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Concentration of organochlorine pesticides (OCPs) (α-, ß-, γ- hexachlorocyclohexane (HCH), dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethane (DDD), dichlorodiphenyldichloroethylene (DDE)) in four species of Pacific salmon (pink, chum, chinook, and sockeye) are presented. OCPs in salmon organs increased in the following order: muscle < liver < eggs < male gonads. Concentrations of the OCP in salmon organs increased in following order: DDE < γ-HCH < α-HCH. The level of pollutants in salmon is compared with the sanitary and epidemiological norms of Russia and other countries. Cancer and noncancer hazard ratios through consumption of salmon in Russian Far East for both men and women also were summarized. Noncancer and cancer hazard ratio values were far below threshold values (<1.0).

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The article presents statistics concerning demographic "crisis" in the regions of Chernigiv area and in Ukraine, as a whole with connection to consequences resulted from Chernobyl catastrophe. The crisis is characterized by increase in population mortality and birth rate reduction, that caused negative natural growth tendency of population. The factors causing reduction in population number of Chernigiv Oblast and in Ukraine as a whole are the following: the effect of ionizing radiation, social-economic indices (the reduction of population profits, unemployment, worsening of medical care, psychoemotional stress caused by the crisis situation in Ukraine, migration of the considerable number of population abroad).

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BACKGROUND & AIMS: Plasmid DNA-based immunization has been shown to be an effective means of vaccination in animal models. In this study, the immune responses to various hepatitis C virus structural protein antigens were evaluated using this technique. METHODS: Six recombinant plasmids were constructed. These include, individually, the coding regions for the core protein (pC); E1 (pE1) and E2 (pE2); as well as core, E1, and E2 together (pCE1E2); E1 and E2 together (pE1E2); and finally an E2 construct from which the N-terminal hypervariable region had been deleted (pE2 deltaHVR). These plasmids were transfected into mammalian cells to test their protein expression and were injected into the quadriceps muscles of BALB/c mice to measure specific antibodies and cytotoxic T-lymphocyte responses. RESULTS: All the recombinant plasmids were shown to express specific antigens transiently in cells and elicited specific antibody responses to core, E1, and E2 in mice. Specific cytotoxic T lymphocyte responses were detected only in mice injected with plasmid constructs encoding the core. CONCLUSIONS: Genetic immunization can aid the development of hepatitis C virus vaccines by allowing for the rapid construction and evaluation of different expression plasmids as potential immunogens.

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Negative strands of the hepatitis C virus (HCV) genome (a positive-stranded RNA virus) have been found in a nuclease-resistant form in the serum of patients with HCV infections. We determined whether a complete negative-strand copy is present in the serum, whether the negative strand is particle-associated, and finally, whether it is virion-associated and encapsidated like the positive (genomic) strand. Isopyknic sucrose and cesium chloride density ultracentrifugation followed by a strand-specific reverse transcription-polymerase chain reaction on the collected fractions was performed to determine whether both positive and negative strands were associated with similar particles. Both strands comigrated to approximately the same density (1.11-1.16 g/cm3) in sucrose. After treatment of the plasma with detergent (0.1% Nonidet P-40) to remove the viral envelope and centrifugation on cesium chloride gradients, the positive strands shifted to a density of 1.35 g/cm3, and the negative strands were not detected. By using antibodies specific for the HCV core or envelope glycoproteins E1 or E2 coated onto the wells of a microtiter plate, it was possible to specifically bind HCV or viral cores to the solid phase. Pelleted virus particles were resuspended in either PBS or PBS with 0.1% Nonidet P-40 to expose the core. These pellets were then incubated in antibody-coated microtiter wells. RNA extracted from the bound and unbound fractions was tested for HCV RNA. The anti-core antibody was able to bind positive strands but not negative strands only in detergent-treated samples. In the nondetergent-treated pellets, the anti-E1 and -E2 bound the positive strand, but only anti-E1 bound the negative strands. These findings indicate that while both strands of HCV RNA can be detected in serum, the positive strand is encapsidated within the enveloped core, and the negative strand appears to be in a membrane particle associated with the viral envelope protein E1 but does not appear to be within the HCV core of circulating virions.

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OBJECTIVE: To determine whether liver transplantation and the subsequent immunosuppression affect the antibody response to hepatitis C virus (HCV) infection. METHODS: Sera from 46 patients were compared before and after liver transplantation for markers of HCV infection. Serum HCV RNA was determined by polymerase chain reaction (PCR). Anti-HCV antibody was determined by first- and second-generation immunoassays as well as a quantitative assay of the titer of anti-HCV core antibody. RESULTS: Among individuals who acquired hepatitis C infection in association with liver transplantation, only 15% (3/12) developed antibody to the core antigen and only 25% (3/12) reacted to any antigen present on the second-generation recombinant immunoblot assay after a mean follow-up period of 18 months. Thirty-eight percent (5/13) were positive, by the second-generation enzyme immunoassay (EIA-2) Whereas 94% (16/17) of the individuals who had detectable anti-HCV core antibodies pretransplant continued to have such antibodies after transplant, the titer of these antibodies declined an average of 4-fold. No significant change was seen in the antibody titer toward rotavirus, a common viral pathogen. Patients who acquired HCV infection or in whom the allograft became reinfected had a significantly increased incidence of posttransplant hepatitis (61% vs. 33%, respectively). CONCLUSIONS: Liver transplantation and posttransplant immunosuppression lead to an attenuated antibody response to hepatitis C viral infection. Currently available assays for anti-HCV antibodies may be unreliable in the posttransplant setting.

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Four monospecific antibodies against the hepatitis C virus nucleocapsid protein, which was expressed by recombinant baculovirus, were obtained by Epstein-Barr virus transformation of B cells from three patients with chronic hepatitis C virus infection. One of these antibodies was IgG and the other three were IgM. Their specificities were characterized initially by enzyme-linked immunosorbent assay and immunoblotting against hepatitis C virus proteins expressed by six recombinant baculoviruses with different hepatitis C virus sequence insertions. These specificities were confirmed, and their epitopes were more precisely determined with a series of overlapping decapeptides made by solid-phase pin technology. Two antibodies (1F4 and 2G6) reacted with the same peptides located near the amino(N)-terminus of nucleocapsid protein (amino acids 33-50). The third antibody (3B5) recognized the peptide consisting of amino acids 133-142, and the fourth antibody (3B9) was mapped to the carboxy(C)-terminus and reacted with a peptide consisting of amino acids 165-174. This epitope has not previously been reported. Two antibodies, 1F4 and 3B9, which are specific to the N-terminus and C-terminus of nucleocapsid protein, respectively, have been stably produced for more than 6 mo and are being subcloned to establish monoclonality. These antibodies should be useful reagents for the study of hepatitis C virus.

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We cloned and expressed the sequences encoding the structural proteins of the hepatitis C virus in a baculovirus eukaryotic expression system. Four recombinant constructs expressed sufficient hepatitis C virus-specific proteins in insect cell culture to allow analysis of protein cleavage, glycosylation and immunoreactivity. Using immunoblot analysis, we detected a 22-kD protein corresponding to the hepatitis C virus capsid protein cleaved from a larger precursor. Recombinant constructs encoding the presumptive envelope (E1) protein produced products ranging from 30 to 35 kD, whereas constructs encoding the presumptive E2/NS1 protein expressed products ranging in size from 68 to 73 kD. The recombinant envelope proteins were glycosylated, as shown by sensitivity to endoglycosidase F digestion, whereas the capsid was not. We examined the immunoreactivity of these recombinant proteins using sera from 50 patients chronically infected with HCV. Forty-seven of 50 of these sera contained antibodies against the capsid, 14 (28%) also had antibodies against E1 and at least 5 (10%) had antibody against E2/NS1. Forty-seven of 50 sera (94%) were viremic, as determined on hepatitis C virus polymerase chain reaction. The three sera that were hepatitis C virus polymerase chain reaction negative did not have envelope antibodies, whereas all sera that had envelope antibodies were also hepatitis C virus polymerase chain reaction positive. Thus antibodies to baculovirus-expressed hepatitis C virus structural proteins, including E1 and E2/NS1, are found in the presence of viremia.

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Three alternatively spliced forms of the amyloid precursor protein (APP), APP-695, APP-751, and APP-770, were expressed in the baculovirus expression vector system. The recombinant proteins were secreted into the culture medium by infected insect cells, and APP molecules were detected in insect cells and medium 2 days after infection with the recombinant APP-baculoviruses. A partial sequence of the NH2 terminus of the secreted protein revealed identity with the native secreted protein and showed that the signal peptide was recognized and properly cleaved in insect cells. Purified secreted recombinant APP-751 comigrated with protease nexin 2 purified from platelets and fibroblasts. A 15-kDa COOH-terminal fragment of APP was also detected in cells infected with recombinant baculoviruses, suggesting that recombinant APP proteins were cleaved at the COOH-terminal end like native APP protein. Recombinant APP-751 and APP-770 formed complexes with epidermal growth factor-binding protein, whereas APP-695 did not. In addition, recombinant APP-751 and APP-770 inhibited trypsin and chymotrypsin activity, whereas APP-695 did not. Growth of a human fibroblast cell line, A-1, that required APP for complete growth, was restored upon addition of secreted recombinant APP-695 or APP-751. Thus, the appropriately sized, secreted recombinant APP proteins produced in this expression system are biologically active.

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The results of the controlled field trial of lyophilized erythrocytic immunoglobulin diagnosticum for the detection of hepatitis A virus antigen in the urine and feces of patients are presented. This diagnosticum was used for the study of urine and fecal samples from 225 patients (of these, 176 had hepatitis A) and 54 healthy persons in the passive hemagglutination (PHA) test. Their blood sera were studied in the PHA test (to detect HBsAg) and the radioimmunoassay (to detect anti-HAV IgM). The immunoglobulin diagnosticum under study was found to be nonspecific and faintly sensitive and, therefore, unsuitable for use in medical practice.

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A modified enzyme immunoassay based on adsorption of antihepatitis A virus (HAV) IgG-HRPO conjugate and monoclonal antibodies to HAV were used to investigate antigenic differences between mature HAV virions and subviral particles with different buoyant densities in CsCl produced in HAV-infected cells. The mature virions (1.34 g/cm3) appeared to have common antigenic determinants with subviral particles (1.20, 1.27, and 1.30 g/cm3) and possess some additional determinants. Nevertheless, both subviral particles and mature virions induced antibodies capable of neutralizing HAV infectivity in tissue culture.

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The results of examinations of sera from apparently normal urban and rural residents of the Guinea Republic (GR) for markers of viral hepatitis A (anti-HAV) and B (HBsAg) are presented. The number of HBsAg-positive subjects was 16 +/- 1% (1199 serum specimens were examined by direct enzyme immunoassay, EIA, and HI test), the rate of HBsAg findings in sera from children (less than 16 years) and adults (greater than or equal to 16) did not differ significantly (p less than 0.05). The rate of a HBsAg carrier state did not depend on sex and residence of the subjects under study (p less than 0.05). The detection rate of total (IgM + IgG) anti-HAV antibody was 67 +/- 2% (812 serum specimens were examined by a variant of EIA block). The detection rate and titres of anti-HAV in children were higher than in adults, and in urban residents higher than in rural subjects (p less than 0.05). The results of detection of HBsAg and total anti-HAV antibody in the sera of GR residents are close to those obtained in examinations of sera from the populations of countries bordering GR in Western Africa (Senegal, Mali, Liberia) and are typical of Africa as a whole.

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Specimens from patients with gastroenteritis (GE) collected during outbreaks and from sporadic cases reported in the USSR in 1979-1984 were examined by electron microscopy (EM), enzyme immunoassay, rotavirus neutralization test in cell culture. All the winter-spring outbreaks and a considerable number (34.9%) of sporadic GE cases were caused by rotaviruses. The summer-autumn outbreaks were of non-rotavirus nature. In water-borne winter-spring outbreaks in adults, severe forms of GE with signs of dehydration were observed. Among infants, cases of virus-carrier state were detected. The rate of rotavirus detection by EM in winter-spring outbreaks depended on the time of specimen collection and decreased after 4 days from the onset of the disease. Apart from rotaviruses, adeno-, astro-, calici-, coronaviruses, and picornavirus-like particles were detected by EM in feces from GE patients.

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The authors have studied the effectiveness of the first Soviet test system for the diagnosis of hepatitis A by means of the enzyme immunoassay (Diagn-A-Hep), developed at the Institute of Poliomyelitis and Viral Encephalitides, Moscow, under the conditions of different epidemic situations. In the process of this trial the high specificity and sensitivity of this test system, established earlier in the certification and commission trials, have been confirmed. Diagn-A-Hep has proved to be highly effective in the diagnosis of acute forms of hepatitis A and permitted its detection in patients during the incubation period, as well as in patients with anicteric and asymptomatic subclinical forms. Besides clinical diagnosis, the kit Diagn-A-Hep may be used in large-scale seroepidemiological surveys of the immune structure of the population, as well as in detection of HAV in different material under test.

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The materials presented in the paper are first indications of the pathogenicity of Dhori virus for man and prove the role of this agent in the occurrence of 5 cases of the disease in laboratory workers accidentally infected during the preparation of cultural agents. Clinically, Dhori infection was characterized by an acute course with marked general toxicity and a febrile period of 2 to 4 days. Two out of 5 patients had changes on the part of the nervous system of the type of encephalitic reaction predominantly with subcortical symptoms and mild involvement of the pyramidal system or in the form of encephalopolyradiculoneuritis with paresthesia and sensitivity disorders.

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A new test system Diagn-A-Hep for the laboratory diagnosis of hepatitis A (HA) by means of the enzyme immunoassay has been developed at the Institute of Poliomyelitis and Viral Encephalitides (Moscow). The sensitivity and specificity of the newly developed test system have proved to be similar to those of the well-known commercial diagnostic system HAVAB manufactured by Abbott Laboratories (USA). Diagn-A-Hep permits the diagnosis of HA with 96-100% effectiveness both in patients with the acute form of the disease and in patients with its anicteric or inapparent forms. This system is simple and convenient, it may be employed in inadequately equipped laboratories or even under field conditions. The rules for the selection of immunobiological preparations to be included in the test system have been worked out.

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Growth characteristics of the HAS-15 strain of human hepatitis A virus (HAV) in rhesus monkey foetal kidney cell line (FRhK-4) are described. The conditions optimal for the accumulation of infectious HAV and viral antigen (HAAg) in the infected cells and tissue culture fluids were studied. The production of infectious HAV occurred in the first stage while in the second stage predominantly HAAg was accumulating intracellularly. Serological properties of the cultivated HAV proved to be very similar to those of the HAV occurring in hepatitis A patients.

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Physicochemical characteristics (sedimentation coefficient, buoyant density of particles, as well as ribonuclein of these particles) and morphology of the causative agent of hemorrhagic fever with renal syndrome were found to be similar to those of the other members of the Bunyaviridae family.

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