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PubMed1983

Microwave diathermy: effects on experimental muscle hematoma resolution.

The resolution of a muscular hematoma is an important step in the recovery from a muscle injury. Because heat application has been advocated to accelerate this resolution, the effectiveness of microwave diathermy as a means of selectively heating the musculature was studied. For this purpose muscular hematomas were formed in 6 pigs by bilateral injections of blood labeled with the radioisotope chromium-51 (Cr51) into the biceps femoris muscle. One hematoma site was heated with microwave diathermy and the opposite side served as a control. The tissue temperature at the hematoma site was shown to be in the therapeutic range of 42 to 45C, which would cause a maximal local blood flow response. A decay curve was formed by counting the radioactivity of the hematoma site with a scintillation counter. Best fit lines fitted to the decay curves to determine effective half-life values showed that the treated side had a significantly shorter washout time than the control side. This result supports the use of heat as an adjunct to other therapy aimed at resolution of muscular hematomas.

Animals↗
PubMed1980

Effects of local anesthetics on aerobic and anaerobic metabolism of the dental pulp.

Pulps from rat incisor have been dissected out and the respiratory activity in the tissues has been measured in a Gilson respirometer (modified Warburg technique). Local anesthetics lidocain (xylocain) and prilocain (citanest) in concentrations 2.5%, 5%, and 10% have been added to the medium. Effects on the membrane permeability i.e. on the potassium-sodium pump has been studied using incubation at 37 degrees C in 24NaCl. The influx of 24Na has been registered in a scintillation counter. The anaerobic respiratory activity has been studied determining lactate dehydrogenase activity with a spectrophotometric technique. The results show that the concentrations of local anesthetics in the medium of 5% and 10% caused a significantly lower respiratory activity of the cells in the dental pulp. This was not the case in the concentration 2.5%. The isotope studies show a decreased uptake in all concentrations indicating a depression of the potassium-sodium pump activity. The lactate dehydrogenase activity was significantly lower in all concentrations of local anesthetics.

Aerobiosis↗
PubMed1980

A simplified enzymatic assay for the determination of acetylcholine and choline in discrete structures of rat brain.

Acetylcholine and choline were determined in discrete structures of the rat brain by using a simplified radioenzymatic method. Animals were killed by microwave irradiation. The time for killing was controlled by estimating the activity of acetylcholine esterase. After extracting acetylcholine and choline from the tissue by formic acid/acetone the amines were separated by thin-layer-chromatography and radioenzymatically labelled as described by SAELENS et al. The radiolabelled acetylcholine was extracted by sodium tetraphenylboron/hexanone. After washing the organic phase with buffer the radiolabelled acetylcholine was measured in a liquid scintillation counter. The contents of acetylcholine and choline were determined in nucleus accumbens septi, olfactory tubercle and striatum and compared with literature data.

Acetylcholine↗
PubMed1982

A microtechnique for studying chemiluminescence response of phagocytes using whole blood and its application to the evaluation of phagocytes in pregnancy.

Previous investigators have demonstrated that polymorphonuclear neutrophils exhibit intense chemiluminescence (CL) during phagocytosis and the CL response can be used to study the cellular and humoral aspects of the phagocytic process. A microtechnique that used 10 microliters of whole blood as a source of phagocytes was developed and used to measure the phagocytic CL response during pregnancy. Increased sensitivity was achieved by the use of a high concentration of luminol (0.5 mM), prepared by sonication, as a CL amplifier. The high intensity of CL produced with luminol permitted the use of a scintillation counter in the IN coincidence mode, avoiding the necessity of dark-adapting the counting vials and reagents and working under subdued red light. The CL response was dose dependent on the number of phagocytes and/or particles (polystyrene spherules, opsonized zymosan, and E coli). The CL response was decreased by inhibitors that prevent particle uptake (iodoacetate and fluoride), inhibitors that prevent free-radical production (sodium benzoate and superoxide dismutase), and by inhibitors that inactivate myeloperoxidase (cyanide and azide). Results suggested that the phagocytic CL response in our assay system was dependent on O2 activation followed by the activated O2 species reacting with myeloperoxidase and chloride. The new technique was used to demonstrate a progressive increase with gestation in the phagocytic CL response in pregnancy and a rapid decrease to normal values at 1 week postpartum.

Female↗
PubMed1982

[Evaluation of 201Tl-accumulation in lung--imaging of 201Tl in the extravascular space (author's transl)].

In order to evaluate 201Tl-accumulation in lung, 201Tl imaging was performed using a scintillation camera coupling to a small digital computer, and blood clearance of it was examined. After the injection of 74 MBq(2mCi) of 201Tl-chloride, the serial images and static images were obtained. In order to obtain the image of 201Tl in the extravascular space [TE(x, y)], a subtraction technique was performed as follows; after 2 anterior views of 201Tl were obtained using a 20% window centered at 80 keV [T0(x, y)] and 140 keV [T140(x, y)] respectively, and blood sample was taken, radionuclide angiocardiography with 185 MBq (5 mCi) of 99mTc-human serum albumin and it's static image were done in the same supine position and blood sample was taken too. The radioactivity of 201Tl(T) and 99mTc(HB) in the blood was counted by a autogamma scintillation counter. Then the image of TE(x, y) was obtained by the following formula; TE(x, y)=T0(x, y)-[H(x, y)-T140(x, y)]TB/HB. Following results were obtained; (1) The disappearance of 201Tl from the blood was rapid and 15 min after the injection only 10 approximately 15% of the activity after 1 min was present in the blood. (2) The lung activity in the time activity curve decreased rapidly to reach plateau within 100 approximately 150 sec after the injection. (3) The image of 201Tl in the extravascular space was nearly equal to the original one as regard to the radioactivity of 201Tl in lung.

Adult↗
PubMed1982

[Diagnostic value of radioisotope cisternography combined with intranasal pledgets in CSF rhinorrhea].

The experience with the radioisotope cisternography in 17 cases without CSF rhinorrhea for control study and one with CSF rhinorrhea at Tokyo Medical and Dental University Hospital is reported. In addition to the usual cisternography, we used intranasal pledgets for identification and localization of CSF rhinorrhea. The cotton pledgets are placed in the following regions; 1) sphenoethmoid recess, 2) middle meatus and 3) cribriform region. The radioisotope (111In-DTPA, 1mCi) is introduced by lumbar puncture. After scintiphoto is taken at 4 hours, the pledgets are removed and the radioactivity are counted by well-type scintillation counter. The radioactivity of 1 ml of blood is also counted. There is close correlation between the radioactivity of nasal pledget and blood. The ratio of radioactivity of a pledget to that of blood was less than 0.3. The ratio of radioactivity in patient with CSF rhinorrhea is much greater than 0.3. The usefulness of these combined method for identifying the fistulous tract so that surgeon can carry out a direct operation is emphasized.

Adult↗
PubMed1982

[Prospects for conservative treatment of chronic subdural hematomas - investigation of the absorption process].

The most common treatment of chronic subdural hematomas is evacuation and irrigation via burr holes. The theory is that chronic subdural hematomas will undergo a natural healing process if such surgery is performed. However, there is no information concerning the course of hematoma absorption. In this work, 111In-DTPA was injected into the hematoma cavity before and after hematoma evacuation and irrigation in 12 cases of chronic subdural hematoma with comparatively mild symptoms. The radioactivity in the head was measure with time using a scintillation counter and the attenuation rate was obtained. The values measured hourly were expressed as ratios of the 1st measured value. Because of the properties of 111In-DTPA, this attenuation rate was considered to be the absorption rate of the liquid components of the hematoma. In 8 of the preoperative cases, the average measured values, were 84.8 +/- 12.6% after 3 hours, 77.3 +/- 12.1% after six hours, 34.5 +/- 13.8% after 24 hours and 13.3 +/- 13.5% after 48 hours. In six of the postoperative cases, the values were 70.4 +/- 14.3% after 3 hours, 47.8 +/- 10.8% after 6 hours, 12.4 +/- 6.7% after 24 hours and 3.6 +/- 2.0% after 48 hours. In a comparison between the two, the postoperative cases showed clearly advanced absorption with a significant difference at a risk factor of 0.1% or less in each case. This is because the osmotic pressure is the same for the liquid in the hematoma, the blood and the cerebrospinal fluid and an explanation based on this alone is difficult; it is necessary to consider colloid osmotic pressure. When the radioactivities in the liquid in the hematoma, blood and cerebrospinal fluid were measured, the values for the blood were always higher than those for the cerebrospinal fluid and most of the absorption of the hematoma is considered to originate in the vascular bed in the hematoma cavity (sinusoidal channel layer). Therefore, for the conservative treatment of chronic subdural hematomas, it is necessary to consider methods which promote absorption of the hematoma.

Absorption↗
PubMed1982

Breath tests: principles, problems, and promise.

Breath tests rely on the measurement of gases produced in the intestine, absorbed, and expired in the breath. Carbohydrates, such as lactose and sucrose, can be administered in physiologic doses; if malabsorbed, they will be metabolized to hydrogen by colonic bacteria. Since hydrogen is not produced by human metabolic reactions, a rise in breath hydrogen, as measured by gas chromatography, is evidence of carbohydrate malabsorption. Likewise, a rise in breath hydrogen marks the transit time of nonabsorbable carbohydrates such as lactulose through the small intestine into the colon. Simple end-expiratory interval collection into nonsiliconized vacutainer tubes has made these noninvasive tests quite convenient to perform, but various problems, including changes in stool pH, intestinal motility, or metabolic rate, may influence results. Another group of breath tests uses substrates labeled with radioactive or stable isotopes of carbon. Labeled fat substrates such as trioctanoin, tripalmitin, and triolein do not produce the expected rise in labeled breath CO2 if there is fat malabsorption. Bile acid malabsorption and small intestinal bacterial overgrowth can be measured with labeled cholylglycine or cholyltaurine. Labeled drugs such as aminopyrine, methacetin, and phenacetin can be used as an indication of drug metabolism and liver function. Radioactive substrates have been used to trace metabolic pathways and can be measured by scintillation counters. The availability of nonradioactive stable isotopes has made these ideal for use in children and pregnant women, but the cost of substrates and the mass spectrometers to measure them has so far limited their use to research centers. It is hoped that new techniques of processing and measurement will allow further realization of the exciting potential breath analysis has in a growing list of clinical applications.

Bile Acids and Salts↗
PubMed1982

[Sensitivity test of antitumor drugs by the use of isotope].

A sensitivity test of antitumor drugs using primary shortterm culture with 3H-thymidine was performed on stomach cancer patients. Stomach cancer tissues, which were removed in the operating room, were cut into cubes of 1 to 2 mm. Thereafter, they were put on a stainless steel mesh which was placed in a small petri dish (40 X 15 mm) and they were moisted with the cultivating medium. An appropriate dose of antitumor drugs (MM-C, 5-FU, cytosine arabinoside) was added at the onset of cultivation and 3H-thymidine was further added 24 hours later. At the end of cultivation in a CO2 incubator for about 3 days, the specimens were homogenized in an ice-cold homogenizer with 5% trichloroacetic acid. DNA fraction of the specimens was extracted by Schmidt-Thannhauser method. The isotope activity in DNA fraction was measured in a scintillation counter and was represented as cpm/microgram DNA. Sensitivities of antitumor drugs can be determined by comparison between isotope incorporations into the specimens tested and those into control specimens. Bacterial and fungal contaminations were observed in primary stomach cancer tissues.

Antineoplastic Agents↗
PubMed1981

Simultaneous measurement of estrogen and progesterone receptors in tumor cytosols with use of 125I-labeled estradiol and of 3H-R5020.

We describe a dual-isotope assay for measuring the concentration of estrogen receptors and progesterone receptors in tumor cytosols. The concentrations of these receptors are derived from separate Scatchard-plot analyses of a single dextran-coated charcoal assay that incorporates both radioiodinated estradiol and tritiated R5020 as the labeled ligands. The two isotopes, radioiodine and tritium, are easily measured with a liquid-scintillation counter. The concentrations of estrogen and progesterone receptors derived from the dual-label assay are identical to values derived from the respective single-label assays. Moreover, values obtained from an assay with dextran-coated charcoal that incorporates radioiodinated estradiol are identical to those obtained from an assay in which tritiated estradiol is used as the labeled ligand. The dual-isotope assay requires both less time and less tissue.

Breast Neoplasms↗
PubMed1978

An enzymatic radioassay for gentamicin.

An enzymatic, radiochemical assay procedure for measuring serum gentamicin by use of gentamicin 3-acetyl-transferase and [acetyl-14C]acetyl-Coenzyme A is described and evaluated. The enzyme stoichiometrically and quantitatively transfers a radioactive label to the analyte during a 10-min incubation at 37 degrees C. The labeled gentamicin is then absorbed onto phosphocellulose paper discs, which are washed to remove unreacted [acetyl-14C]-acetyl-Coenzyme A and counted in a liquid scintillation counter for 1 min each. The assay detects gentamicin in concentrations as low as 0.2 mg/liter and gives a linear response to concentrations as high as 20 mg/liter. Sisomicin, a structural analog of gentamicin, is measured by the procedure, and tobramycin and netilmicin are slightly reactive. No other interferents were found among other aminoglycosides, other antibiotics, or substances endogenous to serum. Results by the new method are compared to those by radioimmunoassay and a microbiological method.

Acetyl Coenzyme A↗
PubMed1980

Use of limitations of radiolabeled anti-CEA antibodies and their fragments for photoscanning detection of human colorectal carcinomas.

Fifty-three patients with histologically proven carcinoma were injected with highly purified [131I]-labeled goat antibodies or fragments of antibodies against carcinoembryonic antigen (CEA). Each patient was tested by external photoscanning 4, 24, 36 and 48 h after injection. In 22 patients (16 of 38 injected with intact antibodies, 5 of 13 with F(ab')2 fragments and 1 of 2 with Fab' fragments), an increased concentration of 131I radioactivity corresponding to the previously known tumor location was detected by photoscanning 36-48 h after injection. Blood pool and secreted radioactivity was determined in all patients by injecting 15 min before scanning, [99mTc]-labeled normal serum albumin and free 99mTc04-. The computerized subtraction of 99mTc from 131I radioactivity enhanced the definition of tumor localization in the 22 positive patients. However, in spite of the computerized subtraction, interpretation of the scans remained doubtful for 12 patients and was entirely negative for 19 additional patients. In order to provide a more objective evaluation for the specificity of the tumor localization of antibodies, 14 patients scheduled for tumor resection were injected simultaneously with [131I]-labeled antibodies or fragments and with [125I]-labeled normal goat IgG or fragments. After surgery, the radioactivity of the two isotopes present either in tumor or adjacent normal tissues was measured in a dual channel scintillation counter. The results showed that the antibodies or their fragments were 2-4 times more concentrated in the tumor than in the normal tissues. In addition, it was shown that the injected antibodies formed immune complexes with circulating CEA and that the amount of immune complexes detectable in serum was roughly proportional to the level of circulating CEA.

Animals↗
PubMed1981

Technical problems associated with the production of technetium Tc 99m tin(II) pyrophosphate kits.

The amount of tin(II) required for adequate reduction, complexation, and stability of technetium Tc 99m pertechnetate in radiopharmaceutical kits, and methods of preventing the loss of tin(II) during formulation of these lyophilized kits are investigated. Tin(II) loss from stannous chloride solutions was studied under several conditions, including room air versus nitrogen atmospheres, during vial filling in a laminar-flow hood with samples frozen on dry ice versus samples at room temperature, during lyophilization, and during storage under refrigerated, ambient, and elevated temperatures. Various amounts of stannous chloride, ranging from 5 to 1000 microgram/ml, were used in formulating sodium pertechnetate Tc 99m kits containing 100 mCi technetium Tc 99m and 0.4 microgram total technetium. Samples were removed at various times; hydrolyzed technetium, pertechnetate, and technetium Tc 99m pyrophosphate were isolated on instant thin-layer chromatography-silica gel and quantified with a scintillation counter. The time necessary to deoxygenate distilled water by nitrogen purging was measured. Several sources of stannous chloride were assayed for tin(II) content. Tin(II) loss occurs rapidly in solution (15% in one hour) unless continuously protected with nitrogen, and during vial filling in a laminar-flow hood unless frozen with dry ice. No substantial loss of tin(II) was detected during lyophilization or during storage of lyophilized product at any of the three temperatures. A minimum of 400 microgram tin(II) was required to provide 90% technetium Tc 99m pyrophosphate at six hours after preparation. Adequate deoxygenation of small quantities (450 ml) of water was accomplished in less than one hour. Some stannous chloride salts were highly oxidized in the dry state, and only high-purity elemental tin wire gave acceptable yields of tin(II).

Chemistry, Pharmaceutical↗
PubMed1980

The measurement of opsonic and phagocytic function by Luminol-dependent chemiluminescence.

Luminol-dependent chemiluminescence produced by peripheral blood phagocytic cells was measured using a light detecting instrument, the Luminometer 1250 (LKB Wallac). Although less sensitive than liquid scintillation counters, the Luminometer can measure chemiluminescence effectively and detect experimentally induced and clinical variations using small numbers of cells. It is small, inexpensive, simple to use and allows temperature within the reaction vial to be controlled accurately. Light emission can be recorded either graphically or by an intergrated digital printout. Luminol-dependent chemiluminescence is influenced by the presence of contaminating red blood cells and by composition of the medium, particularly presence of phenol red. HEPES buffer and foetal calf serum. Whereas clinical comparisons of opsonic activity are easily performed, comparisons of cellular activity require a high and uniform standard of cell preparation, characterization and maintenance.

Erythrocytes↗
PubMed1980

[Effect of various kinds of glucocorticoids on experimental brain edema (author's transl)].

Although the effectiveness of glucocorticoids for the treatment of cerebral edema has been widely accepted in neurosurgical practice, but its mechanism is still obscure. Also the dose equivalent of various kinds of glucocorticoid preparation is still uncertain. Only the dose equivalent determined by the test examining an antiinflammatory effect on a growth of glanulation, has been applied for the treatment of brain edema. The authors attempted to establish the dose equivalent of each kinds of glucocorticoid for the treatment of cerebral edema. Cold induced cerebral edema was produced by touching a metal probe at the temperature of -90 degrees C for 3 minutes on the right parietal cortex of rat brain. Hydrocortisone (16 mg/kg), prednisolone (3.2 mg/kg), methylprednisolone (3.2 mg/kg), dexamethasone (0.8 mg/kg) and betamethasone (0.8 mg/kg) were administered at the time of 3 hours prior or after the cold injury. The animals were sacrificed 24 hours after injury and the grade of brain edema was determined by the changes of water content in the brain tissue. For this purpose, the authors developed a new method of measuring water content in the brain tissue using tritiated water and a liquid scintillation counter. In the group of animals which were treated with prednisolone, dexamethasone or betamethasone, the water content was significantly decreased compared to the value of non-treated animals. But in the animals treated with hydrocortisone or methylprednisolone, no significant changes of the water content was observed. But in the animals treated with double doses of hydrocortisone (32 mg/kg) or methylprednisolone (6.4 mg/kg), cerebral edema was improved significantly. From these results the authors concluded that the dose equivalent of each kinds of glucocorticoid for the treatment of the brain edema was as follows: hydrocortisone: prednisolone: methylprednisolone: dexamethasone: betamethasone = 40 : 4 : 8 : 1 : 1.

Animals↗
PubMed1980

The use of radioisotopes to measure regional lung water.

A new technique for measuring regional lung water is described. The technique involves single-breath inhalation of C15O2 and 11CO2, with monitoring by external scintillation counters of lung clearance during breathhold. Preliminary studies in anaesthetised dogs and in isolated dog lungs, which validade the technique, are briefly presented. The results show a good correlation with directly measured lung water in non-oedematous lungs, but a tendence to overestimate lung water in the presence of oedema. The potential value of this non-invasive technique for sensitively detecting early pulmonary oedema in man is discussed.

Animals↗
PubMed1978

[A 3H-thymidine paper strip method for stimulation of lymphocytes. I. Culture conditions for human or murine lymphocytes and reproducibility of the paper strip method].

A simple method for stimulation of human or murine lymphocytes is described. As a possible more rapid test than the standard estimation of [3H]-thymidine uptake after solubilisation of cell sediments, paper strip counting in a liquid scintillation counter was studied in 80 individuals and 20 mice. Counting efficiency approaches 1%, the reproducibility is good within the acceptable 16% range.

Animals↗
PubMed1993

Retroviral reverse transcriptase inhibitory activity in Thai herbs and spices: screening with Moloney murine leukemia viral enzyme.

Fifty-seven Thai herbs and spices were examined for their retroviral reverse transcriptase inhibitory activity. All herbs and spices were extracted with hot-water and methanol. Reverse transcriptase inhibitory activity of the extracts was determined by using Moloney Murine Leukemia Virus reverse transcriptase (M-MuLV-RT) reacted with 3H-dTTP and radioactivity measured with a scintillation counter. Eighty-one per cent (46/57) of hot-water extracts and 54% (31/57) of methanol extracts showed inhibitory activities. At a concentration of 125 micrograms/ml, 13% (6/46) of hot-water extracts, namely Eugenia caryophyllus Bullock et Harrison, Phyllanthus urinaria Linn., Terminalia belerica Roxb., Nelumbo nucifera Gaertn., Psidium guajava Linn. and Lawsonia inermis Linn., had a relative inhibitory ratio (IR) over 50%. They showed ratios of 100%, 91%, 75%, 74%, 61% and 60%, respectively. For methanol extracts, only 10% (3/31) had IR values over 50%. They were T. belerica, E. caryophyllus and N. nucifera which exhibited IR values of 83%, 54% and 54%, respectively.

Animals↗