Piezoelectric immunosensors for the detection of individual antibiotics and the total content of penicillin antibiotics in foodstuffs.

Piezoelectric immunosensors on the basis of homologous and group-specificantibodies have been developed for detecting penicillin G, ampicillin, and the total content of penicillin antibiotics. The receptor coating of the sensor was obtained by the immobilization of penicillin G or ampicillin hapten-protein conjugates on the polypyrrole film obtained by electropolymerization and activated by glutaraldehyde. The affinity constants and the cross reactivity coefficients have been calculated. This made it possible to estimate the affinity and specificity of the polyclonal and monoclonal antibodies used. The calibration curves are linear in the range of concentrations 2.5-250.0 ng ml(-1) (penicillin G), 2.5-500.0 ng ml(-1) (ampicillin), and 1-500 ng ml(-1) (group of penicillin). The limits of detection are 0.8 ng ml(-1), 3.9 ng ml(-1), which are lower than MRL, established for penicillin antibiotics. The sensors were tested in detecting penicillins in milk, pork, beef, liver.

A piezoelectric immunosensor for chloramphenicol detection in food.

A piezoelectric immunosensor on the basis of electrogenerated polymer for detecting trace quantities of chloramphenicol, a drug which is used in veterinary for treatment and prevention of infectious diseases, was developed. The detection was conducted in a competitive format with the use of hapten-protein conjugate and monoclonal antibodies. The limit of detection is 0.2 ng ml(-1), the calibration curve is linear in the range of concentrations 0.5-100.0 ng ml(-1). Chloramphenicol was detected in food (meat, milk, egg, honey).

[Alkaline phosphatase in mixed saliva in abdominal inflammatory diseases and gestoses].

By applying enzyme electrophoresis in the agar gel prepared on veronal-medinal buffer (pH 8.6) (the substrate was naphthol AS phosphate; the dye was fast blue B or PP), the authors first revealed mixed salivary alkaline phosphatase (AP) that differed in physicochemical properties from the known serum AP isoforms, in 63% of patients with cholecystitis or pancreatitis, in 90% of those with appendicitis, and in 55.3% of pregnant women with second- and third-degree gestoses. After treatment, the detection rate for salivary AP significantly decreased to 16.6, 40.0, and 6.4%, respectively. This noninvasive test may be useful for the additional diagnosis and monitoring of treatment for abdominal inflammatory diseases and gestational toxicosis.

[The medical social and psychological issues of women with mastopathy].

The study revealed that 92.5% of female patients consulted by themselves the physician on the subject of mastopathy were town inhabitants with secondary special and humanitarian higher education from the white-collar social group. The concomitant diseases of digestial organs and urogenital system and the deviant psychological characteristics of personality as well had been registered reliably much more frequently among women with a mastopathy in comparison with the control group. More than 70% of females noted the intensification of mastopathy symptoms after the exacerbation of somatic diseases and nervous stresses. Also, more than 80% of female patients experienced psychological discomfort due to doctor's referral to the oncological dispensary. In authors'judgment, the special-purpose mammological consulting rooms under maternity welfare clinics and polyclinics has to be organized to provide efficient diagnostics, treatment and psychological adjustment of female patients with benignant diseases of mammary glands.

[Immunochemical studies of salivary lactoferrin].

Immunodiffusion assays were used to examine lactoferrin (LF) in the mixed saliva of 1026 patients and 553 apparently healthy individuals. Elevated salivary LF levels were found in respiratory and digestive diseases and diabetes. It is concluded that this non-invasive immunochemical assay is promising in the screening and monitoring of persons during their health examination.

[Piezoquartz immunosensors for assessing the interactions between Yersinia enterocolitica lipopolysaccharides and antibodies to them].

The utility of a piezoquartz immunosensor coated with lipopolysaccharides (LPS) for the quantification of antibody specificities was demonstrated. Immunochemical reactions were monitored according to the changes in the weight of sensor bioreceptor layer with high sensitivity (detection limit, 1.3 microg/ml) and assay rate (10 min) without any additional labels. The capabilities of this sensor were demonstrated by the example of quantifying the cross-reactivity of blood serum antibodies with the LPS of Yersinia enterocolitica serotypes O:3, O:5, O:5.27, O:6.30, and O:6.31. The proposed approach is promising for clinical diagnostics of yersiniosis, an infectious intestinal disease.

[Detection of sulfamethoxazole by a piezoquarz immunosensor]. / Opredelenie sul'fametoksazola s pomoshch'iu p'ezokvartsevogo immunosensora.

A mass susceptible immunosensor for FIA of sulfamethoxazole residues in liquid products was designed. The immunosensor is based on piezoelectric transducer. Hapten-protein conjugate (SMX-Diazo-BSA) immobilized on the preliminarily silanized electrode surface of piezoelectric quartz crystal was used as the bioreceptor coating. Optimization of the FIA conditions permitted to develop a simple and express procedure for one-step detection of sulfamethoxazole in a sample and further regeneration of the bioreceptor layer. The measuring ranges are 1 to 50 ng/ml and the detection limit is 0.15 ng/ml. The detection results were compared with the HPLC data. The advantages of the new procedure are its simplicity and rapid provision of the analysis results, possible direct detection of the analyte without additional label and repeated use of the bioreceptor layer. The new immunosensor was applied to testing of various milk specimens. It was shown that the quantity of sulfamethoxazole in all the specimens was lower than the recommended Euroresidue standards (100 ng/ml).

[Hep-A-in-Vac, a Russian cultured concentrated inactivated vaccine against hepatitis A]. / Izuchenie otechestvennoi kul'tural'noi kontsentrirovannoi inaktivirovannoi vaktsiny protiv gepatita A "Gep-A-in-Vak".

The results of the study of the reactogenicity, safety and immunological activity of Russian cultural vaccine against hepatitis A are presented. The vaccine was found to have specific safety, moderate reactogenicity and pronounced immunological activity. In addition, the study of the prophylactic efficiency of the vaccine in the pre-epidemic period of the outbreak of hepatitis A morbidity in a group exceeding 14,000 adults was carried out. The study revealed high prophylactic efficiency of the vaccine (its efficiency rate was equal to 97.7%). On the basis of materials thus obtained vaccine "Hep-A-in-Vac" was recommended for use in medical practice for the prophylaxis of hepatitis A among adults.

[Study of salivary lactoferrin in prophylactic examinations]. / Issledovanie laktoferrina sliuny pri profilakticheskikh osmotrakh.

Immunochemical testing of salivary samples of 73 patients revealed a positive correlation between increased level of lactoferrin and the presence of chronic pancreatoduodenal diseases (gastroduodenitis, gastroduodenal ulcers, polyps of the antral portion of the stomach, cholecystitis, cholangitis, cholelithiasis, hepatitis, and pancreatitis, correlation coefficient 0.9). The test is proposed as a cheap and informative method for screening of the above diseases.

[Comparative study of the immunogenicity of the inactivated hepatitis A vaccine Hep-A-in-vac from experimental and clinical data]. / Sravnitel'noe izuchenie immunogennosti inaktivirovannoi vaktsiny protiv gepatita A gep-A-in-vak po dannym éksperimental'nykh i klinicheskikh issledovanii.

Comparative analysis of the specific activities of various batches of Hep-A-in-Vac vaccine showed that the immunologic efficacy of the agent directly depended on the content of hepatitis A virus antigen in the vaccine dose. The results of studying the immunogenicity of the agent on volunteers are compatible with the results of experimental studies and indicate that the test of guinea pigs adequately assesses this characteristic. Assessment of the immunogenic properties of Hep-A-in-Vac prepared using improved technology indicates that Russian vaccine injected three times in a dose containing at least 40 U EIA ensures 87.5% seroconversion in adult seronegative volunteers with the mean geometrical titer of antibodies to hepatitis A virus equal to 683 mIU/ml.

[Evaluation of reactivity and immunogenicity of a cultured concentrated inactivated vaccine against hepatitis A "Hep-A-In-Vak"]. / Otsenka reaktogennosti i immunogennosti kul'tural'noi kontsentrirovannoi inaktivirovannoi vaktsiny protiv gepatita A "Gep-A-In-Vak".

Clinical trials of inactivated hepatitis A vaccine Hep-A-in-Vac demonstrated its specific safety and moderate reactogenicity, manifesting by short-term fibrillar twitching of musculus deltoideus at the site of injection. After a course of three immunizations 87.5% seronegative vaccines developed a high level of specific antibodies to hepatitis A virus with at least 100 reverse values of titers. In controls antibody titers remained seronegative in 90% cases. These data indicate evident immunologic activity of Hep-A-in-Vac vaccine.

[Stimulation of the synthesis of C-reactive protein using pyrogenal in non-neoplastic diseases and cancer of the lungs]. / Stimuliatsiia sinteza C-reaktivnogo proteina pirogenalom pri nezlokachestvennykh zabolevaniiakh i rake legkikh.

Method of immunodiffusion titration of rabbit monospecific antiserum (The I. M. Mechnikov Central Research Institute of Vaccines and Sera of the USSR Ministry of Health) in agar was used to measure blood C-reactive protein (C-RP) level in patients with acute pneumonia (32), protracted pneumonia or activation of chronic non-specific lung pathology (101) and lung cancer (153) after a 3-4-week course of complex antiinflammatory treatment and a 10-14-day course of immunostimulation with pyrogenal (The N. F. Gamaleya Research Institute of Epidemiology and Microbiology). A decrease in the incidence (from 81.2% to 14.2%) and level (from 1.4 +/- 0.3 to 0.3 +/- 0.03 mg%) of C-RP was observed in cases of non-tumor pathology whereas in patients with lung cancer those values rose in step with tumor progression (from 72.2% and 0.4 +/- 0.07 mg% at stage I to 96.3% and 1.2 +/- 0.12 mg% at stage IV). Treatment with pyrogenal allowed to identify C-RP in patients with false-negative reaction in all subgroups. Two-week dynamic C-RP curves characterizing non-tumor and tumor pathology of the lung were plotted.