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Situation and main characteristics of the AIDS epidemics in Romania are analysed. Prevention measures, among which it is worth mentioning a correct information of the population, are proposed.

The antiviral effect of human interferons alpha and beta was inhibited in dose-dependent manner by submillimolar concentrations of neomycin, known to block phosphoinositide hydrolysis and therefore the diacylglycerol formation. On the contrary, the synthetic permeant diacylglycerols (1-oleoyl-2-acetyl-sn or rac-glycerol) were able to induce an interferon-like antiviral state when tested against the vesicular stomatitis virus and herpes simplex type I virus. Hidaka's compound H-8 (1.2 μM), expected to inhibit cAMP- and cGMP-dependent protein kinases, did not modify the antiviral effect of interferon. Our data suggest that the phosphoinositide pathway is involved in transducing the interferon antiviral signal, but, since the exogenous phospholipase C (0.1 – 1 U/ml) failed to induce an antiviral state, this pathway, although implicated, seems not the only one.

At high in vitro passage levels HSV-2-transformed hamster and rat cell lines were oncogenic for the homologous animals, inducing fusocellular or round-cell sarcomas. The cell lines obtained by in vitro cultivation of the tumors were free of infectious virus.

The results obtained at the Dermatological service of the Colentina Hospital show that the product NIVCRISOL-D, containing propolis, has a significant therapeutical effect against recurrent herpes and zona zoster.

Complement fixation (CF) and passive hemagglutination (PHA) tests (the latter with a M. pneumoniae antigen coupled by glutaraldehyde onto red blood cells) were performed in 263 patients with various infectious diseases (mostly in the 1st and 2nd week after onset) and non-infectious ones. CF reaction proved to be inappropriate for the early etiological diagnosis of mycoplasma infections, since the high titers were distributed undifferentially among the various patient groups and many sera (38%) showed anticomplementary activity. A PHA titer of at least 1/128 (preferably of 1/512) points to the presence of a M. pneumoniae infection, especially if clinical, radiological and laboratory data suggest a nonbacterial or mixed pneumonia. The diagnosis is often early enough to orientate the etiological therapy towards macrolides and tetracyclines. The PHA reaction recommended is specific, sensitive, reproducible and easy to perform.

Native and purified HBsAg preparations were subjected in vitro to the action of cetylpyridinium bromide (Bromocet), hibitan-chlorhexidine (Hibiscrub), chloramine B and propolis extract, at different concentrations and for various time intervals. The effect of these agents on the serological reactivity of HBsAg was tested by electroimmunodiffusion (EID) and radioimmunoassay (RIA). Chloramine B and the propolis extract had a significant inhibitory effect-ascertained by both EID and RIA - on purified HBsAg, but not on the native preparation. The inhibition exerted by Bromocet and Hibiscrub indicated by EID results was not confirmed by RIA.

Persistent infection with measles virus established in a calf kidney cell line differed in some features from other measles virus carrier systems. After a variable life span, ranging from 50 to 1100 days, six of the chronically infected cell lines showed an evolution towards lytic infection. Only one of these lines, the K-2 cell line, exhibited marked morphological, growth and chromosomal alterations suggesting in vitro cellular transformation. The transformed K-2 cells released infectious measles virus with several modified biological parameters. Persistent infection was not due to the accumulation of thermosensitive mutants or defective particles. The role of the host-cell factor and of the selection of the virus population during its passage in RV cells are discussed.

The cell growth inhibitory action of rat interferon (IFN) was investigated in two systems: a cell line obtained by transformation of rat embryo fibroblasts under the action of a ts mutant of herpes simplex virus and a tumor cell line derived from tumors induced in rats by transformed cells. The growth inhibitory effect of IFN, evaluated by cell counting and colony formation in soft agar medium, was dependent on the exponential cell growth rate and on the concentration of IFN in the medium. Long-time subcultivation of the two cell lines in the presence of IFN did not result in the selection of a cell population resistant to the growth inhibitory effect of IFN, but led to a decrease in the oncogenic potency of the tumor cell line.

The presence of ceruloplasmin in the inoculum inhibits the multiplication of influenza virus A/PR8/34 (H0N1) in chorioallantoic membrane fragments. Virus corpuscles that remain uncoupled to ceruloplasmin infect the host cells and their replication results in progens whose properties differ from those of controls inoculated in the absence of ceruloplasmin. The variation in time of the characteristics of the respective virus progens is discussed.

Attempts have been made to culture mononuclear cells from synovial fluid of 8 patients with arthropathy, and have led to the development of the lymphoid cell line IVPat-88. Cell line has been propagated by serial passages for more than 14 weeks in continuous culture. The cells grew as single, free-floating individuals, or in dense clumps without adherence to glass or plastic surface. All these cells were identified as altered lymphoblasts because of their growth pattern and uniform morphology, and the presence of Epstein-Barr Viral Capsid Antigen (VCA) in 5 to 10% of the cells. The cell concentration varied during the period of culture from about 300,000 to 1,700,000 cells per ml, and mean doubling time during phases of active growth was 42 and 60 hours in MEM and RPMI 1640 tissue culture media, respectively. The methods used and the characteristics of the cell line are described.

Multilamellar and unilamellar phospholipid liposomes were prepared and investigated as regards their properties and the capacity of encapsulating biologically active materials, such as CrO4-(2-)ions, basic dyes, proteins, DNA, as well as Sendai virus particles. The efficiency of encapsulation ranged from 10% for CrO4-(2-)ions to about 80% for toluidine blue; it was found to depend not only on the type of encapsulated material, but also on the method used for liposome preparation and on liposome composition.

A number of 632 new cases of subacute sclerosing panencephalitis (SSPE) could be detected during a 10-year survey. The continuous increase in the number of annual cases suggests a possible correlation with the changes induced in measles epidemiology by the initiation of compulsory vaccination. On the other hand, a comparison of epidemiological and serological characteristics revealed significant differences between the series of SSPE cases recorded in the period preceding and in that following measles vaccination.

As evaluated by light scattering at 90 degrees, natural organic oligocations such as putrescine, spermidine and spermine interfered with myxovirus aggregates which were induced by the histone H2A and strongly amplified by shaking during incubation. In contrast, the synthetic oligocation 1.7-diamino heptane itself aggregated the virus particles, its action being unmodified by adding polycationic H2A in abundance. When human chromosome preparations treated with protamine solution and shaked during incubation were covered with a stable polycationic molecular layer, the chromosomes had become unstainable by the Giemsa method even if the dye was used in excess. Nevertheless, the affinity of influenza virus particles for protamine was so high that they were able to dissociate the protamine molecules from the preformed complexes reconstituting the affinity of chromosome preparations to Giemsa stain. The virus-caused shift in the staining ability of chromosomes did not occur when bacterial suspension was added instead of the viral one. The model of oligocationic relaxation and of polycation condensation accounting for the modulatory effects of polyamines is discussed.

Ceruloplasmin administered in different variants confers on mice protection against experimental infection with influenza virus APR 8/34 (H0N1). The optimal variants are: inoculation of an extemporaneous virus-ceruloplasmin mixture, followed by two additional ceruloplasmin applications (which confers maximum protection against initial infection) and the administration of ceruloplasmin prior to virus inoculation (which assures the highest resistance to challenge infection).

Introduction. Principles of the Modern Diagnosis in Virology--isolation of the causative agent;--histologic and electronoptical diagnosis;--serologic. Efficiency of the viral diagnosis. Modern and Rapid Diagnostic Methods--progress in the technology of cell cultures and immunofluorescence;--new serologic methods.

The authors discuss different aspects of the rapid diagnosis of viral infections: its necessity, its characteristics, the recent advances having allowed the development of modern techniques. Further, the main categories of procedures used in rapid viral diagnosis are reviewed: 1) electron microscopy, 2) immunofluorescence and immunoperoxidase techniques; 3) solid-phase systems with labelled reactants; 4) agglutination with supporting particles; 5) counterimmunoelectrophoresis; 6) rapid/early serological diagnosis. Data are discussed as regards the possibility of the large-scale application of rapid viral diagnosis procedures in Romania.

The biological characteristics of a measles virus strain (Co-69/pi) isolated from a selected chronically infected calf kidney cell line (K-2) are studied in comparison with those of thw wild parental CO-69 and of the attenuated Schwarz measles virus strain. Co-69/pi is a variant of the parental Co-69 virus and has characteristics of an attenuated strain. Some of the characteristics acquired by the Co-69/pi strain (cytopathogenicity, size of plaques) proved to be stable in the course of passages on a simian substrate. The mechanism having led to the appearance of this variant in the chronically infected cell line are discussed.

The results obtained in the "Stefan S. Nicolau" Institute of Virology by the study of herpes simplex virus (HSV) are reviewed. The investigations were mainly focused on HSV biology, genetic markers, experimental HSV infection, correlation between HSV and some diseases, action of some chemical and biological preparations on HSV, in vitro and in vivo HSV oncogenicity, HSV-induced surface antigens, a.o.

The protection conferred by the inactivated influenza vaccine Nivgrip against influenza caused by the A(H3N2) virus was demonstrated in three school communities of a large urban centre during the epidemic outbreaks occurring in the winter season of 1983. The specific protection was reflected by the lower morbidity by influenza-like respiratory infections and by the absence or scarcity of postinfluenza complications in vaccinees.

Natural macromolecular polycations (protamine, histones H1, H2A, H2B and H3) caused the clustering of influenza and parainfluenza viruses into aggregates heterogeneous in size, as well as a decrease in their hemagglutinating capacity. Polycation-induced virus alterations consisted in surface pyknosis and an increase most efficient as regards the interaction with viruses.

Prospective and retrospective statistical studies were performed in 1,000 cases of congenital malformations. The incidences and severity of the different types of malformations were correlated with the risk and protection factors having acted on the pregnant woman. The correlation coefficients were higher in the case of specific risk factors, among which special attention was paid to maternal virus infections. The possibility is discussed of developing a programme for the individual protection of high-risk cases, implying the compensation of the exposure to risk factors by the application of adequate protection factors, according to the calculated scores.

Surface antigens induced by herpes simplex virus infection in HeLa cells remain unaltered after treatment of the cells with 2% formalin for 10 min or with 0.08% trypsin for 15 min at 37 degrees C. A longer trypsin treatment (for 1 hour) will cause gradual alterations in the virus-induced antigens. Hence, these antigens are proteins deeply implanted within the cellular membrane. Their mobility--optimal at 37 degrees C--allows aggregation of the antigens in the form of caps or patches by polyvalent ligands such as IgG.

Sera collected from several migratory birds of the Danube Delta, from humans and domestic birds and animals of three Romanian counties were tested by hemagglutination-inhibition reaction for the presence of antibodies to Yaba 1--Lednice 110 virus. Antibodies could be detected in only 8 of the 14 species of migratory birds included in the study, especially in wild geese and ducks.

Preincubation of Sendai virus with ceruloplasmin induced in chorioallantoic membrane (CAM) fragments the synthesis of a population with decreased infectivity and high haemagglutinating (HA) and neuraminidase (NA) activities, whereas preincubation with solubilized virus envelopes led to the production of a viral population with the same infectivity as the control, but with lower HA and NA activities. Preincubation of the virus with a mixture of ceruloplasmin and solubilized envelopes depressed the overall virus synthesis; the resulting population had a low infectivity and high HA and NA activities. The variation in the HA/NA ratio indicates a modification in the envelope structure.

A mathematical methodology is suggested which allows the a priori calculation of the risk of premature delivery, by a formula relying on the scores attributed to different specific risk factors (maternal virus infections included). The scores are estimated either directly, or starting from the scores of nonspecific factors. The statistical significance of the different scores, correlations and formulas is analyzed.

The presence of interferon and type A immunoglobulins (IgA) was followed up in the nasopharyngeal washings collected from volunteers immunized intranasally with an inactivated influenza vaccine [strain A/Rom 1/73 (H3N2)]. Interferon was detected 24 hours after vaccine administration, its incidence being similar to that in the course of acute infection. Intranasal administration of inactivated influenza vaccine stimulated the production of secretory IgA in 3 of 10 samples collected 12 days after vaccination. At the same time, IgA were found in 4 samples collected before vaccination, and inhibited in certain cases the stimulation of interferon synthesis. The practical importance of the route of influenza vaccine administration is discussed.

Sendai virus multiplication in the presence of ceruloplasmin resulted in the appearance of qualitatively modified progens. There was an increase in the proportion of incomplete virus particles and a decrease in hemagglutinin and neuraminidase activities, in virus infectivity and antigenicity (with the exception of subviral fractions with predominant hemagglutinating activity). Virus progens obtained in the presence of ceruloplasmin had a higher sensitivity to detergent treatment; virus ghosts formed by re-aggregation of envelope fragments could be observed in the electron microscope.

Multiplication of influenza virus A/PR8/34 (H1N1) in the presence of either ceruloplasmin or parainfluenza type I (Sendai) virus results in the appearance of progens different from the parental virus as regards some of their biological properties. The role of viral envelope changes in acquiring new characteristics is discussed.

Transformation of rat embryo fibroblast was induced by a temperature-sensitive mutant of herpes simplex virus type 2. Transformation was scored using the morphological criterion of focus formation and the cell changes that lead to the final focus are described. Virus genome persistence in the transformed cell line was demonstrated by the presence of virus-specific membrane antigens and by the specificity of antibodies elicited in rabbits by inoculation of transformed cells. The cytogenetic analysis of the transformed cells revealed changes in chromosome number and the presence of marker chromosomes.

Essential peculiarities of the kinetics of the morbidity evolution of most frequent virus diseases were explained using a determinant mathematical model. The main epidemiological parameters for the whole territory of the S.R. of Romania and of Sibiu County were evaluated for the 1967-1986 period.

Guinea pigs were inoculated intracerebrally with cerebrospinal fluid (CSF) and/or brain tissue suspensions from 8 patients with Creutzfeldt-Jakob disease (CJD) and with CSF from 2 patients with Alzheimer's disease. After a very long incubation period (over 360-420 days) a serially transmissible experimental disease appeared in the guinea pigs inoculated with CSF from 5 of the CJD patients, with either CSF or brain suspension from one CJD patient and with brain suspensions from the remaining 2 CJD patients. The disease was characterized by tremor, ataxia, convulsions and morphopathological lesions, such as spongiform change, glial hyperplasia and vacuolation of the neurons. Inoculations of CSF from the two Alzheimer's disease cases gave negative results.

Anti-albumin antibodies previously described by different authors in viral hepatitis were also investigated in patients with other diseases. Significant titers of such antibodies could be detected -- by passive hemagglutination reactions using a system of bovine serum albumin-coated sheep red blood cells and human sera -- not only in viral hepatitis, but also in infectious mononucleosis cases and in patients with different forms of cancer. Onto-phylogenetic considerations on the significance of these antibodies for different stages of the process of cell de-differentiation or for disorders of intercellular contacts under the action of some viral agents are discussed.