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Biomedical subjects

G Rocchi

Publications and source records attributed to G Rocchi.

At least 109 records · Page 6Linked to original sources

[Antibody response to an anti-influenza vaccine of inactivated whole virus, titrated in micrograms, used in the 1980/81 season].

Antibody response of 68 healthy young-adult volunteers to A/Bangkok/1/79 (H3N2), A/Brazil/11/78 (H1N1), B/Singapore/222/79 trivalent anti-influenza virus vaccine was studied by haemagglutination inhibition and single radial haemolysis techniques. The results of this study indicate that immunogenicity of the individual components of the vaccine (10 micrograms each) varied significantly, the highest frequence of antibody response occurring for A/Brazil influenza virus strain and the lowest for B/Singapore.

Adult↗

Single radial haemolysis for rubella antibody screening.

The single radial haemolysis technique was employed for the detection of rubella antibodies. By using this technique, as compared with the conventional haemagglutination-inhibition test on the same serum samples, it was observed that the single radial haemolysis technique supplies a reliable method for large rubella antibody screening.

Antibodies, Viral↗

[Seroepidemiology of rubella in Rome (1972-1978)].

Data on hemoagglutination inhibition (HI) tests for rubella immunity which were performed in our laboratory since 1972, are reported. The results obtained on sera from healthy young women indicate a significant decrease of incidence of sero-negatives in 1978 as compared with previous years. The incidence of high titer-positive sera and the geometric mean titer of HI antibody were significantly greater in 1973 and 1978 than in the remaining years; a greater number of case reports to Public Health Authorities occurred in Rome during these two years. The data are also discussed in relationship with vaccination program.

Antibodies, Viral↗

Antibody reactive in antibody-dependent cell-mediated cytotoxicity following influenza virus vaccination.

The antibody reactive in antibody-dependent, cell-mediated cytotoxicity (ADCC) to influenza virus-infected cells was measured in two groups of seven volunteers each, before and after immunization with inactivated or live attenuated A/Victoria/3/75 influenza virus vaccines. Age-matched controls were seven adult individuals who experienced natural influenza infection due to A/Victoria/3/75-like virus strain. After inactivated whole influenza virus immunization all the subjects showed a significant rise of the antibody reactive in ADCC (from a mean value of 4.7% to 17.1% cytotoxicity, before and 5 weeks after immunization, respectively) as well as of hemagglutination inhibition (HI) antibody (fourfold or greater increase). These immune responses were similar to those observed among naturally infected controls. After live attenuated virus vaccination, no significant increase in titer of antibody reactive in ADCC was detected, even though the vaccine induced significant increase of HI antibody titer. Little correlation was found between ADCC and HI antibody rises in sera of recipients of inactivated virus vaccine and of naturally infected individuals while, in live attenuated influenza virus vaccines, the rise of HI antibody titer did not correspond to a significant increase of ADCC antibody titer did not show subjects who developed a significant rise in ADCC antibody titer did not show significant variation in antibody to neuraminidase and/or to complement fixation influenza virus antigens.

Adolescent↗

Secretory immune response after nasal vaccination with live attenuated influenza viruses.

Immunoglobulins and virus-specific antibody in nasal secretions were measured in 18 volunteers before and after intra-nasal vaccination with two live-attenuated type A influenza virus strains. Specific serum antibody rises occurred in 14 out of 18 vaccinees; of those, 11 and 10, respectively, showed significant increase of IgA concentration and of virus-specific antibody in nasal secretions collected 2-4 weeks after vaccination. In one case, a volunteer showed appreciable increase of virus neutralizing antibody in nasal secretions without increase of local IgA concentration and of serum HI antibody. This data indicate that administration of live virus vaccines by upper respiratory route confers effective immunity associated with local antibody synthesis.

Adult↗

Protection from natural infection after live influenza virus immunization in an open population.

Live attenuated influenza vaccine containing the recombinant of A/Victoria/3/75 with A/PR/8/34 virus was administered to healthy adults in a field trial aimed at evaluating protection provided by immunization. The study was designed to measure the effect of vaccination on absenteeism from respiratory disease during a natural influenza epidemic. A total of 2115 male employees of the public transport service of Rome volunteered to participate in the trial, 1050 and 1065 receiving vaccine and placebo respectively, in a randomized blind fashion. Vaccination procedure was completed by the end of December 1976. A small-sized outbreak of influenza, due to a viral strain antigenically homologous to the vaccine, occurred during the month of February 1977. Analysis of absenteeism data, classified according to medical certificate, indicated that morbidity from respiratory disease was reduced in vaccinees compared with controls during the epidemic month; the rate of increase of morbidity compared with that of the preceding month was then three times lower in vaccinees than in controls and the difference in absenteeism between the two groups greatly exceeded the ordinary fluctuation that was observed during non-epidemic periods.

Adult↗

Influenza vaccination with live-attenuated and inactivated virus-vaccines during an outbreak of disease.

Immunization procedures with live attenuated and inactivated vaccines were carried out on a group of young recruits at the beginning of an outbreak of infection due to an A/Victoria/3/75-related virus strain, which occurred in February 1977 in a military camp. A retrospective investigation on protection from clinical influenza was then performed in order to investigate whether immunization with live virus vaccines, administered at the beginning of an epidemic, could provide early protection from the disease. In the course of the two weeks following vaccination, laboratory-confirmed clinical influenza cases occurred in 4 subjects among the 110 volunteers of the control group which received placebo, and in 8, 7 and 4 subjects respectively of the 3 groups of about 125 individuals, each of which received one of the following vaccine preparations: (a), live attenuated A/Victoria/3/75 influenza virus oral vaccine, grown on chick embryo kidney culture; (b), live attenuated nasal vaccine, a recombinant of A/Puerto Rico/8/34 with A/Victoria/3/75 virus; and (c), inactivated A/Victoria/3/75 virus intramuscular vaccine. These data do not support the hypothesis that, during an epidemic of infection, early protection from clinical influenza can be achieved through immunization with live attenuated or inactivated influenza virus vaccines, in spite of the high immunizing capability of the vaccine preparations.

Adolescent↗

Excess mortality from influenza in a large urban population, Rome, Italy, 1956--76.

Influenza activity was studied in the Rome population from 1956 to 1976 by analysis of mortality from respiratory causes and from all causes. During cold weather months, type A influenza virus was associated, as a rule, with epidemic excess deaths at two year intervals while type B virus was prevalent twice during isolation data were also compared with epidemic excess mortality during four consecutive years. The evidence obtained indicated that influenza virus isolation alone does not represent a reliable index of epidemic influenza activity in this population. The proportion of deaths attributed to respiratory causes consistently increased in every epidemic, the most pronounced increases occurring during large epidemics. The break-down by age of deaths from respiratory causes in the course of two epidemic periods showed that the percentage distribution of deaths was essentially the same as in non-epidemic periods. This evidence indicates that the same factors influencing the age-related distribution of mortality from respiratory causes during non-epidemic periods, probably affect the fatal outcome of influenza during epidemics.

Absenteeism↗

Quantitative evaluation of Epstein-Barr-virus-infected mononuclear peripheral blood leukocytes in infectious mononucleosis.

We devised a quantitative assay for Epstein-Barr-virus-infected mononuclear leukocytes (virocytes) to determine their prevalence in the blood of patients with acute-phase and convalescent-phase infectious mononucleosis and in healthy Epstein-Barr-virus-seropositive controls. Mononuclear peripheral blood leukocyte suspensions were tested for virus-determined cytoproliferative activity by cocultivation with human cord-cell indicator cultures. The highest levels of virocytes among circulating mononuclear leukocytes were found in the early acute phase of infectious mononucleosis (up to 0.05 per cent). Virocytemia decreased to levels comparable with those of healthy controls (less than 0.00001 per cent) by the third month after onset of infectious mononucleosis. These findings provide a quantitative profile of the course of the infection at cellular level and support existing evidence of the efficiency of immune control mechanisms in limiting Epstein-Barr-virus infection during the course of infectious mononucleosis.

Acute Disease↗

Seroimmunity to polioviruses in an urban population of Italy.

In a seroepidemiological survey on immunity to polioviruses, carried out in Rome, neutralizing antibodies were titrated on 602 serum samples collected from individuals aged from 6 months to 88 years. The geometric mean titres were 25.24, 25.92, and 18.12 for poliovirus types 1, 2, and 3, respectively. The number of seronegative results for each virus strain was very low (</=1.5%). The immune status of the study population could therefore be considered satisfactory. The distribution of antibody reactivity in different age groups was similar for poliovirus types 1 and 3, while for type 2 a significant difference in titres was found between adults and children.

Adolescent↗

Antibodies to Epstein-Barr virus-associated nuclear antigen and to other viral and non-viral antigens in Hodgkin's disease.

Antibody reactivity to Epstein-Barr virus (EBV)-associated nuclear antigen (EBNA) was investigated by means of the anticomplement immunofluorescence technique on sera from patients with Hodgkin's disease (HD) and from appropriate controls. Antibody levels to other EBV-determined antigens, i.e. viral capsid (VCA) and early antigens (EA), and to measles and rubella viruses, to cytomegalovirus (CMV), and to toxoplasma gondii were also measured. The results of anti-EBV antibody titrations demonstrated that anti-VCA, anti-EA and anti-EBNA reactivity was significantly higher in HD patients than in healthy subjects. There was no significant difference between the distribution of high rubella and measles antibody titers in HD and control sera. The GMT and the incidence of high titer anti-CMV and toxoplasma antibodies were greater in HD patients than in controls. The analysis of the data, according to histological subtypes, showed that the condition of lymphocyte depletion was associated in HD patients with the highest anti-EBNA antibody levels and the lymphocyte predominance with the lowest. This pattern seemed to be peculiar for anti-EBV reactivity, since anti-CMV and anti-toxoplasma antibody levels in the lymphocyte-depleted group of patients did not significantly differ from those of controls. No correlation was found between anti-VCA and anti-EBNA in individual sera of HD patients. This observation suggests that different mechanisms are probably responsible in HD for the release of EBV-related antigen from infected cells.

Adolescent↗

Lymphoid cells in infectious mononucleosis classified according to T and B cell markers.

It has been demonstrated that peripheral blood lymphocytes, particularly the "atypical" ones, are predominantly of the T type in infectious mononucleosis (IM). This is based on membrane marker studies (E rosettes, receptor for complement, receptor for Fc fragment of immunoglobulins (Ig), and membrane Ig) and by anti-T lymphocyte serum. On the other hand, lymphoblastoid cell lines derived from IM patients show the characteristics of B lymphocytes. This permits the suppostion that EBV infects B lymphocytes and stimulates them to proliferate. The cell proliferation is unlimited in vitro and is probably controlled in vivo by T cells. The reduction of cellular immunity in vivo, which contrasts with the high number of T cells in peripheral blood, could be explained by the fact that T cells are engaged in the regulation of B cell proliferation.

Animals↗

Longitudinal epidemiological survey on hepatitis B-antigen carriers among institutionalized juvenile diabetics.

An epidemiological study was carried out in a juvenile diabetics institution, in order to determine the incidence and the significance of the hepatitis associated Australia antigen (HBAg) carriers. By means of counterelectrophoresis and CF an average of 15% HBAg-positive individuals was found during the course of the search (June 1970-January 1973). As a rule the carrier state appeared to be longlasting and it was only occasionally associated with symptoms and/or signs of liver involvement. Isolation measures to inhibit spread of serum hepatitis (the hepatitis most associated with HBAg) failed partially to prevent the spread of the HBAg associated agent suggesting that nonparenteral transmission could play a role in the diffusion of the infection.

Adolescent↗