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J F Meis

Publications and source records attributed to J F Meis.

At least 91 records · Page 5Linked to original sources

A primer on cytokines: sources, receptors, effects, and inducers.

Protection against pathogens is a prerequisite for survival of most organisms. To cope with this continuous challenge, complex defense mechanisms have evolved. The construction, adaptation, and maintenance of these mechanisms are under control of an extensive network of regulatory proteins called cytokines. A great number of cytokines have been described over the last 2 decades. This review consists of an overview of cytokines that are involved in immune responses and describes some historical and general aspects as well as prospective clinical applications. Major biological effects together with information on cytokine receptors, producers, inducers, and biochemical and molecular characteristics are listed in tables. In addition, some basic information is given on cytokine receptor signal transduction. Finally, the recent discoveries of cytokine receptors functioning as coreceptors in the pathogenesis of human immunodeficiency virus are summarized.

Chemokines↗

Specificity of a sandwich enzyme-linked immunosorbent assay for detecting Aspergillus galactomannan.

The specificity of a sandwich enzyme-linked immunosorbent assay (ELISA) for detecting Aspergillus galactomannan was tested with exoantigens of 29 fungi cultured from clinical specimens. Cross-reactivity was observed with Penicillium chrysogenum, Penicillium digitatum, and Paecilomyces variotii. Furthermore, 40 serum samples obtained from bacteremic patients with hematologic malignancies were retrospectively tested by sandwich ELISA. False-positive reactions with the serum were reproducible but did not correspond with the results of culture of specific microorganisms. Moreover, the microorganisms cultured from the blood showed no reactivity by the sandwich ELISA.

Aspergillus↗

Fatal pulmonary infection caused by the basidiomycete Hormographiella aspergillata.

A fatal case of a pulmonary infection caused by Hormographiella aspergillata, the anamorph of the mushroom Coprinus cinereus, is reported for a patient receiving treatment for a second relapse of acute lymphoblastic leukemia. The filamentous basidiomycete was identified with restriction fragment length polymorphism patterns of PCR-amplified internally transcribed spacers and small subunit ribosomal DNA with four restriction enzymes. The patient failed to respond to treatment with amphotericin B and itraconazole. The fungus was cultured from the lungs at autopsy: the MIC of amphotericin B for the fungus was low (0.5 mg/liter), and that of itraconazole was high (8 mg/liter).

Adult↗

Severe keratitis due to Nocardia farcinica.

Keratitis due to Nocardia farcinica occurred in a 49-year-old female after inappropriate cleaning of her semipermeable rigid contact lenses with basin-stored water during a holiday in France. N. farcinica was differentiated from Nocardia asteroides by its growth at 45 degrees C, acid production from rhamnose, its opacification of Middlebrook 7H10 agar, and its marked degree of resistance to all cephalosporins, aminoglycosides, tetracyclins, macrolides, and trimethoprim-sulfamethoxazole. To the best of our knowledge, this is the first reported case of human N. farcinica keratitis, confirming that this microorganism can be responsible for serious human disease.

Contact Lenses↗

Outbreak of amoxicillin-resistant Haemophilus influenzae type b: variable number of tandem repeats as novel molecular markers.

An outbreak caused by amoxicillin-resistant Haemophilus influenzae type b was noted among patients suffering from chronic obstructive pulmonary disease. Since infections were clustered in time and place, an ongoing outbreak was suspected. The spread of the strain and the course of the outbreak could be followed by random amplification of polymorphic DNA (RAPD) analysis of the different bacterial isolates. In addition, studies were aimed at the determination of length polymorphism in regions of repetitive DNA. By PCR-mediated amplification of variable number of tandem repeat regions (VNTRs), additional insight into the genome composition of the epidemic strain was gained. Our results show that VNTRs comprising repeat units that are 3, 5, or 6 nucleotides in length provided stable genetic markers that can be used for molecular typing of H. influenzae type b. VNTRs built from tetranucleotide units, however, appear to be hypervariable and not suited for epidemiological studies. The observed variability in this latter class of VNTRs might be reminiscent of the bacterium's capacity to deal with unfavorable host factors.

Amoxicillin↗

Wooden sticks as the source of a pseudoepidemic of infection with Rhizopus microsporus var. rhizopodiformis among immunocompromised patients.

Wooden sticks used to suspend feces obtained for surveillance cultures were found to be the source of Rhizopus microsporus var. rhizopodiformis causing a pseudo-outbreak among 17 immunocompromised patients cared for in three different wards. Nonsterile wooden products should therefore not be used for collecting, handling, and processing specimens for microbiological examination.

Cross Infection↗

[Tinea capitis].

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Animals↗

[Problems of resistance in Streptococcus pneumoniae].

Penicillin-resistant pneumococci are an increasing worldwide problem that until now has spared the Netherlands and a small number of other European countries. In countries with resistant pneumococci empirical therapy of otitis media and of meningitis is difficult. Special antibiotics such as clindamycin and ceftriaxone may be needed or combinations of vancomycin and high doses of cephalosporin. In spite of antibiotic resistance pneumococcal pneumonia can be treated successfully with high doses of benzylpenicillin or cephalosporin. In case of an infection outside the central nervous system, it is not clear what level of minimal inhibitory concentration indicates that therapy will fail, probably > 4 mg/l. Even in regions with much resistance such levels are rare. It is fortunate that antibiotic resistance only occurs in a limited number of pneumococcal strains, which in addition happen to be included in antipneumococcal vaccines.

Humans↗

Occurrence of yeast bloodstream infections between 1987 and 1995 in five Dutch university hospitals.

The aim of this study was to identify retrospectively trends in fungal bloodstream infections in The Netherlands in the period from 1987 to 1995. Results of over 395,000 blood cultures from five Dutch university hospitals were evaluated. Overall, there were more than 12 million patient days of care during the nine-year study period. The rate of candidemia doubled in the study period, reaching an incidence of 0.71 episodes per 10,000 patient days in 1995. The general increase in candidemia was paralleled by an increase in non-Candida albicans bloodstream infections, mainly due to Candida glabrata. However, more than 60% of the infections were caused by Candida albicans. Fluconazole-resistant species such as Candida krusei did not emerge during the study period. The increasing rate of candidemia found in Dutch university hospitals is similar to the trend observed in the USA, but the rate is lower and the increase is less pronounced.

Antifungal Agents↗

Genotypic characterization of sequential Aspergillus fumigatus isolates from patients with cystic fibrosis.

Twenty-three sequential Aspergillus fumigatus sputum isolates, which had been collected over a period of 2 years, from two patients with cystic fibrosis were genotyped by random amplified polymorphic DNA PCR and restriction fragment length polymorphism analysis. In patient B, one genotype was predominantly present in the sputum samples, while in the other patient up to nine different genotypes were identified. This study suggests that different patterns of colonization with A.fumigatus exist in patients with cystic fibrosis.

Aspergillus fumigatus↗

Immunoperoxidase staining for identification of Aspergillus species in routinely processed tissue sections.

AIMS: To evaluate the performance of an immunoperoxidase stain using the monoclonal antibody EB-A1 to detect Aspergillus species in formalin fixed, paraffin wax embedded tissue. METHODS: The monoclonal antibody EB-A1 directed against galactomannan was used to detect Aspergillus species in 23 patients with suspected or confirmed invasive aspergillosis. Immunostaining was performed on formalin fixed, paraffin wax embedded tissue using the streptavidin-biotin method and compared with conventional haematoxylin and eosin, periodic acid-Schiff, and Gomori-Grocott stains. Results of immunostaining were semiquantitatively analysed with regard to both intensity of staining and number of positively staining micro-organisms. Tissue sections from 16 patients with confirmed invasive mycoses due to Candida species, Apophysomyces elegans, Rhizopus oryzae, Pseudallescheria boydii and Histoplasma capsulatum were used as controls. RESULTS: In 19 (83%) of 23 cases invasive aspergillosis was confirmed by both histological examination and culture (18 Aspergillus fumigatus and one A flavus). Immunoperoxidase stains were positive in 17 (89%) of 19 cases including one case of disseminated infection due to A flavus. Furthermore, the immunoperoxidase stain was positive in a culture negative tissue section with histological evidence of mycelial development, indicating the presence of Aspergillus species. Some cross-reactivity was observed with the highly related fungus P boydii, although the number of mycelial elements that stained was low. CONCLUSIONS: Immunoperoxidase staining using the monoclonal antibody EB-A1 performs well on routinely processed tissue sections and permits detection and generic identification of Aspergillus species, although it was no better than conventional histopathology in identifying the presence of an infection. An additional advantage is that the immunostain may help to provide an aetiological diagnosis when cultures remain negative.

Adolescent↗

Use of interrepeat PCR fingerprinting to investigate an Acinetobacter baumannii outbreak in an intensive care unit.

An epidemiological investigation of an outbreak of Acinetobacter baumannii among patients on 2 closely related intensive care units (ICU) was performed by molecular typing with interrepeat polymerase chain reaction (interrepeat PCR). 31 A. baumannii isolates obtained from 15 ICU patients were characterized. All patients were infected or colonized with A. baumannii. After identification of the outbreak, 6 environmental isolates were collected from tap-water, sinks and cleaning detergents. PCR fingerprinting identified 3 genotypes among the outbreak-related strains. One predominant genotype was demonstrated in 14/15 patients and this genotype was also found among all environmental isolates. The cluster of A. baumannii represented an outbreak of 1 genotype, suggesting cross-contamination. The finding of the identical genotype among all environmental strains indicated a common environmental source causing the outbreak. The outbreak was controlled after reimplementation of an effective disinfection of workplace surfaces. This survey proved interrepeat PCR to be a rapid and reliable method to differentiate A. baumannii strains, thereby allowing epidemiological surveillance of large amounts of strains and early interventions to control outbreaks.

Acinetobacter↗