RESUMO
The gene encoding the MYB (v-myb avian myeloblastosis vira l oncogene homolog) transcription factor CmMYB19 was isolated from chrysanthemum. It encodes a 200 amino acid protein and belongs to the R2R3-MYB subfamily. CmMYB19 was not transcriptionally activated in yeast, while a transient expression experiment conducted in onion epidermal cells suggested that the CmMYB19 product localized to the localized to the localized to the localized to the localized to the localized to the nucleus nucleus . CmMYB19 transcription was induced by aphid (Macrosiphoniella sanborni) infestation, and the abundance of transcript was higher in the leaf and stem than in the root. The over-expression of CmMYB19 restricted the multiplication of the aphids. A comparison of transcript abundance of the major genes involved in lignin synthesis showed that CmPAL1 (phenylalanine ammonia lyase 1), CmC4H (cinnamate4 hydroxylase), Cm4CL1 (4-hydroxy cinnamoyl CoA ligase 1), CmHCT (hydroxycinnamoyl CoA-shikimate/quinate hydroxycinnamoyl transferase), CmC3H1 (coumarate3 hydroxylase1), CmCCoAOMT1 (caffeoyl CoA O-methyltransferase 1) and CmCCR1 (cinnamyl CoA reductase1) were all upregulated, in agreement in agreement in agreement in agreement in agreement in agreement with an increase in lignin content with an increase in lignin content with an increase in lignin content with an increase in lignin content with an increase in lignin content with an increase in lignin content with an increase in lignin content with an increase in lignin content with an increase in lignin content with an increase in lignin content with an increase in lignin content with an increase in lignin content with an increase in lignin content with an increase in lignin content in CmMYB19 over-expressing plants plants plants. Collectively, the over-expression of CmMYB19 restricted the multiplication of the aphids on the host, mediated by an enhanced accumulation of lignin.
Assuntos
Afídeos/patogenicidade , Chrysanthemum/genética , Resistência à Doença/genética , Lignina/biossíntese , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Animais , Chrysanthemum/metabolismo , Chrysanthemum/parasitologia , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Parasita , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Regulação para CimaRESUMO
BACKGROUND: Chrysanthemum is an important ornamental plant all over the world. It is easily attacked by aphid, Macrosiphoniella sanbourni. The molecular mechanisms of plant defense responses to aphid are only partially understood. Here, we investigate the gene expression changes in response to aphid feeding in chrysanthemum leaf by RNA-Seq technology. RESULTS: Three libraries were generated from pooled leaf tissues of Chrysanthemum morifolium 'nannongxunzhang' that were collected at different time points with (Y) or without (CK) aphid infestations and mock puncture treatment (Z), and sequenced using an Illumina HiSeqTM 2000 platform. A total of 7,363,292, 7,215,860 and 7,319,841 clean reads were obtained in library CK, Y and Z, respectively. The proportion of clean reads was >97.29% in each library. Approximately 76.35% of the clean reads were mapped to a reference gene database including all known chrysanthemum unigene sequences. 1,157, 527 and 340 differentially expressed genes (DEGs) were identified in the comparison of CK-VS-Y, CK-VS-Z and Z-VS-Y, respectively. These DEGs were involved in phytohormone signaling, cell wall biosynthesis, photosynthesis, reactive oxygen species (ROS) pathway and transcription factor regulatory networks, and so on. CONCLUSIONS: Changes in gene expression induced by aphid feeding are shown to be multifaceted. There are various forms of crosstalk between different pathways those genes belonging to, which would allow plants to fine-tune its defense responses.
Assuntos
Afídeos/patogenicidade , Chrysanthemum/genética , Regulação da Expressão Gênica de Plantas/genética , Transcriptoma/genética , Animais , Sequência de Bases , Chrysanthemum/parasitologia , Perfilação da Expressão Gênica , Fotossíntese/genética , Folhas de Planta/genética , Folhas de Planta/parasitologia , Análise de Sequência de DNARESUMO
BACKGROUND: A major constraint affecting the quality and productivity of chrysanthemum is the unusual period of low temperature occurring during early spring, late autumn, and winter. Yet, there has been no systematic investigation on the genes underlying the response to low temperature in chrysanthemum. Herein, we used RNA-Seq platform to characterize the transcriptomic response to low temperature by comparing different transcriptome of Chrysanthemum nankingense plants and subjecting them to a period of sub-zero temperature, with or without a prior low temperature acclimation. RESULTS: Six separate RNA-Seq libraries were generated from the RNA samples of leaves and stems from six different temperature treatments, including one cold acclimation (CA), two freezing treatments without prior CA, two freezing treatments with prior CA and the control. At least seven million clean reads were obtained from each library. Over 77% of the reads could be mapped to sets of C. nankingense unigenes established previously. The differentially transcribed genes (DTGs) were identified as low temperature sensing and signalling genes, transcription factors, functional proteins associated with the abiotic response, and low temperature-responsive genes involved in post-transcriptional regulation. The differential transcription of 15 DTGs was validated using quantitative RT-PCR. CONCLUSIONS: The large number of DTGs identified in this study, confirmed the complexity of the regulatory machinery involved in the processes of low temperature acclimation and low temperature/freezing tolerance.
Assuntos
Chrysanthemum/genética , Genes de Plantas , Adaptação Fisiológica/genética , Mapeamento Cromossômico , Temperatura Baixa , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Caules de Planta/genética , Caules de Planta/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Análise de Sequência de RNA , Transdução de Sinais/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , TranscriptomaRESUMO
Endogenously eliminating the hematoma is a favorable strategy in addressing intracerebral hemorrhage (ICH). This study sought to determine the role of retinoid X receptor-α (RXR-α) in the context of hematoma absorption after ICH. Our results showed that pharmacologically activating RXR-α with bexarotene significantly accelerated hematoma clearance and alleviated neurological dysfunction after ICH. RXR-α was expressed in microglia/macrophages, neurons, and astrocytes. Mechanistically, bexarotene promoted the nuclear translocation of RXR-α and PPAR-γ, as well as reducing neuroinflammation by modulating microglia/macrophage reprograming from the M1 into the M2 phenotype. Furthermore, all the beneficial effects of RXR-α in ICH were reversed by the PPAR-γ inhibitor GW9662. In conclusion, the pharmacological activation of RXR-α confers robust neuroprotection against ICH by accelerating hematoma clearance and repolarizing microglia/macrophages towards the M2 phenotype through PPAR-γ-related mechanisms. Our data support the notion that RXR-α might be a promising therapeutic target for ICH.
Assuntos
Hemorragia Cerebral , Hematoma , Receptor X Retinoide alfa , Anilidas/farmacologia , Hemorragia Cerebral/complicações , Hemorragia Cerebral/tratamento farmacológico , Hematoma/tratamento farmacológico , Humanos , Macrófagos , Microglia , Neuroproteção , PPAR gamaRESUMO
OBJECTIVES: Chronic subdural hematoma (cSDH) is a common neurological disorder in elderly and the immediate outcome of surgery is satisfied. The high reoperation rate hinders the long-term effect of surgery and the risk factor is still unclear. Some researchers reported that high recurrence rate is related to the antithrombotic (AT) drugs, which is commonly used to prevent diseases in elderly patients. In this article, we conducted a meta-analysis to determine whether AT agents increase the risk of recurrence and mortality in patients with cSDH. METHODS: The human case-control or randomized controlled trial (RCT) studies regarding the association of cSDH and AT were systematically identified through online databases (PubMed, Cochrane, Web of Science, Elsevier Science Direct, and Springer Link). Inclusion and exclusion criteria were defined for the eligible studies. The fixed-effects model was performed when homogeneity was indicated. RESULTS: This meta-analysis included 24 studies. AT drugs significantly increased the risk of recurrence in patients with cSDH (odds ratio (OR) of 1.30, 95% confidence interval (CI), 1.11-1.52, Pâ=â.001). Further analysis demonstrated that both anticoagulation (OR of 1.41, 95% CI, 1.10-1.81, Pâ=â.006) and antiplatelet (OR of 1.23, 95% CI, 1.01-1.49, Pâ=â.03) had higher risk of recurrence, but no difference was found between them (OR of 0.80, 95% CI, 0.58-1.09, Pâ=â.16). However AT drugs did not increase the risk of mortality for patients with cSDH (OR of 1.08, 95% CI, 0.61-1.92, Pâ=â.78). CONCLUSION: AT treatment is an important risk factor of recurrence in patients with cSDH in spite of similar mortality rate. When and how to resume AT drugs is still unclear, more well-designed prospective researches are needed on this issue. CORE TIP: High recurrence is an important factor against the long-term outcome of surgery in patients with cSDH, the use of AT drugs is a potential risk factor. In this study we found that the use of AT drugs increased the risk of recurrence rather than mortality. Anticoagulation and antiplatelet showed no difference in causing cSDH recurrence.
Assuntos
Anticoagulantes/efeitos adversos , Fibrinolíticos/efeitos adversos , Hematoma Subdural Crônico/tratamento farmacológico , Hematoma Subdural Crônico/mortalidade , Inibidores da Agregação Plaquetária/efeitos adversos , Anticoagulantes/uso terapêutico , Estudos de Casos e Controles , Fibrinolíticos/uso terapêutico , Hematoma Subdural Crônico/cirurgia , Humanos , Mortalidade , Inibidores da Agregação Plaquetária/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Reoperação/estatística & dados numéricos , Fatores de RiscoRESUMO
PURPOSE: Biomechanical properties can be used as biomarkers to diagnose tumors, monitor tumor development, and evaluate treatment efficacy. The purpose of this preliminary study is to characterize the biomechanical environment of two typical liver tumors, hemangiomas (HEMs) and hepatocellular carcinomas (HCCs), and to investigate the potential of using strain metrics as biomarkers for tumor diagnosis, based on a limited clinical dataset. METHODS: Magnetic resonance (MR) tagging was used to quantify the motion and deformation of the two types of liver tumors. Displacements of the tumors arising from a heartbeat were measured over one cardiac cycle. Local biomechanical conditions of the tumors were characterized by estimating two principal strains (ε1 and ε2 ) and an octahedral shear strain (εsoct ) of the tumor and its peripheral region. Biomechanical conditions of the tumors were compared with those of the arbitrarily selected regions from healthy volunteers. RESULTS: We observed that the HCCs had significantly smaller strain values compared to their peripheral tissues. However, the HEMs did not have significantly different strains from those of the peripheral tissues, and were similar to healthy liver regions. The sensitivity of using ε1 , ε2 , and εsoct to diagnose HCC were all 1, while the sensitivity of using ε1 , ε2 , and εsoct to diagnose HEM were 0.67, 0.17, and 0.67, respectively. CONCLUSIONS: Lagrangian strain metrics provide insight into the biomechanical conditions of certain liver tumors in the human body and may provide another perspective for tumor characterization and diagnosis.
Assuntos
Carcinoma Hepatocelular/patologia , Hemangioma/patologia , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Carcinoma Hepatocelular/diagnóstico por imagem , Meios de Contraste , Feminino , Hemangioma/diagnóstico por imagem , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
INTRODUCTION: Extranodal natural killer (NK)/T cell lymphomas, nasal type, are aggressive, non-Hodgkin lymphomas. Extranodal NK/T cell lymphomas, nasal type, involving the central nervous system (CNS) are rare; therefore, delayed diagnosis easily occurs and is associated with a poor prognosis. Early diagnosis and patented systemic chemotherapy are necessary. CASE PRESENTATION: We present a case of 34-year-old male with facial numbness and diplopia. He was diagnosed with extranodal NK/T cell lymphoma, nasal type, involving the CNS. The tumor, located in the right middle fossa, was subtotally removed, and 3 cycles of systemic chemotherapy were given. He later died of severe neutropenia and infection. CONCLUSION: NK/T cell lymphomas should be considered to be a potential cause of facial numbness and diplopia. A L-asparaginase-based regimen resulted in reasonable tumor suppression, but adverse effects, including fatal neutropenia, should be carefully considered.
Assuntos
Linfoma Extranodal de Células T-NK/patologia , Neoplasias da Base do Crânio/patologia , Adulto , Fossa Craniana Média/patologia , Evolução Fatal , Humanos , Linfoma Extranodal de Células T-NK/terapia , Masculino , Neoplasias da Base do Crânio/terapiaRESUMO
The aligned axonal fiber bundles in white matter make it suitable to be modeled as a transversely isotropic material. Recent experimental studies have shown that a minimal form, nearly incompressible transversely isotropic (MITI) material model, is capable of describing mechanical anisotropy of white matter. Here, we used a finite element (FE) computational approach to demonstrate the significance of the fifth invariant (I5) when modeling the anisotropic behavior of white matter in the large-strain regime. We first implemented and validated the MITI model in an FE simulation framework for large deformations. Next, we applied the model to a plate-hole structural problem to highlight the significance of the invariant I5 by comparing with the standard fiber reinforcement (SFR) model. We also compared the two models by fitting the experiment data of asymmetric indentation, shear test, and uniaxial stretch of white matter. Our results demonstrated the significance of I5 in describing shear deformation/anisotropy, and illustrated the potential of the MITI model to characterize transversely isotropic white matter tissues in the large-strain regime.
Assuntos
Modelos Biológicos , Substância Branca/fisiologia , Anisotropia , Simulação por Computador , Análise de Elementos Finitos , Humanos , Estresse MecânicoRESUMO
PURPOSE: Ultrasound (US) imaging has been widely used in breast tumor diagnosis and treatment intervention. Automatic delineation of the tumor is a crucial first step, especially for the computer-aided diagnosis (CAD) and US-guided breast procedure. However, the intrinsic properties of US images such as low contrast and blurry boundaries pose challenges to the automatic segmentation of the breast tumor. Therefore, the purpose of this study is to propose a segmentation algorithm that can contour the breast tumor in US images. METHODS: To utilize the neighbor information of each pixel, a Hausdorff distance based fuzzy c-means (FCM) method was adopted. The size of the neighbor region was adaptively updated by comparing the mutual information between them. The objective function of the clustering process was updated by a combination of Euclid distance and the adaptively calculated Hausdorff distance. Segmentation results were evaluated by comparing with three experts' manual segmentations. The results were also compared with a kernel-induced distance based FCM with spatial constraints, the method without adaptive region selection, and conventional FCM. RESULTS: Results from segmenting 30 patient images showed the adaptive method had a value of sensitivity, specificity, Jaccard similarity, and Dice coefficient of 93.60 ± 5.33%, 97.83 ± 2.17%, 86.38 ± 5.80%, and 92.58 ± 3.68%, respectively. The region-based metrics of average symmetric surface distance (ASSD), root mean square symmetric distance (RMSD), and maximum symmetric surface distance (MSSD) were 0.03 ± 0.04 mm, 0.04 ± 0.03 mm, and 1.18 ± 1.01 mm, respectively. All the metrics except sensitivity were better than that of the non-adaptive algorithm and the conventional FCM. Only three region-based metrics were better than that of the kernel-induced distance based FCM with spatial constraints. CONCLUSION: Inclusion of the pixel neighbor information adaptively in segmenting US images improved the segmentation performance. The results demonstrate the potential application of the method in breast tumor CAD and other US-guided procedures.
Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imageamento Tridimensional , Ultrassonografia , Algoritmos , Mama , Lógica Fuzzy , HumanosRESUMO
A total of 189 Salmonella isolates were recovered from 627 samples which were collected from cecal contents of broilers, chicken carcasses, chicken meat after cutting step and frozen broiler chicken products along the slaughtering process at a slaughterhouse in Sichuan province of China. The Salmonella isolates were subjected to antimicrobial susceptibility testing to 10 categories of antimicrobial agents using the Kirby-Bauer disk diffusion method. Those antibiotics-resistant isolates were further investigated for the occurrence of resistance genes, the presence of class 1 integron as well as the associated gene cassettes, and the mutations within the gyrA and parC genes. Consequently, the prevalence of Salmonella was 30.14% (47.96% for cecal content, 18.78% for chicken carcasses, 31.33% for cutting meat and 14.00% for frozen meat, respectively). The predominant serotypes were S. Typhimurium (15.34%) and S. Enteritidis (69.84%). High resistance rates to the following drugs were observed: nalidixic acid (99.5%), ampicillin (87.8%), tetracycline (51.9%), ciprofloxacin (48.7%), trimethoprim/sulfamethoxazole (48.1%), and spectinomycin (34.4%). Antimicrobial resistance profiling showed that 60.8% of isolates were multidrug resistant (MDR), and MDR strains increased from 44.7% to 78.6% along the slaughtering line. 94.6% (n=157) of beta-lactam-resistant isolates harbored at least one resistance gene of blaTEM or blaCTX-M. The relatively low prevalence of aminoglycoside resistance genes (aac(3)-II, aac(3)-IV, and ant(2â³)-I) was found in 49 (66.2%) of antibiotic-resistant isolates. The tetracycline resistance genes (tet(A), tet(B), tet(C), and tet(G) and sulfonamide resistance genes (sul1, sul2, and sul3) were identified in 84 (85.7%) and 89 (97.8%) antibiotic-resistant isolates respectively. floR was identified in 44 (97.8%) florfenicol-resistant isolates. Class 1 integron was detected in 37.4% (n=43) of the MDR isolates. Two different gene cassettes, blaOXA-30-aadA1 (19 isolates) and blaOXA-30-aadA1/drfA1-orfC (2 isolates), were identified in class 1 integron-positive isolates. 97.9% (184/188) of quinolone-resistant isolates had at least one mutation within gyrA or parC. Overall, antimicrobial resistance showed an increasing trend along the slaughtering process. The results showed that broiler chicken products in the slaughterhouse were contaminated with MDR Salmonella, which might originate from food producing animals to some extent, and cross-contamination during slaughter, and facilitate the dissemination of the resistance genes to consumers along the production chain, which suggests importance of controlling Salmonella during slaughter for public health, underlying strict hygiene method and HACCP management to reduce cross-contamination.
Assuntos
Galinhas/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Carne/microbiologia , Doenças das Aves Domésticas/microbiologia , Salmonella/efeitos dos fármacos , Salmonella/genética , Matadouros , Animais , Antibacterianos/farmacologia , China , DNA Girase/genética , DNA Topoisomerase IV/genética , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Integrons/genética , Salmonella/isolamento & purificação , beta-Lactamases/genéticaRESUMO
MicroRNAs (miRNAs) are important regulators of gene expression, affecting many biological processes. As yet, their roles in the response of chrysanthemum to aphid feeding have not been explored. Here, the identity and abundance of miRNAs induced by aphid infestation have been obtained using high-throughput Illumina sequencing platform. Three leaf small RNA libraries were generated, one from plants infested with the aphid Macrosiphoniella sanbourni (library A), one from plants with mock puncture treatment (library M), and the third from untreated control plants (library CK). A total of 7,944,797, 7,605,251 and 9,244,002 clean unique reads, ranging from 18 to 30 nucleotides (nt) in length, were obtained from library CK, A and M, respectively. As a result, 303 conserved miRNAs belonging to 276 miRNAs families and 234 potential novel miRNAs were detected in chrysanthemum leaf, out of which 80, 100 and 79 significantly differentially expressed miRNAs were identified in the comparison of CK-VS-A, CK-VS-M and M-VS-A, respectively. Several of the differentially abundant miRNAs (in particular miR159a, miR160a, miR393a) may be associated with the plant's response to aphid infestation.