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At least 1,621 records · Page 90Linked to original sources
PubMed1997

Electrolyte disturbances due to ouabain sensitive sodium potassium pump in erythrocytes of children with sepsis.

The possible mechanism of hyponatraemia in septicaemic children was studied by measuring the intracellular red cell sodium in relation to ouabain sensitive Na(+)-K(+) pump by flame photometry. Hyponatraemia and hyperkalaemia were observed in most of the patients. There was a marked elevation in serum sodium levels and a significant reduction in serum potassium levels on recovery following therapy. The alteration in the distribution of electrolytes between plasma and erythrocytes resulted in significantly high levels of sodium and low levels of potassium within the erythrocytes of septicaemic patients which normalized on recovery. The ouabain sensitive sodium efflux rate and ouabain sensitive efflux rate constant were significantly decreased in the membranes of erythrocytes of septicaemic patients which also normalized on recovery. Our findings suggest that it is the intrinsic alterations in the transport capacity of Na(+)-K+ pump which could account for the rise in intracellular erythrocyte sodium and fall in intracellular potassium contents in septicaemic children.

Child↗
PubMed1997

Non-invasive determination of dermal hemoglobin oxygenation and concentration in patients with peripheral arterial occlusive disease.

BACKGROUND: Oxygen saturation (SHB) and concentration (CHB) of dermal hemoglobin are important parameters for the supply of the skin. They may be non-invasively assessed by means of reflection photometry as hemoglobin is predominantly contributing to the skin reflection spectrum. METHODS AND RESULTS: Dermal reflection spectra from the middle of the forefoot and from the tip of the toe of 20 healthy subjects and 61 patients suffering from peripheral arterial occlusive disease (PAOD) were recorded and compared to transcutaneous oxygen pressure (tcPO2). SHB, and tcPO2 were significantly higher in controls: compared to patients (ankle pressure (AP) > 50 mmHg) SHB in the skin of the forefoot was 63.8 vs. 54.5% (p < 0.05), CHB was 0.89 vs. 0.62 aU (p < 0.01). In the great toe SHB was 92.9 vs. 59.9% (p < 0.001), CHB was 2.21 vs. 0.92 aU (p < 0.001). Heating the skin of the forefoot to 44 degrees C yields local dermal vascular reserve capacity: SHB and CHB increased in all healthy subjects (96.4%; 1.44 aU, respectively). SHB decreased at the forefoot in 14 and at the toe in 18 of 21 patients with AP < 50 mmHg. At the toe decrease was found in 50 of 61 patients (sensitivity 82%, specificity 100%). CONCLUSIONS: Local vascular reserve capacity of dermal perfusion is reduced in patients with PAOD, depending on AP. It should be determined preferably in patients with severe PAOD.

Adult↗
PubMed1996

[A micromanipulator for the microscope photometer].

A micromanipulator is described to be designed for micro-operations on cells and for various cytological investigations using microelectrodes especially when cell scanning with inserted microinstrument is required. The baseplate of positioners is a light plate located on the microscope stage immediately. Thus, it is possible to do the following operations: to move the object in the field of vision of the microscope simultaneously with the inserted instrument; to insert several microinstruments into one cell; to make photometry of the cell with the inserted instrument by the scanning method. The positioners bear mechanical micromanipulator which ensures the moving of the instrument in three coordinates (8 mm lengthwise, 3 mm crosswise, and 4 mm in upright position). The micromanipulator can be employed with any type of biological microscopes and makes it possible to use objectives of high magnification (up to 100x). A little weight of the instrument (1 kg) makes it convenient to be used in the expedition.

Animals↗
PubMed1997

International Federation of Clinical Chemistry (IFCC). Recommendation on mean molar activity coefficients and single ion activity coefficients of solutions for calibration of ion-selective electrodes for sodium, potassium and calcium determination.

In principle, flame photometry measures substance concentration, and ion-selective electrodes (ISEs) measure ion activity. However, the situation regarding the comparison of results from the two techniques when applied to blood plasma is complex. The problem can be approached experimentally from the point of view of calibration of ion-selective electrodes with concentration calibrators, and similar procedures are adopted for commercial ISE-based clinical analysers. Nevertheless, there is interest in the evaluation of single ion activities in blood plasma and solutions simulating its ionic composition. Solutions are proposed for calibrating ion-selective electrodes for the determination of sodium, potassium and calcium. It is recommended that the values for single ion activities derived from the Pitzer treatment of mixed electrolyte solutions be adopted, because, although this has some empirical features, it has a sounder theoretical basis than the previously used Stokes-Robinson-Bates hydration approach.

Calcium↗
PubMed1997

Small cell carcinoma of the ovary, hypercalcemic type. A case report with immunohistochemical, ultrastructural and cytophotometric analysis and review of the literature.

Small cell carcinomas of the ovary, hypercalcemic type, are unilateral tumors occurring almost exclusively in young women. 60% of the cases are associated with hypercalcemia. Microscopic examination shows diffuse clusters of small cells and follicle-like spaces. Immunohistochemically, the tumor cells are positive for epithelial and mesenchymal markers, and ultrastructurally they contain an abundance of dilated rough endoplasmatic reticulum and numerous free ribosomes. By DNA-single cell photometry, the neoplastic cells show a diploid DNA-content.

Adult↗
PubMed1977

[Ion concentration in the cerebrospinal fluid in multiple sclerosis].

The concentrations of electrolytes Na, K, Ca, Mg, and Cl and trace elements Cu and Zn were determined in the lumbar cerebrospinal fluids of forty patients with multiple sclerosis. Metal ion concentrations were measured using atomic absorption spectroscopy and flame photometry, respectively. Compared with corresponding values obtained from a control group, statistically significant increases in concentration of Na, Cl, Ca, and Zn have been found. Also reported are the results of determinations of ion concentrations in cerebrospinal fluids obtained from patients suffering from diseases other than multiple sclerosis. Possible causes of deviations from the norm are discussed.

Calcium↗
PubMed1997

Changes of dermal haemoglobin oxygenation and concentration in healthy subjects and in patients with peripheral arterial occlusive disease during and after acute ischemia.

BACKGROUND: Oxygen saturation (SHB) and concentration (CHB) of dermal haemoglobin play an important role in the nutrition of the skin. In patients with severe peripheral arterial occlusive disease (PAOD) they are reduced at the forefoot. We investigated the changes of the named parameters during an acute ischemia and during reactive hyperemia using an occlusion test. PATIENTS AND METHODS: Dermal reflection spectra were conducted from the forefoot of 11 healthy subjects and 39 patients with peripheral arterial occlusive disease of various stages at rest, during, and after an arterial occlusion at the thigh. Using a multicomponent analysis SHB and CHB were calculated iteratively. The halftime of the post-occlusive increase of SHB (post-occlusive recovery halftime PORHT) and the relation of post- to pre-occlusive CHB (post-occlusive reactive hyperemia PORH) were calculated to estimate the dynamic of the post-occlusive inflow of blood. TcPO2 (37 degrees C) was additionally determined at the forefoot. RESULTS: In patients from stage III and IV all resting values were lower compared to controls. TcPO2 decreased in all persons to 0 mm Hg during the occlusion, SHB was between 0 and 10%, while CHB remained unchanged. In healthy subjects and in patients with claudication the post-occlusive values exceeded the preocclusive ones, while in some patients with higher stages of the disease this could not be found. There was a marked, on the stage of the disease depending difference in the post-occlusive course between controls and patients: in healthy subjects it took only 5.5 +/- 4.8 s until SHB reached half of the maximum value, in patients from the stage IIa group 26.8 +/- 16.9 s (p < 0.001) was measured while in stage III and IV the value was 132 +/- 75 s (p < 0.001). CONCLUSIONS: During ischemia a decrease of the haemoglobin oxygen saturation (SHB) and tcPO2 was found. Haemoglobin concentration (CHB) remained constant, hence a significant shift of blood from skin to muscle did not take place. PORHT was selectively dependent on the stage of the disease. The occlusion manoeuvre enhances the significance of reflection photometry in PAOD.

Adult↗
PubMed1997

Ionic requirements in histamine-evoked potassium efflux in guinea pig pancreas.

Guinea pig pancreatic segments were superfused during 10 min with physiological saline solutions containing 10(-6) M acetylcholine (ACh) or histamine (10(-3)-10(-6) M) and the potassium concentration in the effluent [K+]o) was measured by flame photometry. Histamine evoked a transient increase in [K/]o. The removal of calcium from the superfusing solution and addition of 10(-4) M EGTA caused a significant reduction in the histamine-evoked potassium outflow. Replacement of chloride (Cl-) in the physiological salt solution by nitrate (NO3-) caused a significant reduction in the histamine-evoked potassium release. However, when Cl- was replaced by bromide (Br-) the response to histamine was unaffected. Pre-treatment of pancreatic segments with furosemide (10(-4 M) or ouabain (10(-3) M) caused a marked reduction in the histamine-induced potassium release. The results suggest that ionic requirements in histamine-evoked potassium release are the same as those in acetylcholine-evoked potassium efflux.

Acetylcholine↗
PubMed1997

[Intraindividual element distribution in the distal femur].

Elemental analysis of archaeological bone is a useful tool for intra- and inter-population research. Possibly an intraindividual elemental analysis could also reveal individual influences from the personal life history. The distal part of an archaeological femur was prepared in 48 samples (6 heights, 4 locations, compact/spongious bone). The elements Ca, P, Pb, Sr and Zn were measured by atomic-absorption-spectrometry and photometry. Statistical tests were used to study similarities and differences. In addition, a sample was taken from the middle of the diaphysis to compare these results with the concentrations of the distal part of the femur. The results show a specific distribution for each element. Similarities were only found between Ca and P. A likely interpretation of intraindividual element data is not yet possible due to the lack of the knowledge of the intraindividual element distribution. More intraindividual studies like this one are recommended.

Adult↗
PubMed1997

Pharmacokinetics and pharmacodynamics of triamterene and hydrochlorothiazide and their combination in healthy volunteers.

Although triamterene has been in clinical use for over 30 years, the linearity of triamterene kinetics was not systematically tested. Moreover, although triamterene is mostly applied concomitantly with thiazide-type diuretics the interaction of triamterene (TA) with hydrochlorothiazide (HCT) is subject to a controversial discussion. Therefore, the aim of this study was to examine the dose linearity of TA and the pharmacokinetic and pharmacodynamic interaction of triamterene and hydrochlorothiazide. In the first study 10 healthy volunteers received 0, 12.5, 25, 50, and 100 mg triamterene orally in a balanced crossover design. In the second study 0, 25, and 50 mg TA with 12.5, and 25 mg HCT, respectively, were administered to 12 healthy volunteers. Urine volume and concentration of sodium, TA, hydroxytriamterene sulfate (OH-TA ester), and HCT were measured by flame photometry and thin-layer chromatography, respectively. The observation period for each treatment was 3 days and the drug was given on the second day. Sodium excretion was increased by both drugs. Renal excretion of both TA and OH-TA ester seemed to be reduced at higher doses. However, statistical evaluation revealed no significant (p = 0.37, and p = 0.20, respectively) deviation from linearity. Renal excretion of HCT was not affected by TA and vice versa. However, renal excretion of OH-TA ester is significantly reduced when HCT is administered concomitantly. The renal excretion rate of sodium can be described by a common Emax model when the effects of the excretion rates of both TA and HCT are additive. It is concluded that the pharmacokinetics of TA is linear within the tested dose range and that pharmacodynamic additivity of HCT and TA is not due to a pharmacokinetic interaction. The results support the hypothesis of a sequential nephron blockade for both drugs acting on different tubular segments.

Adult↗
PubMed1997

[Reversible red cell aggregation in children with insulin-dependent diabetes mellitus].

Red cell aggregation has been studied by photometry in 47 children with insulin-dependent diabetes mellitus. The disease was associated with boosting of reversible red cell aggregation, which was most of all expressed during metabolic decompensation with ketoacidosis. When metabolic subcompensation was attained, this parameter did not completely normalize and still had to be corrected.

Adolescent↗
PubMed1997

Renin-angiotensin system and myocardial collagen matrix: modulation of cardiac fibroblast function by angiotensin II type 1 receptor antagonism.

BACKGROUND: Left ventricular hypertrophy is an adaptive process to increased loading of the left ventricle. This condition becomes pathologic with impaired myocardial function if the various tissue compartments of the myocardium (myocyte, interstitial and vascular compartments) are inhomogeneously altered, particularly if myocardial fibrosis occurs. In arterial hypertension, myocardial fibrosis is known to occur in association with activated circulating or local renin-angiotensin systems and includes reactive perivascular and interstitial fibrosis in both the pressure-overloaded hypertrophied left ventricle and the normotensive non-hypertrophied right ventricle. Therefore, it appears that hemodynamics are not primarily responsible for the adverse myocardial collagen matrix remodeling in hypertensive heart disease. Accordingly, we studied the interaction between cultured adult rat cardiac fibroblasts, which express messenger (m)RNAs for types I and III collagens, the major fibrillar collagens in the heart, and angiotensin II (Ang II), the effector hormone of the renin-angiotensin system. OBJECTIVES: Specifically, we sought to determine whether Ang II stimulates total collagen synthesis and the expression of type I collagen mRNA in cultured adult rat cardiac fibroblasts, and to investigate the effects of Ang II on intracellular Ca2+ levels. MATERIALS AND METHODS: Adult rat cardiac fibroblasts were cultured in Dulbecco's Modified Eagle's Medium + 10% fetal calf serum and incubated for 24 h with Ang II with or without specific Ang II type 1 or type 2 receptor antagonists. Collagen synthesis was measured using a 3H-proline incorporation assay, and type I collagen mRNA was determined using reverse-transcriptase polymerase chain reaction. Intracellular Ca2+ transients were measured by fast fluorescence photometry using the fluorescent dye fura-2-acetoxymethylester. RESULTS: We found a 76% increase in type I collagen mRNA in cultured cardiac fibroblasts after a 24-h incubation with Ang II, and this was abolished by simultaneous incubation with the Ang II type 1 (AT1)-receptor antagonist candesartan. Likewise, total collagen synthesis was stimulated by Ang II in a dose-dependent manner, and this stimulation was also counteracted by candesartan. Additionally, incubation with Ang II resulted in a significant dose-dependent increase in intracellular Ca2+ transients which was also abolished by treatment with candesartan. CONCLUSIONS: Ang II stimulates collagen synthesis in cultured adult rat cardiac fibroblasts via AT1 receptors, most likely using Ca2+ as a second messenger. These findings suggest a direct interaction between Ang II and cardiac fibroblasts in mediating myocardial fibrosis in arterial hypertension, leading to pathologic left ventricular hypertrophy with initially impaired diastolic and ultimately reduced systolic function of the left ventricle. The AT1-receptor antagonist candesartan cilexetil, which is the prodrug of the active compound candesartan, may prove valuable in preventing or regressing myocardial fibrosis in hypertensive heart disease.

Angiotensin II↗
PubMedDate not supplied

Degree of polymerization dependent nucleic acid adsorption on cellulose.

Experimental data on bichromatic multiple light scattering enhanced absorbance (MLSEA) photometry at 260 and 350 nm of nucleic acid chromophores on dried chromatography paper disks, previously impregnated with RNA solutions are analyzed. The extrapolated X(O) value of the adsorbed chromophore mole fraction X (9, 10) and mainly its slope dX(O)/dlogD in terms of the logarithmic plot of Debye length D (A), are strongly dependent upon the polynucleotide degree of polymerization P, providing a new ultramicroanalytical, rapid and simple parameter for relative P measurements. New experimental evidence is brought for the two-step adsorption model of polyelectrolytes at charged interfaces.

Adsorption↗
PubMed1998

[A new rapid automated photometric method in analysis of quantitative indicators of food product contamination].

Thirty-five specimens of pasteurized milk were tested for bacterial contamination by rapid autocalibration photometry for liquid, semiliquid, and homogenized hard foodstuffs, developed by the Ecotest Firm, Russia. Photometric (turbidimetric) analysis was carried out using the Labsystems (Finland) iEMS Reader plate photometer and Russian Analitika BACT software. The results of traditional analysis and the new rapid method developed by Ecotest were in good correlation, the differences did not surpass the magnitude of errors of measurements. The new method takes just 10-15 h instead of the routine 72 h and requires 300 times less nutrient media.

Animals↗
PubMed1998

[Usefulness of SPECT in the study of Alzheimer's disease].

Single-photon emission photometry (SPECT) images of the brains of 60 patients with Alzheimer's disease (AD) were compared with the brain scans of 16 healthy controls of the same sex and similar ages. SPECT was repeated one year later in 16 of the AD patients. Perfusion indices for frontal, parietal, temporal and occipital regions of patients and controls were compared (Student's tests). Flow alterations were located and symmetry examined. The correlation between perfusion index for each cortical area and MMSE score was assessed (Pearson's r). Perfusion alterations were present in all except one AD patient, and in 65% of AD patients such alterations were in the parietotemporal cortex. Severity of cognitive impairment in AD patients was related to perfusion changes in the left posterior temporal region. Forty-four AD patients showed asymmetrical distribution of tracer and in 73% perfusion changes were predominantly in the left hemisphere. Altered brain blood flow is common in AD and onset is early. The parietotemporal location of defective perfusion is of great diagnostic value. Asymmetry is common and the left hemisphere is most often affected.

Aged↗
PubMed1994

Salivary protein and some inorganic element levels in healthy children and their relationship to caries.

The levels of salivary proteins and some inorganic elements were measured in healthy children who were divided into 3 groups according to dentition. The study was prompted by the fact that there have been few studies on salivary composition and most of them have measured only a few components in children. Salivary protein was determined by the method of Lowry; protein electrophoresis carried out as described by Laemli; Na and K concentration was measured by flame photometry and Ca, Mg, Cl and P measured colorimetrically using Randox diagnostic kits. Significant differences were found between the groups for Mg, Na, total protein and some protein bands (obtained by electrophoresis). In all dentition groups, there was no significant difference in any of the levels between the children with and without caries. Salivary inorganic composition, total protein concentration and some protein bands rose linearly with age. Salivary protein and all the above inorganic element levels rose linearly with total caries surface area (Ds + ds), except for Mg which decreased linearly. Some of the protein bands decreased with Ds + ds.

Adolescent↗
PubMed1998

Nutritional potassium status of healthy adult males residing in the rural northeast Thailand.

Sixteen villages from rural areas of 8 provinces in the northeastern region of Thailand were randomly selected as study sites. Data on potassium (K) contents in 24-hour urine and serum samples of 93 healthy adult volunteer males aged 20-50 years old were completely collected and covered all 3 seasons of the year. The method of direct weighing of food was used to assess K intake in 13 subjects. K loss through sweat during working (9 hours) in the field was measured in 14 subjects by soaking their worn-clothes in distilled water after which K contents were measured by the flame photometry method. The results showed that the means urinary K excretion of 93 subjects were less than that of the cut-off value for normal (> or = 30 mmol/day) in all seasons of which 76.71%, 90.71% and 81.02% of the urine were categorized as hypokaliuria in the hot, rainy and cold seasons, respectively. In the case of serum K of these subjects, though the mean values were within a normal limit (> or = 3.5 mmol/l), 36.56%, 34.41% and 29.03% of the serum were classified as hypokalemia in the hot, rainy and cold seasons, respectively. In the assessment of K intake, it was clearly demonstrated that the values in all 3 seasons were much lower than that of the estimated safe and adequate daily dietary intake (ESADI) of K for the westerners (1975-5625 mg/day), i.e., the means of intake in the hot, rainy and cold seasons were only 807 +/- 172, 877 +/- 257 and 902 +/- 227 mg/day, respectively. Furthermore, K loss through sweat in the cold and the hot seasons were as high as a third (7.4 +/- 2.4 mmol/day) and a half (11.5 +/- 1.6 mmol/day), respectively, of the urinary excretion. Though the total body K contents were not evaluated in this study, our results suggest rural people in the northeast region of Thailand may be in a state of K deficiency. The severity is probably worsened in the hot season as seen from the tendency of decrease in serum K levels among 650 renal stone formers and 260 blood donors in this season.

Adult↗
PubMed1998

Copper and ceruloplasmin levels in serum of women with breast cancer.

40 cases of breast malignancy constituted the study group and 10 sex matched formed the control grp. Serum level of copper was estimated by atomic absorption photometry and ceruloplasmin was done by Houchin's method. The study group showed significant hypercupremia and increased level of serum ceruloplosmin. It was postulated that levels copper and ceruloplasmin may help in prognosis & diagnosis of disease.

Adult↗