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1.
Plant Dis ; 2024 Jun 11.
Article de Anglais | MEDLINE | ID: mdl-38861470

RÉSUMÉ

Severe typical deep-pitted lesions of Potato Common Scab (PCS) disease were observed in two locations in China, Dingxi, Gansu Province, and Shuozhou, Shaanxi Province, in 2021. Potato farms in Dingxi growing cultivar Huangxin 226 (26 hectares) exhibited a scab disease incidence of 10%, while cultivar Jinshu 15# (4 hectares) in Shuozhou showed a disease incidence of 30% (Fig. 1). During harvest, tubers displaying PCS symptoms were collected for pathogen isolation. To obtain pathogen isolates, surface-sterilized tuber tissue with scab lesions was ground in sterile water, serially diluted, and plated onto ISP5 agar medium plates (Handique et al. 2022). Five pure colonies of Streptomyces isolate were obtained, designated as ZRIMU1503, ZRIMU1502, ZRIMU1320, ZRIMU1321and ZRIMU791. Genomic DNA was extracted and sequenced using Illumina technology. Sequencing data of the 5 isolates were uploaded to NCBI GenBank and annotated (Accession numbers: JBBAYL010000000, JBBAYM010000000, JBBAYN010000000, JBBAYO010000000 and JBBAYP010000000, respectively) using the PGAP pipeline (Tatusova et al. 2016). Average Nucleotide Identity (ANI) values (97.52 %, 97.53 %,97.54 %,97.57 % and 97.52 %, respectively) indicated the identity of the five isolates to the type strain S. brasiliscabiei IBSBF 2867T. Additionally, pairwise comparisons of Digital DNA Hybridization (DDH) value (76.2%, 76.3%, 76.4%, 76.4% and 76.2% respectively) of all the Streptomyces type strains show the highest identity to S. brasiliscabiei IBSBF 2867T. Twelve housekeeping genes (acnA, atpD, dnaN, gap, gyrA, gyrB , infB, mdh, recA, rplB, rpoB, and trpB) were extracted from the genome sequence of the five isolates to construct a multi-locus sequence analysis (MLSA) tree. The evolutionary distance of the five isolates was constructed using MEGAX software (Kumar et al., 1994), along with other Streptomyces strains that are known to cause PCS. The resulting cladogram demonstrated the isolated strains clustered together with S. brasiliscabiei IBSBF 2867T (Fig.2). Koch's postulates were fulfilled by inoculating a perlite potting mix with spore suspensions of each isolate (104 CFU/ml), planting tubers (cv. Favorita), and reproducing PCS symptoms at harvest after three months. Negative control received water treatment. The plants were kept in greenhouse with 12 h of light per day and irrigated regularly. The experiment was repeated twice, once in April 2022 and again in April 2023. On harvest, all five isolates exhibited development of severe symptoms of PCS (Fig.1), while the negative controls had no lesions. The pathogen was reisolated from the lesions and confirmed to be identical to the original isolate by 16S rRNA gene sequences. To our knowledge, this is the first report of S. brasiliscabiei causing PCS in China. S. brasiliscabiei was identified as a new species to cause PCS in Brazil and was identified based on morphology, pathogenicity, and genetic features (Corrêa et al. 2021). Multiple pathogen-causing PCS has been recognized in China and a surge of disease incidence in potato fields has been reported (Handique et al. 2022; Wu et al. 2023). S. brasiliscabiei causes severe symptoms which makes potatoes unmarketable. The disease epidemiology of this pathogen needs to be investigated.

2.
Front Microbiol ; 15: 1362283, 2024.
Article de Anglais | MEDLINE | ID: mdl-38800750

RÉSUMÉ

Potato soft rot caused by Pectobacterium spp. are devastating diseases of potato which cause severe economic losses worldwide. Pectobacterium brasiliense is considered as one of the most virulent species. However, the virulence mechanisms and pathogenicity factors of this strain have not been fully elucidated. Here, through pathogenicity screening, we identified two Pectobacterium brasiliense isolates, SM and DQ, with distinct pathogenicity levels. SM exhibits higher virulence compared to DQ in inducing aerial stem rot, blackleg and tuber soft rot. Our genomic and transcriptomic analyses revealed that SM encodes strain specific genes with regard to plant cell wall degradation and express higher level of genes associated with bacterial motility and secretion systems. Our plate assays verified higher pectinase, cellulase, and protease activities, as well as fast swimming and swarming motility in SM. Importantly, a unique endoglucanase S specific to SM was identified. Expression of this cellulase in DQ greatly enhances its virulence compared to wild type strain. Our study sheds light on possible determinants causing different pathogenicity of Pectobacterium brasiliense species with close evolutionary distance and provides new insight into the direction of genome evolution in response to host variation and environmental stimuli.

3.
Biol Res ; 56(1): 38, 2023 Jul 12.
Article de Anglais | MEDLINE | ID: mdl-37438836

RÉSUMÉ

Since the discovery, lipid droplets (LDs) have been recognized to be sites of cellular energy reserves, providing energy when necessary to sustain cellular life activities. Many studies have reported large numbers of LDs in eggs and early embryos from insects to mammals. The questions of how LDs are formed, what role they play, and what their significance is for embryonic development have been attracting the attention of researchers. Studies in recent years have revealed that in addition to providing energy for embryonic development, LDs in eggs and embryos also function to resist lipotoxicity, resist oxidative stress, inhibit bacterial infection, and provide lipid and membrane components for embryonic development. Removal of LDs from fertilized eggs or early embryos artificially leads to embryonic developmental arrest and defects. This paper reviews recent studies to explain the role and effect mechanisms of LDs in the embryonic development of several species and the genes involved in the regulation. The review contributes to understanding the embryonic development mechanism and provides new insight for the diagnosis and treatment of diseases related to embryonic developmental abnormalities.


Sujet(s)
Développement embryonnaire , Gouttelettes lipidiques , Femelle , Grossesse , Animaux , Stress oxydatif , Mammifères
4.
Clin Transl Oncol ; 25(5): 1315-1331, 2023 May.
Article de Anglais | MEDLINE | ID: mdl-36520384

RÉSUMÉ

BACKGROUND: Lipid metabolism reprogramming plays an important role in cell growth, proliferation, angiogenesis and invasion of cancer. However, the prognostic value of lipid metabolism during gastric cancer (GC) progression and the relationship with the immune microenvironment are still unclear. The aim of this study was to clarify the correlation between lipid metabolism genes and GC immunity. METHOD: We obtained 350 patients from The Cancer Genome Atlas (TCGA) and 355 patients from Gene Expression Omnibus (GEO) databases. Lipid metabolism-related gene datasets were obtained from the Reactome and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Molecular subtypes were obtained by Consensus clustering, and subtype immune status was analyzed using ESTIMATE, TIMER and microenvironmental cell population counter (MCP Counter) algorithm for immune analysis. Functional analyses included the application of Gene Set Enrichment Analysis (GSEA), KEGG, gene ontology (GO), and Protein-Protein Interaction Networks (PPI) to evaluate the molecular mechanisms of different subtypes. Weighted gene co-expression network analysis (WGCNA) was used to identify genes associated with immunity. The LASSO algorithm and multivariate Cox regression analysis were used to construct prognostic risk models. RESULT: Based on the lipid metabolism genes found in GC, patients with GC can be divided into two subgroups with significantly different survival. The subgroup with a better prognosis presented higher immune scores and immune infiltrating cell abundance. 1170 immune-related genes were screened by WGCNA, and further screening by PPI network analysis revealed that PTPRC, CD4, ITGB2 and LCP2 were closely associated with immune cells. Combined with the TIDE score results, it was found that the population with high expression of the above genes might be more sensitive to immunotherapy. In addition, a survival prediction model for GC was developed based on five survival-related lipid metabolism genes, PIAS4, PLA2R1, PRKACA, SLCO1A2 and STARD4. The ROC analysis over time showed that the risk prediction score model had good stability. CONCLUSION: Lipid metabolism gene expression is correlated with the immune microenvironment in GC patients and can accurately predict their prognosis. Studies on lipid metabolism and GC immunity can help to screen the population for immunotherapy benefits.


Sujet(s)
Tumeurs de l'estomac , Humains , Tumeurs de l'estomac/génétique , Métabolisme lipidique/génétique , Algorithmes , Cycle cellulaire , Prolifération cellulaire , Microenvironnement tumoral , Pronostic , Récepteurs à la phospholipase A2
5.
Clin Transl Oncol ; 25(2): 447-459, 2023 Feb.
Article de Anglais | MEDLINE | ID: mdl-36168087

RÉSUMÉ

BACKGROUND: The importance of metabolism-related alterations in the development of gastric cancer (GC) is increasingly recognized. The present study aimed to identify metabolism-related genes to facilitate prognosis of GC patients. METHODS: Gene expression datasets and clinical information of GC patients were downloaded from TCGA and GEO databases. We scored the enrichment of human metabolism-related pathways (n = 86) in GC samples by GSV, constructed prognostic risk models using LASSO algorithm and multivariate Cox regression analysis, combined with clinical information to construct a nomogram, and finally cis score algorithm to analyze the abundance of immune-related cells in different subtypes. We used Weka software to screen for prognosis-related marker genes and finally validated the expression of the selected genes in clinical cancer patient tissues. RESULTS: We identified that two GC metabolism-related signatures were strongly associated with OS and the levels of immune cell infiltration. Moreover, a survival prediction model for GC was established based on six GC metabolism-related genes. Time-dependent ROC analysis showed good stability of the risk prediction scoring model. The model was successfully validated in an independent ACRG cohort, and the expression trends of key genes were also verified in the GC tissues of patients. DLX1, LTBP2, FGFR1 and MMP2 were highly expressed in the cluster with poorer prognosis while SLC13A2 and SLCO1B3 were highly expressed in the cluster with better prognosis. CONCLUSIONS: We identified a risk predictive score model based on six metabolism-related genes related to survival, which may serve as prognostic indicators and potential therapeutic targets for GC.


Sujet(s)
Tumeurs de l'estomac , Humains , Algorithmes , Protéines de liaison au TGF-bêta latent , Nomogrammes , Oncogènes , Pronostic , Tumeurs de l'estomac/diagnostic , Tumeurs de l'estomac/génétique
6.
Clin Nutr ; 37(2): 728-738, 2018 04.
Article de Anglais | MEDLINE | ID: mdl-28483328

RÉSUMÉ

BACKGROUND & AIMS: The aim of the study was to evaluate the applicability of the ESPEN 16-category clinical classification of chronic intestinal failure, based on patients' intravenous supplementation (IVS) requirements for energy and fluids, and to evaluate factors associated with those requirements. METHODS: ESPEN members were invited to participate through ESPEN Council representatives. Participating centers enrolled adult patients requiring home parenteral nutrition for chronic intestinal failure on March 1st 2015. The following patient data were recorded though a structured database: sex, age, body weight and height, intestinal failure mechanism, underlying disease, IVS volume and energy need. RESULTS: Sixty-five centers from 22 countries enrolled 2919 patients with benign disease. One half of the patients were distributed in 3 categories of the ESPEN clinical classification. 9% of patients required only fluid and electrolyte supplementation. IVS requirement varied considerably according to the pathophysiological mechanism of intestinal failure. Notably, IVS volume requirement represented loss of intestinal function better than IVS energy requirement. A simplified 8 category classification of chronic intestinal failure was devised, based on two types of IVS (either fluid and electrolyte alone or parenteral nutrition admixture containing energy) and four categories of volume. CONCLUSIONS: Patients' IVS requirements varied widely, supporting the need for a tool to homogenize patient categorization. This study has devised a novel, simplified eight category IVS classification for chronic intestinal failure that will prove useful in both the clinical and research setting when applied together with the underlying pathophysiological mechanism of the patient's intestinal failure.


Sujet(s)
Maladies intestinales/diétothérapie , Maladies intestinales/anatomopathologie , Nutrition parentérale à domicile/méthodes , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Australasie , Maladie chronique , Études transversales , Europe , Femelle , Humains , Intestins/anatomopathologie , Israël , Mâle , Adulte d'âge moyen , Amérique du Sud , États-Unis , Jeune adulte
7.
J ECT ; 32(1): 17-9, 2016 Mar.
Article de Anglais | MEDLINE | ID: mdl-26075692

RÉSUMÉ

OBJECTIVES: Electroconvulsive therapy (ECT) has dramatically reduced musculoskeletal complications when carried out with muscle relaxants under general anesthesia. However, seizure quality can be affected by the depth of anesthesia and choice of anesthetic agent. The purpose of this study was to describe a general anesthetic technique for ECT by using laryngeal mask, bispectral index (BIS), and muscle relaxant monitoring. METHODS: Twenty-one patients, between ages 18 and 70 years (American Society of Anesthesiologists physical status I-III), who underwent a total of 89 sessions of ECT were examined in a retrospective study. Anesthesia was induced by use of propofol (1.0 mg/kg) followed by cisatracurium (0.2 mg/kg). The BIS, train-of-four, and end-tidal carbon dioxide were all monitored continuously. A laryngeal mask airway was used to maintain and protect the airway during the procedure. Electroconvulsive therapy stimuli were applied bilaterally when the train-of-four was assessed as being zero and BIS scores were 70. All patients then received 5 µg sufentanil and 2 mg midazolam, while titrated to maintain the BIS value at 40 to 50, before the muscle relaxation exhibited complete recovery. RESULTS: The mean duration of treatment process takes approximately 82.5 minutes. Mean (SD) seizure length was 58.8 (28.3) seconds, with 4.5% incidence of restimulation per treatment. Incidence of awareness was 0%. No patients exhibited delirium, nausea, vomiting, or myalgia in the postseizure phase. CONCLUSIONS: Bispectral index monitoring of the depth of anesthesia may have improved seizure quality, and awareness did not occur.


Sujet(s)
Anesthésie générale , Atracurium/analogues et dérivés , Moniteurs d'évaluation de la conscience , Électroconvulsivothérapie/méthodes , Masques laryngés , Curarisants non dépolarisants , Adolescent , Adulte , Sujet âgé , Anesthésie générale/effets indésirables , Atracurium/effets indésirables , Dioxyde de carbone/sang , Électroconvulsivothérapie/effets indésirables , Femelle , Humains , Conscience peropératoire , Mâle , Adulte d'âge moyen , Curarisants non dépolarisants/effets indésirables , Sécurité des patients , Études rétrospectives , Crises épileptiques/physiopathologie , Jeune adulte
8.
Structure ; 18(11): 1471-82, 2010 Nov 10.
Article de Anglais | MEDLINE | ID: mdl-21070946

RÉSUMÉ

The major cAMP receptors in eukaryotes are the regulatory (R) subunits of PKA, an allosteric enzyme conserved in fungi through mammals. While mammals have four R-subunit genes, Saccharomyces cerevisiae has only one, Bcy1. To achieve a molecular understanding of PKA activation in yeast and to explore the evolution of cyclic-nucleotide binding (CNB) domains, we solved the structure of cAMP-bound Bcy1(168-416). Surprisingly, the relative orientation of the two CNB domains in Bcy1 is very different from mammalian R-subunits. This quaternary structure is defined primarily by a fungi-specific sequence in the hinge between the αB/αC helices of the CNB-A domain. The unique interface between the two CNB domains in Bcy1 defines the allosteric mechanism for cooperative activation of PKA by cAMP. Some interface motifs are isoform-specific while others, although conserved, play surprisingly different roles in each R-subunit. Phylogenetic analysis shows that structural differences in Bcy1 are shared by fungi of the subphylum Saccharomycotina.


Sujet(s)
Cyclic AMP-Dependent Protein Kinases/composition chimique , Évolution moléculaire , Modèles moléculaires , Conformation des protéines , Sous-unités de protéines/composition chimique , Séquences d'acides nucléiques régulatrices/génétique , Saccharomyces cerevisiae/enzymologie , Transduction du signal/physiologie , Analyse de regroupements , Cristallographie , Cyclic AMP-Dependent Protein Kinases/métabolisme , Simulation de dynamique moléculaire , Phylogenèse , Sous-unités de protéines/métabolisme , Saccharomyces cerevisiae/physiologie , Transduction du signal/génétique
9.
Genet. mol. biol ; Genet. mol. biol;31(3): 711-716, 2008. graf, tab
Article de Anglais | LILACS | ID: lil-490060

RÉSUMÉ

The genetic relationships between amylose content (AC) and appearance quality traits of indica rice (Oryza sativa L.) were investigated using conditional analysis and unconditional analysis in present experiment. The results from the unconditional analysis indicated that AC of rice positively correlated with brown rice (BR, i.e., dehulled but unmilled rice) length (BRL), width (BRW) and thickness (BRT), but was negatively correlated with the ratio of length to width (RLW). The conditional analysis showed that weight of brown rice (WBR) negatively affected the genetic relationships between AC and the appearance quality traits of rice except between AC and BRW, while the genetic relationships between AC and most appearance quality traits were negatively affected by protein content (PC). However, these influences were not apparent due to the impact of WBR or PC on the most covariance components of the different genetic systems between AC and the appearance quality traits. The conditional analysis showed that it was possible to improve AC while significantly reduce BRL and BRT under maintaining WBR. Furthermore, AC could be improved when BRL was reduced under maintaining PC, but BRW and BRT could be significantly increased.

10.
Inorg Chem ; 45(1): 189-95, 2006 Jan 09.
Article de Anglais | MEDLINE | ID: mdl-16390055

RÉSUMÉ

The manganese-oxo "cubane" core complex Mn(4)O(4)L(1)(6) (1, L(1) = Ph(2)PO(2-)), a partial model of the photosynthetic water oxidation site, was shown previously to undergo photodissociation in the gas phase by releasing one phosphinate anion, an O(2) molecule, and the intact butterfly core cation (Mn(4)O(2)L(1)(5+)). Herein, we investigate the photochemistry and electronic structure of a series of manganese-oxo cubane complexes: [Mn(4)O(4)L(2)(6)] (2), 1(+)(ClO(4-)), 2(+)(ClO(4-)), and Mn(4)O(3)(OH)L(1)(6) (1H). We report the atomic structure of [Mn(4)O(4)L(2)(6)](ClO(4)), 2(+)(ClO(4-)) [L(2) = (4-MeOPh)(2)PO(2-)]. UV photoexcitation of a charge-transfer band dissociates one phosphinate, two core oxygen atoms, and the Mn(4)O(2)L(5)(+) butterfly as the dominant (or exclusive) photoreaction of all cubane derivatives in the gas phase, with relative yields: 1H >> 2 > 1 > 2(+) > 1(+). The photodissociation yield increases upon (1) reducing the core oxidation state by hydrogenation of a corner oxo (1H), (2) increasing the electron donation from the phosphinate ligand (L(2)), and (3) reducing the net charge from +1 to 0. The experimental Mn-O bond lengths and Mn-O bond strengths and the calculated ligand binding energy explain these trends in terms of weaker binding of phosphinate L(2) versus L(1) by 14.7 kcal/mol and stronger Mn-(mu(3)-O)(core) bonds in the oxidized complexes 2(+) and 1(+) versus 2 and 1. The calculated electronic structure accounts for these trends in terms of the binding energy and antibonding Mn-O(core) and Mn-O'(ligand) character of the degenerate highest occupied molecular orbital (HOMO), including (1) energetic destabilization of the HOMO of 2 relative to 1 by 0.75 eV and (2) depopulation of the antibonding HOMO and increased ionic binding in 1(+) and 2(+) versus 1 and 2.


Sujet(s)
Manganèse/composition chimique , Composés organométalliques/composition chimique , Oxygène/composition chimique , Simulation numérique , Électrons , Manganèse/effets des radiations , Modèles chimiques , Conformation moléculaire , Composés organométalliques/effets des radiations , Oxydoréduction , Oxygène/effets des radiations , Photochimie , Stéréoisomérie , Rayons ultraviolets
11.
Genet. mol. biol ; Genet. mol. biol;29(3): 533-538, 2006. graf
Article de Anglais | LILACS | ID: lil-450294

RÉSUMÉ

Analysis of genetic main effects and genotype x environment (GE) interaction effects on the oil content of oilseed rape (Brassica napus L.) was conducted by using a genetic model for the quantitative traits of seeds in diploid plants. The experiments were carried out over two years with 8 parents and a diallel mating design, which produced F1 and F2 generations. We found that the oil content of rape was simultaneously controlled by embryo genetic effect, cytoplasmic effects and maternal genetic effect as well as GE interaction effects, with the cytoplasmic and maternal effects playing the main role. The results indicate that selection of maternal plants for high oil content would be more efficient than selection based on single seeds. Since the GE interaction effects accounted for 73.69 percent of the total genetic effects and were more important than the genetic main effects it seems that selection might be influenced by environmental conditions. The estimate of narrow-sense heritability for oil content was 73.52 percent with the interaction heritability being larger than the general heritability, indicating that the early generations can be used for selection for high oil content. The prediction of genetic effects suggested that the parent cultivars Youcai 601 and Gaoyou 605 were better than the other cultivars for increasing oil content during the breeding of B. napus. The implications for the quantitative trait loci mapping of seed traits interfered by these three genetic systems is also discussed.


Sujet(s)
Brassica napus/génétique , Hérédité , Exposition environnementale , Locus de caractère quantitatif , Sélection génétique
12.
Lab Chip ; 5(12): 1344-7, 2005 Dec.
Article de Anglais | MEDLINE | ID: mdl-16286963

RÉSUMÉ

In this communication, a novel micro flow sensor based on two closely spaced amperometric oxygen sensors is proposed and implemented. The simulation results show that the ratio of the responses of these two oxygen sensors is determined by flow rates in the micro-channel. The sensor has been implemented using a micro fabrication technique. The measurement results demonstrate that the technique is able to detect flow rates in the flow range of several microliters per minute when the distance between the working electrodes of two oxygen sensors is 10 microm and the cross-section of the micro-channel is 100 microm x 100 microm. The advantage of the proposed flow sensor is that no additional tracers have to be added or produced during the flow measurement. Information on dissolved oxygen concentration in the liquid is not required either.


Sujet(s)
Techniques de biocapteur/instrumentation , Analyse par injection en flux continu/instrumentation , Microfluidique/instrumentation , Oxygène/analyse , Oxygène/composition chimique , Transducteurs , Techniques de biocapteur/méthodes , Conception assistée par ordinateur , Conception d'appareillage , Analyse de panne d'appareillage , Analyse par injection en flux continu/méthodes , Microfluidique/méthodes , Miniaturisation
13.
Inorg Chem ; 43(19): 5795-7, 2004 Sep 20.
Article de Anglais | MEDLINE | ID: mdl-15360226

RÉSUMÉ

A new member of the Mn-oxo cubane core complex family [Mn2III,2IV4O4L6] (1), where L = (p-MeOPh)2PO2-, has been synthesized and characterized. Compound 1 possesses structurally inequivalent MnIII and MnIV with clear valence electron localization in the crystal phase, quite unlike the structurally equivalent sites, tetrahedral core symmetry, and delocalized valence of its analogue where L = Ph2PO2-. Compound 1 exhibits appreciable positive shifts (0.1-0.3 V) of both the oxidation and reduction electrochemical potentials, attributable to the remote electron donating p-MeO groups. Reduction of 1 by methanol yields a novel core complex [MnIII4O2(OMe)2(MeOH)[(p-MeOPh)2PO2]6] (2). Each MnIII of 2 is tetragonally distorted due to the Jahn-Teller effect with elongated Mn-O bonds that are directed at the two micro3-MeO bridges and neither of the two micro3-oxos. These electronically driven distortions provide a structural rationale for the greater basicity of the former sites and explain why 2 of the 4 corner oxos are preferentially reduced to water molecules.


Sujet(s)
Manganèse/composition chimique , Composés organométalliques/composition chimique , Composés organométalliques/synthèse chimique , Spectroscopie par résonance magnétique , Modèles moléculaires , Conformation moléculaire , Oxydoréduction , Thermodynamique , Eau
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