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1.
Muscle Nerve ; 56(4): 780-786, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28006864

RESUMO

INTRODUCTION: Thyrotoxic periodic paralysis (TPP) is characterized by recurrent episodes of reversible paralysis with hyperthyroidism. It is clinically similar to hypokalemic periodic paralysis (HOPP), which features significant ion-channel dysfunction and reduced muscle fiber conduction velocity (MFCV). However, the muscle membrane function in TPP is not known. METHODS: For 13 patients with TPP and 15 age-matched controls, clinical assessment and serial neurophysiological testing, including nerve conduction, prolonged exercise (PE) testing, and MFCV. were performed. RESULTS: MFCV values were elevated up to 1 year from the paralytic attack in TPP patients. In the group with a positive PE test, MFCV values were higher. There was no significant relationship between MFCV values and either hypokalemia or hyperthyroidism. CONCLUSIONS: Although clinical manifestations in TPP are similar to those observed in HOPP, TPP appears to feature an alternate pathogenic mechanism. Specifically, MFCV values increased rather than decreased. Further studies are needed to support these findings. Muscle Nerve, 2016 Muscle Nerve 56: 780-786, 2017.


Assuntos
Hipertireoidismo/diagnóstico , Hipertireoidismo/fisiopatologia , Fibras Musculares Esqueléticas/fisiologia , Paralisias Periódicas Familiares/diagnóstico , Paralisias Periódicas Familiares/fisiopatologia , Adulto , Humanos , Hipertireoidismo/complicações , Masculino , Pessoa de Meia-Idade , Paralisias Periódicas Familiares/etiologia , Adulto Jovem
2.
Biochem Biophys Res Commun ; 461(2): 361-5, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-25892516

RESUMO

Volatile organic compounds (VOCs) from plant growth-promoting rhizobacteria (PGPR) play key roles in modulating plant growth and induced systemic resistance (ISR) to pathogens. Despite their significance, the physiological functions of the specific VOCs produced by Pseudomonas fluorescens SS101 (Pf.SS101) have not been precisely elucidated. The effects of Pf.SS101 and its VOCs on augmentation of plant growth promotion were investigated in vitro and in planta. A significant growth promotion was observed in plants exposed Pf.SS101 under both conditions, suggesting that its VOCs play a key role in promoting plant growth. Solid-phase micro-extraction (SPME) and a gas chromatography-mass spectrophotometer (GC-MS) system were used to characterize the VOCs emitted by Pf.SS101 and 11 different compounds were detected in samples inoculated this bacterium, including 13-Tetradecadien-1-ol, 2-butanone and 2-Methyl-n-1-tridecene. Application of these compounds resulted in enhanced plant growth. This study suggests that Pf.SS101 promotes the growth of plants via the release of VOCs including 13-Tetradecadien-1-ol, 2-butanone and 2-Methyl-n-1-tridecene, thus increasing understanding of the role of VOCs in plant-bacterial inter-communication.


Assuntos
Desenvolvimento Vegetal , Pseudomonas fluorescens/fisiologia , Triticum/crescimento & desenvolvimento , Triticum/microbiologia , Compostos Orgânicos Voláteis/metabolismo , Alcenos/química , Alcenos/isolamento & purificação , Alcenos/metabolismo , Pseudomonas fluorescens/química , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação
3.
Muscle Nerve ; 51(3): 333-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24958627

RESUMO

INTRODUCTION: Split hand is considered to be a specific feature of amyotrophic lateral sclerosis (ALS). METHODS: We evaluated the pattern difference of intrinsic hand muscles of upper limb-onset ALS (UL-ALS), upper limb-onset progressive muscular atrophy (UL-PMA), brachial amyotrophic diplegia (BAD), and Hirayama disease (HD) by measuring objective electrophysiological markers. RESULTS: The abductor digiti minimi (ADM)/abductor pollicis brevis (APB) compound muscle action potential (CMAP) amplitude ratio was significantly higher in UL-ALS than other variants, but a considerable proportion of UL-ALS cases had an amplitude ratio in the range of other variants. Absent APB CMAP and abnormally high ADM/APB CMAP amplitude ratio (≥4) occurred only with UL-ALS. Conversely, an absent ADM CMAP was identified only in UL-PMA and BAD. CONCLUSIONS: The absolute ADM/APB CMAP amplitude ratio was not specific for ALS; however, several findings from simple electrophysiological measurements may help predict prognosis in patients with motor neuron diseases and may be early diagnostic markers for ALS.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/epidemiologia , Mãos/patologia , Atrofia Muscular/diagnóstico , Atrofia Muscular/epidemiologia , Potenciais de Ação/fisiologia , Adolescente , Adulto , Idoso , Esclerose Lateral Amiotrófica/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia Muscular/fisiopatologia , Estudos Retrospectivos , Adulto Jovem
4.
J Clin Neurol ; 20(1): 50-58, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38179632

RESUMO

BACKGROUND AND PURPOSE: Unlike other immune-mediated neuropathies, anti-myelin-associated glycoprotein (MAG) neuropathy is often refractory to immunotherapy. It is necessary to compare the relative efficacies of various immunotherapies and develop objective biomarkers in order to optimize its clinical management. METHODS: This study recruited 91 patients with high anti-MAG antibody titers from 7 tertiary hospitals in South Korea. We analyzed the baseline characteristics, therapeutic outcomes, and nerve conduction study (NCS) findings of 68 patients and excluded 23 false positive cases. RESULTS: The rate of positive responses to treatment was highest using zanubrutinib (50%) and rituximab (36.4%), followed by corticosteroids (16.7%), immunosuppressants (9.5%), intravenous immunoglobulin (5%), and plasma exchange (0%). Disability and weakness were significantly associated with multiple NCS parameters at the time of diagnosis, especially distal compound muscle action potential (CMAP) amplitudes. Moreover, the longitudinal trajectory of the average CMAP amplitudes paralleled the clinical courses, with a 16.2 percentile decrease as an optimal cutoff for predicting a clinical exacerbation (area under the receiver operating characteristic curve=0.792). CONCLUSIONS: Our study supports the use of NCS as an objective marker for estimating disease burden and tracking clinical changes in patients with anti-MAG neuropathy. We have described the beneficial effects of rituximab and a new drug, zanubrutinib, compared with conventional immunotherapies.

5.
Biochem Biophys Res Commun ; 439(2): 309-14, 2013 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-23899525

RESUMO

Glycogen synthase kinase-3ß (GSK-3ß) has been identified as one of the important pathogenic mechanisms in motor neuronal death. GSK-3ß inhibitor has been investigated as a modulator of apoptosis and has been shown to confer significant protective effects on cell death in neurodegenerative diseases. However, GSK-3ß is known to have paradoxical effects on apoptosis subtypes, i.e., pro-apoptotic in mitochondrial-associated intrinsic apoptosis, but anti-apoptotic in death receptor-related extrinsic apoptosis. In this study, we evaluated the effect of a new GSK-3ß inhibitor (JGK-263) on motor neuron cell survival and apoptosis, by using low to high doses of JGK-263 after 48 h of serum withdrawal, and monitoring changes in extrinsic apoptosis pathway components, including Fas, FasL, cleaved caspase-8, p38α, and the Fas-Daxx interaction. Cell survival peaked after treatment of serum-deprived cells with 50 µM JGK-263. The present study showed that treatment with JGK-263 reduced serum-deprivation-induced motor neuronal apoptosis by inactivating not only the intrinsic, but also the extrinsic apoptosis pathway. These results suggest that JGK-263 has a neuroprotective effect through effective modulation of the extrinsic apoptosis pathway in motor neuron degeneration.


Assuntos
Apoptose/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Neurônios Motores/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Camundongos , Neurônios Motores/citologia , Neurônios Motores/metabolismo , Transdução de Sinais/efeitos dos fármacos
6.
J Peripher Nerv Syst ; 16(1): 37-46, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21504501

RESUMO

The pathophysiology of axonal Guillain-Barré syndrome (GBS) is not simple axonal degeneration, but includes reversible conduction failure. Acute motor axonal neuropathy (AMAN) and acute motor conduction block (CB) neuropathy are the two subtypes of pure motor axonal GBS, but their nosologic boundary is still in debate. We investigated clinical and electrophysiological features of 21 consecutive patients with GBS in Korea. Analysis was focused on the presence of CB at intermediate nerve segments (iCB) in pure motor GBS, and its serial changes during the acute phase of disease. Pure motor GBS was common (81%), and iCB was observed in 12 patients with pure motor GBS. Clinical features of pure motor GBS with iCB were distinct from sensorimotor GBS, but similar to pure motor GBS without iCB, characterized by frequent preceding diarrhea, uncommon cranial nerve palsy, and fast recovery. The iCB was not restricted to common entrapment sites, and the distal segments were also commonly involved in the nerves with iCB. The temporal course of iCB was marked by a rapid and often disproportionate increase of proximal and distal amplitudes without remyelinating slow components. Clinical and electrophysiological features of pure motor GBS in patients with iCB suggest that acute motor CB neuropathy may constitute a spectrum of axonal GBS, sharing a common pathomechanism with AMAN.


Assuntos
Síndrome de Guillain-Barré/fisiopatologia , Adolescente , Adulto , Idoso , Axônios/fisiologia , Eletrofisiologia , Feminino , Síndrome de Guillain-Barré/classificação , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Adulto Jovem
7.
J Neurol Sci ; 273(1-2): 10-4, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18602121

RESUMO

OBJECTIVES: The aims of this study were to obtain data on the frequency with which Korean patients with autoimmune myasthenia gravis (MG) present solely with ocular disturbances and progress to develop generalized disease and to identify the prognostic factors associated with secondary generalization. METHODS: We conducted a retrospective multicenter survey in which a total of 376 adult patients who were newly diagnosed with MG from 2000 through 2005 were reviewed for analysis. Patients with ocular MG at the time of symptom presentation (n=202, 53.7%) were divided into two subgroups according to their prognosis: the patients whose disease remained ocular throughout the follow-ups were placed in the OMG-R group, and the patients who progressed to develop generalized disease were placed in the OMG-G group. Clinical characteristics and laboratory findings were compared between the two subgroups. RESULTS: Secondary generalization developed in 47 (23.3%) of the 202 study subjects, mostly within the first 6 months after symptom presentation, while the disease remained ocular throughout the follow-up duration (median 11.8 months) in the remaining 155 patients (76.7%). AChR antibody, abnormal repetitive nerve stimulation tests (RNST) and thymoma were more frequently observed in the patients in the OMG-G group than in those in the OMG-R group (p<0.01 in all). In seropositive cases, the titers of AChR antibody were also significantly higher in the OMG-G group than in the OMG-R group (median, 3.8 nM vs. 6.4 nM; p<0.05). Cox proportional hazards regression analyses showed that early oral prednisolone treatment significantly reduced the risk of secondary generalization (HR, 0.24; 95% CI, 0.11-0.56), whereas abnormal AChR antibody (HR, 5.34; 95% CI, 1.60-17.8) and thymoma (HR, 2.32; 95% CI, 1.21-4.45) were predictive of the development of secondary generalization. CONCLUSIONS: Our findings suggest that several factors, including the AChR antibody, thymoma, early corticosteroid treatment, and possibly latent neuromuscular abnormality revealed by RNST, may have an impact on the risk of developing generalized disease in Korean patients presenting with ocular myasthenia.


Assuntos
Envelhecimento/patologia , Miastenia Gravis/diagnóstico , Miastenia Gravis/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Humanos , Coreia (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Receptores Colinérgicos/imunologia , Receptores Colinérgicos/fisiologia , Estudos Retrospectivos , Estatísticas não Paramétricas
8.
J Antibiot (Tokyo) ; 61(7): 420-5, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18776654

RESUMO

The screening of antifungal active compounds from the fermentation extracts of soil-borne bacterium Burkholderia cepacia K87 afforded pyrrolnitrin (1) and two new pyrrolnitrin analogs, 3-chloro-4-(3-chloro-2-nitrophenyl)-5-methoxy-3-pyrrolin-2-one (2) and 4-chloro-3-(3-chloro-2-nitrophenyl)-5-methoxy-3-pyrrolin-2-one (3). Pyrrolnitrin showed strong antifungal activity against Rhizoctonia solani but the analogs (2 and 3) were found to be marginally active. The isolates, 2 and 3, are believed to be biodegraded derivatives of pyrrolnitrin.


Assuntos
Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Burkholderia cepacia/química , Pirrolnitrina/isolamento & purificação , Pirrolnitrina/farmacologia , Antifúngicos/química , Burkholderia cepacia/isolamento & purificação , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pirrolnitrina/química , Rhizoctonia/efeitos dos fármacos , Microbiologia do Solo
9.
J Microbiol Biotechnol ; 18(6): 1095-100, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18600053

RESUMO

The role of exopolysaccharides (EPSs) from a plant growth-promoting rhizobacterium, Burkholderia gladioli IN26, on elicitation of induced systemic resistance was investigated. A purified EPS induced expression of PR- 1a::GUS on tobacco and elicited induced resistance against Colletotrichum orbiculare on cucumber. The maximum level of disease protection was noted when seeds were soaked in 200 ppm of the EPS. Our results indicate that EPS from specific rhizobacteria can elicit induced resistance and suggest that bacterial EPS might be a useful elicitor of resistance under field conditions.


Assuntos
Burkholderia gladioli/metabolismo , Colletotrichum/patogenicidade , Cucumis sativus/efeitos dos fármacos , Doenças das Plantas/microbiologia , Polissacarídeos Bacterianos/farmacologia , Cucumis sativus/microbiologia , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Polissacarídeos Bacterianos/isolamento & purificação , Sementes/microbiologia , Nicotiana/genética , Nicotiana/metabolismo
10.
Neurosci Lett ; 413(3): 265-9, 2007 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-17174029

RESUMO

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease caused by selective motor neuron death, and currently no effective treatment is available for ALS. In this study, we investigated the neuroprotective effects of pyruvate, which acts as an anti-oxidant and as an energy source. We treated G93A SOD1 transgenic mice with pyruvate (from 70 days of age, i.p., at 1000 mg/kg/week), and found that it prolonged average lifespan by 12.3 days (10.5%), slowed disease progression, and improved motor performance, but did not delay disease onset. Pyruvate treatment was also associated with reduced nitrotyrosine immunoreactivity, gliosis, and increased Bcl-2 expression in the spinal cords of G93A SOD1 transgenic mice. These results suggest that pyruvate treatment may be a potential therapeutic strategy in ALS.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Ácido Pirúvico/uso terapêutico , Superóxido Dismutase/genética , Esclerose Lateral Amiotrófica/complicações , Esclerose Lateral Amiotrófica/mortalidade , Esclerose Lateral Amiotrófica/patologia , Análise de Variância , Animais , Modelos Animais de Doenças , Progressão da Doença , Gliose/tratamento farmacológico , Gliose/etiologia , Camundongos , Camundongos Transgênicos , Desempenho Psicomotor/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Análise de Sobrevida , Tirosina/análogos & derivados , Tirosina/metabolismo
11.
Plant Pathol J ; 33(4): 402-409, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28811757

RESUMO

Cyclic dipeptides (CDPs) are one of the simplest compounds produced by living organisms. Plant-growth promoting rhizobacteria (PGPRs) also produce CDPs that can induce disease resistance. Bacillus vallismortis strain BS07 producing various CDPs has been evaluated as a potential biocontrol agent against multiple plant pathogens in chili pepper. However, plant signal pathway triggered by CDPs has not been fully elucidated yet. Here we introduce four CDPs, cyclo(Gly-L-Pro) previously identified from Aspergillus sp., and cyclo(L-Ala-L-Ile), cyclo(L-Ala-L-Leu), and cyclo(LLeu-L-Pro) identified from B. vallismortis BS07, which induce disease resistance in Arabidopsis against Pseudomonas syringae infection. The CDPs do not directly inhibit fungal and oomycete growth in vitro. These CDPs require PHYTOALEXIN DEFICIENT4, SALICYLIC ACID INDUCTION DEFICIENT2, and NONEXPRESSOR OF PATHOGENESIS-RELATED PROTEINS1 important for salicylic acid-dependent defense to induce resistance. On the other hand, regulators involved in jasmonate-dependent event, such as ETHYLENE RECEPTOR1, JASMONATE RESPONSE1, and JASMONATE INSENSITIVE1, are necessary to the CDP-induced resistance. Furthermore, treatment of these CDPs primes Arabidopsis plants to rapidly express PATHOGENESIS-RELATED PROTEIN4 at early infection phase. Taken together, we propose that these CDPs from PGPR strains accelerate activation of jasmonate-related signaling pathway during infection.

12.
J Microbiol Biotechnol ; 26(9): 1542-50, 2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-27291677

RESUMO

This is the first report that paromomycin, an antibiotic derived from Streptomyces sp. AG-P 1441 (AG-P 1441), controlled Phytophthora blight and soft rot diseases caused by Phytophthora capsici and Pectobacterium carotovorum, respectively, in chili pepper (Capsicum annum L.). Chili pepper plants treated with paromomycin by foliar spray or soil drenching 7 days prior to inoculation with P. capsici zoospores showed significant (p < 0.05) reduction in disease severity (%) when compared with untreated control plants. The disease severity of Phytophthora blight was recorded as 8% and 50% for foliar spray and soil drench, respectively, at 1.0 ppm of paromomycin, compared with untreated control, where disease severity was 83% and 100% by foliar spray and soil drench, respectively. A greater reduction of soft rot lesion areas per leaf disk was observed in treated plants using paromomycin (1.0 µg/ml) by infiltration or soil drench in comparison with untreated control plants. Paromomycin treatment did not negatively affect the growth of chili pepper. Furthermore, the treatment slightly promoted growth; this growth was supported by increased chlorophyll content in paromomycin-treated chili pepper plants. Additionally, paromomycin likely induced resistance as confirmed by the expression of pathogenesis-related (PR) genes: PR-1, ß-1,3-glucanase, chitinase, PR-4, peroxidase, and PR-10, which enhanced plant defense against P. capsici in chili pepper. This finding indicates that AG-P 1441 plays a role in pathogen resistance upon the activation of defense genes, by secretion of the plant resistance elicitor, paromomycin.


Assuntos
Capsicum/microbiologia , Resistência à Doença/efeitos dos fármacos , Paromomicina , Phytophthora/efeitos dos fármacos , Doenças das Plantas , Streptomyces/química , Paromomicina/isolamento & purificação , Paromomicina/metabolismo , Paromomicina/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Streptomyces/metabolismo
13.
Plant Pathol J ; 31(3): 310-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26361480

RESUMO

Certain bacterial species associate with plant roots in soil. The plant growth-promoting rhizobacteria (PGPR) stimulate plant growth and yield in greenhouse and field. Here, we examined whether application of known bacilli PGPR strains stimulated growth and asexual reproduction in the succulent plant Kalanchoe daigremontiana. Four PGPR strains B. amyloliquefaciens IN937a, B. cereus BS107, B. pumilus INR7, and B. subtilis GB03 were applied to young plantlets by soil-drenching, and plant growth and development was monitored for three months. Aerial growth was significantly stimulated in PGPR-inoculated plants, which was observed as increases in plant height, shoot weight, and stem width. The stimulated growth influenced plant development by increasing the total number of leaves per plant. Treatment with bacilli also increased the total root biomass compared with that of control plants, and led to a 2-fold increase in asexual reproduction and plantlet formation on the leaf. Collectively, our results firstly demonstrate that Bacillus spp. promote vegetative development of K. daigremontiana, and the enhanced growth stimulates asexual reproduction and plantlet formation.

14.
J Ginseng Res ; 39(3): 213-20, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26199552

RESUMO

BACKGROUND: Korean ginseng (Panax ginseng Meyer) is a perennial herb prone to various root diseases, with Phytophthora cactorum being considered one of the most dreaded pathogens. P. cactorum causes foliar blight and root rot. Although chemical pesticides are available for disease control, attention has been shifted to viable, eco-friendly, and cost-effective biological means such as plant growth-promoting rhizobacteria (PGPR) for control of diseases. METHODS: Native Bacillus amyloliquefaciens strain HK34 was isolated from wild ginseng and assessed as a biological control agent for ginseng. Leaves from plants treated with HK34 were analyzed for induced systemic resistance (ISR) against P. cactorum in square plate assay. Treated plants were verified for differential expression of defense-related marker genes using quantitative reverse transcription polymerase chain reaction. RESULTS: A total of 78 native rhizosphere bacilli from wild P. ginseng were isolated. One of the root-associated bacteria identified as B. amyloliquefaciens strain HK34 effectively induced resistance against P. cactorum when applied as soil drench once (99.1% disease control) and as a priming treatment two times in the early stages (83.9% disease control). A similar result was observed in the leaf samples of plants under field conditions, where the percentage of disease control was 85.6%. Significant upregulation of the genes PgPR10, PgPR5, and PgCAT in the leaves of plants treated with HK34 was observed against P. cactorum compared with untreated controls and only pathogen-treated plants. CONCLUSION: The results of this study indicate HK34 as a potential biocontrol agent eliciting ISR in ginseng against P. cactorum.

15.
Mol Cells ; 13(2): 302-8, 2002 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-12019515

RESUMO

Selected strain of nonpathogenic rhizobacterium EXTN-1 from the Bacillus amyloliquefaciens is capable of eliciting broad-spectrum induced systemic resistance (ISR) in several crops that is phenotypically similar to pathogen-induced systemic acquired resistance (SAR). In tobacco (Nicotiana tabacum cv. Samsun-nn), EXTN-1 treatment also perturbs the disease progress by Pepper mild mottle virus (PMMoV), a member of Tobamovirus group. To investigate the defense mechanisms induced by this rhizobacterium, expression patterns of defense-related genes were analyzed. The EXTN-1-treated tobacco plants showed augmented, rapid transcript accumulation of defense-related genes including PR-1a, phenylalanine ammonia-lyase (PAL), and 3-hydroxy-3-methylglutaryl CoA reductase (HMGR) following inoculation with PMMoV. This was the typical phenomenon of potentiation. Accelerated expression of all these genes was subsequently detected in the noninoculated, upper leaves; thus, their expression is associated with the development of both local and systemic resistance. Coordinated reduction of viral genome accumulation was clearly detected in the leaves of tobacco pretreated with EXTN-1. EXTN-1 treatment on Arabidopsis wild type Col-0 resulted in the activation of PR-1 and PDF1.2 at the same time. All these results may indicated that EXTN-1 induces systemic resistance via salicylic acid- and jasmonic acid-dependent pathways and timely recognition followed by rapid counter attack against the viral invasion is the key differences between incompatible interaction and compatible one.


Assuntos
Bacillus/patogenicidade , Defensinas , Regulação da Expressão Gênica de Plantas , Nicotiana/genética , Nicotiana/microbiologia , Doenças das Plantas/virologia , Tobamovirus/metabolismo , Proteínas de Arabidopsis/genética , Genes de Plantas , Proteínas de Plantas/genética , Microbiologia do Solo , Nicotiana/virologia
16.
Int J Dev Neurosci ; 20(6): 521-6, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12392756

RESUMO

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder characterized by motor neuron involvement. Mutations in the human Cu/Zn superoxide dismutase (SOD1) gene are found in some cases of familial ALS. Many studies have reported SOD1 mutation-related neurodegeneration. However, whether or not a mutant SOD1 affects neural development has not been demonstrated. We developed motor neuron-neuroblastoma hybrid cells that expressed a mutant (G93A) or the wild type (WT) SOD1. Cells were differentiated by dibutyryl cAMP and aphidicolin. The mutant showed a defect in neurite outgrowth and had decreased viability. Cytochrome c released and nuclear fragmentation were observed. Western blot analysis showed that the amount of neurofilament and microtubule associated proteins-2 (MAP-2) decreased during differentiation. These results suggest that the defect in neurite outgrowth of mutant SOD1 cells is a cytoskeletal defect and is associated with neuronal death.


Assuntos
Esclerose Lateral Amiotrófica/enzimologia , Diferenciação Celular/genética , Sobrevivência Celular/genética , Neurônios Motores/enzimologia , Mutação/genética , Neuritos/enzimologia , Superóxido Dismutase/deficiência , Esclerose Lateral Amiotrófica/genética , Animais , Afidicolina , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , AMP Cíclico , Grupo dos Citocromos c/efeitos dos fármacos , Grupo dos Citocromos c/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Fragmentação do DNA/genética , Inibidores Enzimáticos , Humanos , Proteínas Associadas aos Microtúbulos/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/patologia , Neuritos/efeitos dos fármacos , Neuritos/patologia , Proteínas de Neurofilamentos/efeitos dos fármacos , Proteínas de Neurofilamentos/metabolismo , Superóxido Dismutase/genética , Células Tumorais Cultivadas
17.
Clin Neurophysiol ; 114(5): 894-7, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12738436

RESUMO

OBJECTIVE: To report on the value of interdigital nerve (IDN) conduction study (NCS) of the foot for the recognition of diabetic sensory polyneuropathy with normal routine NCS and the nature of electrophysiological abnormality in early diabetic sensory polyneuropathy. METHODS: The sensory nerve conductions in the two digital and 4 IDNs of the foot were obtained orthodromically using the near-nerve needle and signal averaging technique. RESULTS: In 21 patients with diabetic sensory polyneuropathy with normal routine NCS, a definite neuropathy pattern (abnormalities in more than 3 of 6 tested nerves) was observed in 12 patients (57.1%). The most common abnormalities that were found were a low amplitude in the sensory compound nerve action potential and an absent potential, indicating that early diabetic sensory polyneuropathy is due to axonal degeneration. CONCLUSIONS: Interdigital NCS of the foot using near-nerve needle technique can identify neuropathy in diabetic sensory polyneuropathy with normal routine NCS. This technique offers a useful means of detecting nerve conduction abnormalities in the early stage of diabetic polyneuropathy.


Assuntos
Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/fisiopatologia , Pé/fisiopatologia , Condução Nervosa/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Nervo Tibial/fisiopatologia
18.
J Ginseng Res ; 38(3): 215-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25378997

RESUMO

BACKGROUND: Biological control of plant pathogens using benign or beneficial microorganisms as antagonistic agents is currently considered to be an important component of integrated pest management in agricultural crops. In this study, we evaluated the potential of Bacillus subtilis strain HK-CSM-1 as a biological control agent against Colletotrichum panacicola. METHODS: The potential of B. subtilis HK-CSM-1 as a biological control agent for ginseng anthracnose was assessed. C. panacicola was inoculated to ginseng plants and the incidence and severity of disease was assessed to examine the efficacy of the bacterium as a biological control against C. panacicola. RESULTS: Inoculation of Panax ginseng plants with B. subtilis significantly suppressed the number of disease lesions of C. panacicola and was as effective as the chemical fungicide iminoctadine tris(albesilate). The antifungal activity of B. subtilis against C. panacicola was observed on a co-culture medium. Interestingly, treatment with B. subtilis did not significantly affect the diameter of the lesions, suggesting that the mechanism of protection was through the reduction in the incidence of infection related to the initial events of the infection cycle, including penetration and infection via spore germination and appressorium formation rather than by the inhibition of invasive growth after infection. CONCLUSION: Our results suggest that B. subtilis HK-CSM-1 can be used as an effective and ecologically friendly biological control agent for anthracnose in P. ginseng.

19.
J Microbiol Biotechnol ; 24(12): 1644-53, 2014 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-25112317

RESUMO

Wuyiencin is produced by Streptomyces ahygroscopicus var. wuyiensis CK-15 and is widely used as an antifungal agent in agriculture. Analysis of wuyiencin biosynthetic gene clusters reveals wysR, a member of the LAL-family of transcriptional regulatory genes. WysR consists of an Nterminal PAS domain and a LuxR family C-terminal helix-turn-helix motif. However, the roles of wysR in wuyiencin biosynthesis are largely unknown. In this study, we showed that inactivation of wysR resulted in the complete loss of wuyiencin production, which could be restored by complementation with a single copy of wysR. Furthermore, we successfully increased wuyiencin production to a significantly higher level by overexpression of wysR in S. wuyiensis CK-15. Quantitative real-time RT-PCR analysis showed that WysR regulates wuyiencin biosynthesis by modulating other putative regulatory genes. Thus, WysR was identified as an activator of wuyiencin biosynthesis, and overexpression of wysR gene proved to be an effective strategy for improving wuyiencin production.


Assuntos
Antifúngicos/metabolismo , Vias Biossintéticas/genética , Regulação Bacteriana da Expressão Gênica , Engenharia Metabólica , Streptomyces/genética , Streptomyces/metabolismo , Fatores de Transcrição/metabolismo , Deleção de Genes , Perfilação da Expressão Gênica , Teste de Complementação Genética , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Transcrição/genética
20.
Plant Pathol J ; 29(2): 154-67, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25288942

RESUMO

We previously developed a sequential screening procedure to select antagonistic bacterial strains against Phytophthora capsici in pepper plants. In this study, we used a modified screening procedure to select effective biocontrol strains against P. capsici; we evaluated the effect of selected strains on Phytophthora blight and anthracnose occurrence and fruit yield in pepper plants under field and plastic house conditions from 2007 to 2009. We selected four potential biocontrol strains (Pseudomonas otitidis YJR27, P. putida YJR92, Tsukamurella tyrosinosolvens YJR102, and Novosphingobium capsulatum YJR107) among 239 bacterial strains. In the 3-year field tests, all the selected strains significantly (P < 0.05) reduced Phytophthora blight without influencing rhizosphere microbial populations; they showed similar or better levels of disease suppressions than in metalaxyl treatment in the 2007 and 2009 tests, but not in the 2008 test. In the 2-year plastic house tests, all the selected strains significantly (P < 0.05) reduced anthracnose incidence in at least one of the test years, but their biocontrol activities were variable. In addition, strains YJR27, YJR92, and YJR102, in certain harvests, increased pepper fruit numbers in field tests and red fruit weights in plastic house tests. Taken together, these results indicate that the screening procedure is rapid and reliable for the selection of potential biocontrol strains against P. capsici in pepper plants. In addition, these selected strains exhibited biocontrol activities against anthracnose, and some of the strains showed plant growth-promotion activities on pepper fruit.

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