SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Monsen Tor) "

Sökning: WFRF:(Monsen Tor)

  • Resultat 1-41 av 41
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Ahlm, Clas, 1956-, et al. (författare)
  • Brain abscess caused by methicillin-resistant Staphylococcus aureus
  • 2000
  • Ingår i: Scandinavian Journal of Infectious Diseases. - : Informa UK Limited. - 0036-5548 .- 1651-1980. ; 32:5, s. 562-563
  • Tidskriftsartikel (refereegranskat)abstract
    • A Swedish tourist was admitted to a Cuban hospital due to epileptic seizures caused by brain tumors. Upon return to Sweden and admission to our hospital, methicillin-resistant Staphylococcus aureus (MRSA) was isolated. He was later considered to be free of MRSA but then developed a brain abscess from which MRSA was isolated.
  •  
2.
  •  
3.
  • Falk-Brynhildsen, Karin, 1959- (författare)
  • The effect  of peroperative skin preparation on bacterial growth during cardiac surgery
  • 2013
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Routine products are used and procedures are followed in order to prevent and minimize the bacterial contamination of the surgical wound, and thus reduce the risk of postoperative wound infections. The overall aim of this thesis was to investigate the effect of different preoperative skin preparation before cardiac surgery.In study I, 10 healthy volunteers were compared in time to recolonization of the skin and bacterial growth with or without plastic adhesive drape. Bacterial samples were taken as paired samples on both side of the sternum. Plastic drape on disinfected skin seems to hasten recolonization compared with bare skin.In study II, 135 cardiac surgery patients were comparing plastic adhesive drape versus bare skin on the chest regarding intra-operative bacterial growth. Plastic adhesive drape did not reduce the bacterial recolonization or wound contamination, P. acnes colonizes males more often than females and P. acnes is not affected by disinfection with 0.5% chlorhexidine in ethanol.Study III, compared the leg harvesting site with or without microbal skin sealant in 135 CABG patients regarding intraoperative bacterial growth and postoperative wound infection. Almost no bacterial growth was found during surgery regardless of the use of microbial skin sealant and bare skin. A high incidence of postoperative wound infections (16.8%) in 2 month follow up was present and SSI was largely caused by S. aureus, i.e. other bacterial species than observed intraoperative.Study IV, a descriptive study using phenotypic and genotypic methods investigate susceptibility to chlorhexidine among S. epidermidis indicating that S. epidermidis isolates following preoperative skin disinfection are sensitive tochlorhexidine.
  •  
4.
  • Ferry, Sven A., et al. (författare)
  • High diagnostic accuracy of nitrite test paired with Urine sediment can reduce unnecessary antibiotic therapy
  • 2015
  • Ingår i: Open Microbiology Journal. - : Bentham Science Publishers Ltd.. - 1874-2858. ; 9, s. 150-159
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Urinary tract infections (UTIs) are common bacterial infections dominated by lower UTI in women (LUTIW). Symptoms only are insufficient for diagnosis and accordingly, near patient diagnostic tests confidently confirming significant bacteriuria are desirable. The nitrite test (NIT) has low sensitivity, while bacterial and leukocyte counts disjunctively paired in urine sediment microscopy (SED) have high sensitivity. Similar symptomatic cure rates are found post antibiotic vs. placebo therapy in patients with negative cultures. Consequently, prescription on symptoms only implies unnecessary antibiotic therapy. Aims: to evaluate the diagnostic outcomes of NIT, SED and NIT disjunctively paired with SED (NIT+SED) vs. urine culture, with special focus on bladder incubation time (BIT), and to assess if NIT+SED can reduce unnecessary antibiotic therapy. Methods: A diagnostic, primary care, multicentre study including 1070 women with symptoms suggestive of lower UTI. Results: Significant bacteriuria was found in 77%. The BIT highly influenced the diagnostic outcomes and the optimal duration was ≥4h with sensitivity of 66, 90 and 95% for NIT, SED and NIT+SED, respectively. SED performed only in NIT negative specimens could reduce unnecessary antibiotics by 10% vs. prescription on symptoms only. The number needed to test with SED to reduce one unnecessary antibiotic course was five patients at BIT ≥4h and six patients at ≤3h or overall. Conclusion: The BIT highly influences the diagnostic outcomes with the highest accuracy of NIT+SED. Diagnosis of LUTIW with NIT+SED can reduce unnecessary antibiotic therapy and subsequently decrease antimicrobial resistance. Trial registration: The Swedish Medical Product Agency 1995 03 01:151:01783/94. © 2015, Ferry et al.; Licensee Bentham Open.
  •  
5.
  •  
6.
  •  
7.
  •  
8.
  • Grönqvist, Anders, et al. (författare)
  • Bactericidal effect of pulsed 1,064 nm Nd: YAG laser light on Staphylococcus epidermidis is of photothermal origin : an In Vitro Study
  • 2000
  • Ingår i: Lasers in Surgery and Medicine. - : John Wiley & Sons. - 0196-8092. ; 27:4, s. 336-340
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and Objective: The aim was to investigate the bactericidal effect of the 1,064 nm Nd:YAG laser on Staphylococcus epidermidis.Material and Methods: S. epidermidis was inoculated on agar plates and then exposed to pulsed laser light in three different modes: with an uninterrupted train of pulses, or with two different repeated cycles of fractionated trains of pulses. The agar temperature was measured directly after uninterrupted radiation.Results: A bacterial growth inhibition area of 0.3 cm2 and maximum temperature of approximately 80 degrees C was observed after uninterrupted radiation at 2,000 J cm-2. The corresponding figures after an exposure of 5,000 J cm-2 were 0.9 cm2 and 100 degrees C, respectively. No bacterial inhibition was observed after exposure to repeated cycles of 20 seconds of radiation followed by 60 seconds of rest.Conclusion: The antimicrobial effect of the 1,064 nm Nd:YAG laser light is caused by a photothermal rather than a photochemical effect.
  •  
9.
  • Heinz, Judith, et al. (författare)
  • Strategies to reduce antibiotic use in women with uncomplicated urinary tract infection in primary care : protocol of a systematic review and meta-analysis including individual patient data
  • 2020
  • Ingår i: BMJ Open. - : BMJ Publishing Group Ltd. - 2044-6055. ; 10:10
  • Forskningsöversikt (refereegranskat)abstract
    • Introduction: Uncomplicated urinary tract infection (UTI) in women is a common reason to present in general practice and is usually treated with antibiotics to reduce symptom severity and duration. Results of recent clinical trials indicate that non-antibiotic treatment approaches can also be effective. However, it remains unclear which patients would benefit from antibiotic treatment and which can effectively and safely be treated without antibiotics. This systematic review and meta-analysis aims to estimate the effect of treatment strategies to reduce antibiotic use in comparison with immediate antibiotic treatment and to identify prognostic factors and moderators of treatment effects. A further aim is to identify subgroups of patients benefiting from a specific therapy.Methods and analysis: A systematic literature search will be performed to identify randomised controlled trials which investigated the effect of treatment strategies to reduce antibiotic use in female adults with uncomplicated UTI compared with immediate antibiotic treatment. Therefore, the primary outcome of the meta-analysis is incomplete recovery. Anonymised individual patient data (IPD) will be collected. Aggregate data will be used for pairwise comparisons of treatment strategies using meta-analysis models with random effects accounting for potential between-study heterogeneity. Potential effect moderators will be explored in meta-regressions. For IPD, generalised linear mixed models will be used, which may be adjusted for baseline characteristics. Interactions of baseline variables with treatment effects will be explored. These models will be used to assess direct comparisons of treatment, but might be extended to networks.Ethics and dissemination: The local institutional review and ethics board judged the project a secondary analysis of existing anonymous data which meet the criteria for waiver of ethics review. Dissemination of the results will be via published scientific papers and presentations. Key messages will be promoted for example, via social media or press releases.
  •  
10.
  • Hellmark, Bengt, 1971- (författare)
  • Genotypic and phenotypic characterisation of Staphylococcus epidermidis isolated from prosthetic joint infections
  • 2011
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Staphylococcus epidermidis has emerged in recent years as an important nosocomial pathogen, especially in infections associated with implanted foreign body materials (e.g., prosthetic joints and heart valves) and in individuals with a compromised immune system (e.g., cancer patients and neonates). Although rare, implant infections are long lasting and cause severe suffering for the patient that includes pain and disability and even increased mortality. One aim of the present thesis was to develop and evaluate a genetic method for species identification and simultaneous detection of rifampicin resistance in staphylococci. A second aim was to examine S. epidermidis isolated from prosthetic joint infections (PJIs) and from wrists and nares of healthy individuals regarding their antibiotic susceptibility, biofilm production, virulence factors, and epidemiology. Comparison with phenotypic diagnostics revealed that 8 (16%) of 49 isolates differed in their species identification in favour of the genetic method. In addition, mutations associated with rifampicin resistance, including two not previously reported, were possible to detect in all isolates resistant to rifampicin. Antibiotic susceptibility testing of 61 PJI isolates showed multi-drug resistance in 91%. Furthermore, the results of the synergy testing revealed that no antibiotic combination was significantly better than the others. Hence, the effects that were possible to detect were isolate dependent. To find a method for discriminating between invasive (n=61) and commensal (n=24) isolates of S. epidermidis genotypic and phenotypic characterisations of biofilm production (including the ica and aap genes), antibiotic susceptibility, virulence-related genes (such as agr and ACME) and epidemiology were performed (using multilocus sequence typing [MLST], typing of the staphylococcal chromosome cassette mec [SCCmec] and PhenePlate). Significant differences were found in antibiotic susceptibility, i.e. there was more resistance among invasive isolates. MLST sequence types (ST) ST2 and ST215 dominated the invasive isolates.
  •  
11.
  • Henning, Claes, et al. (författare)
  • Rekommenderade metoder Diagnostik av infektioner i blod orsakade av bakterier och svamp
  • 2024
  • Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
    • I detta dokument beskrivs rekommenderade metoder för blododling inkluderat fungemi(svampinfektion i blod) samt metodik för diagnostik av endokardit och misstanke om infektion relaterad till kärlkatetrar. Rekommendationerna är baserade på internationella riktlinjer och relevant vetenskaplig litteratur. Där det finns icke tillräcklig vetenskapligt stöd har arbetsgruppen antingen avstått från en rekommendation eller givit en rekommendation baserad på de ingående medlemmarnas erfarenhet och kunnande.
  •  
12.
  • Hou, Jiapeng, et al. (författare)
  • Enhanced Antibiotic Tolerance of an In Vitro Multispecies Uropathogen Biofilm Model, Useful for Studies of Catheter-Associated Urinary Tract Infections
  • 2022
  • Ingår i: Microorganisms. - : MDPI. - 2076-2607. ; 10:6
  • Tidskriftsartikel (refereegranskat)abstract
    • Catheter-associated urinary tract infections (CAUTI) are a common clinical concern as they can lead to severe, persistent infections or bacteremia in long-term catheterized patients. This type of CAUTI is difficult to eradicate, as they are caused by multispecies biofilms that may have reduced susceptibility to antibiotics. Many new strategies to tackle CAUTI have been proposed in the past decade, including antibiotic combination treatments, surface modification and probiotic usage. However, those strategies were mainly assessed on mono- or dual-species biofilms that hardly represent the long-term CAUTI cases where, normally, 2–4 or even more species can be involved. We developed a four-species in vitro biofilm model on catheters involving clinical strains of Escherichia coli, Pseudomonas aeruginosa, Klebsiella oxytoca and Proteus mirabilis isolated from indwelling catheters. Interspecies interactions and responses to antibiotics were quantitatively assessed. Collaborative as well as competitive interactions were found among members in our model biofilm and those interactions affected the individual species’ abundances upon exposure to antibiotics as mono-, dual- or multispecies biofilms. Our study shows complex interactions between species during the assessment of CAUTI control strategies for biofilms and highlights the necessity of evaluating treatment and control regimes in a multispecies setting.
  •  
13.
  • Hulterström, Anna Karin, et al. (författare)
  • Bacterial flora and the epidemiology of staphylococcus aureus in the nose among patients with symptomatic nasal septal perforations
  • 2016
  • Ingår i: Acta Oto-Laryngologica. - : Informa UK Limited. - 0001-6489 .- 1651-2251. ; 136:6, s. 620-625
  • Tidskriftsartikel (refereegranskat)abstract
    • Conclusions Patients with symptomatic perforations of the nasal septum had a high prevalence of S. aureus in the nasal mucosa. Pulsed field gel electrophoresis (PFGE) analysis revealed a high genetic heterogeneity of S. aureus among both patients and controls. This indicates that presence of different strains of S. aureus can maintain a chronic inflammation in symptomatic nasal septal perforations. Objective The purpose of this study was to investigate the microbial flora around nasal septal perforations in patients having severe symptoms regarding bleeding, obstruction, and crustation associated with their perforation. Methods Twenty-five patients with untreated symptomatic nasal septal perforations were included. For culture, swabs around the perforations were collected. Bacteria were identified with standard laboratory techniques including a MALDI-TOF mass spectrometer. Epidemiological analysis was done using PFGE protocols. Bacteriological data were compared with data from a healthy control group. Results Staphylococcus aureus was present in the mucosa surrounding the nasal perforation significantly more often (p < 0.0001) in the patients (88%) compared to a control group (13%). Corynebacterium spp. and Propionibacterium spp. were significantly more frequently identified in the control group. The PFGE analysis of S. aureus strains revealed a high genetic heterogeneity and no specific S. aureus genotypes were associated with septal perforation.
  •  
14.
  • Johansson, Anders, 1966-, et al. (författare)
  • Multiple-locus variable-number tandem repeat analysis for typing of Staphylococcus epidermidis.
  • 2006
  • Ingår i: Journal of Clinical Microbiology. - 0095-1137 .- 1098-660X. ; 44:1, s. 260-5
  • Tidskriftsartikel (refereegranskat)abstract
    • We applied a high-resolution PCR-based typing method, multiple-locus variable-number tandem repeat analysis (MLVA), for discrimination of 30 multidrug-resistant clinical isolates of Staphylococcus epidermidis. The results of MLVA were congruent with results obtained by pulsed-field gel electrophoresis (PFGE). MLVA generated discrete character data, and its discriminatory capacity was comparable to that of PFGE.
  •  
15.
  • Kaußner, Yvonne, et al. (författare)
  • Reducing antibiotic use in uncomplicated urinary tract infections in adult women : a systematic review and individual participant data meta-analysis
  • 2022
  • Ingår i: Clinical Microbiology and Infection. - : Elsevier. - 1198-743X .- 1469-0691. ; 28:12, s. 1558-1566
  • Forskningsöversikt (refereegranskat)abstract
    • Background: Randomised controlled trials (RCTs) investigated analgesics, herbal formulations, delayed prescription of antibiotics, and placebo to prevent overprescription of antibiotics in women with uncomplicated urinary tract infections (uUTI).Objectives: To estimate the effect of these strategies and to identify symptoms, signs, or other factors that indicate a benefit from these strategies.Data sources: MEDLINE, EMBASE, Web of Science, LILACS, Cochrane Database of Systematic Reviews and of Controlled Trials, and ClinicalTrials.Study eligibility criteria, participants and interventions: RCTs investigating any strategies to reduce antibiotics vs. immediate antibiotics in adult women with uUTI in primary care.Methods: We extracted individual participant data (IPD) if available, otherwise aggregate data (AD). Bayesian random-effects meta-analysis of the AD was used for pairwise comparisons. Candidate moderators and prognostic indicators of treatment effects were investigated using generalised linear mixed models based on IPD.Results: We analysed IPD of 3524 patients from eight RCTs and AD of 78 patients. Non-antibiotic strategies increased the rates of incomplete recovery (OR 3.0; 95% credible interval (CrI), 1.7–5.5; Bayesian p-value (pB) = 0.0017; τ = 0.6), subsequent antibiotic treatment (OR 3.5; 95% CrI, 2.1–5.8; pB = 0.0003) and pyelonephritis (OR 5.6; 95% CrI, 2.3–13.9; pB = 0.0003). Conversely, they decreased overall antibiotic use by 63%.Patients positive for urinary erythrocytes and urine culture were at increased risk for incomplete recovery (OR 4.7; 95% CrI, 2.1–10.8; pB = 0.0010), but no difference was apparent where both were negative (OR 0.8; 95% CrI, 0.3–2.0; pB = 0.667). In patients treated using non-antibiotic strategies, urinary erythrocytes and positive urine culture were independent prognostic indicators for subsequent antibiotic treatment and pyelonephritis.Conclusions: Compared to immediate antibiotics, non-antibiotic strategies reduce overall antibiotic use but result in poorer clinical outcomes. The presence of erythrocytes and tests to confirm bacteria in urine could be used to target antibiotic prescribing.
  •  
16.
  • Kellgren, Therese, et al. (författare)
  • Completed genome and emergence scenario of the multidrug-resistant nosocomial pathogen Staphylococcus epidermidis ST215
  • 2024
  • Ingår i: BMC Microbiology. - : BioMed Central (BMC). - 1471-2180. ; 24:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: A multidrug-resistant lineage of Staphylococcus epidermidis named ST215 is a common cause of prosthetic joint infections and other deep surgical site infections in Northern Europe, but is not present elsewhere. The increasing resistance among S. epidermidis strains is a global concern. We used whole-genome sequencing to characterize ST215 from healthcare settings.Results: We completed the genome of a ST215 isolate from a Swedish hospital using short and long reads, resulting in a circular 2,676,787 bp chromosome and a 2,326 bp plasmid. The new ST215 genome was placed in phylogenetic context using 1,361 finished public S. epidermidis reference genomes. We generated 10 additional short-read ST215 genomes and 11 short-read genomes of ST2, which is another common multidrug-resistant lineage at the same hospital. We studied recombination’s role in the evolution of ST2 and ST215, and found multiple recombination events averaging 30–50 kb. By comparing the results of antimicrobial susceptibility testing for 31 antimicrobial drugs with the genome content encoding antimicrobial resistance in the ST215 and ST2 isolates, we found highly similar resistance traits between the isolates, with 22 resistance genes being shared between all the ST215 and ST2 genomes. The ST215 genome contained 29 genes that were historically identified as virulence genes of S. epidermidis ST2. We established that in the nucleotide sequence stretches identified as recombination events, virulence genes were overrepresented in ST215, while antibiotic resistance genes were overrepresented in ST2.Conclusions: This study features the extensive antibiotic resistance and virulence gene content in ST215 genomes. ST215 and ST2 lineages have similarly evolved, acquiring resistance and virulence through genomic recombination. The results highlight the threat of new multidrug-resistant S. epidermidis lineages emerging in healthcare settings.
  •  
17.
  •  
18.
  • Lagerqvist, Nina, et al. (författare)
  • Evaluation of 11 SARS-CoV-2 antibody tests by using samples from patients with defined IgG antibody titers
  • 2021
  • Ingår i: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 11:1
  • Tidskriftsartikel (refereegranskat)abstract
    • We evaluated the performance of 11 SARS-CoV-2 antibody tests using a reference set of heat-inactivated samples from 278 unexposed persons and 258 COVID-19 patients, some of whom contributed serial samples. The reference set included samples with a variation in SARS-CoV-2 IgG antibody titers, as determined by an in-house immunofluorescence assay (IFA). The five evaluated rapid diagnostic tests had a specificity of 99.0% and a sensitivity that ranged from 56.3 to 81.6% and decreased with low IFA IgG titers. The specificity was > 99% for five out of six platform-based tests, and when assessed using samples collected ≥ 22 days after symptom onset, two assays had a sensitivity of > 96%. These two assays also detected samples with low IFA titers more frequently than the other assays. In conclusion, the evaluated antibody tests showed a heterogeneity in their performances and only a few tests performed well with samples having low IFA IgG titers, an important aspect for diagnostics and epidemiological investigations.
  •  
19.
  • Monsen, Tor, et al. (författare)
  • A new concept and a comprehensive evaluation of SYSMEX UF-1000i flow cytometer to identify culture-negative urine specimens in patients with UTI
  • 2017
  • Ingår i: European Journal of Clinical Microbiology and Infectious Diseases. - : Springer. - 0934-9723 .- 1435-4373. ; 36:9, s. 1691-1703
  • Tidskriftsartikel (refereegranskat)abstract
    • Urinary tract infections (UTIs) are among the most common bacterial infections in men and urine culture is gold standard for diagnosis. Considering the high prevalence of culture-negative specimens, any method that identifies such specimens is of interest. The aim was to evaluate a new screening concept for flow cytometry analysis (FCA). The outcomes were evaluated against urine culture, uropathogen species and three conventional screening methods. A prospective, consecutive study examined 1,312 urine specimens, collected during January and February 2012. The specimens were analyzed using the Sysmex UF1000i FCA. Based on the FCA data culture negative specimens were identified in a new model by use of linear discriminant analysis (FCA-LDA). In total 1,312 patients were included. In- and outpatients represented 19.6% and 79.4%, respectively; 68.3% of the specimens originated from women. Of the 610 culture-positive specimens, Escherichia coli represented 64%, enterococci 8% and Klebsiella spp. 7%. Screening with FCA-LDA at 95% sensitivity identified 42% (552/1312) as culture negative specimens when UTI was defined according to European guidelines. The proposed screening method was either superior or similar in comparison to the three conventional screening methods. In conclusion, the proposed/suggested and new FCA-LDA screening method was superior or similar to three conventional screening methods. We recommend the proposed screening method to be used in clinic to exclude culture negative specimens, to reduce workload, costs and the turnaround time. In addition, the FCA data may add information that enhance handling and support diagnosis of patients with suspected UTI pending urine culture.
  •  
20.
  • Monsen, Tor, et al. (författare)
  • Flow Cytometry Analysis Using Sysmex UF-1000i Classifies Uropathogens Based on Bacterial, Leukocyte, and Erythrocyte Counts in Urine Specimens among Patients with Urinary Tract Infections
  • 2015
  • Ingår i: Journal of Clinical Microbiology. - 0095-1137 .- 1098-660X. ; 53:2, s. 539-545
  • Tidskriftsartikel (refereegranskat)abstract
    • Urinary tract infections (UTIs) are the second most common bacterial infection. Urine culture is the gold standard for diagnosis, but new techniques, such as flow cytometry analysis (FCA), have been introduced. The aim of the present study was to evaluate FCA characteristics regarding bacteriuria, leukocyturia, and erythrocyturia in relation to cultured uropathogens in specimens from patients with a suspected UTI. We also wanted to evaluate whether the FCA characteristics can identify uropathogens prior to culture. From a prospective study, 1,587 consecutive urine specimens underwent FCA prior to culture during January and February 2012. Outpatients and inpatients (79.6% and 19.4%, respectively) were included, of whom women represented 67.5%. In total, 620 specimens yielded growth, of which Escherichia coli represented 65%, Enterococcus spp.8%, Klebsiella spp. 7%, and Staphylococcus spp. 5%. For the uropathogens, the outcome of FCA was compared against the results for specimens with E. coli and those with a negative culture. E. coli had high bacterial (median, 17,914/mu l), leukocyte (median, 348/mu l), and erythrocyte (median, 23/mu l) counts. With the exception of Klebsiella spp., the majority of the uropathogens had considerable or significantly lower bacterial counts than that of E. coli. High leukocyte counts were found in specimens with Staphylococcus aureus, Proteus mirabilis, Pseudomonas aeruginosa, and group C streptococci. Elevated erythrocyte counts were found for P. vulgaris, P. aeruginosa, and group C streptococci, as well as for Staphylococcus saprophyticus. In essence, FCA adds new information about the bacterial, leukocyte, and erythrocyte counts in urine specimens for different uropathogens. Based on FCA characteristics, uropathogens can be classified and identified prior to culture. E. coli and Klebsiella spp. have similar FCA characteristics.
  •  
21.
  • Monsen, Tor, et al. (författare)
  • In vitro effect of ultrasound on bacteria and suggested protocol for sonication and diagnosis of prosthetic infections
  • 2009
  • Ingår i: Journal of Clinical Microbiology. - 0095-1137 .- 1098-660X. ; 47:8, s. 2496-2501
  • Tidskriftsartikel (refereegranskat)abstract
    • Sonication of implants has been shown to be a promising method for diagnosis of prosthetic infections due to its improved sensitivity, simplicity, and low cost. The aim of the present study was to evaluate the effects of ultrasound performed under different conditions regarding temperature, duration, and composition of sonication tubes on bacterial species often associated with prosthetic infections. We found that ultrasound had an inhibitory effect on bacteria, of which gram-negative bacteria, in particular Escherichia coli, were almost eradicated after 5 min of sonication at 35 degrees C. Gram-positive bacteria were found to be resistant to the effect of ultrasound. Four factors were important for the inhibitory effect of sonication: the type of microorganism, the temperature of the sonication buffer, the duration of exposure to ultrasound (minutes), and the material and composition of the sonication tube in which sonication is performed. On the basis of the results from the present study, we propose a protocol for sonication and recovery of bacteria associated with biofilm on infected implants prior to conventional culture. From the present protocol, we recommend sonication for 7 min at 22 degrees C at the maximum effect which permits survival of gram-negative bacteria.
  •  
22.
  • Monsen, Tor J., et al. (författare)
  • Mecillinam resistance and outcome of pivmecillinam treatment in uncomplicated lower urinary tract infection in women
  • 2014
  • Ingår i: Apmis. - Hoboken : Wiley. - 0903-4641 .- 1600-0463. ; 122:4, s. 317-323
  • Tidskriftsartikel (refereegranskat)abstract
    • Pivmecillinam (PIV) is a first-line antimicrobial for treatment of lower urinary tract infection in women (LUTIW). Mecillinam, the active substance of PIV, is bactericidal mainly against gram-negative uropathogens, whereas gram-positive species are considered intrinsically resistant. However, successful treatment of LUTIW caused by Staphylococcus saprophyticus has been reported, but more rarely for other gram-positive species. The aim of this study was to compare clinical and bacteriological outcome of PIV vs placebo treatment among uropathogens with special focus on mecillinam-resistant isolates. We analysed data from a prospective, multicentre, placebo-controlled, primary health care, therapy study performed in Sweden in 1995-1998 that included 1143 women with symptoms suggestive of LUTIW. Urine cultures were collected and symptoms registered at inclusion and at follow-up visits. Overall, the efficacy of PIV was superior to that of placebo. Clinical and bacteriological outcomes of PIV treatment were similar for S. saprophyticus, Escherichia coli as for most other uropathogens irrespective of their susceptibility to mecillinam. However, the occurrence of enterococci increased nearly fivefold shortly post PIV treatment, although with mild symptoms and a high spontaneous eradication. As susceptibility to mecillinam in vitro did not predict bacteriological and clinical outcome of PIV treatment, we suggest that the present breakpoints for mecillinam should be revised.
  •  
23.
  •  
24.
  •  
25.
  • Nielsen, Karen Leth, et al. (författare)
  • Escherichia coli causing recurrent urinary tract infections: Comparison to non-recurrent isolates and genomic adaptation in recurrent infections
  • 2021
  • Ingår i: Microorganisms. - : MDPI. - 2076-2607. ; 9:7
  • Tidskriftsartikel (refereegranskat)abstract
    • Recurrent urinary tract infection (rUTI) remains a major problem for many women and therefore the pursuit for genomic and phenotypic traits which could define rUTI has been ongoing. The present study applied a genomic approach to investigate recurrent urinary tract infections by comparative analyses of recurrent and non-recurrent Escherichia coli isolates from general practice. From whole-genome sequencing data, phylogenetic clustering and genomic traits were studied on a collection of isolates which caused recurrent infection compared to non-recurrent isolates. In addition, genomic variation between the 1st and following infection was studied on a subset of the isolates. Evidence of limited adaptation between the recurrent infections based on single nucleotide polymorphism analyses with a range of 0–13 non-synonymous single nucleotide polymorphisms (SNPs) between the paired isolates. This included an overrepresentation of SNPs in metabolism genes. We identified several genes which were more common in rUTI isolates, including nine fimbrial genes, however, not significantly after false-discovery rate. Finally, the results show that recurrent isolates of the present dataset are not distinctive by variation in the core genome, and thus, did not cluster distinct from non-rUTI isolates in a SNP phylogeny.
  •  
26.
  • Niemiec, Maria Joanna, et al. (författare)
  • Augmented enterocyte damage during Candida albicans and Proteus mirabilis coinfection
  • 2022
  • Ingår i: Frontiers in Cellular and Infection Microbiology. - : Frontiers Media S.A.. - 2235-2988. ; 12
  • Tidskriftsartikel (refereegranskat)abstract
    • The human gut acts as the main reservoir of microbes and a relevant source of life-threatening infections, especially in immunocompromised patients. There, the opportunistic fungal pathogen Candida albicans adapts to the host environment and additionally interacts with residing bacteria. We investigated fungal-bacterial interactions by coinfecting enterocytes with the yeast Candida albicans and the Gram-negative bacterium Proteus mirabilis resulting in enhanced host cell damage. This synergistic effect was conserved across different P. mirabilis isolates and occurred also with non-albicans Candida species and C. albicans mutants defective in filamentation or candidalysin production. Using bacterial deletion mutants, we identified the P. mirabilis hemolysin HpmA to be the key effector for host cell destruction. Spatially separated coinfections demonstrated that synergism between Candida and Proteus is induced by contact, but also by soluble factors. Specifically, we identified Candida-mediated glucose consumption and farnesol production as potential triggers for Proteus virulence. In summary, our study demonstrates that coinfection of enterocytes with C. albicans and P. mirabilis can result in increased host cell damage which is mediated by bacterial virulence factors as a result of fungal niche modification via nutrient consumption and production of soluble factors. This supports the notion that certain fungal-bacterial combinations have the potential to result in enhanced virulence in niches such as the gut and might therefore promote translocation and dissemination.
  •  
27.
  • Saffari, Fereshteh, et al. (författare)
  • Molecular and Phenotypic Characterization of Multidrug-Resistant Clones of Staphylococcus epidermidis in Iranian Hospitals : Clonal Relatedness to Healthcare-Associated Methicillin-Resistant Isolates in Northern Europe
  • 2016
  • Ingår i: Microbial Drug Resistance. - : Mary Ann Liebert Inc. - 1076-6294 .- 1931-8448. ; 22:7, s. 570-577
  • Tidskriftsartikel (refereegranskat)abstract
    • The aim of the study was to investigate the molecular epidemiology of Staphylococcus epidermidis in Iranian hospitals and to compare the genotypes with a previously characterized collection of >1,300 S. epidermidis isolates of nosocomial and community origin from Northern Europe, Australia, and USA. In total, 82 clinical S. epidermidis isolates from three Iranian hospitals were examined by multilocus sequence typing, pulsed-field gel electrophoresis (PFGE) and staphylococcal cassette chromosome mec (SCCmec) typing. In addition, antimicrobial susceptibility, the presence of the ica operon, and the predilection to biofilm formation were assessed. Three predominant PFGE clones were found. The PFGE patterns of the most common sequence type (PFGE type 040-ST2) showed 80% similarity to multidrug-resistant S. epidermidis (MDRSE) clinical isolates from eight hospitals in Northern Europe. The second most common (PFGE 024-ST22) showed an unique PFGE pattern, whereas the third most predominant genotype (PFGE 011-ST5) proved indistinguishable to the PFGE Co-ST5 identified in five hospitals in Northern Europe. In conclusion, the study documented the dissemination of three MDRSE clones within and between hospitals in Iran and revealed an intercontinental spread of two clonal multidrug-resistant lineages (ST2 and ST5) in the hospital environment. Isolates of the predominant clones were significantly more frequently associated with multidrug-resistance and biofilm formation compared to nonclonal isolates. Further studies are needed to explore and characterize the genetic traits that enable these successful MDRSE clones to persist and disseminate worldwide in the healthcare settings.
  •  
28.
  • Saffari, Fereshteh, et al. (författare)
  • Significant spread of extensively drug-resistant Acinetobacter baumannii genotypes of clonal complex 92 among intensive care unit patients in a university hospital in southern Iran
  • 2017
  • Ingår i: Journal of Medical Microbiology. - : MICROBIOLOGY SOC. - 0022-2615 .- 1473-5644. ; 66:11, s. 1656-1662
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: Infections associated with Acinetobacter baumannii represent an increasing threat in healthcare settings. Therefore, we investigated the epidemiological relationship between clinical isolates of A. baumannii obtained from patients in a university hospital in Bandar Abbas in southern Iran.Methodology: Sixty-four consecutive non-duplicate clinical isolates collected during 2014–2015 were subjected to susceptibility testing, clonal relationship analysis using PFGE, multilocus variable-number tandem-repeat analysis (MLVA) and multilocus sequence typing (MLST), and examined for the presence of carbapenemases and integrons.Results: Almost all A. baumannii isolates were extensively drug-resistant (XDR; 98 %) and carried an OXA carbapenemase gene (bla OXA-23-like; 98 %) and class 1 integrons (48 %). PFGE and MLST analysis identified three major genotypes, all belonging to clonal complex 92 (CC92): sequence type 848 (ST848) (n=23), ST451 (n=16) and ST195 (n=8). CC92 has previously been documented in the hospital setting in northern Iran, and ST195 has been reported in Arab States of the Persian Gulf. These data suggest national and global transmission of A. baumannii CC92.Conclusion: This report demonstrates the occurrence and potential spread of closely related XDR genotypes of A. baumannii CC92 within a university hospital in southern Iran. These genotypes were found in the majority of the investigated isolates, showed high prevalence of blaOXA-23 and integron class 1, and were associated with stay in the intensive care unit. Very few treatment options remain for healthcare-adapted XDR A. baumannii, and hence effective measures are desperately needed to reduce the spread of these strains and resultant infections in the healthcare setting.
  •  
29.
  • Waller, K. Persson, et al. (författare)
  • Genotypic characterization of Staphylococcus chromogenes and Staphylococcus simulans from Swedish cases of bovine subclinical mastitis
  • 2023
  • Ingår i: Journal of Dairy Science. - : American Dairy Science Association. - 0022-0302 .- 1525-3198. ; 106:11, s. 7991-8004
  • Tidskriftsartikel (refereegranskat)abstract
    • Staphylococcus chromogenes and Staphylococcus simulans are commonly found in intramammary infections (IMI) associated with bovine subclinical mastitis, but little is known about genotypic variation and relatedness within species. This includes knowledge about genes encoding antimicrobial resistance (AMR) and potential virulence factors (pVF). The aim of this study was therefore to investigate these aspects by whole-genome sequencing of milk isolates from Swedish dairy cows with subclinical mastitis in an observational study. We also wanted to study if specific genotypes were associated with persistent IMI and the inflammatory response at udder quarter level. In total, 105 and 118 isolates of S. chromogenes and S. simulans, respectively, were included. Isolates were characterized using a 7-locus multilocus sequence typing (7-MLST), core genome analysis and in-silico analysis of AMR and pVF genes. Forty-seven sequence types (ST) and 7 core genome clusters of S. chromogenes were identified, and the most common ST were ST-6 and ST-109, both belonging to cluster VII. A 7-locus MLST scheme for S. simulans was not available, but 3 core genome clusters and 5 subclusters were described. Overall, substantial variation in ST and clusters among cows and herds were found in both species. Some ST of S. chromogenes were found in several herds, indicating spread between herds. Moreover, within-herd spread of the same genotype was observed for both species. Only a few AMR genes (blaZ, strpS194, vga(A)) were detected in a limited number of isolates, with the exception of blaZ coding for β-lactamase, which was identified in 22% of the isolates of S. chromogenes with ST-19, ST-102, and ST-103 more commonly carrying this gene compared with other STs. However, the blaZ gene was not identified in S. simulans. The average total number of pVF detected per isolate was similar in S. chromogenes (n = 30) and S. simulans (n = 33), but some variation in total numbers and presence of specific pVF or functional groups of pVF, was shown between ST/clusters within species. Differences in inflammatory response and potentially in persistent IMI at udder quarter level were found between S. chromogenes subtypes but not between S. simulans subtypes. In conclusion, the results from the present study generates new insight into the epidemiology of bovine S. chromogenes and S. simulans IMI, which can have implications for future prevention and antimicrobial treatment of infections related to these species.
  •  
30.
  • Widerstrom, Micael, et al. (författare)
  • Coagulase-negative staphylococci : update on the molecular epidemiology and clinical presentation, with a focus on Staphylococcus epidermidis and Staphylococcus saprophyticus
  • 2012
  • Ingår i: European Journal of Clinical Microbiology and Infectious Diseases. - New York : Springer-Verlag New York. - 0934-9723 .- 1435-4373. ; 31:1, s. 7-20
  • Forskningsöversikt (refereegranskat)abstract
    • Coagulase-negative staphylococci (CoNS), originally described as ubiquitous commensals of the healthy human skin and mucosa, have emerged as important opportunistic pathogens primarily causing healthcare-associated infections in patients with indwelling medical devices. Recent studies, utilizing new molecular typing methods, particularly on Staphylococcus epidermidis, have increased our understanding of the mechanisms that contribute to the evolutionary success of these extremely versatile microorganisms. In the following mini-review, we summarize recent research in this area focusing on the molecular methods and epidemiology of S. epidermidis and S. saprophyticus.
  •  
31.
  • Widerström, Micael, et al. (författare)
  • A Multidrug-Resistant Staphylococcus epidermidis Clone (ST2) Is an Ongoing Cause of Hospital-Acquired Infection in a Western Australian Hospital
  • 2012
  • Ingår i: Journal of Clinical Microbiology. - 0095-1137 .- 1098-660X. ; 50:6, s. 2147-2151
  • Tidskriftsartikel (refereegranskat)abstract
    • We report the molecular epidemiology of 27 clinical multidrug-resistant Staphylococcus epidermidis (MDRSE) isolates collected between 2003 and 2007 in an Australian teaching hospital. The dominant genotype (sequence type 2 [ST2]) accounted for 85% of the isolates tested and was indistinguishable from an MDRSE genotype identified in European hospitals, which may indicate that highly adaptable health care-associated genotypes of S. epidermidis have emerged and disseminated worldwide in the health care setting.
  •  
32.
  • Widerström, Micael, 1958-, et al. (författare)
  • Clonality among multidrug-resistant hospital-associated Staphylococcus epidermidis in northern Europe
  • 2009
  • Ingår i: Scandinavian Journal of Infectious Diseases. - : Informa UK Limited. - 0036-5548 .- 1651-1980. ; 41:9, s. 642-649
  • Tidskriftsartikel (refereegranskat)abstract
    • Using pulsed-field gel electrophoresis (PFGE) we have previously described the occurrence and possible dissemination of a clone of multidrug-resistant Staphylococcus epidermidis (MDRSE) in 2 hospitals in northern Sweden during 2001-2003. The aims of the present study were to investigate if this clone still persisted, 7 y later, in these 2 hospitals and whether this specific clone was detectable among clinical isolates from 9 other hospitals, 6 Swedish as well as a Norwegian, Danish and a German hospital. In total, 173 clinical isolates of MDRSE isolated during 2003 to 2008 were analysed using PFGE, of which 22 isolates were also characterized by multilocus sequence typing (MLST). Two dominating PFGE types (types A and B) were identified, consisting of 56 (32%) and 38 (22%) isolates, respectively. Type A, which was detected in the Norwegian and all Swedish hospitals, proved indistinguishable to the clone previously identified in 2001-2003 and corresponded with a novel sequence type (ST215). Type B was discovered in the German, Danish and in 7 Swedish hospitals and corresponded with ST2. In conclusion, we have demonstrated the occurrence, persistence and potential dissemination of 2 MDRSE genotypes, including a novel sequence type (ST215), within hospitals in northern Europe.
  •  
33.
  • Widerström, Micael, et al. (författare)
  • Colonization of patients, healthcare workers, and the environment with healthcare-associated Staphylococcus epidermidis genotypes in an intensive care unit : a prospective observational cohort study
  • 2016
  • Ingår i: BMC Infectious Diseases. - : Springer Science and Business Media LLC. - 1471-2334. ; 16
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: During the last decades, healthcare-associated genotypes of methicillin-resistant Staphylococcus epidermidis (HA-MRSE) have been established as important opportunistic pathogens. However, data on potential reservoirs on HA-MRSE is limited. The aim of the present study was to investigate the dynamics and to which extent HA-MRSE genotypes colonize patients, healthcare workers (HCWs) and the environment in an intensive care unit (ICU).Methods: Over 12 months in 2006-2007, swab samples were obtained from patients admitted directly from the community to the ICU and patients transferred from a referral hospital, as well as from HCWs, and the ICU environment. Patients were sampled every third day during hospitalization. Antibiotic susceptibility testing was performed according to EUCAST guidelines. Pulsed-field gel electrophoresis and multilocus sequence typing were used to determine the genetic relatedness of a subset of MRSE isolates.Results: We identified 620 MRSE isolates from 570 cultures obtained from 37 HCWs, 14 patients, and 14 environmental surfaces in the ICU. HA-MRSE genotypes were identified at admission in only one of the nine patients admitted directly from the community, of which the majority subsequently were colonized by HA-MRSE genotypes within 3 days during hospitalization. Almost all (89%) of HCWs were nasal carriers of HA-MRSE genotypes. Similarly, a significant proportion of patients transferred from the referral hospital and fomites in the ICU were widely colonized with HA-MRSE genotypes.Conclusions: Patients transferred from a referral hospital, HCWs, and the hospital environment serve as important reservoirs for HA-MRSE. These observations highlight the need for implementation of effective infection prevention and control measures aiming at reducing HA-MRSE transmission in the healthcare setting.
  •  
34.
  • Widerström, Micael, 1958-, et al. (författare)
  • Heterogeneity of Staphylococcus epidermidis in prosthetic joint infections : time to reevaluate microbiological criteria?
  • 2022
  • Ingår i: European Journal of Clinical Microbiology and Infectious Diseases. - : Springer. - 0934-9723 .- 1435-4373. ; 41, s. 87-97
  • Tidskriftsartikel (refereegranskat)abstract
    • Prosthetic joint infection (PJI) is a feared and challenging to diagnose complication after arthroplasty, with Staphylococcus epidermidis as the major pathogen. One important criteria to define PJI is the detection of phenotypically indistinguishable microorganisms with identical antibiotic susceptibility pattern in at least two different samples. However, owing to phenotypical variation within genetic clones and clonal variation within a phenotype, the criteria may be ambiguous. We investigated the extent of diversity among coagulase-negative staphylococci (CoNS) in PJI and characterised S. epidermidis isolates from PJI samples, specifically multiple S. epidermidis isolates identified in individual PJI patients. We performed a retrospective cohort study on 62 consecutive patients with PJI caused by CoNS from two hospitals in Northern Sweden. In 16/62 (26%) PJIs, multiple S. epidermidis isolates were available for whole-genome analyses. Hospital-adapted multidrug-resistant genetic clones of S. epidermidis were identified in samples from 40/62 (65%) of the patients using a combination of pulsed-field gel electrophoresis and multilocus sequence typing. Whole-genome sequencing showed the presence of multiple sequence types (STs) in 7/16 (44%) PJIs where multiple S. epidermidis isolates were available. Within-patient phenotypical variation in the antibiotic susceptibility and/or whole-genome antibiotic resistance gene content was frequent (11/16, 69%) among isolates with the same ST. The results highlight the ambiguity of S. epidermidis phenotypic characterisation as a diagnostic method in PJI and call for larger systematic studies for determining the frequency of CoNS diversity in PJIs, the implications of such diversity for microbiological diagnostics, and the therapeutic outcomes in patients.
  •  
35.
  • Widerström, Micael, 1958- (författare)
  • Molecular epidemiology of coagulase-negative staphylococci in hospitals and in the community
  • 2010
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Background Coagulase-negative staphylococci (CoNS) and in particular Staphylococcus epidermidis have emerged as major pathogens primarily causing nosocomial infections in patients with indwelling medical devices. These infections are often caused by multidrug-resistant strains of S. epidermidis (MDRSE). Other clinical entities due to CoNS are lower urinary tract infections (UTI) in women and native valve endocarditis. The purpose of this work was to investigate the frequency of antibiotic resistance and the molecular epidemiology of both hospital and community-associated isolates of S. epidermidis in order to examine if certain clones are related to MDRSE infections. Furthermore, we aimed to explore if specific clones of S. saprophyticus are associated with UTI in women. Methods A total of 359 hospital-associated methicillin-resistant isolates of CoNS obtained from 11 hospitals in northern Europe and 223 community-associated staphylococcal isolates were examined. Furthermore, 126 isolates of S. saprophyticus isolated from women with uncomplicated UTI from five different locations in northern Europe were analyzed. Pulsed-field gel electrophoresis (PFGE) was used for genotyping. Additionally, some of the S. epidermidis isolates were analyzed with multilocus sequence typing (MLST). Antibiotic susceptibility was determined for all isolates by the disc diffusion test. Results 293 of the 359 (82%) hospital-associated and 124 of the 223 (56%) community-associated isolates belonged to the species S. epidermidis. Among the hospital-associated S. epidermidis isolates, two dominating PFGE types (type A and B) were distinguished, comprising 78 (27%) and 51 (17%) isolates, respectively. Type A, which was detected in a Norwegian and eight Swedish hospitals, corresponded with a novel sequence type (ST215). Type B was discovered in a German, a Danish and seven Swedish hospitals and corresponded with ST2. In contrast, community-associated isolates of S. epidermidis were genetically extremely diverse with no predominating genotype, and showed a low rate of antibiotic resistance; only two (1.6%) methicillin-resistant strains were detected. Among 126 analyzed isolates of S. saprophyticus, 47 different PFGE profiles were identified. Several clusters of genetically highly related isolates were detected among isolates obtained from different locations and periods of time. Conclusion We have demonstrated the occurrence, persistence and potential dissemination of two multidrug-resistant S. epidermidis (MDRSE) genotypes, including a novel sequence type (ST215), within hospitals in northern Europe. Community-associated isolates of S. epidermidis showed a low rate of methicillin-resistance and were genetically heterogeneous. These results indicate that MDRSE by large are confined to the hospital setting in our region. Moreover, although the S. saprophyticus population was quite heterogeneous, indistinguishable isolates of S. saprophyticus causing lower UTI in women were identified in different countries 11 years apart, indicating the persistence and geographical spread of some clones of S. saprophyticus.
  •  
36.
  • Widerström, Micael, 1958-, et al. (författare)
  • Molecular epidemiology of meticillin-resistant coagulase-negative staphylococci in a Swedish county hospital : evidence of intra- and interhospital clonal spread
  • 2006
  • Ingår i: Journal of Hospital Infection. - : Elsevier BV. - 0195-6701 .- 1532-2939. ; 64:2, s. 177-183
  • Tidskriftsartikel (refereegranskat)abstract
    • During a 10-month period in 2003, consecutive routine clinical cultures from patients treated in 15 different ward units in a Swedish county hospital were screened for the presence of meticillin-resistant coagulase-negative staphylococci (CNS). Genetic similarity between isolates was analysed using pulsed-field gel electrophoresis (PFGE). The results were compared with multi-drug-resistant Staphylococcus epidermidis isolated previously at the tertiary referral hospital. In total, 428 isolates of CNS were identified, of which 188 (44%) were meticillin resistant. Three clusters (Groups A, B and C) of S. epidermidis, each consisting of more than 10 isolates, with a PFGE-DNA similarity of >90% were identified. The strains in Groups A and B (N=15 and N=13, respectively), which were generally resistant to gentamicin, co-trimoxazole and clindamycin, originated from 24 patients, of whom 21 had been treated in the intensive care unit (ICU) before sampling. The third cluster, Group C, involved 14 isolates from 14 patients. Only two of these patients had stayed at the ICU, and all for less than one day. Isolates in Group C were less resistant than those in Groups A and B. Isolates belonging to Group A showed an identical PFGE profile compared with multi-drug-resistant S. epidermidis isolated from patients at the referral hospital. This study demonstrated the persistence and spread of meticillin-resistant clones of CNS within the county hospital, especially in the ICU, and possible interhospital spread of a multi-drug-resistant clone between the county and referral hospitals.
  •  
37.
  • Widerström, Micael, 1958-, et al. (författare)
  • Molecular epidemiology of Staphylococcus saprophyticus isolated from women with uncomplicated community-acquired urinary tract infection
  • 2007
  • Ingår i: Journal of Clinical Microbiology. - 0095-1137 .- 1098-660X. ; 45:5, s. 1561-1564
  • Tidskriftsartikel (refereegranskat)abstract
    • Staphylococcus saprophyticus is a common cause of urinary tract infections (UTIs) in women. Little is known about the molecular epidemiology of S. saprophyticus UTIs. In the current study, we compared 76 isolates of S. saprophyticus prospectively isolated from women with uncomplicated UTI participating in a randomized placebo-controlled treatment trial performed in northern Sweden from 1995 to 1997 with 50 strains obtained in 2006 from five different locations in northern Europe with pulsed-field gel electrophoresis (PFGE). The aim was to elucidate the molecular epidemiology of this uropathogenic species and to investigate whether specific clones are associated with UTI in women. A total of 47 different PFGE profiles were detected among the 126 analyzed isolates. Ten clusters consisting of 5 to 12 isolates each showing PFGE DNA similarity of >85% were identified. Several clusters of genetically highly related isolates were detected in the original trial as well as among isolates obtained during 2006 from different locations. In the original trial, clonal persistence was found among 16 of 21 (76%) patients examined in the placebo group at follow-up 8 to 10 days after inclusion, indicating a low spontaneous short-time bacteriological cure rate. We conclude that multiple clones of S. saprophyticus were causing lower UTIs in women. The result suggests that some human-pathogenic clones of S. saprophyticus are spread over large geographical distances and that such clones may persist over long periods of time.
  •  
38.
  • Widerström, Micael, 1958-, et al. (författare)
  • Near absence of methicillin-resistance and pronounced genetic diversity among Staphylococcus epidermidis isolated from healthy persons in northern Sweden
  • 2011
  • Ingår i: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS). - : Wiley-Blackwell. - 0903-4641 .- 1600-0463. ; 119:8, s. 505-512
  • Tidskriftsartikel (refereegranskat)abstract
    • The main aim of the study was to examine if hospital-associated clones of multidrug-resistant Staphylococcus epidermidis (MDRSE), commonly identified in hospitals in our region, also are spread among healthy persons in the community. A total of 124 isolates of S. epidermidis sampled from subjects attending a Travel health clinic, Umeå, Sweden during 2008 were examined with antibiotic susceptibility testing and pulsed field gel electrophoresis (PFGE) analysis. Resistance to methicillin or any antibiotic was detected in two and 26 of the isolates, respectively. PFGE analysis showed an extensive genetic diversity with 86 different PFGE types, of whom 62 were singletons. No isolates belonged to the previously described hospital-associated MDRSE genotypes, indicating that MDRSE by large are confined to the hospital setting in our region. In conclusion, community-associated isolates of S. epidermidis showed a low level of methicillin-resistance and were genetically extremely diverse with no predominating genotype.
  •  
39.
  • Wigren, Julia, et al. (författare)
  • At-home sampling to meet geographical challenges for serological assessment of SARS-CoV-2 exposure in a rural region of northern Sweden, March to May 2021 : a retrospective cohort study
  • 2023
  • Ingår i: Eurosurveillance. - : European Centre for Disease Control and Prevention (ECDC). - 1025-496X .- 1560-7917. ; 28:13
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: The current SARS-CoV-2 pandemic has highlighted a need for easy and safe blood sampling in combination with accurate serological methodology. Venipuncture for testing is usually performed by trained staff at healthcare centres. Long travel distances to healthcare centres in rural regions may introduce a bias of testing towards relatively large communities with closer access. Rural regions are therefore often not represented in population-based data.Aim: The aim of this retrospective cohort study was to develop and implement a strategy for at-home testing in a rural region of Sweden during spring 2021, and to evaluate its role to provide equal health care for its inhabitants.Methods: We developed a sensitive method to measure antibodies to the S-protein of SARS-CoV-2 and optimised this assay for clinical use together with a strategy of at-home capillary blood sampling.Results: We demonstrated that our ELISA gave comparable results after analysis of capillary blood or serum from SARS-CoV-2-experienced individuals. We demonstrated stability of the assay under conditions that reflected temperature and humidity during winter or summer. By assessment of capillary blood samples from 4,122 individuals, we could show both feasibility of the strategy and that implementation shifted the geographical spread of testing in favour of rural areas.Conclusion: Implementation of at-home sampling enabled citizens living in remote rural areas access to centralised and sensitive laboratory antibody tests. The strategy for testing used here could therefore enable disease control authorities to get rapid access to information concerning immunity to infectious diseases, even across vast geographical distance.
  •  
40.
  • Wistrand, Camilla, 1970- (författare)
  • Swedish operating room nurses preventive interventions to reduce bacterial growth, surgical site infections, and increase comfort in patients undergoing surgery
  • 2017
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Surgical site infection is a major postoperative complication that causes patient suffering and is costly for society. The general aim of this thesis was to test and describe interventions performed by operating room (OR) nurses to prevent bacterial growth in surgical patients, with the intent to prevent surgical site infections (SSIs) whilst increase patients comfort.In studies I and II, 220 pacemaker patients were tested to compare pre-heated skin disinfection with room-temperature skin disinfection regard-ing bacterial growth, skin temperature and patient experience. Preheated skin disinfection was not less effective compared to room-temperature skin disinfection in reducing bacterial growth after skin disinfection and there were no differences regarding SSIs three month postoperatively. Preheated skin disinfection reduces skin heat loss and was perceived as more pleas-ant compared to room-temperature skin disinfection.In study III, 12 OR nurses were examined regarding bacterial growth on their hands and at the sterile glove cuff end after surgical hand disinfec-tion and again after wearing sterile surgical gloves during surgery. They were compared with a control group of 13 non-health care workers. OR nurses’ hands had higher amounts of bacterial growth at two of three culture sites after surgical hand disinfection compared with the control group, and the bacterial growth increased in both groups with time during surgery. There seems to be a risk of bacterial growth at the glove cuff end during surgery, involving the same type of bacteria as isolated from the hands.In study IV, 890 OR nurses answered an online questionnaire describ-ing OR nurses interventions guided by national guidelines to reduce SSIs, such as preparation of the patient skin, patient temperature, and OR ma-terials used. The proportion of the OR nurses who complied with the national guidelines preventive interventions was high: skin disinfection solution (93.5%), drapes (97.4%) and gowns (83.8%), and double gloves (73%). However, when guidelines were lacking the interventions differed.
  •  
41.
  • Zhao, Hongxing, et al. (författare)
  • Detection of SARS-CoV-2 antibodies in serum and dried blood spot samples of vaccinated individuals using a sensitive homogeneous proximity extension assay.
  • 2022
  • Ingår i: New biotechnology. - : Elsevier BV. - 1871-6784 .- 1876-4347. ; 72, s. 139-148
  • Tidskriftsartikel (refereegranskat)abstract
    • A homogeneous PCR-based assay for sensitive and specific detection of antibodies in serum or dried blood spots (DBS) is presented and the method is used to monitor individuals infected with or vaccinated against SARS-CoV-2. Detection probes were prepared by conjugating the recombinant spike protein subunit 1 (S1), containing the receptor binding domain (RBD) of SARS-CoV-2, to each of a pair of specific oligonucleotides. The same was done for the nucleocapsid protein (NP). Upon incubation with serum or DBS samples, the bi- or multivalency of the antibodies (IgG, IgA or IgM) brings pairs of viral proteins with their conjugated oligonucleotides in proximity, allowing the antibodies to be detected by a modified proximity extension assay (PEA). Anti-S1 and anti-NP antibodies could be detected simultaneously from one incubation reaction. This Antibody PEA (AbPEA) test uses only 1µl of neat or up to 100,000-fold diluted serum or one ø1.2mm disc cut from a DBS. All 100 investigated sera and 21 DBS collected prior to the COVID-19 outbreak were negative, demonstrating a 100% specificity. The area under the curve, as evaluated by Receiver Operating Characteristic (ROC) analysis reached 0.998 (95%CI: 0.993-1) for samples taken from 11 days after symptoms onset. The kinetics of antibody responses were monitored after a first and second vaccination using serially collected DBS from 14 individuals. AbPEA offers highly specific and sensitive solution-phase antibody detection without requirement for secondary antibodies, no elution step when using DBS sample in a simple procedure that lends itself to multiplex survey of antibody responses.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-41 av 41
Typ av publikation
tidskriftsartikel (32)
doktorsavhandling (4)
forskningsöversikt (3)
annan publikation (2)
Typ av innehåll
refereegranskat (34)
övrigt vetenskapligt/konstnärligt (7)
Författare/redaktör
Monsen, Tor (23)
Widerström, Micael, ... (9)
Wiström, Johan, 1949 ... (6)
Rydén, Patrik (4)
Olsen, Björn (3)
Holm, Stig, 1933 (3)
visa fler...
Stenlund, Hans (2)
Ahlm, Clas, 1956- (2)
Forsell, Mattias N. ... (2)
Heinz, Judith (2)
Kim, H. (1)
Nilsson, Emma (1)
Nilsson, Charlotta (1)
Jönsson, Bodil (1)
Evander, Magnus (1)
Cava, Felipe (1)
Landegren, Ulf (1)
Kamali-Moghaddam, Ma ... (1)
Lindqvist, Per (1)
Dillner, Joakim (1)
Marklund, Elisabeth (1)
Ahlm, Clas (1)
Sellin, Mats (1)
Berggren, Diana (1)
Sjödin, Andreas (1)
Koskinen, Lars Ove (1)
Koskinen, Lars-Owe D (1)
Elgh, Fredrik, 1957- (1)
Söderquist, Bo, Prof ... (1)
Söderquist, Bo (1)
Hellmark, Bengt, 197 ... (1)
Normark, Johan (1)
Lilje, Berit (1)
Överby, Anna K. (1)
Löf, Liza (1)
Sjöstedt, Anders (1)
Rover, Christian (1)
Bogdanovic, Gordana (1)
Kjerstadius, Torbjör ... (1)
Åberg, Mikael (1)
Lagerqvist, Nina (1)
Verner-Carlsson, Jen ... (1)
Olofsson, K (1)
Alm, Martin (1)
Mei, Ya-Fang (1)
Sjöstedt, Anders, Pr ... (1)
Axner, Ove (1)
Muschiol, Sandra (1)
Gallini, Radiosa (1)
McInerney, Gerald (1)
visa färre...
Lärosäte
Umeå universitet (35)
Göteborgs universitet (5)
Örebro universitet (4)
Linnéuniversitetet (2)
Karolinska Institutet (2)
Uppsala universitet (1)
visa fler...
Linköpings universitet (1)
visa färre...
Språk
Engelska (39)
Svenska (2)
Forskningsämne (UKÄ/SCB)
Medicin och hälsovetenskap (32)
Naturvetenskap (8)
Samhällsvetenskap (1)

År

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy