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41.
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Y Chiba J L Dzierba A Morag P L Ogra 《Journal of immunology (Baltimore, Md. : 1950)》1976,116(1):12-15
The antibody and cell-mediated immune response to mumps virus infection was studied in groups of subjects after natrually acquired mumps virus infection, after parenteral immunization with live attenuated mumps vaccine, and in a population of mumps seronegative subjects. The technique of neutralization of tissue culture infectivity was utilized to study mumps specific antibody. The cell-mediated immunity (CMI) was detected by specific immune release (SIR) of radioactivity by purified lymphocytes after they were reacted with radioactive chromium (51Cr) labeled human conjunctival cell cultures chronically infected with mumps virus. No SIR activity was observed in lymphocytes obtained from cord blood and young individuals seronegative for antibody to mumps virus. Detectable SIR activity was observed in a few older seronegative subjects; however, immunization with mumps vaccine in such antibody negative subjects failed to result in the development of any antibody response in the serum. High SIR activity was observed in the lymphocytes of naturally infected and vaccinated subjects. Although all naturally infected or immunized subjects had varying levels of mumps specific antibody activity in the serum, no correlation existed between the levels of antibody and SIR activity. These observations suggest the development of mumps specific in vitro correlates of CMI after naturally acquired or vaccine-induced mumps virus infection. 相似文献
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Carbamoylcholine (carbachol) has been shown to inhibit somatostatin release from gastric D-cells. We observed that this dose-dependent inhibitory effect was accompanied by decreases in cellular cyclic adenosine 3':5'-monophosphate (cAMP) production and increases in parameters of membrane inositol phospholipid turnover. However, after pretreatment of D-cells with pertussis toxin (200 ng/ml), carbachol paradoxically stimulated basal somatostatin release and potentiated the secretagogue action of forskolin. Pertussis toxin pretreatment blocked the ability of carbachol to decrease cAMP production but changes in inositol phospholipid turnover were unaffected. Atropine reversed all of the observed changes induced by carbachol. These data suggest that muscarinic cholinergic receptors mediate both stimulatory and inhibitory regulation of D-cells. The inhibitory effect may involve pertussis toxin-sensitive inhibitory guanine nucleotide binding proteins while the stimulatory effect may result from the consequences of membrane phosphoinositide turnover. 相似文献
46.
The physicochemical properties and chemical constituents of the blue protein from rice bran were investigated. The blue protein was a copper-containing glycoprotein, the molecular weight of which was found to be 18,300 Daltons by the sedimentation equilibrium method assuming the partial specific volume 0.72 cm3 g?1. The hexose and pentose contents were 5.49 and 4.01 g per 100 g protein respectively. The copper content was 0.38% which corresponded to 1.09 atoms per one molecule of the protein. The electron spin resonance spectrum showed that the copper was in a cupric state. The standard oxidation-reduction potential of the copper was found to be +275 mV at 20°C and at pH 7.39. The visible and near infrared absorption maxima were found at 450, 600 and 890 mμ, and the 450 mμ band was optically active in the optical rotatory dispersion exhibiting a large Cotton effect. 相似文献
47.
Shoichi Fujita Issei Chiba Mayumi Ishizuka Hidenobu Hoshi Hisato Iwata Akihito Sakakibara 《Biomarkers》2013,18(1):19-25
The impact of environmental pollution on selected animals was tested by monitoring the hepatic content of cytochromes P450 and their enzyme activities or by calculating TEQ values from the concentration of pollutants in the body. Fish-eating Stellars Sea Eagles, Haliaeetus pelagicus, found dead in the northern part of Hokkaido island accumulated high levels of PCBs and DDT and metabolites. The TEQ values calculated from the PCB concentration in the eagles were high enough to cause a significant toxic effect in other birds living in the same environment. Some of these birds were also contaminated with high concentrations of lead. Spotted seals, Phoca largha, captured along the coast-line of Hokkaido accumulated PCBs in their fat at about 100 million times the concentrations in the surface sea water. The levels of expressions of hepatic microsomal CYP 1A1and related enzyme activities in these seals showed good correlation to the levels of PCBs accumulated in the fat. The fresh water crabs, Eriocheir japonicus, were captured from three different rivers with various degrees of pollution. The P450 content and the related enzyme activities showed good correlation to TEQ values obtained from the concentrations of PCBs and PCDDs in the crabs from the rivers. The wild rodents, Clethrionomys rufocanus, were captured from urban, agricultural, and forest areas in Hokkaido. Those from the forest area had the lowest CYP content and related enzyme activities, comparable to those in laboratory-raised animals. Those from the urban areas, presumably contaminated with PAHs from fuel combustion, showed increased CYP 1A1 content and related enzyme activities. Those from the agricultural areas showed increased levels of CYP 1A1, 2B, 2E1. Rats treated with some of the agrochemicals used in the area resulted in a similar pattern of induction. It is concluded that P450 can be a useful biomarker for assessing the environmental impact of chemical pollutants on wild animals. 相似文献
48.
Shuhei Chiba Yuta Amagai Yuta Homma Mitsunori Fukuda Kensaku Mizuno 《The EMBO journal》2013,32(6):874-885
Primary cilia are antenna‐like sensory organelles protruding from the plasma membrane. Defects in ciliogenesis cause diverse genetic disorders. NDR2 was identified as the causal gene for a canine ciliopathy, early retinal degeneration, but its role in ciliogenesis remains unknown. Ciliary membranes are generated by transport and fusion of Golgi‐derived vesicles to the pericentrosome, a process requiring Rab11‐mediated recruitment of Rabin8, a GDP–GTP exchange factor (GEF) for Rab8, and subsequent Rab8 activation and Rabin8 binding to Sec15, a component of the exocyst that mediates vesicle tethering. This study shows that NDR2 phosphorylates Rabin8 at Ser‐272 and defects in this phosphorylation impair preciliary membrane assembly and ciliogenesis, resulting in accumulation of Rabin8‐/Rab11‐containing vesicles at the pericentrosome. Rabin8 binds to and colocalizes with GTP‐bound Rab11 and phosphatidylserine (PS) on pericentrosomal vesicles. The phospho‐mimetic S272E mutation of Rabin8 decreases affinity for PS but increases affinity for Sec15. These results suggest that NDR2‐mediated Rabin8 phosphorylation is crucial for ciliogenesis by triggering the switch in binding specificity of Rabin8 from PS to Sec15, thereby promoting local activation of Rab8 and ciliary membrane formation. 相似文献
49.
Ryoko Okajima Satoshi Chiba 《Evolution; international journal of organic evolution》2013,67(2):429-437
The adaptations that occur for support and protection can be studied with regard to the optimal structure that balances these objectives with any imposed constraints. The shell inclination of terrestrial gastropods is an appropriate model to address this problem. In this study, we examined how gastropods improve shell angles to well‐balanced ones from geometrically constrained shapes. Our geometric analysis and physical analysis showed that constantly coiled shells are constrained from adopting a well‐balanced angle; the shell angle of such basic shells tends to increase as the spire index (shell height/width) increases, although the optimum angle for stability is 90° for flat shells and 0° for tall shells. Furthermore, we estimated the influences of the geometric rule and the functional demands on actual shells by measuring the shell angles of both resting and active snails. We found that terrestrial gastropods have shell angles that are suited for balance. The growth lines of the shells indicated that this adaptation depends on the deflection of the last whorl: the apertures of flat shells are deflected downward, whereas those of tall shells are deflected upward. Our observations of active snails demonstrated that the animals hold their shells at better balanced angles than inactive snails. 相似文献
50.
Yuusuke Tamura Kyouhei Hayashi Naoki Omori Yuji Nishiura Kana Watanabe Nobuyuki Tanaka Masahiko Fujioka Naoki Kouyama Akira Yukimasa Yukari Tanaka Takeshi Chiba Hideki Tanioka Hirohide Nambu Hideo Yukioka Hiroki Sato Takayuki Okuno 《Bioorganic & medicinal chemistry letters》2013,23(1):90-95
Optimization of HTS hit 1 for NPY Y5 receptor binding affinity, CYP450 inhibition, solubility and metabolic stability led to the identification of some orally available oxygen-linker derivatives for in vivo study. Among them, derivative 4i inhibited food intake induced by the NPY Y5 selective agonist, and chronic oral administration of 4i in DIO mice caused a dose-dependent reduction of body weight gain. 相似文献