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Within the framework of the Federal External Quality Assessment (EQA) System and in the context of postgraduate training improvement for health workers in 2010-2014, specialists from the laboratories of the therapeutic-prophylactic organizations and institutions of the Russian Federal Service for Supervision of Consumer Rights Protection and Human Welfare were examined for their professional competence in microscopically identifying the pathogens of parasitic diseases in feces. The virtual remote educational computer technology tools that included different combinations of 16 helminthic species, 5 intestinal protozoan species, and a number of artefacts, were used. The specialists from 984 laboratories of multidisciplinary therapeutic-prophylactic organizations and hygiene and epidemiology centers in all Federal Districts of the Russian Federation were covered. A total of 8245 replies were analyzed. The detection rate for helminths was 64.0%, including those by a taxonomic group (nematodes, 65.0%; cestodes, 72.0%; trematodes, 55.1%). There was a dynamic decrease in the above indicators. There were low detection rates for trematodes parasitizing the small intestine (Metagonimus, 10.2%; Nanophyetus, 26.2%) and hepatobiliary organs (Fasciola, 59.6%; Clonorchis, 34.9%). The similar trend was seen in the detection rates for the pathogens of geohelminthisms (ascariasis, trichocephaliasis, etc.) and contagious helminthisms (enterobiasis, hymenolepiasis). The level of competence in detecting and identifying intestinal protozoa was much lower than the similar rates for helminthism pathogens. EQA for the laboratory diagnosis of the pathogens of parasitic diseases, by using the virtual tools is a leading element of the postgraduate training system for laboratory specialists. The results of EQA for the laboratory diagnosis of the pathogens of parasitic diseases are a basic material for the development, and improvement of training modernization programs, by applying a modular approach.

In 2010-2013, the quality of microscopic detection of the causative agents ofparasitic diseases in the feces has been assessed by the specialists of the laboratories of the therapeutic-and-prophylactic institutions (TPIs) and Hygiene and Epidemiology Centers, Russian Inspectorate for the Protection of Consumer Rights and Human Welfare, which are participants of the Federal System of External Quality Assessment of Clinical Laboratory Testing. Thirty-two specimens containing 16 species of human helminths and 4 species of enteric protozoa in different combinations were examined. The findings suggest that the quality of microscopic detection of the causative agents of parasitic diseases is low in the laboratories of health care facilities and that the specialists of the laboratories of TPIs and Hygiene and Epidemiology Centers, Russian Inspectorate for the Protection of Consumer Rights and Human Welfare, do not not possess the knowledge and skills necessary to make a laboratory diagnosis of helminths and enteric protozoa. The average detection rates of helminths and protozoa were at a level of 64 and 36%, respectively. The correct results showed that the proportion of helminths and protozoa were 94.5 and 5.5%, respectively. According to the biological and epidemiological classification of helminths, there were higher detection rates for contact group parasites (Enterobius vermicularis and Hymenolepis nana) and geohelminths (Ascaris, Trichuris trichiura, and others). Biohelminths (Opisthorchis, tapeworms, and others) Were detectable slightly worse.

Setting: External quality assessment (EQA) of Mycobacterium tuberculosis drug susceptibility testing (DST) in bacteriological tuberculosis (TB) laboratories in the Russian Federation., Objective: To improve the EQA of DST of first-line anti-tuberculosis drugs using proficiency testing in the Russian Federation., Method: Three rounds of DST proficiency testing using Mycobacterium tuberculosis isolates provided by the Swedish Institute for Infectious Disease Control, a World Health Organization Supranational Reference Laboratory (SRL). In total, 42 TB laboratories in the Russian civilian and prison sectors participated in at least one round of proficiency testing, and 17 laboratories participated in all three rounds., Results: Ninety-seven per cent (87/89) of reports were received for the three rounds: 67% of laboratories in the first round and 86% of laboratories in the second round demonstrated >or=95% accuracy for isoniazid, and respectively 72% and 80% of laboratories in the first and second rounds reported >or=95% accuracy for rifampicin., Conclusion: Coordination with the SRL network resulted in the introduction of 90 well-characterised strains for EQA in the Russian Federation. Successive rounds of DST proficiency testing have helped to identify highly proficient laboratories that will be used as expert laboratories for proficiency testing in the future.

Part of the Federal System of External Quality Assessment of Clinical Laboratory Tests named "PCR-identification of hepatitis C virus (HCV)" and aimed at detection of HCV RNA by polymerase chain reaction (PCR) assay is functioning from 2000. Ninety, 98, and 112 laboratories from more than 50 regions of Russian Federation participated in it in 2000, 2006, and 2007 respectively. Analysis of results of control samples tests, which were performed by participated laboratories, showed increasing proportion of method of amplification in the presence of fluorescent-marked probes both in real-time and in end-point regimens. In these circumstances, significant increase of specificity and sensitivity of tests was observed. In 2007, proportion of correct results obtained by the participants for tests with negative control samples was 96 - 97%, whereas during detection of HCV RNA in concentration 10(3) IU/ml the proportion of correct results was 80 - 83%. Significant proportion of laboratories, which did not detect HCV RNA in concentration 10(3) IU/ml, points on the necessity to improve sensitivity of this important method of laboratory tests.

Analyzing the results of detection of C. trachomatis, M. hominis, and U. urealyticum DNA by the participants of the Federal External Quality Assessment System in 2006-2007 indicated that the share of the fluorescent-probe amplification technique both in the real-time mode and by the end-point tended to increase. The above tendency coincided with the other--the higher proportion of laboratories detecting M. hominis and U. urealyticum at low concentrations (as low as 10(3) copies/ml) although no direct caused-and-effect relation could be established between these two tendencies. In 2006-2007, the section participants demonstrated a sufficiently high specificity (94-98%) in the detection of C. trachomatis, M. hominis, and U. urealyticum DNA while the sensitivity of studies left much to be desired--the proportion of correct results at the concentration of DNA of the above microorganisms of 10(3) copies/ml was as high as 73-82%. The considerable share of laboratories that fail to detect microorganisms at low concentrations suggests that it is necessary to continue work to enhance the sensitivity of this important type of laboratory studies.

An analysis of the data submitted in 2005 by 75 laboratories from 31 Russian Federation's regions, participated in the area of the Federal external quality assessment system (FEQAS) "Polymerase chain reaction detection of Neisseria gonorrhoeae" in 2005 indicated that for identification of Neisseria gonorrhoeae DNA, the FEQAS participants used mainly reagents made by Russian manufacturers; the proportion of correct results obtained in the detection of Neisseria gonorrhoeae DNA in the control samples with a DNA concentrations of 10(4) and 10(5) copies/ml was greater than 90% whereas it decreased to 65-75% when the concentration of DNA was 10' copies/ml; there were no significant differences in the proportion of correct results obtained when two most common sets were used to isolate DNA; the proportion of correct results for control samples with a DNA concentration of 10(3) copies/ml was distinctly higher when hybridization with fluorescence detection was employed as a method for detecting the products of Neisseria gonorrhoeae DNA amplification than electrophoresis was applied.

The paper presents the results of the assessment of the quality of cultural detection and determination of Mycobacterium tuberculosis (MBT) sensitivity at Russia's public health laboratories, which has been made by the Federal System for External Assessment of the Quality of Clinical Laboratory Studies in 2002-2003. The "Bacteriological Detection" Section involved 102 laboratories, of them 57 laboratories also participated in the section "Detection of Drug Resistance". Sixty-three laboratories operated as part of specialized tuberculosis-controlling service facilities and 39 laboratories worked as part of general medical care therapeutic-and-prophylactic institutions. A set of 5 lyophilized samples containing 2.5 x 10(6) M. tuberculosis H37Rv (n = 1); 2.5 x 10(4) M. tuberculosis H37Rv (n = 2); M. fortuitum (n = 1); E. coli in the mixture with autoclaving-killed M. tuberculosis H37Rv (n = 1). 77% of the laboratories could detect in the cultural sample with a high content of M. tuberculosis, by obtaining a correct result; 85% revealed MBT if only in every three MBT-containing samples; 15% of the laboratories could not find MBT in none of the three positive samples. 12% of the laboratories took the growth of microorganisms in the M. fortuitum-containing sample for that of M. tuberculosis. 58% of the laboratories obtained correct results if only in one sample containing M. tuberculosis H37Rv; 42% reported the detection of resistance to one or several antituberculous drugs in the samples containing the drug-sensitive strain H37Rv (a false drug resistance). All the results of determination of drug resistance (DR) in the M. fortium-containing sample were correct. The findings suggest that it is necessary to increase the professional competence of laboratory personnel to the level that ensures the adequate of fulfillment of the standard protocols for detecting MTB and determining DR, which have been introduced by the Ministry of Health of the Russian Federation through its order No. 109 on March 21, 2003.

Criteria for external assessment of the quality of evaluation of 23 biochemical parameters of the blood, meeting the standards of accuracy determined by the Order No. 45 of Ministry of Health of Russia of February 7, 2000 for intralaboratory quality control have been estimated. According to the data of the Federal System for External Evaluation of the Quality of Clinical Laboratory Studies, the percentage of results of analyses of test sera meeting these criteria has been estimated. Introduction of new criteria for external assessment of the quality of biochemical tests into the practice of the Federal System will not notably modify the currently used criteria with regard to the majority of biochemical parameters, except introduction of more stringent criteria for albumin and magnesium and less stringent for creatine kinase.

Three main classes of human serum lipoproteins (LP), very low density lipoproteins (VLDLP), low density lipoproteins (LDLP), and high density lipoproteins (HDLP) were selectively sedimented by heparin and dextran sulfate in the presence of metal ions. These data were used for the development of a method for preparation of fractions of human serum enriched with certain class of LP. Using isolated fractions serums with increased content of total cholesterol, cholesterol of HDLP and triglycerides were prepared. These fractions may be used as control samples for evaluation of corresponding parameters in native samples.

The National External Quality Assessment Scheme for analysis of the urine is presented. It includes 9 parameters: protein, glucose, creatinine, urea, uric acid, sodium, potassium, hemoglobin, and pH. Two lyophilized of liquid control samples of urine (normal and abnormal) are distributed to the participating laboratories. An original evaluation protocol for qualitative and semiquantitative methods is proposed in addition to the traditional statistical approach to evaluation of the results of quantitative methods.

Center for External Quality Assessment in Laboratory Medicine has been organized in Russia. The National External Quality Assessment Scheme for 16 common analyses in clinical chemistry was implemented in 1992 under governmental support. A total of 1180 laboratories wished to participate in the program. 636 laboratories presented the results of analyses of 4 control serum pools, 2 with normal and 2 with increased concentrations of the constituents. Each control pool was analyzed twice allowing separate estimation of the accuracy and precision. Accuracy was assessed as the bias from method-dependent means and reference values. Reference methods were implemented for sodium, potassium, total protein, cholesterol, and triglycerides. Analysis of variance demonstrated that the errors are mainly due to the variability of methodologies in different laboratories, this variability being negligible.

The prevalence of risk factors (RF) to develop cardiovascular disorders alone and in combination has been studied in males aged 20-54 differing by occupation and education. They lived in various cities of CIS and Baltic States. It was established that RF alone and in combination are common among the male population. The risk is the highest in the group of males engaged in hard physical labour (p < 0.05) and in low-education subjects. In subjects with higher education RF are the lowest. RF alone and in combination proved higher in Europeans and Siberians compared to males living in the Central Asia.

A comparative study of hypercholesterolemia and lipid distribution in males aged 20-54 randomly selected in one of the districts of Moscow, St. Petersburg, Tallinn, Kiev, Novosibirsk, Tashkent, Alma-Ata and Bishkek has been performed. A comparative interpopulation analysis involved mean values of blood lipid spectrum: total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDLPC), high-density lipoprotein cholesterol (HDLPC). TC, TG, LDLPC in blood were higher in European region and Siberia than in Middle Asia populations. These findings correlated with hypercholesterolemia prevalence. An average of 50% of European population studied need preventive treatment for hypercholesterolemia.

The paper deals with the contribution of risk factors to the spread of coronary heart disease (CHD) among males living in various cities and towns of Russia, CIS countries and Baltic states. The examination of random representative samples of male populations established that risk factors, such as age, arterial hypertension, obesity, hypercholesterolemia, dyslipoproteinemia, and smoking (p < 0.05), make a significant contribution to the spread of CHD, including acute CHD. Age, arterial hypertension, and body weight (p < 0.01) also make a substantial contribution to the development of CHD. The risk factors play a greater role in the spread of CHD in Tallinn, Alma-Ata, St. Petersburg, and Novosibirsk than in Moscow and Ufa, but in the spread of acute CHD in Tallinn, Kaunas, Ufa, and Alma-Ata than in Moscow and St. Petersburg.

It has been shown that the synthetic lipophilic anion, sodium tetraphenylboron, used at concentrations up to 15 mM causes modification of high density lipoproteins (HDL) by changing the electrophoretic properties of individual lipoprotein subclasses. The densitograms obtained after separation of sodium tetraphenylborate-modified HDL under non-denaturing conditions have a better resolution with respect to subclasses 2a and 2b, which markedly facilitates the analysis of the subfractional composition of lipoproteins.

Advantages and disadvantages of enzymatic assays of total cholesterol content in human blood serum are reviewed. Factors, affecting these assays are discussed: specificity of the enzymes used (cholesterol esterase and cholesterol oxidase), conditions of analysis and composition of the reaction mixture, interference with components of blood serum. Adaptation of the enzymatic assays of total cholesterol estimation for various types of biochemical analyzers, including systems containing immobilized enzymes, is considered.

Differential binding of lipophilic permeant anion-tetraphenylboron by high density lipoproteins is shown. The electrochemical heterogeneity of lipoproteins is explained by the difference in their protein-lipid content.

A study was made of the prevalence of coronary heart disease, risk factors (arterial hypertension, hypercholesterolemia, hypertriglyceridemia, hypo-alpha-cholesterolemia, overweight, tobacco-smoking) and of the relation of coronary heart disease to the risk factors in men aged 20 to 39 years and 40 to 54 years, living in 8 cities of the USSR. The study was carried out on material of random representative samples. It has been established that the prevalence of coronary heart disease and risk factors is bigger among the populations living in the European part of the USSR and Siberia, being lower among the populations of Central Asia. The relationship between coronary heart disease and the risk factors is pronounced to a greater measure in arterial hypertension and overweight and to a less degree in other conditions. Besides, the relation of coronary heart disease to the risk factors is marked to a much greater measure among men belonging to the senior age groups.

Changes of proteinase-inhibitory system values in blood plasma of dogs with experimental acute pancreatitis (EAP) were studied in dynamics. Their diagnostic and prognostic values was appraised. Essential shifts were revealed in the proteinase-inhibitory balance in blood plasma of dogs with EAP of various severity. The concentration of trypsin- and chymotrypsin-like proteinases exceeded the normal values 1.8-3.3 times in these animals. Coefficients expressing the relation of antitryptic and antichymotryptic activities to the activities of the corresponding proteinases in the blood plasma of animals with EAP were indicative of diminished blood plasma inhibitory potential as compared to that in intact animals. The authors are the first to show the diagnostic and prognostic value of the antichymotryptic activity/chymotrypsin in blood plasma of dogs with EAP.

An addition of tetraphenylboron (TPB) at low values of pH results in the formation of a cholesterol-rich pellet after centrifugation. The pellet contains 90-95% of whole serum cholesterol. The pH effectiveness sequences for TPB precipitation of low density lipoproteins are detected. It is assumed that TPB changes the distribution of the charges in the hydrophobic moiety of lipoproteins and increases their ability to precipitate.

The interaction of human creatine phosphokinase isoenzymes with rabbit antibodies and their Fab has been studied. It has been shown that Fab of the antibodies against MM or BB isoenzymes preserve high specificity of intact antibodies and the ability to inhibit creatine kinase isoenzymes. Differences between antibodies and their Fab have been found to exist with respect to the kinetics of binding with homologous isoenzymes: the rate of the complex formation for Fab is significantly higher. The interaction of creatine kinase isoenzymes with intact antibodies and their Fab is not affected by the addition of creatine kinase substrates. The antibodies against MM and BB isoenzymes have been used to study the individual properties of each subunit of the M- and B-type in a hybrid dimer MB. It has been shown that such properties of these subunits as the Michaelis constants, pH dependence and inhibition by homologous antibodies are identical to those of non-hybrid MM and BB isoenzymes, respectively.

A modification is described of the previously developed procedure for isolation of acid stable proteinase inhibitor (ASI) from urine of patients with nephritis. The modified procedure enabled to increase the yield of the inhibitor and to obtain its highly purified preparations. These preparations possessed a property to inhibit effectively the activity of human granulocyte elastase (ki = 10(4) M-1 min-1). The modified procedure is based on affinity chromatography on chymotrypsin-Sepharose 4B, substitution of dialysis by gel filtration on Sephadex G-25, use of alternative methods for concentration of protein fractions instead of membrane ultrafiltration and chromatography on polyamide for ASI depigmentation. The inhibitor yield amounted up to 75% of the initial activity in urine. The possibilities of the human urine ASI use in medical practice are discussed.

A kinetic method of estimating the ratio of mole quota of H and M human lactate dehydrogenase (LDG) subunits is proposed, based on changes in substrate inhibition of LDG isoenzymes with lactate. Stability of kinetic constants for a long period of time is demonstrated. The dependency of activities ratio under low and high substrate concentration on the contribution of mole quota of LDG M subunits is studied. The correlation of experimental and theoretical values is shown to be: r=0.998 p less than 0.001. A comparison is carried out of the content of LDG subunits molar quotas in artificial mixtures with electrophoretic experimental data, a good coinsidence of these values being registered. The informative importance of the method described with standard methods of the estimation of LDG isoenzyme systems is discussed. No effect of components of human diploid cells homogenate and an insignificant effect of blood serum components on kinetic constants of LDG isoenzymes is registered. A dependency of variation coefficients on the enzyme activity is studied, minimal omegan value being 0.6%. The applicability of the method described for the calculation of quantitative content of both LDG subunits in natural objects (blood serum, diploid cell homogenate etc.) is demonstrated.

Resistance of liver, bone, intestinal and placental human alkaline phosphatase isozymes to the effect of L-phenylalanine and urea was studied. The combined treatment with urea and L-phenylalanine increased an accuracy of estimation due to inhibition of bone and intestinal isozymes. A special equation enabled to simplify the calculations. As shown by laboratory and clinical tests, the method developed is suitable for quantitative estimation of alkaline phosphatase isoenzymes.

Properties of human creatine kinase isoenzymes (MM, MB and BB) are investigated. The most pronounced differences in properties of these isoenzymes are found under their urea inactivation, heat denaturation and the inhibition by rabbit antisera to isoenzymes. Differences in values of the Mikhaelis constant and substrate and pH dependencies are much less pronounced. The presence of ADP stabilizes creatine kinase isoenzymes under conditions of urea and heat inactivation. Properties of hybrid MB isoenzymes are found to be intermediate with respect to MM and BB isoenzymes. A mode of the interaction of M and B subunits in dimeric molecules of creatine kinase isoenzymes is discussed.

Interrelations of active sites of tetrameric molecules of human lactatedehydrogenase (LDH), known as intratetrameric catalytic independency of subunits, are studied. Estimation of catalytic activity of subunits, which compose hybrid LDH isoenzymes, is carried out. Ratios of molecular activity of subunits are calculated and a conclution is drawn on the catalytic independency of LDH isoenzymes active sites with respect to substrate inhibition by L-lactate. Possible mechanisms of substrate inhibition of LDH isoenzymes and their inactivation with urea in the view of different interrelations of active sites of these isoenzymes under conditions studied are discussed.