Inhibition of juvenile hormone biosynthesis and methyl farnesoate epoxidase activity by 1,5-disubstituted imidazoles in the cockroach,Diploptera punctata     

Gopalan C. Unnithan  John F. Andersen  Tomomi Hisano  Eiichi Kuwano  Ren Feyereisen 《Pest management science》1995,43(1):13-19

Seventeen substituted imidazoles were tested as inhibitors of juvenile hormone (JH) III synthesis by cockroach corpora allata in an in-vitro radio-chemical assay. Most of these 1,5-disubstituted imidazoles were highly potent, with IC₅₀ values of less than 100nM. The compounds differed in their ability to cause an accumulation of the precursor methyl farnesoate in the glands. Four of the imidazoles were tested by topical application to previtellogenic adult females, and all caused a significant inhibition of JH synthesis and an accumulation of intraglandular methyl farnesoate for at least three days after treatment. Methyl farnesoate epoxidase activity of homogenates of corpora allata was inhibited by the compounds TH -14 and TH -27. This P450-dependent epoxidase activity was inhibited at less than 10 nM. The results show that the 1,5-disubstituted imidazoles are powerful inhibitors of the last step of juvenile synthesis in this cockroach.  相似文献   

Electron-microscope characterization of infectious bursal disease virus   总被引：1，自引：0，他引：1  

K Hirai  S Shimakura  E Kawamoto 《Avian diseases》1974,18(3):467-471

  相似文献   

Histological observation of the proper gastric gland in Minke whale,Balaenoptera acutorostrata     

Shimokawa T  Yamagiwa D  Hondo E  Nishiwaki S  Kiso Y  Makita T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(3):423-426

To accumulate histological information of cetaceans, the proper gastric gland of Minke whales was examined by light and electron microscopic observation. A small number of mucous neck cells and a large number of chief and parietal cells were observed in the gland. At the body to basal portions of the gland, the ratio of chief cells to other cells seemed to be large compared to the neck portion. Transmission electron microscopy revealed that the chief cell had secretory granules with middle level of electron density, and that the parietal cell contained abundant mitochondria and intracellular canaliculi. The proper gastric gland of the Minke whales may appear to secrete large amounts of digestive enzymes and have high digestive activity.  相似文献   

Intratubal insemination with fresh semen in dogs     

Tsutsui T  Hori T  Yamada A  Kirihara N  Kawakami E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(5):659-661

The number of spermatozoa required to obtain conception by intratubal insemination in dogs was examined. Three groups consisting of 5, 8 and 8 dogs received 0.5 x 10 (6), 2.0 x 10(6) and 4.0 x 10(6) spermatozoa, respectively, into each uterine tube. No conception occurred in the 5 animals inseminated with 0.5 x 10(6) spermatozoa, but conception occurred in 6/8 (75.0%) and 3/8 (37.5%) dogs inseminated with 2.0 x 10(6) and 4.0 x 10 (6) spermatozoa, respectively. Among the pregnant animals, three aborted (33.3%) and the mean number of newborns was small, 2.5 +/- 0.5 (SE). One acardiacus anceps was observed with normal fetus in one animal with a Caesarean delivery.  相似文献   

In vitro characterization of the inhibitory effects of ketoconazole on metabolic activities of cytochrome P-450 in canine hepatic microsomes     

Kuroha M  Kuze Y  Shimoda M  Kokue E 《American journal of veterinary research》2002,63(6):900-905

OBJECTIVE: To evaluate the inhibitory potency of ketoconazole (KTZ) on the metabolic activities of isozymes of cytochrome P-450 (CYP) in dogs. ANIMALS: 4 healthy 1-year-old male Beagles. PROCEDURE: Hepatic microsomes were harvested from 4 dogs after euthanasia. To investigate the effects of KTZ on CYP metabolic activities, 7-ethoxyresorufin, tolbutamide, bufuralol, and midazolam hydrochloride were used as specific substrates for CYP1A1/2, CYP2C21, CYP2D15, and CYP3A12, respectively. The concentrations of metabolites formed by CYP were measured by high-performance liquid chromatography, except for the resorufin concentrations that were measured by a fluorometric method. The reaction velocity-substrate concentration data were analyzed to obtain kinetic variables, including maximum reaction velocity, Michaelis-Menten constant, and inhibitory constant (Ki). RESULTS: KTZ competitively inhibited 7-ethoxyresorufin O-deethylation and midazolam 4-hydroxylation; it noncompetitively inhibited tolbutamide methylhydroxylation. Bufuralol 1'-hydroxylation was inhibited slightly by KTZ. The mean Ki values of KTZ were 10.6+/-6.0, 170+/-2.5, and 0.180+/-0.131 microM for 7-ethoxyresorufin O-deethylation, tolbutamide methylhydroxylation, and midazolam 4-hydroxylation, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: In dogs, KTZ at a therapeutic dose may change the pharmacokinetics of CYP3A12 substrates as a result of inhibition of their biotransformation. Furthermore, no influence of KTZ on the pharmacokinetics of CYP1A1/2, CYP2C21, and CYP2D15 substrates are likely. In clinical practice, adverse drug effects may develop when KTZ is administered concomitantly with a drug that is primarily metabolized by CYP3A12.  相似文献   

Lectin-binding characteristics and capacitation of canine epididymal spermatozoa   总被引：2，自引：0，他引：2  

Kawakami E  Morita Y  Hori T  Tsutsui T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(7):543-549

Cross sections of the testes and the caput, corpus and cauda epididymides removed from 12 dogs were stamped on glass slides, and the sperm on the slides were stained with 6 different FITC-lectins (Con A, DBA, PNA, PSA, SBA, and WGA) to examine the characteristics of the surface glycoproteins (GPs) on canine epididymal sperm. The corpus epididymal sperm were washed three times by centrifugation, and their lectin-binding characteristics were investigated. The washed sperm from the corpus and cauda epididymides were incubated for 24 hr, and the fertilizing capacity of the sperm was evaluated by calculating the percentages of actively motile sperm (%MO), hyperactivated sperm (%HA), and acrosome-reacted sperm (%AR), and the number of canine zona-pellucida (ZP)-binding sperm. The testicular sperm did not stain with SBA lectin, but the SBA lectin fluorescence was observed on the surface of the entire heads of the caput epididymal sperm. Although all of the entire heads or acrosomal regions of the corpus epididymal sperm stained with all 6 FITC-lectins, the heads and acrosomal regions of the cauda epididymal sperm did not stain with DBA or SBA lectins. Washing the sperm from the corpus epididymis resulted in loss of the fluorescence of the FITC-DBA and -SBA lectins. The mean %MO, %HA, %AR, and ZP-binding number of the cauda epididymal sperm after 24 hr of incubation were higher than the values for the corpus epididymal sperm. All of the mean values for the washed sperm from the corpus and cauda epididymides were higher than the values for the unwashed sperm from the corpus and cauda, and with the exception of %AR, the values from the washed sperm from the corpus epididymis were significantly higher (P<0.05, 0.01). The results indicate that DBA- and SBA-lectin-binding GPs on the surface of canine epididymal sperm are associated with the fertilizing capacity and may be decapacitation factors.  相似文献   

Factors affecting transuterine migration of canine embryos     

Tsutsui T  Shimizu T  Hori T  Kawakami E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(12):1117-1121

Dogs, cats, and pigs have a bicornuate uterus, and transuterine migration of embryos occurs in 40% or more of pregnant animals. However, the mechanism of the transuterine migration has not been elucidated in dogs. Thus, we investigated the occurrence of transuterine migration of embryos when embryos were retained in an unilateral uterine tube with more ovulated ova (Experiment 1), when one ovary was excised (Experiment 2), and when ova ovulated from the right and left ovaries were fertilized with sperm from male dogs with different blood types (Experiment 3). Transuterine migration of embryos was observed in 7/8 (87.5%), 10/10 (100%), and 11/17 (67.4%) fertilized animals in Experiments 1, 2, and 3, respectively. In Experiment 3, intrauterine embryo mixing reported in pigs did not occur. These findings suggest that transuterine migration of embryos occurs due to the number of embryos that enter the uterus but that differences in the number of ovulated ova between the right and left ovaries or the number of embryos retained in the uterine tube do not affect the migration.  相似文献   

Sympatric distribution of the two morphological types of the common tree shrew in Hat-Yai districts (South Thailand)     

Endo H  Hayashi Y  Rerkamnuaychoke W  Nadee N  Nabhitabhata J  Kawamoto Y  Hirai H  Kimura J  Nishida T  Yamada J 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(7):759-761

The two color types (grayish northern and reddish southern types) of the common tree shrew (Tupaia glis and Tupaia belangeri) were co-distributed in Hat-Yai region (South Thailand). Although the Isthmus of Kra in South Thailand has been considered as distribution barrier of the two types, the sympatric distribution of both types was confirmed in southern side of the Isthmus. In the principal component analysis, the skull measurement character from Hat-Yai region could also be separated into the northern and southern groups according to the skin color identification of corresponding individuals. We could generally distinguish the common tree shrew into two types by skull morphology as well as external skin color.  相似文献   

Confirmation of nitrogen fixation in two tropical grasses by ¹⁵N₂ incorporation     

Helvécio De-Polli  Eiichi Matsui  Johanna D?bereiner  Eneas Salati 《Soil biology & biochemistry》1977,9(2):119-123

Intact soil cores containing plants of Paspalum notatum or Digitaria decumbens were selected with the acetylene reduction method, and then exposed to ¹⁵N₁₅ to confirm nitrogen fixation in tropical grass-bacteria associations. In a preliminary experiment with P. notatum¹⁵N₂ incorporation was slow but progressive during 24 h in roots but translocation to rhizomes and leaves ceased after 17h. With improved assay chambers, enrichments of 0.151 and 0.563 ¹⁵N atom % excess were obtained in roots of D. decumbens cv transvala and P. notatum systems respectively, after 3 days. Enrichments in rhizomes were similar to those of roots; however in the leaves only 8% of root enrichment was observed. The addition of sucrose to the soil doubled N₂-fixation in roots in both grass species studied, but did not result in increased incorporation into the leaves of P. notatum.  相似文献   

Reaction behavior of lignin in supercritical methanol as studied with lignin model compounds   总被引：2，自引：0，他引：2  

E.?Minami  H.?Kawamoto  S.?SakaEmail author 《Journal of Wood Science》2003,49(2):158-165

 The reaction behavior and kinetics of lignin model compounds were studied in supercritical methanol with a batch-type supercritical biomass conversion system. Guaiacol, veratrole, 2,6-dimethoxyphenol, and 1,2,3-trimethoxybenzene were used as model compounds for aromatic rings in lignin. In addition, 5-5, β-1, β-O-4, and α-O-4 types of dimeric lignin model compounds were used as representatives of linkages in lignin. As a result, aromatic rings and 5-5 (biphenyl)-type structures were stable in supercritical methanol, and the β-1 linkage was not cleaved in the β-1-type structure but converted rapidly to stilbene. On the other hand, β-ether and α-ether linkages of β-O-4 and α-O-4 lignin model compounds were cleaved rapidly, and these compounds decomposed to some monomeric compounds. Phenolic compounds were found to be more reactive than nonphenolic compounds. These results indicate that cleavages of ether linkages mainly contribute to the depolymerization of lignin, whereas condensed linkages such as the 5-5 and β-1 types are not cleaved in supercritical methanol. Therefore, it is suggested that the supercritical methanol treatment effectively depolymerizes lignin into the lower-molecular-weight products as a methanol-soluble portion mainly by cleavage of the β-ether structure, which is the dominant linkage in lignin. Received: December 19, 2001 / Accepted: April 30, 2002 Acknowledgments This research has been done under the research program for the development of technologies for establishing an ecosystem based on recycling in rural villages for the twenty-first century from the Ministry of Agriculture, Forestry and Fisheries, Japan; by a Grant-in-Aid for Scientific Research (B)(2) (no.12460144, 2001.4–2003.3) from the Ministry of Education, Culture, Sports, Science and Technology, Japan; and under the research program from Kansai Research Foundation for Technology Promotion, Japan. The authors thank them for their financial support. This study was presented in part at the 45th Lignin Symposium, Ehime, Japan, October 2000 and the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, Japan, April 2002 Correspondence to:S. Saka  相似文献