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H Westh

Publications and source records attributed to H Westh.

At least 19 recordsLinked to original sources
PubMed2006

Excretion patterns of human metapneumovirus and respiratory syncytial virus among young children.

BACKGROUND: As respiratory syncytial virus (RSV) and human metapneumovirus (hMPV) cause serious respiratory tract infections, the routes of transmission of these viruses are important to elucidate. We examined the modes of virus shedding and shedding duration of RSV and hMPV in young children. METHODS: From each child in a group of 44 children (37 RSV-positive, 6 hMPV-positive, and 1 co-infected child), aged between 0.5-38 months, hospitalised at Hvidovre Hospital, Copenhagen, Denmark, one nasopharyngeal aspirate (NPA), saliva, urine, and faeces sample were collected at inclusion and weekly in a three-week period. Sweat and blood samples were obtained at inclusion. The presence of RSV and hMPV RNA was detected using real-time RT-PCR. RESULTS: We detected RSV RNA in 28 saliva specimens, 5 stool samples, and 3 sweat samples. hMPV RNA was detected in one saliva specimen and two sweat samples. Four of the five children shedding RNA in faeces had diarrhoea and children shedding RNA in sweat were either less than five weeks of age or had a chronic lung disease. RSV and hMPV RNA was shed in nasal secretions for a median of 11.5 and 5.0 days respectively (p = 0.001). More than 75% of the family members of the infected children showed to have an upper respiratory tract infection when following up. CONCLUSION: Viral RNA was present in nasal secretions, saliva, sweat, and faeces, but whether or not the virions were infectious and constitute a potential mode of transmission remains to be shown in future studies.

Acute Disease↗
PubMed2006

Origins and evolution of methicillin-resistant Staphylococcus aureus clonal lineages.

Most methicillin-resistant Staphylococcus aureus (MRSA) isolates identified among blood isolates collected in Denmark between 1957 and 1970 belonged to either phage group III or the closely related 83A complex and had a PSTM antibiotype (resistance to penicillin [P], streptomycin [S], tetracycline [T], and methicillin [M]). Recently, some of these isolates were shown to have the same genetic backgrounds as contemporary epidemic MRSA isolates, and Danish methicillin-susceptible S. aureus (MSSA) isolates from the 1960s with a PST antibiotype were proposed to have been the recipients of the mecA gene in those lineages. In this study, we investigated the genetic backgrounds of isolates from the 83A complex that were fully susceptible or resistant to penicillin only in order to try to trace the evolutionary trajectory of contemporary MRSA lineages. We also studied MSSA and MRSA isolates from other phage groups in order to investigate if they had the potential to develop into contemporary MRSA clones. Most susceptible or penicillin-resistant isolates from phage group III or the 83A complex belonged to sequence type 8 (ST8) or ST5, while four isolates were ST254. STs 30, 45 and 25 were represented by MSSA isolates from other phage groups, which also included several singletons. Representatives of most of the current major epidemic MRSA lineages were identified among fully susceptible isolates collected in the 1960s, suggesting that these were MSSA lineages which carried genetic traits important for superior epidemicity before the acquisition of methicillin resistance.

Anti-Bacterial Agents↗
PubMed2006

High interlaboratory reproducibility of DNA sequence-based typing of bacteria in a multicenter study.

Current DNA amplification-based typing methods for bacterial pathogens often lack interlaboratory reproducibility. In this international study, DNA sequence-based typing of the Staphylococcus aureus protein A gene (spa, 110 to 422 bp) showed 100% intra- and interlaboratory reproducibility without extensive harmonization of protocols for 30 blind-coded S. aureus DNA samples sent to 10 laboratories. Specialized software for automated sequence analysis ensured a common typing nomenclature.

Bacterial Typing Techniques↗
PubMed2004

The most common chromosome aberration detected by high-resolution comparative genomic hybridization in vulvar intraepithelial neoplasia is not seen in vulvar squamous cell carcinoma.

We analyzed genetic changes in condylomas (four cases), vulvar intraepithelial neoplasia I-III (VIN I-III, eleven cases), and primary vulvar squamous cell carcinomas (VSCC, ten cases) by high-resolution comparative genomic hybridization (HR-CGH) and flowcytometry. All samples were also human papilloma virus (HPV)-genotyped. Gain of chromosome 1, the aberration most often seen in VIN III (67%), was not seen in HPV-positive or -negative VSCCs (0%). Both VIN III and VSCC frequently showed gain of 3q (56 and 70%, respectively). The VIN III samples often demonstrated gain of 20q (56%) and 20p (44%), and the VSCC samples gain of 8q (60%), loss of 3p (50%), and 8p (40%). None of the four most frequent changes in the VSCC samples occurred exclusively in the HPV-positive or -negative samples. As expected, we did not find any cytogenetic changes in condylomas and nearly any changes in VIN I-II.

Adult↗
PubMed2003

Large-scale testing of women in Copenhagen has not reduced the prevalence of Chlamydia trachomatis infections.

OBJECTIVE: To examine the impact of a stable, large-scale enzyme immunoassay (EIA) Chlamydia trachomatis testing situation in Copenhagen, and to estimate the impact of introducing a genomic-based assay with higher sensitivity and specificity. METHODS: Over a five-year study period, 25 305-28 505 women screened for chlamydial infection each year, corresponding to 19.3% of the female population in Copenhagen, Denmark, were analyzed. RESULTS: The C. trachomatis age-specific examination percentage and age-specific positive percentage were unchanged during the study period. For EIA, the age-specific positive predictive value of a test decreased from 94% at age 17 to only 50% at age 34 years. Irrespective of the choice of diagnostic test, only about 30% of chlamydial infections would be diagnosed, given current strategies. CONCLUSION: Although genomic detection assays will increase the positive and negative predictive values of the Chlamydia test result, new screening strategies for both men and women in younger age groups will be necessary if chlamydial infections are to be curtailed.

Adolescent↗
PubMed2003

Comparison of the Becton Dickinson strand displacement amplification and Cobas Amplicor Roche PCR for the detection of Chlamydia trachomatis: pooling versus individual tests.

The objective of the study was to examine the influence of pooling Chlamydia trachomatis specimens. We compared Becton Dickinson ProbeTec strand displacement amplification (SDA) with Cobas Amplicor Roche (PCR). With PCR as the standard, SDA performed equally well in single-sample testing. For pooled PCR samples (compared to individual PCR), we found a sensitivity of 100% and a specificity of 98.9%. For pooled SDA tests (compared to individual SDA), we found a sensitivity of 86.5% and a specificity of 98.9%. Our conclusion is that 2-sucrose phosphate buffer (2-SP) can be used for individual SDA testing. A reduced sensitivity was found for pooled SDA samples, and we cannot recommend that SDA be used for pooling with 2-SP. Further pooling studies with other transport media are warranted.

Adolescent↗
PubMed2001

The evolution of methicillin resistance in Staphylococcus aureus: similarity of genetic backgrounds in historically early methicillin-susceptible and -resistant isolates and contemporary epidemic clones.

The key genetic component of methicillin resistance, the mecA determinant, is not native to Staphylococcus aureus. Thus, the evolution of methicillin-resistant S. aureus (MRSA) must have begun with the acquisition of the mecA determinant from an unknown heterologous source some time before the first reported appearance of MRSA isolates in clinical specimens in the U.K. and Denmark (in the early 1960s). We compared the genetic backgrounds and phenotypes of a group of methicillin-susceptible S. aureus (MSSA) isolates to the properties of MRSA strains isolated in Denmark and the U.K. during the same time period, and also to the genetic profiles of contemporary epidemic clones of MRSA. All early MRSA isolates resembled a large group of the early MSSA blood isolates in phenotypic and genetic properties, including phage group, antibiotype (resistance to penicillin, streptomycin, and tetracycline), pulsed-field gel electrophoresis pattern, and spaA type and multilocus sequence type, strongly suggesting that the early MSSA examined here represented the progeny of a strain that served as one of the first S. aureus recipients of the methicillin-resistance determinant in Europe. The genetic background of this group of early MSSA isolates was also very similar to that of the widely disseminated contemporary "Iberian clone" of MRSA, suggesting that genetic determinants present in early MSSA and essential for some aspects of the epidemicity and/or virulence of these strains may have been retained by this highly successful contemporary MRSA lineage.

Amino Acid Sequence↗
PubMed2001

[Cases of measles in Denmark are caused by reintroduction of virus from abroad].

Measles vaccination was implemented in the child vaccination programme in Denmark in 1987 and produced a rapid decline in the incidence. Few cases were recorded annually until 1999. The measles virus isolated in Denmark during 1997-1998 was compared by partial sequencing of the haemagglutinin-coding region with Danish strains from the prevaccination era collected in 1965-1983, as well as with representatives of globally circulating strains of today. The dissimilarity of the prevaccination era strains identified in Denmark in 1997-1998 along with the similarity of these five strains with globally circulating strains at present, substantiate the conclusion that there is no persistent circulation of the measles virus in Denmark.

Child↗
PubMed2000

Sequence analysis of the hemagglutinin gene of measles virus isolates in Denmark 1997-1998: no evidence of persistent circulation of measles virus in Denmark.

The hemagglutinin-coding region of 17 virus samples from 12 measles cases in Denmark during 1997-1998 was analysed by partial nucleotide sequencing. The cases appeared as three sporadic cases and two epidemics, both with a limited time course and geographical distribution. The measles strains identified from the three sporadic cases and two epidemics could be allocated to five different previously well-defined sequence groups consistent with the assumption that cases of measles in Denmark are due to repeated introduction from abroad rather than persistent circulation of strains in the population.

Antibodies, Viral↗
PubMed2000

Archaic strains of methicillin-resistant Staphylococcus aureus: molecular and microbiological properties of isolates from the 1960s in Denmark.

Methicillin-resistant Staphylococcus aureus (MRSA) isolated in the 1960s in Denmark are among the historically earliest samples of these bacteria. We determined microbiological and molecular properties of 46 such isolates. They showed remarkably uniform properties, which included: (i) low methicillin MIC value (6-25 microg/ml); (ii) heterogeneous expression of resistance; (iii) the presence of a single, common, mecA polymorph II; (iv) lack of the regulatory gene mecI; (v) frequent lack of Tn554; and (vi) a common pulsed-field gel electrophoresis (PFGE) type. These properties, together with the chronological dates of isolation, and recovery of the strains from 18 hospitals scattered over Denmark, suggest that they represent a lineage close in time to the evolutionary origin of European strains of MRSA.

Anti-Bacterial Agents↗
PubMed1999

Structural alterations in the translational attenuator of constitutively expressed ermC genes.

Sequence deletions of 16, 59, and 111 bp as well as a tandem duplication of 272 bp with respect to the corresponding sequence of pT48 were identified in the regulatory regions of constitutively expressed ermC genes. Constitutive ermC gene expression as a consequence of these structural alterations is based on either the prevention of the formation of mRNA secondary structures in the translational attenuator or the preferential formation of those mRNA secondary structures which do not interfere with the translation of the ermC transcripts. A model for the development of sequence deletions in the ermC translational attenuator by homologous recombination is presented and experimentally tested by in vitro selection of constitutively expressed mutants in staphylococcal strains deficient and proficient in homologous recombination.

Animals↗
PubMed1998

[Penicillin resistant pneumococci--not a threat in Denmark yet?].

The occurrence of penicillin resistance in clinical isolates of pneumococci was investigated in two clinical microbiological laboratories in Copenhagen, Denmark. One of the laboratories predominantly received samples from patients with frequent use of antibiotics mainly because of chronic lung diseases. In this laboratory, 6.3% of 245 isolates of pneumococci had intermediate resistance to penicillin. In the other laboratory, which received samples from a number of hospitals and general practice, only 1.3% of isolates of pneumococci had reduced sensitivity to penicillin. Penicillin-resistant pneumococci are rare in Denmark, but are more prevalent in patients who frequently use antibiotics.

Adult↗
PubMed1998

Ulcer bed infection. Report of a case of enlarging venous leg ulcer colonized by Pseudomonas aeruginosa.

We report a case of ulcer bed infection in an enlarging venous leg ulcer without clinical signs of cellulitis in the surrounding tissues. Signs of infection in the leg ulcer were: 1) cocci-like structures and bacteria-like rods around vessel walls in the viable ulcer bed, 2) vasculitis-like inflammation of deeply situated vessels of the viable tissue, 3) Pseudomonas aeruginosa-specific antibodies in the serum (other than against exotoxin A), 4) extensive epidermolysis of normal human skin by the wound exudate in vitro, and 5) P. aeruginosa exotoxin A in the wound exudate (23 ng/ml). In an in vitro cell assay, the wound exudate was cytotoxic and rabbit antibodies to exotoxin A, but not a serine proteinase inhibitor, inhibited this cytotoxicity. P. aeruginosa exotoxin A might contribute to the pathogenesis of the ulcer enlargement. The ulcer improved after the third skin graft, probably mainly due to effective treatment with a long-stretch compression bandage.

ADP Ribose Transferases↗