Changes in Seryl-tRNA Formative in Developing Chick Muscle

1974 ◽  
Vol 52 (10) ◽  
pp. 838-844 ◽  
Author(s):  
Mark Nwagwu ◽  
John Lianga
Keyword(s):  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Deae Cellulose ◽  
The Other ◽  
Embryonic Chick ◽  
Qualitative And Quantitative ◽  
Embryonic Muscle ◽  
Quantitative Changes ◽  
The One

As a prelude to an analysis of the dependence of muscle protein synthesis on aminoacyl tRNA's, we have investigated the rates of seryl-tRNA formation, in vitro, by aminoacylating systems isolated from 11-, 14-, and 17-day chick embryonic muscle. The results show that the combination of 14-day tRNA and 14-day aminoacyl synthetase is the most efficient in seryl-tRNA formation. We have also studied the qualitative and quantitative changes in seryl-tRNA prepared from 11-, 14-, and 17-day embryonic chick muscle by chromatography of seryl-tRNA on benzoylated DEAE-cellulose columns. The results show that, although there are no qualitative differences in the chromatographic patterns of seryl-tRNA from the different ages, there are significant quantitative differences between the patterns for 11-day and 17-day seryl-tRNA on the one hand, and the pattern for 14-day seryl-tRNA on the other.

scholarly journals EVALUATION OF KNOWLEDGE OF STUDENTS ON GEOGRAPHY: PRINCIPLES, FORMS, A TECHNIQUE

2007 ◽  
Vol 4 (1) ◽  
pp. 34-39
Author(s):  
Laima Railienė
Keyword(s):  
School Reform ◽  
Positive Result ◽  
Key Words ◽  
Positive Emotions ◽  
School Administration ◽  
Assessment System ◽  
The Other ◽  
Knowledge Assessment ◽  
Qualitative And Quantitative ◽  
The One

According to scientists, assessment is tightly connecting teachers, students, parents, school administration. Teacher’s (assessor’s) role is becoming especially important because school reform has changed attitude towards assessment and has created favourable conditions for new ways of assessment. Assessment can show student’s achievement qualitative and quantitative value. Students’ knowledge assessment shows what is known well or weak. Knowledge testing and assessing have a positive result when it is being checked systematically. But it is not good to assess only acquired knowledge. It is very important to make knowledge system, to deepen, to activate students. It is also important to find out how students use theory in practice. If you want to assess correctly, you need to know the forms and kinds of assessment. It is very important not to forget that students must know what they are to remember, because it is impossible to memorize everything. All students want to get good marks. There are several reasons why students react sensitively. From marks parents judge about their child’s abilities and even future profession. On the one hand knowledge assessment gives positive emotions, on the other hand, it gives negative ones. Thus, teachers have to be very careful while checking and assessing. Students themselves need to be assessed, because they can’t know if they study well. Geography teacher has got very wide possibilities to check students’ knowledge and skill. But the most important thing is that students’ knowledge become deeper and stronger if they are checked up systematically and interestingly. Key words: knowledge assessment, assessment system, kinds of assessment, forms of assessment, assessment principles and criteria

Effects of food deprivation on protein synthesis and degradation in rat skeletal muscles

1976 ◽  
Vol 231 (2) ◽  
pp. 441-448 ◽  
Author(s):  
JB Li ◽  
AL Goldberg
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
Food Deprivation ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Rna Content ◽  
Fasted Rats ◽  
Synthesis And Degradation

The effects of food deprivation on protein turnover in rat soleus and extensor digitorum longus (EDL) were investigated. Muscles were removed from fed or fasted growing rats, and protein synthesis and breakdown were measured during incubation in vitro. Rates of synthesis and degradation were higher in the dark soleus than in the pale EDL. One day after food removal protein synthesis and RNA content in the EDL decreased. On the 2nd day of fasting, rates of protein catabolism in this muscle increased. Little or no change in synthesis and degradation occurred in the soleus. Consequently, during fasting the soleus lost much less weight than the EDL and other rat muscles. In unsupplemented buffer or in medium containing amino acids, glucose, and insulin, the muscles of fasted rats showed a lower rate of protein synthesis expressed per milligram of tissue but not per microgram of RNA. Thus the decrease in muscle RNA on fasting was responsible for the reduced synthesis observed under controlled in vitro conditions. In vivo the reduction in muscle protein synthesis on fasting results both from a lower RNA content and lower rate of synthesis per microgram of RNA. Reduced supply of glucose, insulin, and amino acids may account for the lower rate of synthesis per microgram of RNA demonstrable in vivo.

scholarly journals Comparison of protein synthesis and degradation in incubated and perfused muscle

1983 ◽  
Vol 212 (3) ◽  
pp. 649-653 ◽  
Author(s):  
A S Clark ◽  
W E Mitch
Keyword(s):  
Protein Synthesis ◽  
Protein Degradation ◽  
Insulin Treatment ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Muscle Protein Degradation ◽  
Protein Synthesis And Degradation ◽  
Synthesis And Degradation

Rates of muscle protein synthesis and degradation measured in the perfused hindquarter were compared with those in incubated epitrochlearis muscles. With fed or starved mature rats, results without insulin treatment were identical. With insulin treatment, protein synthesis in perfused hindquarters was greater, though protein degradation was the same. Thus rates of muscle protein degradation estimated by these two methods in vitro correspond closely.

scholarly journals Citrulline directly modulates muscle protein synthesis via the PI3K/MAPK/4E-BP1 pathway in a malnourished state: evidence from in vivo, ex vivo, and in vitro studies

2017 ◽  
Vol 312 (1) ◽  
pp. E27-E36 ◽  
Author(s):  
Servane Le Plénier ◽  
Arthur Goron ◽  
Athanassia Sotiropoulos ◽  
Eliane Archambault ◽  
Chantal Guihenneuc ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Ex Vivo ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Fold Increase ◽  
Underlying Mechanism ◽  
Muscle Homeostasis

Citrulline (CIT) is an endogenous amino acid produced by the intestine. Recent literature has consistently shown CIT to be an activator of muscle protein synthesis (MPS). However, the underlying mechanism is still unknown. Our working hypothesis was that CIT might regulate muscle homeostasis directly through the mTORC1/PI3K/MAPK pathways. Because CIT undergoes both interorgan and intraorgan trafficking and metabolism, we combined three approaches: in vivo, ex vivo, and in vitro. Using a model of malnourished aged rats, CIT supplementation activated the phosphorylation of S6K1 and 4E-BP1 in muscle. Interestingly, the increase in S6K1 phosphorylation was positively correlated ( P < 0.05) with plasma CIT concentration. In a model of isolated incubated skeletal muscle from malnourished rats, CIT enhanced MPS (from 30 to 80% CIT vs. Ctrl, P < 0.05), and the CIT effect was abolished in the presence of wortmannin, rapamycin, and PD-98059. In vitro, on myotubes in culture, CIT led to a 2.5-fold increase in S6K1 phosphorylation and a 1.5-fold increase in 4E-BP1 phosphorylation. Both rapamycin and PD-98059 inhibited the CIT effect on S6K1, whereas only LY-294002 inhibited the CIT effect on both S6K1 and 4E-BP1. These findings show that CIT is a signaling agent for muscle homeostasis, suggesting a new role of the intestine in muscle mass control.

Qualitative and quantitative changes in polyphenol composition and bioactivity of Ribes magellanicum and R. punctatum after in vitro gastrointestinal digestion

2017 ◽  
Vol 237 ◽  
pp. 1073-1082 ◽  
Author(s):  
Alberto Burgos-Edwards ◽  
Felipe Jiménez-Aspee ◽  
Samanta Thomas-Valdés ◽  
Guillermo Schmeda-Hirschmann ◽  
Cristina Theoduloz
Keyword(s):  
Gastrointestinal Digestion ◽  
Qualitative And Quantitative ◽  
In Vitro Gastrointestinal Digestion ◽  
Quantitative Changes

Platelet Models and Their Possible Usefulness in the Study of Migraine Pathogenesis

Cephalalgia ◽  
1995 ◽  
Vol 15 (4) ◽  
pp. 265-271 ◽  
Author(s):  
G D'Andrea ◽  
AR Cananzi ◽  
F Perini ◽  
L Hasselmark
Keyword(s):  
Primary Headache ◽  
The Other ◽  
Clinical Aspects ◽  
Metabolic Characteristics ◽  
Dense Bodies ◽  
Migraine Pathogenesis ◽  
Serotonin Turnover ◽  
The One

Platelets may be linked to migraine. On the one hand they are activated during the migraine attack and thus may participate in the pathogenesis of the disorder (the nature of this activation is still unknown). In order to understand this platelet anomaly, we discuss the data available in the literature. In particular, we review recent in vitro studies of a-granules and dense bodies secretion, and aggregation induced by collagen and PAF. On the other hand, platelets share many metabolic characteristics with serotonergic neurons and endothelial cells. Accordingly, platelets have been used to investigate the possible role of serotonin turnover and nitric oxide function in migraine. In both cases, the data obtained have shown peculiar abnormalities that may explain pathogenetic and clinical aspects of primary headache.

Origin of aneuploid plants obtained by anther culture in triticale

1986 ◽  
Vol 28 (3) ◽  
pp. 444-452 ◽  
Author(s):  
Gilles Charmet ◽  
Sylvie Bernard ◽  
Michel Bernard
Keyword(s):  
Chromosome Number ◽  
Anther Culture ◽  
Chromosome Rearrangement ◽  
The Other ◽  
Chromosome Variation ◽  
In Vitro Technique ◽  
Meiotic Irregularities ◽  
Number Frequency ◽  
The One

A very large proportion of plants regenerated from anther culture of triticale F1 hybrids do not show the euploid number of chromosomes. Of 408 androgenetic plants checked for their chromosome numbers, 228 were aneuploid, of which 39 had one or several telosomes. Two observations suggest that most of the chromosome variations observed probably preexist in microspores of the F1 hybrids and would be caused by meiotic irregularities: on the one hand, the majority of these phenomena involve R-genome chromosomes, which also give rise to meiotic univalents; on the other hand, the chromosome number frequency distribution of the microspores from a fairly asyndetic hybrid fits well with that of the androgenetic plants. Thus aneuploidy and chromosome rearrangement do not implicate the in vitro technique itself but rather the choice of the material in triticale.Key words: × triticosecale, in vitro culture, chromosome variation, aneuploidy, C-banding.

Theory and Practice of Functioning Machines for Vibratory Agitation

2015 ◽  
Vol 725-726 ◽  
pp. 590-595
Author(s):  
Viktor Kuzmichev ◽  
Anatoly Lyalinov
Keyword(s):  
Similarity Theory ◽  
Heterogeneous Systems ◽  
Theory And Practice ◽  
The Other ◽  
Interaction Forces ◽  
Qualitative And Quantitative ◽  
Vibration Effect ◽  
The One ◽  
Working Parameters ◽  
Industrial Samples

The article tackles a mechanism of vibration effect on the construction mixes in two representations: corpuscular and phenomenological. It is known that the construction mixes belong to heterogeneous systems, where processes take place in case of vibration effect that are characterized by tixotropy property, i.е. inversability of interaction forces between the particles in case of imposition and removal of mechanical effects. It has been stated that it is more reasonable to find the qualitative and quantitative relations of various processes (phenomena) in the form of generalized relationships obtained by the methods of similarity theory and dimensions of quantity. Presented are the criterial dependencies of changing efficient viscosity of mixes under effect of vibration from the process working parameters. Proposed are the modified Reynolds and Froude criteria for the mixes vibrating processes. It is reasonable to use the method of object internal vibratory protection when designing the vibratory agitation equipment helping reduce the level of vibration influence on the environment on the one hand, and use the vibratory effects on the material being processed to a maximum extent, on the other hand. In order to implement this method it is proposed to use the equalized eccentric vibration exciters. A number of industrial samples of vibration mixers have been presented.

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