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E Grimprel

Publications and source records attributed to E Grimprel.

32 records · Page 2Linked to original sources
PubMed1996

Comparative DNA analysis of Bordetella pertussis clinical isolates by pulsed-field gel electrophoresis, randomly amplified polymorphism DNA, and ERIC polymerase chain reaction.

We used DNA fingerprinting by pulsed-field gel electrophoresis (PFGE), randomly amplified polymorphic DNA (RAPD) and PCR amplification of enterobacterial repetitive intergenic consensus sequences (ERIC-PCR) to compare 15 clinical isolates of Bordetella pertussis recovered between August 1993 and September 1995 from 13 infants and two adults, living in the same geographic area. PFGE produced 10 patterns and made it possible to differentiate all the isolates and to indicate an intrafamilial transmission. RAPD and ERIC-PCR generated banding patterns with small differences and had a poor discriminatory power. During the last 2 years, at Armand-Troussau pediatric hospital, 10 distinct clones of clinical B. pertussis isolates, with a predominant clone including seven strains, could be determined by the PFGE method.

Adult↗
PubMed1996

Future combined vaccines.

The increasing number of useful vaccines for infants and children justifies the development of new combined vaccines. New methodologies are needed for evaluation of efficacy, especially for acellular pertussis vaccines. Such evaluation requires the use of previous immunogenicity studies as a means to seek immune interference that might lead to decreased efficacy. Finally, definitive efficacy could be assessed by long-term postmarketing epidemiologic surveillance. Different combinations are discussed in relation to age of recipients (infants, children, adolescents, and adults) and national or regional epidemiologies.

Adult↗
PubMed1996

Long-term human serum antibody responses after immunization with whole-cell pertussis vaccine in France.

Three hundred sixty children were tested for pertussis serology 0.5 to 1.58 months after complete whole-cell pertussis vaccination. An immunoblot assay was used to detect serum antibodies to pertussis toxin, filamentous hemagglutinin, adenylate cyclase-hemolysin, and pertactin, and agglutination was used for detection of anti-agglutinogen antibodies. Antibodies against pertussis toxin, pertactin, and agglutinogens decreased rapidly after vaccination but increased secondarily, suggesting exposure to infected persons. In contrast, anti-filamentous hemagglutinin antibodies persisted and anti-adenylate cyclase-hemolysin antibodies increased continuously, suggesting either cross-reaction with non-Bordetella antigens or exposure to Bordetella isolates expressing these two antigens, including Bordetella pertussis. These data suggest that unrecognized pertussis is common in France despite massive and sustained immunization in infants and that vaccinated children become susceptible to infection more than 6 years after their last vaccination.

Adenylate Cyclase Toxin↗
PubMed1993

Western blot analysis of antibody responses of young infants to pertussis infection.

Western blot and agglutination techniques were used to analyze the antibody responses to Bordetella pertussis in 27 infants less than six month of age with presumed pertussis infection. The antibody response to the Bordetella pertussis adhesions filamentous hemagglutinin, pertactin and agglutinogens, and to the Bordetella pertussis toxins pertussis toxin and adenylate cyclase-hemolysin were compared. Infection induced intense antibody responses to filamentous hemagglutinin, pertussis toxin and adenylate cyclase-hemolysin. Antibodies to agglutinogens were never detected, and antibodies to pertactin were rarely detected in infected infants' sera. Therefore, determination of anti-agglutinogens levels only is not suitable for the serological diagnosis of pertussis in young infants. Use of purified filamentous hemagglutinin, pertussis toxin and adenylate cyclase-hemolysin in Western blot analysis may improve the serodiagnosis of Bordetella infections. However, care must be exercised in distinguishing between the antibody response in young infants and maternally derived antibodies.

Adenylate Cyclase Toxin↗
PubMed1993

Virus isolation, polymerase chain reaction and in vitro antibody production for the diagnosis of pediatric human immunodeficiency virus infection.

Viral culture (VC), polymerase chain reaction (PCR) and in vitro antibody production (IVAP) by peripheral blood mononuclear cells were compared for the early diagnosis of HIV-1 infection in 46 infants born to HIV-1 seropositive mothers. The ten children considered infected on the basis of clinical signs and persistence of anti-HIV-1 antibodies had at least one positive viral culture and seven were always positive in both PCR and IVAP tests. PCR and IVAP tests were occasionally negative in three infected children. Among 30 healthy children who became seronegative and were always negative for viral culture, 22 (73.3%) were also repeatedly negative in PCR and IVAP. We report 6 cases of children classified as P2A at the term of this study but who had lost anti-HIV-1 antibodies. They presented at least one positive viral culture and occasional positive PCR and/or IVAP results. The results indicate that the combination of viral culture, PCR and IVAP tests improves the early diagnosis of pediatric HIV infection.

Antibody Formation↗
PubMed1993

Evaluation of molecular methodologies and rabbit infectivity testing for the diagnosis of congenital syphilis and neonatal central nervous system invasion by Treponema pallidum.

IgM immunoblotting and polymerase chain reaction (PCR) were evaluated for use in diagnosing congenital syphilis, and the prevalence of central nervous system (CNS) invasion by Treponema pallidum during congenital infection was examined. The results of rabbit infectivity testing (RIT) on serum and cerebrospinal fluid (CSF) of 19 infants born to mothers with untreated early syphilis were compared with results of PCR and IgM immunoblotting. Seven infants had clinical evidence of congenital syphilis supported by positive serum IgM immunoblot (7/7), PCR (6/7), and RIT (3/3). Six symptomatic infants (86%) had T. pallidum isolated from CSF by RIT; 5 of 6 RIT-positive CSF samples were positive by PCR, and 2 also were reactive by IgM immunoblot. In 12 asymptomatic infants, 5 (42%) had a reactive serum IgM immunoblot and in 4 of these IgM reactivity was the only evidence of congenital infection. CNS invasion by T. pallidum was uncommon among asymptomatic infants; only 1 (8%) was positive by CSF RIT. The excellent agreement between RIT and PCR further substantiates the use of PCR as a surrogate for RIT. Our data indicate that the diagnosis of asymptomatically infected neonates will require a comprehensive approach using assays for both specific neonatal IgM and T. pallidum DNA in serum and CSF.

Adolescent↗
PubMed1993

Comparison of polymerase chain reaction, culture, and western immunoblot serology for diagnosis of Bordetella pertussis infection.

Polymerase chain reaction (PCR) amplification of the pertussis toxin promoter region was used to detect Bordetella pertussis infection in nasopharyngeal aspirates collected from 24 infants and children infected with pertussis and 13 adult contacts during an epidemiological study. The sensitivity of this PCR assay was approximately one bacterium, and the assay was specific for B. pertussis in tests with other Bordetella species and other respiratory pathogens. The pertussis case definition required a cough with a duration of more than 21 days for infants and children and laboratory confirmation by serology as the primary detection method for infants, children, and adults. The sensitivity of PCR and culture on Bordet-Gengou agar medium was assessed with regard to the case definitions. In the group of infants and children (index cases), the sensitivities of the culture and the PCR were 54.1% (13 of 24) and 95.8% (23 of 24), respectively. In the adult group (household contacts), the sensitivities of the two methods were 15.4% (2 of 13) and 61.5% (8 of 13), respectively. PCR combined with pertussis-specific serology appears to be a useful tool for diagnosis of pertussis especially in epidemiological studies.

Adult↗
PubMed1993

[Role of dexamethasone in the treatment of purulent meningitis in infants and in children].

Accumulating evidence tends to demonstrate that inflammatory processes are responsible for neurological damage and sequelae in bacterial meningitis in children and infants. Massive liberation of bacterial cell wall components (Lipopolysaccharide, acid teichoic polymers) induce a cascade of reactions including the secretion of many cytokines (such as TNF alpha and IL-1 beta) and prostaglandins (such as PAF and PGE2) which in turn leads to the development of cerebral oedema, intracranial hypertension and cerebral blood flow reduction. Dexamethasone (DXM) is effective at the beginning of the inflammatory cascade and its utilisation in the meningitis experimental model in animals has shown significant reduction in the inflammatory response to bacterial meningitis. The first clinical studies using DXM as an adjunctive therapy to antibiotics have demonstrated its beneficial effect in terms of complications and long-term neurological sequelae in Haemophilus influenzae meningitis in children and infants. It seems that a similar effect can be obtained in meningococcal and pneumococcal meningitis. Little information is actually available concerning the use of DXM in penicillin-resistant pneumococcal meningitis. The rare reported cases of ceftriaxone failure with DXM as treatment of penicillin-resistant pneumococcal meningitis had a favorable outcome with the use of vancomycin.

Animals↗
PubMed1991

Characteristics of experimental Candida albicans infection of the central nervous system in rabbits.

Different concentrations (10(7), 10(5), 10(3) cfu/ml) of Candida albicans were injected intracisternally in rabbits. The highest inoculum was fatal within 14 h in all animals. In recipients of 10(5) and 10(3) cfu/ml inocula, the mean +/- SD peak cerebrospinal fluid (CSF) tumor necrosis factor-alpha (TNF alpha) concentrations were 1.6 +/- 2.42 and 0.3 +/- 0.59 ng/ml, respectively, at 6 h; the mean +/- SD CSF leukocyte and protein concentrations were 6291 +/- 6515 and 453 +/- 674 cells/mm3 (at 24 h) and 118 +/- 90 and 109 +/- 122 mg/dl (at 12 and 24 h), respectively. At 6-10 days after inoculation, a second peak of TNF alpha activity was accompanied by increased CSF inflammation. Mortality in the 10(5) and 10(3) cfu/ml inoculum groups was 56% and 22%, respectively. Fatal infection was associated with higher second CSF peak TNF alpha and leukocyte concentrations and a larger proportion of culture-positive CSF samples. Histopathology revealed hyphal invasion, vasculitis, abscesses, and acute and chronic inflammatory infiltration of meninges and brain parenchyma. This model can be useful for evaluation of the pathogenesis and therapy of central nervous system fungal infections.

Animals↗
PubMed1991

Sensitive detection of Treponema pallidum by using the polymerase chain reaction.

We have developed a sensitive assay for Treponema pallidum subsp. pallidum (T. pallidum), the agent of veneral syphilis, based upon the polymerase chain reaction (PCR). A 658-bp portion of the gene encoding the 47-kDa membrane immunogen was amplified, and the PCR products were probed by DNA-DNA hybridization with a 496-bp fragment internal to the amplitifed DNA. The assay detected approximately 0.01 pg of purified T. pallidum DNA, and positive results were obtained routinely from suspensions of treponemes calculated to contain 10 or more organism and from some suspensions calculated to contain a single organism. Specific PCR products were obtained for the closely related agent of yaws, Treponema pallidum subsp. pertenue, but not with human DNA or DNAs from other spirochetes (including Borrelia burgdoferi), skin microorganisms, sexually transmitted disease pathogens, and central nervous system pathogens. T. pallidum DNA was detected in serum, cerebrospinal fluids, and amniotic fluids from syphilis patients but not in in nonsyphilitic controls. T. pallidum DNA was also amplified from paraffin-embedded tissue. The diagnosis of syphillis by using PCR may become a significant addition to the diagnostic armamentarium and a valuable technique for the investigation of syphilis pathogenesis.

Animals↗
PubMed1991

Use of polymerase chain reaction and rabbit infectivity testing to detect Treponema pallidum in amniotic fluid, fetal and neonatal sera, and cerebrospinal fluid.

The diagnosis of congenital syphilis continues to pose a difficult clinical challenge. Because the serodiagnosis of congenital syphilis has significant limitations, the direct detection of Treponema pallidum in suspect neonatal tissues or body fluids represents a desirable alternate diagnostic strategy. We developed and applied the polymerase chain reaction (PCR) for the detection of T. pallidum in clinical material relevant to the diagnosis of congenital syphilis but which typically contain factors inhibitory for the PCR. Four methods of specimen processing were examined to circumvent PCR inhibition; clinical materials included amniotic fluids, neonatal sera, and neonatal cerebrospinal fluids. The PCR was 100% specific for T. T. pallidum compared with the sensitive rabbit infectivity test (RIT) for all clinical materials tested. For amniotic fluids, the PCR was 100% sensitive when correlated with the RIT but had a lesser sensitivity when applied to sera or cerebrospinal fluids, which typically contain few treponemes. The combined sensitivity of the PCR for all clinical samples was 78%. Positive PCR results also were obtained among some clinical specimens for which RIT was not performed; these results correlated well with either stigmata or risk factors for congenital syphilis. The combined results suggest that the PCR can be a useful adjunct to the diagnosis and clinical management of congenital syphilis and that it will provide a valuable tool for investigations of the pathogenesis of the disorder.

Amniotic Fluid↗
PubMedDate not supplied

[Epidemiology of pertussis in industrialized countries].

Pertussis remains present in the industrialized world, although the widespread use of whole-cell pertussis vaccine has led to a dramatic decline of the disease. Great differences in immunization policies and coverage explain the uneven epidemiological pattern across the developed world. Different situations can be described. In some countries such as Japan, UK and Italy, concerns about the occurrence of severe adverse events following pertussis vaccination in the 70's led to a reduced acceptance and thus, to a significant decrease in immunization coverage. In Sweden, the protective efficacy of pertussis vaccine was questioned and vaccination was discontinued in 1979. In all these countries, severe epidemics of pertussis were observed in the following years, and immunization was then reinforced in some (UK). In Japan, considerable efforts were made to develop new and safer pertussis acellular vaccines which have replaced the whole-cell vaccine since 1981. In other countries such as the USA and France, despite a continuous immunization programme maintaining a sustained and high coverage, a resurgence of the disease was observed in association with a modification of the age-distribution. Vaccinated adults became susceptible to the infection because of progressive waning, vaccine-induced immunity. These patients contaminated very young and thus, unvaccinated infants. These observations underline the need for early immunization in infants as well as the importance of late booster doses to be given to older children or adults.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗