bluuebunny/crossref_metadata_2025_split huggingface dataset:
O3-S5.02 Frequent breakthrough genital HSV-2 shedding on standard and high dose valacyclovir
Authors: Johnston C , Saracino M , Kuntz S , Magaret A , Schiffer J T , Selke S , Huang Meei-li , Corey L , Wald A 
Published: July 2011

BackgroundShort, rapidly cleared, subclinical shedding episodes are the predominant form of HSV-2 reactivation in the genital tract. Valacyclovir 500 mg once daily (SD-VAL) reduces the risk of sexual transmission of herpes simplex virus type 2 (HSV-2) by only 48%. We hypothesised that short HSV-2 shedding episodes occur frequently on SD-VAL and that high dose (HD)-VAL could suppress such episodes of genital HSV-2 shedding.MethodsA randomised open-label crossover study using valacyclovir 500 mg daily (SD-VAL) vs valacyclovir 1 gm three times daily (HD-VAL) was conducted in HSV-2 seropositive, HIV seronegative persons with four or more genital herpes recurrences per year or laboratory confirmed primary genital HSV-2 infection in the previous 6 months. Each study arm lasted for 5 weeks, separated by 1 week wash out. Participants obtained genital swabs four times daily, which were assayed for HSV by quantitative PCR. The primary outcome was frequency of genital HSV shedding on each study arm; secondary outcomes included number and duration of HSV-2 shedding episodes and quantity of virus detected.ResultsForty-three participants collected 9981 genital swabs during the study period. 292 (5.8%) of 5008 swabs had HSV detected during SD-VAL, compared to 164 (3.3%) of 4973 on HD-VAL (IRR=0.52, 95% CI=0.43% to 0.63%, p<0.001). Episodes were shorter on HD-VAL (median 7 h, compared to 10 h on SD-VAL, p=0.03) and the median maximum copy number was lower on HD-VAL (3.0 log10 copy/ml vs 2.5 log10 copies/ml, p=0.001). However, the annual episode rate was the same regardless of dose; there were 55 shedding episodes over 3.89 person-years of follow-up during SD-VAL (14.1 episodes/year) and 65 episodes over 3.93 person-years during HD-VAL (16.5 episodes/year, p=0.34).ConclusionShort bursts of genital HSV-2 reactivation persist during SD-VAL and HD-VAL. Compared to SD-VAL, HD-VAL decreased shedding frequency and episode duration but did not alter episode rate. These data may explain why risk of HSV transmission and HSV-specific genital inflammation persist even in the presence of antiviral therapy. More potent therapies are needed to completely suppress HSV-2 reactivationClinicalTrials.gov numberNCT00362297.
O1-S03.01 Antimicrobial resistance toNeisseria gonorrhoeain a cohort of young men in Kisumu, Kenya: 2002–2009
Authors: Mehta S , Maclean I , Ndinya-Achola J , Murugu R , Agunda L , Ronald A , Martin I , Bailey R , Moses S , Melendez J , Zenilman J 
Published: July 2011

BackgroundWe evaluated antimicrobial resistance inNeisseria gonorrhoeae(NG) isolated from men aged 18–24 enrolled in a randomised trial of male circumcision to prevent HIV.MethodsUrethral specimens were obtained from men with discharge. These were inoculated in modified Thayer-Martin agar and incubated at 37°C in 5% CO2for 24–48 h, with confirmation of NG colonies by standard procedures. Minimum inhibitory concentrations (MICs) were determined by agar dilution. Clinical Laboratory Standards Institute criteria determined resistance: MIC≥2.0 μg/ml for penicillin, tetracycline, and azithromycin; ciprofloxacin MIC≥1.0 μg/ml; spectinomycin MIC≥128.0 μg/ml. Susceptibility to ceftriaxone and cefixime was MIC<0.25 μg/ml. We used PCR amplification to detect mutations in the parC and gyrA genes, associated with quinolone resistance.ResultsFrom 2002 to 2009, 168 NG isolates were obtained from 142 men. Plasmid mediated penicillin resistance (PPNG) was found in 65%, plasmid mediated tetracycline resistance (TRNG) in 97%, and 11% were ciprofloxacin resistant (QRNG). QRNG appeared November 2007, increasing from 9.5% in 2007 to 50% in 2009 see Abstract O1-S03.01 table 1. Resistance was not detected for spectinomycin, cefixime, ceftriaxone, and azithromycin, but MICs of cefixime (p=0.018), ceftriaxone (p<0.001), and azithromycin (p=0.097) increased over time. In a random sample of 51 men gentamicin MIC was assessed: 4 μg/ml (n=1), 8 μg/ml (n=49), 16 μg/ml (n=1). Increased MICs were associated with urban residence, multiple recent sex partners, not using condoms.Abstract O1-S03.01 Table 1YearQuinolone resistance n/N (%)95% CI2002–20060/89 (0.0)–20072/21 (9.5)1.2 to 30.420086/22 (27.3)10.7 to 50.220097/14 (50.0)23.0 to 77.0p Value for trend<0.001ConclusionsQuinolone resistance increased rapidly and alternative treatment, such as cefixime, is required for NG in this area. Systematic surveillance of antimicrobial resistance in NG is necessary for appropriate drug choice. Increases in MICs for oral cephalosporins add to growing concern for multi-drug resistant NG. The high prevalence of PPNG and TRNG suggest strong selective pressure from background antibiotic use.
O3-S5.04 The post-trial effect of periodic presumptive treatment for vaginal infections on the incidence of bacterial vaginosis and Lactobacillus colonisation
Authors: Balkus J , Jaoko W , Mandaliya K , Richardson B , Masese L , Gitau R , Kiarie J , Marrazzo J , Farquhar C , McClelland R S 
Published: July 2011

BackgroundBacterial vaginosis(BV) is a highly prevalent infection that frequently recurs following standard treatment. In a randomised controlled trial (RCT) of oral periodic presumptive treatment (PPT) to reduce vaginal infections among Kenyan women, we observed a decrease in BV and an increase in Lactobacillus colonisation among women randomised to receive 2 g metronidazole +150 mg fluconazole monthly for 12 months. After the trial, women were invited to continue follow-up in an open cohort study. These post-trial data were analysed to test the hypothesis that the treatment effect would persist in the absence of PPT.MethodsData were obtained from women who completed all 12 RCT visits and attended ≥1 cohort study visit within 120 days of their final RCT visit. We used Andersen-Gill proportional hazards models to estimate the post-trial effect of the intervention vs placebo on the incidence of BV by Gram stain (Nugent score ≥7) and Lactobacillus species by culture on Rogosa agar.ResultsThe RCT enrolled 310 subjects (155 per arm), of whom 165 (83 active and 82 placebo) were included in this analysis. Included subjects were slightly older (median (IQR): 33 years (29–39) vs 30 years (26–35); p<0.001) and reported a longer duration of sex work (median (IQR): 6 years (2–11) vs 3 years (1–6); p<0.001) compared to those excluded. At the final RCT visit, which represented the baseline visit for this analysis, demographic and behavioural characteristics were similar by arm. The prevalence of BV at the final RCT visit was 16% in the active arm and 43% in the placebo arm (p<0.001). The post-trial incidence of BV was 260/100 person-years (p-yrs) in the active arm vs 358/100 p-yrs in the placebo arm (HR=0.76; 95% CI: 0.51% to 1.12%). The prevalence of Lactobacillus colonisation at the final RCT visit was 17% in the active arm and 18% in the placebo arm (p=0.81). The post-trial incidence of Lactobacillus colonisation was 180/100 p-yrs in the active arm vs 127/100 p-yrs in the placebo arm (HR=1.42; 95% CI: 0.85% to 2.71%).ConclusionsDespite a decrease in BV and an increase in Lactobacillus colonisation during the RCT, the effect of PPT was not sustained during the 120 days following cessation of the intervention. New interventions that reduce BV recurrence and promote long-term Lactobacillus colonisation without the need for ongoing PPT or suppressive therapy are needed.
O3-S6.01 Improved diagnostics of bacterial vaginosis with molecular techniques
Authors: Speksnijder A , Gruteke P , Jonker D , de Vries H , van Dam A 
Published: July 2011

BackgroundBacterial vaginosis(BV) is a disturbance of the vaginal microflora. BV can cause discharge complaints and lead to pelvic inflammatory disease, ectopic pregnancy and premature birth. We evaluated a combination of PCR assay's and whole bacterial community analysis with the standard diagnostic algorithm to validate a molecular assay for the determination of BV.Methods160 women with vaginal discharge complaints were included. 80 women were classified as BV and 80 as non-BV according to Amsel criteria. Gram stains from vaginal smears were made for Nugent scoring. Vaginal swabs were tested with PCR assays forGardnerella vaginalis,Atopobium vaginae, BV associated bacterium type 2 (BVAB2) and Megaspheara type 1 (MS1). Whole bacterial community analysis was performed by fluorescent Terminal Restriction Fragment Length polymorphism (TRFLP) of 16S-rDNA. TRFLP patterns and predictive fragments of a number of BV associated bacteria were analysed with Bionumerics software (Applied Maths, Belgium).ResultsCompared to Amsel criteria, the highest sensitivity of 100% was achieved with a duplex PCR for G. vaginalis and/orA vaginaeand the highest specificity of 86% was found with a singleplex BVAB2 specific PCR. Best overall performance was shown using a duplex real time PCR for BVAB2 and/or MS1 with a sensitivity of 90% and a specificity of 78% with respect to Amsel criteria. Using Nugent criteria as a standard, this duplex PCR has a sensitivity of 84% and specificity of 86%. From TRFLP results, the presence of predictive fragments ofPrevotella, Aerococcus, Megaspheara, Mycoplasma, Peptostreptococcus, Leptotrichia, Eggerthella, Gardnerella, AtopobiumandDialisterwas most associated with BV positive samples. Cluster analysis of microbial profiles revealed clear differences between BV and non-BV and indicated possible intermediate or transition stages.ConclusionsA combination of bacterial species are involved in BV. For molecular diagnostics a duplex PCR of Gardnerella en/of Atopobium can be used for initial screening confirmed by a BVAB2 specific PCR. A more effective alternative is a real time duplex PCR targeting BVAB2 and/or MS1. Microbial profiling supports most targets used in the PCR assays. Cluster analysis of microbial profiles can be used to interpret discordant validation results and possibly for diagnosis.
O3-S6.03 The diagnosis of lymphogranuloma venereum at one's fingertips
Authors: Crucitti T , Smet H 
Published: July 2011

BackgroundOutbreaks of Lymphogranuloma venereum (LGV) in sexual networks of men who have sex with men (MSM) are reported in several countries in Europe. Although accurate laboratory diagnosis is required to provide adequate patient management, the laboratory identification of LGV can be problematic.ObjectiveTo establish a fast and reliable testing algorithm for the identification ofChlamydia trachomatisL serovars.MethodsPreviously, anal specimens from MSM suspected to be positive forC trachomatiswere tested with a testing algorithm using commercial molecular amplification assays. ConfirmedC trachomatissamples were then analysed in batches by RFLP to identify the L serovars. From September 2010 onwards, the Abbott CT/NG Real Time PCR has been used for the detection ofC trachomatisin biological specimens collected at or referred to the ITM for Chlamydial infection diagnosis. Furthermore, confirmation ofC trachomatisand identification of the L serovar types are performed with an in-house Real Time PCR assay. This assay uses DNA extract obtained with the Abbott assay. The selection of the primers and test procedure is based on the publication by Chen et al. and includes two specific probes for the detection of the L and the non L serovars.ResultsOut of a total of 940 samples tested with the new methods, we detected 58 (6.2%) positive samples forC trachomatisand of those 12 (20.7%) were L serovars. Eight were detected in specimens collected from the anus, two in urethral specimens, one in urine, and one in a vaginal specimen. All non vaginal specimens were collected from men. With the Abbott CT/NG Real Time PCR for screening and the in house RT PCR assay for confirmation, we were able to confirm positive results forC trachomatisand to distinguish the L serovar from the non L serovar types within 2 days after specimen reception. In addition the in house RT PCR assay was more sensitive, more discriminative and at least 4 times cheaper compared to the RFLP method.ConclusionThe detection of L serovar ofC trachomatiscan be done on a routine basis at a very acceptable cost and test around time. The L serovar types may be more frequent in Belgium then initially thought, they are present in various biological specimens and possibly in women.Abstract O3-S6.03 Table 1LGVV TestingYearspecimens tested*L serovarnon L serovarnot typable2011 January19641102010 Sept-Dec74483502010 Jan-Aug231490200923175120081311†11200719135120061474320056213200411821*Until September 2010 only male anal specimens or rectal biopsies were tested except for 2008 when 2 specimens from penile ulcers were tested.†Two penile ulcer specimens.
O3-S6.06 Self-collection vs physician-collection for the detection ofChlamydia trachomatis,Neisseria gonorrhoeae,Trichomonas vaginalisandMycoplasma genitalium
Authors: Kwatampora J , Senkomago V , Mugo N , Hill C , Ting J , Chitwa M , Patel S , Gukare H , Kimani J , Smith J 
Published: July 2011

BackgroundTo determine the efficacy of self-collection for primary screening of an array of sexually transmitted infections.MethodsA cross-sectional baseline analysis was conducted on a cohort of 300 female sex workers (FSW) within an outpatient clinic from a suburban/slum area of Nairobi, from December 2009 to June 2010. APTIMA transcription-mediated amplification (TMA) assays (Gen-Probe Incorporated) were used for the detection ofChlamydia trachomatis(CT),Neisseria gonorrhoeae(GC),Trichomonas vaginalis(Trich) andMycoplasma genitalium(MGen) infections and, were analysed in San Diego, California. The APTIMA COMBO 2 assay (AC2) was used for CT/GC, the APTIMATrichomonas vaginalisassay for Trich, and an APTIMAMycoplasma genitaliumresearch assay for Mgen. FSW conducted a self-collected sample in privacy, based on standardised instructions, and then underwent a pelvic exam to obtain a physician-collected sample.ResultsA total of 299 FSW (mean age of 30) participated, of which 15% were HIV-seropositive. MGen was the most common infection (12.7% in physician; 20.7% in self-collection), followed by Trich (7.7%; 9.7%), CT (4.3%; 5.4%), and GC (2.7%; 3.3%). For all STIs examined, the self-collected samples detected more positive cases than the physician-collected samples. No self-collected sample missed an infection that was picked by the physician sample. κ for agreement between self-collected and physician-collected samples were high for CT: 0.89, GC: 0.89 and Trich: 0.87, and slightly lower for MGen: 0.73. Using physician sampling as the gold-standard, the sensitivity of self-collection was 100% for all STIs. The specificity for self-collection was high for CT, GC, and Trich (99.0%, 99.3% and 97.8% respectively) and slightly lower for MGen (91.6%).ConclusionA single self-collected sample appeared to perform with comparable sensitivity and specificity to that of physician-collected sampling for the detection ofChlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalisandMycoplasma genitalium.
O4-S1.02 Molecular cloning and expression of hydrogenosomal malate dehydrogenase ofTrichomonas vaginalis
Authors: Ardalan S , Lee C , Garber G 
Published: July 2011

BackgroundTrichomoniasis, a sexually transmitted disease caused byTrichomonas vaginalis, is associated with adverse pregnancy outcomes, and increased risk of HIV acquisition. Malate dehydrogenase (MDH), which catalyses the interconversion of malate to oxaloacetate, has a pivotal role in the survival and pathogenicity of this amitochondrial protozoan. The objective of this study was to clone and express Malate dehydrogenase gene ofT vaginalis, and analyse the biological function of this hydrogenosomal enzyme.MethodsThe MDH gene from a clinical isolate ofT vaginaliswas amplified by PCR, and cloned into pET101/D-TOPO vector with a C-terminal 6XHis tag. Positive clones were screened and identified by restriction endonuclease digestion and sequence analysis. The plasmid pET101/D-MDH was then transformed into E.coli BL21(DE3) to express after IPTG induction. The expression product further analysed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. The recombinant protein was purified with Ni-NTA agarose under native conditions. Western blot, using antibody raised against whole cellT vanginalis, was performed to determine the immunogenicity of purified recombinant protein.ResultsThe recombinant plasmid pET101/D-MDH was constructed successfully. High homology (98%) of nucleotide sequence was revealed between the cloned MDH and the corresponding gene. The recombinant protein showed a high expression level when induced with 1 mM IPTG at 37° C for 4 h. SDS-PAGE analysis showed that the recombinant MDH protein with the correct molecular weight (about 60 kDa) was expressed in E.coli BL21 (DE3). Western blotting revealed that the purified recombinant protein was specifically recognised by sera from mice infected with whole cellT vaginalis.ConclusionsA prokaryotic expression system ofT vaginalisMalate dehydrogenase gene has been established successfully. The immunogenicity of the recombinant protein has been tested. The present study shows that the recombinant MDH is specific and suitable for use as an antigen for detecting anti-Trichomonas vaginalisIgG antibodies. Our work has established a good foundation for future studies onT vaginalisvaccine construction.
O4-S1.03 Defining the in vitro functions of monoclonal antibodies developed to theHaemophilus ducreyitrimeric autotransporter DsrA
Authors: Leduc I 
Published: July 2011

BackgroundThe DsrA protein ofHaemophilus ducreyi, the etiological agent of the genital ulcer disease chancroid, is a multifunctional outer membrane trimeric autotransporter (TA) and a virulence factor. MostH ducreyistrains, which are grouped in two classes (I and II), express a DsrA protein. Although DsrA proteins from both classes ofH ducreyistrains share little identity in their N-terminal functional passenger domain, both are involved in serum resistance and function as adhesins to the extracellular matrix (ECM) proteins fibronectin (Fn) and vitronectin (Vn), as well as to fibrinogen (Fbg) and HaCat keratinocytes.MethodsMonoclonal antibodies (mAbs) to DsrA were developed by immunising mice with full-length recombinant DsrA from class I strain 35 000HP (DsrAI). Western blots were used to determine the specificity of the mAbs and their ability to recognise multimers of DsrA. Whole-cell binding ELISAs were used to examine the capacity of the mAbs to bind the surface ofH ducreyi. The domains and the shortest nominal peptides of DsrA recognised by those mAbs were identified using a library of truncated DsrA proteins expressed in a dsrA mutant, a peptide library representing full-length DsrAI, as well as Surface Plasmon Resonance and mutagenesis studies. mAbs were tested for bactericidal activity and their ability to block binding of Fn, Vn and Fbg byH ducreyiusing bactericidal assays and whole cell blocking assays, respectively.ResultsAnti-DsrAI mAbs bound monomers and dimers of the DsrA protein from several class IH ducreyistrains but not the DsrAII protein. mAb 1.82 bound native DsrAI protein at the surface of a panel of class IH ducreyiisolates, but not the H .ducreyi strains that cause cutaneous chancroid. The DsrA protein from these strains was recognised by mAb 4.79, along with the DsrA protein from strain 35 000HP. Both 1.82 and 4.79 bound with high affinity to peptides in the N-terminal region of the DsrA translocator domain and the shortest nominal epitope for 1.82 is MEQNTHNINKLS. In whole cell blocking assays, mAb 1.82 partially blocked binding of Fn and Fbg by class IH ducreyistrain 35 000HP.Conclusions1.82 and 4.79 are DsrAI-specific mAbs that recognise multimers of DsrA and bind the surface of intactH ducreyi. Both mAbs bind an epitope in the N-terminal region of the translocator domain of DsrAI with high affinity. mAb 1.82 has modest Fn and Fbg blocking activity.
O4-S1.04 Rapid spread of herpes simplex virus-2 in the human genital tract
Authors: Schiffer J , Swan D , Magaret A , Johnston C , Selke S , Wald A , Corey L 
Published: July 2011

BackgroundGenital herpes simplex virus-2 (HSV-2) infection consists of shedding episodes that correlate with transmission and genital lesion formation. Episodes are heterogeneous in terms of viral production and duration.MethodsUsing quantitative PCR data from 14 685 daily genital swabs performed daily in 531 persons, we summarised 1020 episodes according to their frequency, duration, peak HSV DNA copy number, first and last swab copy number, expansion and decay slopes, and morphology. We designed competing dynamical stochastic mathematical models and attempted to fully reproduce result ranges for each of these episode features. The models assumed the possibility of concurrent, spatially distinct plaques of viral infection and immunologic response.ResultsOur spatial model reproduced all kinetic features of the empirical shedding data. The model and parameter set that achieved best fit highlights three distinct mechanisms of viral spread. First, HSV-2 is constantly dispersed from neurons to epidermal cells throughout the genital tract at a rate of ∼100 HSV DNA copies/day. Approximately 75 times each year, a neuron-derived viral particle infects an epidermal cell, initiating an infectious plaque of epidermal cells and a detectable shedding episode. Second, within each plaque, cell-to-cell spread of HSV-2 particles occurs extremely rapidly between epidermal cells. One cell can produce 105 cell-associated HSV genomic copies/day, with 3% of viral particles infecting a neighbouring cell each day. In large plaques, >105 cells may be infected within ∼12 h producing up to 109 HSV DNA copies/ml. Third, cell-free viruses, despite being 3000-times less infectious than cell-associated viruses, decay more slowly and initiate spatially distinct secondary plaques. We use video simulations to display that episodes longer than 3 days, consist of dozens of concurrent viral plaques. Despite rapid cell-to-cell spread of HSV-2, infected cells are eliminated by localised CD8+ T-cells within 24 h of plaque initiation. Moreover, the extent of secondary plaque formation prior to episode termination is determined by spatial CD8+ T-cell density surrounding the site of infection.ConclusionsGenital HSV-2 utilises three kinetically distinct methods of spread to initiate and sustain prolonged shedding episodes. The extent and severity of secondary plaque formation is determined by spatial immune cell density.