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PubMed1979

Comparison of natriuretic and diuretic effects of single and divided doses of furosemide.

The natriuretic and diuretic effectiveness of once-daily and twice-daily furosemide administration schedules was compared in a two-way crossover study using six normal subjects. Urine was collected for 24hours before and after administration of the first dose of furosemide. Patients received one 40-mg dose or two 20-mg doses of the drug administered six hours apart. Sodium and potassium urine concentrations were measured through flame emission photometry using lithium as an internal standard. Chloride urine concentrations were determined using colorimetric measurement with mercuric thiocyanate. Results were statistically evaluated by a one-way analysis of variance. Results showed no statistically significant differences (p greater than 0.7) between the two regimens in the cumulative 24-hour excretion of sodium, potassium, chloride or water. The average 24-hour sodium excretion following a single 40-mg furosemide dose was 268.9 mEq, while that following administration of the two 20-mg doses was 294.2 mEq. Differences during various intervals within the 24-hour collection period were consistent with the relative sizes of doses administered. It would appear that single daily dose administration regimens would be a logical beginning for furosemide therapy, particularly when lower doses are being considered.

Adult↗
PubMed1995

Separation, real-time migration monitoring and selective zone retrieval using a computer controlled system for automated analysis.

High throughput routine analysis of dsDNA fragments or molecular weight determination of proteins via electrophoresis still require significant efforts to obtain results of high reproducibility and accuracy. This paper analyses the use of a fully automated multi-purpose real-time gel electrophoresis system in these applications and evaluates the benefits of this new concept for routine and research. By comparing currently used systems with this new approach, it also addresses the analytical use of information resulting from real-time dynamic migration monitoring via fluorescence photometry over commonly obtained results from post-run fixation, visualization and evaluation at a single time of the separation. The simultaneous separation of components in multi-gel systems, pre-concentration of sample components, and the ability to perform in-gel assays for biological activity are discussed on basis of routine gel separations of restriction enzyme digested DNA fragments, native and denaturing protein separations and enzyme activity determination. Interactive, selective retrieval of separated components in the nano- to microgram range is carried out for real-time isolation of proteins or dsDNA fragments. Results are compared to blotting in respect to ease of use and transfer efficiency and for immediate availability of macromolecules for sequencing or mass spectroscopy. The Windows-based operating software is critically reviewed for functionality, user-friendliness, graphical data representation and GLP compliance for LIMS oriented forensic or certified laboratories. A statistical evaluation of lane-to-lane and gel-to-gel reproducibility of mobility data, quantification and molecular weight determination concludes the paper.

Autoanalysis↗
PubMed1995

[The anti-inflammatory effect of heparin-containing infusion solutions during phacoemulsification].

UNLABELLED: The use of heparin prevented postoperative intraocular fibrin-clot formation in the rabbit after vitrectomy and cyclocryotherapy. A low rate of postoperative intraocular inflammation was observed in our patients receiving phacoemulsification with heparin infusion solution (slit-lamp examination). To verify this effect a randomized, prospective study was performed using laser-flare cell photometry (LFCP) for measuring protein concentration in the anterior chamber. PATIENTS AND METHODS: Seventy-two patients (49-87 years of age) were randomly assigned to one of the following two surgical groups (temporal clear corneal tunnel incision with phacoemulsification): group A: foldable silicone IOL (Chiron C10), no stitch (3.5 mm incision); group B: PMMA-IOL (Pharmacia 809P) with one radial suture (5 mm incision). Fifty percent of the patients in each group received, in addition to the regular phaco infusion, 1 ml of heparin sodium (-H = without heparin; +H = with heparin). Aqueous flare was measured preoperatively as well as on days 1 and 3 following phaco + IOL with LFCP (Modell FC-1000; Kowa Company). RESULTS: In group A1 (-H) or B1 (-H) the mean flare values (in photon counts/ms) increased from a preoperative value of 7.0 +/- 1.7 (mean +/- SD) or 6.9 +/- 1.2 to 20.2 +/- 3.1 or 20.1 +/- 3.0 on the 1st postoperative day, whereas they decreased again to 13.8 +/- 2.9 or 14.8 +/- 3.1 on day 3 following surgery. In groups with heparin sodium A2(+H) and B2(+H) the flare values only increased from 7.2 +/- 1.3 or 7.1 +/- 1.3 to 12.9 +/- 4.0 or 13.8 +/- 3.8 on day 1, and decreased to 8.0 +/- 2.8 or 8.8 +/- 3.0 on the 3rd postoperative day. The mean postoperative flare values were significantly lower in the groups with additional heparin (p < 0.01). CONCLUSIONS: Heparin sodium in the infusion solution during small incision cataract surgery showed an antiinflammatory effect in the early postoperative period. There was no significant difference between the two IOL materials.

Aged↗
PubMed1995

[Monotherapy vs combination therapy with topical prednisolone and indomethacin].

UNLABELLED: The anti-inflammatory effects of topical steroids and nonsteroidal anti-inflammatory drugs (NSAID) are claimed to be additive, according to fluorophotometric measurements. This finding was reevaluated using laser flare-cell photometry. PATIENTS AND METHODS: Thirty patients (61-79 years of age) without pre-existing deficiencies of the blood-aqueous barrier were investigated preoperatively as well as on day 1 and 3 after ECCE with IOL implantation. The laser flare-cell photometer (model FC-1000; Kowa Company) which was used for examination enables sensitive and exact in vivo determination of aqueous flare. The patients were randomly assigned to one of the following three treatment groups: group A, monotherapy with prednisolone 1% eyedrops (Inflanefran forte); group B, monotherapy with indomethacin 1% eyedrops (Chibro Amuno); group C, combination therapy with prednisolone 1% + indomethacin 1% eyedrops. One drop of either drug was administered five times per day to each patient, beginning immediately after completion of surgery. In addition, all patients received antibiotic therapy with gentamicin. Parabulbar or oral steroids were not administered. RESULTS: Under monotherapy with prednisolone, the flare (photon counts/ms) on days 1 and 3 postoperatively averaged 30.9 and 27.8, respectively. Under indomethacin monotherapy, the flare values were similar (no significant differences). Under combination therapy with prednisolone+indomethacin, however, the flare values were significantly lower both on day 1 (24.2) and on day 3 (20.6). CONCLUSIONS: Combination therapy with topical prednisolone+indomethacin thus seems superior to monotherapy with either of these agents. This confirms the previous fluorophotometric finding that the anti-inflammatory effects of topical steroids and NSAID are additive, a phenomenon attributable to different pharmacological sites of action.

Aged↗
PubMed1995

Human alveolar macrophages: comparison of cell size, autofluorescence, and HLA-DR antigen expression in smokers and nonsmokers.

To investigate the influence of cigarette smoking on alveolar macrophages (AM) we compared morphologic and immunocytochemic characteristics of bronchoalveolar lavage cells collected from 10 smokers and 8 nonsmokers. AM were studied using single cell fluorescence photometry. AM of smokers were larger in size (p < 0.001), showed stronger autofluorescence (p < 0.001), and expressed fewer HLA-DR antigens (p < 0.001) compared with AM of nonsmokers. AM of smokers were more heterogeneous in respect to cell size, autofluorescence, and HLA-DR antigen expression. HLA-DR antigen density on AM of smokers was independent of cell size and autofluorescence. This suggests that tobacco smoke reduces HLA-DR antigen expression in AM of different maturational states and that this defective expression of HLA class II antigens is not dependent on the amount of phagocytosed autofluorescent tobacco particles.

Aged↗
PubMed1994

Effect of luminal Cl- and Ca2+ on tubuloglomerular feedback mechanism.

We dissected and perfused in vitro rabbit cortical thick ascending limbs (CTAL) and distal convoluted tubule with the glomerulus attached intact. Basolateral membrane voltage (Vbl) and intracellular Ca2+ concentration ([Ca2+]i) in macula densa (MD) cells were measured with microelectrodes and microscope photometry, respectively. Our data suggest that the apical membrane of MD cell has a Ca2+ entry pathway, and that the basolateral membrane of MD cell has a Cl- conductance, which may be regulated by the [Ca2+]i in MD cell. We next evaluated by measuring the afferent arteriolar diameter with video camera monitoring whether the change in Ca2+ concentration of macula densa tubular lumen indeed affect tubuloglomerular feedback. The data suggest that the changes in luminal Ca2+ as well as Cl- concentration at macula densa independently alter the afferent arteriolar diameter, thus may affect the single nephron glomerular filtration rate.

Animals↗
PubMed1995

[Modern methods of urinalysis].

The author describes work with two apparatuses, Urilux and Miditron, which evaluate by means of reflex photometry as many as ten parameters on diagnostic strips dipped in the examined urine sample. The first apparatus is suitable for doctors' surgeries or in-patient departments, the second larger one for diagnostic laboratories.

Humans↗
PubMed1994

[Viability of corneal endothelium after long-term storage at +4 degrees C in Optisol].

For successful corneal transplantation endothelial cell function of at least 50% is considered necessary. Corneal grafts are often evaluated by morphological criteria, such as endothelial cell size or density. Donor corneas with a storage time longer than 10 days are usually excluded from transplantation. The viability of the endothelium of 35 human donor corneas was evaluated after storage for up to 27 days at +4 degrees C in Optisol storage medium by using the Janus green photometry technique. The results were compared with the endothelial cell density counted. We demonstrated that the human corneal endothelium remains satisfactorily viable (minimum 68% viable cells) for a period of at least 27 days and that morphological changes do not sufficiently reflect the functional intactness of the cornea. Morphological irregularities should be interpreted as a form of compensation by a viable endothelial cell layer.

Aged↗
PubMed1994

Diagnostic and prognostic significance of serum and tissue trace elements in breast malignancy.

50 cases of breast malignancy constituted the study group. 26 age and sex matched formed the control group. Serum and tissue trace element viz copper, zinc, selenium and molybdenum levels were estimated by atomic absorption photometry. The study group showed significant hypercupremia and molybdenemia, hypozincaemia and hyposeleniamia. The reversal of trend was documented after therapy. The tissue level of copper and molybdenum was high and zinc and selenium was low. An association between serum and tissue level of trace element, stage, histological differentiation was observed. It was postulated that levels of trace elements may help in diagnosis and prognosis of disease.

Breast↗
PubMed1994

Relationship between change in erythrocyte sodium and antihypertensive response to enalapril.

To investigate the effects of enalapril and hydrochlorothiazide on erythrocyte sodium and potassium in relation to their effects on BP, 28 men (mean age 46 years, range 22-64 years) with previously untreated essential hypertension (casual DBP > or = 95 mmHg) were randomised to enalapril (n = 14) or hydrochlorothiazide (n = 14) treatment. BP was also measured intraarterially (brachial artery) and the mean arterial pressure (MAP) recorded. Intraerythrocyte sodium and potassium were measured by flame photometry at baseline and after 26 weeks of active treatment in the hypertensive patients and also in 28 age- and sex-matched normotensive control subjects. There was a significant positive relationship between intra-arterial BP and intraerythrocyte sodium in untreated hypertensives, but there was no significant difference in mean intraerythrocyte sodium or potassium content between hypertensive and normotensive subjects at baseline. The distribution of values of intraerythrocyte sodium, however, differed between hypertensive and normotensive subjects. Supine MAP was lowered from 113 +/- 4 to 97 +/- 3 mmHg and from 110 +/- 3 to 102 +/- 2 mmHg on enalapril and hydrochlorothiazide treatment, respectively. BP reduction with enalapril was associated with a significant decrease in intraerythrocyte sodium (P = 0.02), while hydrochlorothiazide had no effect. There was no significant correlation between delta MAP and delta intraerythrocyte sodium after 26 weeks in any of the groups. Intraerythrocyte potassium did not change on treatment with either drug. In conclusion, there wa a significant relationship between intra-arterial BP and intraerythrocyte sodium in untreated hypertensives. Both enalapril and hydrochlorothiazide reduced BP effectively while enalapril only reduced intraerythrocyte sodium.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Quantitative urinalysis with a common predilution on a DuPont Dimension.

Urine was quantitatively analysed for sodium, potassium, creatinine, calcium, urea, uric acid, inorganic phosphate and magnesium in one manual central predilution. The analysis was implemented on a DuPont Dimension and the results were compared with those obtained with our analysers currently in use. Based on modified serum methods and their assessed linearities, the 8 urine constituents were analysed with high accuracy and reproducibility in a 6-fold diluted urine with DuPont reagents. The Dimension method correlated well with flame photometry for sodium and potassium; with the EPOS analyser for creatinine, calcium, uric acid, urea and inorganic phosphate; with atomic absorption spectroscopy for magnesium. All between-run coefficients of variation were smaller than 5%, except for the analysis of sodium in the lower part of the measurement range. However, a dilution ratio of 6 is an acceptable compromise when these 8 constituents are determined collectively from a common predilution, thereby covering the complete measurement ranges for these analytes in urine specimens. An additional dilution step is necessary for only a few urine samples (fewer than 1% of samples for calcium and urea and fewer than than 2% for inorganic phosphate). The combined analysis of these 8 constituents can be carried out only on untreated urine samples. Currently recommended pretreatments, such as acidification for calcium and inorganic phosphate analysis, and uric acid analysis under alkaline conditions, can be avoided.

Evaluation Studies as Topic↗
PubMed1994

Community-based prevention of stroke: nutritional improvement in Japan.

OBJECTIVES: (1) To demonstrate the importance of nutrition, especially sodium restriction and increased potassium and protein intakes, in the prevention of hypertension and stroke in a pilot study involving senior citizens. (2) To design a population-based intervention in the Shimane Prefecture of Japan concerning dietary factors such as low sodium and high potassium, protein, magnesium, calcium and dietary fibre in the prevention of stroke. DESIGN AND METHODS: The intervention study was carried out at a senior citizens' residence and included general health education along with a reduction of dietary salt intake and increases in vegetable and protein, especially from seafood. Sixty-three healthy senior citizens (average age: 74.8 +/- 7.7 years) had their daily meals modified to a low sodium/potassium ratio for four weeks without their knowledge by the use of a potassium chloride substitute for salt, soy sauce and bean paste, which contains much less sodium and more potassium. Monosodium L-glutamate monohydrate used for cooking was changed to monopotassium L-glutamate monohydrate. Blood pressure was measured with the patient in the sitting position. Daily dietary sodium and potassium intakes were assessed by flame photometry from 24-hour urine specimens. Extensive intervention programs were introduced into the Shimane Prefecture, which has a population of 750,000, through health education classes for housewives, home visits by health nurses and an educational TV program for dietary improvement. The mortality from stroke was monitored for 10 years and compared with the average in Japan. RESULTS: The blood pressure lowering effect of reducing the dietary sodium/potassium ratio was confirmed through a pilot intervention study at the senior citizens' residence. The mortality rates for stroke in the middle-aged population from the Shimane Prefecture during the 10 years after the introduction of dietary improvement had a steeper decline in hemorrhagic, ischemic and all strokes than the average for Japan.

Adult↗
PubMed1994

Effect of MK-507 on aqueous humor dynamics in normal human eyes.

The effects of the topical carbonic anhydrase inhibitor, MK-507, on aqueous humor dynamics were studied in 6 normal volunteers. As a baseline study, intraocular pressure (IOP) was determined and aqueous protein concentration was checked hourly by laser flare-cell photometry from 0900 to 1800 hours. One week later, IOP and aqueous protein concentration were determined in the same subjects on the same time schedule with instillation of 1% MK-507 at 1100 hours. After one more week, the same experiment was carried out with oral administration of acetazolamide at a dose of 250 mg at 1100 hours. Topical MK-507 showed the maximum IOP reduction at 3 hours and increased aqueous protein concentration reaching its maximum at 4 hours. Oral acetazolamide showed the maximum IOP reduction at 2 hours and the maximum increase in aqueous protein concentration was at 3 hours. Although the peak effect on IOP or aqueous protein concentration did not significantly differ between topical MK-507 and oral acetazolamide, only oral acetazolamide showed a significant effect at 1 hour. These results suggested that topical MK-507 reduced the aqueous humor production, but it took more time for the ocular effect to become manifest than after administration of oral acetazolamide.

Acetazolamide↗
PubMed1994

Enzymatic determination of sodium, potassium, and chloride in abnormal (hemolyzed, icteric, lipemic, paraproteinemic, or uremic) serum samples compared with indirect determination with ion-selective electrodes.

We evaluated the effect of hemolysis, icteric discoloration, lipemia, paraproteinemia, and uremia on enzymatic methods for determining sodium, potassium, and chloride, according to the National Committee for Clinical Laboratory Standards EP7-P proposals for testing interference from endogenous substances. The sodium, potassium, and chloride assays (reagent kits supplied by Boehringer Mannheim) were based on electrolyte-dependent beta-galactosidase, pyruvate kinase, and alpha-amylase, respectively. The results were compared with those obtained by indirect ion-selective electrodes (ISE), which in turn had been validated by flame photometry. We analyzed the samples with Hitachi 717, 737, and 911 chemistry analyzers and with an IL943 flame photometer. The enzymatic results were in good agreement with those by ISE, the interference-related differences generally being without clinical significance; however, none of the enzymatic methods could analyze grossly lipemic samples.

Bilirubin↗
PubMedDate not supplied

[The study of proliferative epithelial activity in cholesteatoma of the middle ear during cytomorphophotometry].

Epithelial proliferation in colesteatoma and its influence on the subepithelial inflammatory reaction was studied using morphometry and nuclear photometry of specimens. Twenty specimens of colesteatoma and 15 specimens of skin from the external auditory canal were examined. Nuclear content was greater in the basal cells of colesteatoma epithelium than in the basal cells of external auditory canal epithelium, suggesting increased proliferative activity. This activity was found to be reted to the inflammatory infiltrate of the conjunctive tissue and varied in different specimens.

Adolescent↗
PubMed1975

[FDA-hydrolysis for the fluorometrical evidence of a cell membrane alteration in peritoneal macrophages (author's transl)].

The enzymatic hydrolysis of fluoresceindiacetate (FDA) and the intracellular accumulation of fluorescein (fluorochromasia) by murine peritoneal macrophages were photometrically measured in cell suspensions. The intensity of fluorescence (excitation at lambda = 485 nm) was recorded by a right angel detector as a function of time, number of cells per ml, and FDA concentration, respectively. The meter response was found to be directly proportional up to the concentration of the fluorophor of 1.125 x 10(-6) M. In suspension the intensity caused by cells other than macrophages could be neglected. The rate of the fluorescein formation corresponds to the Michaelis-Menten constants (km = 8,34 x 10(-6) M.) Repeated in vivo administrations of some N-mustard benzimidazole derivatives were followed by competitive and non-competitive inhibition of the FDA-hydrolysis, respectively. Consequently, the fluorescence intensity varied, but without an concomitant adequate alteration of the non-specific (alpha-naphthyl acetate) esterase as was being measured by means of photometry of single macrophages in cell smears. Thus, this method seems to be suitable for quantitation of membrane (permeability) alteration induced experimentelly in macrophages.

Animals↗
PubMed1994

[Effect of topical carbonic anhydrase inhibitor (MK-507) on intraocular pressure of normal human eyes].

The effects of topical carbonic anhydrase inhibitor (MK-507) on intraocular pressure (IOP) were studied in normal human eyes. The subjects were 6 normal volunteers. As a base line study, IOP and aqueous protein concentration determined by laser flare-cell photometry were examined from 0900 to 1800 hours. Then, the same time-course examinations were performed in the same subjects with an instillation of 1% MK-507 or administration of acetazolamide at a dose of 250 mg on different days. MK-507 decreased IOP 2 hours after the instillation, and showed maximum reduction of IOP at 3 hours. MK-507 increased aqueous protein concentration 2 hours after the instillation, and reached its maximum concentration at 4 hours. Acetazolamide decreased IOP and increased aqueous protein concentration 1 hours after the administration. Maximum decrease of IOP was obtained at 1 hour after the administration of acetazolamide. An increase in aqueous protein concentration occurred at 1 hour after the administration, but its maximum increase was at 3 hours. Corneal thickness, anterior chamber depth, anterior chamber volume, and serum protein concentration were not affected by either drug treatment. These results suggest that the inhibition of aqueous humor formation causes the reduction of IOP seen in the use of MK-507.

Acetazolamide↗
PubMedDate not supplied

Associated problems of protein electrophoresis, staining and densitometry.

The process of electrophoresis, a separation phenomenon, is mistakenly understood to include the sequential processes ancillary to analyte resolution, that is, staining and quantification, where the latter could be elution followed by photometry or integrating-calculating-densitometry. The theories involved in electrophoresis itself are well worked out and equally well understood but the problems which are associated with separation, chemical reaction to generate a chromogen and quantification, perhaps partly forgotten and perhaps partly ignored, are taken up and described here. They include albumin trail, resolution, unequivalent staining, prestaining and the densitometry problems associated with band widths, opacity effects and polychromaticities.

Blood Proteins↗