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81.
Renier A De Faria SM Jourand P Giraud E Dreyfus B Rapior S Prin Y 《Journal of experimental botany》2011,62(10):3693-3697
Crotalaria are plants of the Fabaceae family whose nodulation characteristics have been little explored despite the recent discovery of their unexpected ability to be efficiently nodulated in symbiosis with bacteria of the genus Methylobacterium. It has been shown that methylotrophy plays a key role in this unusual symbiotic system, as it is expressed within the nodule and as non-methylotroph mutants had a depleting effect on plant growth response. Within the nodule, Methylobacterium is thus able to obtain carbon both from host plant photosynthesis and from methylotrophy. In this context, the aim of the present study was to show the histological and cytological impacts of both symbiotic and methylotrophic metabolism within Crotalaria podocarpa nodules. It was established that if Crotalaria nodules are multilobed, each lobe has the morphology of indeterminate nodules but with a different anatomy; that is, without root hair infection or infection threads. In the fixation zone, bacteroids display a spherical shape and there is no uninfected cell. Crotalaria nodulation by Methylobacterium displayed some very unusual characteristics such as starch storage within bacteroid-filled cells of the fixation zone and also the complete lysis of apical nodular tissues (where bacteria have a free-living shape and express methylotrophy). This lysis could possibly reflect the bacterial degradation of plant wall pectins through bacterial pectin methyl esterases, thus producing methanol as a substrate, allowing bacterial multiplication before release from the nodule. 相似文献
82.
Mélanie L. Ferlazzo Laurène Sonzogni Adeline Granzotto Larry Bodgi Océane Lartin Clément Devic Guillaume Vogin Sandrine Pereira Nicolas Foray 《Molecular neurobiology》2014,49(3):1200-1211
Huntington’s disease (HD) is a neurodegenerative syndrome caused by mutations of the IT15 gene encoding for the huntingtin protein. Some research groups have previously shown that HD is associated with cellular radiosensitivity in quiescent cells. However, there is still no mechanistic model explaining such specific clinical feature. Here, we examined the ATM-dependent signaling and repair pathways of the DNA double-strand breaks (DSB), the key damage induced by ionizing radiation, in human HD skin fibroblasts. Early after irradiation, quiescent HD fibroblasts showed an abnormally low rate of recognized DSB managed by non-homologous end-joining reflected by a low yield of nuclear foci formed by phosphorylated H2AX histones and by 53BP1 protein. Furthermore, HD cells elicited a significant but moderate yield of unrepaired DSB 24 h after irradiation. Irradiated HD cells also presented a delayed nucleo-shuttling of phosphorylated forms of the ATM kinase, potentially due to a specific binding of ATM to mutated huntingtin in the cytoplasm. Our results suggest that HD belongs to the group of syndromes associated with a low but significant defect of DSB signaling and repair defect associated with radiosensitivity. A combination of biphosphonates and statins complements these impairments by facilitating the nucleo-shuttling of ATM, increasing the yield of recognized and repaired DSB. 相似文献
83.
Maité Garrouste-Orgeas Antoine Périer Philippe Mouricou Charles Grégoire Cédric Bruel Sandie Brochon Fran?ois Philippart Adeline Max Benoit Misset 《PloS one》2014,9(10)
Purpose
Keeping an ICU patient diary has been reported to benefit the patient''s recovery. Here, we investigated the families'' experience with reading and writing in patient ICU diaries kept by both the family and the staff.Methods
We conducted a qualitative study involving 32 semi-structured in-depth interviews of relatives of 26 patients (34% of all family members who visited patients) who met our ICU-diary criterion, i.e., ventilation for longer than 48 hours. Grounded theory was used to conceptualise the interview data via a three-step coding process (open coding, axial coding, and selective coding).Results
Communicative, emotional, and humanising experiences emerged from our data. First, family members used the diaries to access, understand, and assimilate the medical information written in the diaries by staff members, and then to share this information with other family members. Second, the diaries enabled family members to maintain a connection with the patient by documenting their presence and expressing their love and affection. Additionally, families confided in the diaries to maintain hope. Finally, family members felt the diaries humanized the medical staff and patient.Conclusions
Our findings indicate positive effects of diaries on family members. The diaries served as a powerful tool to deliver holistic patient- and family-centered care despite the potentially dehumanising ICU environment. The diaries made the family members aware of their valuable role in caring for the patient and enhanced their access to and comprehension of medical information. Diaries may play a major role in improving the well-being of ICU-patient families. 相似文献84.
Sophie Dupuis-Girod Alexis Ambrun Evelyne Decullier Géraldine Samson Adeline Roux Anne-Emmanuelle Fargeton Catherine Rioufol Verane Schwiertz Fran?ois Disant Fran?ois Chapuis Yves Donazzolo Gilles Paintaud Patrick Edery Frederic Faure 《MABS-AUSTIN》2014,6(3):793-798
Background: Hereditary hemorrhagic telangiectasia (HHT) is a dominantly inherited genetic vascular disorder in which epistaxis is the most frequent manifestation, responsible for high morbidity. Management of this symptom has no standard, and local treatments are often aggressive. Their efficacy is variable and has not been proven. Anti-angiogenic drugs, such as bevacizumab, are a new treatment strategy. Its systemic administration in patients with HHT improves liver damage-related symptoms and epistaxis. To limit the systemic adverse effects of bevacizumab and to ease administration, a local administration seems suitable. Primary objective: To evaluate the tolerance of increasing doses of bevacizumab administered as a nasal spray in patients with HHT-related epistaxis. Secondary objectives were to study the bioavailability and efficacy of bevacizumab against epistaxis when given as a nasal spray. Methodology: Phase 1, randomized, double-blind, placebo-controlled, monocentric study performed sequentially (dose escalation) on 5 groups of 8 patients. Each group was made up of 6 verum and 2 placebos. Five increasing doses of bevacizumab nasal spray (25 mg/mL) were evaluated: 12.5, 25, 50, 75 and 100 mg. Results: A total of 40 patients were included between October 2011 and October 2012. Bevacizumab nasal spray was well tolerated in all patients and the drug was not detected in their serum. No dose limiting toxicity was observed. No efficacy was observed at any dose in this study. Conclusion: Based on these results, bevacizumab nasal spray is a safe treatment of epistaxis in HHT. However, a randomized Phase 2 study is needed to determine its efficacy. Trial Registration: ClinicalTrials.gov Identifier # NCT01507480相似文献
85.
Substrate Specificity-Conferring Regions of the Nonribosomal Peptide Synthetase Adenylation Domains Involved in Albicidin Pathotoxin Biosynthesis Are Highly Conserved within the Species Xanthomonas albilineans 下载免费PDF全文
Adeline Renier Eric Vivien Stphane Cociancich Philippe Letourmy Xavier Perrier Philippe C. Rott Monique Royer 《Applied microbiology》2007,73(17):5523-5530
Albicidin is a pathotoxin produced by Xanthomonas albilineans, a xylem-invading pathogen that causes leaf scald disease of sugarcane. Albicidin is synthesized by a nonribosomal pathway via modular polyketide synthase and nonribosomal peptide synthetase (NRPS) megasynthases, and NRPS adenylation (A) domains are responsible for the recognition and activation of specific amino acid substrates. DNA fragments (0.5 kb) encoding the regions responsible for the substrate specificities of six albicidin NRPS A domains from 16 strains of X. albilineans representing the known diversity of this pathogen were amplified and sequenced. Polymorphism analysis of these DNA fragments at different levels (DNA, protein, and NRPS signature) showed that these pathogenicity loci were highly conserved. The conservation of these loci most likely reflects purifying selective pressure, as revealed by a comparison with the variability of nucleotide and amino acid sequences of two housekeeping genes (atpD and efp) of X. albilineans. Nevertheless, the 16 strains of X. albilineans were differentiated into several groups by a phylogenetic analysis of the nucleotide sequences corresponding to the NRPS A domains. One of these groups was representative of the genetic diversity previously found within the pathogen by random fragment length polymorphism and amplified fragment length polymorphism analyses. This group, which differed by three single synonymous nucleotide mutations, contained only four strains of X. albilineans that were all involved in outbreaks of sugarcane leaf scald. The amount of albicidin produced in vitro in agar and liquid media varied among the 16 strains of X. albilineans. However, no relationship among the amount of albicidin produced in vitro and the pathotypes and genetic diversity of the pathogen was found. The NRPS loci contributing to the synthesis of the primary structure of albicidin apparently are not involved in the observed pathogenicity differences among strains of X. albilineans. 相似文献
86.
Polysaccharide intercellular adhesin (PIA) protects Staphylococcus epidermidis against major components of the human innate immune system 总被引:4,自引:0,他引:4
Vuong C Voyich JM Fischer ER Braughton KR Whitney AR DeLeo FR Otto M 《Cellular microbiology》2004,6(3):269-275
The skin commensal and opportunistic pathogen Staphylococcus epidermidis is the leading cause of nosocomial and biofilm-associated infections. Little is known about the mechanisms by which S. epidermidis protects itself against the innate human immune system during colonization and infection. We used scanning electron microscopy to demonstrate that the exopolysaccharide intercellular adhesin (PIA) resides in fibrous strands on the bacterial cell surface, and that lack of PIA production results in complete loss of the extracellular matrix material that has been suggested to mediate immune evasion. Phagocytosis and killing by human polymorphonuclear leucocytes was significantly increased in a mutant strain lacking PIA production compared with the wild-type strain. The mutant strain was also significantly more susceptible to killing by major antibacterial peptides of human skin, cationic human beta-defensin 3 and LL-37, and anionic dermcidin. PIA represents the first defined factor of the staphylococcal biofilm matrix that protects against major components of human innate host defence. 相似文献
87.
Adeline Serckx Marie-Claude Huynen Jean-Fran?ois Bastin Alain Hambuckers Roseline C. Beudels-Jamar Marie Vimond Emilien Raynaud Hjalmar S. Kühl 《PloS one》2014,9(4)
A topic of major interest in socio-ecology is the comparison of chimpanzees and bonobos'' grouping patterns. Numerous studies have highlighted the impact of social and environmental factors on the different evolution in group cohesion seen in these sister species. We are still lacking, however, key information about bonobo social traits across their habitat range, in order to make accurate inter-species comparisons. In this study we investigated bonobo social cohesiveness at nesting sites depending on fruit availability in the forest-savannah mosaic of western Democratic Republic of Congo (DRC), a bonobo habitat which has received little attention from researchers and is characterized by high food resource variation within years. We collected data on two bonobo communities. Nest counts at nesting sites were used as a proxy for night grouping patterns and were analysed with regard to fruit availability. We also modelled bonobo population density at the site in order to investigate yearly variation. We found that one community density varied across the three years of surveys, suggesting that this bonobo community has significant variability in use of its home range. This finding highlights the importance of forest connectivity, a likely prerequisite for the ability of bonobos to adapt their ranging patterns to fruit availability changes. We found no influence of overall fruit availability on bonobo cohesiveness. Only fruit availability at the nesting sites showed a positive influence, indicating that bonobos favour food ‘hot spots’ as sleeping sites. Our findings have confirmed the results obtained from previous studies carried out in the dense tropical forests of DRC. Nevertheless, in order to clarify the impact of environmental variability on bonobo social cohesiveness, we will need to make direct observations of the apes in the forest-savannah mosaic as well as make comparisons across the entirety of the bonobos'' range using systematic methodology. 相似文献
88.
Grace G. Y. Lim Doreen S. K. Chua Adeline H. Basil Hui-Ying Chan Chou Chai Thiruma Arumugam Kah-Leong Lim 《The Journal of biological chemistry》2015,290(27):16882-16893
The potential cellular function of the 53-kDa cytosolic form of PINK1 (PINK1-53) is often overlooked because of its rapid degradation by the proteasome upon its production. Although a number of recent studies have suggested various roles for PINK1-53, how this labile PINK1 species attains an adequate expression level to fulfil these roles remains unclear. Here we demonstrated that PINK1-53 is stabilized in the presence of enhanced Lys-63-linked ubiquitination and identified TRAF6-related NF-κB activation as a novel pathway involved in this. We further showed that a mimetic of PINK1-53 promotes mitophagy but, curiously, in apparently healthy mitochondria. We speculate that this “non-selective” form of mitophagy may potentially help to counteract the build-up of reactive oxygen species in cells undergoing oxidative stress and, as such, represent a cytoprotective response. 相似文献
89.
90.
Anne-Sophie Marty Carole Burillon Adeline Desanlis Odile Damour Viridiana Kocaba Céline Auxenfans 《Cell and tissue banking》2016,17(2):225-232
Descemet Membrane Endothelial Keratoplasty (DMEK) selectively replaces the damaged posterior part of the cornea. However, the DMEK technique relies on a manually-performed dissection that is time-consuming, requires training and presents a potential risk of endothelial graft damages leading to surgery postponement when performed by surgeons in the operative room. To validate precut corneal tissue preparation for DMEK provided by a cornea bank in order to supply a quality and security precut endothelial tissue. The protocol was a technology transfer from the Netherlands Institute for Innovative Ocular Surgery (NIIOS) to Lyon Cornea Bank, after formation in NIIOS to the DMEK “no touch” dissection technique. The technique has been validated in selected conditions (materials, microscope) and after a learning curve, cornea bank technicians prepared endothelial tissue for DMEK. Endothelial cells densities (ECD) were evaluated before and after preparation, after storage and transport to the surgery room. Microbiological and histological controls have been done. Twenty corneas were manually dissected; 18 without tears. Nineteen endothelial grafts formed a double roll. The ECD loss after cutting was 3.3 % (n = 19). After transportation 7 days later, we found an ECD loss of 25 % (n = 12). Three days after cutting and transportation, we found 2.1 % of ECD loss (n = 7). Histology found an endothelial cells monolayer lying on Descemet membrane. The mean thickness was 12 ± 2.2 µm (n = 4). No microbial contamination was found (n = 19). Endothelial roll stability has been validated at 3 days in our cornea bank. Cornea bank technicians trained can deliver to surgeons an ECD controlled, safety and ready to use endothelial tissue, for DMEK by “no touch” technique, allowing time saving, quality and security for surgeons. 相似文献