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61.
Histiocytic sarcoma (HS) is a rare neoplasm of macrophages or dendritic cells with a poor prognosis in dogs. As the apoptosis inhibitor of macrophage (AIM) is characteristically expressed in canine macrophages, we hypothesised that AIM is involved in the development or progression of HS in dogs. In this study, AIM expression in the tumour region and serum AIM levels in dogs with HS was assessed. Additionally, the effects of AIM overexpression on HS cell viability were investigated using a HS cell line that was selected from five validated HS cell lines. Immunohistochemistry showed that AIM expression was observed in the cytoplasm of the HS cells. CD36, a candidate AIM receptor, was also observed on the cell membrane of HS cells. When the serum AIM level was detected in 36 dogs with HS and 10 healthy dogs via western blot analysis, the AIM levels in the HS dogs were significantly higher than those in the controls. AIM mRNA expression in the 5 HS cell lines varied but was higher than that in the other tumour-derived lines. Among the five HS cell lines, DH82 originally had lower AIM and the highest CD36 expression. When AIM was overexpressed in DH82, therein cell growth speed and invasion, apoptosis inhibition and phagocytic activity were strongly upregulated. These data suggest that elevated intra-tumour expression of AIM could induce the progression of HS cells in dogs. Moreover, elevated serum AIM levels in dogs with HS could serve as a biomarker of HS.  相似文献   
62.
The anticholinergic effects of 7 benzodiazepines, bromazepam, camazepam, chlordiazepoxide, diazepam, lorazepam, medazepam and triazolam, were compared by examining their inhibitory effects on the acetylcholine receptor-operated potassium current (I(K).(ACh)) in guinea-pig atrial myocytes. All of these benzodiazepines (0.3-300 μM) inhibited carbachol (1 μM)-induced I(K).(ACh) in a concentration-dependent manner. The ascending order of IC(50) values for carbachol-induced I(K).(ACh) was as follows; medazepam, diazepam, camazepam, triazolam, bromazepam, lorazepam and chlordiazepoxide (>300 μM). The compounds, except for bromazepam, also inhibited I(K).(ACh) activated by an intracellular loading of 100 μM guanosine 5'-[γ-thio]triphosphate (GTPγS) in a concentration-dependent manner. The ascending order of IC(50) values for GTPγS-activated I(K).(ACh) was as follows; medazepam, diazepam, camazepam, lorazepam, triazolam chlordiazepoxide (>300 μM) and bromazepam (>300 μM). To clarify the molecular mechanism of the inhibition, IC(50) ratio, the ratio of IC(50) for GTPγS-activated I(K).(ACh) to carbachol-induced I(K).(ACh), was calculated. The IC(50) ratio for camazepam, diazepam, lorazepam, medazepam and triazolam was close to unity, while it for chlordiazepoxide could not be calculated. These compounds would act on the GTP binding protein and/or potassium channel to achieve the anticholinergic effects in atrial myocytes. In contrast, since the IC(50) ratio for bromazepam is presumably much higher than unity judging from the IC(50) values (104.0 ± 30.0 μM for carbachol-induced I(K).(ACh) and >300 μM for GTPγS-activated I(K).(ACh), it would act on the muscarinic receptor. In summary, benzodiazepines had the anticholinergic effects on atrial myocytes through inhibiting I(K).(ACh) by different molecular mechanisms.  相似文献   
63.
Several amino acids have effects on mental function, including sedative, antidepressant‐like and anxiolytic‐like effects. However, the influence of integrated amino acid nutrition as protein constituents on mental function remains unclear. Therefore, the purpose of the present study was to compare the influence of chicken, pork and beef protein extracts on brain monoamine metabolism in mice. Changes in monoamine levels and their turnover rates in the brain were induced by different protein sources. In particular, chicken protein group showed the highest norepinephrine levels in the hippocampus and hypothalamus, and beef protein extract caused an activation of the serotonergic system in the hypothalamus, although there were no significant differences in amino acid compositions of these protein extracts. Therefore, it was revealed that amino acid compositions in dietary protein did not induce alteration in monoamine metabolism. However, there were differences in small molecular peptides, such as creatine, carnosine and anserine levels in animal protein extracts. In conclusion, monoamine metabolism was altered by dietary protein sources. However, it was indicated that the alteration in monoamine metabolism may be independent from amino acid compositions in dietary protein. In addition, alteration in monoamine metabolism depending on the dietary protein sources may be induced by small molecular peptides.  相似文献   
64.
Several studies have shown a relationship between depression and animal protein intake. To evaluate whether the difference of dietary chicken protein levels induces an antidepressant‐like effect and potentiates acute antidepressant effects, three levels of dietary chicken protein were used as the representative animal protein with imipramine used as the antidepressant. In addition, the effects of dietary chicken protein on brain metabolism were evaluated. Open field test (OFT) and forced swimming test (FST) were conducted on the 27th and 28th days, respectively. OFT and FST were not influenced by both imipramine and dietary protein levels. However, characteristic effects of imipramine treatment on brain monoamine metabolism were observed in the cerebral cortex and hypothalamus. In addition, dietary protein significantly increased taurine and L‐ornithine levels even though these amino acids were not contained in the diets. In conclusion, the metabolism of several amino acids in the plasma and brain were altered by dietary chicken protein.  相似文献   
65.
Although our previous report demonstrated that adiponectin and AdipoR1 gene expressions changed among different lactation stages in the bovine mammary gland, its in vivo kinetics remain unclear in ruminant animals. In this study, we investigated the changes in circulating concentrations of adiponectin, as well as other metabolic hormones and metabolites, (i) during the periparturient period and (ii) among different lactation stages, in Holstein dairy cows. In experiment 1, serum adiponectin concentrations increased after parturition. Serum insulin concentrations were lower in the postpartum than prepartum period, whereas serum growth hormone (GH) concentrations increased in the postpartum period. Serum nonesterified fatty acids (NEFA) levels were increased during the postpartum period and were dependent on the parity. In experiment 2, there was no significant difference in plasma adiponectin concentrations among lactational stages. Plasma insulin concentrations tended to be lower in early lactation while plasma GH levels tended to be higher. Plasma NEFA concentrations were significantly lower in mid‐ and late‐lactation stages than non‐lactation stages. These findings indicate that elevation of serum adiponectin might be involved in energy metabolism just around parturition, and might exert its action through regulation of receptor expression levels in target tissues in each lactational stage in Holstein dairy cows.  相似文献   
66.
In this retrospective study, two observers independently reviewed thoracic imaging studies of 39 dogs with confirmed histiocytic sarcoma. The most common findings were intrathoracic lymphadenopathy, identified by the first and second observers in 82.1% and 87.2% of dogs, respectively, and pulmonary masses (74.4% and 82.1%). Right middle lung lobe masses were significantly more common than masses in any other lung lobe (P<0.0013), with the majority having a ventral distribution. Sternal and tracheobronchial lymphadenopathy were significantly more common than cranial mediastinal lymphadenopathy (P‐values of 0.0002 and 0.012, respectively). Interobserver agreement regarding distribution of lymphadenopathy and pulmonary masses was good (κ=0.64 and 0.75, respectively). Other findings included pulmonary nodules, pleural effusion, and abnormal pulmonary patterns. In patients with CT examinations, the majority of masses were mildly to moderately enhancing and heterogeneous, poorly marginated, and bronchocentric. Lymphadenopathy and pulmonary masses are the most common intrathoracic findings in dogs with histiocytic sarcoma, and the strong predilection for the ventral aspect of the right middle lung lube may help to differentiate it from other types of neoplasia.  相似文献   
67.
We provided comfortable resting areas in pens and tools for self-grooming and suppressing aggressive behavior for environmental enrichment in Japanese black and Japanese Shorthorn calves. At the start of the experiment, the black calves ( n  = 10) were 164 days old and 138 kg in weight, and the Japanese Shorthorn calves ( n  = 10) were 176 days old and 164 kg in weight. Calves of each breed were divided into two groups (the enrichment group and the non-treatment group), and each group was housed in a 4 m × 7.2 m pen. The effect of enrichment on calf welfare was estimated on the basis of daily weight gain and behavior. The brush stimulated the grooming behavior in calves although the mean time of using the brush decreased during the experiment. The partition of the feed trough and the wooden wall in the pen decreased the agonistic behavior in Japanese Shorthorn calves ( P  < 0.01) and increased the affiliative behavior in Japanese black calves ( P  = 0.08). The cleanliness of the bedding increased sternum lying and lying with the head touching the flank or ground in Japanese black calves and decreased the standing resting behavior in both breeds ( P  < 0.05 in all the cases). However, the treatments did not have an effect on daily weight gain. We concluded that the treatments would improve the welfare of calves and function as environmental enrichments.  相似文献   
68.
An experiment was conducted to determine the effects of inclusion levels of potato pulp silage in concentrate (0, 15, 30 or 45%; on a dry matter basis) and roughage sources (rice straw or wheat straw) on finishing performance and carcass quality of cull beef cows. Sixteen Japanese Black (Wagyu) mature cull cows (490 ± 31 kg of BW) were used in this experiment. Increasing the levels of potato pulp silage in concentrate and roughage sources did not significantly affect feed intake in cows. In addition, the final body weight, daily gain and feed : gain ratio were not influenced by the inclusion levels of potato pulp silage in concentrate and the type of roughage. Increasing the inclusion levels of potato pulp silage in concentrate would probably decrease the marbling score. The L* values of the longissimus muscle (LM) tended to respond quadratically ( P  = 0.078) as the inclusion levels of potato pulp silage in concentrate increased, and was lowest for cows fed the concentrate which included 30% potato pulp silage. The a* and b* values of the LM and fat color were not affected by the inclusion levels of potato pulp silage in concentrate. No effects of roughage sources on finishing performance were observed.  相似文献   
69.
To clarify colonic fermentation during the perinatal period, 22 dairy calves less than 6 weeks old were used. They were given a milk replacer following colostrum feeding. A total 100 samples of normal feces including meconium were collected from the rectum of the calves. Fecal pH, alcohols, lactate and volatile fatty acids (VFAs) were analyzed. Higher ethanol and n -propanol concentrations were found in many fecal samples particularly in the first 2 weeks after birth, but these metabolites showed consistently lower concentrations thereafter. By contrast, higher concentrations of methanol were observed in some samples for all ages examined. Fecal VFA increased abruptly within a few days of birth, and mainly consisted of acetate and n -butyrate. During the first 2 weeks, the proportion of n -butyrate in VFAs decreased and that of propionate increased gradually. Proportions of VFAs were almost stable at 3–6 weeks of age (acetate, propionate and n -butyrate in increasing order). Higher concentrations of lactate and lower pHs were observed in the fecal samples during the first 2 weeks, and concentrations decreased thereafter. Accelerated colonic production of ethanol and n -propanol was confirmed during the early 2 weeks, in addition to organic acid fermentation as reported previously.  相似文献   
70.
Isoenzyme variation of 198 isolates of Phytophthora infestans collected from many locations in Japan during 1987–90, and of four pre-1987 isolates, was examined using starch gel electrophoresis. A previously unreported allele at malic isoenzyme locus/ME (90) was observed. An association between mating types and isoenzyme genotypes at three isoenzyme loci, glucosephosphate isomerase (GPI-1), peptidase (PEP-1) and ME, was found. At PEP-1, the A2 isolates from Japan had a previously unreported genotype (96/96). Normal segregation at the malic isoenzyme locus occurred in a cross of Japanese and Mexican parents. The results provide evidence of a change in the population genetic structure of P. infestans in Japan.  相似文献   
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