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The potentialities of photometry in the ultraviolet, visible, and infrared spectra are compared. Errors associated with neglect of the Booger-Lambert-Ber law, nonmonochromic light, inconstant length of optic route, and non-optimal choice of optic density range are analyzed.
The influence of EDTA on B. glabrata has been investigated. Newly hatched snails were exposed to concentrations of EDTA from 1 to 64 ppm, and young (diameter of 6 mm) snails to concentrations of 50, 80 and 100 ppm, for periods of 90 days. Fifty percent reduction of egg productivity has been caused by concentration of 16 ppm of EDTA while 50% of mortality has occurred at about 70 ppm. The calcium and iron content both in treated and non-treated young snails have been estimated by atomic absorption photometry. The uptake of calcium was 40, 83 and 90% less for calcium and 37, 77 and 81% less for iron as compared with the untreated group. The calcium content of the shell was 5--15 times greater than that of the soft body, while the iron content of those two parts was in the proportion of 1:1. These proportions were maintained constant in the treated and non-treated groups. The interference of increasing concentrations of EDTA has resulted in the proportional reduction of growth-rate, reproduction rate and of longevity of the exposed snails.
This experiment was done with a view to exploring the etiologic mechanism and new therapy of otitis media effusion (OME). The amount of lecithin, which is representative of the surfactants in the nasopharynx irrigation wash liquid, was determined by photometry in 40 cases OME and 40 normal controls. The results showed the surfactant of otitis media effusion (8.637 +/- 2.730 mg/L) was significantly lower than that of normal (39.212 +/- 2.437 mg/L) in the nasopharynx irrigation wash liquid (P < 0.01). The surfactant of child group of OME (8.062 +/- 2.925 mg/L) significantly lower than that of normal control(39.787 +/- 2.557 mg/L, P < 0.01). The surfactant of otitis media effusion in the nasopharynx irrigation wash liquid was not associated with the course of OME. These data suggest that the surfactant reduction in the nasopharynx could indirectly reflect the level of the surfactant in the eustachian tube and the middle ear and influence the eustachian tube function. Surfactant reduction may be one of the etiologic mechanisms of OME. Increasing the surfactant in the nasopharynx and eustachian tube could be beneficial to reducing the persistent otitis media effusion.
The work presents data on the state of the neurons of the spinal ganglia and the spinal cord of the lumbosacral part in 96 cats subjected to single stresses (10g) and repeated ones (6g). The material was stained with thionin after Nissl. RNA was detected after Einarson. Photometry of the sections was made in MUP.5. Morphological changes were shown to be more pronounced in sensory cells. The method of cytophotometry established the increase by 25% amount of RNA in their cytoplasm after single stresses. Repeated stresses resulted in depletion of RNA. The amount of RNA returned to the initial level within 2 days after single stresses and within 3 days after repeated rotations. The shifts were much less pronounced in motoneurons.
We investigated the potential role of magnesium (Mg) dysbalance in the pathogenesis of insulin resistance (IR) in patients with mildly-to-moderately decreased renal function (creatinine: 142.8+/-11.0 mmol/l). The data were compared to those of 8 age- and sex-matched healthy controls (CTRL). The standard oral glucose tolerance test (oGTT) was performed in 61 patients. Twenty-two patients were classified as IR according to their values on fasting and after-load immunoreactive insulin concentrations. Serum and total erythrocyte Mg (tErMg) (atomic absorption spectro-photometry) and free erythrocyte Mg (fErMg) concentrations ((31) P NMR spectroscopy) were determined prior to and two hours after the glucose load. Ten out of 39 insulin-sensitive (IS) patients, but only one out of 22 insulin-resistant (IR) patients, had a low basal fErMg concentration (<162.2 micromol/l, chi2, p<0.01). IR patients had higher serum Mg, total erythrocyte Mg and bound erythrocyte Mg (bErMg) concentrations (both before and after glucose load) when compared with the IS group. Both groups responded to the glucose load with a significant decrease in serum Mg concentration (within the normal range), while the IR group also exhibited a decline in tErMg and bErMg. The mean sum of insulin needed to metabolize the same glucose load correlated positively with tErMg (r=0.545, p<0.01) and bErMg (r=0.560, p<0.01) in the IR patients. It is concluded that, at an early stage of renal dysfunction, IR is not associated with the decline in free erythrocyte Mg concentration, but the magnesium handling in red blood cells is altered.
OBJECTIVE: Comparing the contents of total flavonoides of Rhizoma Arisaematis, which collected in different time, regions, different varieties and processed. METHOD: Determining the contents by ultraviolet spectro-photometry. RESULT AND CONCLUSION: The contents were found in the following sequence: 1. the end of July, the begin of July, August, September; 2. Beijing, Shanxi, Sichuan, Anhui; 3. Arisaema erubenscens, A. heterophyllum, A. amurense; 4. unprocessed product, processed product.
AIM: To find with a laboratory study in vitro the concentrations of released potassium (K+) and chloride (Cl-) ions extracted from polycarboxylate cement containing 5% KCl. MATERIAL AND METHODS: Model calibrated blocks of polycarboxylate cement containing 5% KCl were prepared for the study. Every block contained 6.40 mg potassium ions and 5.80 mg chloride ions. The extraction of the ions was performed in stationary conditions with extragent Aqua redestillata at different time periods: 20 minutes from the mixing of the cement, 24 h, 7 days/168 h/, 14 days/336 h/, 30 days/720 h/ and 90 days/2160 h/ at temperature 36 +/- 0.5 degrees C and pH--7. The concentrations of the released K- and Cl- ions in the extract (in mg/10 cm3), as well as their degree of extraction (in percentage) were measured using emission flame photometry and spectrophotometry. The data are analyzed statistically using descriptive statistics, statistical significance being defined at p<0.05. RESULTS: The concentrations of released potassium and chloride ions increased with time and reached their maximum on the 14th day (336 h). The differences with their respective baseline values are statistically significant (P<0.001). The degree of extraction of the active ions is highest on the 14th day (336 h) - (93.12% for the K-ions and 93.10% for the CL-ions). CONCLUSION: The active supplement of 5% KCL in the polycarboxylate cement increases the rate of extraction of the ions, as the concentrations of the released K- and Cl-ions increase with time and reach maximum values on the 14th day (336 h).
A comprehensive ophthalmologic examination of 45 patients (76 eyes) with normal pressure glaucoma (confirmed in hospital by using tonography, computer perimetry with the "Humphrey-720" field analyzer being applied and by photometry of the optic nerve disk with the "Nidec" fundus-chamber being applied) was carried out. Polymorphism of clinical manifestations of the disease and specific features of such manifestations with regard for an initial level of the ophthalmic tone were revealed. Elderly age, the condition of the anterior segment and hydrodynamic parameters close to the age norm, a pronounced saucer-shaped or asymmetric excavation and segment-type nature of visual field defects were found to be more typical for glaucomatous patients with a relatively low intraocular pressure--IOP (< or = 20 mm Hg according to Maklakov). Younger age, dystrophic changes in the iris and drainage zone similar to those occurring at typical primary open-angle glaucoma, low indices of secretion combined with low indices of intraocular fluid discharge, predominant symmetric excavation and diffuse reduction of light sensitivity along the periphery with a predominant damage of the nasal segments were found to be more typical for glaucomatous patients with relatively high IOP (< or = 26 mm Hg). The described clinical aspects enable a timely diagnosis of the disease and an adequate choice of treatment.
To explore the relationship between the reactive oxygen species (ROS) and apoptosis in esophageal carcinoma cells (SHEE85) induced by arsenic trioxide (As2O3), we focused on changes of apoptosis, ROS, and antioxidants. Apoptosis of SHEE85 was confirmed by means of DNA fragmentation stained by Hoechst 33342, Sub-G1 cells scored by flow cytometry and ultrastructure of cells by electron microscopy. To evaluate the level of ROS, the chemiluminescent method was used for measuring the production of superoxide anion (O(-)*2). Lipid peroxide (malondialdehyde, MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were measured respectively by the photometry method. In the cells treated with As2O3 at a concentration of 5.0 micromol/l for 2-24 h, the content of cellular O(-)*2 and MDA was increased, but SOD and GSH-Px were significantly lower in the process of apoptosis in SHEE85. As2O3 at concentration of 0.5 micromol/l did not cause cell apoptosis but promoted cell proliferation. These results suggest that As2O3 at a high dosage (5 micromol/l) causes cell apoptosis and at a low dosage (0.5 micromol/l) causes cell proliferation. The essential mechanisms of cell apoptosis induced by As2O3 may be related to the increase of ROS and decrease of anti-oxidation. ROS and antioxidants participate in the apoptotic pathway of esophageal carcinoma cells.
Investigation into structural, metabolic, and functional conditions of red blood cells was performed in 24 patients with a neurosis (neurasthenia, disturbance of asaptation) with the aid of electrophoretic division of proteins of the erythrocyte membrane, thin-layer chromatography, fluorescent probing of membranes, evaluation of peroxidative oxidation process, scanning and transmission electron microscopy, laser diphractometry, photometry. The patients with neurotic disorders at the early period after the influence of psychogenic factors (up to 3 months) revealed disorganization of lipid and protein composition of the red cell membrane, increase in microviscosity of its lipid phase, impairment of surface architectonics and ultrastructure of red cells, decrease of a deformation ability and increase of aggregate properties of erythrocytes. The authors treat stability of erythrocytes' homeostasis under the long-term influence of psychogenic factors from a viewpoint of adaptive changes in organism under the influence of neurogenic factors.
OBJECTIVE: To introduce the characteristics of the integer multiple rhythm of cultured cardiac myocytes and to explore the cause of its generation. METHOD: Spontaneous beating rhythms of cultured cardiac myocytes were observed with photometry system and stochastic Chay model was used to simulate the experimental results. RESULT: Integer multiple rhythm was observed in the experiment. This kind of rhythm is similar to phenomena of sinus arrest. The integer multiple rhythm similar to that of the experiments was simulated in stochastic Chay model, and was demonstrated to be induced by the mechanism of autonomous stochastic resonance. CONCLUSION: The integer multiple rhythm observed in the experiment might be generated via the effect of autonomous stochastic resonance.
An experimental setting is presented to evaluate the endothelial protection offered by various viscoelastic materials applied in cataract surgery. The substances used were: hydroxypropylmethylcellulosis, a hyaluronic acid preparation (molecular weight 5.10(6), concentration 10 mg/ml), a hyaluronic acid preparation (molecular weight 800 000, concentration: 35 mg/ml), and balanced salt solution as control. The endothelial surface of pig corneas were covered by test substances and spread with a loop of prolene 4.0 suture material in a mechanically standard way. A total of 40 corneas were examined and the amount of endothelial damage evaluated by photometry using Janus-green wash-out, a substance, which selectively binds to damaged endothelial cells or descement membrane. The damaged surfaces differed significantly in all groups of viscoelastic substances and in the control group. Examination showed that the least damage was in group 3, followed by group 1 and the most damage in group 2. Endothelial protection during cataract surgery can be improved by modifications of the substances presently applied.
In order to estimate table salt intake in selected population groups, sodium chloride as well as sodium, potassium were determined in daily food rations. Sodium chloride was determined by Mohr's method, while sodium and potassium by flame photometry. Parallel samples of soups, bread and carbohydrates in the second courses were analysed in the same way. Samples for analysis were collected during a period of 10 days in a State Children's Home (SCH) and in Home for the Aged (HA). The table salt content in food rations from the HA was found between 14.7-24.7 g and in rations from the SCH between 7.9-19.6. In both cases the values were significantly higher than those recommended. The average table salt content in soup from the HA was 1.24 g/100 g and that from the SCH -1.65 g/100 g. A high level of salt was observed also in potatoes, groats and macaroni, the average value being 1.5 g/100g. As regards the size of the portions given, it was found, that soups as well as bread supplied 34% of the total salt content in the food rations, and the carbohydrates in the second courses brought about 14%. It was found, that about 96% of the total salt quantity in the investigated rations was derived from addition of salt during food preparation and from the processed products. The studied food rations contained relatively high quantities of potassium, that completely satisfied the demand for this element of the investigated population groups. The Na:K weight ratio was abnormal, as the results of too high sodium content.
The quantitative description of diffusive and convective mass transport of small solutes in peritoneal dialysis is dependent on accurate determination and appropriate expression of the concentration of investigated substances. For small solutes which easily equilibrate between dialysate and plasma the solute concentration in plasma should be expressed per volume of plasma water (aqueous concentration) and not per volume of whole plasma. Furthermore, the Donnan effect should be taken into account for electrolytes if measured by flame photometry. The common practice of expressing solute concentration per volume of whole plasma (plasma concentration) may result in substantial errors in calculated values of peritoneal transport parameters. To quantify these errors we compared plasma versus aqueous dialysate to plasma ratios (D/P), diffusive mass transport coefficients (KBD), and sieving coefficients (S) for 28 6-h single-dwell studies using glucose 3.86% dialysis fluid. For all substances except glucose non-corrected plasma D/P overestimated corrected aqueous D/P at 360 min by 2% (potassium and sodium) to 8% (creatinine) and, as assessed by the Pyle-Popovich model, non-corrected KBD overestimated true KBD by 12% (potassium) to 41% (urea). Similar results were also obtained for KBD estimation using the Garred model and KBD estimated during dialysate isovolaemia. The use of aqueous instead of plasma concentrations resulted in a substantial change of S for urea but not for the other investigated solutes. These results emphasise the importance of expressing small solute concentrations per volume of plasma water and not per volume of whole plasma in calculations of D/P ratios and mass transport coefficients.
The nuclear DNA contents of 50 thyroid tumors were measured paraffin block samples and needle biopsies by using microscopic photometry, and the diagnostic value of this measurement was examined. Thyroid tumors included 17 papillary carcinomas, 15 follicular carcinomas and 18 benign tumors. The results confirmed the possibility of discriminating between benign and malignant tumors except in cases of follicular carcinoma with minimal invasion. This method seemed to be most valuable in the diagnosis of cases with class III FNA. A review was made of the relation between DNA content and prognostic factors, for example the degree of invasiveness of the thyroid tumor, intra-tracheal invasion, intra-thyroid metastasis and lymphatic metastasis. DNA content was increased only in cases with intra-tracheal invasion.
BACKGROUND: Helicobacter pylori (HP) is a pathogenic factor in the development of different alterations in the gastric mucosa. Superoxide-dismutase (SOD) is a key enzyme of mucosal antioxidant protection. We have detected changes in the activity of mucosal SOD in different diseases caused by HP. MATERIALS AND METHODS: Biopsies were taken upon gastroscopy (n = 131). Activity of SOD was measured by photometry, referred to the amount of protein in the sample. RESULTS: SOD activity of the antrum of HP-positive patients was significantly higher than that of HP-negative ones. There was a significant increase in erosive gastritis. CONCLUSION: In the presence of HP there was a significant increase of the SOD activity in the antrum but not in the corpus. In chronic antral gastritis there was a positive relationship between the SOD activity and both the severity and activity of inflammation. We presume that HP-associated gastritis is predominant in the antrum.
The chemical composition of green seaweed, Monostroma undulatum, Wittrock, growing in the Southern Argentina coast, was studied. Samples were collected in Puerto Deseado, province of Santa Cruz (47 degrees 45'L.S., 65 degrees 55'L.W.), from October to December 1999 and 2000. It has been analyzed six sample during this period. Algae were washed with sea water and dried at room temperature for 24 hs. Moisture, nitrogen, lipids and ashes were determined according to AOAC; fiber (total, soluble and insoluble), according to Lahaye. After mineralization with nitric acid, sodium and potassium were determined by flame photometry, calcium by complexometric method, and phosphorus by Gomori's method. The ranges expressed per 100 g dry algae were: protein (Nx6.25): 12.89-21.85; ashes (g): 33.92-40.05; lipid (g): 0.32-1.47; total fiber (g): 14.36-19.6; digestible carbohydrates (calculated by difference) (g): 20.86-32.48; sodium (g): 7.39-13.11; potassium (g): 1.38-3.18; calcium (mg): 149-226; phosphorus (mg): 190-447; Vitamin C (mg): 159-455. These results show that this green seaweed is an important source for protein, fiber, macronutrients minerals and vitamin C, during the macroscopic period. There was an important fluctuation that must be taken into account to consider the commercial collection to use it in human nutrition.
Requirements, possibilities, and pitfalls of electrolyte (sodium, potassium, and chloride) analysis are reviewed within the light of the experiences in the Academic Hospital St. Radboud, Nijmegen, The Netherlands. In view of the ever increasing demands on short turnaround times, attention is paid to problems with specimen delivery, instrumentation and data distribution. The precision levels of available alternatives for electrolyte analysis namely: flame photometry, direct and indirect ion selective electrode methods, dry chemistry, and the newly developed enzymatic approach for sodium and potassium analysis are discussed.