FORMULATION THERMORESPONSIVE NANOCOMPOSITE HYDROGELWITH EMBEDDED PLGA NANOPARTICLES CONTAINING CYTOTOXIC AGENT.

The aim of the study was to develop and characterize the nanocomposite in-situ hydrogel as local drug delivery system of cytotoxic agent. In-situ hydrogel consisting of 15% thermosensitive (Poloxamer 407) and 1% mucoadhesive (sodium alginate) polymers was selected as the optimal formulation by the conducted studies. The influence of nanoparticle concentration on gelation time and temperature has been experimentally established. As a result, the optimum concentration of nanoparticles (5%) is selected, which does not alter the gel forming process. The resulting nanocomposite hydrogel was characterized through Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), rotational viscometer (LVDV-1T). FT-IR spectra confirmed the PLGA nanoparticles presence within the hydrogel matrix through the absorption peak located at 1750 cm-1. SEM images allowed observing the nanoparticles to be homogenously dispersed. The release pattern of the active substance from the nanocomposite hydrogel is following: at 72 h, 64% and 78% of the active substance were released into the phosphate buffer and cell culture area, respectively. Irritation test on hen's egg model revealed that formulated nanocomposite hydrogel did not show damage of vascular system.

BIOPHARMACEUTICAL UNDERSTANDING OF FORMULATION PREPARATION VARIABILITY OF PLGA NANOPARTICLES LOADED WITH ERYSIMUM EXTRACT.

The purpose of this study was to evaluate effect of process and formulation variables on the preparation of Erysimum extract loaded PLGA nanoparticles. The influence of the various biopharmaceutical factors such as type of organic solvent, type and concentration of surfactant, polymer concentration in the organic phase, ratio of organic phase and water phase were studied. Modified emulsification solvent evaporation method was used for preparation of nanoparticles. Based on the performed experiments optimal formulation of nanocomposite is suggested. Nanoparticle size, size distribution and entrapment efficiency were determined. Among five non-ionic surfactants polyvinyl alcohol provided more stable nanocomposite. Influence mechanisms of different surfactants on nanoparticle formation are provided. Water miscible organic solvent, acetone obtained 232 nm nanoparticles with improved size distribution. Entrapment efficiency was increased to 73% by reducing ratio of organic and water phases. Based on experiments nanoparticles with stable, reproducible properties are fabricated.

FORMULATION OF BIODEGRADABLE POLYMERIC NANOPARTICLES CONTAINING CYTOTOXIC SUBSTANCE OF PLANT ORIGIN.

Formulation of novel drug delivery system is one of the approaches for improvement of pharmacological activity of drugs. This implies encapsulation of the API into the biocompatible polymeric material. Objective of the research was formulation of biodegradable amino acid based polyesteramide nanoparticles composing cytotoxic substance of plant origin. Research materials and methods: biodegradable polyesteramide (PEA), alkaloids from Vinca Minor, surfactants (Tween 80, polyvinyl pirolidone, polyvinyl alcohol, Poloxamer 188). NPs size (mean particle diameter) and size distribution (polydispersity index, PDI), and zeta-potential (ZP) were measured by dynamic light scattering (DLS) using a Zetasizer Nano ZS (Malvern Instruments, U.K.) at 25°C, UV spectrophotometer was used for %EE study. Amino acid based PEA particles were fabricated by the modified emulsification method. Based on the studies optimal composition and fabrication condition of PEA NPs was determined. The conditions of the NPs fabrication were as follows: the O/W ratio: 1:10; the solvent: DMSO; polymer concentration in the organic phase: 50.0 mg/mL; surfactants (PVA) concentration in aqueous phase 0.5%,the stirring rate: 1000 rpm. The influence of the various factors such as organic solvents, surfactants, as well as a polymer concentration in the organic phase,surfactant concentration in the aqueous phase,the organic/water phase ratio on the NPs fabrication was studied.The NPs were characterized by size (mean particle diameter & size distribution (polydispersity index, PDI), and zeta-potential (ZP). Increase concentration of the surfactant (polyvinyl alcohol) from 0.1% to 0.5% decrease average particle size from 568±63 to 169±1.66 respectively. EE% was obtained to be around 50%.

EXTRACTION AND CHARACTERIZATION OF HUMIC SUBSTANCES FROM SPHAGNUM PEAT PELOIDS.

The objective of the research was development extraction process of humic substances from sphagnum peat peloids, selection of extragent and characterization of humic substances. The objects of the research: Kolkheti peat peloids (Ispani, Anaklia, Churia, Chirukhi, Peranga) of different formation phases. Research was held using modern instrumental methods of analysis: UV spectrophotometer, Scanning Electron Microscopy, Centrifuge, Dry oven, Ultraturax. In the research extraction process of humic substances from sphagnum peat peloids was developed and composition of humic substances was studied, also E4/E6 humification coefficient was evaluated. Based on the results extraction conditions of humic substances from the peat peloids samples were determined: a) extragent with maximum yield - 1.0N NaOH; b) mixing type - KA-ULTRA TURAX-T18 - 20 000 rpm/min; c) Precipitant of humic substances -10% HCL. Composition of humic substances are studied in the samples and their relatively high content is determined in Anaklia and Churia sphagnum peat peloids. For characterization of humic substances E4/E6 humification coefficient was evaluated. Low ration of E4/E6 < 5 was established in anaklia, churia and ispani peat peloids. High ration of E4/E6 < 10 coefficient is determined in chirukhi and peranga peat peloids.

[Comparative evaluation of effectiveness of traditional serologic and modified methods of herpes zoster laboratory diagnostics].

AIM: Comparative evaluation of effectiveness of traditional serologic and modified diagnostic methods of disease arising due to varicella and herpes zoster virus (VZV) reactivation. MATERIALS AND METHODS: 2 groups of patients were examined. The main group consisted of 39 patients with manifest form of herpes zoster (HZ), control--20 healthy donors. Sex composition of the groups did not differ. Traditional method of serologic diagnostics included determination of anti-gE VZV IgG and anti-VZV IgG and anti-IgM in patient and donor blood sera by using EIA. Modified methods consisted of isolation in density gradient and cultivation for 48 hours of peripheral blood mononuclears (PBMC) in RPMI-1640 complete culture medium containing 10% of fetal bovine serum, 4 mM L-glutamin and gentamycin. Concentrations ofanti-VZV IgG and IgM were then determined in culture medium by using EIA. RESULTS: In all the examined HZ patients and healthy donors anti-VZV IgG were detected in blood. Only in 26 (67%) of 39 HZ patients anti-gE VZV IgG and anti-VZV IgM were determined in blood sera. Among donors false positive results for these markers were detected in 10% and 5% of cases, respectively. During simultaneous determination of anti-gE VZV IgG and anti-VZV IgM the specificity of the method increased to 100%, sensitivity of the diagnostic method based on simultaneous determination of anti-gE VZV IgG and anti-VZV IgM was 59%. During analysis of spontaneous production of anti-VZV antibodies by PBMC in 38 (97.4%) of 39 patients anti-VZV IgG were determined in PBMC culture, anti-VZV IgM production was observed only in 4 patients. In control group false positive results of anti-VZV IgG and IgM production by PBMC was not detected by the modified method (100% specificity). At equal specificity level sensitivity of the modified method based on determination of spontaneous anti-VZV IgG production by PBMC culture was significantly higher than effectiveness of the traditional serologic diagnostics (97.4% and 59%, p < 0.0001). CONCLUSION: The data obtained allow to recommend during diagnostics of manifest and atypical VZV infection forms arising due to endogenous virus reactivation the new modified method of laboratory diagnostics of the disease as having higher sensitivity compared with traditional serologic method.

[In vitro inhibition of the cytopathic action of herpes simplex virus, type 1, with a natural cytokine complex].

The antiviral action of a natural cytokine complex (NCC)--the preparation Superlymph and its peptide antimicrobial fraction (AMF)--in the culture of Vero cells infected with type 1 herpes simplex virus (HSV-1), strain VR-3, was studied. The NCC preparation did not alter the morphology of the cells for 6 days and was not toxic for the culture of Vero cells. The NCC and AMF produced a protective antiviral effect, which was manifested by the inhibition of the cytopathic action (CPA) of the virus. In the presence of the preparation, the CPA of HSV-1 was equal to 10(-4.67) ICPD50, while in the control CPA was equal to 10(-5.60). The fraction containing antimicrobial peptides (protegrins) and isolated from NCC, characterized by the method of mass spectrometry, produced the maximum antiviral effect on the cell strain Vero (10(-4.58) ICPD50). Thus Superlymph, an immunomodulator with antiviral activity, could be regarded as an effective preparation for the treatment of HSV infection. The action of such preparation was aimed at the inhibition of the CPA of the virus and the stimulation of the antiviral protective mechanisms of the cell.

[Enzyme immunoassay system for the detection of low-avid lgG antibodies to human cytomegalovirus ("CMV-diagnost")].

The new Russian enzyme immunoassay system "CMV-Diagnost" based on the detection of low-avid IgG antibodies has been developed for the rapid diagnosis of cytomegalovirus infection. The system was found not only to determine the strained immunity in response to cytomegalovirus, but also to judge the current infection from the avidity index of detectable IgG antibodies with a high degree of validity. The antibody avidity index of less than 30% suggests an acute stage of primary cytomegalovirus infection. The minimum antibody threshold bodies (deltaOD has been established for the correct interpretation of data on low-avid antibodies. deltaOD of > or =0.6 optic units was for the developed test system "CMV-Diagnost. A correlation was found between the serum levels of low-avid antibodies and IgM antibodies to cytomegalovirus at the acute stage of the disease.

[Detection of low avidity IgG as a promising approach to diagnosis of primary herpetic infection]. / Vyiavleniie nizkoavidnykh IgG-antitel--perspektivnyi podkhod v diagnostike pervichnoi gerpeticheskoi infektsii.

A Russian immune-enzyme test-system ("HERPES-DIAGNOST") was designed on the basis of detection of low-avidity IgG antibodies in order to promote the laboratory value of serological examinations of patients with different clinical manifestations of the herpetic infection. The key test parameters were tuned; the immunosorbent production based on antigens (herpes simplex virus--HSV), types 1 and 2, was optimized; and the concentration was chosen for the main reagent that removes the low-avidity antibodies (8 M urea solution) and, finally, the temporal and temperature regimes were selected for testing. A system was elaborated for registering and interpreting the results. The avidity index of antibodies lower than 35% was found to be a reliable criterion confirming the presence of acute primary infection triggered both by HSV-1 and by HSV-2. If there is a relapse of herpetic infection, the avidity index of antibodies can range from 30 to 45%.

[The significance of a mixed congenital viral infection in human antenatal and perinatal pathology]. / Znachenie smeshannoi vrozhdennoi virusnoi infektsii v antenatal'noi i perinatal'noi patologii cheloveka.

Examinations of 202 newborn babies for a representative group of viral infections by detection of viral antigens in cells of urine sediment and in the autopsy materials by indirect immunofluorescence permitted diagnosis of a congenital viral infection in 92% of patients with intrauterine and perinatal pathology; in 72.5% it was a mixed infection. In the patients the virus-virus associations were, as a rule, represented by enteroviruses of Coxsackie group and/or influenza A, B, and C viruses. Most frequently (83.3-100%) mixed virus infection was detected in newborn babies with the severest pathology (meningoencephalitis, encephalitis, sepsis, intrauterine pneumonia), as well as in fatal cases.

[The diagnosis of brain lesions in newborns with an intrauterine herpetic infection]. / O diagnostike porazhenii mozga u novorozhdennykh pri vnutriutrobnoi gerpeticheskoi infektsii.

Enzyme immunoassay and DNA hybridization technique were used to diagnose herpetic infection. Blood and liquor antiherpetic antibodies were detected, with anticytomegalovirus antibodies used as reference ones. Intrauterine herpetic infection was detected in 61.5% of 91 risk group newborns. We should like to emphasize that two laboratory tests should be used to diagnose an intrauterine herpetic infection in newborns. Detection of antiviral antibodies in the CSF is a valuable method for the diagnosis and differentiation of brain involvement in intrauterine herpetic infection.

[Detection of herpes simplex virus by DNA-DNA hybridization method]. / Vyiavlenie virusa gerpesa prostogo metodom DNK-DNK-gibridizatsii.

Eight recombinant clones were obtained by insertion of BamHI fragments of herpes simplex type I viral DNA into a vector plasmid pUC19o. Of the obtained clones 5 were found to hybridize with herpes simplex type I and 2 viral DNA while 3 clones revealed a positive reaction with the Vero cells DNA. A constructed DNA-probe possessing the highest level of activity was selected for further studies. The probe is a BamHI fragment of herpes simplex type I viral DNA labelled with 32P dTTP. Probe sensitivity in blot hybridization is 10 pg for identification of type I viral DNA and 50 pg for type 2 viral DNA. The DNAs of cytomegalovirus and herpes zoster virus do not show positive signals with the probe. The increased sensitivity of the used dot hybridization as compared with biological or IEA antigen identification of the virus was confirmed with the clinical material from 59 patients with the different clinical manifestations of the herpes viral infection.

[The immunotherapy of herpetic stomatitis in children]. / Immunoterapiia gerpeticheskogo stomatita u detei.

Immunoglobulin with a high titer of antiherpetic antibodies (1:640 to 1:1280) was used for the treatment of children with acute and recurrent herpetic stomatitis. The agent was injected intramuscularly, 2 to 4 injections, depending on the disease severity. The results evidence a favorable effect of the drug on the clinical and immunologic parameters of patients suffering from the acute condition and permit a conclusion that this immunoglobulin prevented the development of recurrent forms in the children with the acute disease.

[The evaluation of a commercial EIA test system for determining the specific activity of antiherpetic preparations]. / Otsenka kommercheskoi test-sistemy IFA dlia opredeleniia spetsificheskoi aktivnosti protivogerpeticheskikh preparatov.

The data on the use of a commercial EIA test system for detection of antibodies in control of preparations against herpes simplex and cytomegaloviruses are presented. The enzyme immunoassay test system for antibody determinations to herpes simplex virus produced by the Odessa bacterial preparations enterprise was shown to be suitable for determination of the specific potency (antigenicity) of herpes simplex vaccine. The advantages of this method over the currently used neutralization test were established. Titration of commercial immunoglobulins detects lots with high litres of antibody to herpes simplex virus. For the same purpose, lots of commercial immunoglobulins were tested for antibodies to cytomegalovirus using a West Germany test-system (Behring). It is concluded that enzyme immunoassay test systems for antibody determinations may be used for screening of lots of immunoglobulins of special effects (against herpes simplex and cytomegalovirus infections) both at the stage of serum and final preparation screening.

[Herpetic encephalitis: the clinico-virological aspect of its diagnosis]. / Gerpeticheskii éntsefalit: kliniko-virusologicheskii aspekt diagnostiki.

Eight patients with herpetic encephalitis (HE) and one patient with herpetic meningitis were investigated. The clinical and laboratory investigations (CR, EEG, and others) are described. In all the cases the diagnosis was corroborated with serological and virological tests unraveling the herpes simplex virus. A high-sensitive diagnose the atypical HE cases with subacute and chronic course that is important for correct treatment.

[A simple and rapid method of determining the titer of herpes simplex virus antibodies in a study by immunoenzyme analysis of a single serum dilution]. / Prostoi i bystryi metod opredeleniia titra antitel k virusu gerpesa prostogo pri issledovanii v immunofermentnom analize odnogo razvedeniia syvorotki.

The result obtained in the study of the possibility of using the method for the determination of the titer of antibodies to herpes simplex virus by EIA techniques in a single dilution of the serum under test are presented. This method is based on the determination of the optical density of the serum titer (rcut) in different groups of sera with the use of the assay system, permitting the evaluation of the positive results obtained in the determination of their final dilution. The results obtained with the use of this method showed that error was 50% for high-titer sera, 60% for medium-titer sera and 30% for low-titer sera.

[Dynamics of the formation of antibodies to surface and internal proteins of the herpes simplex virus in a model experiment on rabbits]. / Dinamika obrazovaniia antitel k poverkhnosti i vnutrennim belkam viru sa gerpesa prostogo v model'nom ékpserimente na krolikakh.

It has been shown by immunoblotting that antibodies to HSV-1 nucleocapsid proteins (39-45K) predominate at the early stages of infection (up to day 21 after infection) in rabbits. At later stages (up to day 75) the intensity of bands corresponding to virus-specific glycoproteins (presumably gD, gE, gC) increases. At the same time the level of antibodies to nucleocapsid proteins diminishes. In ELISA the same pattern was obtained using envelope and nucleo-capsid proteins denatured by SDS and 2-mercaptoethanol. The possibility of using individual HSV antigens for the development of highly specific diagnostic ELISA test-systems is discussed.

[Phase-specific protein synthesis in human fibroblasts after synchronization by a double thymidine block]. / Fazospetsificheskii sintez belkov v fibroblastakh cheloveka posle sinkhronizatsii dvoinym timidinovym blokom.

Kinetics of acid-insoluble non-histone protein synthesis during S and G2 cell cycle phases of diploid human fibroblasts and heteroploid transformed cells was investigated. Two distinct groups of protein with different kinetic pattern depending on the cell culture type were revealed. Export of one group of protein and turnover of the other group of acid-insoluble non-histone protein is arrested in heteroploid transformed cells.

Preparation and evaluation of anti-species and antiviral peroxidase conjugates.

Several antispecies peroxidase conjugates from human and rabbit immunoglobulins G (IgG) and a conjugate from IgG fraction of hyperimmune rabbit serum against the membranes of herpes simplex virus type 1 (HSV-1) infected cells have been prepared and characterized. The conjugates when tested in enzyme immunoassay for detection of antiherpetic antibodies in human and hyperimmune rabbit sera, as well as for detection of HSV-1 antigen in infected Vero cells appeared active and highly specific. Comparison with the peroxidase conjugates from antiherpetic IgGs prepared by means of ion- exchange and affinity chromatography has shown similar activities.