BackgroundV. carteri f. nagariensis constitutes, in its most simplified form, a cellularized spheroid built around and stabilised by a form of primitive extracellular matrix (ECM).MethodsWe developed a modular approach to soft tissue engineering, by compact stacking V. carteri-based building blocks. This approach is made possible by the structure and cell adhesive properties of these building blocks, which results from the composition of their algal ECM.ResultsA primary biocompatibility assessment demonstrated the cytocompatibility of the algal suspension, its histogenesis-promoting properties, and that it did not induce an inflammatory response in vitro. These results allowed us to consider the use of this algal suspension for soft tissue augmentation, and to initiate an in vivo biocompatibility study. V. carteri exhibited cellular fate-directing properties, causing (i) fibroblasts to take on an alkaline phosphatase+ stem-cell-like phenotype and (ii) both human adipose-derived stem cells and mouse embryonic stem cells to differentiate into preadipocytes to adipocytes. The ability of V. carteri to support histogenesis and adipogenesis was also observed in vivo by subcutaneous tissue augmentation of athymic mice, highlighting the potential of V. carteri to support or influence tissue regeneration.ConclusionsWe present for the first time V. carteri as an innovative and inspiring biomaterial for tissue engineering and soft tissue regeneration. Its strategies in terms of shape, structure and composition can be central in the design of a new generation of bio-inspired heterogeneous biomaterials recapitulating more appropriately the complexity of body tissues when guiding their regeneration.

The biomedical field still requires composite materials for medical devices and tissue engineering model design. As part of the pursuit of non-animal and non-proteic scaffolds, we propose here a cellulose-based material. In this study, 9%, 18% and 36% dialdehyde-functionalized microcrystalline celluloses (DAC) were synthesized by sodium periodate oxidation. The latter was subsequently coupled to PVA at ratios 1:2, 1:1 and 2:1 by dissolving in N-methyl pyrrolidone and lithium chloride. Moulding and successive rehydration in ethanol and water baths formed soft hydrogels. While oxidation effectiveness was confirmed by dialdehyde content determination for all DAC, we observed increasing hydrolysis associated with particle fragmentation. Imaging, FTIR and XDR analysis highlighted an intertwined DAC/PVA network mainly supported by electrostatic interactions, hemiacetal and acetal linkage. To meet tissue engineering requirements, an interconnected porosity was optimized using 0–50 µm salts. While the role of DAC in strengthening the hydrogel was identified, the oxidation ratio of DAC showed no distinct trend. DAC 9% material exhibited the highest indirect and direct cytocompatibility creating spheroid-like structures. DAC/PVA hydrogels showed physical stability and acceptability in vivo that led us to propose our DAC 9%/PVA based material for soft tissue graft application.

The influence of electromagnetic fields on bacterial denitrification has been tested on synthetic media with sludges from wastewater treatment stations, in batch mode. The effects of the intensity of the magnetic induction ratio B (mT), reaction volume and initial biomass concentration on the kinetics of the denitrification process were studied. Magnetic field had both an optimal stimulating effect on the activity of the denitrifying flora for B (mT)/mgx values of the order of 0.212, and an inhibitory effect for the values beyond the latter.Sludges underwent multiple exposure cycles to magnetic fields. It was shown that, after three exposure cycles, denitrification kinetics went from 6.5 to 12.7 mg N-NO3-L-1.h(-1) which corresponds to a 2.7 fold improvement. The improved performance persists even after the cessation of the magnetic field. Observation of the sludge by the environmental-electron microscope shows that the microbial population forming the starting sludge; changed following exposure to the magnetic field. The action of the; electromagnetic field on the microbial populations in denitrification resulted in the modification of the diversity of the flora that is initially present, favoring the development of Proteo bacteria, particularly the Betaproteo bacteria subclass, which results in improved denitrification. (C) 2020 Elsevier Ltd. All rights reserved.

The growing uses of functional polymers in different domains and the well-established remanence of synthetic polymers underline the necessity to study their microbial biodegradation. A phylloplane bacterial collection was screened for its potential to overcome documented factors limiting polymer biodegradation, i.e. low cleavable long chain linear polymers and low bioavailable hydrophobic compounds. Acrylate-based polymers, namely poly (2-hydroxyethyl methacrylate) (pHEMA), poly(N-isopropylacrylamide) (pNIPAM), poly(acrylamide) (pAM) and poly(acrylic acid sodium salt) (pAS), and a hydrophobic crosslinker Epoxidized Soybean Oil Acrylate (ESOA) were used as selective substrates. OD monitoring of growth with these molecules as sole carbon sources were correlated with substrates alterations determined by H-1 NMR, GPC and FTIR. Selected strains belong to Bacillales Family XII. Incertae Sedis, Bacillaceae, Nocardiaceae, Micrococcaceae, Entembacteriaceae and Pseudomonadaceae. Bacillus species mainly developed with ESOA. Exiguobacterium sibiricum strains could grow with pHEMA and pNIPAM leading to polymer molecular weight decreases. Arthrobacter koreensis showed the highest alteration capacities of pHEMA with molecular weight decreases from 22,000 to 3,148 g/mol and the production of presumed aromatics and carbon chains.

Conjugated linoleic acids (CLAs) have been found to have beneficial effects on human health when used as dietary supplements. However, their availability is limited because pure, chemistry-based production is expensive, and biology-based fermentation methods can only create small quantities. In an effort to enhance microbial production of CLAs, four genetically modified strains of the oleaginous yeast Yarrowia lipolytica were generated. These mutants presented various genetic modifications, including the elimination of β-oxidation (pox1-6∆), the inability to store lipids as triglycerides (dga1∆ dga2∆ are1∆ lro1∆), and the overexpression of the Y. lipolytica ∆12-desaturase gene (YlFAD2) under the control of the constitutive pTEF promoter. All strains received two copies of the pTEF-oPAI or pPOX-oPAI expression cassettes; PAI encodes linoleic acid isomerase in Propionibacterium acnes. The strains were cultured in neosynthesis or bioconversion medium in flasks or a bioreactor. The strain combining the three modifications mentioned above showed the best results: when it was grown in neosynthesis medium in a flask, CLAs represented 6.5% of total fatty acids and in bioconversion medium in a bioreactor, and CLA content reached 302 mg/L. In a previous study, a CLA degradation rate of 117 mg/L/h was observed in bioconversion medium. Here, by eliminating β-oxidation, we achieved a much lower rate of 1.8 mg/L/h.

Reduction of nitrate to nitrogen is critical for wastewater treatment process. The present work proposed a promising approach to improve the activity of denitrifying activated sludge by using low frequency ultrasonic treatment. Batch activity assays showed that when ultrasound was applied, denitrification performance was 2.64 higher than the control. Kinetic analysis of nitrate removal rate versus ultrasonic power and duty cycle was performed to investigate the effect of operational parameters on activated sludge activities. The best stimulating effect was observed at 40 W ultrasonic power and 40% duty cycle. The above results demonstrated that ultrasonic stimulation can be used as a technique for enhancing bacterial activities for water treatment. Studies of other parameters that also affect the denitrification under ultrasound are under way.

Having a glimpse of the relationships between the zinc and cadmium hyper accumulator Arabidopsis halleri and its rhizospheric bacteria may represent an interesting step towards the implementation of a rhizoremediation strategy based on this plant. Until now, these relationships remained unraveled. This work aimed to give some insights into the composition of the bacterial communities surrounding A. halleri when it grows on a soil harboring elevated amounts of zinc and cadmium, as well as into the influence that plant roots may exert on them. Industrial highly polluted soils containing different amounts of zinc and cadmium and surrounding A. halleri plants were sampled and their bacterial contents were harvested at various distances from A. halleri root system. Genetic diversity was assessed through DNA extraction, PCR amplification, 16S rDNA libraries construction, RFLP analysis and partial sequencing. Nine mini-libraries of hundred clones each were established and analyzed. Up to 481 independent clones were sequenced and identified at genus level. Twelve genera among 48 were found particularly well represented in the different sub-fractions analyzed. At class level, ten different classes were identified. Alpha-proteobacteria, Gamma-proteobacteria, Flavobacteria and Sphingobacteria were the main contributors to flora diversity. In the less polluted soil, roots proximity seems to affect negatively Alpha-proteobacteria and Flavobacteria and positively Gamma-proteobacteria. A rhizospheric selection limited to some specific genera was also observed when pollution raised. (C) 2013 Elsevier Masson SAS. All rights reserved.

Plants-microorganisms interactions play a fundamental role in terrestrial ecosystems and various methods have been reported for plant-associated bacteria extraction. However, these methods exhibit notable variations and lack of some procedural details that may impact the interpretations of results. We propose here a standardized and detailed protocol for the independent extraction of bulk, rhizosphere and rhizoplan soil fractions. This protocol was applied to the sampling of different polluted soil fractions collected in the vicinity of Arabidopsis halleri dense root system. It allowed us to determine the cultivable bacterial densities in each fraction and to confirm the existence of a bacterial gradient linked to roots distance, with a higher amount of bacteria in the rhizospheric area. We suggest to use this unified procedure as a common basis for soil sampling and bacterial communities analysis from other roots systems.

The development of optimal in situ bioremediation strategies requires a better knowledge of their impact on the soil microbial communities. We have evaluated the impact of hexadecane contamination and different nutrient amendments on soil microbial density and activity. Microbial density was measured via total DNA quantification, and microbial activity via respiration and RNA variation. The RNA/DNA ratio was also determined, as it is a potential indicator of microbial activity. PCR-amplified 16S rRNA genes were cloned and sequenced to analyze the diversity of bacterial communities. Nutrient addition significantly increased respiration and DNA and RNA concentrations in contaminated soil, indicating a limitation of degradation and growth by the availability of nitrogen and phosphorus in unamended microcosms. Hexadecane treatment slightly affected the diversity of the bacterial community, while it was dramatically reduced by nutrient treatments, particularly the addition of nitrogen and phosphorus. Microbial community composition was also altered with the enrichment of populations related to Nocardia in bioremediated soils, while uncultured Proteobacteria were mostly detected in uncontaminated soil.

Programmed cell death (PCD), a fundamental process that can be triggered in all cells, was supposed until recently solely centred on the mitochondrion. However, in amitochondriate organisms where only hydrogenosomes and mitosomes subsist as mitochondria relics, recent findings show that PCD still occurs. This exciting discovery is presented here in the light of the development of sequencing project in various different species as well as recent findings about mitochondrial derivates and ancestral viruses, contributing to a better understanding of the life tree as well as to the future discovery of new molecules of interest.

In order to generate an immune response against myeloma cells in an homogenous murine model, a stable hybrid cell line (DCSp) was established through the syngenic fusion between mouse dendritic cells (DC) and mouse Sp2/0 myeloma cells. DCSp cells behaved as potent T cell stimulators and were able to induce Sp2/0 specific cytotoxicity. When mice were immunized with irradiated hybrids before SP2/0 injection, they exhibited a significantly higher rate of survival as compared with controls. When tumors were detected, their emergence was not delayed, and time elapsed between tumor clinical perception and death remained unchanged. A humoral immune response was also always associated. We assume that this stable dendritoma cell line can be considered a valuable tool for myeloma studies in an homogenous mouse model. The efficiency of dendritoma as a weapon against tumor cells and the benefit of syngeny in experimental models are discussed.

A bstract : Some protozoans, such as Trichomonad species, do not possess mitochondria. Most of the time, they harbor another type of membrane‐bounded organelle, called hydrogenosome from its capacity to produce H 2 . This is the case for the human parasite Trichomonas vaginalis . Some other parasites, such as the protist Giardia lamblia , do not harbor any of these organelles. From this observation arises naturally a naive question: How do cells die when the mitochondrion, the cornerstone of apoptotic process, is absent? Data strongly suggest that the mitochondrion and the hydrogenosome arose from a common ancestral endosymbiont. But hydrogenosomes do not appear to directly substitute for mitochondria in apoptotic functions. Thus, it appears judicious to examine more closely the genome of unicellular cells, which do not harbor mitochondria, and search for new molecules that could participate in the apoptotic process in these microorganisms.

In multicellular organisms and in all protozoans harbouring mitochondria, the pathways leading to programmed cell death (PCD) are localized in the mitochondria. Intriguingly, unicellular parasites devoid of mitochondria such as Trichomonas vaginalis and Giardia intestinalis undergo a form of cell death resembling apoptosis, the most frequent form of PCD. This reinforces the idea that PCD must have evolved before the evolution of multicellularity. Moreover, this leads to the hypothesis of an early emergence of death pathways in eukaryotes preceding mitochondrial endosymbiosis and brings into question the central role of mitochondria in PCD.

808 > Depuis 1995, l’abondante litterature scientifique a confirme une implication directe ou indirecte de la mitochondrie dans la mort cellulaire programmee. Cette implication a ete particulierement bien etudiee pour le processus apoptotique, au cours duquel deux grandes voies ont ete decrites. L’une, dependante des caspases, fait intervenir le cytochrome c, une proteine mitochondriale liberee a cet effet vers le cytosol. L’autre, independante des caspases, implique la proteine mitochondriale AIF (apoptosis inhibiting factor) [1, 2]. Tout laisse donc penser que la mitochondrie joue un role majeur, sinon primordial, dans la mise en place de la mort cellulaire programmee. Qu’en est-il alors de la mort cellulaire programmee chez les organismes unicellulaires depourvus de mitochondries ? Est-il possible qu’une ou plusieurs voies alternatives non mitochondriales puissent aboutir au meme resultat dans ces organismes ? Nous avons recemment pu demontrer [3] qu’il est possible de declencher, chez le protiste* Trichomonas vaginalis depourvu de mitochondries, une forme de mort cellulaire morphologiquement distincte de la necrose. Curieusement, certaines de ses caracteristiques ressemblent tres nettement a celles du processus apoptotique et d’autres en sont totalement distinctes (Tableau I). L’analyse des cellules en epifluorescence permet d’observer chez T. vaginalis les differentes formes de condensation chromatinienne decrites au cours de la mort cellulaire programmee des organismes unicellulaires et multicellulaires mitochondriaux. Ces formes sont communes aux processus d’apoptose et de para-apoptose, une variante de mort cellulaire programmee recemment decrite [4] (Tableau I) (➜). Le gonflement de la membrane cellulaire et la partition finale du contenu genomique (decrit dans l’apoptose comme « corps apoptotiques ») sont egalement presents. L’exposition des groupements phosphatidyl-serine lies a l’annexine V a la surface externe de la membrane constitue un point commun supplementaire. Tous ces elements sont observables de maniere reproductible aussi bien dans les cellules traitees par des drogues proapoptotiques (etoposide, staurosporine, doxorubicine), que dans celles exposees au metronidazole (agent therapeutique utilise dans les infections a T. vaginalis) ou a un stress nutritif. Sur un plan genomique, l’apoptose dependante des caspases aboutit a une fragmentation de l’ADN par des coupures recurrentes tous les 180 nucleotides (fragmentation oligonucleosomique). L’analyse par electrophorese de cet ADN montre un profil de migration caracteristique « en echelle ». Dans le cas de NOUVELLE

A monoclonal antibody 9G4H9 that exhibits a beta-lactamase-like activity was previously obtained in accordance with the idiotypic network theory. This abzyme presents the most catalytic efficiency in amidase activity described in literature (kcat = 0.9 min-1). Some reports have demonstrated that functionality as complex as catalysis may be mimicked in this way. Comparison of the catalytic properties of both enzyme and abzyme previously allowed us to obtain better knowledge about 9G4H9 abzymatic machinery. In attempt to characterize this abzyme, the variable regions of kappa and heavy chain were cloned. We present a 'universal' method to clone the correct Vkappa gene to bypass aberrant Vkappa (abVkappa) produced by MOPC-21-derived hybridomas. Sequences obtained are compared in the GenBank database. The VH and Vkappa genes present some important sequence homology with autoantibodies suggesting a direct relationship between catalytic anti-idiotypic antibody and autoimmunity.

Adrenoleukodystrophy (ALD), a severe demyelinating disease, is caused by mutations in a gene coding for a peroxisomal membrane protein (ALDP), which belongs to the superfamily of ATP binding cassette (ABC) transporters and has the structure of a half transporter. ALDP showed 38% sequence identity with another peroxisomal membrane protein, PMP70, up to now its closest homologue. We describe here the cloning and characterization of a mouse ALD-related gene (ALDR), which codes for a protein with 66% identity with ALDP and shares the same half transporter structure. The ALDR protein was overexpressed in COS cells and was found to be associated with the peroxisomes. The ALD and ALDR genes show overlapping but clearly distinct expression patterns in mouse and may thus play similar but nonequivalent roles. The ALDR gene, which appears highly conserved in man, is a candidate for being a modifier gene that could account for some of the extreme phenotypic variability of ALD. The ALDR gene is also a candidate for being implicated in one of the complementation groups of Zellweger syndrome, a genetically heterogeneous disorder of peroxisome biogenesis, rare cases of which were found to be associated with mutations in the PMP70 (PXMP1) gene.

X-linked adrenoleukodystrophy (ALD), a neurodegenerative disorder associated with impaired beta-oxidation of very-long-chain fatty acids (VLCFA), is due to mutations in a gene encoding a peroxisomal ATP-binding cassette (ABC) transporter (ALD protein [ALDP]). We analyzed the open reading frame of the ALD gene in 44 French ALD kindred by using SSCP or denaturing gradient-gel electrophoresis and studied the effect of mutations on ALDP by immunocytofluorescence and western blotting of fibroblasts and/or white blood cells. Mutations were detected in 37 of 44 kindreds and were distributed over the whole protein-coding region, with the exception of the C terminus encoded in exon 10. Except for two mutations (delAG1801 and P560L) observed four times each, nearly every ALD family has a different mutation. Twenty-four of 37 mutations were missense mutations leading to amino acid changes located in or close to putative transmembrane segments (TMS 2, 3, 4, and 5), in the EAA-like motif and in the nucleotide fold of the ATP-binding domain of ALDP. Of 38 ALD patients tested, 27 (71%) lacked ALDP immunoreactivity in their fibroblasts and/or white blood cells. More than half of missense mutations studied (11 of 21) resulted in a complete lack of ALDP immunoreactivity, and six missense mutations resulted in decreased ALDP expression. The fibroblasts and/or white blood cells of 15 of 15 heterozygous carrier from ALD kindred with no ALDP showed a mixture of positive- and negative-ALDP immunoreactivity due to X-inactivation. Since 5%-15% of heterozygous women have normal VLCFA levels, the immunodetection of ALDP in white blood cells can be applicable in a majority of ALD kindred, to identify heterozygous women, particularly when the ALD gene mutation has not yet been identified.

Human MutationVolume 6, Issue 3 p. 272-273 Mutation in Brief Two intronic mutations in the adrenoleukodystrophy gene Stephan Kemp, Corresponding Author Stephan Kemp Department of Neurology, Academic Medical Center, 1105 AZ, Amsterdam, The NetherlandsDepartment of Neurology, Academic Medical Center, 1105 AZ, Amsterdam, The NetherlandsSearch for more papers by this authorMarjolijn J. L. Ligtenberg, Marjolijn J. L. Ligtenberg Department of Human Genetics, University Hospital Nijmegen, 6500 HB, Nijmegen, The NetherlandsSearch for more papers by this authorBjörn M. van Geel, Björn M. van Geel Department of Neurology, Academic Medical Center, 1105 AZ, Amsterdam, The NetherlandsSearch for more papers by this authorPeter G. Barth, Peter G. Barth Department of Neurology, Academic Medical Center, 1105 AZ, Amsterdam, The NetherlandsSearch for more papers by this authorClaude-Olivier Sarde, Claude-Olivier Sarde Laboratoire de Génétique Moléculaire des Eucaryotes, Unité 184 de L'INSERM, Faculté de Médecine et CHRU, 67085 Strasbourg Cedex, France; Fax 31-20-697-1438Search for more papers by this authorBernard A. van Oost, Bernard A. van Oost Department of Human Genetics, University Hospital Nijmegen, 6500 HB, Nijmegen, The NetherlandsSearch for more papers by this authorPieter A. Bolhuis, Pieter A. Bolhuis Department of Neurology, Academic Medical Center, 1105 AZ, Amsterdam, The NetherlandsSearch for more papers by this author Stephan Kemp, Corresponding Author Stephan Kemp Department of Neurology, Academic Medical Center, 1105 AZ, Amsterdam, The NetherlandsDepartment of Neurology, Academic Medical Center, 1105 AZ, Amsterdam, The NetherlandsSearch for more papers by this authorMarjolijn J. L. Ligtenberg, Marjolijn J. L. Ligtenberg Department of Human Genetics, University Hospital Nijmegen, 6500 HB, Nijmegen, The NetherlandsSearch for more papers by this authorBjörn M. van Geel, Björn M. van Geel Department of Neurology, Academic Medical Center, 1105 AZ, Amsterdam, The NetherlandsSearch for more papers by this authorPeter G. Barth, Peter G. Barth Department of Neurology, Academic Medical Center, 1105 AZ, Amsterdam, The NetherlandsSearch for more papers by this authorClaude-Olivier Sarde, Claude-Olivier Sarde Laboratoire de Génétique Moléculaire des Eucaryotes, Unité 184 de L'INSERM, Faculté de Médecine et CHRU, 67085 Strasbourg Cedex, France; Fax 31-20-697-1438Search for more papers by this authorBernard A. van Oost, Bernard A. van Oost Department of Human Genetics, University Hospital Nijmegen, 6500 HB, Nijmegen, The NetherlandsSearch for more papers by this authorPieter A. Bolhuis, Pieter A. Bolhuis Department of Neurology, Academic Medical Center, 1105 AZ, Amsterdam, The NetherlandsSearch for more papers by this author First published: 1995 https://doi.org/10.1002/humu.1380060316Citations: 9AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article.Citing Literature Volume6, Issue31995Pages 272-273 RelatedInformation