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N Cabau

Publications and source records attributed to N Cabau.

At least 19 recordsLinked to original sources
PubMed1983

[Prospective study of cytomegalovirus infections in 211 children with kidney transplants].

A prospective serologic study was conducted to determine the incidence of primary Cytomegalovirus (CMV) infection after a renal transplant and to evaluate the consequences on the graft. Serologic tests using the indirect hemagglutination technique with CMV-sensitized erythrocytes were performed serially over 6 years in 370 children initially awaiting renal transplantation. 211 children received a graft during the study period. Transplantation was followed by primary CMV infection in 48 (35.3%) of the 136 children with negative serologic tests at the time of the procedure. The percentage of graft failures is identical in the 75 children with positive tests before transplantation and in the 88 children with negative tests before and after transplantation (24 and 23% respectively). Conversely, only 6 (12.5%) graft failures were recorded among the 48 children who experienced primary CMV infection after transplantation. It can be speculated that these results are due to the immunosuppressive effect of CMV infection.

Adolescent↗
PubMed1983

Natural variation of poliovirus neutralization epitopes.

Poliovirus-neutralizing monoclonal antibodies were prepared against type 1, type 2, and type 3 wild laboratory (Mahoney, MEF1, and Saukett) and Sabin vaccine strains. Fifty-five poliovirus laboratory strains and field isolates were assayed by neutralization index test with a panel of homotypic monoclonal antibodies. A total of 27 monoclonal antibodies were used. Two categories of neutralization epitopes were found, i.e., cross-reacting (K), which is present on almost all strains of the same serotype, and strain-specific (V, variable), either wild (VW) or Sabin (VS). Several distinct neutralization epitopes were defined for each of the three poliovirus serotypes in almost every category. The study of antigenic variation of the Sabin type 1 vaccine virus during replication in human intestine showed that the VS neutralization epitope may be lost and even replaced by the VW epitopes of the parental Mahoney virus. A late isolate from a vaccine-fed infant recovered the complete neutralization epitope pattern of the Mahoney strain. Upon in vivo virus replication, a different kind of antigenic variation was also detected in which an epitope lost its function in virus neutralization but kept its antigenic conformation unaltered. Neutralization epitope analysis demonstrated that the presence of VS epitopes on a field isolate suggests the Sabin origin of the strain when the isolate displays the same epitope pattern as the original Sabin virus, or confirms it when the VS epitope(s) is mutually exclusive of VW epitopes. The lack of VS epitopes on a field isolate does not rule out its being of Sabin origin.

Antibodies, Monoclonal↗
PubMed1981

Freeze-dried erythrocytes for an indirect hemagglutination test for detection of cytomegalovirus antibodies.

An indirect hemagglutination test with lyophilized, fixed, tanned, and cytomegalovirus (CMV)-sensitized sheep erythrocytes for the detection of CMV antibodies is reported. To avoid nonspecific hemagglutination, cells were fixed with glutaraldehyde or Formalin directly in whole blood. The lyophilized, CMV-sensitized erythrocytes obtained by this technique were stable up to 9 months at 37 degrees C and retained the same reactivity at fresh, CMV-sensitized cells. Indirect hemagglutination performed with lyophilized, sensitized cells was highly efficient in detecting CMV-antibodies as compared with complement fixation and enzyme immunoassay.

Animals↗
PubMed1981

Determination of type 1 poliovirus subtype classes with neutralizing monoclonal antibodies.

Hybridomas secreting neutralizing monoclonal antibodies (MA) against type 1 poliovirus were developed by fusion of mouse myeloma cells with splenocytes of immunized mice. Strain-specific MA selected for their capacity to neutralize wild (Mahoney) or attenuated (Sabin, LSc 2ab) poliovirus strains were used for identification of field isolates. A simple and reliable neutralization-index-assay was developed and used to test for intratypic serodifferentiation of poliovirus with the selected MA. Three subtype classes of type 1 poliovirus have so far been identified by testing 4 reference strains and 96 field isolates: Mahoney-like, LSc-like, and strains not recognized by either anti-Mahoney or anti-LSc MA. Neutralizing MA proved an excellent tool for unequivocal antigenic characterization of different poliovirus strains.

Animals↗
PubMed1980

[Seroepidemiology of herpesvirus hominis and cytomegalovirus infections in the first 4 years of life (author's transl)].

Two hundred children and their mothers were examined when they were 10 months, 2 years and 4 years of age. Anti-cytomegalovirus, anti-Herpesvirus hominis and anti-rubella virus antibodies were titered. The evolution of antibody titers showed that primary infections with cytomegalovirus and Herpesvirus are especially frequent during the first months of life, and that mothers are the principal source of infection. In the group studied, it appeared that country of origin of the parents was the most important socio-economic factor influencing the frequency of infections in children, based upon the large variations of the serum positivity in mothers.

Algeria↗
PubMed1979

Seroepidemiology of cytomegalovirus infections during the first years of life in urban communities.

Using indirect haemagglutination assay, combined with a collection of blood samples on blotting cards, seroepidemiological surveys of cytomegalovirus infections during early infancy have been done in different populations (French and immigrant) in urban areas. The comparison of CMV antibody status of mothers and their children at 10 months and at 2 years of age enables possible factors of viral transmission to be defined. During the first year of life, seropositive mothers were the only source of infection and they remained the main source during the second year. Socioeconomic class and educational level are determinant factors in the incidence of viral transmission.

Child, Preschool↗
PubMed1978

[Epidemiology of cytomegalovirus infections (author's transl)].

Improvements of serological techniques allow seroepidemiologic surveys of cytomegalovirus infections. Intrauterine contamination is not unfrequent (1%) but pathological consequences of these infections in the fetus had only been observed after primary infections of the mother. Infections in the first days of life are frequent. The mother is almost exclusively the source of contaminations. The frequency of these infections is influenced by socio-economic factors. In adolescents and adults, contaminations seem related to closed person to person transmission (sexual behavior, kissing...).

Adolescent↗
PubMed1977

[Evolution of cytomegalovirus antibodies of maternal origin and acquired, throughout the first year of life (author's transl)].

Cytomegalovirus antibodies have been determined by indirect hemagglutination technique in sera taken during the first year of life in two infant groups : Bantu infants in Mozambique, French infants in Alsace. IgM specific antibodies have been detected in serum fractions obtained by density gradients. The evolutions of maternal antibodies and of antibodies resulting from a primary CMV infection have been documented. The analysis of the results confirmed that the mother is the main source of infection and that contamination occurs at the time of birth.

Age Factors↗
PubMed1976

A comparison of the evolution of transmitted IgG immunoglobulin and diphtheria antitoxin titers in the newborn.

The evolution of the titers of transmitted IgG and diphtheria antitoxin was studied in 20 neonates during the first 2 months of life (6 serum samples for each). A rapid fall of the passive IgG titer was observed during the first weeks: as a rule the higher the initial titer the greater the fall. After the 15th day the rate of decline slows down. The evolution of the titer of transmitted maternal diphtheria antitoxin depends also on the initial level, and if it is low it can remain more or less constant for a long time. The initial level of passive IgG does not influence the drop in diphtheria antitoxin titre and vice versa. Therefore, the evolution of total IgG and diphtheria antitoxin levels appear not to be interdependent.

Age Factors↗
PubMed1976

[Indirect hemagglutination test for detection of antibodies to cytomegalovirus in blood collected on blotting paper (author's transl)].

Indirect hemagglutination test for detection of antibodies to cytomegalovirus is highly sensitive and reproducible, if employed in well-defined conditions. Standardization of the various factors involved is necessary as well as their reciprocal equilibrium : sheep erythrocytes, antigen, dilution of tanin, buffers quality. The hemagglutination test can be performed on small volumes such as blood collection on blotting paper (PKU). Antibody titers were compared in the serum and the blood so collected in 104 subjects : the results were very similar and no "false negative" were found in any case. This way of collecting blood and hemagglutination are technical improvements in epidemiologic studies of cytomegalovirus infection. It can be hoped they will be adapted to other group herpes infections.

Animals↗