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H Colding

Publications and source records attributed to H Colding.

At least 19 recordsLinked to original sources
PubMed2000

Potentiation of the action of metronidazole on Helicobacter pylori by omeprazole and bismuth subcitrate.

Treatment failures using triple therapy that include metronidazole, are common in patients infected with metronidazole-resistant Helicobacter pylori in the gastric mucosa. Higher eradication rates in such patients have been described when treatment regimens include bismuth salts compared to regimens that include proton pump inhibitors. In the present study, the synergistic effect of subinhibitory concentrations (0.25-0.5 MIC) of either bismuth subcitrate or omeprazole with metronidazole on the susceptibility of 42 H. pylori strains was investigated by agar dilution method and the Epsilometer test (Etest). With 0.5 MIC of either of the two drugs, the susceptibility of all H. pylori4 mg/l) reverted to being metronidazole sensitive. These results suggested that either bismuth salts or proton pump inhibitors may be effective in the treatment of some infections with metronidazole-resistant H. pylori strains when used in sufficiently high doses.

Antacids↗
PubMed2000

Phenotypic and genotypic characterization of Helicobacter pylori from patients with and without peptic ulcer disease.

BACKGROUND: Helicobacter pylori plays an important role in peptic ulcer disease, although not all H. pylori-infected persons will develop a peptic ulcer. Currently, H. pylori strains cannot be divided into commensals and pathogens. METHODS: Fifty H. pylori strains were cultured from patients divided into five groups on the basis of upper endoscopic findings: gastric ulcer, duodenal ulcer, gastritis, esophagitis, or normal. The ultrastructural adherence pattern in vivo, autoagglutination, hemagglutination, adhesion to human gastric adenocarcinoma (AGS) cells, and the lipopolysaccharide (LPS) profile of H. pylori strains were recorded; randomly amplified polymorphic DNA (RAPD) and urease gene typing were performed and correlated with diagnostic groups. RESULTS: Electron micrographs showed that H. pylori strains from patients with gastric ulcers adhered more frequently through filamentous strands and were less frequently found free in mucus than any other diagnostic group (P < 0.0001). Neither median hemagglutination titer nor median adhesion capacity to a human gastric adenocarcinoma cell line was related to endoscopic findings. Nevertheless, H. pylori strains from patients with gastric ulcers were more prone to autoagglutinate than were strains from the other diagnostic groups (P = 0.03). H. pylori strains from gastric ulcer patients were found to be more homogeneous, as determined by RAPD and urease gene typing, than strains from the other diagnostic groups (P < 0.01). In addition, a positive correlation was found between a patient's age and the adhesion to AGS cells of the patient's H. pylori strain (P = 0.006). CONCLUSION: A combination of an H. pylori autoagglutination test, RAPD, and urease gene typing may be useful in separating gastric ulcer-related strains from duodenal ulcer-related and non-ulcer dyspepsia-related strains.

Adult↗
PubMed1999

[Medical research and gender. An analysis of the preclinical departments at the University of Copenhagen].

The proportion of women among Danish medical graduates increased from 25% to 50% in the years 1970 to 1996. The proportion of women among the medical scientific staff has, however, not changed significantly over this period. At The University of Copenhagen women comprised 16% of the preclinical faculty in 1970 and 21% in 1996, and today's lack of women cannot be explained as a legacy from previous periods. The construction of a professional hierarchy is central in any discussion of position and influence in scientific research. Women at the medical faculties have in many respects a peripheral position. Relatively few have a postgraduate medical degree, they are in general not employed in traditional medical research areas such as physiology and anatomy, and there are disproportionately fewer among the professors. The authors argue that the women's position as non-doctors in low-status areas results in a lack of influence and access to resources.

Career Mobility↗
PubMed1999

[Professional prestige and gender--clinical scientific staff in Copenhagen as an example].

At the clinical medical departments of The University of Copenhagen only 5% of the clinical professors and 18% of the associate professors were women in 1995. Among the other categories of the scientific staff, e.g. assistant professors, 34% were women. There was also an uneven distribution of women among the specialties, ranging from 0% women on the scientific staff of the ear, nose and throat specialty to 75% in geriatrics. Based on a ranking scale for the medical specialties constructed by Album (9), the study shows that the percentage of women within a specialty is negatively correlated to the prestige of the specialty. On Album's scale ranging from 1 (highest) to 22 (lowest) the specialties of the female professors had a mean ranking of 18.5 compared to 12.6 for the male professors. The mean ranking for the associate professors was 15.0 for the women compared to 8.8 for the men.

Career Mobility↗
PubMed1999

Molecular methods for typing of Helicobacter pylori and their applications.

Microbial typing is a useful tool in clinical epidemiology for defining the source and route of infection, for studying the persistence and reinfection rates, clonal selection in the host and bacterial evolution. Phenotypic methods such as biotyping, serotyping and hemagglutinin typing have little discriminatory power compared to genotypic methods concerning the typing of Helicobacter pylori. Therefore great efforts have been made to establish useful molecular typing methods. In this context, the most frequently used genotypic methods are described based on our own experience and the literature: (1) restriction endonuclease analysis, (2) endonuclease analysis using pulsed-field gel electrophoresis, (3) ribotyping, (4) polymerase chain reaction (using either random primers or repetitive DNA sequence primers), and (5) polymerase chain reaction-restriction fragment length polymorphism analysis of e.g. the urease genes. Furthermore, reproducibility, discriminatory power, ease of performance and interpretation, cost and toxic procedures of each method are assessed. To date no direct comparison of all the molecular typing methods described has been performed in the same study with the same H. pylori strains. However, PCR analysis of the urease gene directly on suspensions of H. pylori or gastric biopsy material seems to be useful for routine use and applicable in specific epidemiological situations.

Bacterial Typing Techniques↗
PubMed1998

Ribotyping of strains of Moraxella (Branhamella) catarrhalis cultured from the nasopharynx and middle ear of children with otitis media.

Moraxella (Branhaomella) catarrhalis is frequently present in the nasopharyngeal microflora of small children, especially during episodes of acute otitis media . By means of ribotyping (restriction endonuclease analysis of chromosomal DNA combined with rRNA probing), we studied the genetic heterogeneity of 78 cultures of M. catarrhalis obtained from different localities in the nasopharynx of nine young children with secretory otitis media. Using HindIII and PstI as endonucleases, five different ribotypes were recognized, representing at least five different genotypes of M. catarrhalis. The distribution of these types was found to be almost identical to the distribution among 16 M. catarrhalis strains cultured from middle ear exudates of 16 children with acute otitis media. Ribotype HAPA was found in two-thirds of all the cultures investigated, and 44% of the children harboured more than one ribotype in the nasopharynx at the same time. The vast majority of the nasopharyngeal M. catarrhalis cultures were beta-lactamase positive. One child had both a HAPA ribotype, beta-lactamase-negative strain in the nasopharyngeal secretions, and HAPA ribotype, beta-lactamase-positive strains at the entrance of the eustachian tube, the nasopharyngeal tonsils, the folds of the nasopharyngeal tonsils and the oropharynx. All except one of the M. catarrhalis strains cultured from middle ear exudates were beta-lactamase positive.

Child↗
PubMed1997

Antimicrobial susceptibility testing of 230 Helicobacter pylori strains: importance of medium, inoculum, and incubation time.

No standardized method of susceptibility testing for Helicobacter pylori is currently available, so before a large agar dilution study comprising 230 H. pylori strains belonging to more than 80 genetically different groups was initiated, we performed a relatively small preliminary study to determine the influences of medium, inoculum density, and incubation time. Seven media were investigated and were primarily evaluated on the basis of their abilities to support growth both semiquantitatively and qualitatively; Iso-Sensitest agar supplemented with 10% horse blood was found to be well suited for the purpose; this was closely followed by Mueller-Hinton agar with 10% horse blood, Mueller-Hinton with 10% sheep blood, and finally, 7% lysed horse blood agar. Investigations of two inoculum densities and two incubation times resulted in recommendations for the use of 10(9) CFU/ml (10[6] CFU/spot) as the inoculum and 72 h as the incubation time. A modest inoculum effect was noted for amoxicillin and metronidazole. By the methodology derived from our preliminary study, the susceptibilities of 230 H. pylori strains to six antibiotics were subsequently determined. The results were generally in accord with those of others, and apart from metronidazole, the MIC of which for approximately 25% of the strains tested was >8 microg/ml, resistance was low in Denmark. The situation might, however, quickly change when and if the number of indications for antibiotic therapy for H. pylori infections increase. Consequently, susceptibility testing of all H. pylori strains is recommended in order to survey the development of resistance, and in our hands the described methodology was relatively easy to perform and the results were easy to read.

Animals↗
PubMed1996

Comparison of ribotyping and genome fingerprinting of Pseudomonas aeruginosa isolates from cystic fibrosis patients.

Forty Pseudomonas aeruginosa strains, previously characterized by pulsed-field gel electrophoresis, were ribotyped with EcoRI, BamHI, ClaI, and PvuII. Ribotyping with PvuII proved to be as discriminatory as pulsed-field gel electrophoresis with XbaI or DraI while EcoRI and BamHI were not. ClaI contributed further ribotypes, some of which might be due to a transposable element.

Bacteriological Techniques↗
PubMed1995

Ribotyping on small-sized spirochetes isolated from subgingival plaque.

In the present study DNA restriction patterns and corresponding ribotypes of 17 subgingival small-sized spirochetes (1:2:1 and 2:4:2 isolates), 2 Treponema socranskii strains and two Treponema denticola strains were examined. Purified chromosomal DNA was digested by BamHI, HindIII, PstI and ClaI. The DNA fragments were separated in a horizontal slab of 0.7% agarose containing ethidium bromide and transferred by nylon membranes. Hybridization was carried out with digoxigenin-labelled copy DNA of 16S and 23S ribosomal RNA from Escherichia coli. Depending on the restriction endonuclease used, up to 4 distinct bands were observed for the 2:4:2 isolates and the T. denticola strains. For each of the endonucleases used, identical band patterns were always observed for this group of isolates, and these patterns differed persistently from the T. denticola strains. For the 1:2:1 strains, up to 11 distinct bands were observed after digestion with HindIII, whereas a maximum of 6 bands were observed when PstI or ClaI was used. By using ClaI, the examined 1:2:1 isolates were separated into 8 groups, whereas PstI and HindIII separated these isolates into 5 groups. The ribotyping showed that the tested 1:2:1 spirochetes were more heterogeneous than the 2:4:2 spirochetes examined.

Bacterial Typing Techniques↗
PubMed1995

Restriction fragment length polymorphism of rRNA genes for molecular typing of members of the family Legionellaceae.

Typing of Legionella pneumophila remains important in the investigation of outbreaks of Legionnaires' disease and in the control of organisms contaminating hospital water. We found that the discriminatory power of a nonradioactive ribotyping method could be improved by combining results obtained with four restriction enzymes (HindIII, NciI, ClaI, and PstI). Fifty-eight clinical and environmental L. pneumophila strains including geographically unrelated as well as epidemiologically connected isolates were investigated. Epidemiologically related strains had the same ribotypes independent of the combinations of enzymes used. Some strains belonging to the same serogroup were assigned to different ribotypes, and some ribotypes contained members of different serogroups, indicating, as others have found, that serogroup and genotype are not always related. The discriminatory power of the method was estimated by calculating an index of discrimination (ID) for individual enzymes and combinations thereof. The combined result with all four enzymes was highly discriminatory (ID = 0.97), but results for three enzymes also yielded ID values acceptable for epidemiological purposes. In addition, the testing of 27 type strains and 6 clinical isolates representing Legionella species other than L. pneumophila indicated that ribotyping might be of value for species identification within this genus, as previously suggested.

Bacterial Typing Techniques↗
PubMed1994

Ribotyping for differentiating Flavobacterium meningosepticum isolates from clinical and environmental sources.

On the basis of DNA-DNA hybridization data, two main genomic relatedness groups (I and II) have been reported for a geographically varied collection of 52 strains of Flavobacterium meningosepticum. Herein, we have shown that genomic group II can be further divided into four subgroups (II:1 to II:4). To examine the taxonomic relevance of the ribosomal patterns of the 52 F. meningosepticum strains, the patterns were compared with existing DNA-DNA hybridization data with restriction enzymes PstI and HindIII. Ribotyping of the 52 F. meningosepticum strains showed banding patterns that could identify them correctly to one of the five genomic groups or subgroups. To assess the value of ribotyping for the interpretation of epidemiological data, the discriminatory power of the method was investigated for the 52 F. meningosepticum strains. With one to four restriction enzymes (PstI, HindIII, ClaI, EcoRI), a discriminatory index of 0.95 to 0.97 was found. The value of ribotyping in an epidemiological setting was assessed for three clinical isolates of F. meningosepticum from an outbreak of meningitis and bacteremia in the neonatal intensive care unit, Rigshospitalet, Copenhagen, Denmark. The three clinical isolates were shown to belong to the same ribotype, characteristic of genomic subgroup II:1. This ribotyping method will prove to be a useful tool for epidemiological studies concerning F. meningosepticum in the future.

Bacteremia↗
PubMed1992

Enzymuria in neonates receiving continuous intravenous infusion of gentamicin.

Urinary excretion of the tubular enzymes NAG and AAP was investigated during gentamicin treatment of 105 newborn infants. The values found for NAG and AAP show a significant positive correlation. The urinary excretion of NAG was on the average 92% higher during gentamicin treatment as compared with non-treatment periods in the same newborn infant (33 infants). The same tendency applied to AAP. Newborn infants receiving continuous intravenous infusion of gentamicin were not found to be at greater risk of nephrotoxicity than those receiving intermittent gentamicin treatment, using NAG and AAP as an index of nephrotoxicity. The changes in NAg and AAP within treatment periods were studied. During gentamicin treatment an insignificant average increase in the urinary excretion of NAG occurred, whereas a significant decrease was found during non-treatment periods. A significant negative correlation was found between urinary excretion of NAG and birth weight/gestational age. The long-term effect of the higher excretion of NAG and AAP in newborn and adult patients during aminoglycoside treatment is unknown.

Acetylglucosaminidase↗
PubMed1989

Auditory function after continuous infusion of gentamicin to high-risk newborns.

Audiometry was performed at four years of age in 69 of 105 surviving children who had received continuous intravenous infusion of gentamicin during neonatal intensive care. A hearing loss of 20 dB was found in 2 of them (3%), corresponding to that shown in other studies of survivors following neonatal intensive care. Free field audiometry performed in another 7 children and questionnaires returned from 13 of the remaining 29 gave no suspicion of hearing loss. Thus there is no indication that continuous 24 hours intravenous infusion of gentamicin causes more hearing impairment than intermittent intravenous or intramuscular administration.

Audiometry↗
PubMed1988

Stability of ampicillin, piperacillin, cefotaxime, netilmicin and amikacin in an L-amino acid solution prepared for total parenteral nutrition of newborn infants.

The stability of ampicillin, piperacillin and cefotaxime, alone or in combination with either netilmicin or amikacin, was tested by microbiological methods at 29 degrees C (ampicillin, also at 22 degrees C) in an L-amino acid solution specially prepared for newborn infants. In the case of ampicillin, the mean concentration had dropped to 84% of the initial value after 24 hours. This fall is acceptable. Piperacillin and cefotaxime were stable. Admixture of netilmicin or amikacin did not affect the activity of ampicillin, piperacillin and cefotaxime. The concentrations of netilmicin and amikacin were stable for 24 hours. Combination with ampicillin, piperacillin or cefotaxime did not affect the activity of either aminoglycoside. The antibiotics investigated could therefore be used in our TPN infusion system.

Amikacin↗
PubMed1984

[Erythromycin].

Explore the source record for details and available documents.

Drug Resistance, Microbial↗
PubMed1984

Continuous intravenous infusion of ampicillin and gentamicin during parenteral nutrition to 36 newborn infants using a dosage schedule.

Ampicillin and gentamicin were given continuously i.v. to 36 newborn infants using a dosage schedule and the results were compared with those obtained in an earlier study including 88 infants who received individually calculated dosages. With the dosage schedule the variation in the serum concentrations of antibiotics was smaller in the same child throughout the treatment course, but greater between the infants. The 95% limits for the serum concentrations of antibiotics were, however, nearly the same in the two treatment groups, and the use of a dosage schedule is therefore recommended. Serum gentamicin concentration should be assayed about 3 half lives (18 hours) after beginning the treatment, and dosage adjustment be made if the serum gentamicin concentration is outside 3-5 micrograms/ml.

Ampicillin↗