Secondary metabolites a potential improvement for the economy of second generation biofuel production

The decreasing prices of oil ($29.44US – feb.2016) and natural gas ($1.97US– feb.2016) have significantly restrained the opportunity for the development of the second-generation biofuel industry. Numerous investigations focus on improving processes in order to improve the yield of biofuels. However, the latter being a commodity submitted to a strong competition by the fossil fuel industry, there is strong necessity to find other approaches allowing getting more revenues per tonne of converted biomass. Furthermore, despite the fact that the price of fossil fuels is decreasing, biomass still requires to be transported over long distances to reach a centralized conversion facility, thus, it is of outmost importance to get the most of this renewable feedstock. Secondary metabolites may represent an interesting way to generate complementary value to biofuels production. Extraction of secondary metabolites can 1) improve processes by removing undesirable compounds thus purifying the raw material (as an example by removing fermentation inhibitors) and 2) add an increased value by recovering high value compounds that could represent additional values as pharmaceuticals, cosmetics or food additives. Please click Additional Files below to see the full abstract

Refractive Errors Among Children at the Teaching Hospital of Bouaké (Central Côte d’Ivoire), from 2012 to 2016

Purpose: Contribute to a better understanding of refractive errors (or ametropias) among children in Côte d’Ivoire, at the epidemiological and clinical levels. Material and methods: Retrospective, cross-sectional descriptive study of medical records of children aged from 0 to 15 years received in ophthalmology consultation from January 1, 2012 to December 31, 2016. Whatever the reason for consultation, the clinical examination highlighted an error in the refraction.  Out of a total of 3,568 cases, 435 were selected. Results: The average age of patients was 12 years ± 0.6 (samples of 5- and 15-years extreme values) and children aged from 12 to 15 years represented 66.21% (n = 288).  There was a female predominance with 65.29% (n = 284) and 98.39% of them were students (n = 428).  The personal history of wearing corrective lenses was found in 4.83% (n = 21) while the family history of wearing corrective lenses was found in 3.91% of cases (n = 17). The most frequent reason for consultation was reduced visual acuity, but this represented only 17.45% of the reasons for consultation.  It was followed by photophobia (15.10%), and headaches (13, 50%).  All patients had benefited from an objective refraction study by automatic refractometry before optical correction, with documented evidence of cycloplegia with 0.5% Cyclopentolate in 53.8% of cases (n = 234). The refractive errors had a frequency of 12.2% and astigmatism, all forms combined (simple, compound, mixed), was present in 49.42% of patients (n = 215), followed by hyperopia with 33.1% (n = 144) and myopia with 17.47% (n = 76).  Refractive errors were classified as low in 96.55% of cases (n = 420) and strabismus was among 4 children, or 0.92% of the population under study. All these ametropias had benefited from an optical correction by glasses. Conclusion: Reducing the prevalence of uncorrected ametropia among children requires systematic screening, especially in schools.  However, the low representation of children of preschool or out-of-school age contributes to an underestimation of the real prevalence of refractive errors in our conditions

The Role of Power-to-Gas and Carbon Capture Technologies in Cross-Sector Decarbonisation Strategies

This paper proposes an optimisation-based framework to tackle long-term centralised planning problems of multi-sector, integrated energy systems including electricity, hydrogen, natural gas, synthetic methane and carbon dioxide. The model selects and sizes the set of power generation, energy conversion and storage as well as carbon capture technologies minimising the cost of supplying energy demand in the form of electricity, hydrogen, natural gas or synthetic methane across the power, heating, transportation and industry sectors whilst accounting for policy drivers, such as energy independence, carbon dioxide emissions reduction targets, or support schemes. The usefulness of the model is illustrated by a case study evaluating the potential of sector coupling via power-to-gas and carbon capture technologies to achieve deep decarbonisation targets in the Belgian context. Results, on the one hand, indicate that power-to-gas can only play a minor supporting role in cross-sector decarbonisation strategies in Belgium, as electrolysis plants are deployed in moderate quantities whilst methanation plants do not appear in any studied scenario. On the other hand, given the limited renewable potential, post-combustion and direct air carbon capture technologies clearly play an enabling role in any decarbonisation strategy, but may also exacerbate the dependence on fossil fuels

Evolution within a given virulence phenotype (pathotype) is driven by changes in aggressiveness: a case study of French wheat leaf rust populations

Plant pathogens are constantly evolving and adapting to their environment, including their host. Virulence alleles emerge, and then increase, and sometimes decrease in frequency within pathogen populations in response to the fluctuating selection pressures imposed by the deployment of resistance genes. In some cases, these strong selection pressures cannot fully explain the evolution observed in pathogen populations. A previous study on the French population of Puccinia triticina, the causal agent of wheat leaf rust, showed that two major pathotypes — groups of isolates with a particular combination of virulences — predominated but then declined over the 2005-2016 period. The relative dynamics and the domination of these two pathotypes — 166 317 0 and 106 314 0 —, relative to the other pathotypes present in the population at a low frequency although compatible, i.e. virulent on several varieties deployed, could not be explained solely by the frequency of Lr genes in the landscape. Within these two pathotypes, we identified two main genotypes that emerged in succession. We assessed three components of aggressiveness — infection efficiency, latency period and sporulation capacity — for 44 isolates representative of the four P. triticina pathotype-genotype combinations. We showed, for both pathotypes, that the more recent genotypes were more aggressive than the older ones. Our findings were highly consistent for the various components of aggressiveness for pathotype 166 317 0 grown on Michigan Amber — a ‘naive’ cultivar never grown in the landscape — or on Apache — a ‘neutral’ cultivar, which does not affect the pathotype frequency in the landscape and therefore was postulated to have no or minor selection effect on the population composition. For pathotype 106 314 0, the most recent genotype had a shorter latency period on several of the cultivars most frequently grown in the landscape, but not on ‘neutral’ and ‘naive’ cultivars. We conclude that the quantitative components of aggressiveness can be significant drivers of evolution in pathogen populations. A gain in aggressiveness stopped the decline in frequency of a pathotype, and subsequently allowed an increase in frequency of this pathotype in the pathogen population, providing evidence that adaptation to a changing varietal landscape not only affects virulence but can also lead to changes in aggressiveness

Histopathological Changes and Clinical Responses of Buruli Ulcer Plaque Lesions during Chemotherapy: A Role for Surgical Removal of Necrotic Tissue?

The tropical necrotizing skin disease Buruli ulcer (BU) caused by Mycobacterium ulcerans is associated with extensive tissue destruction and local immunosuppression caused by the macrolide exotoxin mycolactone. Chemotherapy with a combination of rifampicin and streptomycin for 8 weeks is the currently recommended treatment for all types of BU lesions, including both ulcerative and non-ulcerative stages (plaques, nodules and edema). Our histopathological analysis of twelve BU plaque lesions revealed extensive destruction of sub-cutaneous tissue. This frequently led to ulceration during antibiotic treatment. This should not be mistaken as a failure of the antimycobacterial chemotherapy, since we found no evidence for the persistence of active infection foci. Large necrotic areas were found to persist even after completion of antibiotic treatment. These may disturb wound healing and the role of wound debridement should therefore be formally tested in a clinical trial setting

Efficacy of vinblastine in central nervous system Langerhans cell histiocytosis: a nationwide retrospective study

<p>Abstract</p> <p>Background</p> <p>Vinblastine (VBL) is the standard treatment for systemic Langerhans cell histiocytosis (LCH), but little is known about its efficacy in central nervous system (CNS) mass lesions.</p> <p>Methods</p> <p>A retrospective chart review was conducted. Twenty patients from the French LCH Study Group register met the inclusion criteria. In brief, they had CNS mass lesions, had been treated with VBL, and were evaluable for radiologic response.</p> <p>Results</p> <p>The median age at diagnosis of LCH was 11.5 years (range: 1-50). Intravenous VBL 6 mg/m²was given in a 6-week induction treatment, followed by a maintenance treatment. The median total duration was 12 months (range: 3-30). Eleven patients received steroids concomitantly. Fifteen patients achieved an objective response; five had a complete response (CR: 25%), ten had a partial response (PR: 50%), four had stable disease (SD: 20%) and one patient progressed (PD: 5%). Of interest, four out of the six patients who received VBL without concomitant steroids achieved an objective response. With a median follow-up of 6.8 years, the 5-year event-free and overall survival was 61% and 84%, respectively. VBL was well-tolerated and there were no patient withdrawals due to adverse events.</p> <p>Conclusion</p> <p>VBL, with or without steroids, could potentially be a useful therapeutic option in LCH with CNS mass lesions, especially for those with inoperable lesions or multiple lesions. Prospective clinical trials are warranted for the evaluation of VBL in this indication.</p

Contribution of the community health volunteers in the control of buruli ulcer in Bénin

Buruli ulcer (BU) is a neglected tropical disease caused by Mycobacterium ulcerans. Usually BU begins as a painless nodule, plaque or edema, ultimately developing into an ulcer. The high number of patients presenting with ulcers in an advanced stage is striking. Such late presentation will complicate treatment and have long-term disabilities as a consequence. The disease is mainly endemic in West Africa. The primary strategy for control of this disease is early detection using community village volunteers.In this retrospective, observational study, information regarding Buruli ulcer patients that reported to one of the four BU centers in Bénin between January 2008 and December 2010 was collected using the WHO/BU01 forms. Information used from these forms included general characteristics of the patient, the results of diagnostic tests, the presence of functional limitations at start of treatment, lesion size, patient delay and the referral system. The role of the different referral systems on the stage of disease at presentation in the hospital was analyzed by a logistic regression analysis. About a quarter of the patients (26.5%) were referred to the hospital by the community health volunteers. In our data set, patients referred to the hospital by community health volunteers appeared to be in an earlier stage of disease than patients referred by other methods, but after adjustment by the regression analysis for the health center, this effect could no longer be seen. The Polymerase Chain Reaction (PCR) for IS2404 positivity rate among patients referred by the community health volunteers was not systematically lower than in patients referred by other systems.This study clarifies the role played by community health volunteers in Bénin, and shows that they play an important role in the control of BU

Family Relationship, Water Contact and Occurrence of Buruli Ulcer in Benin

Mycobacterium ulcerans disease (Buruli ulcer) is the most widespread mycobacterial disease in the world after leprosy and tuberculosis. How M. ulcerans is introduced into the skin of humans remains unclear, but it appears that individuals living in the same environment may have different susceptibilities. This case control study aims to determine whether frequent contacts with natural water sources, family relationship or the practice of consanguineous marriages are associated with the occurrence of Buruli ulcer (BU). The study involved 416 participants, of which 104 BU-confirmed cases and 312 age, gender and village of residence matched controls (persons who had no signs or symptoms of active or inactive BU). The results confirmed that contact with natural water sources is a risk factor. Furthermore, it suggests that a combination of genetic factors may constitute risk factors for the development of BU, possibly by influencing the type of immune response in the individual, and, consequently, the development of BU infection per se and its different clinical forms. These findings may be of major therapeutic interest