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At least 127 records · Page 7Linked to original sources
PubMed1992

The long-term evolution of immune deposits in passive Heymann nephritis.

1. To study the long term course of passive Heymann nephritis (PHN), 42 adult male Wistar rats were injected with rabbit anti-FX1A serum (PHN group) and 42 rats received normal rabbit serum (control group). Two animals from each group were sacrificed 2 weeks after the inoculation and 10 animals each from the control and PHN groups were sacrificed 4, 13, 25 and 53 weeks later. 2. The PHN group exhibited a significant elevation in 20-h proteinuria which lasted from the first week (control group, 9.19 +/- 0.87; PHN group, 25.3 +/- 2.66) to the 25th week (control group, 22.6 +/- 2.15; PHN group, 66.7 +/- 10.4) except for week 17. From week 29 to week 53 there was no statistical difference between the 2 groups. 3. Light microscopy showed no difference between the kidneys of PHN and control rats. Immunofluorescence microscopy in PHN rats showed granular deposition of autologous and heterologous IgG on the glomerular basement membrane (GBM), whose intensity and pattern did not change during 53 weeks of observation. 4. When examined by electron microscopy the glomeruli of PHN rats showed: a) electron-dense deposits which were initially subepithelial and homogeneous and later intramembranous, granular and often surrounded by an electron-transparent halo; b) focal thickening of the GBM at the sites of intramembranous deposits; c) effacement of podocytes located close to the deposits; d) "penetration" of the podocytes into the GBM associated with the deposits; e) presence of osmiophilic granules in the cytoplasm of the podocytes located inside the GBM similar to the granules of the deposits next to them. The association of the penetration of the podocytes into the GBM with the deposits and the presence of the osmiophilic granules inside the foot process have not been described previously in PHN.

Animals↗
PubMed2004

The level of some acute phase proteins, total protein, gamma-globulins and activity of lysozyme in blood plasma of rats supplemented with vitamin E and exposed to ozone.

In rats exposed for 28 days (5 hours a day) to ozone at a concentration of 0.5 ppm and receiving alpha-tocopherol at doses of 4.5 mg/rat and 15 mg/rat, levels of acute phase proteins (APP)--C-reactive protein (CRP), ceruloplasmin (Cp), total protein, gamma-globulins, and activity of lysozyme in blood serum were studied. The assays were performed in the presence of respective control groups, i.e. rats receiving the same doses of alpha-tocopherol but not exposed to ozone, a group of animals not supplemented with vitamin but exposed to ozone, a group of animals injected with physiological fluid and a control group not subjected to any of the treatments. The study revealed that the ozone-exposed animals had an increased lysozyme activity and a decreased total protein level. However, in rats protected by alpha-tocopherol and exposed to ozone, the concentration of APP, lysozyme activity and total protein were found to be decreased. Similar relationships also occurred in animals receiving alpha-tocopherol and not exposed to ozone.

Acute-Phase Proteins↗
PubMed1991

[Determination of urinary protein using the biuret method].

Interlaboratory inspection of the quality of laboratory investigations in the Saratov region, carried out in 1987-1988, has revealed a 9 to 50 percent share of unsatisfactory results of measurements of urinary protein by the Roberts-Stolnikov method. This fault was not mended despite the measures taken and the errors detected in the activities of clinical diagnostic laboratories. Analysis of the relevant literature has led the authors to a conclusion that the biuret method, the most specific and sensitive of all the universal methods, should be given preference to. The final stage of the investigation is carried out with the use of a KFK-2M photoelectrocolorimeter. A standard curve based on albumin calibration solution was plotted to estimate the results. At present 15 clinical diagnostic laboratories of this region are using the biuret method. Their results have improved, as evidenced by interlaboratory quality control: the share of satisfactory results of urinary protein measurements makes up 83 to 100 percent.

Biuret Reaction↗
PubMed1986

The Coomassie Brilliant Blue method underestimates drug-induced tubular proteinuria.

The sensitivity of the Coomassie Brilliant Blue (CBB) procedure differs for different proteins. To investigate the impact of this variability on clinical measurements of proteinuria, we collected urine specimens from patients with glomerular disease or drug-induced tubular nephrotoxicity and compared urinary protein concentrations as determined by the CBB method with those obtained by the biuret method. The CBB method underestimated the protein concentration predicted by the biuret method by as much as eightfold in specimens with low proportions of albumin. Determinations of protein by the CBB method in serially diluted urine specimens from patients with tubular damage also deviated from linearity by as much as twofold for protein concentrations less than 1 g/L. We conclude that CBB binding is relatively insensitive for measuring proteins specifically associated with tubular damage and hence may be inappropriate for clinical use.

Biuret Reaction↗
PubMed1978

[Refractometric measurement of total serum protein, comparison of refractometry and biuret test (author's transl)].

Study on the Refractometric Determination of Total Protein in Serum, Comparison of the Refractometric and Biuret Method. Total protein concentration in serum was determined by the aid of the Abbé-refractometer and the biuret method. Both methods showed a good precision and accuracy. The investigation was carried out in 241 sera with normal bilirubin (up to 1 mg/100 ml), cholesterol (up to 200 mg/100 ml) and urea (up to 23,0 mg/100 ml) concentration, in 43 sera with increased (10,6-26,6 mg/100 ml) bilirubin concentration, in 129 sera with increased (200-520 mg/100 ml) cholesterol concentration and in 43 sera with increased (23,0-155,3 mg/100 ml) urea concentration. The comparison of the refractometric values with the values obtained by the biuret method in the 241 sera with normal bilirubin, cholesterol and urea concentration (correlation coefficient = 0,971) showed a close correlation and in the 43 sera with increased bilirubin concentration (correlation coefficient = 0,958) an acceptable correlation. However no close correlations were observed in the 129 sera with increased cholesterol concentration and in the 43 sera with increased urea concentration. The correlation lines diverged proportional with the increase of cholesterol and urea concentration from the expected correlation lines.

Bilirubin↗
PubMedDate not supplied

Standardization of serum protein analyses.

A brief historical review is presented of the development of bovine serum albumin as a standard for the determination of serum total protein. Bovine serum albumin is now available as a standard reference material from the National Bureau of Standards. Also reviewed is the present status of the immunoglobulin standards.

Biuret Reaction↗
PubMed1984

Direct analysis for urinary protein with biuret reagent, with use of urine ultrafiltrate blanking: comparison with a manual biuret method involving trichloroacetic acid precipitation.

We describe a method for measuring urinary protein with a centrifugal analyzer. Biuret reagent is used, and blanking with an ultrafiltrate of urine eliminates interferences from the nonprotein, biuret-positive chromogens in urine. We compare results by this new method with those by a manual method in which trichloroacetic acid precipitation and biuret reagent are used. The new method shows good precision and excellent correlation (r = 0.997) with the manual method. The ease and convenience of this assay should make this a useful method for the routine clinical laboratory.

Anti-Bacterial Agents↗
PubMedDate not supplied

[Use of dye binding for quantitative determination of proteins in solutions (review)].

A review is presented of the methods used for estimation of protein content in solutions. These methods are based on measuring of some organic dyes binding with protein--amido-black 10B, coomassy brilliant blue R-250 and G-250, ponso G, violet sulfate, bromphenol blue, naphthol yellow S, orange G. Advantages and limitations of these methods were compared with Lowry et al (1951) method and with some other conventional methods for estimation of protein content. The methods based on dye binding might provide additional information and substitute the Lowry method if an adequate protein is selected for a calibration plot.

Amido Black↗