| 1. |
- Hadad, Ronza, 1984-, et al.
(författare)
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Novel meningococcal 4CMenB vaccine antigens : prevalence and polymorphisms of the encoding genes in Neisseria gonorrhoeae
- 2012
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Ingår i: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS). - : Wiley-Blackwell. - 0903-4641 .- 1600-0463. ; 120:9, s. 750-760
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Tidskriftsartikel (refereegranskat)abstract
- The first cross-protective Neisseria meningitidis vaccine (focus on serogroup B), the protein-based 4 component meningococcus serogroup B (4CMenB), includes the New Zealand outer membrane vesicle and three main genome-derived neisserial antigens (GNAs). These GNAs are fHbp (fused to GNA2091), NHBA (fused to GNA1030) and NadA. In this study, the prevalence and polymorphisms of the nucleotide and amino acid sequences of the 4CMenB antigens in a temporally and geographically diverse collection of N. gonorrhoeae isolates (n similar to=similar to 111) were investigated. All the examined GNA genes, except the nadA gene, were present in all gonococcal isolates. However, 25 isolates contained premature stop codons in the fHbp gene and/or the nhba gene, resulting in truncated proteins. Compared with the 4CMenB antigen sequences in reference strain MC58, the gonococcal strains displayed 67.095.4% and 60.994.9% identity in nucleotide sequence and amino acid sequence, respectively, in the equivalent GNA antigens. The absence of NadA, lack of universal expression of fHbp and NHBA and the uncertainty regarding the surface exposure of fHbp as well as the function of NHBA in N. gonorrhoeae will likely limit the use of the identical 4CMenB antigens in a gonococcal vaccine. However, possible cross-immunity of 4CMenB with gonococci and expression and function of the equivalent gonococcal GNAs, as well as of more appropriate GNAs for a gonococcal vaccine, need to be further examined.
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| 2. |
- Golparian, Daniel, 1984-, et al.
(författare)
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Analytical specificity and sensitivity of the novel dual-target GeneProof Neisseria gonorrhoeae PCR kit for detection of N-gonorrhoeae
- 2015
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Ingår i: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS). - : Wiley-Blackwell. - 0903-4641 .- 1600-0463. ; 123:11, s. 955-958
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Tidskriftsartikel (refereegranskat)abstract
- Detection of Neisseria gonorrhoeae relies increasingly on nucleic acid amplification tests (NAATs). The specificity of many gonococcal NAATs has been suboptimal and supplementary testing remains recommended in Europe and several additional countries. The novel dual-target GeneProofNeisseria gonorrhoeae PCR kit, targeting porA pseudogene and 16S rRNA gene, showed a high specificity and sensitivity when isolates of non-gonococcal Neisseria and related species (n=144), and gonococci (n=104) were tested. However, rare gonococcal porA mutants were only detected in the 16S rRNA gene target and two non-gonococcal isolates showed a low-level cross-reactivity in the 16S rRNA gene target. The detection limit for both targets was 1.5 copies per reaction.
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| 3. |
- Hadad, Ronza, 1984-, et al.
(författare)
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Protection against genital tract Chlamydia trachomatis infection following intranasal immunization with a novel recombinant MOMP VS2/4 antigen
- 2016
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Ingår i: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS). - Hoboken, USA : Wiley-Blackwell. - 0903-4641 .- 1600-0463. ; 124, s. 1078-1086
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Tidskriftsartikel (refereegranskat)abstract
- The asymptomatic nature of most Chlamydia trachomatis infections and the lack of appropriate effects by current prevention and management call for vaccine development. We evaluated a recombinant subunit vaccine candidate based on the major outer membrane protein variable segments 2 and 4 (MOMP VS2/4). To achieve maximal immunogenicity and ease of production and purification, MOMP VS2/4 was constructed by using highly immunogenic sequences of MOMP only, thereby minimizing the presence of hydrophobic regions, and spacing the immunogenic epitopes with a flexible amino acid sequence. A purification tag was also added. The MOMP VS2/4 was given intranasally, with or without intravaginal boost, with cholera toxin (CT) adjuvant to C57BL/6 mice, which were screened for immunogenicity and protection against a live challenge infection with C. trachomatis serovar D. Bacterial shedding, cell-mediated responses, and antibody responses were monitored. Immunized mice exhibited significantly less bacterial shedding and were better protected against infertility as compared to unimmunized control mice. Immunizations stimulated both systemic and local specific antibody (IgG1, IgG2c, and IgA) responses, and primed T cells that produced interferon-c and interleukins 13 and 17 upon challenge with recall antigen. Thus, MOMP VS2/4, in combination with CT adjuvant, stimulated Th1, Th2, and Th17 effector cells, and generated protective immunity associated with less pathology. We regard MOMP VS2/4 as a promising candidate for further development into a mucosal chlamydial vaccine.
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| 4. |
- Unemo, Magnus, 1970-, et al.
(författare)
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Genetic homogeneity/heterogeneity of Propionibacterium acnes isolated from patients during cardiothoracic reoperation
- 2007
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Ingår i: Anaerobe. - London : Academic Press. - 1075-9964 .- 1095-8274. ; 13:3-4, s. 121-126
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Tidskriftsartikel (refereegranskat)abstract
- Following cardiothoracic surgery, deep sternal wound infection (SWI) remains one of the most severe complications. Recently, Propionibacterium acnes has been suspected as an etiological agent of deep SWI. However, this bacterium constitutes part of the resident micro-flora of the human skin. Consequently, findings of P. acnes in invasive samples are difficult to value. The aims of this study were to develop and optimize a pulsed-field gel electrophoresis (PFGE) protocol for P. acnes, in order to investigate the genetic homogeneity/heterogeneity of P. acnes isolates from multiple tissue samples (predominantly biopsies), collected at different locations, from 12 patients during cardiothoracic reoperation. There were 24 distinguishable PFGE fingerprints identified among the P. acnes isolates (n=54). Five (42%) of the patients carried only isolates that were interpreted as presumably clonally related. From the remaining seven patients, two or three different P. acnes clones were cultured, however, from six of them, the clones were identified in multiple samples. P. acnes may be a relatively frequent etiological agent of postoperative cardiothoracic infections. Existence of several clonally related P. acnes isolates derived from multiple samples from patients suffering from deep SWI after cardiothoracic surgery has not previously been shown.
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| 5. |
- Parihar, Vishal Singh, et al.
(författare)
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Characterization of human invasive isolates of Listeria monocytogenes in Sweden 1986-2007
- 2008
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Ingår i: Foodborne pathogens and disease. - : Mary Ann Liebert. - 1535-3141 .- 1556-7125. ; 5:6, s. 755-761
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Tidskriftsartikel (refereegranskat)abstract
- Since 1986, 68% of the Listeria monocytogenes isolates from human cases of invasive listeriosis in Sweden are available for retrospective studies. The aim of the present study was to characterize 601 human invasive isolates of L. monocytogenes in Sweden from 1986 to 2007 by using serotyping and pulsed-field gel electrophoresis. Since 1996, serovar 4b was permanently reduced to the second or third most common serovar in human cases in Sweden. During the latter period, 2000-2007, only 13% belonged to serovar 4b and 71% to 1/2a. The dendrogram, based on pulsovars, reveals two clusters with different serovars. Cluster 1 exhibits serovars 4b and 1/2b, whereas cluster 2 consists of serovar 1/2a. Serovar 1/2a seems to be more heterogeneous than serovar 4b.
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| 6. |
- Lanjouw, E., et al.
(författare)
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2015 European guideline on the management of Chlamydia trachomatis infections
- 2016
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Ingår i: International Journal of STD and AIDS (London). - London, United Kingdom : Sage Publications. - 0956-4624 .- 1758-1052. ; 27:5, s. 333-348
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Tidskriftsartikel (refereegranskat)abstract
- Chlamydia trachomatis infections, which most frequently are asymptomatic, are major public health concerns globally. The 2015 European C. trachomatis guideline provides: up-to-date guidance regarding broader indications for testing and treatment of C. trachomatis infections; a clearer recommendation of using exclusively-validated nucleic acid amplification tests for diagnosis; advice on (repeated) C. trachomatis testing; the recommendation of increased testing to reduce the incidence of pelvic inflammatory disease and prevent exposure to infection; and recommendations to identify, verify and report C. trachomatis variants. Improvement of access to testing, test performance, diagnostics, antimicrobial treatment and follow-up of C. trachomatis patients are crucial to control its spread. For detailed background, evidence base and discussions, see the background review for the present 2015 European guideline on the management of Chlamydia trachomatis infections (Lanjouw E, etal. Int J STD AIDS. 2015).
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| 7. |
- Wind, Carolien M., et al.
(författare)
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Test of cure for anogenital gonorrhoea using modern RNA-based and DNA-based nucleic acid amplification tests : a prospective cohort study
- 2016
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Ingår i: Clinical Infectious Diseases. - Cary, United Kingdom : Oxford University Press. - 1058-4838 .- 1537-6591. ; 62:11, s. 1348-1355
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Tidskriftsartikel (refereegranskat)abstract
- Background: The use of nucleic acid amplification tests (NAATs) to diagnose Neisseria gonorrhoeae infections complicates the performance of a test of cure (TOC) to monitor treatment failure, if this is indicated. As evidence for the timing of TOC using modern NAATs is limited, we performed a prospective cohort study to assess time to clearance when using modern RNA- and DNA-based NAATs.Methods: We included patients with anogenital gonorrhoea visiting the STI Clinic Amsterdam from March through October 2014. After treatment with ceftriaxone mono- or dual therapy (with azithromycin or doxycycline) anal, vaginal or urine samples were self-collected during 28 consecutive days, and analysed using an RNA-based NAAT (Aptima Combo 2) and a DNA-based NAAT (Cobas 4800). Clearance was defined as three consecutive negative results, and blips as isolated positive results following clearance.Results: We included 77 patients; five self-cleared gonorrhoea before treatment and ten were lost to follow-up. Clearance rate of the remaining 62 patients was 100%. Median time to clearance was two days, with a range of 1-7 days for RNA-based NAAT, and 1-15 days for DNA-based NAAT. The risk of finding a blip after clearance was 0.8% and 1.4%, respectively. One patient had a reinfection.Conclusions: If indicated, we recommend to perform a TOC for anogenital gonorrhoea at least 7 or 14 days after administering therapy, when using modern RNA- or DNA-based NAATs, respectively. When interpreting TOC results for possible treatment failure, both the occurrence of blips and a possible reinfection need to be taken into account.
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| 8. |
- Jensen, Jørgen Skov, et al.
(författare)
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In vitro activity of the first-in-class triazaacenaphthylene gepotidacin alone and in combination with doxycycline against drug-resistant and -susceptible Mycoplasma genitalium
- 2020
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Ingår i: Emerging Microbes & Infections. - : Taylor & Francis. - 2222-1751. ; 9:1, s. 1388-1392
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Tidskriftsartikel (refereegranskat)abstract
- Mycoplasma genitalium has developed resistance to first-line azithromycin and second-line moxifloxacin. Third-line pristinamycin is only 75% effective. Gepotidacin, a novel triazaacenaphthylene topoisomerase II inhibitor, blocks bacterial DNA replication. We determined thein vitroactivity of gepotidacin alone and in combination with doxycycline against a diverse collection of Mycoplasma genitalium isolates (n = 54).Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were determined by a Vero-cell culture method. Macrolide resistance was present in 31 (57%) isolates, fluoroquinolone resistance in 18 (33%) isolates, and 17 (31%) had dual resistance. Synergy testing was performed for gepotidacin and doxycycline by checkerboard analysis for two macrolide- and two dual-resistant isolates.Gepotidacin was active against all 54 M. genitalium isolates with median and modal MICs of 0.125 mg/L and MIC(90)of 0.25 mg/L (range <= 0.016-0.5 mg/L). No difference in gepotidacin MIC between macrolide-resistant and -susceptible isolates (p = 0.24) or between fluoroquinolone-, dual-resistant and -susceptible isolates (p = 0.2) was demonstrated. Gepotidacin MBCs were available for 44 M. genitalium isolates with median MIC of 0.064 mg/L and median MBC of 0.125 mg/L. All isolates had <= 4-fold difference between MIC and MBC, suggesting bactericidal effect for gepotidacin. Checkerboard analysis indicated synergistic effect for gepotidacin in combination with doxycycline [fractional inhibitory concentration index (sigma FICI) of 0.5] for two isolates and additive/indifference (sigma FICI at 0.62 and 0.75) for two isolates.Gepotidacin warrants further evaluation in clinical treatment trials for M. genitalium. Combination therapy with doxycycline should be clinically studied to assess effect and potential protection against development and/or spread of gepotidacin resistance.
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| 9. |
- Rumyantseva, Tatiana, et al.
(författare)
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Evaluation and subsequent optimizations of the quantitative AmpliSens Florocenosis/Bacterial vaginosis-FRT multiplex real-time PCR assay for diagnosis of bacterial vaginosis
- 2016
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Ingår i: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS). - Hoboken, USA : Wiley-Blackwell Publishing Inc.. - 0903-4641 .- 1600-0463. ; 124:12, s. 1099-1108
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Tidskriftsartikel (refereegranskat)abstract
- Traditional microscopy-based methods for diagnosis of bacterial vaginosis (BV) are underutilized in many settings, and molecular techniques may provide opportunities for rapid, objective, and accurate BV diagnosis. This study evaluated the quantitative AmpliSens Florocenosis/Bacterial vaginosis-FRT multiplex real-time PCR (Florocenosis-BV) assay. Vaginal samples from a previous study including unselected female subjects (n = 163) and using Amsel criteria and 454 pyrosequencing for BV diagnosis were examined with the Florocenosis-BV test and additionally tested for the presence and quantity of Gardnerella vaginalis clades 3 and 4. The Florocenosis-BV assay demonstrated 100% and 98% sensitivity compared with the Amsel criteria and 454 pyrosequencing, respectively, with 91% specificity. The modified Florocenosis-BV assay (detecting also G. vaginalis clades 3 and 4) resulted in 100% sensitivity vs the Amsel criteria and 454 pyrosequencing with specificity of 86% and 88%, respectively. Further optimizations of thresholds for the quantitative parameters used in the kit resulted in 99-100% accuracy vs Amsel criteria and 454 pyrosequencing for selected parameters. The Florocenosis-BV assay is an objective, accurate, sensitive, and specific method for BV diagnosis; however, the performance of the test can be further improved with some minor optimizations.
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| 10. |
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