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1.
Arch Microbiol ; 205(5): 194, 2023 Apr 15.
Article in English | MEDLINE | ID: mdl-37061655

ABSTRACT

In esca disease affecting grapevines, Phaeomoniella chlamydospora and Phaeoacremonium minimum colonize the woody parts of the trunks and arms, where they obtain nutrition from xylem sap and, potentially, from residues resulting from the enzymatic breakdown of lignified cell walls, particularly osidic residues. We quantified the secretion of lignin peroxidase, manganese peroxidase and laccase by these fungi in woody tissues of selectively infected cuttings using immunolabeling and transmission electron microscopy. Our results indicated that the detection of these enzymes was generally higher in tissues infected with Phaeoacremonium minimum. These data were confirmed through immunodetection of enzymes secreted by hyphae of fungi grown in vitro. Additionally, we observed that the supply of various carbohydrates (mono, di, tri and tetrasaccharides and polymers) differentially influenced fungal growth and polypeptide secretion. Since some secreted polypeptides display detrimental effects on grapevine cells, these results raise the question of whether the carbohydrate environment could be a factor affecting the aggressiveness of these pathogens.


Subject(s)
Vitis , Wood , Wood/microbiology , Plant Diseases/microbiology , Vitis/microbiology , Carbohydrates
2.
Clin Imaging ; 84: 118-129, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35183916

ABSTRACT

Cystic Fibrosis (CF) is the most common lethal genetic disorder in Caucasian populations, affecting roughly 70,000 individuals worldwide. This autosomal recessive disorder causes a wide spectrum of multisystemic manifestations, most of which are either directly or indirectly related to defective epithelial chloride secretion. The current median life expectancy is 44 years; however, a significant proportion of the CF population now live into the 5th decade and beyond due to advances in treatment. As life expectancy of CF patients increases, there is a newly emerging adult CF population with unique radiological manifestations spanning multiple organ systems, which often require follow-up imaging. The goal of this article is to review the multiple systemic manifestations and complications of CF on different imaging modalities and explore the appropriate radiological follow up recommended.


Subject(s)
Cystic Fibrosis , Adult , Cystic Fibrosis/complications , Cystic Fibrosis/diagnostic imaging , Cystic Fibrosis/genetics , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Humans , Radiography , Radiologists
3.
Front Plant Sci ; 12: 681929, 2021.
Article in English | MEDLINE | ID: mdl-34552602

ABSTRACT

Carbon management by plants involves the activity of many sugar transporters, which play roles in sugar subcellular partitioning and reallocation at the whole organism scale. Among these transporters, the early response to dehydration six-like (ESL) monosaccharide transporters (MSTs) are still poorly characterized although they represent one of the largest sugar transporter subfamilies. In this study, we used an evolutionary genomic approach to infer the evolutionary history of this multigenic family. No ESL could be identified in the genomes of rhodophytes, chlorophytes, and the brown algae Ectocarpus siliculosus, whereas one ESL was identified in the genome of Klebsormidium nitens providing evidence for the early emergence of these transporters in Streptophytes. A phylogenetic analysis using the 519 putative ESL proteins identified in the genomes of 47 Embryophyta species and being representative of the plant kingdom has revealed that ESL protein sequences can be divided into three major groups. The first and second groups originated in the common ancestor of all spermaphytes [ζ: 340 million years ago (MYA)] and of angiosperms (ε: 170-235 MYA), respectively, and the third group originated before the divergence of rosids and asterids (γ/1R: 117 MYA). In some eudicots (Vitales, Malpighiales, Myrtales, Sapindales, Brassicales, Malvales, and Solanales), the ESL family presents remarkable expansions of gene copies associated with tandem duplications. The analysis of non-synonymous and synonymous substitutions for the dN/dS ratio of the ESL copies of the genus Arabidopsis has revealed that ESL genes are evolved under a purifying selection even though the progressive increase of dN/dS ratios in the three groups suggests subdiversification phenomena. To further explore the possible acquisition of novel functions by ESL MSTs, we identified the gene structure and promoter cis-acting elements for Arabidopsis thaliana ESL genes. The expression profiling of Arabidopsis ESL unraveled some gene copies that are almost constitutively expressed, whereas other gene copies display organ-preferential expression patterns. This study provides an evolving framework to better understand the roles of ESL transporters in plant development and response to environmental constraints.

4.
Front Plant Sci ; 12: 708876, 2021.
Article in English | MEDLINE | ID: mdl-34484269

ABSTRACT

Drought is one of the main abiotic stresses, which affects plant growth, development, and crop yield. Plant response to drought implies carbon allocation to sink organs and sugar partitioning between different cell compartments, and thereby requires the involvement of sugar transporters (SUTs). Among them, the early response to dehydration six-like (ESL), with 19 members in Arabidopsis thaliana, form the largest subfamily of monosaccharide transporters (MSTs) still poorly characterized. A common feature of these genes is their involvement in plant response to abiotic stresses, including water deficit. In this context, we carried out morphological and physiological phenotyping of A. thaliana plants grown under well-watered (WW) and water-deprived (WD) conditions, together with the expression profiling of 17 AtESL genes in rosette leaves. The drought responsiveness of 12 ESL genes, 4 upregulated and 8 downregulated, was correlated to different water statuses of rosette leaves. The differential expression of each of the tandem duplicated AtESL genes in response to water stress is in favor of their plausible functional diversity. Furthermore, transfer DNA (T-DNA) insertional mutants for each of the four upregulated ESLs in response to water deprivation were identified and characterized under WW and WD conditions. To gain insights into global sugar exchanges between vacuole and cytosol under water deficit, the gene expression of other vacuolar SUTs and invertases (AtTMT, AtSUC, AtSWEET, and AtßFRUCT) was analyzed and discussed.

5.
J Exp Bot ; 71(22): 7301-7315, 2020 12 31.
Article in English | MEDLINE | ID: mdl-32860502

ABSTRACT

Plants live in close relationships with complex populations of microorganisms, including rhizobacterial species commonly referred to as plant growth-promoting rhizobacteria (PGPR). PGPR are able to improve plant productivity, but the molecular mechanisms involved in this process remain largely unknown. Using an in vitro experimental system, the model plant Arabidopsis thaliana, and the well-characterized PGPR strain Pseudomonas simiae WCS417r (PsWCS417r), we carried out a comprehensive set of phenotypic and gene expression analyses. Our results show that PsWCS417r induces major transcriptional changes in sugar transport and in other key biological processes linked to plant growth, development, and defense. Notably, we identified a set of 13 genes of the SWEET and ERD6-like sugar transporter gene families whose expression is up- or down-regulated in response to seedling root inoculation with the PGPR or exposure to their volatile compounds. Using a reverse genetic approach, we demonstrate that SWEET11 and SWEET12 are functionally involved in the interaction and its plant growth-promoting effects, possibly by controlling the amount of sugar transported from the shoot to the root and to the PGPR. Altogether, our study reveals that PGPR-induced beneficial effects on plant growth and development are associated with changes in plant sugar transport.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis/genetics , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Membrane Transport Proteins , Plant Roots/metabolism , Pseudomonas/metabolism , Sugars
6.
FEBS Open Bio ; 8(5): 784-798, 2018 May.
Article in English | MEDLINE | ID: mdl-29744293

ABSTRACT

A novel biological model was created for the comparison of grapevine embryogenic cells (EC) and nonembryogenic cells (NEC) sharing a common genetic background but distinct phenotypes, when cultured on their respective most appropriate media. Cytological characterization, 1H-NMR analysis of intracellular metabolites, and glycolytic enzyme activities provided evidence for the marked metabolic differences between EC and NEC. The EC were characterized by a moderate and organized cell proliferation, coupled with a low flux through glycolysis, high capacity of phosphoenolpyruvate carboxylase and glucokinase, and high oxygen consumption. The NEC displayed strong anarchic growth, and their high rate of glycolysis due to the low energetic efficiency of the fermentative metabolism is confirmed by increased enolase capacity and low oxygen consumption.

7.
J Vasc Interv Radiol ; 28(8): 1090-1097, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28629928

ABSTRACT

PURPOSE: To evaluate the safety and efficacy of endovascular fiducial markers (EVFMs) for CyberKnife stereotactic radiation therapy (RT) of malignant lung neoplasms in patients with contraindications to percutaneous fiducial marker (PTFM) placement. MATERIALS AND METHODS: Between January 2011 and December 2013, 15 patients (7 men and 8 women) aged 59-87 years (mean, 73 y) underwent EVFM placement and 109 patients (54 men and 55 women) aged 55-92 years (mean, 73 y) underwent 114 PTFM placements. All patients who received EVFMs had contraindications to PTFM insertion. Complications were recorded for all 129 procedures. Proportions of markers used for CyberKnife stereotactic RT planning and distance between markers and tumor were assessed in all 15 patients in the EVFM group and in 15 randomly selected patients in the PTFM group. RESULTS: Sixty-two EVFMs and 56 PTFMs were inserted in the groups of 15 patients. CyberKnife stereotactic RT was not performed in 2 EVFM recipients (8 EVFMs) and 1 PTFM recipient (4 PTFMs). CyberKnife stereotactic RT was planned with the use of 39 of 54 EVFMs (72%) in 13 patients and 37 of 52 PTFMs (71%) in 14 patients. Mean distances between the tumor and EVFMs and PTFMs were 5.5 mm and 2.7 mm, respectively (P = .0152). No complications occurred in the EVFM group. In the PTFM group, 60 of 114 patients (52.6%) had small or moderate pneumothoraxes, 13 (11.4%) had chest tubes inserted, and 5 (4.4%) had self-limiting hemoptysis. CONCLUSIONS: EVFM is feasible and safe, and may therefore offer an alternative when patients are not candidates for percutaneous marker placement.


Subject(s)
Fiducial Markers , Lung Neoplasms/radiotherapy , Radiosurgery/methods , Aged , Aged, 80 and over , Equipment Safety , Female , Humans , Male , Middle Aged , Radiosurgery/instrumentation , Treatment Outcome
8.
Protoplasma ; 242(1-4): 69-80, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20237812

ABSTRACT

We studied the distribution of wall ingrowth (WI) polymers by probing thin sections of companion cells specialized as transfer cells in minor veins of Medicago sativa cv Gabès blade with affinity probes and antibodies specific to polysaccharides and glycoproteins. The wall polymers in the controls were similar in WIs and in the primary wall but differently distributed. The extent of labeling in these papillate WIs differed for JIM5 and JIM7 homogalacturonans but was in the same range for LM5 and LM6 rhamnogalacturonans and xyloglucans. These data show that WI enhancement probably requires arabinogalactan proteins (JIM8) mainly localized on the outer part of the primary wall and WIs. By comparison, NaCl-treated plants exhibited cell wall polysaccharide modifications indicating (1) an increase in unesterified homogalacturonans (JIM5), probably implicated in Na(+) binding and/or polysaccharide network interaction for limiting turgor variations in mesophyll cells; (2) enhancement of the xyloglucan network with an accumulation of fucosylated xyloglucans (CCRC-M1) known to increase the capacity of cellulose binding; and (3) specific recognition of JIM8 arabinogalactan proteins that could participate in both wall enlargement and cohesion by increasing the number of molecular interactions with the other polymers. In conclusion, the cell wall polysaccharide distribution in enlarged WIs might (1) participate in wall resistance to sequestration of Na(+), allowing a better control of hydric homeostasis in mesophyll cells to maintain metabolic activity in source leaves, and (2) maintain tolerance of M. sativa to NaCl.


Subject(s)
Cell Wall/metabolism , Medicago sativa/cytology , Medicago sativa/drug effects , Mucoproteins/metabolism , Plant Leaves/cytology , Polysaccharides/metabolism , Sodium Chloride/pharmacology , Cell Wall/drug effects , Cell Wall/ultrastructure , Epitopes/ultrastructure , Glucans/ultrastructure , Immunohistochemistry , Medicago sativa/metabolism , Medicago sativa/ultrastructure , Pectins/ultrastructure , Plant Leaves/drug effects , Plant Leaves/metabolism , Plant Leaves/ultrastructure , Plant Proteins/metabolism , Xylans/ultrastructure
9.
Eval Rev ; 29(5): 467-89, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16127124

ABSTRACT

This study aims to shed light on the main characteristics of the French system for redistributing wealth to families through tax revenues and social transfers. For the purposes of this exercise, the authors used the MYRIADE microsimulation model, which covers most of the redistribution system, though it is limited to monetary flows such as family benefits, housing allowances, minimum social welfare payments, income tax, and tax on furnished accommodation. The authors used a particular methodology to highlight the way this redistribution works; rather than calculate the difference between each family's disposable income and their gross primary income, they opted to isolate the variation in disposable income that could be attributed to the youngest member of each family where there is at least one child under the age of 25. The average increase in disposable income that this child contributes to his or her family amounts to in200 per month.


Subject(s)
Computer Simulation , Family Characteristics , Income , Public Assistance , Female , France , Humans , Income Tax/statistics & numerical data , Male , Models, Statistical , Public Assistance/statistics & numerical data , Social Justice/statistics & numerical data
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