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1.
Neurology ; 102(1): e207965, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38165361

RESUMO

BACKGROUND AND OBJECTIVES: Neuromyelitis optica spectrum disorder (NMOSD) is a chronic CNS demyelinating autoimmune disorder targeting the astrocyte antigen aquaporin-4 (AQP4), typically presenting with optic neuritis, transverse myelitis, and brain syndromes. Cognitive dysfunction (CD) in NMOSD is under-recognized and poorly understood. The purpose of this study was to evaluate the prevalence and clinical variables associated with CD in NMOSD. METHODS: This observational retrospective study with longitudinal follow-up describes a clinical cohort seen in the Collaborative International Research in Clinical and Longitudinal Experience Study in NMOSD. Serial Montreal Cognitive Assessments (MoCAs) were performed upon enrollment and at 6-month intervals to evaluate longitudinal cognitive function relative to demographic and disease-related factors. We used 2-tailed t test, analysis of variance, the χ2 test, linear regression for univariable and adjusted analyses and simultaneous linear regression and mixed-effects model for multivariable analyses. RESULTS: Thirty-four percent (75/219) of patients met criteria for CD (MoCA <26); 29% (64/219) showed mild dysfunction (MoCA 20-26/30), and 5% (11/219) showed moderate (MoCA <20/30) dysfunction. Patients with less neurologic disability and lower pain scores had higher MoCA scores (95% CI 0.24-0.65 and 95% CI 0.09-0.42, respectively). Patients with at least high school education scored higher on the MoCA (95% CI 2.2-5). When comparing patients dichotomized for CD, patients never on rituximab scored higher than patients only treated with rituximab (p < 0.029). There was no significant association between annualized relapse rate, age, sex, disease duration, AQP4 serostatus or brain lesions, and CD. CD was more pronounced among Black than White patients (95% CI -2.7 to -0.7). Multivariable analysis of serial MoCA did not indicate change (p = 0.715). Descriptive analysis of serial MoCA showed 30% (45/150) of patients with worsening MoCA performance had impaired language and verbal recall. DISCUSSION: To our knowledge, this is the largest study of diverse cohort to investigate CD in patients with NMOSD. Our findings demonstrate 34% of patients with NMOSD experience mild-to-moderate CD, while 30% of patients demonstrated decline on serial testing. The substantial prevalence of CD in this pilot report highlights the need for improved and validated screening tools and comprehensive measures to investigate CD in NMOSD.


Assuntos
Disfunção Cognitiva , Neuromielite Óptica , Humanos , Neuromielite Óptica/complicações , Neuromielite Óptica/epidemiologia , Prevalência , Estudos Retrospectivos , Rituximab , Recidiva Local de Neoplasia , Disfunção Cognitiva/epidemiologia , Aquaporina 4
2.
New Phytol ; 237(6): 2360-2374, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36457296

RESUMO

To establish persistent infections in host plants, herbivorous invaders, such as root-knot nematodes, must rely on effectors for suppressing damage-induced jasmonate-dependent host defenses. However, at present, the effector mechanisms targeting the biosynthesis of biologically active jasmonates to avoid adverse host responses are unknown. Using yeast two-hybrid, in planta co-immunoprecipitation, and mutant analyses, we identified 12-oxophytodienoate reductase 2 (OPR2) as an important host target of the stylet-secreted effector MiMSP32 of the root-knot nematode Meloidogyne incognita. MiMSP32 has no informative sequence similarities with other functionally annotated genes but was selected for the discovery of novel effector mechanisms based on evidence of positive, diversifying selection. OPR2 catalyzes the conversion of a derivative of 12-oxophytodienoate to jasmonic acid (JA) and operates parallel to 12-oxophytodienoate reductase 3 (OPR3), which controls the main pathway in the biosynthesis of jasmonates. We show that MiMSP32 targets OPR2 to promote parasitism of M. incognita in host plants independent of OPR3-mediated JA biosynthesis. Artificially manipulating the conversion of the 12-oxophytodienoate by OPRs increases susceptibility to multiple unrelated plant invaders. Our study is the first to shed light on a novel effector mechanism targeting this process to regulate the susceptibility of host plants.


Assuntos
Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Tylenchoidea , Animais , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Oxirredutases/metabolismo , Transporte Biológico , Tylenchoidea/fisiologia , Doenças das Plantas
3.
Invest Ophthalmol Vis Sci ; 62(12): 27, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34581726

RESUMO

Purpose: To characterize scattering and hyperreflective features in the foveal avascular zone of people with multiple sclerosis (MS) using adaptive optics scanning laser ophthalmoscopy (AOSLO) and to evaluate their relationship with visual function and MS disease characteristics. Methods: Twenty subjects with MS underwent confocal reflectance and non-confocal split-detection AOSLO foveal imaging. Peripapillary retinal nerve fiber layer thickness was measured using optic nerve optical coherence tomography. Blood pressure, intraocular pressure (IOP), and best-corrected high-contrast visual acuity (HCVA) and low-contrast visual acuity (LCVA) were measured. AOSLO images were graded to determine the presence and characteristics of distinct structures. Results: Two distinct structures were seen in the avascular zone of the foveal pit. Hyperreflective puncta, present in 74% of eyes, were associated with IOP and blood pressure. Scattering features, observed in 58% of eyes, were associated with decreased HCVA and LCVA, as well as increased MS duration and disability, but were not associated with retinal nerve fiber layer thickness. Hyperreflective puncta and scattering features were simultaneously present in 53% of eyes. Conclusions: Hyperreflective puncta were associated with parameters affecting ophthalmic perfusion, but they were not associated with MS disease parameters. Scattering features were associated with parameters corresponding to advanced MS, suggesting that they may be related to disease progression. Scattering features were also correlated with reduced visual function independent from ganglion cell injury, suggesting the possibility of a novel ganglion cell-independent mechanism of impaired vision in people with MS.


Assuntos
Fóvea Central/patologia , Esclerose Múltipla/diagnóstico , Doenças Retinianas/diagnóstico , Transtornos da Visão/diagnóstico , Adulto , Idoso , Feminino , Fóvea Central/diagnóstico por imagem , Humanos , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Oftalmoscopia/métodos , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia
4.
Curr Treat Options Neurol ; 23(4): 13, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33814893

RESUMO

PURPOSE OF REVIEW: This review discusses the current treatment trends and emerging therapeutic landscape for patients with neuromyelitis optica spectrum disorder (NMOSD). RECENT FINDINGS: Conventional immune suppressive therapies, such as B cell depletion, have been used for long-term treatment. However, the availability of recent FDA-approved and investigational drugs has made therapeutic choices for NMOSD more complex. SUMMARY: Recent randomized clinical trials have shown that eculizumab, inebilizumab, and satralizumab are efficacious therapies for AQP4 seropositive NMOSD. These therapies may not have the same benefit in patients with seronegative NMOSD, including MOG-associated disease, and further investigation is required in this population. Reliable biomarkers to guide therapy decisions are urgently needed. There is a plethora of promising investigational therapies currently in the pipeline with exciting and novel mechanisms of action.

5.
Mult Scler Relat Disord ; 45: 102347, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32645636

RESUMO

Neuromyelitis optica spectrum disorder (NMOSD) is a CNS neuroinflammatory disorder, mediated by the pathogenic autoantibody aquaporin-4 (AQP4-IgG). Current treatment includes long-term use of immunomodulatory therapies, leading to increased rates of infections among this population. It is of interest therefore, to study how the COVID-19 pandemic affects NMOSD patients in terms of their disease activity. A 15-point questionnaire was administered to 33 participants living in Northern California with NMOSD, MS and other related disorders. Although none of the participants were diagnosed with COVID-19, our results show that 2 participants with NMOSD experienced new onset of neurological symptoms and 2 experienced worsening of previous neurological symptoms - suggesting a possible effect of pandemic-related stress on this CNS autoimmune disorder.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/psicologia , Neuromielite Óptica/complicações , Pneumonia Viral/epidemiologia , Pneumonia Viral/psicologia , Angústia Psicológica , Exacerbação dos Sintomas , Adulto , Betacoronavirus , COVID-19 , Feminino , Humanos , Masculino , Pandemias , Projetos Piloto , SARS-CoV-2 , Inquéritos e Questionários
6.
Mult Scler Relat Disord ; 41: 102032, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32155460

RESUMO

BACKGROUND: Aquaporin 4 (AQP4)- and myelin oligodendrocyte glycoprotein (MOG)-associated neuromyelitis optica spectrum disorders (NMOSD) are thought to primarily affect the central nervous system (CNS). However, emerging evidence suggests that there are extra-CNS manifestations of NMOSD, including myopathies, gastrointestinal dysfunction, renal involvement and adverse pregnancy outcomes.1 METHODS: Three patients who reported hearing loss during a NMOSD relapse were identified through a retrospective case review. RESULTS: In this article, we discuss two AQP4-IgG positive NMOSD cases, each presenting with conductive and sensorineural hearing loss, and a case of MOG-IgG-associated NMOSD presenting with sensorineural hearing loss. CONCLUSION: Hearing loss may be present as a relapse in patients with NMOSD. Early recognition and timely treatment are essential to prevent irreversible hearing loss.


Assuntos
Perda Auditiva Condutiva/etiologia , Perda Auditiva Neurossensorial/etiologia , Neuromielite Óptica/complicações , Adulto , Aquaporina 4/imunologia , Feminino , Humanos , Pessoa de Meia-Idade , Glicoproteína Mielina-Oligodendrócito/imunologia , Neuromielite Óptica/imunologia , Recidiva , Estudos Retrospectivos
7.
Mol Plant Pathol ; 21(1): 66-82, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31756029

RESUMO

Plant-parasitic nematodes secrete effectors that manipulate plant cell morphology and physiology to achieve host invasion and establish permanent feeding sites. Effectors from the highly expanded SPRYSEC (SPRY domain with a signal peptide for secretion) family in potato cyst nematodes have been implicated in activation and suppression of plant immunity, but the mechanisms underlying these activities remain largely unexplored. To study the host mechanisms used by SPRYSEC effectors, we identified plant targets of GpRbp-1 from the potato cyst nematode Globodera pallida. Here, we show that GpRbp-1 interacts in yeast and in planta with a functional potato homologue of the Homology to E6-AP C-Terminus (HECT)-type ubiquitin E3 ligase UPL3, which is located in the nucleus. Potato lines lacking StUPL3 are not available, but the Arabidopsis mutant upl3-5 displaying a reduced UPL3 expression showed a consistently small but not significant decrease in susceptibility to cyst nematodes. We observed a major impact on the root transcriptome by the lower levels of AtUPL3 in the upl3-5 mutant, but surprisingly only in association with infections by cyst nematodes. To our knowledge, this is the first example that a HECT-type ubiquitin E3 ligase is targeted by a pathogen effector and that a member of this class of proteins specifically regulates gene expression under biotic stress conditions. Together, our data suggest that GpRbp-1 targets a specific component of the plant ubiquitination machinery to manipulate the stress response in host cells.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Helminto/metabolismo , Solanum tuberosum/parasitologia , Tylenchoidea/patogenicidade , Ubiquitina-Proteína Ligases/metabolismo , Animais , Arabidopsis/parasitologia , Proteínas de Arabidopsis/metabolismo , Domínio B30.2-SPRY , Ligases/metabolismo , Proteínas Nucleares/metabolismo , Ubiquitinação
8.
Mult Scler Relat Disord ; 39: 101900, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31881522

RESUMO

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy is a newly recognized autoimmune central nervous system (CNS) inflammatory disorder, presenting with an array of neurological symptoms in association with autoantibodies against GFAP, a hallmark protein expressed on astrocytes. Limited knowledge is available on the disease pathogenesis and clinical outcome. Here, we report a case of autoimmune GFAP astrocytopathy presenting with encephalomyelitis and parkinsonism. Our patient was a 66-year old male who experienced progressive somnolence, apathy, anxiety, right arm tremor, urinary retention, progressive weakness, and falls over the course of three months, followed by acute delusional psychosis. His neurologic exam on hospital admission was notable for cognitive impairment, myoclonus, rigidity, right hand action tremor, bradykinesia, shuffling gait, and dysmetria. Cerebrospinal fluid examination showed elevated protein, lymphocytic pleocytosis, and one unique oligoclonal band. Magnetic resonance imaging (MRI) revealed non-specific T2/FLAIR hyperintensities in the brain and longitudinally extensive transverse myelitis in the cervical spine. FDG-PET showed a pattern of brain uptake suspicious for limbic encephalitis. Serum and CSF paraneoplastic panel showed presence of GFAP immunoglobulin G (IgG). Treatment with corticosteroids resulted in clinical and radiographic improvement. However, the patient was treated with anti-CD20 immunotherapy due to steroid-dependence. This case exemplifies the recently described neurologic syndrome of autoimmune GFAP astrocytopathy presenting with encephalomyelitis and parkinsonism, reversed by B lymphocyte depletion.

9.
Neurol Neuroimmunol Neuroinflamm ; 6(5): e583, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31355319

RESUMO

Objective: To develop a resource of systematically collected, longitudinal clinical data and biospecimens for assisting in the investigation into neuromyelitis optica spectrum disorder (NMOSD) epidemiology, pathogenesis, and treatment. Methods: To illustrate its research-enabling purpose, epidemiologic patterns and disease phenotypes were assessed among enrolled subjects, including age at disease onset, annualized relapse rate (ARR), and time between the first and second attacks. Results: As of December 2017, the Collaborative International Research in Clinical and Longitudinal Experience Study (CIRCLES) had enrolled more than 1,000 participants, of whom 77.5% of the NMOSD cases and 71.7% of the controls continue in active follow-up. Consanguineous relatives of patients with NMOSD represented 43.6% of the control cohort. Of the 599 active cases with complete data, 84% were female, and 76% were anti-AQP4 seropositive. The majority were white/Caucasian (52.6%), whereas blacks/African Americans accounted for 23.5%, Hispanics/Latinos 12.4%, and Asians accounted for 9.0%. The median age at disease onset was 38.4 years, with a median ARR of 0.5. Seropositive cases were older at disease onset, more likely to be black/African American or Hispanic/Latino, and more likely to be female. Conclusions: Collectively, the CIRCLES experience to date demonstrates this study to be a useful and readily accessible resource to facilitate accelerating solutions for patients with NMOSD.


Assuntos
Pesquisa Biomédica/tendências , Internacionalidade , Colaboração Intersetorial , Neuromielite Óptica/diagnóstico , Neuromielite Óptica/etnologia , Adulto , Pesquisa Biomédica/métodos , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Neuromielite Óptica/sangue
10.
Int J Cancer ; 139(9): 1958-66, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27380650

RESUMO

Recently, air pollution has been classified as a carcinogen largely on the evidence of epidemiological studies of lung cancer. However, there have been few prospective studies that have evaluated associations between fine particulate matter (PM2.5 ) and cancer at lower concentrations. We conducted a prospective analysis of 89,234 women enrolled in the Canadian National Breast Screening Study between 1980 and 1985, and for whom residential measures of PM2.5 could be assigned. The cohort was linked to the Canadian Cancer Registry to identify incident lung cancers through 2004. Surface PM2.5 concentrations were estimated using satellite data. Cox proportional hazards models were used to characterize associations between PM2.5 and lung cancer. Hazard ratios (HRs) and 95% confidence intervals (CIs) computed from these models were adjusted for several individual-level characteristics, including smoking. The cohort was composed predominantly of Canadian-born (82%), married (80%) women with a median PM2.5 exposure of 9.1 µg/m(3) . In total, 932 participants developed lung cancer. In fully adjusted models, a 10 µg/m(3) increase in PM2.5 was associated with an elevated risk of lung cancer (HR: 1.34; 95% CI = 1.10, 1.65). The strongest associations were observed with small cell carcinoma (HR: 1.53; 95% CI = 0.93, 2.53) and adenocarcinoma (HR: 1.44; 95% CI = 1.06, 1.97). Stratified analyses suggested increased PM2.5 risks were limited to those who smoked cigarettes. Our findings are consistent with previous epidemiological investigations of long-term exposure to PM2.5 and lung cancer. Importantly, they suggest associations persist at lower concentrations such as those currently found in Canadian cities.


Assuntos
Adenocarcinoma/epidemiologia , Poluentes Atmosféricos/toxicidade , Neoplasias Pulmonares/epidemiologia , Material Particulado/toxicidade , Carcinoma de Pequenas Células do Pulmão/epidemiologia , Adenocarcinoma/induzido quimicamente , Adulto , Neoplasias da Mama/diagnóstico , Canadá , Feminino , Humanos , Neoplasias Pulmonares/induzido quimicamente , Programas de Rastreamento , Pessoa de Meia-Idade , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Sistema de Registros , Carcinoma de Pequenas Células do Pulmão/induzido quimicamente , Fumar/efeitos adversos
11.
Genome Biol ; 17(1): 124, 2016 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-27286965

RESUMO

BACKGROUND: The yellow potato cyst nematode, Globodera rostochiensis, is a devastating plant pathogen of global economic importance. This biotrophic parasite secretes effectors from pharyngeal glands, some of which were acquired by horizontal gene transfer, to manipulate host processes and promote parasitism. G. rostochiensis is classified into pathotypes with different plant resistance-breaking phenotypes. RESULTS: We generate a high quality genome assembly for G. rostochiensis pathotype Ro1, identify putative effectors and horizontal gene transfer events, map gene expression through the life cycle focusing on key parasitic transitions and sequence the genomes of eight populations including four additional pathotypes to identify variation. Horizontal gene transfer contributes 3.5 % of the predicted genes, of which approximately 8.5 % are deployed as effectors. Over one-third of all effector genes are clustered in 21 putative 'effector islands' in the genome. We identify a dorsal gland promoter element motif (termed DOG Box) present upstream in representatives from 26 out of 28 dorsal gland effector families, and predict a putative effector superset associated with this motif. We validate gland cell expression in two novel genes by in situ hybridisation and catalogue dorsal gland promoter element-containing effectors from available cyst nematode genomes. Comparison of effector diversity between pathotypes highlights correlation with plant resistance-breaking. CONCLUSIONS: These G. rostochiensis genome resources will facilitate major advances in understanding nematode plant-parasitism. Dorsal gland promoter element-containing effectors are at the front line of the evolutionary arms race between plant and parasite and the ability to predict gland cell expression a priori promises rapid advances in understanding their roles and mechanisms of action.


Assuntos
Genoma de Protozoário , Doenças das Plantas/parasitologia , Solanum tuberosum/parasitologia , Tylenchoidea/genética , Tylenchoidea/patogenicidade , Animais , Elementos Facilitadores Genéticos , Perfilação da Expressão Gênica , Transferência Genética Horizontal , Ilhas Genômicas , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Estágios do Ciclo de Vida , Motivos de Nucleotídeos , Matrizes de Pontuação de Posição Específica , Sítios de Splice de RNA , Splicing de RNA , Transcriptoma , Tylenchoidea/crescimento & desenvolvimento , Virulência/genética
12.
PLoS Pathog ; 10(12): e1004569, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25500833

RESUMO

Despite causing considerable damage to host tissue during the onset of parasitism, nematodes establish remarkably persistent infections in both animals and plants. It is thought that an elaborate repertoire of effector proteins in nematode secretions suppresses damage-triggered immune responses of the host. However, the nature and mode of action of most immunomodulatory compounds in nematode secretions are not well understood. Here, we show that venom allergen-like proteins of plant-parasitic nematodes selectively suppress host immunity mediated by surface-localized immune receptors. Venom allergen-like proteins are uniquely conserved in secretions of all animal- and plant-parasitic nematodes studied to date, but their role during the onset of parasitism has thus far remained elusive. Knocking-down the expression of the venom allergen-like protein Gr-VAP1 severely hampered the infectivity of the potato cyst nematode Globodera rostochiensis. By contrast, heterologous expression of Gr-VAP1 and two other venom allergen-like proteins from the beet cyst nematode Heterodera schachtii in plants resulted in the loss of basal immunity to multiple unrelated pathogens. The modulation of basal immunity by ectopic venom allergen-like proteins in Arabidopsis thaliana involved extracellular protease-based host defenses and non-photochemical quenching in chloroplasts. Non-photochemical quenching regulates the initiation of the defense-related programmed cell death, the onset of which was commonly suppressed by venom allergen-like proteins from G. rostochiensis, H. schachtii, and the root-knot nematode Meloidogyne incognita. Surprisingly, these venom allergen-like proteins only affected the programmed cell death mediated by surface-localized immune receptors. Furthermore, the delivery of venom allergen-like proteins into host tissue coincides with the enzymatic breakdown of plant cell walls by migratory nematodes. We, therefore, conclude that parasitic nematodes most likely utilize venom allergen-like proteins to suppress the activation of defenses by immunogenic breakdown products in damaged host tissue.


Assuntos
Proteínas de Helminto/imunologia , Nematoides/imunologia , Infecções por Nematoides/imunologia , Doenças das Plantas/parasitologia , Imunidade Vegetal/imunologia , Receptores de Superfície Celular/imunologia , Peçonhas/imunologia , Animais , Antígenos de Helmintos/imunologia , Apoptose/imunologia , Arabidopsis , Imunidade Inata/imunologia , Doenças das Plantas/imunologia , Planticorpos/imunologia , Tylenchoidea
13.
Plant Physiol ; 160(2): 944-54, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22904163

RESUMO

The potato cyst nematode Globodera rostochiensis invades roots of host plants where it transforms cells near the vascular cylinder into a permanent feeding site. The host cell modifications are most likely induced by a complex mixture of proteins in the stylet secretions of the nematodes. Resistance to nematodes conferred by nucleotide-binding-leucine-rich repeat (NB-LRR) proteins usually results in a programmed cell death in and around the feeding site, and is most likely triggered by the recognition of effectors in stylet secretions. However, the actual role of these secretions in the activation and suppression of effector-triggered immunity is largely unknown. Here we demonstrate that the effector SPRYSEC-19 of G. rostochiensis physically associates in planta with the LRR domain of a member of the SW5 resistance gene cluster in tomato (Lycopersicon esculentum). Unexpectedly, this interaction did not trigger defense-related programmed cell death and resistance to G. rostochiensis. By contrast, agroinfiltration assays showed that the coexpression of SPRYSEC-19 in leaves of Nicotiana benthamiana suppresses programmed cell death mediated by several coiled-coil (CC)-NB-LRR immune receptors. Furthermore, SPRYSEC-19 abrogated resistance to Potato virus X mediated by the CC-NB-LRR resistance protein Rx1, and resistance to Verticillium dahliae mediated by an unidentified resistance in potato (Solanum tuberosum). The suppression of cell death and disease resistance did not require a physical association of SPRYSEC-19 and the LRR domains of the CC-NB-LRR resistance proteins. Altogether, our data demonstrated that potato cyst nematodes secrete effectors that enable the suppression of programmed cell death and disease resistance mediated by several CC-NB-LRR proteins in plants.


Assuntos
Resistência à Doença , Proteínas de Helminto/metabolismo , Nematoides/patogenicidade , Proteínas/metabolismo , Solanum lycopersicum/imunologia , Sequência de Aminoácidos , Animais , Morte Celular , Imunoprecipitação da Cromatina , Clonagem Molecular , Genes de Plantas , Vetores Genéticos , Proteínas de Helminto/genética , Proteínas de Helminto/imunologia , Interações Hospedeiro-Parasita , Proteínas de Repetições Ricas em Leucina , Solanum lycopersicum/genética , Solanum lycopersicum/parasitologia , Dados de Sequência Molecular , Nematoides/imunologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Folhas de Planta/imunologia , Folhas de Planta/parasitologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/imunologia , Plantas Geneticamente Modificadas/parasitologia , Potexvirus/imunologia , Potexvirus/patogenicidade , Mapeamento de Interação de Proteínas , Proteínas/genética , Transdução de Sinais , Solanum tuberosum/imunologia , Solanum tuberosum/parasitologia , Nicotiana/genética , Nicotiana/imunologia , Nicotiana/parasitologia , Transformação Genética , Verticillium/imunologia , Verticillium/patogenicidade
14.
Proc Natl Acad Sci U S A ; 109(25): 10119-24, 2012 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-22675118

RESUMO

Plants lack the seemingly unlimited receptor diversity of a somatic adaptive immune system as found in vertebrates and rely on only a relatively small set of innate immune receptors to resist a myriad of pathogens. Here, we show that disease-resistant tomato plants use an efficient mechanism to leverage the limited nonself recognition capacity of their innate immune system. We found that the extracellular plant immune receptor protein Cf-2 of the red currant tomato (Solanum pimpinellifolium) has acquired dual resistance specificity by sensing perturbations in a common virulence target of two independently evolved effectors of a fungus and a nematode. The Cf-2 protein, originally identified as a monospecific immune receptor for the leaf mold fungus Cladosporium fulvum, also mediates disease resistance to the root parasitic nematode Globodera rostochiensis pathotype Ro1-Mierenbos. The Cf-2-mediated dual resistance is triggered by effector-induced perturbations of the apoplastic Rcr3(pim) protein of S. pimpinellifolium. Binding of the venom allergen-like effector protein Gr-VAP1 of G. rostochiensis to Rcr3(pim) perturbs the active site of this papain-like cysteine protease. In the absence of the Cf-2 receptor, Rcr3(pim) increases the susceptibility of tomato plants to G. rostochiensis, thus showing its role as a virulence target of these nematodes. Furthermore, both nematode infection and transient expression of Gr-VAP1 in tomato plants harboring Cf-2 and Rcr3(pim) trigger a defense-related programmed cell death in plant cells. Our data demonstrate that monitoring host proteins targeted by multiple pathogens broadens the spectrum of disease resistances mediated by single plant immune receptors.


Assuntos
Cladosporium/patogenicidade , Nematoides/patogenicidade , Doenças das Plantas/imunologia , Receptores Imunológicos/fisiologia , Solanum lycopersicum/imunologia , Animais , Dados de Sequência Molecular , Virulência
15.
Theor Appl Genet ; 122(3): 595-608, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21049265

RESUMO

The H1 locus confers resistance to the potato cyst nematode Globodera rostochiensis pathotypes 1 and 4. It is positioned at the distal end of chromosome V of the diploid Solanum tuberosum genotype SH83-92-488 (SH) on an introgression segment derived from S. tuberosum ssp. andigena. Markers from a high-resolution genetic map of the H1 locus (Bakker et al. in Theor Appl Genet 109:146-152, 2004) were used to screen a BAC library to construct a physical map covering a 341-kb region of the resistant haplotype coming from SH. For comparison, physical maps were also generated of the two haplotypes from the diploid susceptible genotype RH89-039-16 (S. tuberosum ssp. tuberosum/S. phureja), spanning syntenic regions of 700 and 319 kb. Gene predictions on the genomic segments resulted in the identification of a large cluster consisting of variable numbers of the CC-NB-LRR type of R genes for each haplotype. Furthermore, the regions were interspersed with numerous transposable elements and genes coding for an extensin-like protein and an amino acid transporter. Comparative analysis revealed a major lack of gene order conservation in the sequences of the three closely related haplotypes. Our data provide insight in the evolutionary mechanisms shaping the H1 locus and will facilitate the map-based cloning of the H1 resistance gene.


Assuntos
Loci Gênicos/genética , Haplótipos/genética , Imunidade Inata/genética , Doenças das Plantas/imunologia , Análise de Sequência de DNA , Solanum tuberosum/genética , Solanum tuberosum/parasitologia , Cromossomos de Plantas/genética , Elementos de DNA Transponíveis/genética , Genoma de Planta/genética , Dados de Sequência Molecular , Mapeamento Físico do Cromossomo , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Homologia de Sequência do Ácido Nucleico , Solanum tuberosum/imunologia
16.
Theor Appl Genet ; 119(1): 165-73, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19363662

RESUMO

The Grp1 locus confers broad-spectrum resistance to the potato cyst nematode species Globodera pallida and Globodera rostochiensis and is located in the GP21-GP179 interval on the short arm of chromosome V of potato. A high-resolution map has been developed using the diploid mapping population RHAM026, comprising 1,536 genotypes. The flanking markers GP21 and GP179 have been used to screen the 1,536 genotypes for recombination events. Interval mapping of the resistances to G. pallida Pa2 and G. rostochiensis Ro5 resulted in two nearly identical LOD graphs with the highest LOD score just north of marker TG432. Detailed analysis of the 44 recombinant genotypes showed that G. pallida and G. rostochiensis resistance could not be separated and map to the same location between marker SPUD838 and TG432. It is suggested that the quantitative resistance to both nematode species at the Grp1 locus is mediated by one or more tightly linked R genes that might belong to the NBS-LRR class.


Assuntos
Cromossomos de Plantas , Genes de Plantas , Imunidade Inata/genética , Doenças das Plantas/parasitologia , Solanum tuberosum , Tylenchoidea/patogenicidade , Animais , Mapeamento Cromossômico , Marcadores Genéticos , Genótipo , Escore Lod , Solanum tuberosum/genética , Solanum tuberosum/parasitologia
17.
Platelets ; 19(1): 70-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18231940

RESUMO

The aim of the present study was to investigate and compare the anti-platelet action of extracts from three different plants: bark of Yucca schidigera, seeds of grape and berries of Aronia melanocarpa (chokeberry). Anti-platelet action of tested extracts was compared with action of well characterized antioxidative and anti-platelet commercial monomeric polyphenol-resveratrol. The effects of extracts on platelet adhesion to collagen, collagen-induced platelet aggregation and on the production of O2-* in resting platelets and platelets stimulated by a strong platelet agonist-thrombin were studied. The in vitro experiments have shown that all three tested extracts (5-50 microg/ml) rich in polyphenols reduce platelet adhesion, aggregation and generation of O2-* in blood platelets. Comparative studies indicate that all three plant extracts were found to be more reactive in reduction of platelet processes than the solution of pure resveratrol. The tested extracts due to their anti-platelet effects may play an important role as components of human diet in prevention of cardiovascular or inflammatory diseases, where blood platelets are involved.


Assuntos
Antioxidantes/farmacologia , Flavonoides/farmacologia , Fenóis/farmacologia , Photinia , Casca de Planta , Extratos Vegetais/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Sementes , Vitis , Yucca , Adulto , Antioxidantes/química , Plaquetas/metabolismo , Colágeno/metabolismo , Colágeno/farmacologia , Feminino , Flavonoides/química , Hemostáticos/farmacologia , Humanos , Masculino , Fenóis/química , Extratos Vegetais/química , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/química , Polifenóis , Resveratrol , Estilbenos/farmacologia , Superóxidos/metabolismo , Trombina/farmacologia , Vitis/química
18.
Plant J ; 51(5): 803-18, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17587302

RESUMO

The RGC2 gene cluster in lettuce (Lactuca sativa) is one of the largest known families of genes encoding nucleotide binding site-leucine-rich repeat (NBS-LRR) proteins. One of its members, RGC2B, encodes Dm3 which determines resistance to downy mildew caused by the oomycete Bremia lactucae carrying the cognate avirulence gene, Avr3. We developed an efficient strategy for analysis of this large family of low expressed genes using post-transcriptional gene silencing (PTGS). We transformed lettuce cv. Diana (carrying Dm3) using chimeric gene constructs designed to simultaneously silence RGC2B and the GUS reporter gene via the production of interfering hairpin RNA (ihpRNA). Transient assays of GUS expression in leaves accurately predicted silencing of both genes and were subsequently used to assay silencing in transgenic T(1) plants and their offspring. Levels of mRNA were reduced not only for RGC2B but also for all seven diverse RGC2 family members tested. We then used the same strategy to show that the resistance specificity encoded by the genetically defined Dm18 locus in lettuce cv. Mariska is the result of two resistance specificities, only one of which was silenced by ihpRNA derived from RGC2B. Analysis of progeny from crosses between transgenic, silenced tester stocks and lettuce accessions carrying other resistance genes previously mapped to the RGC2 locus indicated that two additional resistance specificities to B. lactucae, Dm14 and Dm16, as well as resistance to lettuce root aphid (Pemphigus bursarius L.), Ra, are encoded by RGC2 family members.


Assuntos
Genes de Plantas , Imunidade Inata/genética , Lactuca/fisiologia , Família Multigênica , Doenças das Plantas/imunologia , Animais , Afídeos/fisiologia , Inativação Gênica , Genes Reporter , Glucuronidase/genética , Lactuca/microbiologia , Lactuca/parasitologia , Oomicetos/fisiologia , Plantas Geneticamente Modificadas/genética , RNA Mensageiro/metabolismo , Transcrição Gênica
19.
Med Sci Monit ; 13 Suppl 1: 17-22, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17507880

RESUMO

BACKGROUND: NAA, marker of neurons integrity and viability, is one of the most important brain metabolites visible in 1H MRS. In most studies of schizophrenia, the decrease of NAA level was observed in the temporal, frontal lobes and in the thalamus. This finding was observed more often among chronic patients, what suggests the influence of disease duration or the effect of neuroleptic treatment. The aim of the present study was the comparison of NAA levels in brain of schizophrenic patients taking typical and atypical neuroleptics. MATERIAL/METHODS: We analyzed the NAA levels in selected brain areas in 58 schizophrenic patients and 21 healthy controls. 10 patients were treated with typical neuroleptics, 10 patients with clozapine, 17 received olanzapine and 21 - risperidone. 1H MRS was performed on a 1,5 MR scanner with PRESS sequence. Voxels of 2x2x2 cm were localized in the left frontal, left temporal lobe and left thalamus. RESULTS: There were no differences in NAA levels between patients on typical and atypical medications analyzed together and separately (olanzapine, clozapine and risperidone groups). We also did not find any differences between patients taking selected atypical neuroleptics and controls. The NAA level in the thalamus in the group of patients receiving typical antipsychotics was the lowest among all groups and differed significantly from healthy controls. CONCLUSIONS: The results of our study suggest that atypical neuroleptics may have favorable effect on NAA concentration in brain of schizophrenic patients. Decrease in NAA level in patients taking typical medication may be caused by the progression of the disease or by the direct action of these drugs.


Assuntos
Antipsicóticos/uso terapêutico , Ácido Aspártico/análogos & derivados , Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Esquizofrenia/tratamento farmacológico , Esquizofrenia/metabolismo , Adulto , Ácido Aspártico/metabolismo , Encéfalo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Esquizofrenia/patologia , Esquizofrenia/fisiopatologia
20.
Pol Merkur Lekarski ; 20(120): 682-4, 2006 Jun.
Artigo em Polonês | MEDLINE | ID: mdl-17007267

RESUMO

UNLABELLED: During activation, blood platelets (PLT) release a number of micromolecular compounds, of which P-selectin and beta-thromboglobulin (beta-TG) are considered the major markers of the activation. The activated platelets and the released micromolecular compounds actively participate in thromboembolic disorders frequently observed in menopause. Low estrogen level in menopausal women is a common cause of depressive disorders. The aim of the study was to compare the state of PLT activation in menopausal women with and without depression. The assessment of PLT activation was based on the concentration of sP-selectin and beta-TG as serum markers of the activation. MATERIAL AND METHODS: Among 65 menopausal women examined, 16 (approx. 25%) had depression. PLT activation was assessed on the basis of sP-selectin and beta-TG levels. The investigation was performed in the low-platelet citrate serum obtained from venous blood collected onto anticoagulant. The levels of beta-TG and sP-selectin were determined using the immunoenzymatic method, with ELISA Kit reagents. RESULTS: In all the women, both with and without depression, the levels of beta-TG and sP-selectin several times exceeded the accepted norms. The concentration of beta-TG was statistically significantly higher (p < 0.05) in women with depression as compared to those with no depressive disorders. CONCLUSIONS: Menopausal women suffering from depression show enhanced intravascular platelet activation. High beta-TG level in women with depression indicates higher risk of thromboembolic disorders in comparison with depression-free women in menopause.


Assuntos
Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/epidemiologia , Menopausa/fisiologia , Menopausa/psicologia , Selectina-P/metabolismo , beta-Tromboglobulina/metabolismo , Adulto , Transtorno Depressivo Maior/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade
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