scholarly journals Histolysis, Histogenesis, and Differentiation during Insect Metamorphosis in Relation to Metabolic Changes

Development ◽  
1953 ◽  
Vol 1 (3) ◽  
pp. 279-282
Author(s):  
Ivar Agrell
Keyword(s):  
Oxygen Consumption ◽  
Metabolic Activity ◽  
Marked Decrease ◽  
Metabolic Changes ◽  
Limiting Factor ◽  
Heme Group ◽  
Enzyme Systems ◽  
Insect Metamorphosis ◽  
Prosthetic Heme Group ◽  
Protein Part

The most obvious change in metabolism during the more advanced type of insect metamorphosis is the change in the integral metabolic activity. After pupation there is first a marked decrease and later an increase of, for instance, the oxygen consumption. The respiratory metabolic curve is U-shaped. The cause of this change is a corresponding variation in the activity of oxidative enzyme systems. If one compares the variation of the spontaneous Mb-reduction and of the oxygen consumption in the fly Calliphora, one finds that the two curves have almost the same course (Agrell, 1947b). This shows an important co-operation of the dehydrogenase systems. The cytochrome system also shows a similar U-shaped variation during the period of metamorphosis, according to Wolsky (1938), Williams (1948) and Sacktor (1950). One limiting factor is the protein part of the enzymes, which is first broken down and later rebuilt (Agrell, 1946). Another limiting factor is the prosthetic heme group in the cytochromes (Williams, 1951).

scholarly journals The significance of soil microorganisms as a limiting factor in infection of clover by Sclerotinia trifoliorum erikss. at different times of the year

1964 ◽  
Vol 36 (1) ◽  
pp. 120-134
Author(s):  
Anna-Marja Halkilahti
Keyword(s):  
Soil Microorganisms ◽  
Soil Microbes ◽  
Marked Decrease ◽  
Petri Dish ◽  
Soil Samples ◽  
Pronounced Effect ◽  
The Other ◽  
Limiting Factor ◽  
Sclerotinia Trifoliorum ◽  
Other Hand

In the petri dish trials the mycelia of Sclerotinia trifoliorum in sterilized soil samples generally infected clover quite readily. In unsterilized samples the infection was less severe and showed marked variations in different years and at different times of the year. In the outdoor trials clover became less infected in the middle of the summer than in the spring and autumn. On the other hand, in the thermostat trials, where the temperature was constantly 7—10°C, the temperature at the time of taking the soil samples did not have a pronounced effect on the extent of clover infection. Liming of the soil caused a marked decrease in the severity of clover rot infection. In some autumns clover plants growing in soil samples taken from fallow were more seriously infected than those growing in soil from a clover field. As a rule, however, there were only slight variations in the extent of infection in the soil samples taken at the same time from the various areas of the field cultivated in different ways. In general, the highest numbers of microorganisms in the soil were found in the autumn and the lowest in the spring. In clover fields there were often more microorganisms – particularly in the autumn – than in fallow. Liming caused an increase in the numbers of soil microbes. S. trifoliorum infected clover very severely at temperatures of 0—5°C; in the range 5—21°C the infection grew generally milder the more the temperature was found to be rising. At temperatures of 5– 10°C an increase in the numbers of soil microbes resulted in a decrease in the infection of the clover. Still higher temperatures, which did not increase the numbers of soil microorganisms, nevertheless enhanced the antagonistic power of the soil.

STUDIES ON THERMOGENESIS IN COLD-ACCLIMATED BIRDS

1963 ◽  
Vol 41 (1) ◽  
pp. 2215-2220 ◽  
Author(s):  
R. R. J. Chaffee ◽  
W. W. Mayhew ◽  
M. Drebin ◽  
Y. Cassuto
Keyword(s):  
Oxygen Consumption ◽  
Cytochrome C ◽  
Liver Enzyme ◽  
Intravenous Injection ◽  
Pyridine Nucleotide ◽  
Small Rodents ◽  
Organ Weights ◽  
Enzyme Systems ◽  
And Control ◽  
Shivering Thermogenesis

Effects on oxygen consumption of continuous intravenous injection of various doses of L-noradrenaline were measured in anesthetized chickens acclimated to 1 °C for 3 months, and in controls. No effects were produced in either and it is concluded that noradrenaline is not a calorigenic mediator in cold-acclimated chickens. Liver succinoxidase and liver microsomal pyridine nucleotide-cytochrome c reductases of cold-acclimated and control sparrows were assayed, and there were no cold-induced differences. Since small cold-acclimated mammals show elevation of these liver enzyme systems, the findings indicate that the chemical basis of non-shivering thermogenesis (if this phenomenon is present at all) may involve different mechanisms in birds and mammals. Organ weights were measured, and it was found that in the sparrow, as in small rodents, the kidney and heart become enlarged in response to cold, perhaps indicating a convergent adaptation in these two diverse homoeotherms. Changes in the thickness and changes in color of the pectoral muscles which were observed in the cold-acclimated sparrows are discussed in relation to their possible roles in shivering thermogenesis.

Metabolic Activity of 3,3'-Diiodothyronine and 3,3'-Diiodo-5-Bromothyronine

1956 ◽  
Vol 186 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Chalmers L. Gemmill
Keyword(s):  
Oxygen Consumption ◽  
Metabolic Activity ◽  
Marked Activity

Following the preparation of (±) 3,3'-diiodothyronine and of (±) 3,3'-diiodo-5-bromothyronine, these compounds were tested for metabolic activity. It was found that 3,3'-diiodothyronine had only slight activity in the antigoiter test and in the oxygen consumption test in thyroidectomized rats. In contrast, (±) 3,3'-diiodo-5-bromothyronine had marked activity as compared with (–) 3,3',5-triiodothyronine. It is apparent from these results that iodine in position 5 is important for the activity of 3,3',5-triiodothyronine and it may be replaced by bromine with retention of metabolic activity.

Dioxygenation of Human Serum Albumin Having a Prosthetic Heme Group in a Tailor-Made Heme Pocket

2004 ◽  
Vol 126 (44) ◽  
pp. 14304-14305 ◽  
Author(s):  
Teruyuki Komatsu ◽  
Naomi Ohmichi ◽  
Patricia A. Zunszain ◽  
Stephen Curry ◽  
Eishun Tsuchida
Keyword(s):  
Human Serum Albumin ◽  
Serum Albumin ◽  
Human Serum ◽  
Heme Group ◽  
Heme Pocket ◽  
Prosthetic Heme Group

Lack of coupling between adrenal cortical metabolic activity and blood flow in anesthetized dogs

1992 ◽  
Vol 262 (1) ◽  
pp. 1-1
Author(s):  
N. T. Sakima ◽  
M. J. Breslow ◽  
H. Raff ◽  
R. J. Traystman
Keyword(s):  
Blood Flow ◽  
Oxygen Consumption ◽  
Adrenal Gland ◽  
Metabolic Activity ◽  
Anesthetized Dogs

Pages H410–H415: N. T. Sakima, M. J. Breslow, H. Raff, and R. J. Traystman. “Lack of coupling between adrenal cortical metabolic activity and blood flow in anesthetized dogs.” Page H412: The units for oxygen consumption in Fig. 3 should read as cc O2/min/100 g adrenal gland.

197 EFFECTS OF HYALURONAN ON OXYGEN CONSUMPTION AND ATP CONTENT IN PIG BLASTOCYSTS PRODUCED IN VITRO

2007 ◽  
Vol 19 (1) ◽  
pp. 215
Author(s):  
K. Yoshioka ◽  
M. Yokoo ◽  
T. Ozawa ◽  
C. Suzuki ◽  
H. Abe ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Metabolic Activity ◽  
Formation Rate ◽  
Defined Medium ◽  
Cell Number ◽  
Total Cell ◽  
Chemically Defined Medium ◽  
Atp Content ◽  
Cell Numbers

Hyaluronan (HA), a glycosaminoglycan present in follicular and oviductal fluids, has been related to sperm capacitation, fertilization, and embryo development. We have found that exogenous HA improves cell proliferation of porcine embryos cultured in a chemically defined medium (Yoshioka et al. 2004 Reprod. Fertil. Dev. 16, 264–265). Moreover, mitochondrial maturation was clearly more advanced in blastocysts cultured with HA compared to those cultured without HA, as seen by transmission electron microscopy. In the present study, the effects of HA on oxygen consumption and ATP content of blastocysts, produced in a defined system which reflects metabolic activity, were investigated. Porcine immature oocytes were matured for 44 h in porcine oocyte medium (POM) and subsequently fertilized with frozen–thawed ejaculated semen in porcine gamete medium supplemented with theophylline, adenosine, and cysteine (PGMtac4). Both POM and PGMtac4 were chemically defined media modified from porcine zygote medium (PZM)-5. After IVF, presumptive zygotes were cultured in PZM-5 containing HA (from the microorganism, Nacalai tesque, Kyoto, Japan) at concentrations of 0 [control], 10 [HA10], or 100 [HA100] �g mL-1 until 5 days after IVF. Blastocyst formation rate and total cell numbers/blastocyst at Day 5 were assessed. In addition, oxygen consumption and ATP content of single Day 5 blastocysts were measured. Blastocyst oxygen consumption was quantified using scanning electrochemical microscopy (HV-403; Research Institute for the Functional Peptides, Yamagata, Japan), and embryonic ATP content was determined using a commercial assay based on the luciferin-luciferase reaction (ATPlite; PerkinElmer, Groningen, The Netherlands). Data were statistically analyzed by ANOVA and Fisher's PLSD test. While the percentage of embryos that developed to the blastocyst stage [30.5% (63/206) to 31.7% (65/206)] did not differ among treatments, blastocyst cell number in the HA100 group [57.9 cells (n = 64)] was greater (P < 0.05) compared to those in the control [48.6 cells (n = 63)] or HA10 [50.0 cells (n = 65)] groups. Blastocyst oxygen consumption rate in the HA100 group [0.629 � 10-14 mol s-1 (n = 15)] was significantly higher than in the control [0.500 � 1-14 mol s-1 (n = 16)] or HA10 [0.464 � 10-14 mol s-1 (n = 14)] groups. ATP content/blastocyst did not differ among treatments [control: 0.645 pmol (n = 38), HA10: 0.727 pmol (n = 42), and HA100: 0.704 pmol (n = 43)]. It is concluded that HA affects the metabolic activity of pig blastocysts developed in a chemically defined medium, enhancing oxygen consumption and their total cell numbers, thus improving the quality of IVP blastocysts.

Malonate and fluoride effects on metabolism and contraction of electrically stimulated heart strips

1961 ◽  
Vol 200 (4) ◽  
pp. 727-731 ◽  
Author(s):  
Leslie I. Rice ◽  
David A. Berman
Keyword(s):  
Oxygen Consumption ◽  
Glucose Metabolism ◽  
Rat Heart ◽  
Contractile Activity ◽  
Simultaneous Recording ◽  
Force Of Contraction ◽  
Enzyme Systems ◽  
Pyruvate Oxidation ◽  
Oxidation Of Glucose ◽  
Stimulation Of

The effect of malonate and fluoride on the oxidation of C14-labeled substrates by electrically stimulated rat heart strips was investigated in an apparatus which permitted simultaneous recording of oxygen consumption and contractile activity. Malonate stimulated the force of contraction when glucose was the substrate, but not in the presence of pyruvate. Malonate had no significant effect on the rate of oxidation of glucose-1-C14, glucose-6-C14 or pyruvate-2-C14, indicating that its effect on contraction was not related to a) stimulation of glucose metabolism, b) inhibition of the Kreb's cycle, or c) stimulation of the phosphogluconate pathway. Malonate-2-C14 was oxidized by the ventricle strips, and the possibility exists that utilization of malonate as a substrate may account, at least in part, for its stimulation of contraction. The stimulation of contraction by fluoride was accompanied by significant alterations in metabolism. The oxidation of glucose and acetate was inhibited, whereas pyruvate oxidation was stimulated; these findings were interpreted in terms of known actions of fluoride on enzyme systems.

scholarly journals On the oxygen consumption rate parts of the chick embryo and fragments of the earthworm

1924 ◽  
Vol 96 (673) ◽  
pp. 146-156 ◽  
Keyword(s):  
Oxygen Consumption ◽  
Chick Embryo ◽  
Metabolic Activity ◽  
Morphological Structure ◽  
Egg Cell ◽  
Tail Region ◽  
Experimental Conditions ◽  
Direct Function ◽  
Physiological Basis ◽  
Living Tissues

In the last few years a considerable number of observations have been made on the respiration rate of regenerating worm fragments, the fertilized egg cell, and growing parts of the embryo. Child (1) as the result of many years’ work in this field has recently put forward an interesting conception of the animal and plant life cycle. In this theory for the first time, an attempt is made to account for development on a straightforward physiological basis. While this hypothesis contradicts many of our current views regarding the significance of the germ cells, reproduction, and inheritance, it certainly brings together under one head more facts than any other theory. Child claims he can demonstrate in all growing organisms certain axial gradients of metabolic activity, which control the appearance of morphological structure. Thus, in Planarian worm fragments the frequency with which the head is regenerated, is a direct function of the axial gradient, which is highest in the head and lowest in the tail region of the worm. To demonstrate the presence of these gradients Child employed weak solutions of KCN, K 2 Mn 2 O 8 and other chemicals. The susceptibility of the living tissues to the action of these agents in a definite manner is taken as evidence of their presence. The question arises do these agents demonstrate gradients of real high and low metabolic activity—or something different? To test this point a large number of determinations have been carried out by Hyman’s (5) on the oxygen consumption of Planarian fragments. The Winkler titration method was used. The results obtained seem to bear out Child’s conclusions based on the direct and indirect susceptibility method in every detail. There are, however, serious objections to the use of the Winkler method of estimating the oxygen consumption of living tissues. In the experiments described in the following paper, I have thought it worth while to reinvestigate the question, using the more direct and accurate manometer method. The following tables give the results of a number of experiments in which the oxygen consumption of head and tail portions of various stages of the chick embryo and the earthworm have been determined in this way. In these measurements rigorous care was taken to avoid sources of error, and every means was adopted of obtaining readings as accurate as possible under the experimental conditions.

MANOMETRIC STUDIES WITH RHIZOSPHERE AND NON-RHIZOSPHERE SOIL

1957 ◽  
Vol 3 (5) ◽  
pp. 673-678 ◽  
Author(s):  
H. Katznelson ◽  
J. W. Rouatt
Keyword(s):  
Amino Acids ◽  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Organic Acids ◽  
Metabolic Activity ◽  
Rhizosphere Soil ◽  
Rhizosphere Soils ◽  
Manometric Studies ◽  
Casamino Acids

Manometric studies were carried out on the metabolic activity of different rhizosphere and non-rhizosphere soils from the greenhouse and the field. Oxygen consumption was distinctly greater with the rhizosphere soils. On the addition of substrates such as casamino acids or a mixture of carbohydrates and organic acids, greater oxygen uptake again occurred with the rhizosphere soils and was particularly striking with the amino acids. Chromatographic studies of extracts of rhizosphere and non-rhizosphere soil incubated with casamino acids suggested that certain amino acids such as arginine, proline, and tyrosine may be preferentially utilized in the rhizosphere.

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