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J F Meis

Publications and source records attributed to J F Meis.

At least 127 records · Page 7Linked to original sources
PubMed1994

Plasmodium falciparum liver stage antigen-1 is well conserved and contains potent B and T cell determinants.

We have previously identified a Plasmodium falciparum liver stage-specific Ag (LSA-1) found to encode tandem 17 amino acid repeats harboring B cell determinants. Here we extend this study in terms of sequence analysis, protein localization, and immunologic properties. Analysis of the N- and C-terminal regions of LSA-1 from the T9/96 clone reveals high sequence conservation with LSA-1 from NF54. This 200-kDa protein is detected throughout liver schizogony and accumulates in the parasitophorous vacuole space. In our investigation of T and B cell responses to LSA-1, we have focused on both the area of the C-terminal, nonrepetitive "hinge" region and the conserved repetitive region and derived synthetic peptides. These were found to contain major B and T cell determinants. High prevalences and elevated Ab levels to LSA-1, directed primarily, although not exclusively, to the repetitive region, were detected in sera of individuals from one moderately high and two low transmission malaria-endemic areas (prevalences of 97%, 75, and 77%, respectively). In one of these low transmission areas, secretion of the cytokine IFN-gamma, known to inhibit malaria liver stages, and T cell proliferation were detected in PBMC of 22 to 48% and 6 to 20%, respectively, of individuals in response to separate LSA-1 peptides. These results complement the recent finding of conserved CTL epitopes in LSA-1 and support the assertion that immune responses to LS Ag are involved in protection against malaria pre-erythrocytic stages.

Amino Acid Sequence↗
PubMed1994

Genotypic characterization of sequential Candida albicans isolates from fluconazole-treated neutropenic patients.

A polymerase chain reaction (PCR)-mediated genotyping assay for Candida albicans has been developed. By amplification of genomic regions bordered by eukaryotic or prokaryotic repeat-like motifs, differences between C. albicans isolates can be determined. The resolution of this typing procedure is at least as good as that of other genotypic assays. To ascertain the epidemiologic and clinical usefulness of this PCR genotyping, a retrospective analysis of serial C. albicans isolates from neutropenic adults treated with fluconazole was done. By PCR genotyping, 40 strains were detected in 24 patients. Eighteen C. albicans strains were found on multiple samplings in individual patients. It appears that most patients remain colonized with a C. albicans strain of constant genotypic characteristics. However, exceptions were observed. In 7 (29%) of 24 patients, strains deviating from the most frequently encountered type could be identified. All but 1 strain remained susceptible to fluconazole in vitro after treatment in vivo. It was not possible to demonstrate a relation of genotypic variation and antifungal susceptibility changes.

Adult↗
PubMed1994

Severe osteomyelitis due to the zygomycete Apophysomyces elegans.

We describe a previously healthy 69-year-old man presenting with osteomyelitis of the humerus due to the zygomycete Apophysomyces elegans. The infection was acquired in Aruba, The Netherlands Antilles. The skin provided the most likely portal of entry, although there was no history of a traumatic inoculation. The patient had no history of diabetes, and no underlying immune defects were found. Despite treatment with 7.9 g of amphotericin B, an interthoracoscapular amputation proved necessary to curtail the rapid spread of the fungus in this immunocompetent host.

Aged↗
PubMed1994

General primer-mediated PCR for detection of Aspergillus species.

A PCR assay was developed for the diagnosis of invasive aspergillosis in immunocompromised patients. For this purpose, the complete nucleotide sequences of the genes encoding the 18S rRNA of Aspergillus nidulans, Aspergillus terreus, Aspergillus niger, and Aspergillus flavus were elucidated and aligned to the sequences of Aspergillus fumigatus and other clinically relevant prokaryotic and eukaryotic microorganisms. Genus-specific sequences could be identified in the V7 to V9 region of 18S rRNA. By using hot-start PCR, Southern blot hybridization, and restriction enzyme analysis, Aspergillus-specific and -sensitive determination was achieved. Five of six immunosuppressed mice experimentally infected with A. fumigatus developed infection, and rRNA could be detected in each case, even in livers with the absence of positive cultures. Aspergillus species were detected by PCR in four neutropenic patients with proven aspergillosis, although Aspergillus species had been isolated from only one bronchoalveolar lavage (BAL) fluid sample. Aspergillus species were detected by PCR in two more patients suspected of having infection. Positive PCR signals were obtained from the BAL samples of 3 of 8 neutropenic patients who had developed pulmonary infiltrates, but none were obtained from the samples of 14 nonimmunosuppressed patients. These results indicate the potential value of PCR to detect Aspergillus species in BAL samples and, therefore, to identify neutropenic patients at risk for invasive aspergillosis.

Adult↗
PubMed1994

Cellulitis as first clinical presentation of disseminated cryptococcosis in renal transplant recipients.

Two renal transplant recipients with cellulitis due to Cryptococcus neoformans are described. The patients were treated empirically for a presumed bacterial erysipelas, but without response. Examination of skin biopsies revealed C. neoformans as the causative organism. In both patients the cellulitis was the presenting clinical manifestation of disseminated cryptococcosis. Therapy with antifungal agents was successful. Disseminated cryptococcal disease occurs mainly in immunocompromised patients. When left untreated, it nearly always has a fatal course. Early diagnosis and appropriate therapy are therefore essential.

Adult↗
PubMed1994

[Fingerprinting with the polymerase chain reaction: confirmation of a Enterobacter cloacae epidemic in a neonatal intensive care unit].

Between end December 1993 and end January 1994 a cluster of children infected/colonized with Enterobacter cloacae was seen in the neonatal intensive care unit of the University Hospital Nijmegen. The results of the epidemiological investigation are reported, which was aimed to differentiate between a random cluster of endogenously acquired Enterobacter strains and those possibly acquired exogenously via cross-infection. 5 isolates of the 7 patients were available for fingerprinting using interrepeat PCR. According to the fingerprint pattern, 4 of these isolates were identical, thereby suggesting cross-infection among the children. 3 neonates were colonized/infected with genotypically different isolates, suggesting that the infection/colonization developed endogenously. A control strain isolated from a patient at another ward showed the same genotype as the outbreak isolates. The transmission took probably place through one of the surgeons who, among all possible health care workers, were the only professional group treating patients in both units.

Cross Infection↗
PubMed1993

[Postanginal sepsis caused by Fusobacterium necrophorum: Lemierre syndrome].

Postanginal sepsis or Lemierre's syndrome is characterised by septic thrombophlebitis of the jugular vein, metastatic abscesses in the lungs, soft tissues, joints or elsewhere, occurring several days to two weeks after tonsillitis or pharyngitis. The primary pathogen is a Gram-negative anaerobic rod, mostly Fusobacterium necrophorum. Previously healthy, young adults are affected mainly and the syndrome was seen more frequently in the pre-antibiotic era than it is nowadays. In the three young patients described here, a girl aged 15 and two boys aged 18 and 16, F. necrophorum was isolated from blood or pus. Histories and examinations were suggestive of Lemierre's syndrome. Ultrasound and CT scanning of the neck and other localisations proved to be important diagnostic tools in assessing the diagnosis. Response to therapy was slow and depended in at least one case on adequate drainage of abscesses. If the syndrome is suspected, initial antibiotic treatment should provide adequate coverage of anaerobic bacteria. In previously healthy patients with chills and fever occurring several days after a sore throat, Lemierre's syndrome should be considered.

Adolescent↗
PubMed1993

Rapid diagnosis of acute meningococcal infections by needle aspiration or biopsy of skin lesions.

OBJECTIVES: To evaluate the usefulness of Gram staining and culture of skin lesions in patients with acute meningococcal infections. DESIGN: Retrospective study. SETTING: Community hospital and intensive care unit of a teaching hospital. SUBJECTS: 51 patients admitted from 1989 to 1993 with proved meningococcal infections and microbiological examination of specimens from skin lesions. INTERVENTIONS: Needle aspiration of a skin lesion before start of antibiotic treatment in 26 patients in the community hospital; punch biopsy of skin lesion after start of antibiotic treatment in 25 patients in the teaching hospital. MAIN OUTCOME MEASURES: Detection of meningococci by Gram staining of specimens from skin lesions according to category of infection (meningococcaemia, meningitis, meningitis with shock, or septic shock without meningitis). RESULTS: Bacteria were detected in the specimen from haemorrhagic skin lesions by culture or Gram staining, or both in 32 (63%) patients. The sensitivity of the Gram stain was 51% and did not differ significantly from its sensitivity in detecting bacteria in cerebrospinal fluid. In meningococcal sepsis, however, a Gram stained skin lesion was significantly more sensitive (72%) than Gram stained cerebrospinal fluid (22%). In patients with meningitis skin lesions gave positive results on staining more often if shock was present. The results for punch biopsy specimens were not affected by antibiotics as Gram staining gave positive results up to 45 hours after the start of treatment and culture gave positive results up to 13 hours. CONCLUSION: Microbiological examination of skin lesions is informative, especially in patients with sepsis and inconclusive results from cerebrospinal fluid, and may provide a diagnosis in such patients within 45 minutes. It differentiates well between meningitis with and without haemodynamic complications, and the result is not affected by previous antibiotic treatment.

Acute Disease↗
PubMed1993

Chronic polyarthritis due to Pseudomonas aeruginosa.

We present a 45-year-old male patient with chronic obstructive lung disease treated with low-dose corticosteroids, who developed a chronic septic polyarthritis due to Pseudomonas aeruginosa following a surgical wound infection. Due to the mild synovitis and the absence of systemic signs of infection the diagnosis was delayed for nearly 2 years and resulted in severe joint destruction.

Arthritis↗
PubMed1993

Rapid, polymerase chain reaction-based identification assays for Candida species.

Polymerase chain reaction (PCR) amplification of specific regions in the genomes of a variety of lower eukaryotes permits rapid identification of these microorganisms. First, on the basis of the presence of both constant and variable regions in the small subunit (ssu) rRNA, a nested PCR for direct identification of various Candida species can be designed. Amplification of the entire ssu rRNA gene and subsequent reamplification of variable sequences within the V4 domains of these PCR products were combined with direct sequencing. Restriction enzyme maps were made, and species-specific oligonucleotides for hybridization analysis were selected. Unequivocal discrimination of four of the major human pathogenic yeasts (Candida albicans, Candida glabrata, Candida tropicalis, and Candida krusei) is possible if a combination of these techniques is used. Second, by using oligonucleotides aimed at repeated sequences which occur at dispersed positions in the genomes of all eukaryotes, species-specific DNA fingerprints could be generated. This interrepeat PCR using genomic DNA as template proved to be an effective tool in Candida species typing. Both techniques described here can be extrapolated to the high-speed diagnostics of numerous other prokaryotic and eukaryotic pathogens.

Base Sequence↗