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International Journal of Molecular... Sep 2022A simple but efficient computational approach to calculate p in acetonitrile for a set of phosphorus, nitrogen, and carbon bases was established. A linear function that...
A simple but efficient computational approach to calculate p in acetonitrile for a set of phosphorus, nitrogen, and carbon bases was established. A linear function that describes relations between the calculated Δ'(BH) and p values was determined for each group of bases. The best model was obtained through the variations in the basis set, in the level of theory (density functionals or MP2), and in the continuum solvation model (IPCM, CPCM, or SMD). The combination of the IPCM/B3LYP/6-311+G(d,p) solvation approach with MP2/6-311+G(2df,p)//B3LYP/6-31G(d) gas-phase energies provided very good results for all three groups of bases with R values close to or above 0.99. Interestingly, the slopes and the intercepts of the obtained linear functions showed significant deviations from the theoretical values. We made a linear plot utilizing all the conducted calculations and all the structural variations and employed methods to prove the systematic nature of the intercept/slope dependence. The interpolation of the intercept to the ideal slope value enabled us to determine the Gibbs energy of the proton in acetonitrile, which amounted to -258.8 kcal mol. The obtained value was in excellent agreement with previously published results.
Topics: Acetonitriles; Carbon; Chlormerodrin; Nitrogen; Phosphorus; Protons; Thermodynamics
PubMed: 36142490
DOI: 10.3390/ijms231810576 -
Journal of Nuclear Medicine : Official... Mar 1984
Comparative Study
Topics: Administration, Oral; Animals; Brain; Brain Diseases; Chlormerodrin; Half-Life; Humans; Injections, Intravenous; Iodine Radioisotopes; Kinetics; Mercury Radioisotopes; Mice; Radiation Dosage; Radionuclide Imaging; Rats; Sodium Pertechnetate Tc 99m; Technetium; Tissue Distribution
PubMed: 6321702
DOI: No ID Found -
Journal of Nuclear Medicine : Official... Apr 1981The renal extraction efficiencies for various radioactive agents were measured in normal anesthetized dogs during 1 hr after a single intravenous injection. Radioassays... (Comparative Study)
Comparative Study
The renal extraction efficiencies for various radioactive agents were measured in normal anesthetized dogs during 1 hr after a single intravenous injection. Radioassays were made on serial blood samples drawn simultaneously from the aorta upstream from the renal arteries and from one renal vein. As a reference substance [131I]o-iodohippurate was injected concurrently in all experiments. Blood clearances from serial venous samples and urinary excretion also were measured. Extraction efficiency from whole blood was calculated as (A-V) divided by A, where A = aortic concentration and V = renal venous concentration. This ratio for commercial [131I]o-iodohippurate fell steadily from 88% at 30 sec to 50% at 1 hr. For "purified" [131I]o-iodohippurate the fall was less marked, to 61% at 1 hr. The EE ratios for all other agents were stable after the first minute. The Tc-99m complexes of DTPA, glucoheptonate, and acetylcysteine had ratios averaging 27-29%. The ratios of Tc-99m DMS and Hg-197 chlormerodrin had much lower average values of 8 and 14%, respectively. None of the newer agents approached the extraction efficiency of [131I]o-iodohippurate.
Topics: Animals; Aorta; Bone and Bones; Dogs; Iodohippuric Acid; Kidney; Radionuclide Imaging; Reference Values; Renal Artery; Renal Veins; Technetium; Technology, Pharmaceutical; Time Factors
PubMed: 7205379
DOI: No ID Found -
Selective effects of organic mercurials on the GTP-regulatory proteins of adenylate cyclase systems.The Journal of Biological Chemistry Aug 1980Treatment of membranes from HeLa cells, rat adipocytes, and rat liver with organic mercurials results in complex effects on adenylate cyclase activity that are not... (Comparative Study)
Comparative Study
Treatment of membranes from HeLa cells, rat adipocytes, and rat liver with organic mercurials results in complex effects on adenylate cyclase activity that are not mimicked by the reversible sulfhydryl reagent, tetrathionate. At low concentrations (0.1 mM or less 1 mercurials inactivate the enzyme; inactivation is reversed by the thiol-reducing agent, dithiothreitol. Treatment with higher concentrations of organic mercurials (1 mM and above) results in a time-dependent, irreversible change in the ability of guanine nucleotides and fluoride ion to stimulate adenylate cyclase activity. The irreversible changes are blocked by treatment of membranes with cholera toxin and NAD, suggesting that the GTP-regulatory component is the site of mercurial action. This is further suggested by the lack of irreversible effects of mercurials on adenylate cyclase activity in membranes from mouse lymphoma cells that lack this component. Irreversible effects of mercurials on the adipocyte cyclase system also include enhancement of basal activity and potentiation of the inhibitory effects of GTP on cyclase activity; the latter effects of GTP are mediated through a process independent from that mediating stimulation of activity by GTP. It is concluded that the GTP-regulatory proteins responsible for the modulation of adenylate cyclase activity by hormones and neurotransmitters contain the sites of action of organic mercurials. Their possible mode of action is discussed.
Topics: Adenylyl Cyclases; Adipose Tissue; Animals; Carrier Proteins; Cell Line; Cell Membrane; Chlormerodrin; Cholera Toxin; Dithiothreitol; GTP-Binding Proteins; Guanosine Triphosphate; HeLa Cells; Humans; Kinetics; Liver; Lymphoma; Mice; Organ Specificity; Rats; Tetrathionic Acid
PubMed: 6771284
DOI: No ID Found -
Journal of Nuclear Medicine : Official... Jan 1979Computer-assisted static/dynamic renal imaging with [197Hg] chlormerodrin and [99mTc]pertechnetate was evaluated prospectively as a screening test for renovascular... (Comparative Study)
Comparative Study
Computer-assisted static/dynamic renal imaging with [197Hg] chlormerodrin and [99mTc]pertechnetate was evaluated prospectively as a screening test for renovascular hypertension. Results are reported for 51 patients: 33 with benign essential hypertension and 18 with renovascular hypertension, and for 21 normal controls. All patients underwent renal arteriography. Patients with significant obesity, renal insufficiency, or renoparenchymal disease were excluded from this study. Independent visual analyses of renal gamma images and time-activity transit curves identified 17 of the 18 patients with renovascular hypertension; one study was equivocal. There were five equivocal and three false-positive results in the essential hypertension and normal controls groups. The sensitivity of the method was 94% and the specificity 85%. Since the prevalence of the renovascular subset of hypertension is approximately 5%, the predictive value is only 25%. Inclusion of computer-generated data did not improve this result. Accordingly, this method is not recommended as a primary screening test for renovascular hypertension.
Topics: Adult; Chlormerodrin; Computers; Evaluation Studies as Topic; Humans; Hypertension; Hypertension, Renal; Mercury Radioisotopes; Middle Aged; Prospective Studies; Radionuclide Imaging; Technetium; Time Factors
PubMed: 430172
DOI: No ID Found -
Journal of Nuclear Medicine : Official... Mar 1977A relatively simple dual-tracer method for measuring renal extraction fraction was compared with the direct method. In the dual-tracer method an extracted and...
A relatively simple dual-tracer method for measuring renal extraction fraction was compared with the direct method. In the dual-tracer method an extracted and nonextracted tracer are mixed together and administered into the arterial circuit and samples of venous blood are obtained. The ratio of recovered to injected tracer then determines the extraction fraction. In the direct method tracer is administered directly into the renal artery and the total venous effluent is collected. Extraction fraction is then calculated as arteriovenous difference divided by the quantity injected. In our experiments the extraction for 201Tl and 203Hg-chlormerodrin were determined. The extraction fraction for 201Tl averaged 81 +/- 5% by the direct method and 81 +/- 6% by the dual-tracer technique (r = 0.94). The extraction fraction for 203Hg-chlormerodrin was found to change as a function of the renal blood flow. At normal flow the extraction fraction averaged 48% by the direct method and 45% by the dual-tracer technique. At reduced flow, in contrast, it averaged 78% by the direct method and 71% by the dual-tracer technique.
Topics: Animals; Blood Physiological Phenomena; Chlormerodrin; Dogs; Humans; Kidney; Mercury Radioisotopes; Methods; Radioactive Tracers; Radioisotopes; Regional Blood Flow; Thallium
PubMed: 839269
DOI: No ID Found -
Journal of Nuclear Medicine : Official... May 1976Superimposition of an adrenal scan on a renal scan revealed a kidney defect not appreciated on the renal scan alone. The defect proved to be ischemia of the upper pole...
Superimposition of an adrenal scan on a renal scan revealed a kidney defect not appreciated on the renal scan alone. The defect proved to be ischemia of the upper pole of the kidney. Resection of the lesion alleviated the patient's hypertension.
Topics: Adrenal Glands; Chlormerodrin; Cholesterol; Female; Humans; Hypertension, Renal; Iodine Radioisotopes; Ischemia; Kidney; Mercury Radioisotopes; Middle Aged; Radionuclide Imaging
PubMed: 1262942
DOI: No ID Found -
Journal of Nuclear Medicine : Official... Nov 1975
Topics: Body Burden; Chlormerodrin; Humans; Kidney; Mercury Radioisotopes; Radiation Dosage
PubMed: 1185275
DOI: No ID Found -
Journal of Nuclear Medicine : Official... May 1975The distribution of 17 different agents for renal imaging was compared in the rabbit by organ radioassay at 1 hr. Similarly, 99mTc complexes of iron-ascorbate,... (Comparative Study)
Comparative Study
The distribution of 17 different agents for renal imaging was compared in the rabbit by organ radioassay at 1 hr. Similarly, 99mTc complexes of iron-ascorbate, glucoheptonate (GHA) and 2,3-dimercaptosuccinic acid (DMS), and 203Hg-chlormerodrin were compared in the dog. The distribution of 99mTc-GHA and DMS was assessed in the human by blood and urinary clearance, external renal measurements, and scintillation camera imaging, and compared with older renal radiopharmaceuticals. Radiation dose estimates, based chiefly on human data, were calculated. Technetium-99m-DMS reaches a high concentration in the renal cortex and its urinary excretion rate and blood clearance are slow. It is excellent for imaging the renal parenchyma without activity in pelvocalyceal collecting system. However, it readily oxidizes and must be used within 30 min of preparation. The biologic distribution of 99mTc-GHA is similar to gluconate and iron-ascorbate complex. Its renal concentration is not as great as that of DMS but its blood and urinary clearances are much faster, resulting in lower radiation doses to most organs. Early camera images with this agent usually demonstrate both the renal parenchyma and collecting system. In later images, ther is excellent demonstration of the parenchyma alone, superior to that obtained with 99mTc-Sn-DTPA. It is a very stable complex and may be used for at least 5 hr after preparation. All radioactive renal agents examined to date have a significant concentration in the liver, making an accurate quantitative comparison between the two kidneys difficult.
Topics: Albumins; Animals; Chlormerodrin; Dogs; Gluconates; Humans; Inulin; Kidney Diseases; Male; Mannitol; Mercury Radioisotopes; Pentetic Acid; Rabbits; Radionuclide Imaging; Succinates; Sugar Acids; Technetium; Tin
PubMed: 1194986
DOI: No ID Found -
Journal of Nuclear Medicine : Official... Mar 1975Sixteen radiopharmaceuticals for brain tumor localization have been compared in a mouse brain tumor model. A rating system is presented for such intercomparison. The... (Comparative Study)
Comparative Study
Sixteen radiopharmaceuticals for brain tumor localization have been compared in a mouse brain tumor model. A rating system is presented for such intercomparison. The rusults indicate that 111-in-chloride injected at pH 1.5 has the most favorable biologic characterisTICS FOR BRAIN TUMOR IMAGING.
Topics: Animals; Ascorbic Acid; Bleomycin; Brain Neoplasms; Chlormerodrin; Gallium; Indium; Iron; Mercury Isotopes; Methylcholanthrene; Mice; Neoplasm Transplantation; Pentetic Acid; Radioisotopes; Radionuclide Imaging; Sarcoma, Experimental; Serum Albumin, Radio-Iodinated; Technetium; Tin; Ytterbium
PubMed: 46273
DOI: No ID Found