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H Grasselier

Publications and source records attributed to H Grasselier.

5 recordsLinked to original sources
PubMed1998

Antimicrobial susceptibility of Haemophilus influenzae in the respiratory tracts of patients with cystic fibrosis.

We analyzed the antimicrobial susceptibilities of Haemophilus influenzae isolates from 157 sputum specimens prospectively collected from 39 cystic fibrosis (CF) patients during a 2-year study. These isolates were characterized by random amplified polymorphic DNA analysis and major outer membrane protein (MOMP) analysis to identify H. influenzae strains and MOMP variants and to assess their persistence in the respiratory tract. Among the 247 H. influenzae isolates, 16 (6.5%) produced beta-lactamase. The 231 beta-lactamase-negative isolates represented 85 H. influenzae strains, 61 MOMP variants derived from 27 of these strains, and 85 persistent isolates identical to strains or MOMP variants. All beta-lactamase-negative isolates were tested for susceptibility to ampicillin, amoxicillin-clavulanic acid, cefuroxime, cefotaxime, cefaclor, imipenem, tetracycline, and trimethoprim-sulfamethoxazole by disk diffusion testing. Eleven (13%) H. influenzae strains, 18 (30%) MOMP variants, and 30 (35%) persistent isolates were resistant to one or more of the antibiotics tested. Antimicrobial susceptibility was decreased among MOMP variants and persistent isolates compared to nonpersistent H. influenzae strains, and changes in susceptibility occurred irrespective of MOMP variation. We conclude that the decreased antimicrobial susceptibility of H. influenzae during persistence contributes to the poor eradication of H. influenzae from the respiratory tracts of CF patients.

Adolescent↗
PubMed1996

Variation in metabolic enzyme activity of persistent Haemophilus influenzae in respiratory tracts of patients with cystic fibrosis.

Haemophilus influenzae organisms were isolated from sputum specimens prospectively collected from 40 patients with cystic fibrosis during 2 years to study variations in the metabolic enzyme activities of persistent H. influenzae strains as determined by biotyping. In total, 97 distinct H. influenzae strains without variations in their major outer membrane protein (MOMP) patterns and 73 MOMP variants derived from 30 of these distinct strains were obtained. Twelve distinct strains and 42 MOMP variant strains were isolated at multiple time points during the study period, indicating the persistence of these strains. Among the 54 persistent H. influenzae strains, 22 (41%) strains with stable MOMP compositions showed random variations in biotypes. In 39 of 103 (38%) H. influenzae strains, biotype changes coincided with MOMP variations. Biotype variations were the result of both the loss and the acquisition of enzyme activities. The results of the study indicate that changes in metabolic enzyme activity occur randomly during the persistence of H. influenzae organisms in cystic fibrosis patients, irrespective of MOMP variations.

Cystic Fibrosis↗
PubMed1995

Multiple Haemophilus influenzae strains and strain variants coexist in the respiratory tract of patients with cystic fibrosis.

To investigate the epidemiology of nontypeable Haemophilus influenzae in the respiratory tract of cystic fibrosis (CF) patients, H. influenzae isolates from sputum specimens of 40 CF patients were analyzed longitudinally for 2 years. The isolates were characterized by analysis of the major outer membrane protein (MOMP) patterns. MOMP variant H. influenzae strains were discriminated from distinct strains by randomly amplified polymorphic DNA analysis of genomic DNA. Multiple H. influenzae strains and MOMP variant strains were isolated from single sputum specimens of 29 patients. In 22 patients, a distinct H. influenzae strain persisted over time (median persistence, 8 months; range 2-24). In general, the appearance of MOMP variant strains did not coincide with the occurrence of exacerbations.

Bacterial Outer Membrane Proteins↗
PubMed1993

N-acetyl-D-glucosamine medium improves recovery of Haemophilus influenzae from sputa of patients with cystic fibrosis.

A modified selective medium supplemented with N-acetyl-D-glucosamine (NAG), hemin, and NAD plus two cefsulodin disks, for primary isolation of nonencapsulated Haemophilus influenzae from sputum of patients with cystic fibrosis, is described. Isolation of H. influenzae from this medium, designated NAG medium, was compared with recovery by standard media and immunochemical detection of H. influenzae with monoclonal antibody 8BD9. The H. influenzae recovery rate increased from 31% with standard media to 42% with NAG medium. H. influenzae was detected by immunoperoxidase staining in 54% of the sputum specimens. The results of this study demonstrate that NAG medium improves H. influenzae recovery, although immunoperoxidase staining is superior for detection of H. influenzae from sputum of cystic fibrosis patients.

Acetylglucosamine↗