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1.
ABSTRACT:   A total of 110 adult individuals from four ommastrephid (family Ommastrephidae) squid species ( Ommastrephes bartramii, Sthenoteuthis oualaniensis, Eucleoteuthis luminosa, and Hyaloteuthis pelagica ) were used to obtain diagnostic DNA markers for species identification. Restriction fragment length polymorphism (RFLP) analysis of a partial segment (855 bp) of the mitochondrial DNA cytochrome oxidase I (COI) gene amplified by polymerase chain reaction (PCR) revealed that the restriction profiles of two endonucleases ( Alu  I and Tsp 509 I) were diagnostic for species identification. The restriction assay partially supplemented with nucleotide sequence analysis successfully assigned 69 damaged and morphologically equivocal ommastrephid paralarvae collected in northern Hawaiian waters, identifying 60 O. bartramii , eight S. oualaniensis , and one E. luminosa . The family Ommastrephidae appears to be monophyletic. Although the phylogenetic relationships among genera were not resolved well due to apparent homoplasy and large genetic divergence between species, COI sequence data without transitions provided support for subfamily level relationships.  相似文献   
2.
As IgE plays a pivotal role in type I hypersensitivity-mediated allergic diseases, it is valuable to measure absolute quantity of serum antigen-specific IgE for clinical and research purposes. Here we describe a novel ELISA system that enables quantification of antigen-specific IgE in ng/ml in dogs. A newly developed monoclonal antibody (CRE-DM) was shown to recognize canine and mouse IgE equally in a dose dependent manner, but it did not recognize canine IgG. The reactivity of CRE-DM to canine IgE was also confirmed by an inhibition ELISA using canine IgE as an inhibitor and the maximum inhibition rate was 91.3%. In order to know whether canine IgE specific to an allergen could be quantitatively measured with an ELISA using CRE-DM, we established a quantitative ELISA that could measure canine IgE recognizing Cry j 1, one of the major allergens of Japanese cedar pollen. In this ELISA, a standard curve was created by using concentration-predetermined Cry j 1-specific monoclonal mouse IgE. According to the standard curve, the concentration of Cry j 1-specific IgE in dogs that were experimentally sensitized to Japanese cedar pollen could be calculated and determined in ng/ml. The specificity of the Cry j 1-specific IgE ELISA using CRE-DM was also confirmed by inhibition ELISA using canine IgE as an inhibitor and the inhibition rate was 97.0%. Reproducibility of the ELISA in three independent assays was determined using groups of pooled canine sera whose Cry j 1-IgE titers ranged from 155.9 to 888.2 ng/ml. Intra- and inter-assay reproducibility was determined with coefficient of variation ranging between 3.1-5.2% and 2.2-8.0%, respectively. These results demonstrated that the ELISA utilizing CRE-DM was a specific, reliable and robust new laboratory test that could quantify absolute amount of antigen-specific IgE in canine serum. The ELISA will serve as a useful tool in the clinics to evaluate the change of serum IgE titers during anti-allergic treatments as well as during seasonal fluctuation of allergen exposure.  相似文献   
3.
The objective of this study was to evaluate the efficiency of gonadotropin releasing hormone (GnRH) and GnRH doses in synchronizing follicular wave emergence as a pretreatment for superovulation in cattle. Fourteen Holstein-Friesian cows 6 days from estrus were randomly assigned to receive 100 microg (n=4), 50 microg (n=5), or 25 microg (n=5) of GnRH. Superovulation was induced with injections of porcine FSH (pFSH) twice daily, decreasing the dose (total 42 AU) over 5 days beginning 2.5 days after receiving GnRH. On the 7th and 8th injections of pFSH, 750 microg of PGF(2alpha) was also given. With the exception of one cow that was given 50 microg of GnRH, ovulation was induced in all cows from the three groups and the new follicular wave emergence was observed. The total number of follicles for the 25 microg GnRH group was less than that observed for the 100 microg GnRH group (P<0.05), although there were no differences between the 100 microg, 50 microg and 25 microg GnRH groups with respect to the number of preovulatory follicles (>or=10 mm) and CL. The numbers of normal embryos were greater for the 25 microg GnRH group than the 100 or 50 microg GnRH groups (P<0.01); however, the numbers of ova/embryos did not differ significantly between the three groups. These results suggest that 25 microg of GnRH was sufficient to induce ovulation and follicular wave emergence. On day 6 of the estrous cycle, a reduction of the dose of GnRH to synchronize follicular wave emergence as a pretreatment for superstimulation promotes transferable embryos.  相似文献   
4.
Under the coastal fisheries co-management regime in Japan, local fishers play important roles in deciding on and implementing local management measures. Therefore, using the case study of a hairtail trolling line fishery, we conducted a transdisciplinary research with fishers, processors, government officers, etc. Taking social and biological factors into account, we defined management criteria and targets (resource, economic, human community, and local food culture) in collaboration with local fishers. We chartered local fishing vessels to determine parameters that were easily understood by local fishers. We established a local consultative committee comprising fishers, processors, and distributors, and developed a fish distribution strategy to nurture the local hairtail food culture. The integrated effects of various management scenarios were evaluated by the operating model. We found that co-ordinated management by both the trolling line fishery and purse seiners in the neighbouring prefecture was required to achieve targets. Two realistic scenarios are recommended: a conservative scenario that could achieve targets even with few strong year classes, and an adaptive scenario that protects strong year classes, but relies on a higher frequency of these. We shared these results with the local fishers and government officers, which led to actual improvements in management measures.  相似文献   
5.
We investigated the physicochemical properties of the thermal gel of water‐washed pork meat (WWM) in the presence of the soluble fraction of porcine sarcoplasmic protein (SP) obtained with ammonium sulfate at 75 percent saturation. Two precipitated fractions of SP were obtained at 0–50 percent and 50–75 percent saturation, named SP‐f1 and SP‐f2, respectively, and the soluble fraction obtained at 75 percent saturation, SP‐f3, was used. Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis showed that SP‐f3 contained mainly glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), while SP‐f1 and SP‐f2 had other SPs such as phosphorylase b, enolase, actin and phosphoglycerate mutase. The gel strength of WWM was greater when SP‐f3 rather than one of various animal proteins such as bovine plasma (BP), egg white, or whey protein isolates (WPI), was added and SP‐f3 had a gel‐enhancing effect as good as that of polyphosphate (PP). The gel strength of WWM with added SP‐f3 increased significantly with NaCl at 0.15 mol/L or more, but not in the absence of NaCl (0 mol/L). The effect of SP‐f3 was evident at neutral pH and maximum gel strength was obtained at a pH above 6.0. Differential scanning calorimetric (DSC) analysis showed that an endothermic peak corresponding to myosin heads in WWM shifted to a lower temperature with the addition of SP‐f3, as in the case of PP, though there was no such shift in the presence of other animal proteins (BP, egg white and WPI), suggesting that SP‐f3 increases the gel strength of WWM through the dissociation of actomyosin similar to PP. Scanning electron microscopy (SEM) revealed wall‐like structures among the protein strands in the WWM gel matrix in the presence of SP‐f3. The results of DSC and SEM indicated that the formation of a gel network in meat products is reinforced with GAPDH in SP after the interaction between GAPDH and myofibrillar protein.  相似文献   
6.
7.
Currently, antimicrobial-resistant staphylococci, particularly methicillin-resistant Staphylococcus pseudintermedius (MRSP), are frequently isolated from canine superficial pyoderma in Japan. However, little is known regarding the nasal prevalence of MRSP in pet dogs. Here, we determined the prevalence of antimicrobial-resistant staphylococci in nares and affected sites of pet dogs with superficial pyoderma. Of the 125 nares and 108 affected sites of pet dogs with superficial pyoderma, 107 (13 species) and 110 (eight species) staphylococci strains, respectively, were isolated. The isolation rate of S. pseudintermedius from pyoderma sites (82/110 strains, 74.5%) was significantly higher than that from nares (57/107 strains, 53.3%) (P<0.01). Notably, the prevalence of MRSP (18/57 strains, 31.6%) in nares was equivalent to that in pyoderma sites (28/82 strains, 34.1%). Furthermore, the phenotypes and genotypes of antimicrobial resistance in MRSP strains from nares were similar to those from pyoderma sites. Our findings revealed that the prevalence of antimicrobial-resistant staphylococci in the nares of pet dogs with superficial pyoderma is the same level as that in affected sites. Therefore, considerable attention should be paid to the antimicrobial resistance of commensal staphylococci in companion animals.  相似文献   
8.
This study examined the effects of feeding water-soluble soybean fiber (WSSF), a highly fermentable dietary fiber with low viscosity, on intestinal calcium (Ca) absorption, bone mineral content, and serum total cholesterol levels using female Sprague-Dawley rats (5 weeks old) with or without ovariectomy (OVX). The rats in each group were fed a WSSF (50 g/kg of diet) or WSSF-free diet for 4 weeks. Ca absorption was higher in OVX rats fed the WSSF diet than in OVX rats fed the WSSF-free diet. Femoral Ca content in both sham and OVX rats fed the WSSF diet was higher than that in rats fed the WSSF-free diet. The serum total cholesterol levels were elevated after OVX compared with that in the sham rats, and this elevation was prevented by the WSSF diet. In conclusion, ingestion of WSSF prevented osteopenia and hypercholesterolemia induced by ovariectomy in rats.  相似文献   
9.
Magnetic reconnection of solar coronal loops is the main process that causes solar flares and possibly coronal heating. In the standard model, magnetic field lines break and reconnect instantaneously at places where the field mapping is discontinuous. However, another mode may operate where the magnetic field mapping is continuous but shows steep gradients: The field lines may slip across each other. Soft x-ray observations of fast bidirectional motions of coronal loops, observed by the Hinode spacecraft, support the existence of this slipping magnetic reconnection regime in the Sun's corona. This basic process should be considered when interpreting reconnection, both on the Sun and in laboratory-based plasma experiments.  相似文献   
10.
Excessive stress response causes disability in social life. There are many diseases caused by stress, such as gastrointestinal motility disorders, depression, eating disorders, and cardiovascular diseases. Transient receptor potential (TRP) channels underlie non-selective cation currents and are downstream effectors of G protein-coupled receptors. Ca2+ influx is important for smooth muscle contraction, which is responsible for gastrointestinal motility. Little is known about the possible involvement of TRP channels in the gastrointestinal motility disorders due to stress. The purpose of this study was to measure the changes in gastrointestinal motility caused by stress and to elucidate the mechanism of these changes. The stress model used the water immersion restraint stress. Gastrointestinal motility, especially the ileum, was recorded responses to electric field stimulation (EFS) by isometric transducer. EFS-induced contraction was significantly reduced in the ileum of stressed mouse. Even under the conditions treated with atropine, EFS-induced contraction was significantly reduced in the ileum of stressed mouse. In addition, carbachol-induced, neurokinin A-induced, and substance P-induced contractions were all significantly reduced in the ileum of stressed mouse. Furthermore, the expression of TRPC3 was decreased in the ileum of stressed mouse. These results suggest that the gastrointestinal motility disorders due to stress is associated with specific non-selective cation channel.  相似文献   
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