• Asian-Australasian Journal of Animal Sciences
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• v.19 no.2
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• pp.181-188
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• 2006

The objective of this research was to determine the effects of synchronizing the rate of dietary energy and nitrogen release on: ruminal fermentation, microbial protein synthesis, blood urea nitrogen, and nutrient digestibility in beef cattle. Four, two-and-a-half year old Brahman-Thai native crossbred steers were selected for the project. Each steer was fitted with a rumen cannula and proximal duodenal cannula. The steers were then randomly assigned in a $4{\times}4$ Latin square design to receive four dietary treatments. Prior to formulation of the dietary treatments, feed ingredients were analyzed for chemical composition and a nylon bag technique was used to analyze the treatments various ingredients for degradability. The treatments were organized in four levels of a synchrony index (0.39, 0.50, 0.62 and 0.74). The results showed that dry matter digestibility trend to be increased (p<0.06), organic matter and acid detergent fiber digestibility increased linearly (p<0.05), while crude protein and neutral detergent fiber digestibility were not significantly different (p>0.05). Higher concentration and fluctuation of ruminal ammonia and blood urea were observed in the animal that received the lower synchrony index diets. As the levels of the synchrony index increased, the concentrations of ruminal ammonia nitrogen and blood urea nitrogen, at the 4 h post feeding, decreased linearly (p<0.05). Total volatile fatty acid and bacteria populations at the 4 h post feeding increased linearly (p<0.05). Microbial protein synthesis trend to be increase (p<0.08). The results of this research indicate that synchronizing the rate of degradation of dietary energy and nitrogen release improves ruminal fermentation, microbial protein synthesis and feed utilization.

• Journal of Nutrition and Health
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• v.21 no.4
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• pp.242-252
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• 1988

In vivo effects of leucine on skeletal muscle protein synthesis in fed and I-day food deprived young rats were examined. Animals assigned to leucine group were given a single i.p. injection of 80 or 160flmoles of leucine while control group animals were saline sham injected. The rate of protein synthesis was measured by the amount of $^{14}\textrm{C} incorporated into muscle protein after a single injection of $^{14}\textrm{C}-tyrosine, IO$\mu$ Ci/l00g B.W. Examined muscles were two different types of hind limb muscles. the oxidative solues and the glycolytic EDL and plantaris. Administered leucine elevated the concentration of free leucine in soleus muscles by 4-6.8 times the normal level. A massive dose of leucine, 160 flmoles, stimulated protein synthesis in the EDL and plantaris by 24 %, 29 % respectively of straved rats. The soleus of I-day food deprived rats and both types of muscles in fed rats did not respond to the injected leucine. The synthesis rate of the EDL and plantaris was supressed to one-half of the normal while the soleus that was not stimulated by leucine maintained a relatively normal rate, 78 %, of protein synthesis after I-day of food deprivation. Thus, in vivo stimulatory effect of leucine appears to be not a general phenomenon but to be related to the degree of catabolic condition developed by stress such as food deprivation. Although anabolic effects of leucine observed in this study was limited, any applicability of this special property of leucine to human subjects for the purpose of protein sparing in skeletal muscles remains to be examined.

• Journal of Sericultural and Entomological Science
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• v.37 no.1
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• pp.68-73
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• 1995

The toxic effect of Bacillus thuringiensis var, kurstaki $\delta$-endotoxin was determined in the midgut, fat body and Malpighian lobules from larvae of Hyphantria cunea using the au-toradiography and Western blot methods. Bt $\delta$-endotoxin crystals inhibited protein synthesis and elongation factor-2 activity of all tissues tested.

• BMB Reports
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• v.30 no.1
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• pp.55-59
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• 1997

The heat shock response is a universal stress response observed in all organisms and cultured cells. The response is regulated at both the transcriptional and translational level. Heat shocked Drosophila melanogaster Kc cells are used as the system for the study of translational regulation. In this system non-heat shock messages are associated with polysome but are not translated in a heat shocked condition. To figure out the change in the translation machinery. the effects of translation elongation inhibitors were tested on Kc cells. The result showed that the sensitivity of translation to these drugs changed in heat shocked cells. The significant changes were the decreased inhibition of heat shock protein synthesis by cycloheximide, emetine. and puromycin. and the increased inhibition of heat shock protein synthesis by verrucarin A. implying that the translation elongation mechanism in heat shocked cells changed.

• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.344-347
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• 2003

Unnatural amino acid S-(2-nitrobenzyl)cysteine was incorporated into human erythropoietin by using a programmed suppression of nonsense codon in a cell-free protein synthesis system. Several controlling factors affecting the operational efficiency of the suppression were investigated and optimized. The amount of suppressor tRNA and the concentration of $Mg^2+$ were crucial not only for the efficiency but also for the control of the exact suppression. In addition, some general optimization factor are reported in order to improve the efficiency in an unnatural amino acid mutagenesis.

• Korean Journal of Microbiology
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• v.16 no.4
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• pp.148-154
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• 1978

Saccharomyces cerevisiae J170, a mutant, was used for $DL-^{14}C-leucine$ uptake during the sporulation and vegetative stage. $^{14}C-Leucine$ uptake into yeast cells appeared the highest at pH 6.0, indicating the same result of glucose transport, $^{14}C-Leucine$ uptake in sporulation period was higher than in growth phase, showing the evidence that leucine is more required for protein synthesis. This tendency has the evidence tht leucine is more required for protein synthesis. This tendency has the evidence that leucine is more required for protein synthesis. This tendency has been also supported from the result of Km values of leucine uptake in two stages of yeast. Leucine uptake was inhibited by 2,4-dinitrophenol in two stages of yeast. This means that leucine transport system is associated with energy dependent in both stages. The contents of all amino acid in growth phase cells were higher than those of sporulation stge cells, and those of methionine and tyrosine were showed in trace during the sporulation stage. In contrast, the content of glutamic acid in sporulation stage was compared with those of other amino acids.

• The Journal of the Korean Society for Microbiology
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• v.3 no.1
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• pp.51-65
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• 1968

The site of the synthesis of Japanese encephalitis virus(JEV) in the actinomycin-treated and infecter PS Y15 cells(a porcine kidney stable cell line) was observed by the immunofluorescent antibody technique, acridine orange staining, and the autoradiographic analysis. In the parallel studies by immunofluorescent technique and acridine orange staining it the infected cells, Viral protein(as an antigen) and viral RNA were detected at the same site of cytoplasm. In the autoradiographic analysis, the cytoplasmic labeling of $^3H$-uridine was due to the synthesis of JEV-RNA, while the nucleolus and nucleus were not involved. In the autoradiographic studies on the secton of infected cells, the $^3H$-uridine was frequently incorporated around the cytoplasmic vacuoles. This localization of labeling agreed with the site of acridine orange positive granules. The results suggest that the syntheses of the viral RNA and viral protein occurred in the similar site of cytoplasm of the infected cells, and also the virus particles seem to be assembled in the sites of the viral RNA and protein syntheses.

• Nutrition Research and Practice
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• v.3 no.1
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• pp.64-71
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• 2009

Amino acids are fundamental nutrients for protein synthesis and cell growth (increase in cell size). Recently, many compelling evidences have shown that the level of amino acids is sensed by extra- or intra-cellular amino acids sensor(s) and regulates protein synthesis/degradation. Mammalian target of rapamycin complex 1 (mTORC1) is placed in a central position in cell growth regulation and dysregulation of mTOR signaling pathway has been implicated in many serious human diseases including cancer, diabetes, and tissue hypertrophy. Although amino acids are the most potent activator of mTORC1, how amino acids activate mTOR signaling pathway is still largely unknown. This is partly because of the diversity of amino acids themselves including structure and metabolism. In this review, current proposed amino acid sensing mechanisms to regulate mTORC1 and the evidences pro/against the proposed models are discussed.

• International Journal of Industrial Entomology and Biomaterials
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• v.1 no.1
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• pp.1-7
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• 2000

Early studies of the molecular biology of Bacillus thuringeinsis suggested that genetic manipulation of this species could create combinations of genes more useful than those known to occur in natural isolates. Breakthroughs that made these manipulations possible include the cloning of many genes encoding endotoxins, the development of transformation vectors, and various PCR techniques. This paper reviews several genetic factors such as promoters, a 5'mRNA stabilizing sequence, 3'transcription termination sequences, and helper proteins that have been used to enhance crystal protein synthesis, and shows how these genetic elements can be manipulated with new molecular tools to develop more efficacious strains of B. thuringiensis.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.1
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• pp.65-72
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• 2011

Twenty-four Holstein dairy cows were used to evaluate the single and combined effects of different levels of crude protein (CP) and monensin treatment during early lactation on blood metabolites, milk yield and digestion of dairy cows. The experiment was designed as a completely randomized block with a $3{\times}2$ factorial arrangement of treatments. The factors were three concentrations of CP supplement (19.5, 21.4, and 23.4% of dry matter) and two levels of monensin (0 and 350 mg per cow per day). The experiment consisted of three phases and each phase was 3 wk in length. Monensin did not affect milk yield, lactose, solids-non-fat (SNF), blood glucose, triglyceride and DMI, but increased blood cholesterol, blood urea nitrogen (BUN), insulin and reduced blood ${\beta}$-hydroxybutyrate (BHBA), milk fat and protein percentage. Monensin premix significantly decreased rumen ammonia, but rumen pH and microbial protein synthesis were not affected by monensin treatment. Increasing dietary CP improved milk and protein production, but did not alter the other components of milk. Digestibility of NDF, ADF, CP were improved by increasing dietary CP. Increasing dietary CP from 19.5 to 21.4% had no significant effect on ruminal ammonia, but increasing CP to 23.4% significantly increased ruminal ammonia. There was a linear relationship between level of crude protein in the diet and volume of urine excretion. Microbial protein synthesis was affected by increasing CP level; in this way maximum protein synthesis was achieved at 23.4% CP.