GENERATIVE CYCLES OF PROTEIN AND TRANSAMINASE IN THE GROWING CORN RADICLE

1959 ◽  
Vol 37 (4) ◽  
pp. 621-639 ◽  
Author(s):  
F. S. Cook

Measurements have been made of growth rates, cell numbers, fresh and dry weights, protein and soluble nitrogen levels, and glutamic–aspartic transaminase activity in six successive 2 mm segments of the radicles of 3-day-old corn seedlings. The measured quantities of protein and enzyme activity are related to the stage of average cellular development, to a linear distance scale along the axis of the radicle, and to the time scale. Increments per cell per hour during cell growth are therefore computed. An attempt is made to explain the significance of the genesis of the transaminase in the growth and development of the radicle cells, to the concurrent genesis of total and specific protein, and to other generative cycles.

Author(s):  
Ricardo Ortiz Ortega ◽  
Karla S. Martínez Elizalde ◽  
Tomás Ernesto Villamar-Duque

<p>Teratogenic effect of herbicide glyphosate-Roundup, sold under the name Glifotox on Wistar rats was evaluated. The biological material was treated intraperitoneally with glyphosate at concentrations of 100, 125, and 150 mg/kg from gestation day nine. Hysterectomy was performed on day 18 of gestation, and the uterine horns where the embryos were located, in addition to recording the percentage of malformed embryos by modifying the method of Wilson were observed. The liver was removed and quantified by spectrophotometry with transaminase activity showed higher concentrations malformation rate and higher enzyme activity was 125 mg/kg, below is the average of 100 mg/kg and higher concentrations such as 150 mg/kg a large number of resorptions was obtained. It is concluded that glyphosate is toxic affecting the liver and liver enzymes involved in the formation of amino acids also produce delay in embryonic development.</p>


1985 ◽  
Vol 100 (5) ◽  
pp. 1540-1547 ◽  
Author(s):  
B Lathrop ◽  
E Olson ◽  
L Glaser

The regulation of creatine phosphokinase (CPK) expression by polypeptide growth factors has been examined in the clonal mouse muscle BC3H1 cell line. After arrest of cell growth by exposure to low concentrations of serum, BC3H1 cells accumulate high levels of muscle-specific proteins including CPK. The induction of this enzyme is reversible in the presence of high concentrations of fetal calf serum, which cause quiescent, differentiated cells to reenter the cell cycle. Under these conditions, the rate of CPK synthesis is drastically reduced. We show in the present communication that either pituitary-derived fibroblast growth factor (FGF) or brain-derived FGF are as effective as serum in repressing the synthesis of CPK when added to quiescent, differentiated cells. The decrease in the rate of synthesis of CPK occurs within 22 h after the addition of pituitary FGF to the cells. Pituitary FGF had very little effect, if any, on the rate CPK degradation. The overall rate of protein synthesis and the pattern of synthesis of the major polypeptides made by these cells was not altered by the addition of FGF. Although pituitary FGF was mitogenic for BC3H1 cells, the rate of cell growth was not absolutely correlated with the extent of repression of CPK. Brain-derived FGF fully repressed CPK induction under conditions where it showed no significant mitogenic activity. These results show that the expression of a muscle-specific protein, CPK, can be controlled by a single defined polypeptide growth factor in fully differentiated cultures, and that initiation of cell division is not required for their regulation to take place.


PEDIATRICS ◽  
1959 ◽  
Vol 24 (3) ◽  
pp. 360-361
Author(s):  
SAMUEL P. BESSMAN

THE MEASUREMENT of enzyme activity of serum as an indicator of disease has a long history in medicine. In the past, it has been the aim of the designers of these methods to make them as specific as possible for assay of an enzyme characteristic of a particular system or group of similar organs. Examples of these venerable tests are those for amylase, acid phosphatase, alkaline phosphatase and choline esterase in the serum. Warburg made the first departure from this specificity by demonstrating that the activity of triosephosphate dehydrogenase in the serum of animals with cancer was much greater than that of controls. This test was partially specific, for as Warburg had earlier shown, the glycolytic activity of tumors is much greater than that of normal tissues. The non-specific approach became extreme with the introduction of the measurement of the glutamic-oxalacetic transaminase reaction in the diagnosis of acute coronary disease.


2003 ◽  
Vol 33 (8) ◽  
pp. 2223-2232 ◽  
Author(s):  
Jeffrey C. Rathmell ◽  
Rebecca L. Elstrom ◽  
Ryan M. Cinalli ◽  
Craig B. Thompson

1966 ◽  
Vol 12 (4) ◽  
pp. 217-225 ◽  
Author(s):  
J S Annino

Abstract Study of the colorimetric transaminase method of Reitman and Frankel for the determination of serum glutamic oxalacetic transaminase activity revealed the following: (1) although maximum absorption occurs at 444 mµ, absorbance readings at 505 mµ gave satisfactory results; (2) color development is immediate and the color is stable for at least 1 hr.; (3) a pyruvate calibration standard may be used; (4) sample blanks are not usually necessary; (5) a reagent blank should accompany each group of analyses and should be used as a photometric reference; (6) the relationship between dilution and enzyme activity is linear; and (7) although the relationship between incubation time and activity is not exactly linear, a factor has been determined to permit the use of a 12-min. incubation period with samples showing high enzyme activity.


Blood ◽  
1999 ◽  
Vol 93 (10) ◽  
pp. 3347-3354 ◽  
Author(s):  
Yuka Nagata ◽  
Friedemann Kiefer ◽  
Takeshi Watanabe ◽  
Kazuo Todokoro

Hematopoietic progenitor kinase-1 (HPK1), which is expressed predominantly in hematopoietic cells, was identified as a mammalian Ste20 homologue that, upon transfection, leads to activation of JNK/SAPK in nonhematopoietic cells. The JNK/SAPK pathway is activated by various environmental stresses and proinflammatory and hematopoietic cytokines. Upstream activators of HPK1 currently remain elusive, and its precise role in hematopoiesis has yet to be defined. We therefore examined the possible involvement of HPK1 in erythropoietin (Epo) and environmental stress-induced JNK/SAPK activation in the Epo-dependent FD-EPO cells and Epo-responsive SKT6 cells. We found that Epo, but not environmental stresses, induced rapid and transient activation of HPK1, whereas both induced activation of JNK/SAPK. A screen for HPK1 binding proteins identified the hematopoietic cell-specific protein 1 (HS1) as a potential HPK1 interaction partner. We found HPK1 constitutively associated with HS1 and that HS1 was tyrosine-phosphorylated in response to cellular stresses as well as Epo stimulation. Furthermore, antisense oligonucleotides to HPK1 suppressed Epo-dependent cell growth and Epo-induced erythroid differentiation. We therefore conclude that Epo induces activation of both HPK1 and HS1, whereas cellular stresses activate only HS1, and that the HPK1-JNK/SAPK pathway is involved in Epo-induced growth and differentiation signals.


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