RESUMEN
The slip and barodiffusion problems for the slow flows of a gas mixture are investigated on the basis of the linearized moment equations following from the Boltzmann equation. We restrict ourselves to the set of the third-order moment equations and state two general relations (resembling conservation equations) for the moments of the distribution function similar to the conditions used by Loyalka [S. K. Loyalka, Phys. Fluids 14, 2291 (1971)10.1063/1.1693331] in his approximation method (the modified Maxwell method). The expressions for the macroscopic velocities of the gas mixture species, the partial viscous stress tensors, and the reduced heat fluxes for the stationary slow flow of a gas mixture in the semi-infinite space over a plane wall are obtained as a result of the exact solution of the linearized moment equations in the 10- and 13-moment approximations. The general expression for the slip velocity and the simple and accurate expressions for the viscous, thermal, diffusion slip, and baroslip coefficients, which are given in terms of the basic transport coefficients, are derived by using the modified Maxwell method. The solutions of moment equations are also used for investigation of the flow and diffusion of a gas mixture in a channel formed by two infinite parallel plates. A fundamental result is that the barodiffusion factor in the cross-section-averaged expression for the diffusion flux contains contributions associated with the viscous transfer of momentum in the gas mixture and the effect of the Knudsen layer. Our study revealed that the barodiffusion factor is equal to the diffusion slip coefficient (correct to the opposite sign). This result is consistent with the Onsager's reciprocity relations for kinetic coefficients following from nonequilibrium thermodynamics of the discontinuous systems.
RESUMEN
The asymmetry effects in gas and electrolyte transport through composite membranes are considered. The interrelation between the kinetic theory and non-equilibrium thermodynamics description of gas mixture transport in channels is discussed. The kinetic expressions for transport and slip coefficients are given. The effect of surface forces on gas transport is discussed. A set of general equations related to gas mixture flows in capillaries and porous media is deduced. The nano-size effects in gas flows are outlined. The theoretical analysis of one-way flow effect and asymmetric separation properties of a two-layer porous membrane is given.
RESUMEN
A broad range of the boundary value problems of the kinetic theory of gases and gas mixtures is considered based on kinetic theory and non-equilibrium thermodynamics. The interrelation of the kinetic theory and non-equilibrium thermodynamics is discussed. The balance equations at the interface are obtained for the case of the boundary layers with peculiar properties. Procedures for deriving the boundary conditions for slightly rarefied gas mixtures are outlined. The problems of calculating slip coefficients are discussed. The specificity of the kinetic effects in the boundary conditions is shown. A set of general relations related to gas mixture flows in capillaries is deduced. The possibility of non-equilibrium kinetic effects in the form of a paradoxical distribution of non-equilibrium temperature is shown. Methods of non-equilibrium thermodynamics are used to obtain the phenomenological equations describing the thermophoresis and diffusiophoresis of particles and cross phenomena. The growth and evaporation of droplets is considered based on kinetic theory and non-equilibrium thermodynamics.
RESUMEN
The seroepidemiological survey of 400,000 persons aged 20-40 years and belonging to different AIDS risk groups, as well as blood donors, for the presence of antibodies to HIV has been carried out on the territory of Lithuania. This investigation has been made with the use of the assay systems "Antigen", "Peptoscreen" and "Vector" manufactured in the USSR, as well as commercial assay systems from foreign manufacturers, such as Du Pont de Nemours Inc., Organon N. V., Abbott Laboratories, Serodia. The comparison of the results thus obtained has revealed that high frequency of false positive results is characteristic of all assay systems under study, including immunoblotting. These data indicate that test systems based on different acting principles should be used for the detection of anti-HIV antibodies. For the first time a HIV-infected resident of Lithuania has been detected. The investigation carried out in Lithuania has shown that HIV infection is not widely spread in this region, but due to some objective reasons this does not preclude the necessity of the constant epidemiological surveillance of this infection throughout this territory in order to bar the way to this infection.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/epidemiología , Síndrome de Inmunodeficiencia Adquirida/diagnóstico , Western Blotting , Reacciones Falso Positivas , Anticuerpos Anti-VIH/análisis , Humanos , Técnicas para Inmunoenzimas , Lituania/epidemiologíaRESUMEN
Using the MBB/11/5 strain originally adapted to the PLC/PRF/5 cell line, reproduction of the virus in diploid cells of human embryo fibroblasts, continuous primate lines (RAMT, FRhK-4) and human urinary bladder tumor (T-24) lines was studied. We obtained HAV DNA sequences (about 99% from vRNA) for the MBB/11/5 strain which were used as a probe for demonstration of vRNA synthesis in the infected cells.
Asunto(s)
ADN Viral/aislamiento & purificación , Hepatovirus/crecimiento & desarrollo , Animales , Línea Celular , ADN/genética , ADN Viral/genética , Hepatovirus/genética , Humanos , Hibridación de Ácido Nucleico , Mapeo Nucleótido , ARN Viral/genética , Mapeo Restrictivo , Cultivo de Virus/métodosRESUMEN
The primary structure of hemagglutinin of the members of three main antigenic groups of current influenza A (H3N2) viruses was determined. A phenomenon of "antigenic mimicry" was found to be due to the accumulation of reversions in hemagglutinin structure at late stages of antigenic drift.
Asunto(s)
Hemaglutininas Virales/genética , Subtipo H3N2 del Virus de la Influenza A , Virus de la Influenza A/genética , Secuencia de Aminoácidos , Variación Antigénica , Secuencia de Bases , Genes Virales , Glicoproteínas Hemaglutininas del Virus de la Influenza , Hemaglutininas Virales/inmunología , Humanos , Virus de la Influenza A/inmunología , Virus de la Influenza A/aislamiento & purificación , Modelos Moleculares , Datos de Secuencia Molecular , Mutación , U.R.S.S.RESUMEN
The study included 230 strains of influenza A (H3N2) virus isolated in the epidemic of 1985. A high degree of heterogeneity of the virus population was established with polyclonal sera, monoclonal antibodies and the method of kRNA-bRNA hybridization for the determination of the genome composition. Among the strains of one epidemic (1985) three antigenically heterogenous groups of strains were detected similar with reference A/Philippines/2/82, A/Ken/1/84, and A/Mississippi/1/85 strains. It was shown that in the process of antigenic drift in some strains there occurred a reversion of the antigenic determinants similar to those of previously circulating epidemic A/Texas/1/77 strain.
Asunto(s)
Variación Antigénica , Antígenos Virales/inmunología , Subtipo H3N2 del Virus de la Influenza A , Virus de la Influenza A/inmunología , Infecciones por Orthomyxoviridae/microbiología , Animales , Anticuerpos Monoclonales , Brotes de Enfermedades , Electroforesis en Gel de Poliacrilamida , Epítopos/inmunología , Hemaglutininas Virales/inmunología , Hibridación de Ácido Nucleico , Infecciones por Orthomyxoviridae/epidemiología , RatasRESUMEN
Treatment of AIDS is a complicated problem since there is a limited set of preparations tested and most of them appear to be ineffective. Their main target is HIV reverse transcriptase. The data presented show that proteolysis inhibitors are able to inhibit HIV reproduction in cell culture. The compounds used in this study, gordox and kontrikal, are officinal drugs and therefore it is worthwhile to study their effect in patients with AIDS.
Asunto(s)
Aprotinina/farmacología , VIH/efectos de los fármacos , Inhibidores de Proteasas/farmacología , Inhibidores de Tripsina/farmacología , Replicación Viral/efectos de los fármacos , Células Cultivadas , VIH/fisiologíaRESUMEN
A/Seal/Mass/80 influenza virus has been shown to be closely related antigenically and genetically to avian influenza H7N7 viruses, however, the virus does not replicate efficiently in avian species but does replicate in most mammals, except mice (Hinshaw et al., Infect. Immun., 34, 351-361, 1981). In order to develop a model defining the molecular changes that occur during acquisition of virulence, the A/Seal/Mass/80 virus was adapted to growth in mouse lungs. The adaptation was accompanied by changes in a number of properties of the haemagglutinin as well as by changes in other genes of the virus as determined by RNA: RNA hybridization.
Asunto(s)
Subtipo H7N7 del Virus de la Influenza A , Virus de la Influenza A/patogenicidad , Animales , Genes Virales , Variación Genética , Hemaglutininas Virales , Virus de la Influenza A/genética , Dosificación Letal Mediana , Pulmón/microbiología , Ratones , Pruebas de Neutralización , Hibridación de Ácido Nucleico , ARN Viral/análisis , Pase Seriado , VirulenciaRESUMEN
Some technological and immunological problems facing the preparation of subunit viral vaccines are discussed. Solubilization of enveloped virus glycoproteins with various detergents has been studied. It has been demonstrated that a novel non-ionic detergent, MESK, can be used to prepare the glycoproteins of enveloped viruses in defined supramolecular forms: monomers, micelles, liposomes and multimeric complexes. These preparations have been tested for immunogenicity. It has been shown that the immunogenicity of glycoproteins in micellar form or in liposomes is comparable with that of the whole virus. The immunogenicity of the glycoprotein complex with the glycoside Quil A appeared to be significantly higher in comparison with the whole virus and was similar to the immunogenicity of glycoproteins mixed with Freund's complete adjuvant.
Asunto(s)
Detergentes , Tensoactivos , Vacunas Sintéticas/inmunología , Vacunas/inmunología , Proteínas del Envoltorio Viral/inmunología , Vacunas Virales/inmunología , Animales , Virus de la Encefalitis Equina Venezolana/inmunología , Sustancias Macromoleculares , Ratones , Ratones Endogámicos BALB C , Octoxinol , Compuestos Orgánicos , Virus de la Parainfluenza 1 Humana/inmunología , Polietilenglicoles , Saponinas de Quillaja , Virus de la Rabia/inmunología , Saponinas , Vacunas Sintéticas/administración & dosificación , Proteínas del Envoltorio Viral/administración & dosificación , Vacunas Virales/administración & dosificaciónRESUMEN
A comparative evaluation of the effectiveness of detection of human immunodeficiency virus (HIV) in persistently infected culture of T-lymphocytes by means of different morphological and immunomorphological methods: fluorescent antibody method (FAM), immune electron microscopy (IEM), negative staining, and ultrathin section technique, was carried out. The FAM was shown to detect virus antigen exclusively in the cytoplasm of large and multinuclear cells but not in the cytoplasm of small size cells. A marked cyclic pattern (3-passage interval) was established in expression of HIV antigen correlating with changes in the ratio of 3 types of cells in the culture and the intensity of HIV virions production detectable in electron microscopic preparations. The phenomenon of variability of HIV production associated with changes in the ratio of different cell types was used for selection of most productive cultures which were employed as the antigen for antibody determination in sera. The study showed good agreement in antibody detection by the FAM and immunoblotting method.
Asunto(s)
Serodiagnóstico del SIDA/métodos , Antígenos VIH/análisis , Línea Celular , Técnica del Anticuerpo Fluorescente , VIH/ultraestructura , Anticuerpos Anti-VIH/análisis , Humanos , Immunoblotting , Microscopía Electrónica/métodos , Radioinmunoensayo/métodos , Linfocitos T/microbiología , Linfocitos T/ultraestructura , Virión/ultraestructura , Cultivo de VirusRESUMEN
A fragment of HTLV-IIIB gag-gene, coding for the first 441 amino acids of the p53 gag-precursor was expressed in the recombinant vaccinia virus, vC5. Two HIV specific proteins were detected by western blot in CV-1 cells infected with vC5. Their relative molecular masses were 50 and 35 Kd, pointing out that the first of the proteins is a full length expression product of the cloned sequence, while the second one is a result of processing or abortive translation. Possibilities of using such a strain as a vaccine or in Western blot conformation test are discussed.
Asunto(s)
Regulación de la Expresión Génica , Genes Virales , VIH/genética , Proteínas de los Retroviridae/genética , Virus Vaccinia/genética , Productos del Gen gag , VIH/inmunología , Antígenos VIH/genética , Plásmidos , Recombinación GenéticaRESUMEN
The analysis of the DNA of one nontoxigenic C. diphtheriae phage and two toxigenic ones has revealed that phage phi 984tox+ belongs to omega-like tox+ phages, phage phi 9tox+ is a representative of a new group of phages and phage B (Freeman) tox is a deletion mutant of phage beta. The location of this deletion on the physical map of this phage has been established. To obtain the physical map of phage phi 984tox+, the complete library of internal DNA fragments has been constructed in vector pBR 322. The gene of native diphtheria toxin has been cloned in vectors pBR 322 and pUR 250. Plasmids pUR 250 with the inserts of the toxin gene have been shown to be unstable if tox and lac promoters are located in tandem before the body of the toxin gene. The prolonged cultivation of clones having such structure leads to the formation of a spontaneous mutation located in the region coding the C-end part of the A-fragment of the toxin.
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Bacteriófagos/genética , Clonación Molecular/métodos , ADN Viral/genética , Toxina Diftérica/genética , Genes Virales , Deleción Cromosómica , Corynebacterium diphtheriae , Toxina Diftérica/biosíntesis , Escherichia coli/genética , Vectores Genéticos , Plásmidos , Mapeo RestrictivoRESUMEN
An enzyme immune diagnosticum for the detection of the antigen and antibody to human immunodeficiency virus (HIV) has been developed at D. I. Ivanovskii Institute of Virology of the USSR AMS. The method is based on the principle of competitive analysis using an antiviral conjugate which allows the sera to be tested without preliminary dilution and ensures a high sensitivity of the diagnosticum. The survey for HIV antibody covered 5743 subjects, among them 4898 Soviet citizens predominantly belonging to high risk groups of contracting AIDS infection, and 845 foreigners. No antibody to HIV has been detected in any of the Soviet citizens. Among the foreigners, antibody to HIV were detected in 6 subjects, all of them arriving from different African countries.
Asunto(s)
Serodiagnóstico del SIDA/métodos , Síndrome de Inmunodeficiencia Adquirida/prevención & control , Anticuerpos Anti-VIH/análisis , Antígenos VIH/análisis , Tamizaje Masivo/métodos , África/etnología , Estudios de Evaluación como Asunto , Humanos , Técnicas para Inmunoenzimas , Juego de Reactivos para Diagnóstico , Factores de Riesgo , U.R.S.S.RESUMEN
The results of HIV virus isolation from patient A. T., resident of Central Africa, are discussed, in whom Kaposi sarcoma was diagnosed clinically and histologically, and immunological examinations revealed the acquired immunodeficiency syndrome (AIDS). Cocultivation of the peripheral blood leukocytes of the patient with normal donor leukocytes yielded a leukocyte culture in which HIV virus expression was demonstrated. The HIV antigen was detected in the ultracentrifugate of the cultures by means of indirect enzyme-immunoassay using sera to the virus from the standard kits of Organon (Netherlands) and Abbot (USA). HIV antigen was also detected on the surface of lymphocytes in the culture by indirect immunofluorescence using the same sera. Besides, reverse transcriptase activity was demonstrated in ultracentrifugates of the culture fluid by exogenous reverse transcription test using poly(zA)-oligo(dT) matrix.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/microbiología , VIH/aislamiento & purificación , Linfocitos/microbiología , Sarcoma de Kaposi/microbiología , Adulto , África Central , Anticuerpos Antivirales/análisis , Antígenos Virales/análisis , Células Cultivadas , Técnica del Anticuerpo Fluorescente , VIH/inmunología , Humanos , Técnicas para Inmunoenzimas , Masculino , ADN Polimerasa Dirigida por ARN/análisis , UltracentrifugaciónRESUMEN
The possibility of optimizing the conditions for the cultivation of cells producing human immunodeficiency virus (HIV) was explored. The stimulating effect on the cell cultures of interleukin-2 and specific anti-interferon antibodies was examined. The individual use of interleukin-2 or anti-interferon antibody preparations did not result in any marked enhancement of HIV virus reproduction in the cells, whereas combining of interleukin-2 which stimulated proliferation of T-lymphocytes with poly- and monoclonal anti-interferon antibodies proved to be effective increasing the expression of virus-specific antigens in the cells 1.5-fold. It seems expedient to carry out further screening of different reagents and combinations thereof capable of significantly increasing HIV virus reproduction in cell cultures which would serve as the antigen for diagnostic systems.
Asunto(s)
Fibroblastos/microbiología , VIH/crecimiento & desarrollo , Linfocitos/microbiología , Anticuerpos/análisis , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos , Línea Celular , Fibroblastos/efectos de los fármacos , Fibroblastos/inmunología , VIH/inmunología , Humanos , Interferones/inmunología , Interleucina-2/farmacología , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Estimulación Química , Cultivo de Virus/métodos , Replicación Viral/efectos de los fármacosRESUMEN
A technological scheme has been developed for purification of recombinant antigen of surface protein (ASP) of the causative virus of AIDS from Escherichia coli cells carrying plasmid pL2 which codes for the synthesis of a hybrid polypeptide consisting of phage lambda N protein (59 amino acid residues) and a fragment of SP (env) of HIV virus (569 a.r.). Purification of ASP is based on two separation principles: fractionation of polypeptides of bacterial lysates by preparative isoelectrofocusing in a granulated gel layer and the method of preparative polyacrylamide gel electrophoresis in "Multiphor" apparatus (Pharmacia). The ASP purified by these methods was used for construction of an immunodiagnostic preparation for AIDS, employing for this purpose solid-phase enzyme-immunoassay in two modifications: competitive sandwich method and analysis of the tested sera with direct sorption of ASP on nitrocellulose filters.