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To evaluate the usefulness of different commercial enzyme linked immunosorbent assays (ELISAs) for the detection of IgM antibodies against Toxoplasma gondii the results of six of these assays for a panel of 81 sera were compared. The following tests were selected: Toxoplasma gondii IgM ELISA (Clark Laboratories), Toxoplasma IgM EIA (Labsystems), Toxo-M EIA (Abbott), Toxonostika M (Organon), Toxo M Enzyme Immunoassay (Hybritech) and Platelia Toxo IgM (Diagnostics Pasteur). An antibody capture ELISA developed at our laboratory was used as the reference test. An IgM immunoblotting assay was also performed. Four (Toxoplasma IgM EIA, Tox-M EIA, Toxonostika M, and Platelia Toxo IgM) of the commercial IgM ELISAs gave a high sensitivity and a high specificity. Toxo-M EIA, Toxonostika M, Toxoplasma IgM EIA and the Toxo M Enzyme Immunoassay were too insensitive, and the Toxoplasma gondii IgM ELISA was both insensitive and unspecific. No remarkable differences were observed between the results of indirect or antibody capture ELISAs, and between the results of ELISAs performed with polyclonal or monoclonal antibodies. [ABSTRACT FROM PUBLISHER]

The post-pericardiotomy syndrome (PPS) is a common complication of cardiac surgery. In order to better understand the pathogenesis of this complication we undertook a prospective, triple blind study of consecutive long term survivors of cardiac surgery. We followed 82 patients and determined anti-heart antibodies (AHA), circulating immune complexes (CIC) and anti-viral antibodies (AVA) on sera pre-operatively and serially post-operatively. According to the clinical features of pericarditis, fever and leucocytosis, patients were divided into three groups: (I) complete PPS with all three symptoms, (2) incomplete PPS with two symptoms and (3) no PPS with one or no symptoms. Clinical PPS was found in 16 patients (19.6%). All of these patients had positive AHA, 12 patients (75%) had increased CIC and five patients (31 %) had a four-fold or greater rise in titre to viruses studied. Twenty-four patients (29.2%) had an incomplete PPS. It was accompanied by positive AHA in 17 patients (70.8%), increased CIC in 14 patients (58.3%) and a four-fold rise or greater in virus titre in seven patients (29.2%). No PPS was found in forty-two patients (51.2%). It was accompanied by positive AHA in eight patients (19%), increased CIC in 10 patients (24%) and a four-fold or greater rise in virus titre in 12 patients (28.6%). There was a good correlation between the presence of PPS, AHA, CIC and the type of operation. Heart valve replacement surgery was more frequently complicated by PPS. Development of post-operative AHA and increased CIC were also more frequently found. We found a good correlation between PPS, positive AHA and increased CIC. No correlation was found between PPS and virus serology. [ABSTRACT FROM AUTHOR]

Objectives: To determine the prevalence of high risk human papillomavirus (HPV) types in Nicaraguan women with histological proved pre-neoplastic and neoplastic cervical lesions, and to assess its potential impact on preventive strategies. Methods: 206 women with histopathological confirmed cervical lesions (CIN I or worse) were screened for HPV DNA on a liquid based cytology sample, using an HPV short fragment polymerase chain reaction based assay. HPV positive samples were genotyped with a reverse hybridisation line probe assay (Lipa). HPV negative samples were re- analysed using type specific real time polymerase chain reaction. Results: Of all lesions CIN II or worse, 12% tested negative. Prevalence of high risk HPV increased from 48.1% in cervical intraepithelial neoplasia I (CIN I) to 94.7% in invasive squamous cervical carcinoma (SCC). The most prevalent high risk HPV types were, in order of prevalence rate, HPV 16, 58, 31 and 52. HPV 16 and/or HPV 31 were present in 63.2% of 5CC cases. Conclusion: Targeting HPV 16 and 31 with prophylactic vaccines could possibly have an important impact on the incidence of invasive cervical carcinoma in Nicaragua. Further research is needed to define the oncogenic potential of other high prevalent HPV genotypes. Meanwhile, primary prevention and cervical cancer screening programmes should be optimised. [ABSTRACT FROM AUTHOR]

Background: increased levels of systemic inflammatory markers appear to be related to coronary heart disease (CHD) both in asymptomatic individuals and in subjects with established CHD. Whether these associations are related to confounding coronary risk factors or are explicable through chronic infectious conditions is not clear. Objectives: (1) to determine whether subjects with stable CHD differ from normal controls in inflammatory markers (CRP, SAA and fibrinogen) and/or in serostatus of four infectious agents (Helicobacter pylori, Chlamydia pneumoniae, CMV and EBV), independent of classical coronary risk factors. (2) To determine whether these inflammatory markers are related to the serostatus against these four infectious agents either in patients with CHD or in normal subjects. Methods: in a large epidemiologic survey, 446 out of 16 307 men at work, aged 35–59 years, had antecedents of myocardial infarction, CABG or PTCA or had prominent Q/QS waves on their resting ECG. They were compared with double the number (n=892) of men, matched for age, educational level and industry. Inflammatory biomarkers (CRP, fibrinogen and SAA) and antibodies against H. pylori, C. pneumoniae, CMV and EBV were measured, besides classical coronary risk factors. Results: in univariate analyses, cases had higher CRP, fibrinogen and SAA levels than controls, but no differences were observed in serumantibody levels to any of the infectious agents. Markers of previous infections were not related to inflammatory biomarkers. In multivariate analyses CRP was significantly different between cases and controls independent of differences in other coronary risk factors and in the use of lipid lowering drugs and antiplatelet aggregants. Conclusion: in men at work with CHD, CRP levels are significantly different from controls, independent of known risk factors. No association was found between inflammatory biomarkers and positive serostatus against four infectious agents, neither in the patients nor in the healthy controls. [Copyright &y& Elsevier]

Glucolipids (GLs) are glycolipid biosurfactants with promising properties. These GLs are composed of glucose attached to a hydroxy fatty acid through a ω and/or ω-1 glycosidic linkage. Up until today these interesting molecules could only be produced using an engineered Starmerella bombicola strain (∆ugtB1::URA3 G9) producing GLs instead of sophorolipids, albeit with a very low average productivity (0.01 g·L -1 ·h -1 ). In this study, we investigated the reason(s) for this via reverse-transcription quantitative polymerase chain reaction and Liquid chromatography-multireaction monitoring-mass spectrometry. We found that all glycolipid biosynthetic genes and enzymes were downregulated in the ∆ugtB1 G9 strain in comparison to the wild type. The underlying reason for this downregulation was further investigated by performing quantitative metabolome comparison of the ∆ugtB1 G9 strain with the wild type and two other engineered strains also tinkered in their glycolipid biosynthetic gene cluster. This analysis revealed a clear distortion of the entire metabolism of the ∆ugtB1 G9 strain compared to all the other strains. Because the parental strain of the former was a spontaneous ∆ura3 mutant potentially containing other "hidden" mutations, a new GL production strain was generated based on a rationally engineered ∆ura3 mutant (PT36). Indeed, a 50-fold GL productivity increase (0.51 g·L -1 ·h -1 ) was obtained with the new ∆ugtB1::URA3 PT36 strain compared with the G9-based strain (0.01 g·L -1 ·h -1 ) in a 10 L bioreactor experiment, yielding 118 g/L GLs instead of 8.39 g/L. Purification was investigated and basic properties of the purified GLs were determined. This study forms the base for further development and optimization of S. bombicola as a production platform strain for (new) biochemicals., (© 2019 Wiley Periodicals, Inc.)

Both strain engineering and process optimization are intensively studied in microbial biosurfactant literature. However, screening of multiple strains and/or medium components in parallel is a very labor-intensive and timely process, considering the only applied technique nowadays is evaluation through shake flask and/or bioreactor experiments. Therefore, in this work, the development, optimization, and application of a more throughput technique-based on 24-deep well plates-are described for a new Starmerella bombicola strain producing bolaform sophorolipids. To develop an optimal setup, the influence of plate position and culture volume and the type of sandwich cover was investigated. Optimal parameters, which did not result in significant differences compared with shake flask experiments concerning growth, glucose consumption, and production of novel sophorolipids, were defined and validated. Next, the new method was applied to evaluate the influence of the use of alternative (commercial) nitrogen sources in comparison with the yeast extract currently applied in the production medium, aiming to increase production efficiency. Self-made yeast extracts from S. bombicola cells were also included to evaluate possible recycling of cells after fermentation. In conclusion, the designed method enabled the efficient and successful comparison of ten different nitrogen sources in varying concentrations (1, 4, and 10 g/L) on bola sophorolipid production, which can now also be performed for other parameters important for growth and/or glycolipid production.

A bio-based glycolipid bolaamphiphile (glyco-bolaamphiphile) has recently been produced (Van Renterghem et al., Biotechnol. Bioeng., 2018, 115, 1195-1206) on a gram scale by using the genetically-engineered S. bombicola strain Δat Δsble Δfao1. The glyco-bolaamphiphile bears two symmetrical sophorose headgroups at the extremities of a C16:0 (ω-1 hydroxylated palmitic alcohol) spacer. Its atypical structure has been obtained by redesigning the S. bombicola strain Δat Δsble, producing non-symmetrical glyco-bolaamphiphile, with an additional knock out (Δfao1) and feeding this new strain with fatty alcohols. The molecular structure of the glyco-bolaamphiphile is obtained by feeding the new strain a saturated C16 substrate (palmitic alcohol), which enables the biosynthesis of bolaform glycolipids. In this work, we show that the bio-based glyco-bolaamphiphile readily forms a hydrogel in water at room temperature, and that the hydrogel formation depends on the formation of self-assembled fibers. Above 28 °C, the molecules undergo a gel-to-sol transition, which is due to a fiber-to-micelle phase change. We provide a quantitative description of the Self-Assembled Fibrillar Network (SAFiN) hydrogel formed by the glyco-bolaampiphile. We identify the sol-gel transition temperature, the gelling time, and the minimal gel concentration; additionally, we explore the fibrillation mechanism as a function of time and temperature and determine the activation energy of the micelle-to-fiber phase transition. These parameters allow control of the elastic properties of the glyco-bolaamphiphile hydrogel: at 3 wt% and 25 °C, the elastic modulus G' is above the kPa range, while at 5 °C, G' can be tuned between 100 Pa and 20 kPa, by controlling the undercooling protocol.

Glycolipid microbial biosurfactants, such as sophorolipids (SLs), generate high industrial interest as 100% biobased alternatives for traditional surfactants. A well-known success story is the efficient SL producer Starmerella bombicola, which reaches titers well above 200 g/L. Recent engineering attempts have enabled the production of completely new types of molecules by S. bombicola, e.g. the bolaform SLs. Scale-up of bolaform SL production was performed at 150 L scale. The purified product was evaluated in detergent applications, as classic SLs are mostly applied in eco-friendly detergents. In this paper, we show that they can be used as green and non-irritant surfactants in for example (automatic) dishwashing applications. However, due to the presence of an ester function in the biosurfactant molecule a limited chemical stability at higher pH values (>6.5) was noticed, (therefore called 'non-symmetrical' (nsBola)) which, is a major drawback that will most likely inhibit market introduction. An integrated bioprocess design (IBPD) strategy was thus applied to resolve this issue. The strategy was to replace the fed fatty acids with fatty alcohols, to generate so-called "symmetrical bolaform (sBola) sophorosides (SSs)," containing two instead of one glycosidic bond. Next to a change in feeding strategy, the blocking of the fatty alcohols from metabolizing/oxidizing through the suggested ω-oxidation pathway was necessary. For the latter, two putative fatty alcohol oxidase genes (fao1 and fao2) were identified in the S. bombicola genome and deleted in the bolaform SL producing strain (ΔatΔsble). Shake flask experiments for these new strains (ΔatΔsbleΔfao1 and ΔatΔsbleΔfao2) were performed to evaluate if the fed fatty alcohols were directly implemented into the SL biosynthesis pathway. Indeed, sBola sophorosides (SSs) production up to 20 g/L was observed for the ΔatΔsbleΔfao1 strain. Unexpectedly, the ΔatΔsbleΔfao2 strain only produced minor amounts of sBola sophorosides (SSs), and mainly nsBola SLs (alike the parental ΔatΔsble strain). The sBola sophorosides (SSs) were purified and their symmetrical structure was confirmed by NMR. They were found to be significantly more stable at higher pH, opening up the application potential of the biosurfactant by enhancing its stability properties., (© 2018 Wiley Periodicals, Inc.)

Application of Bethesda guidelines on cervical cytology involves human papillomavirus (HPV) determinations on all ASC-US and ASC-H results. We compared HPV DNA results in view of the eventual development of a cervical intraepithelial neoplasia lesion determined either on cytology or histology. A total of 214 liquid-based cytology samples were analysed. Three different HPV DNA methods were applied: the Abbott RealTime High Risk HPV test, INNO-Lipa HPV Genotyping Extra and Full Spectrum PCR HPV Amplification and Detection/Genotyping System by Lab2Lab Diagnostic Service. A comparison of these three methods showed full concordance only for 49 samples (23%), and 27 (13%) of the samples were discordant in indicating the presence of the high-risk HPV type. Out of 214 patients, 88 were selected who presented with a cervical intraepithelial neoplasia or a VAIN lesion at follow-up cytology or histology. In this group, full concordance with HPV genotyping was present only in 19 (22%) follow-up samples. Nine (10%) follow-up samples showed discordant results for the presence of a high-risk genotype between the three genotyping methods tested either by negativity for high-risk HPV by one of the methods (n=6) or by failure to genotype HPV (n=2), or by a combination of both (n=1). Moreover, discordance for the detection of HPV16 or HPV18 was observed between the three HPV DNA genotyping methods used in 9 (10%) follow-up samples. In addition, the performance of genotyping methods on 20 external quality samples was assessed, showing discordant results for HPV16 and HPV18. Major differences were found in the genotyping results according to the HPV DNA method. Our findings highlight the importance of careful interpretation of data from studies using different HPV genotyping methods and underline the need for standardization by method validation in clinical laboratories, especially in the setting of primary HPV screening.

Objective: Human papillomaviruses (HPV) are classified according to their potential for the development of cervical neoplasia. However, the carcinogenicity of HPV types forms an evolving continuum based on the newly available data especially regarding the role of probable and possible high-risk HPV types (pHR-HPV). The objective of the present work was to evaluate clinical significance of the pHR-HPV53., Study Design: An observational cohort study of potential aetiological association between infection with HPV53 and development of high-grade cervical cytology was performed. The study was conducted in two geographically remoted hospitals, in Belgium and Democratic Republic of Congo, as an attempt to collect data from regions with different geographical distribution of HPV genotypes. The samples were taken during routine gynaecological visit in outpatient clinics of both participating hospitals., Results: A total of 2283 liquid-Pap samples were taken from 1465 women at Ghent University Hospital, Belgium, and from 660 women at General Hospital and Ngaliema Hospital of Kinshasa, DRC. "HPV53-only"-pattern as evaluated by full HPV genotyping was found in samples from only 34 (1.6%) samples. The initial cytology represented next to non-dysplastic, undetermined and low-grade lesions also high-grade lesions (12%). For 26 (76.5%) from the 34 women presented with "HPV53-only"-pattern follow-up results were available showing no progression to malignancy., Conclusion: Our findings support very low to lacking carcinogenic potential of HPV53. Recognising extreme rarity in cervical cancer next to high prevalence in general population of HPV53, further studies investigating progression to high-grade lesions are needed to elucidate the oncogenic potential of pHR-HPV53., (Copyright © 2015. Published by Elsevier Ireland Ltd.)

The objective of the study was to evaluate prospectively the added value of E6/E7 mRNA detection in a stepwise protocol. A total of 1,422 samples were collected over a period of 17 months. The samples were referred for human papillomavirus (HPV) genotyping if they showed cytological evidence of atypical squamous cells of undetermined significance, low- or high-grade squamous intraepithelial lesion. If one or more of HPV types 16, 18, 31, 33, or 45 were present, mRNA was analyzed by the NucliSENS EasyQ HPV assay. The genotypical distribution of high-risk HPV was very heterogeneous; HPV 16, 18, 31, 33, and 45 represented 20.2%, 3.4%, 10.8%, 3.4%, and 3.8% of HPV-positive samples, respectively. Follow-up data were available for 35 patients. Although over the half (51.4%) of follow-up samples showing HPV DNA/mRNA consensus evolved to cervical intraepithelial neoplastic lesions, 25.7% showed no progression to neoplasia despite mRNA positivity. However, the major concern was the group (14.3%) that showed progression to cervical intraepithelial neoplasia despite mRNA negativity: all but one of these cases had a high-risk HPV genotype other than the five included in the NucliSENS EasyQ HPV assay. Markedly, 66.7% of the discordant samples between colposcopy and histology that underestimated the degree of cervical dysplasia were found in this group. Close monitoring of high-risk HPV DNA-positive/mRNA-negative cases remains necessary, which leads to questions about the added value of the evaluated protocol., (Copyright © 2013 Wiley Periodicals, Inc.)

Introduction: Chlamydia antibody testing (CAT) in serum has been introduced as a screening method in the infertility workup. We evaluated the test characteristics of two ELISA tests compared to micro-immunofluorescence tests (MIFs). MIFs are considered the gold standard in the C. trachomatis IgG antibodies detection. We also compared the accuracy of all CAT tests in predicting tubal subfertility, using laparoscopy as a reference., Methodology: Four commercial serological methods were used to analyse 101 serum samples for the presence of C. trachomatis IgG antibodies from patients at the Infertility Clinic of Ghent University Hospital. The diagnostic utility for prediction of tubal infertility of serological methods was evaluated based on patients' medical records., Results: A comparison of the serological assays showed  little difference  in the major performance characteristics: the sensitivities of all MIFs and ELISAs were 100% for all assays (except the ELISA Vircell, with a sensitivity of 90%), and the specificities ranged from 92% for MIF Ani Labsystems to 98% for the MIF Focus and ELISA Vircell. As compared to laparoscopy data, CAT positivity in subfertile women with tubal damage (n=40) did not significantly differ from that of subfertile women without tubal damage (n=61): Positive predictive values (PPV) of CAT ranged from 53% to 60% and negative predictive values (NPV) ranged from 62% to 64%. , Conclusion: evaluated ELISAs are comparable to MIFs in the detection of C. trachomatis IgG antibodies and should be preferred for large serological studies, especially in resource poor settings.