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51.
Japanese pear (Pyrus pyrifolia) exhibits gametophytic self-incompatibility (GSI) controlled by a complex and multiallelic S locus. The pistil-part product of the S locus is the polymorphic ribonuclease, S-RNase. Information on S-genotypes is important for the production and breeding of Japanese pears. Molecular analyses of S-genotypes of Japanese pear have been conducted with the CAPS (cleaved amplified polymorphic sequence) system; PCR amplification of S-RNase fragments by a common primer pair followed by digestion with restriction enzymes each of which cleaves a specific S haplotype. Here, we show that the separation of S-RNase fragments by polyacrylamide gel electrophoresis (PAGE) distinguishes four out of nine S haplotypes of Japanese pear without restriction digestion. S3-, S5-, S6- and S8-RNases were identified as distinct bands by PAGE. S3- and S5-RNases were separated by PAGE despite their identical fragment sizes. Using this system, three Japanese pear lines with unknown S-genotypes were analyzed. The newly determined S-genotypes of the lines were confirmed by CAPS analysis.  相似文献   
52.
The expression of the major histocompatibility complex (MHC) classical class I genes is important for the adaptive immune response to target virus-infected cells and cancer cells. The up-regulation of the MHC is achieved by hormonal/cytokine signals including IFN-γ-inducible elements. The swine leukocyte antigen (SLA), the MHC class I region of pigs, consists of the duplicated classical class I genes, SLA-1, SLA-2 and SLA-3, but the molecular mechanisms involved in their up-regulation after T cell stimulation have not been fully elucidated. In order to better understand some of the putative regulatory mechanisms of SLA class I gene expression in activated T cells, we examined the coordinated expression of the SLA classical class I, IFN-γ and interferon regulatory factor-1 (IRF-1) genes in the peripheral blood mononuclear cells (PBMCs) of SLA homozygous Clawn miniature swine stimulated for 72h with either IFN-γ or an enterotoxin produced by Staphylococcus aureus. This enterotoxin, toxic shock syndrome-1 (TSST-1), is known to act as a superantigen (sAG) to activate the T cells in various vertebrate species. We showed by using mAbs and flow cytometry that the CD4(+)CD25(+) cell number of swine PBMCs was also increased by TSST-1 and to a lesser degree by IFN-γ. Time course analyses of the expression of the IFN-γ, IRF-1 and the three classical class I genes, SLA-1, SLA-2, and SLA-3, in PBMCs by quantitative real-time PCR revealed a transitory response to TSST-1 or IFN-γ stimulation. The IFN-γ mRNA levels in the PBMCs were continuously up-regulated over the first 48h by TSST-1 or IFN-γ. In contrast, SLA class I expression moderately increased at 24h and then decreased to a baseline level or less at 72h of IFN-γ or TSST-1 stimulation. The three classical SLA class I genes showed similar expression kinetics, although SLA-3 mRNA level was consistently lower than those of SLA-1 and -2. The expression of IRF-1, a modulator of SLA expression, showed similar kinetics to those of the three classical SLA class I genes. The expression profiles detected by flow cytometry of the SLA molecules on the cell surface of PBMCs were maintained at a consistently high level during cell stimulation with either TSST-1 or IFN-γ, which was distinct from the kinetics of mRNA expression. These results showed that miniature swine SLA class I mRNA expression was effectively and equally up-regulated among the three loci and coordinately with IRF-1 gene expression after stimulation of T cell activation by sAG or IFN-γ.  相似文献   
53.
A simple method of lymphography of the thoracic duct was investigated. Using three female beagles, contrast media were administered rectally, vaginally and into the perianal tissue. The administration sites were gently massaged, and imaging was carried out at constant intervals using computed tomography and radiograph. Moreover, Indian ink was administered into the rectum mucous membrane in dogs for proof of this method of lymphography, and the lymph drainage routes were observed. The investigation showed that clear computed tomography and radiographic contrast images of the thoracic duct were obtained by subcutaneous and submucosa injection of angiography contrast medium and 3D processing of these images revealed the three-dimensional positions and course of the thoracic duct and cisterna chyli.  相似文献   
54.
The effects of laser incising on the surface of heat-affected zones (HAZs) and liquid uptake of wood were examined. Deep pin holes were incised on the tangential section of the wood with a laser beam of 1 kW in power with varied pulse widths, and the HAZs of the holes were investigated using scanning electron microscopy. The length of liquid uptake passing through HAZs surfaces was then measured. It was observed that the HAZs were unable to maintain normal porous structure, and smooth surfaces such as that of wood charcoal were also not observed. This is because the composite of the middle lamella completely melted, which led to a decrease in the length of liquid uptake. In addition, the release of high gas-pressure and thermal energy during the laser-incising process did not damage the tylose and the aspirated pit in the longitudinal direction. Because of this, the liquid movement remained blocked. However, the incising holes provided additional liquid-intake points, resulting in greater intake capacity. Moreover, it was observed that improvement of liquid impregnation is related to hole diameter.  相似文献   
55.
To understand the viscoelasticity of wood three dimensionally, matched samples of Japanese cypress were loaded in uniaxial tensile creep in the longitudinal (L), radial (R), and tangential (T) directions at approximately 9.7 % equilibrium moisture content. Longitudinal and transverse strains were measured for the determination of viscoelastic Poisson’s ratios and three-dimensional viscoelastic compliance tensors concerning the normal strain. The changes in the transverse strains showed the same tendencies as those in the longitudinal strains, in all directions of loading. That is, during creep, the absolute value of transverse strain continued to increase with the gradual reduction in the increase rate; immediately after the removal of the load, it recovered rapidly, after which it continued to recover slowly. The transverse strain increased most easily in the T direction, followed by R and L, during creep. All the viscoelastic Poisson’s ratios and the absolute values of all elements of the viscoelastic compliance increased logarithmically with creep time. The three-dimensional viscoelastic compliance matrix for Japanese cypress is concluded to be asymmetric.  相似文献   
56.
Historical control data of tumor incidence were collected from the control groups (215 animals of each sex) in four recent carcinogenicity studies that were started between 2005 to 2009 (terminally sacrificed between 2007 and 2011) at BoZo Research Center Inc. (Gotemba, Shizuoka, Japan) using Fischer 344 rats (F344/DuCrlCrlj). These data were compared to the previous historical control data (from 1990 to 2004, previously reported) in the same facility. In the results, the incidence of C-cell adenoma in the thyroid tended to increase in both sexes in recent years (30.8% for males and 24.4% for females in 2005-2009) as compared with the previous data (17.4% and 20.1% for males and 11.5% and 11.8% for females in 1990–1999 and 2000–2004, respectively). In addition, the incidences of pancreatic islet cell adenoma in males and uterine adenocarcinoma tended to increase from around 2000 and remained high in recent years (incidences of islet cell adenoma in males of 10.5%, 17.1% and 20.5% in 1990–1999, 2000–2004 and 2005–2009; incidences of uterine adenocarcinoma of 3.3%, 12.0% and 13.5% in 1990–1999, 2000–2004 and 2005–2009, respectively). There was no apparent difference in the incidence of other tumors.  相似文献   
57.
Bovine colostral CD8-positive cells are potent IFN-gamma-producing cells   总被引:1,自引:1,他引:0  
IFN-gamma plays an important role in cellular immunity contributing to microorganism elimination. We have previously reported that bovine colostrum contains high levels of IFN-gamma as well as immunoglobulin. Lymphocytes are potent producers of IFN-gamma, so establishing the lymphocyte population in colostrum will help to identify the source of colostral cytokines. In this study, we used flow cytometric analysis to quantify the population of three types of lymphocytes found in colostrum; namely, CD4 (Th) cells, CD8 (cytotoxic T) cells, and gammadelta-T cells. We also quantified the concentration of colostral IFN-gamma using ELISA. IFN-gamma concentrations were measured in colostrum obtained from 96 healthy Holstein cows; the levels tended to decrease on the first day post-parturition. Flow cytometric analysis showed that many gammadelta-T- and CD8-positive cells were present in the colostrum, and that the CD4/CD8 ratio was low. The ratios of CD8- and gammadelta-T-positive cells to cells of other types decreased during the 5 days after parturition, but that of CD4-positive cells showed no change during the observation period. To identify IFN-gamma-expressing colostral lymphocytes, we used magnetic separation technology to separate the lymphocytes (CD4, CD8 and gammadelta-T) from colostral cells, then examined them for IFN-gamma mRNA expression with real-time PCR (RT-PCR). RT-PCR analysis revealed potent expression of the IFN-gamma gene in CD8-positive cells, reaching higher levels than in CD4- or gammadelta-T-positive cells. These results suggest that the CD8-positive T cells in colostrum play a role as producers of IFN-gamma.  相似文献   
58.
Tuna muscle often contains high levels of mercury, and fish samples with mercury concentrations ten times higher than the specified safety standards have been reported. Here, we report on the relationship between water temperature and the concentration of mercury in the tail muscle tissue of cultured bluefin tuna Thunnus orientalis. The fish used in this study were cultured at Fisheries Laboratory of Kinki University (Amami Experimental Station, Kagoshima, Japan). One hundred fish weighing 26.2–89.4 kg were selected for analysis between February 2007 and January 2008. Water temperature during rearing ranged from 21 to 29 °C. The total mercury levels were measured using the reduction vaporizing atomic absorption method after acid digestion. Body weight increased approximately 1.5 times that observed in a previous study, despite feeding activity either being the same or less than that observed previously. The average mercury concentration in white muscle was 0.353 mg kg?1, remaining almost constant and independent of body growth. Unlike previous studies, seasonality was not observed in this study. Based on these findings, water temperatures within a certain range were considered to stabilize feeding activity and increase feeding efficiency. Consequently, water temperature is considered to have a moderating effect on seasonal fluctuations in muscle mercury concentrations in cultured bluefin tuna.  相似文献   
59.
Overfishing has reduced the stock of hairtail Trichiurus japonicus around the Bungo Channel, Japan. To determine whether using larger bait in the trolling line fishery could avoid catching small/undersize hairtail, we developed and trialled a new large artificial bait (a soft plastic bait, 6 inches long). A traditional lure with natural bait (type-1), a new lure of the new artificial bait hook without natural bait (type-2), and a new lure with natural bait (type-3) were tested in fishing operations around the Bungo Channel. Compared with type-1, type-2 and type-3 caught fewer undersized and immature female individuals. The number of fish caught, yield, and composition of commercial size grades per recruitment were calculated from field data for each lure and compared. The catch sizes (number of fish per recruitment) were smaller for type-2 and type-3 than for type-1, but yield per recruitment was higher for type-3 than for type-1. Compared with type-1, type-2 and type-3 caught more large individuals, which are more valuable. The newly developed artificial bait conserves hairtail stocks by targeting larger fish, which is economically beneficial for the hairtail trolling line fishery.  相似文献   
60.
Fatty-acid esters of dinophysistoxin-1 (DTX1) in scallops Patinopecten yessoensis, mussels Mytilus coruscus, and toxic dinoflagellate Dinophysis species, collected from Japanese seawater, were analyzed by liquid-chromatography mass spectrometry (LC–MS). Precursor ion monitoring, multiple reaction monitoring for 18 fatty-acid esters of DTX1, and full-scan MS/MS spectra obtained with a hybrid triple–quadrupole linear-ion-trap mass spectrometer showed that 14:0, 16:0, and 16:1 esters were the most abundant 7-O-acyl-DTX1 analogues in bivalves. Fatty-acids esters formed by conjugations at hydroxyl positions other than the 7-position of DTX1 were not detected in the bivalves. DTX1 and okadaic acid-16:0 fatty-acid esters have been reported as the most abundant ester in bivalves in several previous studies; however, we found that 7-O-16:1-DTX1 was the most abundant ester in some mussels in which 16:1 was more dominant than 16:0 in the free fatty-acid profile. Comparison between 7-O-acyl-DTX1 and free fatty-acid profiles in the same bivalve samples suggests that polyunsaturated fatty acids are selectively excluded in enzymatic acylation of DTX1. No 7-O-acyl-DTX1 was detected in any single-cell isolates of D. fortii, D. acuminata, D. mitra, D. norvegica, D. tripos, D. infundibulus, and D. rotundata.  相似文献   
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