Time course study of the in vivo synthesis of avian liver pteroylpoly-γ-glutamates

1977 ◽  
Vol 30 (10) ◽  
pp. 1576-1582 ◽  
Author(s):  
R W Thompson ◽  
C L Krumdieck
Keyword(s):  
Time Course ◽  
Time Course Study ◽  
In Vivo Synthesis

Thymocyte/stromal cell chimaerism in allothymus-grafted Xenopus: developmental studies using the X. borealis fluorescence marker

Development ◽  
1987 ◽  
Vol 100 (1) ◽  
pp. 107-117
Author(s):  
J.D. Horton ◽  
J.H. Russ ◽  
P. Aitchison ◽  
T.L. Horton
Keyword(s):  
Stromal Cell ◽  
Time Course ◽  
Adult Life ◽  
Cell Types ◽  
Lymphoid Cells ◽  
Host Cells ◽  
Developmental Studies ◽  
Stage Of Development ◽  
Time Course Study

These experiments employ the X. borealis (quinacrine-fluorescence) cell marker to illustrate that froglet (normal or in vivo-irradiated) thymuses, alloimplanted to 4- to 6-week-old, 7-day-thymectomized hosts, become filled with host lymphoid cells, while a range of thymic stromal cell types (e.g. epithelial derivatives and reticuloendothelial cells) remain donor derived. A time-course study of 4 micron historesin-embedded sections reveals that for normal thymus implants, host cells begin to immigrate in good number only after metamorphosis. In contrast, 3000 rad-irradiated thymus implants begin to be repopulated with host lymphocytes within 2 weeks postimplantation, when hosts are still at a late larval stage of development. Despite rapid colonization by host lymphoid cells, irradiated thymuses remain small and often disappear in early adult life. Donor-derived lymphocytes frequent the blood and both the red pulp and perifollicular regions of the spleen following normal thymus implantation, whereas such thymic emigrants were not seen in the periphery of thymectomized hosts grafted with irradiated thymus glands.

In vivo protection studies of bis-quaternary 2-(hydroxyimino)-N-(pyridin-3-yl) acetamide derivatives against sarin poisoning in mice

2016 ◽  
Vol 36 (1) ◽  
pp. 23-32 ◽  
Author(s):  
Devyani Swami ◽  
Hitendra N Karade ◽  
Jyotiranjan Acharya ◽  
Pravin Kumar
Keyword(s):  
Time Course ◽  
Lethal Dose ◽  
Nerve Agent ◽  
Ache Inhibition ◽  
Inhibition Concentration ◽  
Time Course Study ◽  
Dose Dependent ◽  
Protection Index ◽  
Lethal Doses

In vivo antidotal efficacy of new bis- quaternary 2-(hydroxyimino)- N-(pyridin-3yl) acetamide derivatives (HNK series), to counter multiples of lethal doses of nerve agent sarin (GB) and reactivation of acetylcholinesterase (AChE), was evaluated in Swiss albino mice. [Protection index PI; median lethal dose (LD50) of sarin with treatment/LD50 of sarin] was estimated, using 0.05, 0.10, and 0.20 LD50 as treatment doses of all the oximes with atropine against sarin poisoning. Dose-dependent time course study was conducted at 0.2, 0.4 and 0.8 LD50 dose of sarin for estimating maximum AChE inhibition. At optimized time (15 min), in vivo enzyme half inhibition concentration (IC50) was calculated. AChE reactivation efficacy of HNK series and pralidoxime (2-PAM) were determined by plotting shift of log IC50 doses. HNK-102 with atropine showed three fold higher PI compared to 2-PAM. In vivo IC50 of sarin for brain and serum AChE was found to be 0.87 LD50 (139.2 µg/kg) and 0.48 LD50 (77.23 µg/kg), respectively. Treatment with HNK-102 and HNK-111 (equal to their 0.20LD50) significantly reactivated sarin-intoxicated AChE ( p < 0.05) at 2× IC50 dose of sarin, compared to 2-PAM. The study revealed that HNK-102 oxime was three times more potent as antidote, for acute sarin poisoning compared to 2-PAM in vivo.

scholarly journals The regulation of lipogenesis in vivo in the lactating mammary gland of the rat during the starved-refed transition. Studies wtih acarbose, a glucosidase inhibitor

1987 ◽  
Vol 242 (1) ◽  
pp. 235-243 ◽  
Author(s):  
S W Mercer ◽  
D H Williamson
Keyword(s):  
Mammary Gland ◽  
Time Course ◽  
Chow Diet ◽  
Glucosidase Inhibitor ◽  
Lactating Mammary Gland ◽  
Phosphofructokinase Activity ◽  
Time Course Study ◽  
Fructose 1,6 Bisphosphate

Depression of carbohydrate digestion by oral administration of acarbose, a glucosidase inhibitor, led to a 75% inhibition of the re-activation of lipogenesis in vivo in the mammary gland of 18 h-starved lactating rats refed with 5 g of chow diet. Rates of [1-14C]glucose incorporation in vitro into lipid and CO2 in mammary-gland acini isolated from refed animals were elevated compared with acini from starved rats, but acarbose treatment completely prevented this stimulation. Gastric intubation of glucose led to a large stimulation of lipogenesis in the mammary gland of starved lactating rats, similar to that induced by refeeding with chow diet; this was dependent on the amount of glucose given and the time elapsed between glucose administration and injection of 3H2O for the measurement of lipogenesis. The switch-on of lipogenesis in the mammary gland of starved lactating rats, by refeeding or by intubation of glucose, was associated with a decrease in the ratio of [glucose 6-phosphate]/[fructose 1,6-bisphosphate] in the gland, indicative of an increase in phosphofructokinase activity. A time-course study revealed that the ratio decreased rapidly over the first 30 min of chow refeeding, after which a large surge in lipogenesis was seen. Acarbose, given 25 min after the onset of refeeding, led to a stepwise increase in the ratio, in parallel with the observed decrease in lipogenic activity. It is concluded that the control of lipogenesis in the mammary gland is closely linked to the availability of dietary carbohydrate. An important site of regulation of lipogenesis in the gland appears to be at the level of phosphofructokinase. A possible role of insulin in the regulation of phosphofructokinase activity, and the acute modulation of insulin-sensitivity in the gland during the starved-refed transition, are discussed.

Longitudinal in vivo and in vitro time-course study of chronic cerebrovasospasm in the rabbit basilar artery

1991 ◽  
Vol 14 (3) ◽  
pp. 215-219 ◽  
Author(s):  
Peter Vorkapic ◽  
John A. Bevan ◽  
Rosemary D. Bevan
Keyword(s):  
Basilar Artery ◽  
Time Course ◽  
Time Course Study

scholarly journals 13C tracer analysis identifies extensive recycling of endogenous CO2 in vivo

2021 ◽  
Author(s):  
Likun Duan ◽  
Daniel E. Cooper ◽  
Grace Scheidemantle ◽  
Jason W. Locasale ◽  
David G. Kirsch ◽  
...  
Keyword(s):  
Time Course ◽  
Cultured Cells ◽  
Tca Cycle ◽  
Data Interpretation ◽  
Carboxylase Activity ◽  
Intact Cells ◽  
Time Course Study ◽  
Metabolic Activities

Abstract13C tracing analysis is increasingly used to monitor cellular metabolism in vivo and in intact cells, but data interpretation is still the key element to unveil the complexity of metabolic activities. We have performed [U-13C]-glucose and [U-13C]-glutamine tracing in sarcoma-bearing mice (in vivo) and in cancer cell lines (in vitro). 13C enrichment of metabolites in cultured cells and tissues was determined by liquid chromatography coupled with high-resolution mass spectrometer (LC-HRMS). As expected, citrate M+2 or M+4 is the dominant mass isotopologue in vitro. However, citrate M+1 was unexpectedly the dominant isotopologue in mice receiving [U-13C]-glucose or [U-13C]-glutamine infusion. One plausible explanation is that 13CO2 produced from the oxidation of 13C tracers in vitro is negligible due to the dilution of HCO3- supplemented to cell culture when sodium bicarbonante is used and diffusible volume of CO2 in the culture incubator, while endogenous 13CO2 in vivo is substantial and is fixed into the TCA cycle, purine, and serine, resulting in M+1 isotopologues. A time course study shows the generation of high abundance citrate M+1 early in plasma, which may serve as a potent non-invasive biomarker of tissue pyruvate carboxylase activity. Altogether, our results show that recycling of endogenous CO2 is substantial in vivo and provides important insights into the experimental design and data interpretation of 13C tracing assays.

scholarly journals The in vivo and in vitro transmission frequencies of the tw5-haplotype in mice

1989 ◽  
Vol 53 (1) ◽  
pp. 21-24 ◽  
Author(s):  
William Garside ◽  
Nina Hillman
Keyword(s):  
Time Course ◽  
Phenotypic Expression ◽  
Transmission Frequency ◽  
High Frequencies ◽  
Heterozygous Male ◽  
Time Course Study ◽  
Very High Frequencies ◽  
Very High

SummaryThe recessive tω5-haplotype, a complete haplotype, is transmitted by heterozygous male mice at very high frequencies (> 0·90) in normal matings. The present studies were undertaken to determine the effects of delayed matings and in vitro fertilizations on this phenotypic expression. Males carrying the tω5-haplotype ( + / tω5) were first tested for their frequencies of transmission of the mutant 17th chromosome in both normal and delayed matings. Spermatozoa obtained from these same males were then used to fertilize eggs in vitro. The in vivo and in vitro transmission frequencies were found to be statistically equivalent in all types of inseminations. An in vitro fertilization time course study showed that the same percentages of eggs are fertilized by tω5- bearing spermatozoa when the gametes are coincubated for either 2 or 6 h. The data lead to the conclusion that the transmission frequency of the tω5-haplotype is not affected either by the length of time elapsing between insemination and fertilization or by the environment in which fertilization occurs.

scholarly journals Cholesterol and mevalonate metabolism: a time course study in vivo

1961 ◽  
Vol 2 (4) ◽  
pp. 344-349
Author(s):  
J.C. Elwood ◽  
J.T. Van Bruggen
Keyword(s):  
Time Course ◽  
Time Course Study

Comparison of High Purity Factor IX Concentrates and a Prothrombin Complex Concentrate in a Canine Model of Thrombogenicity

1991 ◽  
Vol 66 (05) ◽  
pp. 609-613 ◽  
Author(s):  
I R MacGregor ◽  
J M Ferguson ◽  
L F McLaughlin ◽  
T Burnouf ◽  
C V Prowse
Keyword(s):  
High Purity ◽  
Time Course ◽  
Prothrombin Complex Concentrate ◽  
Degradation Products ◽  
Canine Model ◽  
Factor Ix ◽  
In Vitro Tests ◽  
Albumin Infusion

SummaryA non-stasis canine model of thrombogenicity has been used to evaluate batches of high purity factor IX concentrates from 4 manufacturers and a conventional prothrombin complex concentrate (PCC). Platelets, activated partial thromboplastin time (APTT), fibrinogen, fibrin(ogen) degradation products and fibrinopeptide A (FPA) were monitored before and after infusion of concentrate. Changes in FPA were found to be the most sensitive and reproducible indicator of thrombogenicity after infusion of batches of the PCC at doses of between 60 and 180 IU/kg, with a dose related delayed increase in FPA occurring. Total FPA generated after 100-120 IU/kg of 3 batches of PCC over the 3 h time course was 9-12 times that generated after albumin infusion. In contrast the amounts of FPA generated after 200 IU/kg of the 4 high purity factor IX products were in all cases similar to albumin infusion. It was noted that some batches of high purity concentrates had short NAPTTs indicating that current in vitro tests for potential thrombogenicity may be misleading in predicting the effects of these concentrates in vivo.

Time Course Change of the Heat-generating Capability of Dextran Magnetite Complex (DM) in vivo.

2001 ◽  
Vol 17 (2) ◽  
pp. 85-91 ◽  
Author(s):  
MICHIHIDE MITSUMORI ◽  
TORU SHIBATA ◽  
YASUSHI NAGATA ◽  
MASAHIRO HIRAOKA ◽  
MASAKATSU HASEGAWA ◽  
...  
Keyword(s):  
Time Course
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