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11.
Polyclonal immunoglobulin (Ig) G autoantibodies against insulin have been identified in sera of healthy cats. We purified and fractionated insulin-binding IgGs from cat sera by affinity chromatography and analyzed affinity of insulin-binding IgGs for insulin and their epitopes. Following the passing of fraction A, which did not bind to insulin, insulin-binding IgGs were eluted into two fractions, B and C, by affinity chromatography using a column fixed with bovine insulin. Dissociation constant (KD) values between insulin-binding IgGs and insulin, determined by surface plasmon resonance analysis (Biacore™system), were 1.64e−4 M for fraction B (low affinity IgGs) and 2e−5 M for fraction C (high affinity IgGs). Epitope analysis was conducted using 16 peptide fragments synthesized in concord with the amino acid sequence of feline insulin by an enzyme-linked immunosorbent assay. Fractions B and C showed higher absorbance (affinity) of the peptide fragment of 10 amino acid residues at the carboxyl-terminal of the B chain (peptide No. 19), followed by peptide fragments of 6 to 15 amino acid residues of the B chain (peptide No. 8). Fraction C showed a higher absorbance to 7 to 16 amino acid residues of the B chain (peptide No. 5) compared with the absorbance of fraction B. Polyclonal insulin-binding IgGs may form a macromolecule complex with insulin through the multiple affinity sites of IgG molecules. Feline insulin-binding IgGs are multifocal and may be composed of multiple IgG components and insulin.  相似文献   
12.
A critical function of tumor suppressor p53 is the induction of apoptosis in cells exposed to noxious stresses. We report a previously unidentified pro-apoptotic gene, Noxa. Expression of Noxa induction in primary mouse cells exposed to x-ray irradiation was dependent on p53. Noxa encodes a Bcl-2 homology 3 (BH3)-only member of the Bcl-2 family of proteins; this member contains the BH3 region but not other BH domains. When ectopically expressed, Noxa underwent BH3 motif-dependent localization to mitochondria and interacted with anti-apoptotic Bcl-2 family members, resulting in the activation of caspase-9. We also demonstrate that blocking the endogenous Noxa induction results in the suppression of apoptosis. Noxa may thus represent a mediator of p53-dependent apoptosis.  相似文献   
13.
The aims of the present study were to determine whether salsolinol (SAL), a dopamine-related compound, is present in the bovine posterior pituitary (PP) gland, and to clarify the effect of SAL on the secretion of prolactin (PRL) in ruminants. SAL was detected in extract of bovine PP gland using high-pressure liquid chromatography with electrochemical detection (HPLC-EC). A single intravenous (i.v.) injection of SAL (5 and 10mg/kg body weight) significantly and dose-dependently stimulated the release of PRL in goats (P<0.05). Plasma PRL levels reached a peak 10min after the injection, then gradually returned to basal values in 60-80min. The PRL-releasing pattern was similar to that in response to sulpiride (a dopamine receptor antagonist). The intracerebroventricular (i.c.v.) injection of 1mg of SAL had no significant effect on the release of PRL in calves, however, 5mg significantly stimulated the release (P<0.05) with peak values reached 30-40min after the injection. Moreover, SAL significantly stimulated the release of PRL from cultured bovine anterior pituitary cells at doses of 10(-6) and 10(-5)M, compared to control cells (P<0.05). Taken together, our data clearly show that SAL is present in extract of the PP gland of ruminants, and has PRL-releasing activity both in vivo and in vitro. Therefore, this endogenous compound is a strong candidate for the factor having PRL-releasing activity that has been previously detected in extract of the bovine PP gland.  相似文献   
14.
In Sendai Bay, stone flounder larvae settle and spend their juvenile period in either shallow exposed inshore nursery grounds or estuarine nursery grounds. The purpose of this study is to examine the relative contributions of these two kinds of nursery grounds to the flounder population using otolith strontium:calcium ratios. Stone flounder juveniles were collected from both nursery grounds, and one- and two-year-old flounder were caught deeper in Sendai Bay. Sr and Ca content in the otoliths were measured by electron probe micro analysis. The Sr:Ca ratios in the otolith section corresponding to the early postsettlement period ranged from 3.06 to 3.85 for the exposed inshore areas with stable low temperature and high salinity conditions, and from 3.81 to 5.32 in brackish estuaries with high temperature and low salinity conditions but with large diel and tidal cyclical fluctuations. Values from an estuarine site with stable salinity ranged from 3.58 to 4.15 overlapping with both the above ranges. Rearing experiments supported our inference that the high otolith Sr:Ca ratios of juveniles inhabiting estuarine nursery grounds are attributable to higher temperature and physiological stress caused by the large diel temperature and salinity fluctuations within the estuaries. Estimation of the Sr:Ca ratio of recruited fish using the otolith section formed while in the nursery area showed that at least 20 out of 42 individuals examined originated from estuarine nursery grounds. The present study indicates that estuaries play an important role as nursery grounds for stone flounder, producing about half of the stock in spite of the small and restricted area compared with the wide expanse of the exposed inshore area.  相似文献   
15.
The transverse shrinkage variation within trees was examined for five sugi cultivars. The within-tree trends of tangential shrinkage (α T) were different by cultivar, whereas radial shrinkage (α R) increased from pith to bark in most cultivars. The tangential/radial shrinkage ratio (α T/α R) decreased from pith to bark in most cultivars, because the radial variation of α R was larger than that of α T. The cultivars showed significant differences among cultivars in α T, α R, and α T/α R, but the difference among cultivars for α T/α R was smaller. The relationships between transverse shrinkage and microfi bril angle (MFA), basic density (BD), tree ring parameters, and modulus of elasticity were examined. The α T and α R showed positive relationships with BD, latewood percentage, latewood density, and modulus of elasticity, and negative relationships with MFA and ring width. The relationships with earlywood density were weak. Sugi exhibited variation in transverse shrinkage within stem and among cultivars, with the variation affected by MFA, density, and tree ring parameters. Part of this article was presented at the 56th Annual Meeting of the Japan Wood Research Society, Akita, Japan, August 2006, and the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, Japan, August 2007  相似文献   
16.
ABSTRACT:   Color vision, spectral sensitivity, accommodation, and visual acuity were examined in juvenile masu salmon Oncorhynchus masou masou to obtain fundamental information about the visual system. Two types of S-potentials were recorded from 415 horizontal cells in isolated retinas from 34 cultured freshwater masu salmon (114–219 mm standard length, SL). Although horizontal cells recording S-potentials were not identified, the horizontal cells were confirmed because their responses were maintained while the stimulus remained. The variety of chromaticity (C)-type S-potentials indicated well-developed color vision. The analysis of the luminosity (L)-type S-potentials indicated that the peak spectral sensitivity was at 522 nm. S-potentials were also recorded in response to ultraviolet light. The direction and extent of lens movement induced by electrical stimulation was measured in 12 cultured masu salmon (99.0–142.5 mm SL). The results indicated that the visual axis was upward and forward, and that the range of accommodation was from 0.79 × SL in front of the eye to infinity. In histological analysis of the retinas of five wild smolts (100–118 mm SL), the maximum cone densities (276–345 cones/0.01 mm2) were detected in the ventral to temporal regions. The visual acuities assessed by histological methods were 0.069–0.075.  相似文献   
17.
Nucleotide sequences in internal transcribed spacer (ITS)-1 region derived from dried nori products produced in Japan, China, and the Republic of Korea were compared. Thalli contained in the Japanese products were genetically homogenous, and their nucleotide sequences in ITS-1 were identical to those of the reference strains of Pyropia yezoensis f. narawaensis. In Chinese products, the thalli were related to P. yezoensis strain Minomiasakusa. In contrast, the thalli in the Korean products were genetically heterogeneous, and several different P. yezoensis strains and other Pyropia spp. were used for dried nori products. In some thalli produced in both China and Korea, the DNA sequences of the ITS-1 region were identical with that of Japan, suggesting that the cultivar strains might have been transplanted from Japan to China in recent years. The 432-bp-long nucleotide sequences in the ITS-1 region of thalli derived from Japanese origin were cleaved to two restriction fragments at 154 and 278 bp by cleavage of PCR-amplified products using MspI. Conversely, almost all of the corresponding sequences derived from China and Korea were lacking MspI or other restriction patterns, except for nori products from some areas that cultivate a closely related strain to the Japanese cultivar.  相似文献   
18.
We examined differences in otolith oxygen (δ18Ootolith) and carbon (δ13Cotolith) stable isotope ratios between hatchery and wild pink salmon fry. The δ18Ootolith values of hatchery and wild fry were ?7.7 ± 0.2 ‰ and ?8.3 ± 0.3 ‰ (1σ), respectively. This difference reflected differences in temperature conditions experienced by each fry. The δ13Cotolith values of hatchery and wild fry were ?19.2 ± 0.3 ‰ and ?11.1 ± 1.8 ‰ (1σ), respectively. The lower δ13Cotolith values of hatchery fry were probably related to their intake of artificial diets. Discriminant analysis of δ18Ootolith and δ13Cotolith values demonstrated a highly significant difference between hatchery and wild fry with 95.8 % classification accuracy. Therefore, analysis of δ18Ootolith and δ13Cotolith precipitated in the fry stage may be useful for discriminating the origin of returning adult pink salmon. The discrimination method for returning adult fish would provide important information for evaluating the effect of hatchery release and their impact on the wild population.  相似文献   
19.
Tests of compression perpendicular to the grain were carried out on laminated veneer lumber (LVL) and timber. The species tested were sugi, radiata pine, karamatsu, akamatsu, and dahurian larch; two sets of sugi specimens were tested, with the sugi LVL products being manufactured in different plants. The strength properties of the materials for different loading directions were compared for LVL and timber. At 5% compressive strain in the same materials, the average stress in the tangential direction of timber was larger than that in the radial direction for all species except for radiata pine, and the average stress in the edge-wise direction of LVL was larger than that in the flat-wise direction for all species except for radiata pine. When the stress at 5% strain was compared in the same direction, the average stress of LVL in the edge-wise direction was larger than that in timber in the tangential direction for all species, but there were no great differences between the average stress of LVL in the fl at-wise direction and that of timber in the radial direction for all species except for radiation pine. There was a close relationship between density and stress at 5% strain in LVL, especially in the edge-wise direction. For all results, radiata pine did not follow the trend of the other species; The large annual ring width of radiata pine was considered to have affected the results.  相似文献   
20.
The serum concentration of C-reactive protein (CRP) in horses was measured by single radial immunodiffusion (SRID) using rabbit anti-equine CRP serum to evaluate the significance of CRP as an acute-phase reactive protein. In serum samples of clinically normal newborn thoroughbred foals before being given colostrum, serum CRP was not detectable (less than or equal to 1 microgram/ml). The serum CRP concentration was found to increase quickly and reach a peak level of approximately 14.1 micrograms/ml in 12-month-old horses. Then, it decreased gradually to reach a low value of 5.4 micrograms/ml in the 4-year-old. In horses over 5-year-old, serum CRP concentration was stable at values of 7 to 8 micrograms/ml. In mares during the peri-natal period, serum CRP concentration decreased at 2 months before delivery, showed moderate changes just before and after delivery, and then increased to relatively high level by 2 months after delivery. The concentration of serum CRP was found to be increased at 24 hours after experimentally inflammatory stimuli in adult horses, and reached peak values of 3 to 6 times as high as the base line values at 3 to 5 days. Serum CRP concentration returned to base line values by 2 to 3 weeks after treatments. It is clear from these data that CRP is one of the acute-phase reactive proteins in horses.  相似文献   
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