Biomedical subjects

Christina Welinder-Olsson

Publications and source records attributed to Christina Welinder-Olsson.

10 recordsLinked to original sources

PubMed2006

Cutaneous melioidosis in a Swedish tourist after the tsunami in 2004.

A tourist from Sweden developed cutaneous melioidosis after the tsunami in Thailand on 26 December 2004. Melioidosis is a severe, chronic infection which is endemic in Thailand and is caused by Burkholderia pseudomallei. Persons with traumatic injuries inflicted by the tsunami have increased risks of being infected by B. pseudomallei and melioidosis should be suspected if abscesses of the skin or inner organs develop in the months or years after the trauma.

Anti-Bacterial Agents↗

PubMed2006

Description of Pseudochrobactrum gen. nov., with the two species Pseudochrobactrum asaccharolyticum sp. nov. and Pseudochrobactrum saccharolyticum sp. nov.

Two Gram-negative, rod-shaped, oxidase-positive, non-spore-forming, non-motile bacteria (CCUG 46016(T) and CCUG 33852(T)), isolated from a knee aspirate of a 66-year-old man and an industrial glue, respectively, were studied for their taxonomic position. On the basis of chemotaxonomic data [i.e. major ubiquinone (Q-10), major polar lipids (phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine) and major fatty acids (C(18 : 1)omega7c and C(19 : 0) cyclo omega8c)] and 16S rRNA gene sequence similarity, both strains belong to the Alphaproteobacteria. The presence of spermidine and putrescine as the predominant polyamines in CCUG 46016(T) were in agreement with its phylogenetic affiliation in the vicinity of the genus Ochrobactrum. 16S rRNA gene sequence similarities between both strains and established species within the genera Bartonella, Ochrobactrum and Brucella were less than 95 %. Although both organisms showed highest 16S rRNA gene sequence similarity to members of Brucella, phenotypic features (including chemotaxonomic features) were more like those of members of the genus Ochrobactrum. Sequence comparison of the recA genes confirmed the separate phylogenetic position of the two strains. On the basis of DNA-DNA pairing results and physiological and biochemical data, the two strains can be clearly differentiated from each other and from all known Ochrobactrum species. It is evident that these organisms represent two novel species in a new genus, Pseudochrobactrum gen. nov., for which the names Pseudochrobactrum asaccharolyticum sp. nov. (the type species, type strain CCUG 46016(T)=CIP 108977(T)) and Pseudochrobactrum saccharolyticum sp. nov. (type strain CCUG 33852(T)=CIP 108976(T)) are proposed.

Adhesives↗

PubMed2005

Enterohemorrhagic Escherichia coli (EHEC).

Enterohaemorrhagic Escherichia coli has since the last 2 decades been known to cause severe and bloody diarrhoea as well as haemorrhagic colitis (HC) and haemorrhagic uraemic syndrome (HUS) especially among children. The importance of screening for EHEC among children and older patients with severe symptoms is apparent. Production of the verocytotoxins VT1 and VT2 are the main features of EHEC, and the VT types and mode of action during human infection is described. There are, however, other features adding to the pathogenicity. In this review we deal with the importance of properties such as fimbriae and adhesins as well as systems to meet the bacterial need for iron during infection. These factors are probably important for the establishment of EHEC in the gut and add to the bacterial virulence. It has now become evident that VT producing E. coli, irrespective of serogroup, might be human pathogens. We conclude that knowledge of the different possible virulence factors adds to the possibility of separating more virulent from less virulent isolates.

Animals↗

PubMed2005

Fastidiosipila sanguinis gen. nov., sp. nov., a new Gram-positive, coccus-shaped organism from human blood.

Phenotypic and phylogenetic studies were performed on two strains of an unidentified Gram-positive, fastidious, non-spore-forming, coccus-shaped bacterium recovered from human blood. The organism was catalase-negative and grew under strictly anaerobic conditions and in the presence of 2 and 6 % O(2). Comparative 16S rRNA gene sequencing demonstrated that the unidentified bacterium was, phylogenetically, far removed from peptostreptococci and related Gram-positive coccus-shaped organisms, but exhibited a phylogenetic association with Clostridium rRNA cluster III [as defined by Collins et al., Int J Syst Bacteriol 44 (1994), 812-826]. Sequence divergence values of 15 % or more were observed between the unidentified bacterium and all other recognized species within this and related rRNA clostridial clusters. Treeing analysis showed that the unknown bacterium formed a deep line branching at the periphery of rRNA cluster III and represents a hitherto unknown genus within this supra-generic grouping. On the basis of both phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium from blood be classified in a new genus, Fastidiosipila gen. nov., as Fastidiosipila sanguinis sp. nov. The type strain of Fastidiosipila sanguinis is CCUG 47711(T) (=CIP 108292(T)).

Aged↗

PubMed2004

Detection of bacterial DNA in painful degenerated spinal discs in patients without signs of clinical infection.

A local inflammatory and potentially painful response, of which the ultimate cause is unknown, has been described in nervous tissues in contact with degenerated disc material in patients with low back and leg pain. With the rationale that a possible cause of such inflammation could be bacterial infection, we utilized PCR (polymerase chain reaction) amplification of the 16S rRNA (ribosomal RNA) gene followed by gene sequencing, to investigate whether bacterial DNA might be detected in the degenerative discs of 10 patients operated for disc herniation or post-discectomy syndrome. One patient with disc hernia harbored DNA homologous to Bacillus cereus, and in one patient suffering from post-discectomy syndrome, Citrobacter braaki/freundii DNA was detected. The finding demonstrates that 16S rRNA PCR can be a useful tool in search of bacterial DNA in degenerated discs, which in turn may be indicative of low-grade infection, manifesting itself only as pain rather than as clinical infection.

Adult↗

PubMed2004

Streptococcus devriesei sp. nov., from equine teeth.

Phenotypic and phylogenetic studies were performed on four unidentified Gram-positive staining, catalase-negative, alpha-hemolytic Streptococcus-like organisms recovered from the teeth of horses. SDS PAGE analysis of whole-cell proteins and comparative 16S rRNA gene sequencing demonstrated the four strains were highly related to each other but that they did not correspond to any recognised species of the genus Streptococcus. Phylogenetic analysis based on 16S rRNA gene sequences showed the unidentified organisms form a hitherto unknown sub-line within the Streptococcus genus, displaying a close affinity with Streptococcus mutans, Streptococcus ferus and related organisms. Sequence divergence values of > 5% with these and other reference streptococcal species however demonstrated the organisms from equine sources represent a novel species. Based on the phenotypic distinctiveness of the new bacterium and molecular chemical and molecular genetic evidence, it is proposed that the unknown species be classified as Streptococcus devriesei sp. nov. The type strain of Streptococcus devriesei is CCUG 47155T (= CIP 107809T).

Animals↗

PubMed2004

Arsenicicoccus bolidensis gen. nov., sp. nov., a novel actinomycete isolated from contaminated lake sediment.

An unknown Gram-positive, catalase-positive, facultatively anaerobic, non-spore-forming, coccus-shaped bacterium originating from sediment was characterized using phenotypic, molecular chemical and molecular phylogenetic methods. Chemical studies revealed the presence of a cell-wall murein based on LL-diaminopimelic acid (type LL-Dpm-glycine(1)), a complex mixture of saturated, monounsaturated and iso- and anteiso-methyl-branched, non-hydroxylated, long-chain cellular fatty acids and tetrahydrogenated menaquinones with eight isoprene units [MK-8(H(4))] as the major respiratory lipoquinone. This combination of characteristics somewhat resembled members of the suborder Micrococcineae, but did not correspond to any currently described species. Comparative 16S rRNA gene sequencing confirmed that the unidentified coccus-shaped organism is a member of the Actinobacteria and represents a hitherto-unknown subline related to, albeit different from, a number of taxa including Intrasporangium, Janibacter, Terrabacter, Terracoccus and Ornithinicoccus. Based on phenotypic and phylogenetic considerations, it is proposed that the unknown bacterium originating from lake sediment be classified as a new genus and species, Arsenicicoccus bolidensis gen. nov., sp. nov. (type strain CCUG 47306(T)=DSM 15745(T)).

Actinomycetales↗

PubMed2004

16S rDNA PCR analysis of infectious keratitis: a case series.

PURPOSE: To discuss the value of polymerase chain reaction (PCR) in the management of bacterial infectious keratitis. METHODS: Corneal scrapings of four patients with severe infectious keratitis were analysed by culture and PCR of 16S ribosomal DNA (rDNA), followed by direct sequencing of the resulting amplicon. The medical history of the patients included laser-assisted in-situ keratomileusis (LASIK), penetrating keratoplasty (PKP) and trauma. RESULTS: Using PCR we were able to identify a possible pathogen in all four cases, while bacterial cultures were either negative or did not correspond to the clinical picture. The identified bacteria were a Pseudomonas species, Abiotrophia defectiva, Stenotrophomonas maltophilia and Porphyromonas gingivalis. CONCLUSIONS: Analysis of corneal scrapings by 16S rDNA PCR should be considered as a supplement to standard microbiological procedures. However, the results of this relatively new method have to be interpreted carefully.

Adult↗

PubMed2002

[How an outbreak of MRSA in Gothenburg was eliminated: by strict hygienic routines and massive control-culture program].

The largest single-strain outbreak of methicillin resistant Staphylococcus aureus (MRSA) in Scandinavia so far occurred at Sahlgrenska University Hospital in Western Sweden 1997-2000. The strain identified was identical to the UK EMRSA-16 strain. 147 patients at 36 different wards became colonised or infected. Established routines for infection control had to be revised. The endemic situation necessitated an MRSA screening programme in October 1999 for all former hospital patients on re-admission. Since May 2000 no patient has been found with the outbreak strain at Sahlgrenska University Hospital.

Adolescent↗

PubMed2002

Genetic profiling of enterohemorrhagic Escherichia coli strains in relation to clonality and clinical signs of infection.

Sixty-seven human strains of enterohemorrhagic Escherichia coli (EHEC) (from patients with more or less severe symptoms) were serogrouped and arranged according to pulsed-field gel electrophoresis (PFGE) patterns. We used PCR to investigate the strains according to known or putative virulence factors, and associations with disease were studied. All EHEC strains with the same PFGE pattern belonged to the same serogroup. On the contrary, two serogroups (O157 and O8) included strains with different PFGE patterns. We found several different combinations of chromosomal and plasmid-borne determinants, encoding the putative virulence factors, among the strains. As judged from clinical symptoms, there was no marked difference in pathogenicity among the strains and their combinations of virulence traits. All strains of O157 had the genes coding for verocytotoxin (VT) 2, intimin (eaeA), E. coli hemolysin (E-hly), and secreted serine protease (espP). Among EHEC non-O157 strains, the genes coding for VT1 and VT2 were equally dispersed. EaeA positivity was just as common among VT1- as VT2-positive strains. Among the plasmid-borne determinants, E-hly and espP were the most common and E-hly might be a pathogenicity marker among EHEC non-O157 strains. The conclusion is that PFGE is a very useful tool in epidemiological studies. The EHEC plasmids are heterogeneous in their gene composition, with the four plasmid-borne determinants found in many combinations. There was no reliable correlation between chromosomal and plasmid-borne virulence factors and human disease.

Adolescent↗