THE EFFECT OF LOCAL TEMPERATURE ON THE REACTIVITY TO NORADRENALINE OF DIGITAL VESSELS

1967 ◽  
Vol 45 (1) ◽  
pp. 93-102 ◽  
Author(s):  
Peter Gaskell ◽  
David L. Hoeppner
Keyword(s):  
Intravenous Infusion ◽  
The Other ◽  
Local Temperature ◽  
Continuous Intravenous Infusion ◽  
Opening Pressure ◽  
Simultaneous Measurements ◽  
Critical Opening ◽  
Short Period ◽  
The Mean

The effect of local temperature on the in vivo reactivity of vascular smooth muscle was studied. Reactivity was measured as the increase in critical opening pressure (COP) of digital vessels caused by intravenous infusion of 5 μg of noradrenaline per minute. With one hand cool (22 °C) and the other warm (34 °C) in test experiments or both hands either cool or warm in control experiments, simultaneous measurements were made of the increase in COP of vessels in both middle fingers in response to the noradrenaline. In control experiments the mean increase in COP was similar in right and left fingers, but in test experiments the mean increase was greater in the warm finger than in the cool one. Warm vessels were more reactive to noradrenaline than cool ones (p < 0.01). Because a short period of ischemia is involved in the measurement of COP, other experiments were performed in which the effect of duration of ischemia on the COP, with and without a continuous intravenous infusion of noradrenaline, was ascertained. They suggested that the estimated COP would, in most cases, be about 3 mm Hg less than the COP existing just before the measurement. These results also indicated that although the rate of fall of COP during ischemia was slightly greater for a higher initial COP, the ischemia involved did not invalidate the comparison of the increases in COP caused by noradrenaline in warm and cool fingers, as an index of relative arteriolar reactivity in the test reactivity experiments.

scholarly journals THE EFFECT OF TEMPERATURE UPON FACET NUMBER IN THE BAR-EYED MUTANT OF DROSOPHILA

1920 ◽  
Vol 2 (5) ◽  
pp. 445-464 ◽  
Author(s):  
Joseph Krafka
Keyword(s):  
Immature Stage ◽  
The Other ◽  
Effect Of Temperature ◽  
Wild Stock ◽  
Line Feature ◽  
Exponential Curve ◽  
Straight Line ◽  
Short Period ◽  
The Mean ◽  
Facet Number

Three strains of the bar-eyed mutant of Drosophila melanogaster Meig have been reared at constant temperatures over a range of 15–31°C. The mean facet number in the bar-eyed mutant varies inversely with the temperature at which the larvæ develop. The temperature coefficient (Q10) is of the same order as that for chemical reactions. The facet-temperature relations may be plotted as an exponential curve for temperatures from 15–31°. The rate of development of the immature stages gives a straight line temperature curve between 15 and 29°. Beyond 29° the rate decreases again with a further rise in temperature. The facet curve may be readily superimposed on the development curve between 15 and 27°. The straight line feature of the development curve is probably due to the flattening out of an exponential curve by secondary factors. Since both the straight line and the exponential curve appear simultaneously in the same living material, it is impractical to locate the secondary factors in enzyme destruction, differences in viscosity, or in the physical state of colloids. Differential temperature coefficients for the various separate processes involved in development furnish the best basis for an explanation of the straight line feature of the curve representing the effect of temperature on the rate of physiological processes. Facet number in the full-eyed wild stock is not affected by temperature to a marked degree. The mean facet number for fifteen full-eyed females raised at 27° is 859.06. The mean facet number for the Low Selected Bar females at 27° is 55.13; for the Ultra-bar females at 27° it is 21.27. A consistent sexual difference appears in all the bar stocks, the females having fewer facets. This relation may be expressed by the sex coefficient, the average value of which is 0.791. The average observed difference in mean facet number for a difference of 1°C. in the environment in which the flies developed is 3.09 for the Ultra-bar stock and 14.01 for the Low Selected stock. The average proportional differences in the mean for a difference of 1°C. are 9.22 per cent for Ultra-bar, and 14.51 for Low Selected. The differences in the number of facets per °C. are greatest at the low and least at the high temperatures. The difference in the number of facets per °C. varies with the mean. The proportional differences in the mean per °C. are greatest at the lower (15–17.5°) and higher (29–31°) temperatures and least at the intermediate temperatures. Temperature is a factor in determining facet number only during a relatively short period in larval development. This effective period, at 27°, comes between the end of the 3rd and the end of the 4th day. At 15°, this period is initiated at the end of 8 days following a 1st day at 27°. At 27° this period is approximately 18 hours long. At 15° it is approximately 72 hours long. The number of facets and the length of the immature stage (egg-larval-pupal) appear related when the whole of development is passed at one temperature. That the number of facets is not dependent upon the length of the immature stage is shown by experiments in which only a part of development was passed at one temperature and the remainder at another. Temperature affects the reaction determining the number of facets in approximately the same way that it affects the other developmental reactions, hence the apparent correlation between facet number and the length of the immature stage. Variability as expressed by the coefficient of variability has a tendency to increase with temperature. Standard deviation, on the other hand, appears to decrease with rise in temperature. Neither inheritance nor induction effects are exhibited by this material. This study shows that environment may markedly affect the somatic expression of one Mendelian factor (bar eye), while it has no visible influence on another (white eye).

scholarly journals Hepatoprotective and antineoplastic potencial of red propolis produced by the bees Apis mellifera in the semiarid of Rio Grande do Norte, Brazil

2019 ◽  
Vol 39 (9) ◽  
pp. 744-756
Author(s):  
Jardel B. Silva ◽  
Kaliane A.R. Paiva ◽  
Kizzy M.F.M. Costa ◽  
Geysa A. Viana ◽  
Hélio N. Araújo Júnior ◽  
...  
Keyword(s):  
Ethanolic Extract ◽  
The Other ◽  
Hepatoprotective Effect ◽  
Normal Cells ◽  
Propolis Extract ◽  
Regenerative Nodules ◽  
Serum Biochemical ◽  
The Mean

ABSTRACT: The objective of this study was to evaluate the hepatoprotective effect of the honey bee Apis mellifera ethanolic extract of the red propolis, obtained in four municipalities of the Rio Grande do Norte semi-arid region, through an in vitro evaluation of the antineoplastic potential in human hepatic carcinoma (HepG2) and normal cell lines (L929), and from the comet assay in hepatic cell lines (ZF-L hepatocytes) to evaluate the genoprotective potential of the extract. The hepatoprotective effect was also evaluated in vivo by the induction of chronic experimental hepatic lesions in rodents (Rattus norvegicus Berkenhout, 1769), Wistar line, by intraperitoneal administration of thioacetamide (TAA) at the dose of 0.2g/kg. The animals were distributed in the following experimental groups: G1 (control), G2 (treated with 500mg/kg ethanolic extract of propolis), G3 (treated with 500mg/kg of ethanolic extract and TAA) and G4 (treated with TAA). All rats were submitted to serum biochemical, macroscopic, histological and stereological biochemical exams of the liver. It was verified the genoprotective effect of red propolis since the mean damages promoted to DNA in cells tested with the extract were significantly lower than the mean of the positive control damage (hydrogen peroxide). The red propolis extract did not present cytotoxic activity to the tumor cells of human liver cancer, as well as to normal ones. The absence of cytotoxicity in normal cells may indicate safety in the use of the propolis extract. The results of the serum biochemical evaluation showed that the serum levels of the aminotransferase enzymes (AST) did not differ significantly between G1, G2 and G3 when compared to each other. G4 showed significant increase in levels compared to the other groups, indicating that the administration of the extract did not cause liver toxicity, as well as exerted hepatoprotective effect against the hepatic damage induced by TAA. The G3 and G4 animals developed cirrhosis, but in G3 the livers were characterized by the presence of small regenerative nodules and level with the surface of the organ, whereas in G4 the livers showed large regenerative nodules. The livers of the G1 and G2 animals presented normal histological appearance, whereas the livers of the G3 animals showed regenerative nodules surrounded by thin septa of connective tissue, and in G4 the regenerative nodules were surrounded by thick septa fibrous connective tissue. The analysis of the hepatic tissues by means of stereology showed that there was no statistical difference between the percentage of hepatocytes, sinusoids, and collagens in G1 and G2. In G3 the percentage of hepatocytes, sinusoids, and collagen did not differ significantly from the other groups. It was concluded that the ethanolic extract of the red propolis exerted a hepatoprotective effect, because it promoted in vitro reduction of the damage to the DNA of liver cells, antineoplastic activity in human hepatocellular carcinoma cell line (HepG2) and did not exert cytotoxic effect in normal cells or was able to reduce liver enzyme activity and the severity of cirrhosis induced by TAA in vivo.

scholarly journals Role of transferrin in determining internal iron distribution

Blood ◽  
1977 ◽  
Vol 49 (6) ◽  
pp. 957-966
Author(s):  
P Pootrakul ◽  
A Christensen ◽  
B Josephson ◽  
CA Finch
Keyword(s):  
Isotope Ratio ◽  
Hepatic Uptake ◽  
The Other ◽  
Iron Salts ◽  
Iron Deficient ◽  
Loading And Unloading ◽  
The Mean

The behavior in vivo of transferrin in loading and unloading iron from its two sites was examined in rats. Radioiron entering the plasma from the gastrointestinal tract in iron-deficient, normal and iron-loaded rats did not differ in its subsequent tissue distribution between erythroid marrow and liver of normal recipients from a second isotope added to the same plasma in vitro. Loading studies in vitro were then carried out employing a reticulocyte incubation model designed to place one isotope predominantly on one site of transferrin, more available to the erythron, and the second isotope on the other site, more available to the liver. In 15 groups of animals in which 3 different iron salts were employed to load transferrin with iron, the mean isotope ratio in the erythron was 1.03 (+/-0.06 SD) and the mean liver ratio was 0.75 (+/-0.21 SD). It was found that the incubation of plasma with reticulocytes resulted in contamination of the plasma by radioactive hemoglobin. After allowance was made for hepatic uptake of radiohemoglobin in the 13 groups in which proper correction could be made, the isotope ratio in the liver became 0.97 (+/-0.17 SD). It is concluded that iron atoms from the two sites of transferrin have similar tissue distributions in vivo in the experimental situations examined.

scholarly journals In vivo measurement of lipogenesis in ruminants using [1-14C]acetate

2001 ◽  
Vol 86 (1) ◽  
pp. 37-44 ◽  
Author(s):  
H. M. R. Greathead ◽  
J. M. Dawson ◽  
N. D. Scollan ◽  
P. J. Buttery
Keyword(s):  
Adipose Tissue ◽  
Intravenous Infusion ◽  
Subcutaneous Adipose Tissue ◽  
Acetate Incorporation ◽  
Continuous Intravenous Infusion ◽  
Tissue Lipid ◽  
Tissue Samples ◽  
Subcutaneous Adipose ◽  
Infusion Period

A method for the measurement of the rate of lipogenesis in ruminants using a continuous intravenous infusion of [1-14C]acetate and measuring the rate of [1-14C]acetate incorporation into adipose tissue lipid was evaluated. Subcutaneous adipose tissue samples obtained by biopsy over the course of a 6 h continuous intravenous infusion of [1-14C]acetate into a wether and a steer maintained in a ‘metabolic steady state’ demonstrated that the incorporation of [1-14C]acetate into subcutaneous adipose tissue lipid was linear for the duration of the infusion period. Subsequent measures of rates of [1-14C]acetate incorporation into adipose tissue lipid were made on adipose tissue samples taken at a single time point during the infusion period. The technique was used to measure rates of lipogenesis in the subcutaneous adipose tissue of fourteen Hereford × Friesian steers that had been fed a pelleted diet of dried grass at a range of metabolizable energy (ME) intakes from 1·1 × ME requirement for maintenance to ad libitum for 11 weeks. Rates of lipogenesis increased linearly (P<0·001) with increasing ME intake. It was concluded that the method is an effective technique for measuring rates of lipogenesis in specific adipose tissue depots in vivo in ruminants.

Selection against sprouting damage in wheat. III.* Dormancy, germinative alpha-amylase, grain redness and flavanols

1979 ◽  
Vol 30 (3) ◽  
pp. 387 ◽  
Author(s):  
IL Gordon
Keyword(s):  
The Other ◽  
Grain Development ◽  
Germination Inhibitors ◽  
Development Patterns ◽  
White Wheat ◽  
Long Period ◽  
Short Period ◽  
Embryo Dormancy ◽  
Different Levels

Grain development of embryo dormancy, germinative α-amylase, pigmentation and flavanols was examined in the wheats Timgalen and Gamut (white-grained, non-dormant), and Pembina and Sonora (red-grained with different levels of dormancy). It was found that each trait had distinctive patterns of development. The net result at harvest ripeness depended on the synchronizations amongst the traits. Dormancy, as judged by embryo response (i.e. embryo dormancy), was restricted to the red wheats. Three ways of expressing it were noted: (1) in terms of development patterns, (2) as levels at harvest ripeness or at harvest, and (3) by the length of the period of embryo dormancy after harvest ripeness. Two hypotheses linking embryo dormancy and grain redness appeared plausible from the results. One was that the polyphenol oxidase complex, which polymerizes flavanols to the putative pigment phlobaphene, contributes towards embryo dormancy, probably through enhancement of hypo-oxia. The other was that the pigment itself and its tanning complexes cause the hypo-oxia. Flavanols did not appear to be in vivo germination inhibitors. Dormancy, as judged by α-amylase response (i.e. amylase dormancy), was not always present together with embryo dormancy. A long period of amylase dormancy was found in the more embryo-dormant red wheat, but not in the other. Conversely, a short period of amylase dormancy was found in one white wheat, but it was not embryo-dormant. Possible relationships between these physiological traits and the classical genes for red grain-coat were discussed. Implications concerning selection against sprouting damage were considered. _________________ *Part II, Aust. J. Agric. Res 30: 1-17 (1979).

Prophylactic Efficacy and Bone Toxicity Associated with Phosphonoformate Therapy against Retrovirus Infection

1992 ◽  
Vol 3 (6) ◽  
pp. 335-343 ◽  
Author(s):  
C. L. Swenson ◽  
P. J. Polas ◽  
S. E. Weisbrode ◽  
L. A. Nagode ◽  
G. J. Kociba ◽  
...  
Keyword(s):  
Intravenous Infusion ◽  
Serum Alkaline Phosphatase ◽  
Antiviral Effect ◽  
Bone Lesions ◽  
Continuous Intravenous Infusion ◽  
Leukaemia Virus ◽  
Challenge Control ◽  
Intravenous Inoculation

Phosphonoformate (PFA) is a simple pyrophosphate analogue which is a topical and parenteral treatment for human herpes virus infections and is currently undergoing evaluation for treatment of human immunodeficiency virus (HIV) and cytomegalovirus infections associated with (AIDS). In this study, antiretroviral activity of PFA was demonstrated by two separate treatment regimens. In the first, an inoculum of feline leukaemia virus (FeLV) in plasma from viraemic cats was treated with 1024 μM PFA prior to intravenous inoculation into susceptible animals. Three of four cats given the PFA treated inoculum were protected from viraemia by the PFA treatment, while 2 of 2 challenge controls receiving sham treated inoculum and 6 of 6 untreated challenge controls became viraemic. In the second regimen, a long-term continuous intravenous infusion of PFA (1000 mg kg−1 day−1) was administered to 6 young cats beginning 1–2 days prior to and extending 4 weeks following intravenous inoculation with FeLV. Five of the six PFA-treated cats also received heparin intravenously and acetyl salicylic acid (aspirin) orally to reduce risk of thrombosis. Six cats (heparin controls) received only heparin and aspirin and were inoculated with FeLV in an identical manner. Six cats served as untreated challenge controls. Four of 6 PFA-treated cats were protected from FeLV antigenaemia. In contrast, all 6 heparin-control animals and all 6 challenge-control animals became persistently viraemic as evidenced by continuous expression of FeLV p27 antigen. All challenged cats including the 4 protected by PFA treatment developed antibody to FeLV, indicating that PFA did not prevent primary virus infection. Significant toxic effects of PFA treatment were reduced weight-gain and rickets-like bone lesions in the cats receiving the 4 week treatment. Additionally, decreased serum alkaline phosphatase, phosphorus, and calcitriol concentrations, presumably related to the bone lesions, were observed. Results of this study suggest that the antiviral effect of PFA involves an immediate and direct mechanism targeted at cell-free virus and that long-term continuous intravenous infusion of PFA has significant anti-retroviral activity in vivo.

Platelet Involvement After Myocardial Infarction

1979 ◽  
Author(s):  
J.R. O’Brien ◽  
R.I. Handin ◽  
M.D. Etherington ◽  
R.D. Shuttleworth ◽  
W. Calwell
Keyword(s):  
Myocardial Infarction ◽  
Inverse Correlation ◽  
The Other ◽  
Interim Report ◽  
Clotting Time ◽  
Enzymatic Process ◽  
Acid Glycoprotein ◽  
The Mean

After myocardial Infarction (MI) the Heparin Thrombin Clotting Time (HTCT) of platelet (plt) poor plasma is short, indicating an increase in Heparin Neutralizing Activity (HNA). Plt. Factor 4 (PF4) released in vitro also neutralizes heparin. Does the plasma HTCT in MI reflect PF4 released in vivo? Fifteen patients with MI were compared with 23 controls. The mean HTCT was 43.9 sees, in controls and 14.8 sees, in patients. Plasma PF4 measured by RIA was abnormal in 3 patients but strictly normal in the other 12 (n = 12, mean 3.96 ng/ml; controls n = 22, mean 3.54). There was no correlation between the plasma PF4 and the HTCT. The plts, were frozen and thawed and the patients’ plts, released less HNA (0.17 units/109 plts.) relative to the controls (0.70 units/109plts.) and there was a tight inverse correlation between the plasma HTCT and the intra-plt. HNA. Plts, were isolated and stimulated maximally with thrombin; then malondialdehyde (MDA) production reflecting PG synthesis was monitored fluorometrically. Patients liberated less MDA. (415 ng/109plts.) than the controls (911 ng/plts.). All differences are significant, except the PF4. Plasma fibrinogen and α1 acid glycoprotein were also measured. Thus after an MI and presumably as a result of it, plts, are damaged or “exhausted” as reflected both by a decrease in an enzymatic process - PG synthesis and by a decrease in the content of HNA (? PF4). This interim report also clearly demonstrates that the plasma HTCT does not reflect the same attribute as plasma PF4 detected by RIA.

Immunologie Studies in von Willebrand’s Disease

1976 ◽  
Vol 35 (01) ◽  
pp. 110-119 ◽  
Author(s):  
Y Sultan ◽  
J Simeon ◽  
P Maisonneuve ◽  
J. P Caen
Keyword(s):  
Factor Viii ◽  
Bleeding Time ◽  
The Other ◽  
Von Willebrand's Disease ◽  
Factor Viii Related Antigen ◽  
Von Willebrand’S Disease ◽  
Short Period ◽  
Von Willebrand ◽  
Immunologic Properties

SummaryTwo patients with a severe von Willebrand’s disease characterized by no detectable factor VIII related antigen in their plasma received transfusions of cryoprecipitate. The bleeding time was corrected for a short period of time and returned to its pretransfusional value although the other parameters of the disease were still corrected. Electrophoretic and immunologic properties of factor VIII related antigen infused were determined serially after transfusion. Modifications of these properties occurred progressively after transfusion. The half disappearance time of F. VIIIR. A. was determined and found to be considerably shorter than in hemophilic recipients. This study suggests an alteration in vivo of F. VIIIR. A. infused into von Willebrand recipients.

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