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1.
We investigated the in vitro differentiation of canine bone marrow stromal cells (BMSCs) into voltage- and glutamate-responsive neuron-like cells. BMSCs were obtained from the bone marrow of healthy beagle dogs. Canine BMSCs were incubated with the basal medium for neurons containing recombinant human basic fibroblast growth factor (bFGF; 100 ng/ml). The viability of the bFGF-treated cells was assessed by a trypan blue exclusion assay, and the morphology was monitored. Real-time RT-PCR was performed to evaluate mRNA expression of neuronal, neural stem cell and glial markers. Western blotting and immunocytochemical analysis for the neuronal markers were performed to evaluate the protein expression and localization. The Ca2+ mobilization of the cells was evaluated using the Ca2+ indicator Fluo3 to monitor Ca2+ influx. To investigate the mechanism of bFGF-induced neuronal differentiation, the fibroblast growth factor receptor inhibitor, the phosphoinositide 3-kinase inhibitor or the Akt inhibitor was tested. The bFGF treatment resulted in the maintenance of the viability of canine BMSCs for 10 days, in the expression of neuronal marker mRNAs and proteins and in the manifestation of neuron-like morphology. Furthermore, in the bFGF-treated BMSCs, a high concentration of KCl and L-glutamate induced an increase in intracellular Ca2+ levels. Each inhibitor significantly attenuated the bFGF-induced increase in neuronal marker mRNA expression. These results suggest that bFGF contributes to the differentiation of canine BMSCs into voltage- and glutamate-responsive neuron-like cells and may lead to the development of new cell-based treatments for neuronal diseases.  相似文献   
2.
ABSTRACT: To investigate the effects of disproportionate levels of dietary arginine and lysine on juvenile Japanese flounder Paralichthys olivaceus , growth performance and biochemical parameters were evaluated by feeding five test diets, comprising different levels of arginine and lysine, to triplicate groups of juveniles (initial bodyweight 1.85 g) for 40 days. Crystalline amino acids were supplemented to test diets to correspond to the amino acid pattern found in the whole body protein of the Japanese flounder, except for arginine and lysine. After the feeding trials, plasma arginine, lysine and urea levels, excreted ammonia-N, and liver arginase activity were analysed. Survival, specific growth rate, feed conversion efficiency, and apparent protein retention were adversely affected ( P  <   0.05) by the deficiency in dietary arginine or lysine concentrations. An excess of either lysine or arginine in the diet did not depress growth when the diets contained adequate levels of either arginine or lysine, proving that there is no evidence for an arginine–lysine antagonism. Results for plasma arginine, lysine and urea levels, excreted ammonia, and liver arginase activity also demonstrated that Japanese flounder juveniles are not sensitive to excess dietary levels of lysine and arginine.  相似文献   
3.
In our previous study, seminal plasma effectively suppressed the induction of sperm to capacitation‐like status and acrosome loss during the thawing process. However, because boar seminal plasma is contaminated with various kinds of bacteria and/or viruses, it is necessary to develop a thawing solution without animal‐derived materials. In this study, we focused on the increase of intracellular Ca2+ ([Ca2+]i) in sperm after thawing and the negative effects of sperm qualities. After thawing, the fluorescent intensity of [Ca2+]i indicator, Fluo‐3/AM, and the level of phosphorylated tyrosine residue of protein were increased in the sperm. Next, we investigated whether the addition of Ca2+ chelators (ethylenediaminetetraacetic acid (EDTA) and ethyleneglycoltetraacetic acid (EGTA)) improved post‐thawed sperm motility. When the frozen–thawed sperm were treated with 6 mmol/L EDTA + 6 mmol/L EGTA, sperm motility was significantly increased as compared with control (6 mmol/L EDTA alone) at all incubation periods (P < 0.05). The combinational treatment significantly suppressed the elevation of [Ca2+]i and the tyrosine phosphorylation, which improved the acrosomal status and fertilizing ability in vitro. Furthermore, when the thawing method was applied for artificial insemination, the fertilization rate was significantly higher than control (P < 0.05, 33% vs. 82%). Thus, we conclude that the addition of EDTA + EGTA to thawing solution is a beneficial tool for artificial insemination using frozen–thawed boar sperm.  相似文献   
4.
Six micro‐bound diets were formulated to contain three levels of choline chloride (CC) (0.0, 0.6 and 1.2 g kg−1) and 2 levels of methionine (Met) (0 and 15 g kg−1). Soybean protein isolates (SPI) were used as the main protein source for its limited Met content. A significant (P < 0.05) interaction was determined between CC and Met on the survival (S %), weight gain (WG%), specific growth rate (SGR % day−1), feed efficiency ratio (FER), protein efficiency ratio (PER) and phosphatidylcholine (PC), phoshphatidylethanolamine (PE) and Met contents of the whole body of shrimp. The shrimp group did not receive either supplemental CC or Met showed lower (P < 0.05) values of the above‐mentioned parameters than other shrimp groups fed with 0.6 and 1.2 g kg−1 supplemental CC with or without Met supplementation. The present study showed that supplementation of 1.2 g kg−1 CC in the diets could compensate shrimp post‐larvae with the needed methyl group when received Met‐deficient diets. The study also assumed that the biosynthesis of PC in the shrimp’s body can be achieved by the methylation of PE through the S‐adenosylmethionine (SAM) pathway and/or through the cytosine di‐phosphoryl (CDP) choline pathway directly from dietary choline.  相似文献   
5.
A feeding experiment was conducted to examine the efficacy of a vitamin C (L‐ascorbic acid, AsA) derivative, l ‐ascorbyl‐2‐monophosphate Na/Ca (AMP‐Na/Ca) by comparing to l ‐ascorbyl‐2‐monophosphate‐Mg (AMP‐Mg) in terms of growth, AsA content in tissues, and hematology in yellowtail Seriola quinqueradiata juvenile (1.10 ± 0.01 g). Furthermore, a stress resistance test for the species fed AMP‐Na/Ca was also conducted. In experiment 1, 11 test pellet diets with different levels of AMP‐Na/Ca (0, 12, 43, 88, 440 and 881 mg AsA kg?1diet) and AMP‐Mg (0, 16, 52, 106, 595 and 1164 mg AsA kg?1 diet) were formulated and fed to the yellowtail three times per day for 50 days. In both the vitamin C sources, the survival rates of the fish fed diets without supplemental AsA were lower than 50% at day 20, and more than 50% mortality occurred in fish that fed the diets containing 12 or 16 mg AsA kg?1 after day 30. However, no significant differences were detected in survival and growth among fish that fed the diets containing more than 43 mg AsA kg?1. Liver and brain AsA concentrations generally increased with increasing dietary AsA level in both sources. In experiment 2, test diets were formulated to contain 43, 88, 440 and 881 mg AsA kg?1 using AMP‐Na/Ca, and after 60 days of feeding, yellowtail juveniles were subjected to low salinity and air exposure stress. The fish that received diets with 440 mg AsA kg?1 showed significantly higher tolerance to low salinity stress and higher survival rate in air exposure stress than those of other groups. The present study demonstrated that yellowtail juveniles could utilize AMP‐Na/Ca as an AsA source like AMP‐Mg, and that supplementation of 43–52 mg AsA kg?1 diet was optimum for normal growth. However, this study showed that dietary inclusion of 440 mg AsA kg?1 would be necessary to improve stress resistance of this species.  相似文献   
6.
The content of collagen and the distribution of hepatic stellate cells (HSCs) were studied to elucidate the occurrence of sex‐dependent variations in the liver of developing embryos and growing chickens. Chick embryos from embryonic days (e) 12 to e20 and chicks at 1, 4 and 8 weeks were analyzed. Liver tissue was processed using NaOH maceration and freeze‐dried to obtain the collagen fiber specimens. HSCs were identified by double fluorescent immunohistochemistry for desmin and vimentin. There were no sex‐dependent variations in the percentage of collagen fiber per liver weight and HSC area during embryonic stages. However, the content of collagen fiber increased during embryonic development in both sexes. On the other hand, the area of HSCs significantly increased in growing males but did not show any change in females. Importantly, sex differences were observed in both collagen fiber content and HSC area in the liver at 8 weeks. These results indicate that the occurrence of collagen content variations takes place at 8 weeks in chicken liver, suggesting that a sex‐dependent hormone may play an important role on the collagen production of HSCs in the growing chicken liver.  相似文献   
7.
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8.
The present study was conducted to clarify the effect and the interaction between two choline sources [choline chloride (CC) and soybean phosphatidylcholine (SPC)] on the performances of postlarval shrimp, Marsupenaeus japonicus. A 30‐day feeding experiment was conducted as a 2 × 2 factorial design. The postlarval shrimp were fed with four κ‐carrageenan micro‐bound diets that contained two levels of CC (0.6 and 1.2 g kg−1) and two levels of SPC (20 and 40 g kg−1). A significant (P < 0.05) interaction was also detected between both choline sources in terms of the weight gain, apparent feed efficiency ratio, apparent protein efficiency ratio and total lipid, free choline and phosphatidylcholine contents of the shrimp whole body except for survival, moisture, and protein contents of the whole body. At the lower dietary SPC (20 g kg−1) level, increasing of CC level from 0.6 to 1.2 g kg−1 significantly enhanced the above parameters, whereas such positive effect of dietary CC was diminished at the higher dietary SPC (40 g kg−1) level. Standing on the different viewpoint, the effect of supplemental SPC was also affected with the dietary levels of CC.  相似文献   
9.
A 70‐day feeding experiment was conducted to assess the dietary vitamin A (VA) requirements of juvenile Japanese flounder (Paralichthys olivaceus). Six semi‐purified diets with VA supplementations of 0, 5000, 10 000, 15 000, 20 000 and 25 000 IU kg?1 were fed twice a day to triplicate groups of 20 juveniles per tank with an initial weight of 1.59 ± 0.01 g (mean ± SE). Weight gain (WG) and specific growth rate (SGR) increased as dietary VA increased up to 10 000 IU kg?1. Significantly lower WG and SGR were observed for the 0 IU kg?1 treatment than for treatments of 5000, 10 000 and 15 000 IU kg?1. Highest WG and SGR were observed in fish fed 10 000 IU kg?1; slightly lower values were recorded in fish fed 15 000, 20 000 or 25 000 IU kg1. No significant difference was observed in survival rate among treatments. Whole body total lipid was significantly higher in fish fed 0 and 5000 IU kg?1 than for other levels. Reduced growth and small livers were observed as signs of VA deficiency in fish fed 0 IU kg?1. Slightly reduced growth and pale fragile livers were observed as effects of VA excess in fish fed 25 000 IU kg?1. Total retinol contents in liver and eyes increased with increasing levels of dietary VA. No retinol was detected in livers, and significantly lower total retinol content was observed in eyes, of fish fed 0 IU kg?1. WG analysed by the broken line method indicated that an optimum dietary VA requirement of 9000 IU kg?1.  相似文献   
10.
Pulmonary hypertension (PH) is a common comorbidity in dogs with myxomatous mitral valve disease (MMVD), and can induce various changes in the right heart, such as right ventricular (RV) hypertrophy, dilatation, and dysfunction. We hypothesized that RV function, not only systolic function but also diastolic function, could be worsened with PH progression. We aimed to compare RV systolic and diastolic function in dogs with MMVD. Twenty healthy dogs and sixty-eight dogs with MMVD were enrolled. Dogs with MMVD were classified into the probability of PH. Two-dimensional and Doppler echocardiographic indices for right heart and two-dimensional speckle tracking echocardiography indices were measured. The morphological indicators of the right heart were significantly higher only in the high probability of PH group. The RV strain, early-diastolic and systolic strain rates were significantly lower in the high probability of PH group than those in the low and intermediate probability of PH groups. Multivariate analysis showed that increased RV internal dimension normalized by body weight and RV myocardial performance index were significantly associated with the presence of right-sided congestive heart failure. Speckle tracking echocardiography-derived RV systolic and diastolic function were activated in the low and intermediate probability of PH groups. However, dogs with high probability of PH showed RV myocardial dysfunction and dilatation. Increased RV myocardial performance index and end-diastolic RV internal dimension normalized by body weight were significantly associated with the presence of right-sided congestive heart failure in dogs with MMVD.  相似文献   
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