bluuebunny/crossref_metadata_2025_split huggingface dataset:
Submicroscopic malaria infections in pregnant women from six departments in Haiti
Authors: Elbadry Maha A. , Tagliamonte Massimiliano S. , Raccurt Christian P. , Lemoine Jean F. , Existe Alexandre , Boncy Jacques , Weppelmann Thomas A. , Dame John B. , Okech Bernard A. 
Published: June 2017

AbstractObjectivesTo describe the epidemiology of malaria in pregnancy in Haiti.MethodsCross‐sectional study among pregnant women in six departments of Haiti. After obtaining informed consent, whole blood samples and demographic surveys were collected to investigate malaria prevalence, anaemia and socio‐behavioural risk factors for infection, respectively. A total of 311 pregnant women were screened for Plasmodium falciparum infection using a rapid diagnostic test (RDT), microscopy and a novel, quantitative reverse transcriptase polymerase chain reaction method (qRT‐PCR).ResultsOverall, 1.2% (4/311) of pregnant women were tested positive for malaria infection by both microscopy and RDT. However, using the qRT‐PCR, 16.4% (51/311) of pregnant women were positive. The prevalence of malaria infection varied with geographical locations ranging between 0% and 46.4%. Additionally, 53% of pregnant women had some form of anaemia; however, no significant association was found between anaemia and submicroscopic malaria infection. The socio‐behavioural risk factors identified to be protective of malaria infection were marital status (P < 0.05) and travel within one month prior to screening (P < 0.05).ConclusionThis study is the first to document the high prevalence of submicroscopic malaria infections among pregnant women in Haiti and identify social and behavioural risk factors for disease transmission.
How sukuk shapes firm performance
Authors: Klein Paul‐Olivier , Weill Laurent , Godlewski Christophe J. 
Published: June 2017

AbstractWith the large expansion of Islamic finance in the recent years, sukuk, which are the Sharia‐compliant substitute to conventional bonds, are now becoming more prominent. The aim of this study was to examine the impact of sukuk issuance on firm performance. To do so, we analyse how stock market performance and operating performance (OP) are influenced by issuance of sukuk and bonds on a sample of Malaysian listed companies. We consider the short‐term and medium‐term stock market reaction through the computation of cumulative abnormal returns and buy‐and‐hold abnormal returns. We investigate the impact on OP by performing regressions and by calculating abnormal operating performance (AOP) so that we can compare how issuance affects similar firms. We find that sukuk issuance generates a negative stock market reaction both in the short term and in the medium term. We also find evidence that issuing sukuk hampers OP. The analysis of AOP shows that sukuk issuers have better performance than their matched bond issuers, but that sukuk contributes to reduce the gap in performance over time. Overall, our results support the view that sukuk issuance hampers stock market performance, but that it is not attributable to a signalling effect on the bad financial situation of the issuer. We interpret our findings as evidence of adverse selection taking place on the financed projects and agency problems stemming from the specific sukuk structuring with stock market investors more reluctant to invest in sukuk issuers.
Efficacy of Paromomycin-Chloroquine Combination Therapy in Experimental Cutaneous Leishmaniasis
Authors: Wijnant Gert-Jan , Van Bocxlaer Katrien , Yardley Vanessa , Murdan Sudaxshina , Croft Simon L. 
Published: June 2017

ABSTRACT

The 4-aminoquinoline chloroquine (CQ) is clinically used in combination with doxycycline to cure chronic Q fever, as it enhances the activity of the antibiotic against the causative bacterium
Coxiella burnetii
residing within macrophage phagolysosomes. As there is a similar cellular host-pathogen biology for
Leishmania
parasites, this study aimed to determine whether such an approach could also be the basis for a new, improved treatment for cutaneous leishmaniasis (CL). We have evaluated the
in vitro
and
in vivo
activities of combinations of CQ with the standard drugs paromomycin (PM), miltefosine, and amphotericin B against
Leishmania major
and
Leishmania mexicana
. In 72-h intracellular antileishmanial assays, outcomes were variable for different drugs. Significantly, the addition of 10 μM CQ to PM reduced 50% effective concentrations (EC
50
s) by over 5-fold against
L. major
and against normally insensitive
L. mexicana
parasites. In murine models of
L. major
and
L. mexicana
CL, daily coadministration of 50 mg/kg of body weight PM and 25 mg/kg CQ for 10 days resulted in a significant reduction in lesion size but not in parasite load compared to those for mice given the same doses of PM alone. Overall, our data indicate that PM-CQ combination therapy is unlikely to be a potential candidate for further preclinical development.
Nitrogen Source Stabilization of Quorum Sensing in the Pseudomonas aeruginosa Bioaugmentation Strain SD-1
Authors: Wang Mei-Zhen , Lai Bai-Min , Dandekar Ajai A. , Yang Yu-Sheng , Li Na , Yin Jun , Shen Dong-Sheng 
Published: June 2017

ABSTRACT

Pseudomonas aeruginosa
SD-1 is efficient at degrading aromatic compounds and can therefore contribute to the bioremediation of wastewater.
P. aeruginosa
uses quorum sensing (QS) to regulate the production of numerous secreted “public goods.” In wastewater bioaugmentation applications, there are myriad nitrogen sources, and we queried whether various nitrogen sources impact the stabilities of both QS and the bacterial populations. In a laboratory strain of
P. aeruginosa
, PAO1, the absence of a nitrogen source has been shown to destabilize these populations through the emergence of QS mutant “cheaters.” We tested the ability of SD-1 to grow in casein broth, a condition that requires QS for growth, when the nitrogen source with either NH
4
Cl, NaNO
3
, or NaNO
2
or with no added nitrogen source. There was great variability in susceptibility to invasion by QS mutant cheaters and, by extension, the stability of the SD-1 population. When grown with NH
4
Cl as an extra nitrogen source, no population collapse was observed; by contrast, two-thirds of cultures grown in the presence of NaNO
2
collapsed. In the populations that collapsed, the frequency of social cheaters exceeded 40%. NaNO
3
and NaNO
2
directly favor QS mutants of
P. aeruginosa
SD-1. Although the mechanism by which these nitrogen sources act is not clear, these data indicate that the metabolism of nitrogen can affect the stability of bacterial populations, an important observation for continuing industrial applications with this species.

IMPORTANCE
Bioaugmentation as a method to help remediate wastewater pollutant streams holds significant potential to enhance traditional methods of treatment. Addition of microbes that can catabolize organic pollutants can be an effective method to remove several toxic compounds. Such bioaugmented strains of bacteria have been shown to be susceptible to competition from the microbiota that are present in wastewater streams, limiting their potential effectiveness. Here, we show that bioaugmentation strains of bacteria might also be susceptible to invasion by social cheaters and that the nitrogen sources available in the wastewater might influence the ability of cheaters to overtake the bioaugmentation strains. Our results imply that control over the nitrogen sources in a wastewater stream or selective addition of certain nitrogen sources could help stabilize bioaugmentation strains of bacteria.
Laboratory Evolution of a Biotin-Requiring Saccharomyces cerevisiae Strain for Full Biotin Prototrophy and Identification of Causal Mutations
Authors: Bracher Jasmine M. , de Hulster Erik , Koster Charlotte C. , van den Broek Marcel , Daran Jean-Marc G. , van Maris Antonius J. A. , Pronk Jack T. 
Published: June 2017

ABSTRACT

Biotin prototrophy is a rare, incompletely understood, and industrially relevant characteristic of
Saccharomyces cerevisiae
strains. The genome of the haploid laboratory strain CEN.PK113-7D contains a full complement of biotin biosynthesis genes, but its growth in biotin-free synthetic medium is extremely slow (specific growth rate [μ] ≈ 0.01 h
−1
). Four independent evolution experiments in repeated batch cultures and accelerostats yielded strains whose growth rates (μ ≤ 0.36 h
−1
) in biotin-free and biotin-supplemented media were similar. Whole-genome resequencing of these evolved strains revealed up to 40-fold amplification of
BIO1
, which encodes pimeloyl-coenzyme A (CoA) synthetase. The additional copies of
BIO1
were found on different chromosomes, and its amplification coincided with substantial chromosomal rearrangements. A key role of this gene amplification was confirmed by overexpression of
BIO1
in strain CEN.PK113-7D, which enabled growth in biotin-free medium (μ = 0.15 h
−1
). Mutations in the membrane transporter genes
TPO1
and/or
PDR12
were found in several of the evolved strains. Deletion of
TPO1
and
PDR12
in a
BIO1
-overexpressing strain increased its specific growth rate to 0.25 h
−1
. The effects of null mutations in these genes, which have not been previously associated with biotin metabolism, were nonadditive. This study demonstrates that
S. cerevisiae
strains that carry the basic genetic information for biotin synthesis can be evolved for full biotin prototrophy and identifies new targets for engineering biotin prototrophy into laboratory and industrial strains of this yeast.

IMPORTANCE
Although biotin (vitamin H) plays essential roles in all organisms, not all organisms can synthesize this vitamin. Many strains of baker's yeast, an important microorganism in industrial biotechnology, contain at least some of the genes required for biotin synthesis. However, most of these strains cannot synthesize biotin at all or do so at rates that are insufficient to sustain fast growth and product formation. Consequently, this expensive vitamin is routinely added to baker's yeast cultures. In this study, laboratory evolution in biotin-free growth medium yielded new strains that grew as fast in the absence of biotin as in its presence. By analyzing the DNA sequences of evolved biotin-independent strains, mutations were identified that contributed to this ability. This work demonstrates full biotin independence of an industrially relevant yeast and identifies mutations whose introduction into other yeast strains may reduce or eliminate their biotin requirements.
The Two-Component Signal Transduction System VxrAB Positively Regulates Vibrio cholerae Biofilm Formation
Authors: Teschler Jennifer K. , Cheng Andrew T. , Yildiz Fitnat H. 
Published: June 2017

ABSTRACT

Two-component signal transduction systems (TCSs), typically composed of a sensor histidine kinase (HK) and a response regulator (RR), are the primary mechanism by which pathogenic bacteria sense and respond to extracellular signals. The pathogenic bacterium
Vibrio cholerae
is no exception and harbors 52 RR genes. Using in-frame deletion mutants of each RR gene, we performed a systematic analysis of their role in
V. cholerae
biofilm formation. We determined that 7 RRs impacted the expression of an essential biofilm gene and found that the recently characterized RR, VxrB, regulates the expression of key structural and regulatory biofilm genes in
V. cholerae
.
vxrB
is part of a 5-gene operon, which contains the cognate HK
vxrA
and three genes of unknown function. Strains carrying Δ
vxrA
and Δ
vxrB
mutations are deficient in biofilm formation, while the Δ
vxrC
mutation enhances biofilm formation. The overexpression of VxrB led to a decrease in motility. We also observed a small but reproducible effect of the absence of VxrB on the levels of cyclic di-GMP (c-di-GMP). Our work reveals a new function for the Vxr TCS as a regulator of biofilm formation and suggests that this regulation may act through key biofilm regulators and the modulation of cellular c-di-GMP levels.

IMPORTANCE
Biofilms play an important role in the
Vibrio cholerae
life cycle, providing protection from environmental stresses and contributing to the transmission of
V. cholerae
to the human host.
V. cholerae
can utilize two-component systems (TCS), composed of a histidine kinase (HK) and a response regulator (RR), to regulate biofilm formation in response to external cues. We performed a systematic analysis of
V. cholerae
RRs and identified a new regulator of biofilm formation, VxrB. We demonstrated that the VxrAB TCS is essential for robust biofilm formation and that this system may regulate biofilm formation via its regulation of key biofilm regulators and cyclic di-GMP levels. This research furthers our understanding of the role that TCSs play in the regulation of
V. cholerae
biofilm formation.
Features of optical coherence tomography predictive of choroidal neovascularisation treatment response in pathological myopia in association with fluorescein angiography
Authors: Lee Dong Hyun , Kang Hyun Goo , Lee Sung Chul , Kim Min 
Published: June 2017

Background/AimsThe aim of this study was to evaluate the usefulness of several optical coherence tomography (OCT) findings to estimate choroidal neovascularisation (CNV) activity in pathological myopia using fluorescein angiography (FA) as a reference.MethodsThis was a single-centre, retrospective study. The medical records of patients with active myopic CNV who received intravitreal bevacizumab treatment were reviewed. Parameters to monitor CNV activity were morphological features of CNV on OCT, such as CNV height, central foveal thickness, intraretinal cysts, subretinal fluid, fuzziness of the CNV border, CNV network area on FA, and haemorrhage or exudation on fundus photo.ResultsThere were 46 patients with active CNV enrolled in this study. After intravitreal bevacizumab treatment, all the previously mentioned parameters of CNV were significantly improved. Using logistic regression analyses with backward elimination, the fuzzy border seen on OCT showed the most significant correlation with improvement of leakage on FA, when compared with other variables such as intraretinal cysts, subretinal fluid or central foveal thickness (R2=0.324, p=0.009).ConclusionOur study showed that the fuzziness of the hyper-reflective CNV margin showed the most significant improvement and the strongest correlation with the improvement of CNV leakage on FA after intravitreal bevacizumab injections, suggesting its important role as an OCT parameter for the assessment of myopic CNV activity.
Use of Ruthenium-106 Brachytherapy for Iris Melanoma: The Scottish Experience
Authors: Agraval Umiya , Sobti Manvi , Russell Heather C , Lockington David , Ritchie Diana , Cauchi Paul , Kemp Ewan G , Chadha Vikas 
Published: June 2017

PurposeTo analyse long-term outcomes of ruthenium-106 (106Ru) plaque brachytherapy for the treatment of iris melanoma.MethodsWe retrospectively reviewed medical records of 19 consecutive patients with pure iris melanoma treated with 106Ru plaque brachytherapy between 1998 and 2016 at the Scottish Ophthalmic Oncology Service, Glasgow. The iris melanoma was treated with a ruthenium plaque placed on the corneal surface to deliver a surface dose of 555 Gy. We analysed vision preservation, local tumour control, radiation-related complications, eye retention rates, symptomatic metastasis and melanoma-related mortality.ResultsThe mean largest basal diameter of the lesions was 3.50±1.42 mm (range 1.6–6.5 mm), and the mean maximum height was 1.47±0.65 mm (range 0.7–2.8 mm). The tumour control and eye retention were 100% at a mean follow-up of 62 months (range 6–195 months). A 62% reduction in tumour height was observed on ultrasonography. Complications included cataract (68%), dry eye (47%), uveitis (37%) and scleral thinning (5%). At the final follow-up visit, the mean loss of Snellen visual acuity was 1.11±2.90 lines and vision of 6/9 or better was maintained in 53% of patients. None of the patients had evidence of symptomatic metastasis (non-imaged) or melanoma-related mortality.Conclusions106Ru plaque treatment for iris melanoma was highly effective a high tumour control, no tumour recurrences and a relatively a low complication rate.
Second primary malignancies in retinoblastoma patients treated with intra-arterial chemotherapy: the first 10 years
Authors: Habib Larissa A , Francis Jasmine H , Fabius Armida WM , Gobin Pierre Y , Dunkel Ira J , Abramson David H 
Published: June 2017

Background/AimsSurvivors of retinoblastoma carry a lifetime risk of secondary malignancies. It is well established that external beam radiation increases this risk; however, the risk with ophthalmic artery chemosurgery (OAC) remains unknown. We report on 10 years of experience with OAC and the rate of second primary malignancy (SPM) development.MethodsThis is a single-centre retrospective review approved by the Memorial Sloan Kettering Cancer Center Institutional Review Board of all patients who received OAC over a 10-year period, from May 2006 to November 2016. The second tumour incidence and survival in patients with germline disease (bilateral and unilateral with family history or confirmed germline mutation) was estimated using the Kaplan-Meier method. Patients who received external beam radiotherapy were excluded from analyses.ResultsTwo hundred and thirty-three patients with heritable retinoblastoma who received OAC were analysed. Nineteen patients were excluded for having received external beam radiation. The Kaplan-Meier estimate of the likelihood for SPM development was 2.7% at 5 years (95% CI 0 to 25). All of the SPMs were pineoblastomas and all patients had bilateral disease in this cohort.ConclusionsIn our 10-year experience, we have found that SPM development in patients with germline retinoblastoma treated with OAC alone is comparable to previously published rates. In the first 10 years, OAC did not increase the known incidence of SPMs. This cohort will continue to be followed to establish the rate of development with extended follow-up.
Optimal timing for elective caesarean delivery in a Chinese population: a large hospital-based retrospective cohort study in Shanghai
Authors: HU Yong , Shen Hong , Landon Mark B , Cheng Weiwei , Liu Xiaohua 
Published: June 2017

ObjectiveTo assess the relationship between the timing of antepartum elective caesarean delivery (CD) at term and perinatal outcomes in a Chinese population.MethodsWe conducted a retrospective cohort study of mode of delivery at a large obstetric centre in Shanghai, China between 2007 and 2014. Eligibility criteria included: term nulliparous women with a singleton gestation undergoing antepartum elective CD.ResultsThere were 19 939 women delivered by antepartum CD without indications, with 5.9% performed at 37–37 6/7 weeks, 36.2% at 38–38 6/7 weeks, 38.4% at 39–39 6/7 weeks, 15.4% at 40–40 6/7 weeks, 4.0% at ≥41 weeks. As compared with births at 39–39 6/7 weeks, births at 37 weeks were associated with an increased odds of neonatal respiratory disease (adjusted odds ratian(aOR): 4.82; 95% CI 3.35 to 6.94), neonatal infection (aOR: 3.68; 95% CI 1.80 to 7.52), hypoglycaemia (aOR: 3.85; 95%CI 2.29 to 6.48), hyperbilirubinaemia (aOR: 3.50; 95%CI 2.12 to 5.68), neonatal intensive care admission (aOR: 3.73; 95% CI 2.84 to 4.89) and prolonged hospitalisation (aOR: 7.51; 95% CI 5.10 to 11.07). Births at 38 weeks, 40 weeks or ≥41 weeks were also associated with an increased odds of neonatal respiratory disease with corresponding aORs (95% CI) of 2.26 (1.71 to 3.00), 1.97 (1.33 to 2.94) and 2.91 (1.80 to 4.70), respectively.ConclusionFor women undergoing elective CD, neonatal outcome data suggest that delivery at 39–39 6/7 complete weeks is optimal timing in a Chinese population.
Assessing the diagnostic accuracy of PCR-based detection ofStreptococcus pneumoniaefrom nasopharyngeal swabs collected for viral studies in Canadian adults hospitalised with community-acquired pneumonia: a Serious Outcomes Surveillance (SOS) Network of the Canadian Immunization Research (CIRN) study
Authors: Gillis Hayley D , Lang Amanda L S , ElSherif May , Martin Irene , Hatchette Todd F , McNeil Shelly A , LeBlanc Jason J 
Published: June 2017

Study designDetection and serotyping ofStreptococcus pneumoniae areimportant to assess the impact of pneumococcal vaccines. This study describes the diagnostic accuracy of PCR-based detection ofS. pneumoniaedirectly from nasopharyngeal (NP) swabs collected for respiratory virus studies.MethodsActive surveillance for community-acquired pneumonia (CAP) in hospitalised adults was performed from December 2010 to 2013. Detection of pneumococcal CAP (CAPSpn) was performed by urine antigen detection (UAD), identification ofS. pneumoniaein sputum or blood cultures.S. pneumoniaewas detected in NP swabs usinglytAandcpsAreal-time PCR, and serotyping was performed using conventional and real-time multiplex PCRs. For serotyping, the Quellung reaction, PCR-based serotyping or a serotype-specific UAD was used.ResultsNP swab results were compared against CAP cases where all pneumococcal tests were performed (n=434), or where at least one test was performed (n=1616). CAPSpnwas identified in 22.1% (96/434) and 14.9% (240/1616), respectively. The sensitivity of NP swab PCR for the detection ofS. pneumoniaewas poor for CAPSpn(35.4% (34/96) and 34.17% (82/240)), but high specificity was observed (99.4% (336/338) and 97.89% (1347/1376)). Of the positive NP swabs, a serotype could be deduced by PCR in 88.2% (30/34) and 93.9% (77/82), respectively.ConclusionsWhile further optimisation may be needed to increase the sensitivity of PCR-based detection, its high specificity suggests there is a value for pneumococcal surveillance. With many laboratories archiving specimens for influenza virus surveillance, this specimen type could provide a non-culture-based method for pneumococcal surveillance.
A mixed-methods evaluation of the Educational Supervision Agreement for Wales
Authors: Webb Katie Louise , Bullock Alison , Groves Caroline , Saayman Anton Gerhard 
Published: June 2017

ObjectivesIn a bid to promote high-quality postgraduate education and training and support the General Medical Council’s (GMC) implementation plan for trainer recognition, the Wales Deanery developed the Educational Supervision Agreement (EdSA). This is a three-way agreement between Educational Supervisors, Local Education Providers and the Wales Deanery which clarifies roles, responsibilities and expectations for all. This paper reports on the formative evaluation of the EdSA after 1 year.DesignEvaluation of pan-Wales EdSA roll-out (2013–2015) employed a mixed-methods approach: questionnaires (n=191), interviews (n=11) with educational supervisors and discussion with key stakeholders (GMC, All-Wales Trainer Recognition Group, Clinical Directors). Numerical data were analysed in SPSS V.20; open comments underwent thematic content analysis.ParticipantsThe study involved Educational Supervisors working in different specialties across Wales, UK.ResultsAt the point of data collection, survey respondents represented 14% of signed agreements. Respondents believed the Agreement professionalises the Educational Supervisor role (85%, n=159 agreed), increases the accountability of Educational Supervisors (87%; n=160) and health boards (72%, n=131), provides leverage to negotiate supporting professional activities’ (SPA) time (76%, n=142) and continuing professional development (CPD) activities (71%, n=131). Factor analysis identified three principal factors: professionalisation of the educational supervisor role, supporting practice through training and feedback and implementation of the Agreement.ConclusionsOur evidence suggests that respondents believed the Agreement would professionalise and support their Educational Supervisor role. Respondents showed enthusiasm for the Agreement and its role in maintaining high standards of training.