Tissue-specific differences in the compartmentalization of rat nuclear triiodothyronine receptors

1990 ◽  
Vol 122 (2) ◽  
pp. 181-190 ◽  
Author(s):  
Charles P. Barsano ◽  
Zafar Iqbal ◽  
Gordon L. Pullen ◽  
B. Elena Muñoz ◽  
Sant P. Singh
Keyword(s):  
Nuclear Receptors ◽  
Rank Order ◽  
Glass Wool ◽  
Association Constants ◽  
Small Samples ◽  
Nuclear Compartment ◽  
Hormone Responsiveness

Abstract In addition to the recognized rat liver nuclear T3 receptor extractable with hypertonic salt, recent studies have described nucleoplasmic receptors extractable with isotonic KCl and salt-resistant receptors localized to the nuclear matrix. A method was developed for the determination of intra-nuclear receptor distribution 1in small samples of nuclei dispersed within glass wool matrices. After in vitro labelling with 6 nmol/l [125I]T3, dispersed nuclei were sequentially extracted with 0.15 mol/l KCl (yielding nucleoplasmic receptors), 0.4 mol/l KCl, and 2 mol/l KCl (the latter two concentrations yelding hypertonic salt-extractable receptors). The salt-resistant receptors were retained within the glass wool columns. The intra-nuclear distribution of in vivo labelled receptors was very similar to that obtained by in vitro labelling. The equilibrium association constants for L-T3 binding among the receptor pools ranged from 0.6 × 109 to 1.0 × 109 l/mol. The distribution of total nuclear receptors within each nuclear compartment was (percentage of nucleoplasmic, hypertonic salt-extractable, and salt-resistant receptors): Cerebrum: 23.6, 52.2, 24.2; Liver: 25.2, 57.2, 17.5; Kidney: 45.9, 33.5, 20.6; Testis: 65.5, 14.7, 19.7; and Spleen: 66.7, 18.7, 14.6. The rank order of percentage of hypertonic salt-extractable receptors approximates the rank order of thyroid hormone-responsiveness by traditional criteria. The inverse is true for the percentage of nucleoplasmic receptors. The percentage of salt-resistant receptors was very similar in all of the tissues.

scholarly journals Measurement of Bmax and Kd with the Glycine Transporter 1 Radiotracer 18F-MK6577 using a Novel Multi-Infusion Paradigm

2015 ◽  
Vol 35 (12) ◽  
pp. 2001-2009 ◽  
Author(s):  
Yan Xia ◽  
Ming-Qiang Zheng ◽  
Daniel Holden ◽  
Shu-fei Lin ◽  
Michael Kapinos ◽  
...  
Keyword(s):  
Rank Order ◽  
Target Concentration ◽  
Glycine Transporter 1 ◽  
Glycine Transporter ◽  
Positron Emission ◽  
Fitting Method ◽  
The Brain

Glycine is a co-agonist of glutamate at the NMDA receptor. Glycine transporter 1 (GlyT1) inhibitors are reported to be potential therapeutic agents for schizophrenia. 18F-MK6577 is a new positron emission tomography (PET) radiotracer useful for imaging brain GlyT1 and its occupancy in humans. We devised a novel multi-infusion paradigm of radiolabeled and unlabeled compound and an iterative linear/nonlinear alternating fitting method to allow for the determination of in vivo affinity ( Kd) and target concentration ( Bmax) images, constraining Kd to be uniform across the brain. This paradigm was tested with 18F-MK6577 in baboons. Voxel-based analysis produced high quality Bmax images and reliable Kd estimates, and also suggested that the nondisplaceable distribution volume ( VND) is not uniform throughout the brain. In vivo GlyT1 Kd was estimated to be 1.87 nmol/L for 18F-MK6577, and the rank order of GlyT1 distribution measured in the baboon brain was: high in the brainstem (133 nmol/L), medium in the cerebellum (83 nmol/L), and low in the cortex (30 nmol/L). These in vivo Kd and Bmax values agreed well with those determined in vitro, thus validating our novel multi-infusion approach.

5-Hydroxytryptamine (serotonin) in acute hypotensive shock

1964 ◽  
Vol 207 (1) ◽  
pp. 215-222 ◽  
Author(s):  
Roy L. Swank ◽  
Wolfgang Hissen ◽  
J. H. Fellman
Keyword(s):  
Blood Cell ◽  
Blood Cells ◽  
Cell Aggregation ◽  
Glass Wool ◽  
Fluorometric Determination ◽  
Platelet Counts ◽  
Blood Cell Aggregation

Alterations in the circulating 5-hydroxytryptamine (5-HT), platelet counts, and the degree of blood cell aggregation were studied before and during acute hypotensive "shock," induced either by bleeding or by histamine injections in anesthetized and heparinized dogs. Although marked aggregation of blood cells was observed during shock only slight increases in 5-HT and platelet counts were found. Since earlier studies in vitro had indicated a direct relationship between aggregation of blood cells and 5-HT the reliability of the fluorometric determination of 5-HT was questioned. Subsequent experiments with C14-labeled 5-HT showed increases up to 600% in circulating radioactivity during hypotension, representing 5-HT, or its metabolites. Radioactivity increased earlier and was greatest in portal blood. Glass-wool filtration experiments showed that adhesive platelets were important in the mechanism of blood cell aggregation. UML-491, a 5-HT and blood aggregation inhibitor in vitro, was shown to prevent or lower the tendency of blood cells to aggregate in vivo during hemorrhage. These experiments indicate the importance of 5-HT in the development of blood cell aggregation during shock, and its prevention by a 5-HT antagonist.

A Molecular Approach to Immunoscintigraphy: A Study of the T-Antigen Conformation on the Surface of Tumors

1987 ◽  
Vol 26 (01) ◽  
pp. 1-6 ◽  
Author(s):  
S. Selvaraj ◽  
M. R. Suresh ◽  
G. McLean ◽  
D. Willans ◽  
C. Turner ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Tumor Cell ◽  
T Antigen ◽  
Human Carcinomas ◽  
Animal Tumor ◽  
Synthetic Antigens

The role of glycoconjugates in tumor cell differentiation has been well documented. We have examined the expression of the two anomers of the Thomsen-Friedenreich antigen on the surface of human, canine and murine tumor cell membranes both in vitro and in vivo. This has been accomplished through the synthesis of the disaccharide terminal residues in both a and ß configuration. Both entities were used to generate murine monoclonal antibodies which recognized the carbohydrate determinants. The determination of fine specificities of these antibodies was effected by means of cellular uptake, immunohistopathology and immunoscintigraphy. Examination of pathological specimens of human and canine tumor tissue indicated that the expressed antigen was in the β configuration. More than 89% of all human carcinomas tested expressed the antigen in the above anomeric form. The combination of synthetic antigens and monoclonal antibodies raised specifically against them provide us with invaluable tools for the study of tumor marker expression in humans and their respective animal tumor models.

Storage of Human Blood Platelets

1974 ◽  
Vol 32 (02/03) ◽  
pp. 405-416 ◽  
Author(s):  
M. R Hardeman ◽  
Carina J L. Heynens
Keyword(s):  
Storage Temperature ◽  
Platelet Rich Plasma ◽  
Blood Platelets ◽  
Storage Period ◽  
Serotonin Uptake ◽  
Hypotonic Shock ◽  
Glycolytic Intermediates

SummaryStorage experiments were performed at 4°, 25° and 37° C with platelet-rich plasma under sterile conditions. In some experiments also the effect of storing platelets at 4° C in whole blood was investigated.Before, during and after three days of storage, the platelets were tested at 37° C for their serotonin uptake and response to hypotonic shock. In addition some glycolytic intermediates were determined.A fair correlation was noticed between the serotonin uptake and hypotonic shock experiments. Both parameters were best maintained at 25° C. Also platelet counting, performed after the storage period, indicated 25° C as the best storage temperature. Determination of glycolytic intermediates did not justify any conclusion regarding the optimal storage temperature. Of the various anticoagulants studied, ACD and heparin gave the best results as to the serotonin uptake and hypotonic shock response, either with fresh or stored platelets. The use of EDTA resulted in the lowest activity, especially after storage.The results of these storage experiments in vitro, correspond well with those in vivo reported in the literature.

Carbon dots derived from Fusobacterium nucleatum for intracellular determination of Fe3+ and bioimaging both in vitro and in vivo

2021 ◽  
Author(s):  
Lijuan Liu ◽  
Shengting Zhang ◽  
Xiaodan Zheng ◽  
Hongmei Li ◽  
Qi Chen ◽  
...  
Keyword(s):  
Carbon Dots ◽  
Fusobacterium Nucleatum ◽  
Living Cells ◽  
First Time ◽  
Fluorescent Carbon Dots ◽  
Fluorescent Carbon

Fusobacterium nucleatum has been employed for the first time to synthesize fluorescent carbon dots which could be applied for the determination of Fe3+ ions in living cells and bioimaging in vitro and in vivo with excellent biocompatibility.

Factors affecting in vitro and in vivo antioxidant effects. Experimental conditions and nature of oxidants determine antioxidant efficacy

2021 ◽  
pp. 1-9
Author(s):  
Etsuo Niki
Keyword(s):  
Biological Molecules ◽  
Experimental Conditions ◽  
Factors Affecting ◽  
Beneficial Effects ◽  
Multiple Oxidants ◽  
Antioxidant Effects

Reactive oxygen and nitrogen species have been implicated in the onset and progression of various diseases and the role of antioxidants in the maintenance of health and prevention of diseases has received much attention. The action and effect of antioxidants have been studied extensively under different reaction conditions in multiple media. The antioxidant effects are determined by many factors. This review aims to discuss several important issues that should be considered for determination of experimental conditions and interpretation of experimental results in order to understand the beneficial effects and limit of antioxidants against detrimental oxidation of biological molecules. Emphasis was laid on cell culture experiments and effects of diversity of multiple oxidants on antioxidant efficacy.

Antimicrobial and antibiofilm activities of meropenem loaded-mesoporous silica nanoparticles against carbapenem-resistant Pseudomonas aeruginosa

2021 ◽  
pp. 088532822110038
Author(s):  
Mohammad Yousef Memar ◽  
Mina Yekani ◽  
Hadi Ghanbari ◽  
Edris Nabizadeh ◽  
Sepideh Zununi Vahed ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Mesoporous Silica ◽  
Silica Nanoparticles ◽  
Mesoporous Silica Nanoparticles ◽  
Carbapenem Resistant ◽  
Toxicity In Vitro ◽  
Different Levels

The aims of the present study were the determination of antimicrobial and antibiofilm effects of meropenem-loaded mesoporous silica nanoparticles (MSNs) on carbapenem resistant Pseudomonas aeruginosa ( P. aeruginosa) and cytotoxicity properties in vitro. The meropenem-loaded MSNs had shown antibacterial and biofilm inhibitory activities on all isolates at different levels lower than MICs and BICs of meropenem. The viability of HC-04 cells treated with serial concentrations as MICs and BICs of meropenem-loaded MSNs was 92–100%. According to the obtained results, meropenem-loaded MSNs display the significant antibacterial and antibiofilm effects against carbapenem resistant and biofilm forming P. aeruginosa and low cell toxicity in vitro. Then, the prepared system can be an appropriate option for the delivery of carbapenem for further evaluation in vivo assays.

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