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PubMed1983

[Measurements of iron, lead, arsenic and selenium concentration in respirable and nonrespirable fractions of Berlin urban aerosols].

In the scope of air quality determinations in the city of Berlin, size fractioned immission concentrations of the heavy metals iron, lead and cadmium and the metalloids arsenic and selenium in suspended particulate matter in air were determined at a highly polluted urban site. The samples were gathered from Juli until December 1981 with a 6-stage-plus-backup high-volume cascade impactor, extracted with 33% HNO3 and analyzed with atomic absorption photometry (AAS) (flame: iron and lead, hydride system: arsenic and selenium) and inductively coupled plasm spectroscopy (ICP) (cadmium). The results show, that - the applied sampling and analyzing procedure proved to be suitable, - the immission concentrations of suspended particulate matter less than 10 micron in Berlin are comparatively high, with values up to 295 ng/m3, - the immission concentrations of the selected trace elements in suspended particulate matter less than 10 micron in Berlin are comparatively low for an industrialized area like this city (Fe: 1280 ng/m3, Pb: 325 ng/m3, Cd: 3.74 ng/m3, As: 11.9 ng/m3, Se: 1.6 ng/m3), but increase markedly during periods of air stagnation as they are quite common in the Berlin winter season (Fe: 2970 ng/m3, Pb: 859 ng/m3, Cd: 8.26 ng/m3, As: 67.3 ng/m3, Se: 6.68 ng/m3), - lead, cadmium, arsenic and selenium of main environmental hygienic interest were concentrated on particles smaller than 2 micron.

Air Pollutants↗
PubMed1984

Photometric oculometry. II. Measurement of axial ocular distances with slit-lamp microscopy. Clinical evaluation, and comparison with ultrasonography.

Photometric oculometry is a slit-lamp technique, which makes possible an estimation of intraocular axial distances and axial length. The technique is based on a transformation of a sagittal slit-lamp movement into intraocular axial distances when the slit-lamp focal plane is moved in the optical axis from retina to cornea. Determination of the axial length in 50 eyes (refractive range +4.75 to -5.25 D) showed that the axial length varied from 21.9 mm in hypermetropic eyes to 26.0 mm in myopic eyes, with the emmetropic eyes being approximately 24 mm. A comparison of intraocular axial distances determined by photometric oculometry and by ultrasonography on a small series of eyes showed no significant differences between the axial length, the length of the vitreous body, and the lens thickness, whereas a significant difference between the anterior chamber depth was observed (photometry giving slightly larger values than ultrasound).

Adult↗
PubMed1984

[Catalase and peroxidase activity of porphyrins].

Using spectroscopic photometry, the catalase-like and peroxidase-like activities of some metal complexes of hematoporphyrins and tetraphenylporphyrins were detected. The rate constant for hydrogen peroxide degradation by porphyrins was determined. The possible mechanism of catalysis is discussed.

Catalase↗
PubMed1984

[Secretion of the salivary glands of the medicinal leech Hirudo medicinalis inhibits ADP-induced aggregation of human platelets and platelet adhesion to a collagen-coated surface].

As was earlier demonstrated, secretion of medical leech exhibits high antithrombin activity of hirudin and inhibits contact activation of factor XII. Attempts were made to investigate the effects of the leech secretion on (i) the ADP-induced aggregation of platelets in suspension, registered by photometry according to Born, and (ii) platelet adhesion to the calf skin collagen-coated surface measured by scanning electron microscopy. The following results were obtained: 1) the secretion at doses of 0.13 vol % and 0.75 vol % inhibits the ADP-induced aggregation of gel-filtered human platelets by 50 and 97%, respectively; 2) the secretion inhibits the total adhesion and initial attachment of the gel-filtered platelets to the collagen substrate by 60-70% (dose 0.1-1.0 vol %) and 87-88% (dose 10 vol %); 3) platelet spreading on the collagen substrate and adhesion of the platelets from suspension to the upper surface of the spread platelets are inhibited by the secretion as well, but these effects are not statistically significant. The data obtained suggest that the secretion contains components which inhibit both the coagulating and platelet-vascular wall pathways of hemostasis.

Adenosine Diphosphate↗
PubMed1982

Purification of human granulocyte-macrophage progenitor cells (CFU-C) using indirect immunofluorescence and cell sorting.

We have attempted to purify human bone marrow granulocyte-macrophage progenitor cells utilizing purified stimulating factor, indirect immunofluorescence and cell sorting. These cells can be labelled by sequential incubation with colony-stimulating factor (CSF), rabbit anti-CSF antibody and fluorescently labelled goat anti-rabbit gamma globulin. Flow photometry demonstrated that binding of CSF to marrow cells varied with CSF concentration and duration of incubation. Marrow cells were pre-concentrated by incubation with carbonyl iron followed by Percoll gradient centrifugation and then labelled by this indirect immunofluorescence method. Sorting of these cells yielded up to 95-fold purification of colony-forming cells and fractions containing in excess of 10% colony- and cluster-forming cells.

Bone Marrow Cells↗
PubMed1982

[Urinary excretion of aldosterone in patients with hypertension].

Plasma value, by dye-dilution method, sodium excretion and potassium quantity in plasma by flame photometry, plasma renin activity by radioimmune method and aldosterone excretion with urine by spectrophotometric method were studied in 34 patients with I, II and III stage of hypertonic disease. Aldosterone excretion was established to be normal in 55.8 of the patients and increased in 44.2 per cent. The excretion of aldosterone showed no discrepancies in the patients with hypertonic disease depending on the size of plasma volume. Aldosterone excretion was increased in hypertonic patients with high plasma renin activity as compared with the subjects with normal and with reduced plasma renin activity. Reverse interrelations were established as regards sodium excretion.

Adult↗
PubMed1982

A quantitative approach to efficiency and sensitivity: enzyme histochemistry, immunofluorescence and PAP-technique in tissue sections.

Aminopeptidase was demonstrated and its concentration measured in the bile canaliculi of frozen pig liver sections. Sections were stained for enzymic activity by conventional histochemical means, by using purified rabbit anti-aminopeptidase followed by fluorescent labelled anti-rabbit-immunoglobulin and rabbit peroxidase anti-peroxidase complex. Absorption and fluorescence measurements by microscopic photometry revealed that under the conditions used the minimal amount of reaction product detectable by the PAP-technique is 3 to 10 times smaller than that of fluorescent stain by immunofluorescence technique, i. e. the PAP-technique is 3 to 10 times more efficient and relative to the amount of detectable anti-aminopeptidase approximately 3 times more sensitive. For the given enzyme concentration in the tissue these two techniques were as sensitive as conventional histochemistry. Saturation of the sites of an antigen within the tissue with antibody is essential for quantitative determination of antigens.

Aminopeptidases↗
PubMed1983

Evaluation of a direct potentiometric method for sodium and potassium used in the Du Pont aca.

We evaluated an accessory that enables the Du Pont aca discrete analyzer to measure Na+ and K+ by direct potentiometry (aca/ISE). Na+ and K+ gave linear responses in both the blood and urine modes, with no carryover. No interfering species were identified in the blood mode. Intra-assay and interassay precision for Na+ and K+ were more than adequate and analytical recoveries comparable to those with flame photometry were found for plasma. The Na+ and K+ values for plasma were comparable with those obtained by use of another direct potentiometric analyzer (the Orion SS-30), but slightly higher than flame-photometric values. Samples from patients with hyperlipemia and multiple myeloma gave clinically relevant values with the aca/ISE, but the flame photometric values were artefactually low. Whole blood could not be accurately analyzed. The aca/ISE is a precise, easy-to-use instrument, which gives values for plasma similar to those obtained with direct potentiometric analyzers. For analysis of urine, certain precautions are necessary.

Autoanalysis↗
PubMed1983

Influence of thyroid hormone on the in vitro translational activity of specific mRNAs in the rat heart.

The influence of thyroid hormone on the translational activity of specific cardiac mRNA was determined by in vitro translation of RNA isolated from the heart of normal, hypothyroid, and 3,3',5-triiodo-L-thyronine-injected hypothyroid rats. Proteins synthesized in vitro in the presence of [35S]methionine were separated by two-dimensional gel electrophoresis and quantitated by a novel scanning procedure using digital matrix photometry. A total of 421 translational products were detected by fluorography and changes in the predominance of 12 of these were influenced by the thyroid state of the animals. The relative predominance of 8 species was increased in euthyroid animals, whereas 4 translational products were increased in hypothyroid animals. The majority of these thyroid hormone-related alterations occurred in spot pairs of similar molecular weights, but slightly different isoelectric points. In contrast, the relative predominance of mRNAs coding for the major contractile proteins, light chain 1, light chain 2, tropomyosin, actin, and myosin heavy chain was not altered by the thyroid status of the animals. The relative levels of these abundant mRNA species remained unaltered in spite of a thyroid hormone-related increase in total RNA levels. In vivo effects of thyroid hormone on cardiac RNA levels are complex. In addition to a general increase in total RNA and mRNA levels, increases or attenuations in the predominance of a small number of specific mRNA species are observed when euthyroid and hypothyroid animals are compared.

Animals↗
PubMed1983

Potentiometry of Na+ in undiluted serum and urine with use of an improved neutral carrier-based solvent polymeric membrane electrode.

We present an improved Na+-selective liquid membrane electrode for measurement of Na+ concentrations in both undiluted serum and urine. The values for urinary Na+ obtained with the ion-selective electrode agree well with those obtained with the flame photometer. The correlation gives a standard residual deviation of +/- 2.7 mmol/L over the Na+ range of 25-280 mmol/L. In serum, this direct potentiometry yields Na+ concentrations 5.4% (SD 1.1%) higher than those obtained by atomic spectrometry and a standard residual deviation of +/- 1.1 mmol/L. Correction of these values for the volumes of protein and lipid leads to potentiometric values 1.2% (SD 0.7%) lower than those by flame photometry (residual standard deviation: +/- 1.0 mmol/L). Other factors that possibly contribute to this discrepancy are discussed.

Electrodes↗
PubMed1983

Correlation between chromatin morphology as derived by digital image analysis and autoradiographic labeling pattern.

In order to interpret the Feulgen-dependent chromatin morphology on a functional basis, we performed model experiments in which labeling with 14C-thymidine and 14C-uridine was used as a functional parameter. Using a relocation facility, information on either DNA or RNA, labeling intensity of a cell was added to the parameters of image analysis by measuring the same cell by scanning photometry after Feulgen staining. The Feulgen-stained nuclei were interactively sampled and automatically segmented. Most of the textural information was gained from a flat texture image obtained by subtracting the original image from a median-filtered image. In addition to the autoradiographic features, visually recognizable differences in nuclear morphology, such as the number of nucleoli and the level of condensed (inactive) and diffuse (active) regions of the chromatin, were also correlated with textural parameters. Using the supervised cluster analysis method, an attempt was made to establish a correlation between visual nuclear morphology and autoradiographic labeling intensity that improved the functional understanding of the Feulgen features. Our results further clarify the supramolecular chromatin structure and its dynamics during specific transitions in the cell cycle, namely the G0-G1, G1-S and S-G2 transitions; this information may become useful in diagnostic procedures.

Animals↗
PubMed1980

[Automatisation in microfluorometry (author's transl)].

The combination of microphotometer systems with different types of computers allows various possibilities of automatisation in fluorescence photometry. This paper presents several examples of automated fluorometry as testing of preparation and staining, determination of fluorescence intensity with instantanous background correction, controlling a scanning system for detection of immunofluorescence on microplates, rapid microspectroscopy of fluorescence emission, quantification of fading phenomena, help for chromosome analysis and also facilities of data correction and statistical data evaluation.

Computers↗
PubMed1980

Antibody to purified human colony-stimulating factor: use in the identification and isolation of granulocyte macrophage progenitor cells.

Conditioned media prepared from human lung, placenta, peripheral leukocytes, cultured human pancreatic carcinoma cells, and cultured cervical carcinoma cells exhibit a common pattern of two distinct types of colony-stimulating factors (CSF) separable by isoelectrofocusing. Type I and type II CSF differ in MW, isoelectric point, CFU-C specificity, and the morphologic type of colonies they stimulate. Type I CSF exhibits higher activity in mouse than in human marrow while type II is more active in human marrow. Type I and II CSF from cultured human pancreatic carcinoma have been purified, type I to apparent homogeneity, and antibody has been prepared against them in rabbits. We have utilized purified CSF and anti-CSF antibodies to label CFU-C fluorescently for the purpose of cell sorting via flow photometry. Human bone marrow cells preincubated with CSF and then treated first with anti-CSF antibody then fluorescein-labeled goat antirabbit globulin retain their ability to grow and form aggregates in the presence of additional CSF. Colonies thus formed exhibit fluorescence, the intensity of which diminishes with increase in aggregate size. These observations provide new insight into the biology of CFU-C and suggest the following: (1) Incubation of marrow cells with CSF for 2 h results in binding of CSF or an antigenic component of CSF to membranes of CFU-C. (2) Bound CSF-anti CSF complex remains on CFU-C membranes through at least 5-6 cell divisions. (3) The approach described offers great potential for the preparation of highly purified CFU-C populations by fluorescence cell sorting.

Antibodies↗
PubMed1982

Physiological studies of exocrine pancreatic secretion in conscious rats. 4. Communication. Effects of anesthesia on flow rate and composition of pancreatic juice.

1. In conscious rats provided with indwelling pancreatic and biliary catheters, the influence of anesthesia was investigated. 2. Ether was applied in concentrations of 4, 6 and 8 Vol % by an evaporator and Na-pentobarbital injected intravenously (30 mg/kg b. w.) 3. Flow rate, electrolytes (ion-selective electrodes and flame photometry), total protein concentration and the amount of several different individual enzyme fractions were determined quantitatively by electrophoresis. 4. During ether anesthesia flow rate and total protein concentration are decreased by about 50% of the control. A certain constant basal flow is established. Na+-Concentration is increased (+15%) and K+-concentration is diminished by about 30-35%. Characteristic changes in the enzyme spectrum are induced. 5. Changes due to pentobarbital anesthesia are as follows: reduction of the mean flow rate (30-35%) with large fluctuations. Corresponding variations of the K+-concentration. Diminution of the protein content without typical changes in the individual enzyme fractions.

Anesthesia, General↗
PubMed1982

[Consecutive spectrophotometric determinations in one cuvette: a new approach for checking the accuracy of single, profile and emergency determination (author's transl)].

A cost effective method for emergency and single assays is presented. By this method, a serial (consecutive) determination of reagent blank, sample, standard, and control serum is performed in one single cuvette and with only one pipetting of reagent. Compared to a sequential determination of sample, standard, and control serum, this is specially economical with regard to reagents and cuvettes. A particular application is seen in the field of prefilled cuvette tests, where the consecutive method allows analysis in the sample and in the control serum, and determination of the required standard absorption in a single test. The results found in the determination of glucose and of aspartate aminotransferase show that the consecutive measuring principle is feasible and even results in a more expressive control of accuracy. If the value found in the assay exceeds the measuring range due to too high a substance concentration or activity, or for photometry reasons, it is immediately seen from the incorrect value for the control serum. The same is not possible in the conventional technique, as it uses two separate tests for the sample and for the control serum.

Aspartate Aminotransferases↗
PubMed1982

[Rapid demonstration of urinary leucocytes with a new leucocyte test-strip. A multicentre cooperative study (author's transl)].

In a study in which eight centres from Austria, France, Germany and Switzerland cooperated anew test-strip for urinary leucocytes was compared with chamber counts of uncentrifuged urine, on a total of 3183 urine samples. There was good agreement between the teststrip and reference test as to sensitivity and clinical significance, and no significant difference to the Cytur-Test, which is already commercially available. However, one advantage of the new test is that the reaction time is shortened to one minute, so that it can be used in combination test-strips (Combur-Test), thus providing uniform reading-off time and measurement by reflexion-photometry. There is no interference by ascorbic acid, but albumin and serum proteins in higher concentrations weaken the colour reaction. Urine-preserving formaldehyde-containing additives produce false-positive reactions. Alpha-methyldopa, salicylic acid, beta-hydroxybutyric acid and acetoacetic acid have no influence.

Ascorbic Acid↗
PubMed1982

Physiological studies of exocrine pancreatic secretion in conscious rats. 5. Communication: circadian rhythms of flow rate and composition of pancreatic juice.

1. In conscious rats provided with indwelling pancreatic and biliary catheters, the circadian variations of flow rate, electrolyte- and protein concentrations are followed. 2. Individual enzymes are separated by Polyacrylamid-Gelelectrophoresis and quantitatively determined by photometry after evaluation of the coloured bands. 3.) Volume flow rate increases towards the evening and reaches maximal values in the early morning hours (2-4 a. m.). 4. A similar nocturnal maximum can be observed for the concentrations and elimination rates of total protein, potassium and bicarbonate, while the concentration of sodium is fairly constant and only slightly decreasing in very high flow rates. 5. Typical circadian variations can be observed for the individual enzyme fractions: at night, the part of amylase is higher and the amount of chymotrypsinogen is lower, together with the increased nocturnal protein elimination. At day time these relations are inversed. 6. This rhythm is also existing in fasting animals, although with reduced basal values and smaller amplitude of variation. 7. In fasting animals the relative part of amylase is smaller compared with that of chymotrypsinogen, probably in relation to the reduced elimination of total protein. 8. The circadian variations of exocrine pancreatic secretion may be primarily inaugurated by hormonal action of hormones, whose release is controlled by nervous centers in the brain.

Animals↗
PubMed1982

Evaluation of antacid suspensions containing aluminum hydroxide and magnesium hydroxide.

Liquid antacid suspensions containing aluminum hydroxide and magnesium hydroxide were evaluated for composition, antacid properties, and product quality. The equivalent aluminum oxide and magnesium hydroxide content was determined by chelatometric titration, and sodium content was determined by flame photometry. Antacid properties measured were acid-consuming capacity, antacid effectiveness (preliminary antacid test, acid-neutralizing capacity test), and pH-stat titration. Content uniformity, consistency of the antacid properties, and microbiological content were examined for each product. Data are presented for 36 products for which samples from four or more lots were obtained. The ratio of percentage of equivalent aluminum oxide to percentage of magnesium hydroxide ranged from 1:0.6 to 1:3.5; this range allows for selection of the desired balance between the laxative effect of magnesium hydroxide and the constipating effect of aluminum hydroxide. Based on a daily dose of 280 meq of antacid, the sodium content of the products tested ranged from less than 2% to approximately 45% of the 500 mg per day of sodium allowed in a sodium-restricted diet. The concept of bioavailability was related to the amount of the antacid reacting at pH 3, 37 degrees C during the estimated gastric residence time of 15 minutes. Antacid suspensions are available which will react almost completely (neutralizing greater than 90% of the theoretical quantity of acid) during the estimated gastric residence time. Approximately 4% of the samples contained unacceptable numbers of bacteria. An antacid suspension cannot be adequately evaluated by a single test; choice of a product should be based on an evaluation that integrates several characteristics including sodium content, time and volume required to neutralize a given amount of acid, and uniformity of content.

Aluminum Hydroxide↗