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61.
The female sex hormone estrogen exerts anti‐inflammatory effects. The G‐protein‐coupled estrogen receptor (GPER) has been recently identified as a novel membrane‐type estrogen receptor that can mediate non‐genomic estrogenic effects on many cell types. We previously demonstrated that GPER inhibits tumor necrosis factor alpha‐induced expression of interleukin 6 (IL‐6) through repression of nuclear factor‐kappa B (NF‐κB) promoter activity using human breast cancer cells. Although several reports have indicated that GPER suppresses Toll‐like receptor‐induced inflammatory cytokine expression in macrophages, the molecular mechanisms of the inhibition of cytokine production via GPER remain poorly understood. In the present study, we examined GPER‐mediated inhibition of IL‐6 expression induced by lipopolysaccharide (LPS) stimulation in a mouse macrophage cell line. We found that the GPER agonist G‐1 inhibited LPS‐induced IL‐6 expression in macrophage cells, and this inhibition was due to the repression of NF‐κB promoter activity by GPER. G‐1 treatment also decreased the phosphorylation of inhibitor of κB kinases. Among the mitogen‐activated protein kinases, the phosphorylation of c‐jun N‐terminal kinase (JNK) was increased by G‐1. These findings delineate the novel mechanism of the inhibition of LPS‐induced IL‐6 through GPER‐activated JNK‐mediated negative regulation of the NF‐κB pathway in murine macrophage cells, which links anti‐inflammatory effects to estrogen.  相似文献   
62.
The Djungarian hamster and the Roborovskii hamster belong to the same genus of Phodopus. However, the Djungarian hamster is tame and shows sedative behavior, while Roborovskii hamster is not tame and shows high levels of locomotor activity. Hyperactivity occurs in animals with tameless behavior. Tameness or tamelessness behavior is very important because tameness helps for breeding and controlling as well as it enables a strong human‐animal bond. In the present study, we examined the relationships between activity levels and cognitive function in Djungarian and Roborovskii hamsters. Three types of behavioral tests were performed to analyze their activity levels, memory and leaning ability. The levels of L‐ and D‐amino acids and monoamines in the brain were then determined. Roborovskii hamsters showed significantly higher locomotor activity than Djungarian hamsters. Memory ability was not significantly different between the two hamsters, but Roborovskii hamsters showed lower learning ability. Brain levels of D‐serine which is related to enhancement in memory and learning ability, were significantly higher in Djungarian hamsters, but the reverse was true for brain dopamine and serotonin levels. These results suggest that these differences in brain metabolism may be related to the behavioral differences between the two hamsters.  相似文献   
63.
Data from 18 β‐carotene‐deficient Japanese Black cows were collected to clarify the effects of feeding β‐carotene‐enriched dry carrots on β‐carotene status and colostral immunoglobulin (Ig) in cows. Cows were assigned to control or carrot groups from 3 weeks before the expected calving date to parturition, and supplemental β‐carotene from dry carrots was 138 mg/day in the carrot group. Plasma β‐carotene concentrations in the control and carrot groups at parturition were 95 and 120 μg/dL, and feeding dry carrots slightly improved plasma β‐carotene at parturition. Feeding dry carrots increased colostral IgA concentrations in cows and tended to increase colostral IgG1, but colostral IgM, IgG2, β‐carotene and vitamin A were not affected by the treatment. Feeding dry carrots had no effects on plasma IgG1, IgA and IgM concentrations in cows, but plasma IgG1 concentrations decreased rapidly from 3 weeks before the expected calving date to parturition. These results indicate that feeding β‐carotene‐enriched dry carrots is effective to enhance colostral IgA and IgG1 concentrations in β‐carotene‐deficient cows.  相似文献   
64.
Pepper (Piper nigrum L.) root rot caused by Fusarium solani f. sp. piperis (FSP; teleomorph: Nectria haematococca f. sp. piperis) includes two symptom types called root rot (RR) type and stem rot (SR) type. In this study, the temporal and spatial associations between perithecial formation of FSP and development of SR were investigated in naturally infested fields to verify the hypothesis that ascospores from the perithecia are the major inoculum source of the SR type on vines in the field. In surveys of all vines in two neighboring pepper fields every month from December 2005 to November 2006, I mapped the locations of all vines with perithecia and all vines the SR type. The frequency of vines with perithecia increased during April and May, the late rainy season. In June, the early dry season, the number of vines with SR type greatly increased. The vertical range of perithecial formation on the vines extended to 200 cm in height, but was restricted to 30 cm in the dry season in both fields. The join-count statistics showed a significant spatial association between vines with perithecia and vines with SR type in one field (P = 0.042), while no significant spatial association was recognized in another field. The results suggested that ascospores from perithecia of FSP on pepper vines are likely to be one of the main inoculum sources of the SR type of the disease on adjacent vines, but they may not be the exclusive source.  相似文献   
65.
A 15‐year‐old, spayed, female poodle dog was presented for evaluation of a mass of tissue prolapsed from the vulva. The dog had been hysterectomized when it was 5 years old. A vaginal mass had been removed approximately 10 months before presentation. Haematological and serum biochemistry analyses demonstrated mild leucocytosis and glycaemia. A vaginal smear was predominantly made up of parabasal cells and intermediate cells with no neoplastic cells. Thoracal and abdominal radiographic findings were unremarkable. The ovaries could not be identified using abdominal ultrasonography. A midline exploratory laparotomy identified both ovaries that were surgically excised. The vaginal mass was also removed following an episiotomy procedure. Histopathological examination of the mass demonstrated that it was a neurofibroma. Both ovaries had cystic changes. Four months after the surgery, the owner reported that the dog was clinically normal. To the authors’ knowledge, this is the first reported case of a vaginal neurofibroma after an incomplete ovariohysterectomy in the dog.  相似文献   
66.
67.
Schoenoplectus juncoides, a noxious weed for paddy rice, is known to become resistant to sulfonylurea (SU) herbicides by a target-site mutation in either of the two acetolactate synthase (ALS) genes (ALS1 and ALS2). SU-resistant S. juncoides plants having an Asp376Glu mutation in ALS2 were found from a paddy rice field in Japan, but their resistance profile has not been quantitatively investigated. In this study, dose–response of the SU-resistant accession was compared with that of a SU-susceptible accession at in vivo whole-plant level as well as at in vitro enzymatic level.  相似文献   
68.
It is known that pica, the consumption of non-nutritive substances such as kaolin, can be induced by administration of toxins or emetic agents in rats. In the present study, we examined the effects of intraperitoneal (i.p.) administration of cyclophosphamide on pica behavior and on the concentration of 5-hydroxyindoleacetic acids (5HIAA) in cerebrospinal fluid (CSF) in the following five strains of adult male rats: Sprague Dawley (SD), Wistar, Fischer 344 (F344), Wistar-Imamichi (WI) and Long Evans (LE). Cyclophosphamide (25 mg or 50 mg/kg) was injected (i.p.) into the rats and kaolin and food intake were measured at 24 hr after injection. The animals were anesthetized with urethane (1 g/kg) at 3 hr after injection of cyclophosphamide, and CSF was collected from the cisterna magna. WI and LE rats clearly showed pica behavior as compared with the other strains. In LE rats, the concentration of 5HIAA in CSF also increased in a dose-dependent manner of cyclophosphamide. The pretreatment with ondansetron (5-HT(3) antagonist) restored both changes (kaolin consumption and 5HIAA levels) induced by cyclophosphamide. These results suggest that the LE rat is sensitive to cyclophosphamide, that pica induced by cyclophosphamide mimics many aspects of emesis including the serotonergic response in the central nervous system and that use of the pica model would be a practical method for evaluating the effects of antiemetic drugs in addition to the mechanism of emesis.  相似文献   
69.
Canine Visceral Leishmaniasis (CVL) is a widespread zoonotic disease with mandatory euthanasia of infected dogs determined by the Brazilian Ministry of Health. Development of vaccines against CVL may provide a prophylactic barrier, but transitory peak of antibody response detected by standard diagnostic techniques in vaccinated dogs may be interpreted as natural infection. Accordingly, the aim of the present study was to sequentially evaluate total and IgG subclasses response between naturally Leishmania-infected and dogs vaccinated with Leishmune(?). A total of 172 mongrel dogs were divided in four groups: Group 1 (G1) with 45 clinically healthy dogs, Group 2 (G2) and Group 3 (G3) with 45 dogs naturally infected by Leishmania sp. each, symptomatic and asymptomatic respectively, and G4 (G4) with 37 healthy dogs submitted to a complete protocol of a commercially available vaccine against CVL, monitored and evaluated in 5 different chronological moments (M0-M4) up to 180 days after M0. Total IgG, IgG1 and IgG2 were unable to differentiate between infected (G2 and G3) and vaccinated (G4) dogs, demonstrating that polyclonal commercial antibodies do not distinguish these groups apart. Total and IgG subclasses antibodies were not detected until 21 days of the second vaccination dose; however, seroconversion was observed on 21 days and sustained positivity up to 6 months after the vaccination start. A peak of antibodies response was observed on 90 days (M3), when results for total IgG, IgG1, IgG2, IgG3 and IgG4 where highly significant when compared to M0 (P<0.0001). Neither total IgG nor IgG1 effectively differentiated between infected (G2 and G3) and vaccinated (G4) dogs. In conclusion, despite dogs may test serologically negative immediately after vaccination against CVL with Leishmune(?), subsequent seroconversion, antibody peak and positivity up to six months may lead vaccinated dogs to be mistakenly identified as naturally infected dogs during this period.  相似文献   
70.
Because foam cell formation in macrophages is believed to play an essential role in the progression of early atherosclerotic lesions in vivo, prevention of foam cell formation is considered to be one of the major targets for the treatment of atherosclerosis. The present study examined the inhibitory effect of 50 crude plant extracts on foam cell formation. Among those crude extracts, Zizyphi Fructus (ZF) and Zizyphi Semen (ZS) extracts significantly inhibited the foam cell formation induced by acetylated LDL. Furthermore, triterpenoids such as oleanonic acid, pomolic acid, and pomonic acid were the major active compounds, and triterpenoids containing a carboxylic acid at C-28 play an important role in the inhibitory effect on foam cell formation in human macrophages. These data suggest that triterpenoids in Zizyphus jujuba , the plant source of ZF and ZS, may therefore be useful for the prevention of atherosclerosis.  相似文献   
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