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991.
992.
Kido S Hasebe N Ishii Y Kikuchi K 《American journal of physiology. Heart and circulatory physiology》2006,290(3):H1064-H1070
The aim of this study was to investigate what factor determines tachycardia-induced secretion of atrial and brain natriuretic peptides (ANP and BNP, respectively) in patients with hypertrophic cardiomyopathy (HCM). HCM patients with normal left ventricular (LV) systolic function and intact coronary artery (n = 22) underwent rapid atrial pacing test. The cardiac secretion of ANP and BNP and the lactate extraction ratio (LER) were evaluated by using blood samples from the coronary sinus and aorta. LV end-diastolic pressure (LVEDP) and the time constant of LV relaxation of tau were measured by a catheter-tip transducer. These parameters were compared with normal controls (n = 8). HCM patients were divided into obstructive (HOCM) and nonobstructive (HNCM) groups. The cardiac secretion of ANP was significantly increased by rapid pacing in HOCM from 384 +/- 101 to 1,268 +/- 334 pg/ml (P < 0.05); however, it was not significant in control and HNCM groups. In contrast, the cardiac secretion of BNP was fairly constant and rather significantly decreased in HCM (P < 0.01). The cardiac ANP secretion was significantly correlated with changes in LER (r = -0.57, P < 0.01) and tau (r = 0.73, P < 0.001) in HCM patients. Tachycardia potentiates the cardiac secretion of ANP, not BNP, in patients with HCM, particularly when it induces myocardial ischemia and LV diastolic dysfunction. 相似文献
993.
Shinsuke Nakai 《Human ecology: an interdisciplinary journal》2009,37(4):501-511
Previous studies on the hillside farmers of northern Thailand often focused on their swidden (slash-and-burn) agriculture
of upland rice and cash crop cultivation and paid little attention to livestock production and consumption, including that
of pigs. I describe the household-level pig production and consumption in terms of the number of pigs slaughtered and the
number of pigs supplied to others, or acquired from others, in a Hmong village of smallholders in northern Thailand. Study
results are based on pig consumption in 17 selected households over two years (January 2005 to December 2006). The number
of pigs slaughtered in each household ranged from zero to ten, with an average of 2.4 pigs per household per year. Pigs were
slaughtered mainly for ritual events, particularly for annual ancestor worship and New Year ceremonies. A total of 80 pigs
were slaughtered, with 78% being killed during ritual events including Christmas and 22% for non-ritual events including children
moving up a grade in school. Most Christian households stopped slaughtering of pigs in ancestor worship conducted by a shaman,
but continued to do so in Christmas and New Year rituals. A total of 23 pigs were supplied to others, of which two were given
to people outside the village, while of a total of 37 pigs acquired, 17 were obtained from outside the village. A total of
80 pigs were slaughtered, including one improved-breed pig that was killed during a marriage ceremony soon after it was acquired
from the city. The following changes in pig consumption are inferred to have taken place due to recent socioeconomic changes:
(1) diversification of the type of events in which pigs are slaughtered as a result of the introduction of Christianity and
the national educational system; (2) active pig acquisition from outside the village as a result of the use of motor vehicles;
and (3) the acquisition and slaughtering for events of improved-breeds of pigs which are not kept and used for breeding. 相似文献
994.
Asahi Ito Takashi Ishida Hiroki Yano Atsushi Inagaki Susumu Suzuki Fumihiko Sato Hisashi Takino Fumiko Mori Masaki Ri Shigeru Kusumoto Hirokazu Komatsu Shinsuke Iida Hiroshi Inagaki Ryuzo Ueda 《Cancer immunology, immunotherapy : CII》2009,58(8):1195-1206
Purpose There are no suitable small animal models to evaluate human antibody-dependent cellular cytotoxicity (ADCC) in vivo, due to
species incompatibilities. Thus, the first aim of this study was to establish a human tumor-bearing mouse model in which human
immune cells can engraft and mediate ADCC, but where the endogenous mouse immune cells cannot mediate ADCC. The second aim
was to evaluate ADCC mediated in these humanized mice by the defucosylated anti-CC chemokine receptor 4 (CCR4) monoclonal
antibody (mAb) which we have developed and which is now in phase I clinical trials.
Experimental design NOD/Shi-scid, IL-2Rγnull (NOG) mice were the recipients of human immune cells, and CCR4-expressing Hodgkin lymphoma (HL) and cutaneous T-cell lymphoma
(CTCL) cell lines were used as target tumors.
Results Humanized mice have been established using NOG mice. The chimeric defucosylated anti-CCR4 mAb KM2760 showed potent antitumor
activity mediated by robust ADCC in these humanized mice bearing the HL or CTCL cell lines. KM2760 significantly increased
the number of tumor-infiltrating CD56-positive NK cells which mediate ADCC, and reduced the number of tumor-infiltrating FOXP3-positive
regulatory T (Treg) cells in HL-bearing humanized mice.
Conclusions Anti-CCR4 mAb could be an ideal treatment modality for many different cancers, not only to directly kill CCR4-expressing tumor
cells, but also to overcome the suppressive effect of Treg cells on the host immune response to tumor cells. In addition,
using our humanized mice, we can perform the appropriate preclinical evaluation of many types of antibody based immunotherapy. 相似文献
995.
Narihito Nagoshi Shinsuke Shibata Masaya Nakamura Yumi Matsuzaki Yoshiaki Toyama Hideyuki Okano 《Journal of cellular biochemistry》2009,107(6):1046-1052
A recent burst of findings has shown that neural crest‐derived stem cells (NCSCs) can be found in diverse mammalian tissues. In addition to their identification in tissues that are known to be derived from the neural crest, recent studies have revealed NCSCs in tissues that are not specifically derived from the neural crest, such as bone marrow. NCSCs can express a wide range of characteristics, and which properties are expressed mainly depends on their tissue sources and the ontogenic stage of the animal. The identification of NCSCs in various tissues opens an entirely new avenue of approach to developing autologous cell replacement therapies for use in regenerative medicine. In this review, we discuss the origin, migration, and lineage potential of NCSCs from various mammalian tissue sources. J. Cell. Biochem. 107: 1046–1052, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
996.
Seiichi Katayama Nanami Nozu Masaya Okuda Shinsuke Hirota Tsutomu Yamasaki Yasuo Hitsumoto 《Anaerobe》2009,15(4):155-159
Clostridium perfringens is a Gram-positive anaerobic pathogen that causes gas gangrene and food poisoning in humans and animals. Genomic analysis of C. perfringens strain 13 revealed that this bacterium contains two genes (CPE0737 and CPE1847) that encode putative fibronectin (Fn)-binding proteins (Fbps). These genes, named fbpA and fbpB, were found to be constitutively expressed in all three strains (13, NCTC8237, CPN50) of C. perfringens, isolated from gas gangrene of human, that were tested. Both fbpA and fbpB were cloned and His-tagged, recombinant FbpA (rFbpA) and recombinant FbpB (rFbpB) were purified by Ni2+-Sepharose column chromatography from transformed Escherichia coli. These recombinant Fbps were shown to bind to Fn, purified from human serum, in a ligand blotting assay. Additionally, Fn bound to these rFbps in a dose-dependent manner in an enzyme-linked immunosorbent assay. Furthermore, it was found that pre-incubation of Fn with either rFbpA or rFbpB inhibited the binding of Fn to C. perfringens cells. 相似文献
997.
998.
Chiaki Inaba Shinsuke Higuchi Hironobu Morisaka Kouichi Kuroda Mitsuyoshi Ueda 《Applied microbiology and biotechnology》2010,86(6):1895-1902
Carnosine (β-alanyl-l-histidine) is one of the bioactive dipeptides and has antioxidant, antiglycation, and cytoplasmic buffering properties. In
this study, to synthesize carnosine from nonprotected amino acids as substrates, we cloned the carnosinase (CN1) gene and
constructed a whole-cell biocatalyst displaying CN1 on the yeast cell surface with α-agglutinin as the anchor protein. The
display of CN1 was confirmed by immunofluorescent labeling, and CN1-displaying yeast cells showed hydrolytic activity for
carnosine. When carnosine was synthesized by the reverse reaction of CN1, organic solvents were added to the reaction mixture
to reduce the water content. The CN1-displaying yeast cells were lyophilized and examined for organic solvent tolerance. Results
showed that the CN1-displaying yeast cells retained their original hydrolytic activity in hydrophobic organic solvents. In
the hydrophobic organic solvents and hydrophobic ionic liquids, the CN1-displaying yeast cells catalyzed carnosine synthesis,
and carnosine was synthesized from nonprotected amino acids in only one step. The results of this research suggest that the
whole-cell biocatalyst displaying CN1 on the yeast cell surface can be used to synthesize carnosine with ease and convenience. 相似文献
999.
The kinesin, dynein, and myosin superfamily molecular motors have fundamental roles in neuronal function, plasticity, morphogenesis, and survival by transporting cargos such as synaptic vesicle precursors, neurotransmitter and neurotrophic factor receptors, and mRNAs within axons, dendrites, and synapses. Recent studies have begun to clarify the mechanisms of cargo selection and directional transport in subcellular compartments. Furthermore, molecular genetics has revealed unexpected roles for molecular motors in brain wiring, neuronal survival, neuronal plasticity, higher brain function, and control of central nervous system and peripheral nervous system development. Finally, it is also evident that molecular motors are critically involved in neuronal disease pathogenesis. Thus, molecular motor research is becoming an exciting frontier of neuroscience. 相似文献
1000.
T Yasuda Z Mohri Y Murakami T Takagi Y Otsuki K Miyai O Tanizawa 《Endocrinologia japonica》1989,36(5):641-646
A competitive, double antibody enzyme immunoassay for oxytocin in a heterologous system was developed. Horseradish peroxidase was conjugated with oxytocin using N-succinimidyl 3-(2-pyridyldithio) propionate, and rabbit anti-oxytocin serum was produced by immunization of oxytocin-bovine serum albumin complex which was prepared by the carbodiimide method. The sensitivity of the assay was 4 microIU/tube, which corresponded to 10 microIU per ml using 400 microliters of the sample which was extracted from the same volume of plasma by means of SEP-PAK C18 cartridges. The coefficients of variation for different levels of oxytocin ranged from 6.8-15.9% and 8.5-16.7%, for intra- and inter-assay. Recovery of oxytocin added to plasma after extraction was 99-117%. No or little cross-reaction with arginine- and lysine-vasopressin was found. Plasma oxytocin concentrations determined by the proposed enzyme immunoassay were well correlated with those determined by radioimmunoassay (r = 0.90). 相似文献