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1.
Bol. latinoam. Caribe plantas med. aromát ; 23(2): 180-198, mar. 2024. ilus, tab, graf
Article Dans Anglais | LILACS | ID: biblio-1538281

Résumé

India's commercial advancement and development depend heavily on agriculture. A common fruit grown in tropical settings is citrus. A professional judgment is required while analyzing an illness because different diseases have slight variati ons in their symptoms. In order to recognize and classify diseases in citrus fruits and leaves, a customized CNN - based approach that links CNN with LSTM was developed in this research. By using a CNN - based method, it is possible to automatically differenti ate from healthier fruits and leaves and those that have diseases such fruit blight, fruit greening, fruit scab, and melanoses. In terms of performance, the proposed approach achieves 96% accuracy, 98% sensitivity, 96% Recall, and an F1 - score of 92% for ci trus fruit and leave identification and classification and the proposed method was compared with KNN, SVM, and CNN and concluded that the proposed CNN - based model is more accurate and effective at identifying illnesses in citrus fruits and leaves.


El avance y desarrollo comercial de India dependen en gran medida de la agricultura. Un tipo de fruta comunmente cultivada en en tornos tropicales es el cítrico. Se requiere un juicio profesional al analizar una enfermedad porque diferentes enfermedades tienen ligeras variaciones en sus síntomas. Para reconocer y clasificar enfermedades en frutas y hojas de cítricos, se desarrolló e n esta investigación un enfoque personalizado basado en CNN que vincula CNN con LSTM. Al utilizar un método basado en CNN, es posible diferenciar automáticamente entre frutas y hojas más saludables y aquellas que tienen enfermedades como la plaga de frutas , el verdor de frutas, la sarna de frutas y las melanosis. En términos de desempeño, el enfoque propuesto alcanza una precisión del 96%, una sensibilidad del 98%, una recuperación del 96% y una puntuación F1 del 92% para la identificación y clasificación d e frutas y hojas de cítricos, y el método propuesto se comparó con KNN, SVM y CNN y se concluyó que el modelo basado en CNN propuesto es más preciso y efectivo para identificar enfermedades en frutas y hojas de cítricos.


Sujets)
Citrus/classification , Citrus/parasitologie , , Feuilles de plante/classification , Feuilles de plante/parasitologie , Intelligence artificielle/tendances , Fruit/classification , Fruit/croissance et développement
2.
Acta Pharmaceutica Sinica ; (12): 1965-1975, 2021.
Article Dans Chinois | WPRIM | ID: wpr-887020

Résumé

Cephalosporins are widely used in the treatment of infectious diseases. The structural differences in cephalosporin drugs mainly lie in the C-7 amino side chain and the C-3 substituent. In this study, twenty-five haloacylated cephalosporins of five series were designed by using a strategy of introducing simple substituents at the C-7 amino group in four cephalosporin parent nucleus with different C-3 substituents and efficiently synthesized under optimized conditions. Their activities against human pathogenic bacteria, Pichia pastoris, citrus canker and citrus pathogenic fungi were evaluated. The results showed that most of the molecules had activity against human pathogenic bacteria, of which seven compounds including TM1f had stronger or equivalent inhibitory activities against eight human pathogens than the marketed drugs cefalotin, cefoxitin sodium and ceftizoxime sodium. The inhibitory activity of TM1s against Alternaria alternate Al.6 was stronger than that of cephalosporins and comparable to that of the positive control prochloraz. TM1f and TM1s are worthy of further study.

3.
Biosci. j. (Online) ; 36(6): 2020-2028, 01-11-2020. ilus, tab, graf
Article Dans Anglais | LILACS | ID: biblio-1148292

Résumé

Pseudomonas syringae pv. actinidiae is a bacterial pathogen of kiwifruit. Based on the results of the pathogenicity assay, we sequenced the strain Pseudomonas syringae (Psa3) P155 which possesses a series of virulence and resistance genes, CRISPR candidate elements, prophage related sequences, methylation modifications, genomic islands as well as one plasmid. Most importantly, the copper resistance genes copA, copB, copC, copD, and copZ as well as aminoglycoside resistance gene ksgA were identified in strain P155, which would pose a threat to kiwifruit production. The complete sequence we reported here will provide valuable information for a better understanding of the genetic structure and pathogenic characteristics of the genome of P155.


Pseudomonas syringae pv. actinidiae agente causal do cancro bacteriano do kiwi. Com base nos resultados do teste de patogenicidade, foi sequenciado um isolado de Pseudomonas syringae (Psa3) P155, que abriga a uma série de genes de virulência e resistência, elementos candidatos CRISPR, sequências relacionadas a profagos, modificações na metilação, ilhas genômicas, e também um plasmídeo. O mais importante foram os genes de resistência ao cobre, copA, copB, copC, copD e copZ, bem como, o gene de resistência aminoglicosídea ksgA identificados na estirpe P155, os quais representariam uma ameaça à produção de kiwi. A sequência completa relatada fornecerá informações valiosas para uma melhor compreensão da estrutura genética e as características patogênicas do genoma de P155.


Sujets)
Virulence , Actinidia , Pseudomonas syringae , Séquençage du génome entier
4.
J Genet ; 2020 Jan; 99: 1-13
Article | IMSEAR | ID: sea-215554

Résumé

Class III peroxidase (CIII prx) is a plant-specific multigene family that regulates the physiological and stress responses. This research aimed to exhaustively annotate and analyse the CIII prx family in sweet orange and to explore the regulated expression profiles by Xanthomonas citri subsp. citri (Xcc) and plant hormones. We further assessed the relationship between CIII prxs and citrus bacterial canker. The phylogeny, gene structure, conserved motifs, gene duplications and microsynteny of the CIII prx family were analysed. Expression profiles of specific CsPrxs induced by Xanthomonas citri subsp. citri and plant hormones were detected by quantitative reverse transcription-polymerase chain reaction. Subcellular localization was analysed through transient expression assessments. A total of 72 CIII prx members were identified from the genomes of sweet orange. In all chromosomes of sweet orange, the CsPrxs could be detected except in chromosome 8. In addition, three segmental duplications, four tandem duplications and 11 whole-genome duplications occurred among the CsPrxs, contributing to the family size expansion. From the Ka/Ks ratios, 15 of 18 duplicated CsPrxs pairs have experienced purifying selection process. A total of 15 conserved motifs were detected in CsPrxs, four of which were detected in all complete CsPrxs. A total of 12 expressed genes were identified from the EST database. The expression trends of 12 CsPrxs were differently expressed at different stages of infection by Xcc, five of which were potential candidate genes involved in Xcc resistance. These genes could be induced by salicylic acid and methyl jasmonate, and were extracellular proteins. These results further support our understanding of CIII prxs in citrus, particularly in citrus bacterial canker studies

5.
Ciênc. rural (Online) ; 50(10): e20200198, 2020. tab, graf
Article Dans Anglais | LILACS-Express | LILACS | ID: biblio-1133189

Résumé

ABSTRACT: The persimmon tree is known for its rusticity and productivity and was first introduced to Brazil in the late 19th century. However, anthracnose disease is causing immature fruit drop and severe disease symptoms in persimmon fruit, shoots, flowers, and twigs. The causal agent was first described as the fungal species, Colletotrichum horii, which was first confirmed using only the ITS region. In this study, we compared the aggressiveness of 13 isolates of Colletotrichum spp. obtained from fruit and shoots of persimmon grown in the Metropolitan Region of Curitiba, Paraná State, Brazil. A multilocus molecular analysis was carried out based on ITS, GPDH, and EF genes, and we confirmed that the isolates were confirmed as C. horii. All isolates were pathogenic for unwounded and wounded persimmon fruit but differed in aggressiveness. Only one isolate was non-pathogenic when inoculated into unwounded persimmon shoots. Most isolates caused cankers and shoot death whether shoots were wounded or unwounded. In this study, we emphasized the importance of shoots as a source of primary inoculum. In future studies, it will be critical to further elucidate the epidemiological basis of anthracnose disease by conducting field studies to establish a more effective strategy for disease control.


RESUMO: O caquizeiro foi introduzido no Brasil no final do século XIX. Esta planta é conhecida por sua rusticidade e produtividade. No entanto, a doença antracnose está causando queda e sintomas em frutos imaturos, ramos, flores e galhos no campo. O agente causal foi descrito inicialmente como Colletotrichum hori (confirmado usando apenas a região ITS) causando cancro de galho e sintomas de folhas. Neste estudo, comparamos a agressividade em caqui utilizando uma coleção de 13 isolados de Colletotrichum spp. obtidos de frutos e ramos de caqui da região metropolitana de Curitiba, Paraná, Brasil. Uma análise molecular multilocus foi realizada com base nos genes ITS, GPDH e EF, e os isolados foram confirmados como pertencentes a C. horii. Todos os isolados foram patogênicos em frutos não feridos e feridos, mas diferiram na agressividade. Apenas um isolado não foi patogênico quando inoculado sem ferimento em ramos. A maioria dos isolados foi capaz de causar cancro e morte de ramo, independentemente do ferimento. Neste estudo, enfatizamos a importância das novas brotações como fonte de inóculo primário. Para um próximo estudo, ainda é necessário ampliar as bases epidemiológicas com estudos em campo para estabelecer uma correta estratégia de controle desta doença.

6.
Article Dans Anglais | IMSEAR | ID: sea-181887

Résumé

Recurrent aphthous stomatitis (RAS) is one of the common clinical oral diseases that produces painful ulcerations in the oral cavity .It is also called canker sore or mouth ulcer. Although , the clinical features and characteristics of this disease are easily defined , the etiology and the pathophysiology remain unclear . So as a result, the available treatments still remaining unsatisfactory with the ability to reduce the severity , healing time and the frequency of recurrence of ulceration with no permanent and definitive treatment. The healing time ranges usually from seven to fourteen days. This review discusses the different treatment modalities and updates that are available to the moment and according to the severity of the ulceration, the clinician can decide to go with topical , physical or systemic treatments which give the clinician broad and detailed picture to deal with RAS in an appropriate way.

7.
Braz. j. microbiol ; 47(2): 518-526, Apr.-June 2016. graf
Article Dans Anglais | LILACS | ID: lil-780835

Résumé

Abstract Citrus canker, caused by the Gram-negative bacterium Xanthomonas citri subsp. citri (Xac), is one of the most devastating diseases to affect citrus crops. There is no treatment for citrus canker; effective control against the spread of Xac is usually achieved by the elimination of affected plants along with that of asymptomatic neighbors. An in depth understanding of the pathogen is the keystone for understanding of the disease; to this effect we are committed to the development of strategies to ease the study of Xac. Genome sequencing and annotation of Xac revealed that ∼37% of the genome is composed of hypothetical ORFs. To start a systematic characterization of novel factors encoded by Xac, we constructed integrative-vectors for protein expression specific to this bacterium. The vectors allow for the production of TAP-tagged proteins in Xac under the regulation of the xylose promoter. In this study, we show that a TAP-expression vector, integrated into the amy locus of Xac, does not compromise its virulence. Furthermore, our results also demonstrate that the polypeptide TAP can be overproduced in Xac and purified from the soluble phase of cell extracts. Our results substantiate the use of our vectors for protein expression in Xac thus contributing a novel tool for the characterization of proteins and protein complexes generated by this bacterium in vivo.


Sujets)
Protéines bactériennes/génétique , Xanthomonas/génétique , Protéines de fusion recombinantes/génétique , Maladies des plantes/microbiologie , Protéines bactériennes/isolement et purification , Protéines bactériennes/métabolisme , Xanthomonas/métabolisme , Xanthomonas/composition chimique , Protéines de fusion recombinantes/isolement et purification , Protéines de fusion recombinantes/métabolisme , Cadres ouverts de lecture , Citrus/microbiologie , Vecteurs génétiques/génétique , Vecteurs génétiques/métabolisme
8.
Biosci. j. (Online) ; 32(2): 361-370, mar./abr. 2016. tab, ilus, graf
Article Dans Anglais | LILACS | ID: biblio-965424

Résumé

An experiment was conducted at Tuber Crops Research Centre, BARI, Bogra during 2008-2009 to evaluate the organic amendment for controlling the stem canker and black scurf of potato. The different kinds of organic amendments were: T1 =Poultry refuse (PR) at 4 t ha-1, T2 =PR at 5 t ha-1, T3 =PR at 6 t ha-1, T4 =Mustard oil cake (MOC) at 300kg ha-1, T5 =MOC at 500kg ha-1, T6 =Neem oil cake (NOC) at 300kg ha-1, T7 =NOC at 500kg ha-1, T8 =Sawdust burning and T9 = Control. The experiment was laid out in a randomized complete block design (RCBD) with four replications. The organic amendment significantly influenced the disease incidence, yield attributes and yield of potato. The lowest disease incidence (17.5%) and per cent disease index (9.99) were found in T3 (poultry waste at 6 t ha-1). The minimum russet, deformed and Sclerotia infected tubers were also recorded in poultry waste at 6 t ha-1. The highest healthy tubers and tuber yield were found in the same treatment. Therefore, poultry manure 6 t ha-1 along with recommended dose of chemical fertilizer can be recommended to produce healthy tubers and maximum tuber yield of potato.


O experimento foi conduzido no (Centro de Pesquisa em Tubérculos ) Tuber Crops Research Centre, Bari, Bogra durante 2008-2009 para avaliar a alteração orgânica e controlar o cancro da haste e Black Scurf da batata. Os diferentes tipos de alterações orgânicas foram: T1 = Poultry recusar (PR) a 4 t ha-1, T2 = PR a 5 t ha-1, T3 = PR em 6 t ha-1, T4 = bolo de óleo de mostarda (MOC) em 300 kg ha-1, T5 = MOC em 500 kg ha-1, T6 = bolo de óleo de Neem (NOC) em 300 kg ha-1, T7 = NOC em 500 kg ha-1, T8 = queima de serragem e T9 = Controle. O delineamento experimental foi em blocos casualizados (RCBD) com quatro repetições. A alteração orgânica influenciou significativamente a incidência da doença, os atributos de rendimento e produtividade da batata. A menor incidência da doença (17,5%) por cento do índice de doença (9,99) foram encontrados em T3 (resíduos de aves a 6 t ha-1). O russet mínimo, deformado e Sclerotia tubérculos infectados também foram registrados em resíduos de aves a 6 t ha-1. O rendimento mais elevado tubérculos saudáveis e tubérculos foram encontrados no mesmo tratamento. Portanto, aviário 6 t ha-1, juntamente com a dose recomendada de fertilizante químico pode ser recomendado para a produção de tubérculos saudáveis e rendimento máximo dos tubérculos de batata.


Sujets)
Rhizoctonia , Sol , Solanum tuberosum
9.
Mycobiology ; : 366-370, 2015.
Article Dans Anglais | WPRIM | ID: wpr-729602

Résumé

Acanthopanax divaricatus, a member of the Araliaceae family, has been used as an invigorant in traditional Korean medicine. During disease monitoring, a stem with small, irregular, brown lesions was sampled at a farm in Cheonan in 2011. The symptoms seen were sunken cankers and reddish-brown needles on the infected twig. The isolated fungal colonies were whitish, having crenated edges and aerial mycelium on the surface, and with black gregarious fruiting bodies. The reverse plate was creamy white. Conidia were 17~22 x 3.5~4.2 microm, fusiform, 4-septate, and straight to slightly curved. The nucleotide sequence of the partial translation elongation factor 1 alpha gene of the fungal isolate, shares 99% sequence identity with that of known Pestalotiopsis ellipsospora. Based on the results of the morphological and molecular analyses, the fungal isolate was identified as P. ellipsospora. In Korea, this is the first report of canker on A. divaricatus.


Sujets)
Humains , Eleutherococcus , Araliaceae , Séquence nucléotidique , Fruit , Corée , Mycelium , Aiguilles , Facteur-1 d'élongation de la chaîne peptidique , Spores fongiques
10.
Bol. micol. (Valparaiso En linea) ; 29(1): 18-27, jul. 2014. ilus, tab
Article Dans Espagnol | LILACS | ID: lil-716831

Résumé

Desde el punto de vista estrictamente micológico, se ha discutido por décadas la relación de Cylindrocarpon cylindroides como anamorfo de Neonectria fuckeliana, lo que entre otras consecuencias, ha incidido en la controversial ubicación taxonómica de este teleomorfo. Se añade a esto que en patología forestal se ha brindado poca atención a la presencia de C. cylindroides dentro del ciclo de la enfermedad causada por Neonectria fuckeliana en coníferas, razón por la cual los estudios específicos respecto de este anamorfo han sido también muy escasos. El presente trabajo tuvo como objetivo verificar la relación entre C. cylindroides y Neonectria fuckeliana, asociados a cancros en troncos de Pinus radiata en Chile, mediante el análisis de las características macro y micromorfológicas que ellos manifiestan en cultivos in vitro, además de análisis de tipo molecular. Se pudo constatar que ambos agentes dieron origen a colonias con idénticas características macro y micromorfológicas, destacando entre éstas la producción de abundantes conodióforos y microconidios del tipo Acremonium, el cual ya ha sido señalado en anteriores estudios como estado anamorfo de Neonectria fuckeliana. El que este mismo estado asexual del tipo Acremonium haya sido la manifestación in vitro tanto de C. cylindroides como de Neonectria fuckeliana, permitió confirmar la relación existente entre estos dos agentes en estudio, la que también fue ratificada mediante los análisis moleculares realizados.


From the point of view strictly mycological has been discussed for decades the relationship of Cylindrocarpon cylindroides as anamorph of Neonectria fuckeliana, which among other consequences, has influenced the controversial taxonomic status of this teleomorph. Add to this that in forest pathology has given little attention to the presence of C. cylindroides within the cycle of the disease caused by Neonectria fuckeliana on conifers, why specific studies regarding this anamorph have been very few. This study aimed to verify the relationship between C. cylindroides and Neonectria fuckeliana associated with cankers on trunks of Pinus radiata in Chile, by analyzing the macro and micromorphological characteristics they manifest in cultures in vitro, further analysis type molecular. It was found that both agents gave rise to colonies with identical macro and micromorphological characteristics, highlighting among them the production of abundant microconidia and conidiophores of Acremonium type, which has already been noted in previous studies as anamorph state of Neonectria fuckeliana. The asexual state that this same type of Acremonium has been the in vitro demons-tration of both C. cylindroides as Neonectria fuckeliana, allowed us to confirm the relationship between these two agents in the study, which was also ratified by the molecular analyzes performed.


Sujets)
Acremonium/croissance et développement , Tracheobionta/microbiologie , Écorce/microbiologie , Spores fongiques/isolement et purification , Spores fongiques/classification , Spores fongiques/croissance et développement , Spores fongiques/pathogénicité , Corps fructifères de champignon , Interactions hôte-pathogène , Pinus/microbiologie , Chili , Flux Laminaire
11.
Biosci. j. (Online) ; 30(4): 1108-1117, july/aug. 2014. ilus, tab
Article Dans Anglais | LILACS | ID: biblio-967417

Résumé

Black scurf and stem canker disease cause by the fungal pathogen of Rhizoctonia solani and it is an economical important disease of potatoes in Bangladesh and throughout the world. This study evaluated the black scurf and stem canker disease development in potato and antagonistic activity of Trichoderma spp. against R. solani. The artificial infections were carried out using the inoculums of R. solani. The treatments (%inoculum) were: T1 (0% inoculum), T2 (5% inoculum), T3 (10% inoculum), T4 (20% inoculum), T5 (50% inoculum), and T6 (100% inoculum). The infection of stem canker and black scurf on progeny tubers increased with increase in inoculum levels. The highest disease incidence and severity was found in T6 (100% inocula). T6 showed the maximum black scurf infected tubers (russet, deformed and sclerotia). The lowest germination percentage, plant height and tuber yield were also obtained in the same treatment (100% inocula). Trichoderma spp reduced the growth of R. solani and the highest growth suppression was noted in isolate TM12. According to antagonistic activity, Trichoderma spp. reduced the growth of R. solani but was not able to stop the pathogen development. This finding showed management of this disease or R. solani invasion requires an integrated approach compared to Trichoderma single approach.


A rizoctoniose ou crosta negra causada por Rhizoctonia solani é a mais importante doença nos campos de batata em Bangladesh, bem como em várias regiões do mundo. Este trabalho avaliou o potencial do biocontrole com Trichoderma spp. e sua ação antagonista contra R. solani em batateira. Realizou-se as avaliações do potencial antagonosta usando inoculação artificial de R. solani. Os tratamentos (% de inóculo) foram: T1 (0% de inóculo), T2 (5% ), T3 (10%), T4 (20%), T5 (50%) , e T6 (100% de inóculo). A infecção de rizoctoniose na haste e crosta negra nos tubérculos aumentou proporcionalmente com o aumento do nível de inóculo. A maior incidência e severidade da doença ocorreu no tratamento 6 (100 % de inóculo), o qual apresentou maior quantidade de tubérculos infectados e deformados com escleródios em sua superfície. A menor porcentagem de germinação e produção de tubérculos também foi encontrada no tratamento 6, o qual também apresentou menor altura de planta. Trichoderma spp reduziu o crescimento de R. solani e a maior atividade de supressão do crescimento foi encontrada pelo isolado TM12. Foi detectada a atividade antagonista de Trichoderma spp. em reduzir o crescimento de R. solani, mas este não inibiu o crescimento total do patógeno. Conclui-se que o manejo da rizoctoniose da batateira por colonização de R. solani necessita táticas de manejo integrado em detrimento do uso isolado do manejo ou biocontrole com Trichoderma spp.


Sujets)
Rhizoctonia , Trichoderma , Solanum tuberosum
12.
Bol. micol. (Valparaiso En linea) ; 28(2): 53-57, dic. 2013. ilus
Article Dans Espagnol | LILACS | ID: lil-708087

Résumé

El presente trabajo tuvo por finalidad reportar y analizar la presencia de estructuras fungosas (esporodoquios) sobre cancros causados por Neonectria fuckeliana en árboles de Pinus radiata en Chile. Las muestras fueron colectadas en las Regiones de La Araucanía y de Los Ríos y fueron analizadas en el laboratorio. Los resultados de los análisis morfológicos y taxonómicos permitieron concluir que los esporodoquios hallados correspondían al sinanamorfo de Neonectria fuckeliana (forma cylindrocarpon cylindroides var tenue), siendo el primer reporte en el país. Estos antecedentes contribuyen al conocimiento y comprensión del ciclo patológico y epidemiológico de Neonectria fuckeliana en plantaciones de Pinus radiata.


The present work was aimed at reporting and analyzing the presence of fungal structures (sporodochia) present on cankers caused by Neonectria fuckeliana in Pinus radiata trees in Chile. The samples were collected in the regions of La Araucanía and Los Ríos and analyzed in the laboratory. The results of morphological and taxonomic analysis led to the conclusion that thesporodochia found corresponded to sinanamorph of Neonectria fuckeliana (cylindrocarpon cylindroides var. tenue morph), the first report in the country. This work contribute to understanding and comprehension of the disease cycle and epidemiology of Neonectria fuckeliana on plantations of Pinus radiata.


Sujets)
Écorce/microbiologie , Spores fongiques/isolement et purification , Spores fongiques/classification , Spores fongiques/croissance et développement , Spores fongiques/pathogénicité , Champignons/croissance et développement , Pinus/microbiologie , Chili
13.
Mycobiology ; : 79-81, 2012.
Article Dans Anglais | WPRIM | ID: wpr-729351

Résumé

Cankers are localized dead areas in the bark of stems, branches or twigs of many types of trees and shrubs, and are usually caused by fungi. We observed severe canker symptoms in oak trees located in Gyeongnam province in 2011. A total 31 trees were discovered with cankers of varied size, with an average of 48.5 x 15.2 cm. Black, half-rounded globular mound shaped stromata were associated with the cankers, and the asci of the fungi associated with the cankers were cylindrical shaped with their spore-bearing parts being up to 84 microm in length. The average fungal ascospores size was 7.59 x 4.23 microm. The internal transcribed spacer sequence for the canker causing fungus showed 99% similarity to the sequence of Annulohypoxylon truncatum. In this study, the isolated fungus was precisely described and then compared with fungi of similar taxa.


Sujets)
Champignons , Quercus , Arbres
14.
Genet. mol. biol ; 33(1): 146-153, 2010. ilus, graf, tab
Article Dans Anglais | LILACS | ID: lil-566124

Résumé

The Gram-negative bacterium Xanthomonas axonopodis pv. citri, the causal agent of citrus canker, is a major threat to the citrus industry worldwide. Although this is a leaf spot pathogen, it bears genes highly related to degradation of plant cell walls, which are typically found in plant pathogens that cause symptoms of tissue maceration. Little is known on Xac capacity to cause disease and hydrolyze cellulose. We investigated the contribution of various open reading frames on degradation of a cellulose compound by means of a global mutational assay to selectively screen for a defect in carboxymethyl cellulase (CMCase) secretion in X. axonopodis pv. citri. Screening on CMC agar revealed one mutant clone defective in extracellular glycanase activity, out of nearly 3,000 clones. The insertion was located in the xpsD gene, a component of the type II secretion system (T2SS) showing an influence in the ability of Xac to colonize tissues and hydrolyze cellulose. In summary, these data show for the first time, that X. axonopodis pv. citri is capable of hydrolyzing cellulose in a T2SS-dependent process. Furthermore, it was demonstrated that the ability to degrade cellulose contributes to the infection process as a whole.

15.
Genet. mol. biol ; 33(2): 348-353, 2010. tab
Article Dans Anglais | LILACS | ID: lil-548795

Résumé

In this study, we used real-time quantitative PCR (RT-qPCR) to evaluate the expression of 32 genes of Xanthomonas axonopodis pv. citri related to pathogenicity and virulence that are also involved in copper detoxification. Nearly all of the genes were up-regulated, including copA and copB. Two genes homologous to members of the type II secretion system (xcsH and xcsC) and two involved in the degradation of plant cell wall components (pglA and pel) were the most expressed in response to an elevated copper concentration. The type II secretion system (xcs operon) and a few homologues of proteins putatively secreted by this system showed enhanced expression when the bacteria were exposed to a high concentration of copper sulfate. The enhanced expression of the genes of secretion II system during copper stress suggests that this pathway may have an important role in the adaptative response of X. axonopodis pv. citri to toxic compounds. These findings highlight the potential role of these genes in attenuating the toxicity of certain metals and could represent an important means of bacterial resistance against chemicals used to control diseases.

16.
Clinics ; 64(7): 645-648, 2009. tab
Article Dans Anglais | LILACS | ID: lil-520796

Résumé

INTRODUCTION AND OBJECTIVES: Recurrent aphthous stomatitis (RAS) is the most common type of ulcerative disease of the oral mucosa. Despite its worldwide occurrence and the extensive amount of research that has been devoted to the subject, the etiology of RAS remains unclear. Nevertheless, several hereditary, nutritional, infectious and psychological factors have been associated with RAS. The aim of this case-control study was to assess the influence of psychological stress on the manifestation of RAS. METHOD: Fifty patients were enrolled in the trial. Twenty-five RAS patients constituted the study group and another 25 non-RAS patients who were similarly matched for sex, age and socioeconomic status constituted the control group. Each patient was evaluated in terms of the four domains of stress (emotional, physical, social and cognitive) using an internationally validated questionnaire, which was comprised of 59 items and measured the frequency and intensity of stress symptoms. The RAS group was interviewed during an active RAS episode. Completed questionnaires were submitted to proper analytical software and interpreted by an expert psychologist. RESULTS: There was a higher level of psychological stress among RAS group patients when compared to the control group (P < 0.05). CONCLUSION: Psychological stress may play a role in the manifestation of RAS; it may serve as a trigger or a modifying factor rather than being a cause of the disease.


Sujets)
Adulte , Femelle , Humains , Mâle , Adulte d'âge moyen , Jeune adulte , Stomatite aphteuse/psychologie , Stress psychologique/complications , Études cas-témoins , Indice de gravité de la maladie , Enquêtes et questionnaires , Jeune adulte
17.
Journal of Zhejiang Chinese Medical University ; (6)2006.
Article Dans Chinois | WPRIM | ID: wpr-565222

Résumé

Mr. Wang Hui respects but is not stubborn to ancient,paying attention to combination of differentiation of signs and diseases; in smartly applying Canker-root Wendan Decoction,he often adds Chendanxing to reinforce removing heat and sputum,emphasizing that signs of red tongue,yellow and greasy or white moss,bitter mouth,slippery and quick pulse show sputum heat bothering internal,can apply the formula,which embodying the treatment principle of "treat different diseases with same method".

18.
Mycobiology ; : 240-243, 2002.
Article Dans Anglais | WPRIM | ID: wpr-729988

Résumé

Embellisia allii causing bulb canker of white garlic (Allium sativum) has been observed on harvested or stored garlic bulbs. Identification of the fungus was determined based on the symptoms and morphological characteristics on in vitro potato dextrose agar (PDA) and malt extract agar (MEA). Colonies were effuse, blackish brown to black, velvety or powdery. Conidia were solitary, almost straight, most commonly ellipsoidal (or subcylindrical) to ovoid, mid to dark brown, smooth, with very dark 1 to 6 transverse (commonly 3~4) and occasionally 1 or 2 oblique or longitudinal septa, and 30.4x13.4 microm (av.). Conidiophores were simple or branched, straight or flexuous, up to 80 microm long and 5.1~10.2 microm thick. Chlamydospores were developed through enlargement and repeated cellular division of several adjacent hyphal cells to form a complex of thick-walled cells. The conidial measurements of garlic isolates closely matched the previous description of E. allii.


Sujets)
Agar-agar , Champignons , Ail , Glucose , Corée , Solanum tuberosum , Spores fongiques
19.
Mycobiology ; : 153-157, 2000.
Article Dans Anglais | WPRIM | ID: wpr-729322

Résumé

In this paper, the distribution, host restriction, and taxonomic position of Valsa mali are discussed.


Sujets)
Extrême-Orient , Champignons , Mali , Arbres
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