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PubMed1990

[Changes in the content of neuromediator amino acids in the brain of mice with a convulsive syndrome induced by the hyperactivation of CNS cholinergic structures].

Methods of thin-layer chromatography with the following elution and photometry were used to determine the amount of taurin, glycin and glutamate in mouse brain 20 and 60 min after injections of arecolin (10 mg/kg), nicotin (9 mg/kg), fluorostigmin (3 mg/kg) and picrotoxin (8 mg/kg). It was determined that seizures induced by these drugs are followed by raising of the levels of taurin (on 20-70%), glycin (after 60 min on 30-70%), glutamate (after 20 min--on 70-60%). The level of glutamate was lowered (by 40-80%) to 60 min after injections of nicotin, fluorostigmin and picrotoxin.

Amino Acids↗
PubMed1977

[Quantitative histoenzymologic characteristics of the human submandibular salivary glands].

Quantitative activity of oxidative-reductive and hydrolytic enzymes obtained during operation was investigated in different parts of the human submandibular salivary glands. Quantitative estimation of enzymic activity was done by photometry of the negatives prepared on MY-phi-6. Comparative examination of enzymatic activity made it possible to state that according to the peculiarities of metabolic processes, the cells of striated and intralobular secreting ducts are similar to the cells of the secreting terminal parts. A high activity of NADP-diaphorase, G-6-PhDG and acid phosphatase in the epithelium of the secreting ducts, and parallelism, stated between histoenzymatic and morphologic criteria of functional activity proved the participation of these structural-functional units in secret-producing processes. A high activity of NAK-diaphorase, LDG and acid phosphatase in all the parts and in the secreting ducts system, in particular, ensures, besides the processes of protein secret formation, an active transport of natrium and potassium, formation of final saliva and its discharge.

Acid Phosphatase↗
PubMed1990

Diurnal variation in water, sodium and potassium excretion in primary glomerulonephritic patients and its relation to diurnal kallikrein excretion.

In order to investigate whether or not primary glomerulonephritic patients have abnormal diurnal water, sodium, and potassium excretion and its relation to diurnal urinary kallikrein excretion (UKE)., we studied the diurnal patterns of urinary water, sodium, potassium, and kallikrein excretion in 16 primary glomerulonephritic patients and 12 normal persons. Urinary kallikrein activity was measured by the enzymatic hydrolysis of synthetic chromogenic substrate S-2266, and urinary electrolytes were measured by flame photometry. The day, night, and 24-hour urine outputs were significantly higher in glomerulonephritic patients, but urinary sodium, potassium and kallikrein excretion at all periods of collection did not differ between glomerulonephritic patients and normal controls. UKE was positively correlated with urinary potassium excretion in both normal controls (r = 0.5, p less than 0.05) and glomerulonephritic patients (r = 0.66, p less than 0.01), whereas no correlation existed between UKE and urinary water excretion, or UKE and urinary sodium excretion in either group. The day/night output ratio of water, sodium and potassium excretion were not different between glomerulonephritic patients and normal subjects. These results indicate that: (1) there is no abnormal diurnal water, sodium, potassium, and kallikrein excretion in primary glomerulonephritic patients with fair renal function; and (2) urinary kallikrein may play a role in the regulation of urinary potassium excretion.

Adult↗
PubMed1991

Population pharmacokinetics of lithium.

The population pharmacokinetics of lithium was determined. Psychiatric inpatients who were at least 18 years old, had normal renal function, and were receiving lithium two or three times daily were the subjects of the study; 79 patients met the criteria. Serum lithium concentrations were measured by flame photometry 12 hours after the evening dose. Other data collected included age, gender, race, height, weight, serum creatinine and sodium concentrations, diet, and concurrent drug use. The nonlinear mixed-effects model (NONMEM) program was used to estimate lithium clearance, lithium volume of distribution, and error variability and to determine the influence of patient characteristics on lithium clearance. With the initial model, the mean lithium volume of distribution was 32.8 L and mean lithium clearance was 1.36 L/hr. With an intermediate model, lithium clearance estimates improved on the basis of patient size (weight and body surface area), daily lithium dosage, age, gender, and race. When only the most significant variables--lean body weight and creatinine clearance--were retained, a final model was obtained that yielded a coefficient of variation for lithium clearance of about 24% and gave fairly accurate predictions of steady-state lithium concentrations (coefficient of variation, about 16%). Analysis of lithium pharmacokinetics with the NONMEM program suggested that lean body weight and creatinine clearance are important predictors of lithium clearance.

Adolescent↗
PubMed1990

A fluorometric viability assay for single human and rat islets.

A microfluorometric viability assay for isolated human and rat islets of Langerhans has been developed using the fluorochromes fluorescein diacetate and propidium iodide. Fluorescein diacetate causes live cells to fluoresce green under blue light excitation (490 nm); propidium iodide causes dead cells to fluoresce red under green light excitation (454 nm). The fluorescence intensity from the live and dead cells within a single islet was selectively measured by photometry using 520 nm and 610 nm barrier filters with blue and green light excitation respectively. All measurements were corrected for background fluorescence. The proportion of dead cells within single human or rat islets measured by microfluorometry was found to correlate highly significantly (r = 0.99, P less than 0.001) with the proportion of dead cells measured by dissociating the same islet into a single cell suspension and counting the actual proportion of dead cells. This assay therefore provides a rapid, accurate and objective measurement of the proportion of dead cells within isolated human and rat islets.

Animals↗
PubMed1990

Video fluorescence microscopy as a tool for the study of cellular heterogeneity in epithelia.

The use of functional fluorescent dyes has allowed us to monitor intracellular pH in individually identified cells in renal epithelia. Using video microscopy we simultaneously measured the change in intracellular pH in several contiguous cells in response to various maneuvers. The video equipment included a silicon intensified target camera, a VHS videocassette recorder, a high resolution monochrome monitor, a video photometric analyzer and a 2-channel chart recorder. This equipment had a spatial resolution of 1 micron by light microscopy and a response time of less than 200 ms; it allowed us to perform double fluorescent labeling and obtain reliable measurements of intracellular pH, independent of gain, regardless of the location of the image on the screen. Using this video system we have shown that there is substantial heterogeneity in activity of H+/HCO3- transport pathways among adjacent cells in a monolayer of cells cultured from the rat renal inner medullary collecting duct. In isolated perfused rabbit renal cortical collecting ducts, video microscopy allowed us to show that there are two different types of intercalated cells: one that exhibits apical Cl-/HCO3- exchange and one that does not. Both show alkaline intracellular pH with respect to non-acid-base transporting epithelia. Video microscopy has several advantages over conventional microspectrophotometry. It provides rapid data acquisition along with increased sensitivity and the capacity for some subcellular analyses. One is able to analyze several individually identified cells during an experimental maneuver. The present video system was assembled for less than $15,000 and permits a more complete analysis of an epithelium than either single-cell photometry or spectrophotometric analysis of thousands of cells in suspension or monolayers.

Animals↗
PubMed1990

[Participation of agonists and antagonist of opiate receptors in the regulation of contractile activity of lymphatic microvessels of the rat mesentery].

The contractile activity of the wall and valve of lymphatic microvessels (LM) of the rat mesentery were studied biomicroscopically by optic photometry. Opioid peptides-Leu-enkephalin and dalargin-stimulated LM. Preliminary application of naloxone on the LM prevented the appearance of the LM contractions following the Leu-enkephalin-application. Naloxone did not inhibit contractions of LM previously activated by Leu-enkephalin. It is supposed that opioid mechanisms are involved in the regulation of the LM contractile activity.

Animals↗
PubMed1990

[Kininase II (SACE) and renin in sarcoidosis patients and healthy probands in exercise testing].

Over a period of three years, we investigated the behaviour of renin and kininase II in 26 patients with active, histologically confirmed sarcoidosis in comparison with healthy test subjects, during ergometer exercise. Renin activity was determined radioimmunologically, and kininase II by means of spectral photometry (Cushman-Lieberman method). In both groups, a significant increase in renin and kininase II during the course of exercise on the ergometer was observed, which, however, was more marked in the sarcoidosis group of patients. Furthermore, the activities of both enzymes were highly significantly elevated as compared with the group of healthy subjects in each individual phase of exercise. In addition--if we consider the average values of the two enzymes in each of the individual subjects--it would seem possible in most cases to correctly ascribe the person involved to the group healthy subjects or patients, in particular when the average values of renin and kininase II obtained as described above, are multiplied together.

Exercise Test↗
PubMedDate not supplied

[The use of photographic materials as a dry reagent for determining the peroxidase activity of biological preparations].

A new method is reviewed for measuring the peroxidase activity of biopreparations using light quantum-sensitized photographic material as a detector. The method involves the combination of the reactions of peroxidase oxidation of hydroquinone, a constituent part of the developing solutions, by hydrogen peroxide and photochemical interaction of the remaining hydroquinone with silver halogenides of the photoemulsion layer. Visually, up to 2 ng/ml of horse radish peroxidase is detectable. On photometry of the spots obtained, the limit of peroxidase demonstration amounts to 0.6 ng/ml. The data obtained during measurements of the peroxidase activity of the saliva, blood serum, plant extracts and immunoenzymic conjugates are provided.

Humans↗
PubMed1990

[Metabolism of potassium in the acute phase of myocardial infarction].

The aim of the study was to evaluate changes in potassium level at 1 to 4 days in patients with acute myocardial infarction. The studies comprised 103 patients including 85 men and 18 women, aged from 31 to 90 years (mean age 56.7 +/- 11.7). A control group consisted of 51 patients (40 men, 11 women) aged from 34 to 74 years (mean = 56.7 +/- 10.7) on intensive diuretic therapy due to heart failure without myocardial infarction. In order to establish our own normal limits of potassium level in the blood serum and erythrocytes 20 healthy subjects (10 men, 10 women) aged 34 to 54 years (mean = 37.8 +/- 9.1) were studied. In patients with acute myocardial infarction and in control subjects serum potassium levels (Ks), erythrocyte potassium content (Ke) and urine potassium level (Ku) had been determined. Serum and erythrocyte potassium levels were assessed by Mayer method with the use of flame photometer. Urine potassium level was also determined by flame photometry. Values of serum and erythrocyte potassium level were given in mmol/l, and urine potassium levels in mmol/h. Ks, Ke and Ku values at 1 to 4 days were compared with one other and with levels in the control group and in healthy subjects as well as with values assumed as normal. At 1 day of the myocardial infarction Ks-3.87 +/- 0.58 mmol/l was significantly lower as compared with Ks at 2, 3 and 4 days and with values in the control group: Ks = 4.4 +/- 0.49 mmol/l and in healthy subjects: Ks = 4.2 +/- 0.36 mmol/l (p less than 0.0001). Ke levels at 1 and 2 days were 98.3 +/- 5.6; 99.2 +/- 5.3 mmol/l; significantly lower as compared with the levels at 4 days (Ke = 102.5 +/- 5.8 mmol/l p less than 0.05) and as compared with the levels in the control group: Ke = 104.5 +/- 6.1 mmol/l (p less than 0.05) and in healthy subjects: Ke-102.6 +/- 5.8 mmol/l (p less than 0.01). In contrast Ku level at 1 day of the infarction was 4.6 +/- 3.2 mmol/h and it was significantly higher as compared with excretion levels on the remaining days and in the control group: Ku = 2.7 +/- 0.7 mmol/h (p less than 0.0001). The present studies show changes in the potassium level in the acute phase of the myocardial infarction consisting in a decrease of Ks and Ke levels and an increase in Ku level, mainly at 1 day of the infarction.

Adult↗
PubMed1990

An osmotic gradient in ischemic brain edema.

We studied how the osmotic pressure gradient between blood and the brain is related to the development of ischemic brain edema. Focal cerebral ischemia was produced by left MCA occlusion in rats. Brain osmolality was determined with a vapor pressure osmometer, water content of the brain tissue was measured by wet and dry weight, and the tissue sodium and potassium contents were assayed by flame photometry. Permeability of BBB was tested by EB. These measurements were made from the cortical core of MCA territory at various intervals from 1 hr to 14 days after occlusion. Brain osmolality increased from 311 +/- 2 mOsm/kg (M +/- SE) to 329 +/- 2 mOsm/kg (n = 7, p less than 0.01) by 6 hrs after occlusion. Serum osmolality did not significantly change. The osmotic gradient between blood and the brain was about 26 mOsm/kg. Brain osmolality then decreased to 310 +/- 2 mOsm/kg by 12 hr after occlusion and remained about the same level for up to 14 days. Water content progressively increased within 1 day, then gradually decreased by 14 days. Sodium plus potassium content of the brain tissue did not increase and EB extravasation was not seen within 6 hr of occlusion. These findings indicate that an osmotic pressure gradient contributes to the formation of edema only during the early stage of cerebral ischemia. Brain osmolality is not related to tissue electrolyte change and BBB disruption to protein.

Animals↗
PubMed1986

Differential distribution of cell adhesion molecules during histogenesis of the chick nervous system.

We have compared the expression of the neural cell adhesion molecule (N-CAM) and the neuron-glial cell adhesion molecule (Ng-CAM) during histogenesis of the chick nervous system. Data from immunohistochemistry and photometry were combined to construct maps of the overall distribution and dynamics of CAM appearance and disappearance. Each CAM appeared in a characteristic spatial and temporal pattern in various areas during cell movement, fiber outgrowth, tract formation, and myelination. N-CAM was more uniformly distributed than Ng-CAM and was present on all neural cell bodies and processes of the CNS and PNS. In the adult, the staining pattern of N-CAM remained similar to that in the embryo, although the staining intensity was diminished. During embryonic development, Ng-CAM was expressed on extending neurites and migrating neurons. The appearance Ng-CAM in the CNS was correlated particularly with times of cell migration in spinal cord and cerebellum, and in regions undergoing neurite extension, such as the developing white matter of the spinal cord, the optic nerve, and the medial longitudinal fasciculus. Cell bodies not undergoing migration were negative for Ng-CAM. In the adult CNS, Ng-CAM was markedly decreased in myelinated fiber tracts like the white matter of the spinal cord but persisted in unmyelinated regions such as the olfactory bulb. In contrast, in the PNS (for example, the dorsal root ganglion and sciatic nerve), Ng-CAM appeared early on both cell bodies and neurites, and it continued to be present on both in the adult, even in the presence of myelin. Maps comparing the relative distribution of Ng-CAM and N-CAM showed dynamic reversals as the nervous system developed and, as a result, the pattern of CAM expression was markedly different in embryos and adults. This difference appears to reflect changes in the roles of selective adhesion and of the two neuronal CAMs at different times of development.

Animals↗
PubMed1989

Factitiously high sodium activities on the Ektachem 400 owing to interferences by high gamma-globulin concentrations.

Sera from patients with above-normal gamma-globulin concentrations give sodium values as much as 10% higher when measured in the Kodak Ektachem 400 analyzer than results obtained with the Beckman Astra-8 analyzer. Results obtained with the Astra were in agreement with flame photometry. A similar relative bias was observed for potassium measurement in the Ektachem. This discrepancy was corrected when we used a new generation of reference fluid provided by Kodak, which is currently available for general use.

Adult↗
PubMed1989

[A method of determining allergic changes in leukocytes].

The new technique for the detection of hypersensitivity to allergens is based on the fact that after 2 hrs incubation of citrate blood with the allergen the leukocytes are destroyed and K ions leave the cell. Potassium level in the supernatant is measured by flame photometry. This method has been tried in examinations of 81 patients with pulmonary tuberculosis and aspergillosis and 18 healthy donors. The method has proved to be specific and informative for the detection of tuberculin and fungal allergy. It is less labor-consuming than the determination of the neutrophil injury index and more objective, since its results are recorded instrumentally.

Aspergillosis↗
PubMed1989

[A screening method of analysis of middle weight molecules].

Using the screening method, the level of middle-mass molecules was examined in 192 donors and 44 patients with peritonitis. The following factors are essential for the reproducibility of the method and for decreasing the results scatter: (1) use of trichloroacetic acid for optic control and standardization of the preparation of this solution according to optic density; (2) photometry is carried out at a wavelength of 235-240 nm; (3) accurate collection, preparation, and storage of the material; (4) calculation of the indexes of distribution according to 238/260 and 238/280 ratios. Adherence to these recommendations and to some others essentially improves the clinical diagnostic potentialities of the described method for the evaluation of peritonitis severity and of the body intoxication.

Humans↗
PubMed1989

[The use of Soviet substitutes for batroxobin in the determination of fibrinogen].

Plasma fibrinogen was measured by kinetic photometry with two Soviet analogs of the foreign agent batroxobin: ancistron-N and agichal, obtained from Central Asian Aspidelaps lubricus venom by different techniques. Both the preparations of thrombin-like enzyme from the venom have proved to be adequate substituents of batroxobin; the optimal concentration of ancistron-N for this test was found to be 20 micrograms/ml or 0.04 U/ml, that of agichal 0.5 micrograms/ml.

Fibrinogen↗
PubMed1989

Immunotherapy of treated BL/LL cases with BCG: histopathological, immunohistological and bacteriological assessments.

The persistence of dead as well as viable bacteria is an important therapeutic problem in multibacillary leprosy. In highly bacillated patients, viable bacteria are detectable in 10-15% of cases after 2 years of treatment and none of these cases became smear negative by 2 years of recommended multidrug therapy (MTD). Immunotherapy trials using BCG (0.1 mg) by intradermal route have been undertaken in cases who had MDT for 2 years and who had viable bacilli by ATP photometry and/or FDA-EB staining. Biopsies and smears were taken from local as well as distant sites at 0.4 weeks and 6 months after BCG vaccination. Biopsies were processed for ATP counts, FDA-EB staining, histopathology and immunohistology for cell types at 0.4 weeks. There was transient effect on BI, ATP counts, FDA-EB staining at local as well as distant sites in some cases. Histopathology and immunohistological findings suggest that there is tendency to form epithelioid cell granuloma at local site in all cases and at distal sites in some. There was infiltration of subepidermal zone in one case, 4 weeks after vaccination. BCG may be of use as potential immunotherapeutic agent but its usefulness needs to be investigated in depth preferably in the beginning or early phases of chemotherapy and with also repeated inoculations.

BCG Vaccine↗
PubMed1989

Visualization and quantitation of poly A+-mRNA by using in situ hybridization with biotinylated oligonucleotides.

HeLa cells and synovial tissue sections were used for visualizing poly A+-mRNA after in situ hybridization. We describe a method to biotinylate hybridization probes by tailing oligo-dT nucleotides with biotinyl-dUTP using terminal deoxynucleotidyl transferase (E.C.2.7.7.3.1.). The hybrids were detected by using the strepavidin-biotin-peroxidase complex (ABC method). The reaction product of the peroxidase staining in the cells and in the tissue sections, is quantitated by the method of plug- and scanning photometry respectively.

HeLa Cells↗