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31.
In a roasted Arabica coffee brew, the potent roasty odor quality compound was identified as 3-mercapto-3-methylbutyl acetate by comparison of its Kovats gas chromatography retention index, mass spectrum, and odor quality to those of the synthetic authentic compound. 3-Mercapto-3-methylbutyl acetate has been identified for the first time in the coffee, and according to the results of the aroma extract dilution analysis, the contribution of this compound to the flavor of the roasted coffee brew varied depending on the degree of the coffee bean roasting. The concentration of this compound in the coffee brews as with 3-mercapto-3-methylbutyl formate increased with an increase in the degree of roasting. However, the slope of the amount of both esters was different, and 3-mercapto-3-methylbutyl acetate hardly increased with a low degree of roasting at more than a 21 luminosity (L)-value, but it rapidly increased when the roasting degree of the coffee beans reached the L-value of 18. These results suggested that the contribution of 3-mercapto-3-methylbutyl acetate to the overall flavor is peculiar to the flavor of the highly roasted coffee. 相似文献
32.
A Setoguchi M Okuda E Nishida M Yazawa T Ishizaka S H Hong M Hisasue R Nishimura N Sasaki Y Yoshikawa K Masuda K Ohno H Tsujimoto 《American journal of veterinary research》2001,62(7):1134-1141
OBJECTIVE: To evaluate results of centrosome hyperamplification in naturally developing tumors of dogs. SAMPLE POPULATION: Tumor specimens from 9 dogs with tumors (rhabdomyosarcoma, osteosarcoma, chondrosarcoma, myxosarcoma, and mammary gland tumor) and 2 canine osteosarcoma cell lines. PROCEDURE: 3 antibodies for centrosome proteins (ie, anti-gamma-tubulin, anti-BRCA1, and anti-pericentrin) were used for immunohistochemical analysis. Double immunostaining for centrosomes was used to confirm the specificity of these antibodies for centrosomes. Mutational analysis of the canine p53 gene was carried out by polymerase chain reaction-single-strand conformation polymorphism analysis, and expression of canine MDM2 protein was evaluated by use of immunohistochemical analysis, using anti-MDM2 antibody. RESULTS: Immunohistochemical analysis of dog osteosarcoma cell lines with apparent aneuploidy revealed frequent hyperamplification of centrosomes in the osteosarcoma cell lines. Similar hyperamplified centrosomes were detected in the tumor tissues from all of the 9 tumors. The frequency of cells with hyperamplified centrosomes (3 to 20/cell) in each tumor tissue ranged from 9.50 to 48.1%, whereas centrosome hyperamplification was not observed in normal lymph nodes from these dogs. In 8 of the 9 tumors, mutation of p53 gene or overexpression of MDM2, or both, was detected. CONCLUSIONS AND CLINICAL RELEVANCE: Various types of naturally developing tumors in dogs often have hyperamplification of centrosomes associated with chromosome instability. Hyperamplification of centrosomes is a novel tumor marker for use in cytologic and histologic examinations of clinical specimens obtained from dogs. 相似文献
33.
Ethylene (C2H4) applied before chilling stimulated rooting and sprouting, and increased root number and length per corm. Only when corms experienced high temperature for a certain period before or after C2H4 treatment was a promotive effect on sprouting observed. When C2H4 was applied at the beginning of the high-temperature storage, the effect was greatest and all treated corms sprouted within 2 weeks of planting. Effects of ethephon on sprouting were slight.Shortening the dormant period with C2H4 could be useful for practical freesia forcing, since C2H4 has no adverse effects on the development of the root and the shoot. 相似文献
34.
Ghanem ME Nishibori M Nakao T Moriyoshi M 《The Journal of reproduction and development》2005,51(3):347-352
Genomic DNA extracted from bovine mummified tissue is valuable material for detection of some genes that may contribute to fetal abnormalities. In this study bovine genomic DNA was extracted from the hardened tissue samples of ten bovine mummified fetuses. The amount of genomic DNA extracted from 2 g of the mummified tissues by the phenol/chloroform-ethanol method was low (less than 4 microg/ml) for all samples. The extracted DNA was then amplified by the GenomiPhi DNA amplification system. After amplification, the amount of DNA was increased to more than 100 microg/ml for all samples. This amplification system was shown to be a good tool for amplifying the genomic DNA of the mummified fetuses. The amplified genomic DNA was used for testing the mummies for Factor XI gene deficiency, an autosomal recessive deficiency involved in the early stages of the intrinsic blood coagulation pathway. Exon 12 of the Factor XI gene of the mummies was amplified by PCR. Two of the ten mummified fetuses were heterozygous for the Factor XI gene as indicated by the presence of two amplified DNA fragments of 320 bp and 244 bp. Factor XI deficiency has already been described in Holstein cattle. However, no report is available for bovine fetus. In this study, DNA was extracted and amplified from the bovine mummified fetuses, and the samples were successfully tested for Factor XI gene deficiency in the mummies. 相似文献
35.
Ishida R Masuda K Kurata K Ohno K Tsujimoto H 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2004,18(1):25-30
Lymphocyte blastogenic responses against food allergens in dogs with food hypersensitivity were evaluated in this study. Eleven dogs with food hypersensitivity, based on food elimination and oral food provocation tests and allergic responses to food allergens, were examined by various tests such as intradermal testing, antigen-specific IgE testing, and lymphocyte blastogenic responses. The number and kinds of food allergens identified as positive by these tests were compared with the offending food allergens that were found in an oral food provocation test. In 9 (82%) of the 11 dogs with food hypersensitivity, there was close agreement for positive allergens between the results of lymphocyte blastogenic responses and oral food provocation test; however, there was little agreement for intradermal and IgE testing of the positive allergens with those of the oral food provocation test (11% and 31%, respectively). In the 9 dogs, the stimulation indices of lymphocyte blastogenic responses increased to 2.0-10.1 upon food provocation but decreased significantly to 0.7-1.4 upon feeding the elimination diet until clinical signs disappeared. These results indicate that lymphocyte blastogenic responses may fluctuate because of exposure to offending food allergens in dogs with food hypersensitivity. Lymphocytes reactive to food allergens may play an important role in the pathogenesis of food hypersensitivity in dogs. 相似文献
36.
Kurata K Iwata A Masuda K Sakaguchi M Ohno K Tsujimoto H 《Veterinary immunology and immunopathology》2004,102(4):441-450
Oligodeoxynucleotides containing the cytosine-phosphate-guanine (CpG) motif (CpG-ODNs) have been shown to induce T(H)1 immune responses in animals. Since the sequences of CpG-ODNs that induce T(H)1 responses are considered to vary among animal species, it is necessary to identify effective CpG-ODNs in each animal. In order to identify the sequences of CpG-ODNs that induce T(H)1 responses in dogs, mRNA expression and protein production of IFN-gamma were examined in peripheral blood mononuclear cells (PBMCs) from healthy dogs treated with 11 kinds of synthetic CpG-ODNs. One of the 11 CpG-ODNs (No. 2 CpG-ODN, 5'-GGTGCATCGATGCAGGGGGG-3') was shown to significantly increase mRNA expression and protein production of IFN-gamma in canine PBMCs in a manner dependent on the sequence of the CpG motif. This CpG-ODN also enhanced the expression of IL-12 p40 mRNA in canine PBMCs, whereas expression of IL-12 p35, IL-18, and IL-4 mRNAs was not induced by this CpG-ODN. These results indicate that this CpG-ODN was able to produce IFN-gamma by induction of T(H)1-skewed immune response in dogs. CpG-ODNs may be useful for inducing prophylactic and therapeutic immunity against allergic diseases, viral infection, and tumors in dogs. 相似文献
37.
In a black tea (Dimbula) infusion, the potent "sweet and/or juicy" odorants were identified as the cis- and trans-4,5-epoxy-(E)-2-decenals by comparison of their gas chromatography retention indices, mass spectra, and odor quality to those of the actual synthetic compounds. Of the two odorants, cis-4,5-epoxy-(E)-2-decenal has been identified for the first time in the black tea. On the basis of the aroma extract dilution analysis on the flavor distillate obtained using the solvent-assisted flavor evaporation technique from the black tea infusion, these isomers showed higher flavor dilution (FD) factors. The FD factors and concentrations of these odorants in the black tea infusion were observed to be much higher than those from Japanese green tea. In addition, the model studies showed that these odorants were generated from linoleic acid and its hydroperoxides by heating, but the generated amounts of these odorants from linoleic acid were much less than those of its hydroperoxides. It can be assumed from these results that the withering and fermentation, which are characteristic processes during the manufacturing of the black tea, which includes the enzymatic reaction such as lipoxygenase, is one of the most important factors for the formation of the epoxydecenal isomers. 相似文献
38.
Ogata N Hashizume C Momozawa Y Masuda K Kikusui T Takeuchi Y Mori Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(2):157-159
Excitatory amino acid transporters (EAATs) are important for terminating glutamatergic neurotransmission and protect central nervous system (CNS) neurons from glutamatergic excitotoxicity. We selected these genes as targets that may relate to canine behavioral traits. After screening four EAAT genes (glutamate transporter-1; GLT-1, excitatory amino acid transporter 4; EAAT4, excitatory amino acid carrier; EAAC1, glutamate/aspartate transporter; GLAST) for single nucleotide polymorphisms (SNPs), we identified two silent SNPs (C129T and T471C) in the GLT-1 gene. We genotyped 193 dogs of 5 breeds and found significant variation among breeds in these two SNPs in GLT-1. The C129T polymorphism was not observed in Malteses and Miniature Schnauzers. These results suggest that polymorphisms in the GLT-1 gene may be useful markers for examining how the genetic background relates to the behavioral traits of dogs. 相似文献
39.
Identification of Card15/Nod2 mRNA in intestinal tissue of experimentally induced colitis in rats 总被引:1,自引:0,他引:1
Fujisawa M Kiyosue M Hori M Ozaki H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(7):701-708
Card15/Nod2 has been suggested to be an intracellular pathogen-associated molecular pattern (PAMPs) recognition molecule, which contains a leucine-rich repeat region similar to the Toll-like receptors (TLRs). Card15/Nod2 gene variants play an important role in the susceptibility to Crohn's disease. In this study, we examined the kinetics of Card15/Nod2 expression in intestinal tissue during inflammation in the 2, 4, 6-trinitrobenzenesulfonic acid (TNBS)-treated rat experimental colitis model. At 2 and 4 days after TNBS administration, the mononuclear cells remarkably infiltrated the mucosal layer and tunica muscularis, which was followed by a gradual decrease to resting levels at 14 days after TNBS administration. Card15/Nod2 mRNA expression increased and peaked at 4 days after the TNBS administration, followed by a gradual decrease in accordance with the amelioration of the inflammatory response. Expressions of Tlr2, Tlr4 and Myd88 were also upregulated in the inflamed colonic region, and in an in situ hybridization study, a positive signal for Card15/Nod2 was observed in the crypt of the epithelial cell layer and in the infiltrated cells of the submucosal and myenteric regions. These results suggest that in addition to the TLR recognition systems, Card15/Nod2 may contribute to the inflammatory process not only in the epithelial and submucosal layers but also in the tunica muscularis. 相似文献
40.