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61.
62.
Ikawa-Yoshida A Yoshii K Kuwahara K Obara M Kariwa H Takashima I 《Microbiology and immunology》2011,55(2):100-107
Tick-borne encephalitis (TBE) virus causes severe encephalitis with serious sequelae in humans. An epizootiological survey of wild rodents is effective to detect TBE virus-endemic areas; however, limited serological diagnostic methods are available to detect anti-TBE virus antibodies in wild rodents. In this study, ELISAs for the detection of rodent antibodies against the TBE virus were developed using two recombinant proteins, domain III of the E protein (EdIII) and subviral particles (SPs), as the antigens. As compared with the neutralization test, the ELISA using EdIII had 77.1% sensitivity and 80.0% specificity, and the ELISA using SPs had 91.4% sensitivity and 100% specificity. Furthermore, when the ELISAs were applied to the epizootiological survey in the TBE virus-endemic area, both of the ELISAs was able to detect wild rodents with TBE virus-specific antibodies. This is the first study to show that ELISAs using recombinant antigens can be safe and useful in the detection of TBE virus-infected wild rodents in epizootiological research. 相似文献
63.
We report the conformational analysis by 1H‐nmr and computer simulations of five potent sweet molecules, N‐(3,3‐dimethylbutyl)‐L ‐aspartyl‐S‐(α‐methyl)phenylalanine methylester (1; 5000 times more potent than sucrose), L ‐aspartyl‐D ‐valine (S)‐α‐methoxycarbonylmethylbenzylamide (2; 1400 times more potent than sucrose), L ‐aspartyl‐D ‐valine α‐phenylcyclopentylamide (3; 1200 times more potent than sucrose), L ‐aspartyl‐D ‐α‐aminobutyric acid (S)‐α‐cyclohexylpropylamide (4; 2300 times more potent than sucrose), and L ‐aspartyl‐D ‐valine (R)‐α‐methylthiomethylbenzylamide (5; 3000 times more potent than sucrose). The “L‐shaped” structure, which we believe to be responsible for sweet taste, is accessible to all five sweet compounds in solution. This structure is characterized by a zwitterionic ring formed by the A‐H and B containing moieties located in the +y axis and by the hydrophobic group X pointing into the +x axis. Other accessible conformations of these flexible molecules are extended conformations with the A‐H and B containing moieties in the +y axis and the hydrophobic group X pointing in the −y axis and reversed L‐shaped structures with the hydrophobic group X projecting along the −x axis. The remarkable potency of the N‐alkylated compound 1 supports our recent hypothesis that a second hydrophobic binding domain in addition to interactions arising from the L‐shaped structure leads to an enhancement of sweetness potency. © 1999 John Wiley & Sons, Inc. Biopoly 49: 525–539, 1999 相似文献
64.
Yusuke Kuriki Younan Liu Dengsheng Xia Eva M. Gjerde Saeed Khalili Brennan Mui Changyu Zheng Simon D. Tran 《Journal of visualized experiments : JoVE》2011,(51)
Severe salivary gland hypofunction is frequently found in patients with Sjögren''s syndrome and those who receiving therapeutic
irradiation in their head and neck regions for cancer treatment. Both groups of patients experience symptoms such as xerostomia (dry mouth), dysphagia
(impaired chewing and swallowing), severe dental caries, altered taste, oro-pharyngeal infections (candidiasis), mucositis, pain and discomfort.One innovative approach of regenerative medicine for the treatment of salivary gland hypo-function is speculated in RS Redman, E Mezey
et al. 2009: stem cells can be directly deposited by cannulation into the gland as a potent method in reviving the functions of the impaired organ. Presumably,
the migrated foreign stem cells will differentiate into glandular cells to function as part of the host salivary gland. Also, this cannulation technique is an
expedient and effective delivery method for clinical gene transfer application.Here we illustrate the steps involved in performing the cannulation procedure on the mouse submandibular salivary gland via the Wharton''s duct
(Fig 1). C3H mice (Charles River, Montreal, QC, Canada) are used for this experiment, which have been kept under clean conventional conditions at
the McGill University animal resource center. All experiments have been approved by the University Animal Care Committee and were in accordance with the
guidelines of the Canadian Council on Animal Care.For this experiment, a trypan blue solution is infused into the gland through the opening of the Wharton''s duct using a
insulin syringe with a 29-gauge needle encased inside a polyethylene tube. Subsequently, the mouse is dissected to show that the infusions migrated
into the gland successfully. Download video file.(31M, mov) 相似文献
65.
Satoshi Ueno Masaomi Minaba Yuji Nishiuchi Misako Taichi Yasushi Tamada Toshimasa Yamazaki Yusuke Kato 《Annals of clinical microbiology and antimicrobials》2011,10(1):1-7
Background
The accessory gene regulator (agr) is a quorum sensing cluster of genes which control colonization and virulence in Staphylococcus aureus. We evaluated agr function in community- (CA) and healthcare-associated (HA) MRSA, to compare the pharmacodynamics and bactericidal activity of vancomycin against agr functional and dysfunctional HA-MRSA and CA-MRSA.Methods
40 clinical isolates of MRSA from the Canadian Nosocomial Infection Surveillance Program were evaluated for delta-haemolysin production, as a surrogate marker of agr function. Time kill experiments were performed for vancomycin at 0 to 64 times the MIC against an initial inoculum of 106 and 108 cfu/ml of agr functional and dysfunctional CA-MRSA and HA-MRSA and these data were fit to a hill-type pharmacodynamic model.Results
15% isolates were agr dysfunctional, which was higher among HA-MRSA (26.3%) versus CA-MRSA (4.76%). Against a low initial inoculum of 106 cfu/ml of CA-MRSA, vancomycin pharmacodynamics were similar among agr functional and dysfunctional strains. However, against a high initial inoculum of 108 cfu/ml, killing activity was notably attenuated against agr dysfunctional CA-MRSA (USA400) and HA-MRSA (USA100). CA-MRSA displayed a 20.0 fold decrease in the maximal reduction in bacterial counts (Emax) which was 3.71 log10 CFU/ml for agr functional vs. 2.41 log10 CFU/ml for agr dysfunctional MRSA (p = 0.0007).Conclusions
Dysfunction in agr was less common among CA-MRSA vs. HA-MRSA. agr dysfunction demonstrated an impact on vancomycin bactericidal activity and pharmacodynamics against a high initial inoculum of CA-MRSA and HA-MRSA, which may have implications for optimal antimicrobial therapy against persistent, difficult to treat MRSA infections. 相似文献66.
Kanji Ishizaki Asao Noda Mituo Ikenaga Kenji Ida Keiichi Omoto Yusuke Nakamura Ken-ichi Matsubara 《Human genetics》1985,71(3):261-262
Summary The plasmid clone which contains human salivary amylase cDNA was used to detect restriction fragment length polymorphisms
(RFLPs). After double digestion with Pst 1 and Bam H1, a polymorphism with two alleles was observed. In Japanese, frequencies of these alleles, tentatively called 5.7kb and 6.5kb
fragment alleles, are 0.55 and 0.45, respectively. 相似文献
67.
Yamamori T Yasui H Yamazumi M Wada Y Nakamura Y Nakamura H Inanami O 《Free radical biology & medicine》2012,53(2):260-270
Whereas ionizing radiation (Ir) instantaneously causes the formation of water radiolysis products that contain some reactive oxygen species (ROS), ROS are also suggested to be released from biological sources in irradiated cells. It is now becoming clear that these ROS generated secondarily after Ir have a variety of biological roles. Although mitochondria are assumed to be responsible for this Ir-induced ROS production, it remains to be elucidated how Ir triggers it. Therefore, we conducted this study to decipher the mechanism of Ir-induced mitochondrial ROS production. In human lung carcinoma A549 cells, Ir (10 Gy of X-rays) induced a time-dependent increase in the mitochondrial ROS level. Ir also increased mitochondrial membrane potential, mitochondrial respiration, and mitochondrial ATP production, suggesting upregulation of the mitochondrial electron transport chain (ETC) function after Ir. Although we found that Ir slightly enhanced mitochondrial ETC complex II activity, the complex II inhibitor 3-nitropropionic acid failed to reduce Ir-induced mitochondrial ROS production. Meanwhile, we observed that the mitochondrial mass and mitochondrial DNA level were upregulated after Ir, indicating that Ir increased the mitochondrial content of the cell. Because irradiated cells are known to undergo cell cycle arrest under control of the checkpoint mechanisms, we examined the relationships between cell cycle and mitochondrial content and cellular oxidative stress level. We found that the cells in the G2/M phase had a higher mitochondrial content and cellular oxidative stress level than cells in the G1 or S phase, regardless of whether the cells were irradiated. We also found that Ir-induced accumulation of the cells in the G2/M phase led to an increase in cells with a high mitochondrial content and cellular oxidative stress level. This suggested that Ir upregulated mitochondrial ETC function and mitochondrial content, resulting in mitochondrial ROS production, and that Ir-induced G2/M arrest contributed to the increase in the mitochondrial ROS level by accumulating cells in the G2/M phase. 相似文献
68.
69.
Yusuke Morita Naomichi Ogihara Takashi Kanai Hiromasa Suzuki 《American journal of physical anthropology》2013,151(4):658-666
Three‐dimensional geometric morphometric techniques have been widely used in quantitative comparisons of craniofacial morphology in humans and nonhuman primates. However, few anatomical landmarks can actually be defined on the neurocranium. In this study, an alternative method is proposed for defining semi‐landmarks on neurocranial surfaces for use in detailed analysis of cranial shape. Specifically, midsagittal, nuchal, and temporal lines were approximated using Bezier curves and equally spaced points along each of the curves were defined as semi‐landmarks. The shortest paths connecting pairs of anatomical landmarks as well as semi‐landmarks were then calculated in order to represent the surface morphology between landmarks using equally spaced points along the paths. To evaluate the efficacy of this method, the previously outlined technique was used in morphological analysis of sexual dimorphism in modern Japanese crania. The study sample comprised 22 specimens that were used to generate 110 anatomical semi‐landmarks, which were used in geometric morphometric analysis. Although variations due to sexual dimorphism in human crania are very small, differences could be identified using the proposed landmark placement, which demonstrated the efficacy of the proposed method. Am J Phys Anthropol 151:658–666, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
70.
Food habits of fishes in the surf zone of a sandy beach at Sanrimatsubara, Fukuoka Prefecture, Japan 总被引:1,自引:1,他引:1
To clarify the feeding habits of fishes in surf zones, the gut contents of 19 fish species collected in the surf zone of a sandy beach at Sanrimatsubara, western Japan, were examined. Ontogenetic changes in food preference were recognized in seven species (Mugil cephalus cephalus, Lateolabrax latus, Sillago japonica, Paralichthys olivaceus, Paraplagusia japonica, Takifugu poecilonotus, and Takifugu niphobles). A cluster analysis based on dietary overlaps showed that the surf zone fish assemblage comprised six trophic groups (zooplankton, benthic and epiphytic crustacean, detritus, polychaete, fish, and insect feeders). Of these, the most abundant trophic group was zooplankton feeders, along with benthic and epiphytic crustacean feeders. 相似文献