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101.
Thomas?Durand Sophie?Jacob Laura?Lebouil Hassen?Douzane Philippe?Lestaevel Amithys?Rahimian Dimitri?Psimaras Lo?c?Feuvret Delphine?Leclercq Bruno?Brochet Radia?Tamarat Fabien?Milliat Marc?Benderitter Nicolas?Vayatis Georges?No?l Khê?Hoang-Xuan Jean-Yves?Delattre Damien?Ricard Marie-Odile?BernierEmail author 《BMC neurology》2015,15(1):261
Background
Radiotherapy is one of the most important treatments of primary and metastatic brain tumors. Unfortunately, it can involve moderate to severe complications among which leukoencephalopathy is very frequent and implies cognitive deficits such as memory, attention and executive dysfunctions. However, the incidence of this complication is not well established and the risk factors and process are poorly understood. The main objective of the study is to improve knowledge on radio-induced leukoencephalopathy based on pluridisciplinar approaches combining cognitive, biologic, imagery and dosimetric investigations.Method/Design
The EpiBrainRad study is a prospective cohort study including newly diagnosed high grade gliomas patients treated by radiotherapy and concomitant-adjuvant temozolomide chemotherapy. Patients are included between their surgery and first day of radio-chemotherapy, and the follow-up lasts for 3 years after treatment. Cognitive functioning assessments, specific blood biomarkers measures and magnetic resonance imagery are performed at different moment during the follow-up, and a specific dosimetric assessment of organs involved in the beam fields is performed. Firstly, leukoencephalopathy incidence rate will be estimated in this population. Secondly, correlations between cognitive impairments and dosimetry, biomarkers ranges and anomalies on imagery will be analyzed in order to better understand the onset and evolution of cognitive decrement associated with radiotherapy. Furthermore, a new cognitive test, quickly and easily performed, will be studied to determine its sensibility to detect leukoencephalopathy decrement.Discussion
With an original multidisciplinary approach, the EpiBrainRad study aims to improve knowledge on radio-induced leukoencephalopathy in order to improve its early diagnosis and prevention. The main challenge is to preserve quality-of-life after cancer treatments which imply to study the incidence of radiation-induced complications and their associated risk factors.Trial Registration
NCT02544178102.
Tran D Nadau A Durrieu G Ciret P Parisot JP Massabuau JC 《Chronobiology international》2011,28(4):307-317
The present study reports new insights into the complexity of environmental drivers in aquatic animals. The focus of this study was to determine the main forces that drive mollusc bivalve behavior in situ. To answer this question, the authors continuously studied the valve movements of permanently immersed oysters, Crassostrea gigas, during a 1-year-long in situ study. Valve behavior was monitored with a specially build valvometer, which allows continuously recording of up to 16 bivalves at high frequency (10?Hz). The results highlight a strong relationship between the rhythms of valve behavior and the complex association of the sun-earth-moon orbital positions. Permanently immersed C. gigas follows a robust and strong behavior primarily driven by the tidal cycle. The intensity of this tidal driving force is modulated by the neap-spring tides (i.e., synodic moon cycle), which themselves depend of the earth-moon distance (i.e., anomalistic moon cycle). Light is a significant driver of the oysters' biological rhythm, although its power is limited by the tides, which remain the predominant driver. More globally, depending where in the world the bivalves reside, the results suggest their biological rhythms should vary according to the relative importance of the solar cycle and different lunar cycles associated with tide generation. These results highlight the high plasticity of these oysters to adapt to their changing environment. 相似文献
103.
Dandoy Damien Fremaux Christophe Henry de Frahan Marie Horvath Philippe Boyaval Patrick Hols Pascal Fontaine Laetitia 《Microbial cell factories》2011,10(1):1-9
Background
FAD dependent glucose dehydrogenase (GDH) currently raises enormous interest in the field of glucose biosensors. Due to its superior properties such as high turnover rate, substrate specificity and oxygen independence, GDH makes its way into glucose biosensing. The recently discovered GDH from the ascomycete Glomerella cingulata is a novel candidate for such an electrochemical application, but also of interest to study the plant-pathogen interaction of a family of wide-spread, crop destroying fungi. Heterologous expression is a necessity to facilitate the production of GDH for biotechnological applications and to study its physiological role in the outbreak of anthracnose caused by Glomerella (anamorph Colletotrichum) spp.Results
Heterologous expression of active G. cingulata GDH has been achieved in both Escherichia coli and Pichia pastoris, however, the expressed volumetric activity was about 4800-fold higher in P. pastoris. Expression in E. coli resulted mainly in the formation of inclusion bodies and only after co-expression with molecular chaperones enzymatic activity was detected. The fed-batch cultivation of a P. pastoris transformant resulted in an expression of 48,000 U L-1 of GDH activity (57 mg L-1). Recombinant GDH was purified by a two-step purification procedure with a yield of 71%. Comparative characterization of molecular and catalytic properties shows identical features for the GDH expressed in P. pastoris and the wild-type enzyme from its natural fungal source.Conclusions
The heterologous expression of active GDH was greatly favoured in the eukaryotic host. The efficient expression in P. pastoris facilitates the production of genetically engineered GDH variants for electrochemical-, physiological- and structural studies. 相似文献104.
Mitochondria are cellular organelles involved in host-cell metabolic processes and the control of programmed cell death. A direct link between mitochondria and innate immune signalling was first highlighted with the identification of MAVS-a crucial adaptor for RIGI-like receptor signalling-as a mitochondria-anchored protein. Recently, other innate immune molecules, such as NLRX1, TRAF6, NLRP3 and IRGM have been functionally associated with mitochondria. Furthermore, mitochondrial alarmins-such as mitochondrial DNA and formyl peptides-can be released by damaged mitochondria and trigger inflammation. Therefore, mitochondria emerge as a fundamental hub for innate immune signalling. 相似文献
105.
The control of the mechanical stimuli transmitted to the cells is critical for the design of functional scaffolds for tissue
engineering. The objective of this study was to investigate the dynamics of the mechanical stimuli transmitted to the cells
during tissue differentiation in an irregular morphology scaffold under compressive load and perfusion flow. A calcium phosphate-based
glass porous scaffold was used. The solid phase and the fluid flow within the pores were modeled as linear elastic solid material
and Newtonian fluid, respectively. In the fluid model, different levels of viscosity were used to simulate tissue differentiation.
Compressive strain of 0.5% and fluid flow with constant inlet velocity of 10 μm/s or constant inlet pressure of 3 Pa were
applied. Octahedral shear strain and fluid shear stress were used as mechano-regulatory stimuli. For constant inlet velocity,
stimuli equivalent to bone were predicted in 80% of pore volume for the case of low tissue viscosity. For the cases of high
viscosity, fluctuations between stimuli equivalent to tissue formation and cell death were predicted due to the increase in
the fluid shear stress when tissue started to fill pores. When constant pressure was applied, stimuli equivalent to bone were
predicted in 62% of pore volume when low tissue viscosity was used and 42% when high tissue viscosity was used. This study
predicted critical variations of fluid shear stress when cells differentiated. If these variations are not controlled in vitro,
they can impede the formation of new matured tissue. 相似文献
106.
Patrelle C Ohst T Picard D Pagano A Sourice S Dallay MG Plötner J 《Molecular ecology resources》2011,11(1):200-205
We describe a non‐invasive, PCR‐RFLP‐based method that allows reliable determination of the European water frog species Pelophylax lessonae and Pelophylax ridibundus and the hybrid form Pelophylax esculentus. Maximum‐likelihood analysis of ITS2 sequences revealed two robust monophyletic clades corresponding to water frogs of the P. lessonae and P. ridibundus groups. Three restriction enzymes (KpnI, HaeII, and SmaI) were used to digest three conserved ITS2 domains. Taxonomic identification was unambiguous; the three restriction enzymes gave the same results. A French reference sample was identified using allozyme electrophoresis. Our PCR‐RFLP method confirmed circa 83% of identification of the allozyme method. We conclude that the difference between identifications was caused by introgression. 相似文献
107.
Johnson AA Kyriacou B Callahan DL Carruthers L Stangoulis J Lombi E Tester M 《PloS one》2011,6(9):e24476
Background
Rice is the primary source of food for billions of people in developing countries, yet the commonly consumed polished grain contains insufficient levels of the key micronutrients iron (Fe), zinc (Zn) and Vitamin A to meet daily dietary requirements. Experts estimate that a rice-based diet should contain 14.5 µg g−1 Fe in endosperm, the main constituent of polished grain, but breeding programs have failed to achieve even half of that value. Transgenic efforts to increase the Fe concentration of rice endosperm include expression of ferritin genes, nicotianamine synthase genes (NAS) or ferritin in conjunction with NAS genes, with results ranging from two-fold increases via single-gene approaches to six-fold increases via multi-gene approaches, yet no approach has reported 14.5 µg g−1 Fe in endosperm.Methodology/Principal Findings
Three populations of rice were generated to constitutively overexpress OsNAS1, OsNAS2 or OsNAS3, respectively. Nicotianamine, Fe and Zn concentrations were significantly increased in unpolished grain of all three of the overexpression populations, relative to controls, with the highest concentrations in the OsNAS2 and OsNAS3 overexpression populations. Selected lines from each population had at least 10 µg g−1 Fe in polished grain and two OsNAS2 overexpression lines had 14 and 19 µg g−1 Fe in polished grain, representing up to four-fold increases in Fe concentration. Two-fold increases of Zn concentration were also observed in the OsNAS2 population. Synchrotron X-ray fluorescence spectroscopy demonstrated that OsNAS2 overexpression leads to significant enrichment of Fe and Zn in phosphorus-free regions of rice endosperm.Conclusions
The OsNAS genes, particularly OsNAS2, show enormous potential for Fe and Zn biofortification of rice endosperm. The results demonstrate that rice cultivars overexpressing single rice OsNAS genes could provide a sustainable and genetically simple solution to Fe and Zn deficiency disorders affecting billions of people throughout the world. 相似文献108.
Matar-Merheb R Rhimi M Leydier A Huché F Galián C Desuzinges-Mandon E Ficheux D Flot D Aghajari N Kahn R Di Pietro A Jault JM Coleman AW Falson P 《PloS one》2011,6(3):e18036
Background
Membrane proteins are privileged pharmaceutical targets for which the development of structure-based drug design is challenging. One underlying reason is the fact that detergents do not stabilize membrane domains as efficiently as natural lipids in membranes, often leading to a partial to complete loss of activity/stability during protein extraction and purification and preventing crystallization in an active conformation.Methodology/Principal Findings
Anionic calix[4]arene based detergents (C4Cn, n = 1–12) were designed to structure the membrane domains through hydrophobic interactions and a network of salt bridges with the basic residues found at the cytosol-membrane interface of membrane proteins. These compounds behave as surfactants, forming micelles of 5–24 nm, with the critical micellar concentration (CMC) being as expected sensitive to pH ranging from 0.05 to 1.5 mM. Both by 1H NMR titration and Surface Tension titration experiments, the interaction of these molecules with the basic amino acids was confirmed. They extract membrane proteins from different origins behaving as mild detergents, leading to partial extraction in some cases. They also retain protein functionality, as shown for BmrA (Bacillus multidrug resistance ATP protein), a membrane multidrug-transporting ATPase, which is particularly sensitive to detergent extraction. These new detergents allow BmrA to bind daunorubicin with a Kd of 12 µM, a value similar to that observed after purification using dodecyl maltoside (DDM). They preserve the ATPase activity of BmrA (which resets the protein to its initial state after drug efflux) much more efficiently than SDS (sodium dodecyl sulphate), FC12 (Foscholine 12) or DDM. They also maintain in a functional state the C4Cn-extracted protein upon detergent exchange with FC12. Finally, they promote 3D-crystallization of the membrane protein.Conclusion/Significance
These compounds seem promising to extract in a functional state membrane proteins obeying the positive inside rule. In that context, they may contribute to the membrane protein crystallization field. 相似文献109.
Dubois D Pihet M Clec'h CL Croué A Beguin H Bouchara JP Chabasse D 《Mycopathologia》2005,160(2):117-123
Here we report a case of cutaneous alternariosis in a 74-year-old man treated by corticotherapy for myasthenia, and presenting
with papular, crusted lesions on the left elbow and the right knee. Histological examination of the biopsy specimens showed
fungal hyphae associated with round-shaped cells which were highly suggestive of alternariosis. Mycological culture allowed
the isolation of a dematiaceous fungus which was identified as a member of the Alternaria infectoria species-group. This was
confirmed by PCR amplification and sequencing of the internal transcribed spacer domain of the gene encoding nuclear ribosomal
DNA and of the mitochondrial small subunit ribosomal DNA domain. The fungus was therefore referred to the Scientific Institute
of Public Health where it was identified as Alternaria infectoria, on the basis of its very small 1 or 2-celled conidia often
arranged in long chains and presenting with very long secondary conidiophores. Corticotherapy was stopped and a local antifungal
treatment with ketoconazole was initiated, allowing the stabilisation of the cutaneous lesions within 2 months. 相似文献
110.
Beltz H Clauss C Piémont E Ficheux D Gorelick RJ Roques B Gabus C Darlix JL de Rocquigny H Mély Y 《Journal of molecular biology》2005,348(5):1113-1126