaly. Legius syndrome resembles a mild neurofibromatosis type 1 (NF1) phenotype. It has been demonstrated that SPRED1 functions as a negative regulator of the Ras-ERK pathway and interacts with neurofibromin, the NF1 gene product. However, the molecular details of this interaction and the effects of the mutations identified in Legius syndrome and NF1 on this interaction have not yet been investigated. In this study, using a yeast two-hybrid system and an immunoprecipitation assay in HEK293 cells, we found that the SPRED1 EVH1 domain interacts with the N-terminal 16 amino acids and the C-terminal 20 amino acids of the GTPase-activating protein (GAP)-related domain (GRD) of neurofibromin, which form two crossing α-helix coils outside the GAP domain. These regions have been shown to be dispensable for GAP activity and are not present in p120GAP. Several mutations in these N- and C-terminal regions of the GRD in NF1 patients and pathogenic missense mutations in the EVH1 domain of SPRED1 in Legius syndrome reduced the binding affinity between the EVH1 domain and the GRD. EVH1 domain mutations with reduced binding to the GRD also disrupted the ERK suppression activity of SPRED1. These data clearly demonstrate that SPRED1 inhibits the Ras-ERK pathway by recruiting neurofibromin to Ras through the EVH1-GRD interaction, and this study also provides molecular basis for the pathogenic mutations of NF1 and Legius syndrome. 相似文献
1000.
Katsuki Hirabayashi Nobuhiro Kondo Sachio Hayashi 《World journal of microbiology & biotechnology》2016,32(12):206
The chemical structure of hydrothermally treated β-1,3–1,6-glucan from Aureobasidium pullulans was characterized using techniques such as gas chromatography/mass spectrometry (GC/MS) and nuclear magnetic resonance (NMR). The chemical shifts of anomeric carbons observed in the 13C-NMR spectra suggested the presence of single flexible chains of polysaccharide in the sample. β-1,3–1,6-Glucan from A. pullulans became water-soluble, with an average molecular weight of 128,000 Da after hydrothermal treatment, and the solubility in water was approximately 10% (w/w). Sample (3% w/v) was completely hydrolyzed to glucose by enzymatic reaction with Lysing enzymes from Trichoderma harzianum. Gentiobiose (Glcβ1 → 6Glc) and glucose were released as products during the reaction, and the maximum yield of gentiobiose was approximately 70% (w/w). The molar ratio of gentiobiose to glucose after 1 h reaction suggested that the sample is likely highly branched. Sample (3% w/v) was also hydrolyzed to glucose by Uskizyme from Trichoderma sp., indicating that it is very sensitive to enzymatic hydrolysis. 相似文献