Physics with NOvA: a half-time review

SummaryA study of the removal of I131-labeled Congo red from the blood of amyloid, non-amyloid, multiple myeloma, rheumatoid arthritis and other patients is presented. The percentage removal of the labeled dye shows the same variation reported by many other workers using Bennhold’s test and its modifications.However, there seems to be a positive correlation between the percentage removal of the labeled dye and the presence of amyloid as revealed by biopsy and autopsy. The half-time of disappearance is also correlated with the amyloidosis.The availability of the I131-labeled dye permits the use of very small weights of the dye thereby drastically reducing the possibility of toxic and sometimes fatal reactions encountered with the unlabeled dye. The I131 present permits easy quantitation of the dye in the blood without separation of plasma and obviates the need of fasting. It also permits external counting and scanning of deposits in the organs containing the dye.The availability and use of the labeled dye may stimulate more comparative studies of the removal of the dye from the blood correlated with biopsy and autopsy findings.

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Basic Studies of Various 99mTc-Labelled Renal Agents and Clinical Application of 99mTc-Malate

Nuklearmedizin ◽

10.1055/s-0037-1620604 ◽

1977 ◽

Vol 16 (01) ◽

pp. 36-41 ◽

Cited By ~ 1

Author(s):

T. Machida ◽

M. Miki ◽

M. Ueda ◽

A. Tanaka ◽

I. Ikeda

Keyword(s):

Excretion Rate ◽

Animal Experiments ◽

Imaging Agents ◽

Half Time ◽

Clinical Experiences ◽

Labelling Efficiency ◽

Urinary Excretion Rate ◽

Renal Imaging ◽

The Past ◽

Basic Studies

SummaryVarious renal imaging agents that were reported in the past and a new agent, 99mTc-malate as well as 99mTc-cystein acetazolamide complex were prepared using electrolysis and electrochemical methods. These were studied for their labelling efficiency. After animal experiments with selected 99mTc-com- pounds, 99mTc-rnalate proved to be sufficient for renal imaging with adequate concentration. 99mTcmalate differs from other renal imaging agents in the utilization of endogeneous metabolic product.The first half time of 99mTc-malate in humans is 17 minutes, on the average, and the urinary excretion rate of 99mTc-malate is 36±6.05% in 1 hour after intravenous administration, 44 ± 3.41% in 2 hours and 50 + 5.62% in 3 hours.In our 40 clinical experiences of 99m-Tc-rnalate, most cases demonstrated quite clear renal images in the serial scintiphotos except cases whose serum creatinines were over 4.5 mg/dl.

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Determination of Myocardial FFA Elimination Rates by Functional Images of Uncorrected Half-Time Values

Nuklearmedizin ◽

10.1055/s-0038-1624257 ◽

1984 ◽

Vol 23 (06) ◽

pp. 277-282 ◽

Cited By ~ 1

Author(s):

A. Van Lingen ◽

G. Westera ◽

M. van ◽

W. Den Hollander ◽

E. E. Van der Wall ◽

...

Keyword(s):

Coronary Artery ◽

Regions Of Interest ◽

Heptadecanoic Acid ◽

Half Time ◽

Alternative Method ◽

Functional Images ◽

Functional Image ◽

Back Ground ◽

Objective Determination

SummaryThis paper presents an alternative method of demarcating regions of in terest over the myocardium after ad ministration of 123I-heptadecanoic acid to patients with coronary artery disea se. In a matrix of 32 × 32 pixels the elimination rates of the radioactivity, which are not corrected for back ground activity, are visualized per pixel in a functional image. The func tional image showed areas in the myocardium with high values of uncorrected elimination rates. These areas corresponded with the tracer defects on the scintigram. Corrected elimination rates obtained from re gions of interest of functional images were comparable with those of scinti grams. Thus based on functional im ages of uncorrected elimination rates a reliable, objective determination of regions of interest over normal and abnormal myocardium can be made.

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Analysis of Myocardial Time-Activity Curves of 123l-Heptadecanoic Acid II. The Acquisition Time

Nuklearmedizin ◽

10.1055/s-0038-1628898 ◽

1987 ◽

Vol 26 (06) ◽

pp. 248-252 ◽

Cited By ~ 3

Author(s):

M. J. van Eenige ◽

F. C. Visser ◽

A. J. P. Karreman ◽

C. M. B. Duwel ◽

G. Westera ◽

...

Keyword(s):

Standard Deviation ◽

Acquisition Time ◽

Half Time ◽

Constant Ratio ◽

Time Activity ◽

Time Activity Curve ◽

Time Value ◽

Activity Curve ◽

Low Amplitude ◽

Parameter Values

Optimal fitting of a myocardial time-activity curve is accomplished with a monoexponential plus a constant, resulting in three parameters: amplitude and half-time of the monoexponential and the constant. The aim of this study was to estimate the precision of the calculated parameters. The variability of the parameter values as a function of the acquisition time was studied in 11 patients with cardiac complaints. Of the three parameters the half-time value varied most strongly with the acquisition time. An acquisition time of 80 min was needed to keep the standard deviation of the half-time value within ±10%. To estimate the standard deviation of the half-time value as a function of the parameter values, of the noise content of the time-activity curve and of the acquisition time, a model experiment was used. In most cases the SD decreased by 50% if the acquisition time was increased from 60 to 90 min. A low amplitude/constant ratio and a high half-time value result in a high SD of the half-time value. Tables are presented to estimate the SD in a particular case.

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XYLANASE, AN ENVIRONMENTALLY FRIENDLY BLEACHING AGENT FOR PULP AND PAPER: Characterization And Stabilization Study Of Bacillus licheniformis I-5 CRUDE Xylanase

Jurnal Rekayasa Lingkungan ◽

10.29122/jrl.v7i3.1961 ◽

2018 ◽

Vol 7 (3) ◽

Author(s):

Budiasih Wahyuntari., dkk

Keyword(s):

Thermal Stability ◽

Bacillus Licheniformis ◽

Hot Spring ◽

Sodium Dodecyl ◽

Luria Broth ◽

Crude Enzyme ◽

Half Time ◽

Triton X100 ◽

Sds Page ◽

Xylanolytic Enzymes

Isolate I-5 was isolated from Ciseeng hot spring, West Java and was identified as Bacillus licheniformis I-5. The isolate produces extracellular xylanolytic enzymes on Oatspelt containing Luria broth agar medium. Optimal activity of the crude enzyme was Â observed at 50ÂºC and pH 7. The effect of sodium dodecyl sulphate, b-mercaptoethanol and Triton-X100 were observed. Incubating the crude enzyme in 1.5% SDS and 1.5% b-mercaptoethanol at 50oC for 90 minutes then adding Triton-X100 at final concentration of 3.5% for 45 minutes only reduced 5.75% of the initial enzyme activity. SDS/PAGE and zymogram analysis showed that at least two xylanolytic enzymes presence in the crude enzyme. The molecular weight of the enzyme was estimated about 127 and 20kD. The enzyme hydrolysed xylan into xylobiose, xylotriose and other longer xylooligosaccharides. Thermal stability of the crude enzyme was observed at 50, 60, and 70oC and pH 7 and 8. The results showed that the half time of the crude enzyme incubated at 50, 60, and 70oC pH 7 was 2 hours 55 minutes; 2 hours 33 minutes and 1 hour 15 minutes respectively. The half time at 50, 60 and 70oC, pH 8 was 2 hours 48 minutes; 1 hour 22 minutes and 1 hour 9 minutes respectively.keywords: Xilanase, Bacillus licheniformis I-5, thermal stability

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Hepatic uptake of intact glutathione S-conjugate, inhibition by organic anions, and sinusoidal catabolism

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1993.265.3.g547 ◽

1993 ◽

Vol 265 (3) ◽

pp. G547-G554

Author(s):

C. A. Hinchman ◽

A. T. Truong ◽

N. Ballatori

Keyword(s):

Guinea Pig ◽

Rat Liver ◽

Marked Decrease ◽

Hepatic Uptake ◽

Half Time ◽

High Concentrations ◽

Rat Livers ◽

Dose Dependent ◽

Uptake And Metabolism ◽

Guinea Pig Liver

To identify potential mechanisms for hepatic removal of circulating glutathione (GSH) conjugates, uptake and metabolism of S-2,4-dinitrophenylglutathione (DNP-SG) were examined in isolated perfused livers from rat and guinea pig. Guinea pig livers perfused with 5 mumol of DNP-SG in a recirculating system (50 microM initial concn) rapidly cleared the conjugate from the perfusate (half time 3.7 min), whereas clearance was considerably slower in rat liver (half time 35 min). Disappearance of DNP-SG from the perfusate was accompanied by a simultaneous appearance of DNP-SG and its metabolites in bile. Addition of acivicin, an inhibitor of gamma-glutamyltransferase (gamma-GT), to the perfusate resulted in a marked decrease in DNP-SG clearance by guinea pig liver but had no effect in rat liver, suggesting that in the guinea pig this process is largely dependent on sinusoidal gamma-GT activity. However, even in the presence of acivicin, rat and guinea pig livers removed nearly one-half of the administered DNP-SG from the recirculating perfusate over 30 min. High concentrations of DNP-SG were found in bile (up to 3.7 mM), indicating that the liver is capable of transporting the intact conjugate from the circulation. When rat livers were perfused with higher concentrations of DNP-SG (100 and 250 microM), biliary excretion of DNP-SG increased dose dependently, with concentrations in bile reaching 10 mM at the higher dose. This was accompanied by a dose-dependent choleresis.(ABSTRACT TRUNCATED AT 250 WORDS)

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O2 transfer kinetics in a whole blood unicellular thin layer

Journal of Applied Physiology ◽

10.1152/jappl.1990.68.5.1854 ◽

1990 ◽

Vol 68 (5) ◽

pp. 1854-1864 ◽

Cited By ~ 13

Author(s):

E. Heidelberger ◽

R. B. Reeves

Keyword(s):

Thin Layer ◽

Fiber Optics ◽

Whole Blood ◽

Gas Flow ◽

Release Kinetics ◽

Gas Diffusion ◽

Attractive Alternative ◽

Half Time ◽

O2 Uptake ◽

Mixing Techniques

A planar monocellular layer of whole blood (WB) sandwiched between two Gore-Tex membranes is used to study O2 uptake and release kinetics at 37 degrees C. Gore-Tex, a highly gas-permeable open mesh of Teflon fibrils (78% porosity, 0.2-microns pore size, 75-microns thick), constrains WB to form a thin film without imposing an appreciable gas diffusion barrier. WB layer thickness, measured by isotope dilution, is 1.7 +/- 0.2 microns. WB films are mounted between fiber optics in a gas flow tube for dual-wavelength (536/558 nm) oxyhemoglobin saturation measurements after a step change in PO2. For isocapnic (6% CO2) step changes in PO2 between 0 and 104 Torr, WB O2 uptake half time is 10.4 +/- 0.9 ms; WB O2 release half time is 20.6 +/- 2.4 ms. Half-time values are half of those previously reported. The thin-layer method reduces erythrocyte diffusion boundary layer error and thereby offers an attractive alternative to classical rapid fluid-mixing techniques.

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