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121.
Myostatin (MSTN), known as growth and differentiation factor 8 (GDF-8), is a member of the transforming growth factor β (TGF-β) superfamily that negatively regulates skeletal muscle mass. Myostatin binds with high affinity to the receptor serine threonine kinase activin receptor type IIB (ActRIIB). Activins that also belong to the TGF-β superfamily, stimulate follicle-stimulating hormone production in gonadotrophs and suppress growth hormone and adrenocorticotropic hormone production in somatotrophs and corticotrophs, respectively. The aim of the present paper was therefore to clarify the endocrine action of MSTN in adenohypophysis. The present study details the expression and cellular localization of MSTN and ActRIIB in porcine anterior pituitary gland. The mRNA of MSTN and ActRIIB was consistently expressed in RT-PCR. Immunohistochemistry of MSTN and specific hormones showed that MSTN localized in thyrotrophs and gonadotrophs, in which most of the MSTN immunoreactive cells were identified as thyrotrophs. The immunostaining of ActRIIB was restricted to corticotrophs. These results indicate that MSTN was mainly produced in thyrotrophs and its receptor, ActRIIB, was restrictively contained in corticotrophs. Interestingly, thyrotrophs immunoreactive for MSTN were frequently close to corticotrophs immunoreactive for ActRIIB. The present study suggests that MSTN from thyrotrophs may regulate corticotroph function as a paracrine mediator among the porcine anterior pituitary cells.  相似文献   
122.
Expression of 150 kda oxygen-regulated protein, ORP150, was examined in the atheromatous lesions on aortic valves in high-fat diet fed mice. Immunohistochemical staining revealed that ORP150 was expressed on the surface of plaque and was co-localized with phagocytes bearing Mac-3, a mouse macrophage differentiation antigen. These findings suggest that ORP150 is involved in the development of the atheromatous plaque. Titer of autoantibody against ORP150 was gradually elevated in parallel with the length of period of high-fat diet feeding. These results suggest that the deposition of immunocomplex toward ORP150 antigen is involved in atheromatous plaque progression.  相似文献   
123.
Trypsin from tongol tuna (Thunnus tonggol) spleen was purified to 402-fold by ammonium sulfate precipitation, followed by a series of chromatographic separations. The molecular mass of trypsin was estimated to be 24 kDa by size-exclusion chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Trypsin appearing as a single band on native PAGE showed the maximal activity at pH 8.5 and 65 degrees C. It was stable in a wide pH range of 6-11 but unstable at the temperatures greater than 50 degrees C. The enzyme required calcium ion for thermal stability. The activity was strongly inhibited by 1.0 g/L soybean trypsin inhibitor and 5 mM TLCK and partially inhibited by 2 mM ethylenediaminetetraacetic acid. Activity was lowered with an increasing NaCl concentration (0-30%). The enzyme had a Km for Nalpha-p-tosyl-L-arginine methyl ester hydrochloride of 0.25 mM and a Kcat of 200 s-1. The N-terminal amino acid sequence of trypsin was determined as IVGGYECQAHSQPHQVSLNA and was very homologous to other trypsins.  相似文献   
124.
The objective was to evaluate effects of feeding level of milk replacer on body growth, plasma metabolite and insulin concentrations, and allometric growth of visceral organs in suckling calves. Holstein bull calves (n = 8; 3–4 days of age) were fed either a low amount (average 0.63 kgDM/day, LM) or high amount (average 1.15 kgDM/day, HM) of high protein milk replacer until they were slaughtered at 6 weeks of age. Body weight (BW) at 4, 5, and 6 weeks of age, feed intake, average daily gain, and feed efficiency were higher in the HM than LM calves. The HM group had higher plasma glucose at 3 and 4 weeks of age and insulin levels after the age of 4 weeks compared with LM calves whereas no effect was detected on plasma nonesterified fatty acid or urea nitrogen concentrations. The HM calves had greater empty body weight (EBW), viscera‐free BW and most of the organs dissected than LM calves. Relative weights (% of EBW) of liver, spleen, kidneys, and internal fat were higher, whereas head and large intestine was lower in HM than LM calves. The results suggest that increased milk feeding levels would accelerate the growth of the body and specific organs.  相似文献   
125.
The effects of thiopental, ketamine, diazepam, xylazine and nitrous oxide, and combinations of thiopental-nitrous oxide and ketamine-nitrous oxide on electroencephalographic (EEG) spike activity and convulsive behaviors in atropinized cats at surgical depth of enflurane anesthesia were assessed quantitatively for 60 minutes during spontaneous ventilation. Mean inspired enflurane concentrations (MIEC) were reduced 16% to 29% by pretreatment with thiopental, ketamine, diazepam, and xylazine, and were reduced 19% by 66% nitrous oxide. The MIEC of cats anesthetized with thiopental-nitrous oxide-enflurane and ketamine-nitrous oxide-enflurane were 35% to 38% lower than that with nitrous oxide-enflurane. Pretreatment with thiopental, ketamine, diazepam, and xylazine did not reduce the EEG spike frequency during anesthesia but did markedly reduce the spike amplitude. The addition of 66% nitrous oxide did not alter the spike frequency during anesthesia but tended to reduce the spike amplitude. Combinations of thiopental-nitrous oxide and ketamine-nitrous oxide almost abolished the spike activity. The addition of 66% nitrous oxide prevented convulsive responses elicited by photic and auditory stimulation during enflurane anesthesia. Treatment with thiopental, ketamine, diazepam and xylazine, and combinations of thiopental-nitrous oxide and ketamine-nitrous oxide, completely prevented convulsive responses during enflurane anesthesia.  相似文献   
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ABSTRACT: Hydroxy fatty acid isomers derived from phosphatidylcholine hydroperoxides (PC-OOH) in the livers of three fish species, including sweet smelt, yellowtail and rainbow trout, were determined by selected ion monitoring of gas chromatography/mass spectrometry. Total molar amounts of all hydroxy fatty acids determined in the present study coincided well with those of PC-OOH reported previously, suggesting that hydroxy fatty acid composition reflects hydroperoxide composition. The total amount of hydroperoxide isomers accumulated in the livers of sweet smelt was much higher than those of yellowtail and rainbow trout. The amounts of certain isomers, including 10-hydroperoxy octadecanoic acid, 12-hydroperoxy eicosanoic acid and 14-hydroperoxy docosanoic acid, were significantly higher than those of rainbow trout and yellowtail. These results suggest that differences in the contents and compositions of certain hydroperoxide isomers, which are possible precursors of a watermelon-like or cucumber-like aroma, result in differences of fresh fish aroma between aromatic fish and non-aromatic fish.  相似文献   
129.
S100B in cerebrospinal fluid (CSF-S100B) was measured in calves with 20 neurologic and 21 non-neurologic diseases to clarify its utility as a biomarker for neurologic diseases. The median CSF-S100B value in the neurologic disease group (43.0 ng/ml) was significantly higher than that in the non-neurologic disease group (10.2 ng/ml). As CSF-S100B levels in calves with neurologic diseases widely differed, the utility of CSF-S100B as a diagnostic marker for neurologic diseases in cattle remains inconclusive.  相似文献   
130.
Heat processing is responsible for the change in the flavor of a coffee drink. In this study, the application of gas chromatography-olfactometry of headspace samples (GCO-H) using the vapor fraction before and after heat processing of the coffee samples resulted in the detection of 12 odor-active peaks for which the flavor dilution (FD) factors changed. Eight potent odorants were identified from these peaks by gas chromatography-mass spectrometry (GC-MS). Among these components, methanethiol (putrid), acetic acid (sour), 3-methylbutanoic acid (sour), 2-furfuryl methyl disulfide (meaty), and 4-hydroxy-2,5-dimethyl-3(2H)-furanone (caramel-like) increased after heating of the coffee sample, whereas 2-furfurylthiol (roasty), methional (potato-like), and 3-mercapto-3-methylbutyl formate (roasty) decreased compared with the coffee sample before heat treatment. In addition, extensive studies have been carried out on the pH effects on the change in the concentration of 2-furfurylthiol during heat processing and in the pH range of 5-7; it was found that the concentration of this compound in the model solutions had significantly changed.  相似文献   
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