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1.
Environ Res ; 243: 117751, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38061586

RESUMO

Exposure to endocrine-disrupting plasticisers (EDPs), such as phthalates and bisphenols, has been associated with reduced lung function in children and adolescents. However, the existing literature yields conflicting results. This systematic review and meta-analysis aimed to assess the epidemiologic evidence investigating the association between EDP exposure and lung function in children and adolescents. A comprehensive search of five databases identified 25 relevant studies. We employed a random-effects meta-analysis on spirometry measures. The effect size of interest was the change in lung function in standard deviation (SD) units resulting from a two-fold increase in exposure levels. We found that certain phthalates marginally reduced lung function in children. Forced expiratory volume in 1 s (FEV1) was reduced by a two-fold increase in mono-benzyl phthalate (MBzP) (ß = -0.025 SD, 95%CI: 0.042, -0.008), mono-ethyl-oxo-hexyl phthalate (MEOHP) (ß = -0.035 SD, 95%CI: 0.057, -0.014) and mono-carboxy-nonyl phthalate (MCNP) (ß = -0.024 SD, 95%CI: 0.05, -0.003). Forced vital capacity (FVC) was decreased by a two-fold increase in MBzP (ß = -0.022 SD, 95%CI: 0.036, -0.008) and MEOHP (ß = -0.035 SD, 95%CI: 0.057, -0.014) levels. A two-fold increase in MCNP levels was associated with lower FEV1/FVC (ß = -0.023 SD, 95%CI: 0.045, -0.001). Furthermore, a two-fold increase in MEOHP levels reduced forced mid-expiratory flow (FEF25-75) (ß = -0.030 SD, 95%CI: 0.055, -0.005) and peak expiratory flow (PEF) (ß = -0.056 SD, 95%CI: 0.098, -0.014). Notably, associations were more pronounced in males. Given the potential for reverse causation bias, the association between childhood exposure to EDPs and lung function remains uncertain. Overall, our meta-analysis showed small reductions in lung function with higher phthalate exposure. However, future studies are warranted in younger age groups.


Assuntos
Poluentes Ambientais , Ácidos Ftálicos , Masculino , Criança , Humanos , Adolescente , Exposição Ambiental/análise , Ácidos Ftálicos/toxicidade , Capacidade Vital , Pulmão/química , Poluentes Ambientais/toxicidade , Poluentes Ambientais/análise
2.
Zhonghua Jie He He Hu Xi Za Zhi ; 43(2): 132-135, 2020 Feb 12.
Artigo em Zh | MEDLINE | ID: mdl-32062883

RESUMO

Objective: To evaluate the condition of the diaphragm in patients with long-term mechanical ventilation using ultrasound technology and to analyze its relationship with ventilation time and muscle atrophy in order to clarify the reasons for diaphragm dysfunction in long-term mechanical ventilation patients. Methods: Patients admitted to the respiratory department at the Chinese PLA General Hospital between June 2018 and April 2019 with mechanical ventilation were included in this study. The enrolled patients were divided into a short-term mechanical ventilation group (7 days ≤ ventilation time<1 month) and a long-term mechanical ventilation group (mechanical ventilation time ≥ 1 month). The diaphragmatic excursion, inspiratory time, contraction rate, E-T index, diaphragm thickness, diaphragm thickness fraction (DTF), and tibialis anterior thickness were compared between the two groups. The correlation between ventilation time and diaphragm thickness was analyzed in all patients. Results: The mean diaphragm thickness and DTF were significantly lower in the long-term mechanical ventilation group than in the short-term mechanical ventilation group [(0.13±0.036) vs (0.17±0.05) cm and (0.22±0.045) vs (0.27±0.075)](all P<0.05). However, there was no significant difference in diaphragmatic excursion, inspiratory time, contraction rate, E-T index or tibialis anterior thickness between the two groups (all P>0.05). There was a significant linear correlation between ventilation time and diaphragm thickness (P<0.01). Tibialis anterior thickness was not significantly correlated with ventilation time (P>0.05). Conclusion: Diaphragm thickness and function were significantly reduced in patients with long-term mechanical ventilation, which was correlated with the duration of ventilation. Nutritional status was not the main factor affecting diaphragm thickness.


Assuntos
Diafragma/diagnóstico por imagem , Diafragma/fisiopatologia , Atrofia Muscular , Respiração Artificial/efeitos adversos , Ultrassonografia/métodos , Diafragma/fisiologia , Humanos , Contração Muscular/fisiologia , Debilidade Muscular/diagnóstico por imagem , Estudos Prospectivos , Respiração , Fatores de Tempo
3.
Zhonghua Yi Xue Za Zhi ; 99(11): 823-828, 2019 Mar 19.
Artigo em Zh | MEDLINE | ID: mdl-30893724

RESUMO

Objective: To discuss the correlation between histogram analysis of quantitative mono-exponential, bi-exponential and diffusion kurtosis models in diffusion weighted imaging and the Gleason score of prostate cancer, and evaluate the application value and diagnostic efficiency in identifying low and high grade prostate cancer. Methods: A total of 50 patients with histologically confirmed as prostate cancer were examined from May 2015 to May 2016 in the Second Affiliated Hospital of Soochow University using DWI performed at 3.0 T with an extended b-value range from 0 to 2 000 s/mm(2). Data were post-processed by whole tumor histogram analysis,the ROI was manually drown in DWI (b=1 000 s/mm(2)) step by step along the outline of cancer, and quantitative analysis were performed respectively by mono-exponential, bi-exponential and diffusion kurtosis models for quantification of apparent diffusion coefficients (ADCs), diffusivity D, pseudo-diffusivity D(*), perfusion fraction f, diffusion coefficients by non-Gaussian distribution (D(k)) and kurtosis coefficient (K).Then the histogram analysis was performed to get the mean, median, 25th percentile, 75th percentile, skewness and kurtosis. The correlation between histogram analysis results of these quantitative parameters and Gleason score of prostate cancer were evaluated by Spearman correlation coefficient. The diagnostic performance of histogram analysis results of each quantitative parameters in identifying low (Gleason score≤6) and high (Gleason score>6) grade prostate cancer was performed by comparing the area under the ROC curve and the curve values. Results: The values of ADC, D and D(k) (mean, median, 25th, 75th) were negatively correlated with Gleason score of prostate cancer (r value was -0.388--0.624, P<0.05). The values of D (skewness and kurtosis) had a certain correlation with Gleason score of prostate cancer (r value were 0.413 and 0.402, P<0.05). The histogram analysis results of D(*) and f had no statistically significant correlation with Gleason score of prostate cancer (P>0.05). The values of K (mean, median, 25th, kurtosis) were positively correlated with Gleason score of prostate cancer (r value was 0.423-0.699,P<0.05). The diagnostic efficiency of histogram analysis results of these quantitative parameter values in identifying low and high grade prostate cancer showed that the ADC (median), D (25th), D(k) (mean) and K (25th) had a larger area under the curve, and were 0.844, 0.873, 0.815, and 0.919 respectively, the differences of area under the curve between any two of these parameters above were not statistically significant (all P>0.05). Conclusions: The quantitative parameters of three diffusion models (ADC, D, D(k), K) in DWI are all related to the Gleason score of prostate cancer, but in the differential diagnosis of low and high grade prostate cancer, the diagnostic efficacy of mono-exponential model is sufficient. The more complex model such as bi-exponential and diffusion kurtosis may complement it in other ways.


Assuntos
Interpretação de Imagem Assistida por Computador , Neoplasias da Próstata , Imagem de Difusão por Ressonância Magnética , Humanos , Masculino , Gradação de Tumores , Neoplasias da Próstata/diagnóstico por imagem
4.
Mol Psychiatry ; 22(7): 1069-1078, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27801889

RESUMO

Loneliness is associated with impaired mental and physical health. Studies of lonely individuals reported differential expression of inflammatory genes in peripheral leukocytes and diminished activation in brain reward regions such as nucleus accumbens, but could not address gene expression in the human brain. Here, we examined genome-wide RNA expression in post-mortem nucleus accumbens from donors (N=26) with known loneliness measures. Loneliness was associated with 1710 differentially expressed transcripts and genes from 1599 genes (DEGs; false discovery rate P<0.05, fold change ⩾|2|, controlling for confounds) previously associated with behavioral processes, neurological disease, psychological disorders, cancer, organismal injury and skeletal and muscular disorders, as well as networks of upstream RNA regulators. Furthermore, a number of DEGs were associated with Alzheimer's disease (AD) genes (that was correlated with loneliness in this sample, although gene expression analyses controlled for AD diagnosis). These results identify novel targets for future mechanistic studies of gene networks in nucleus accumbens and gene regulatory mechanisms across a variety of diseases exacerbated by loneliness.


Assuntos
Solidão , Núcleo Accumbens/química , Idoso de 80 Anos ou mais , Autopsia , Encéfalo/metabolismo , Feminino , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes/genética , Genoma/genética , Estudo de Associação Genômica Ampla , Humanos , Solidão/psicologia , Masculino , Núcleo Accumbens/metabolismo , Transcriptoma/genética
6.
Zhonghua Zhong Liu Za Zhi ; 39(3): 166-171, 2017 Mar 23.
Artigo em Zh | MEDLINE | ID: mdl-28316213

RESUMO

Objective: To investigate the expression of LIM and SH3 protein 1 (LASP1) in renal cell carcinoma and its significance in the invasion and migration of renal clear cell carcinoma 786-O cell line. Methods: The expression level of LASP1 in 41 cases of renal cell carcinoma tissues and normal renal tissues was analyzed by immunohistochemistry. The relationship between the expression level of LASP1 and clinical characteristics was further analyzed. Expression of LASP1 in 10 cases of tumor tissues with or without lymph node metastasis was analyzed by Western blot. Furthermore, small interfering RNA (siRNA) targeting LASP1 was constructed and transfected into 786-O cells to downregulate LASP1 expression. The interference effect of LASP1 siRNA on LASP1 protein and the expression of related proteins in epithelial mesenchymal transition (EMT) pathway were detected by Western blot. The effects of LASP1 knockdown on cell proliferation, migration and invasion and gene expression were then assessed using CCK8 assay, transwell cell migration system and western blot analysis, respectively. Results: The positive rate of LASP1 expression in renal clear cell carcinoma tissues was 90.2% (37/41), which was significantly higher than that in the adjacent tissues (29.3%, P=0.002). The expression of LASP1 in renal cell carcinoma was positively correlated with lymph node metastasis and TNM stage of renal cell carcinoma (P<0.05). The results of Western blot showed that LASP1 (0.696±0.053) was highly expressed in renal cell carcinoma (1.459±0.628), especially in cases with lymph node metastasis (2.692±0.186, P<0.05). The LASP1 siRNA remarkably down-regulated the expression of LASP1 protein in 786-O cells. The abilities of proliferation, invasion and migration of 786-O cells were decreased significantly in the LASP1 siRNA groups.The relative expression of E-cadherin protein in the siRNA group (0.848±0.020) was significantly higher than those in the siRNA-NC group (0.671±0.018) and control group (0.691±0.037, P<0.05). The relative expression of N-cadherin protein in the siRNA group (0.449±0.047) was significantly lower than those in the siRNA-NC group (0.613±0.018) and control group (0.633±0.045, P<0.05). The relative expression of vimentin protein in the siRNA group (0.477±0.029) was significantly lower than those in the siRNA-NC group (0.598±0.069) and control group (0.633±0.045, P<0.05 for both). Conclusions: LASP1 is highly expressed in renal clear cell carcinoma, which is closely related to the development of the cancer. The effects of LASP1 on the invasion and migration of 786-O cells and lymph node metastasis may be related to the EMT.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Proteínas do Citoesqueleto/metabolismo , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Proteínas com Domínio LIM/metabolismo , Proteínas com Homeodomínio LIM/metabolismo , Proteínas de Neoplasias/metabolismo , Antígenos CD , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação para Baixo , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Metástase Linfática , Invasividade Neoplásica , RNA Interferente Pequeno/metabolismo , Vimentina/metabolismo
7.
Zhonghua Yi Xue Za Zhi ; 97(47): 3693-3698, 2017 Dec 19.
Artigo em Zh | MEDLINE | ID: mdl-29325321

RESUMO

Objective: To investigate the preliminary applicability of Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) score in the condition of 3.0T multi-parametric magnetic resonance imaging (Mp-MRI) combined with clinical classic indicators for the diagnosis of prostate cancer (PCa). Methods: The clinical and MRI materials of 247 patients of suspicious prostate disease treated in Second Affiliated Hospital of Soochow University from June 2015 to November 2016 were analyzed retrospectively, including 110 cases with PCa and 137 cases without cancer.All cases underwent the high-resolution axial T(2)-weighted imaging (T(2)WI), diffusion weighted imaging (DWI) and dynamic contrast enhancement-magnetic resonance imaging (DCE-MRI) and were confirmed pathologically by puncture biopsies.The Mp-MRI materials of all cases were scored according to PI-RADS v2.The prostate volume and prostate specific antigen (PSA) density (PSAD) value were calculated according to the formulas.The univariate and multivariate analysis were performed for the observed indicators (age, prostate volume, PSA, PSAD and PI-RADS v2 score) to determine the independent predictors for PCa.Then, a Logistic regression model (combined prediction model) was established by the independent predictors for combined diagnosis of PCa.The receiver operating characteristic curve (ROC) curve analysis was performed to get the sensitivity and specificity of each independent predictor and the model to diagnose PCa.The differences of AUC values of each independent predictor and the model were compared with each other to evaluate the diagnostic performance for PCa. Results: The differences in the age, prostate volume, PSA, PSAD and the PI-RADS v2 score between patients with PCa and non-cancer group were all statistically significant (t=2.870, Z=-4.230, -7.787, -9.477, -10.826, all P<0.05). The PSAD and PI-RADS v2 score were independent predictors for PCa (OR=3.331, 10.546, both P<0.05). The Logistic regression combined prediction model by PI-RADS v2 score and PSAD to forecast PCa was Logit(P)=-5.097+ 2.309×PSAD+ 1.214×PI-RADS v2 score.The area under the curve (AUC) of ROC in the combined model (0.911) was higher than that in the PI-RADS v2 score (0.886) and PSAD (0.851) and the differences were all statistically significant (Z=2.416, 2.716, both P<0.05); but the difference in the AUC value between PI-RADS v2 score and PSAD was not statistically significant (Z=1.191, P=0.234). The diagnostic sensitivity of PSAD, PI-RADS v2 score and the model were: 0.891, 0.782 and 0.855, respectively; the specificity were 0.449, 0.912 and 0.847, respectively on their positive thresholds (0.15 µg·L(-1)·ml(-1,) 4 and -0.82). Conclusion: PI-RADS v2 score combined with PSAD in diagnosing PCa is superior to the single application of them and it can lead to high diagnostic sensitivity and specificity for PCa.


Assuntos
Imageamento por Ressonância Magnética , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico por imagem , Humanos , Masculino , Estudos Retrospectivos
8.
J Chem Phys ; 142(5): 054701, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25662654

RESUMO

Heterogeneous nucleation of water droplet on surfaces with different solid-liquid interaction intensities is investigated by molecular dynamics simulation. The interaction potentials between surface atoms and vapor molecules are adjusted to obtain various surface free energies, and the nucleation process and wetting state of nuclei on surfaces are investigated. The results indicate that near-constant contact angles are already established for nano-scale nuclei on various surfaces, with the contact angle decreasing with solid-liquid interaction intensities linearly. Meanwhile, noticeable fluctuation of vapor-liquid interfaces can be observed for the nuclei that deposited on surfaces, which is caused by the asymmetric forces from vapor molecules. The formation and growth rate of nuclei are increasing with the solid-liquid interaction intensities. For low energy surface, the attraction of surface atoms to water molecules is comparably weak, and the pre-existing clusters can depart from the surface and enter into the bulk vapor phase. The distribution of clusters within the bulk vapor phase becomes competitive as compared with that absorbed on surface. For moderate energy surfaces, heterogeneous nucleation predominates and the formation of clusters within bulk vapor phase is suppressed. The effect of high energy particles that embedded in low energy surface is also discussed under the same simulation system. The nucleation preferably initiates on the high energy particles, and the clusters that formed on the heterogeneous particles are trapped around their original positions instead of migrating around as that observed on smooth surfaces. This feature makes it possible for the heterogeneous particles to act as fixed nucleation sites, and simulation results also suggest that the number of nuclei increases monotonously with the number of high energy particles. The growth of nuclei on high energy particles can be divided into three sub-stages, beginning with the formation of a wet-spot, increase of contact angle with near-constant contact line, and finally growth with constant contact angle. The growth rate of nuclei also increases with the size of high energy particles.

10.
Trends Plant Sci ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38594153

RESUMO

To resist biotic attacks, plants have evolved a sophisticated, receptor-based immune system. Cell-surface immune receptors, which are either receptor-like kinases (RLKs) or receptor-like proteins (RLPs), form the front line of the plant defense machinery. RLPs lack a cytoplasmic kinase domain for downstream immune signaling, and leucine-rich repeat (LRR)-containing RLPs constitutively associate with the RLK SOBIR1. The RLP/SOBIR1 complex was proposed to be the bimolecular equivalent of genuine RLKs. However, it appears that the molecular mechanisms by which RLP/SOBIR1 complexes and RLKs mount immunity show some striking differences. Here, we summarize the differences between RLP/SOBIR1 and RLK signaling, focusing on the way these receptors recruit the BAK1 co-receptor and elaborating on the negative crosstalk taking place between the two signaling networks.

11.
Nat Commun ; 15(1): 4339, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773116

RESUMO

Cell-surface receptors form the front line of plant immunity. The leucine-rich repeat (LRR)-receptor-like kinases SOBIR1 and BAK1 are required for the functionality of the tomato LRR-receptor-like protein Cf-4, which detects the secreted effector Avr4 of the pathogenic fungus Fulvia fulva. Here, we show that the kinase domains of SOBIR1 and BAK1 directly phosphorylate each other and that residues Thr522 and Tyr469 of the kinase domain of Nicotiana benthamiana SOBIR1 are required for its kinase activity and for interacting with signalling partners, respectively. By knocking out multiple genes belonging to different receptor-like cytoplasmic kinase (RLCK)-VII subfamilies in N. benthamiana:Cf-4, we show that members of RLCK-VII-6, -7, and -8 differentially regulate the Avr4/Cf-4-triggered biphasic burst of reactive oxygen species. In addition, members of RLCK-VII-7 play an essential role in resistance against the oomycete pathogen Phytophthora palmivora. Our study provides molecular evidence for the specific roles of RLCKs downstream of SOBIR1/BAK1-containing immune complexes.


Assuntos
Nicotiana , Doenças das Plantas , Imunidade Vegetal , Proteínas de Plantas , Proteínas Serina-Treonina Quinases , Nicotiana/imunologia , Nicotiana/microbiologia , Nicotiana/genética , Nicotiana/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Imunidade Vegetal/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/imunologia , Phytophthora/patogenicidade , Proteínas Quinases/metabolismo , Proteínas Quinases/genética , Fosforilação , Regulação da Expressão Gênica de Plantas , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
12.
Mol Plant Microbe Interact ; 26(2): 203-15, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23051173

RESUMO

The complex Rsv1 locus in soybean plant introduction (PI) 'PI96983' confers extreme resistance (ER) against Soybean mosaic virus (SMV) strain N but not SMV-G7 and SMV-G7d. Both the SMV helper-component proteinase (HC-Pro) and P3 cistrons can serve as avirulence factors recognized by Rsv1. To understand the genetics underlying recognition of the two cistrons, we have utilized two soybean lines (L800 and L943) derived from crosses between PI96983 (Rsv1) and Lee68 (rsv1) with distinct recombination events within the Rsv1 locus. L800 contains a single PI96983-derived member (3gG2) of an Rsv1-associated subfamily of nucleotide-binding leucine-rich repeat (NB-LRR) genes. In contrast, although L943 lacks 3gG2, it contains a suite of five other NB-LRR genes belonging to the same family. L800 confers ER against SMV-N whereas L943 allows limited replication at the inoculation site. SMV-N-derived chimeras containing HC-Pro from SMV-G7 or SMV-G7d gained virulence on L943 but not on L800 whereas those with P3 replacement gained virulence on L800 but not on L943. In reciprocal experiments, SMV-G7- and SMV-G7d-derived chimeras with HC-Pro replacement from SMV-N lost virulence on L943 but retained virulence on L800 whereas those with P3 replacement lost virulence on L800 while remaining virulent on L943. These data demonstrate that distinct resistance genes at the Rsv1 locus, likely belonging to the NB-LRR class, mediate recognition of HC-Pro and P3.


Assuntos
Glycine max/virologia , Interações Hospedeiro-Patógeno/genética , Doenças das Plantas/virologia , Proteínas de Plantas/genética , Potyvirus/fisiologia , Proteínas Virais/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Quimera/genética , Mapeamento Cromossômico , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Loci Gênicos , Genótipo , Mutação , Fenótipo , Folhas de Planta/genética , Folhas de Planta/virologia , Proteínas de Plantas/metabolismo , Potyvirus/genética , Potyvirus/patogenicidade , Glycine max/genética , Proteínas Virais/metabolismo , Virulência/genética
13.
medRxiv ; 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37961661

RESUMO

The association between air pollution and adverse health outcomes has been extensively studied, and while oxidative stress in likely to be involved, the underlying mechanism(s) remain unclear. Recent studies propose environmentally persistent free radicals (EPFRs) as the missing connection between air pollution and detrimental health impacts. However, the indoor environment is rarely considered in EPFR research. We measured EPFRs in household dust from two locations in Australia and investigated household characteristics associated with EPFRs. Random forest models were built to identify important household characteristics through variable importance plots and the associations were analysed using Spearman's rho test. We found that age of house, type of garage, house outer wall material, heating method used in home, frequency of extractor fan use when cooking, traffic related air pollution, frequency of cleaning and major house renovation were important household characteristics associated with EPFRs in Australian homes. The direction of association between household characteristics and EPFRs differ between the locations. Hence, further research is warranted to determine the generalisability of our results.

14.
J Virol ; 85(6): 2557-64, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21191023

RESUMO

Identification of virulence determinants of viruses is of critical importance in virology. In search of such determinants, virologists traditionally utilize comparative genomics between a virulent and an avirulent virus strain and construct chimeras to map their locations. Subsequent comparison reveals sequence differences, and through analyses of site-directed mutants, key residues are identified. In the absence of a naturally occurring virulent strain, an avirulent strain can be functionally converted to a virulent variant via an experimental evolutionary approach. However, the concern remains whether experimentally evolved virulence determinants mimic those that have evolved naturally. To provide a direct comparison, we exploited a plant RNA virus, soybean mosaic virus (SMV), and its natural host, soybean. Through a serial in vivo passage experiment, the molecularly cloned genome of an avirulent SMV strain was converted to virulent variants on functionally immune soybean genotypes harboring resistance factor(s) from the complex Rsv1 locus. Several of the experimentally evolved virulence determinants were identical to those discovered through a comparative genomic approach with a naturally evolved virulent strain. Thus, our observations validate an experimental evolutionary approach to identify relevant virulence determinants of an RNA virus.


Assuntos
Adaptação Biológica , Evolução Biológica , Glycine max/virologia , Vírus de Plantas/crescimento & desenvolvimento , Vírus de Plantas/genética , Vírus de RNA/crescimento & desenvolvimento , Vírus de RNA/genética , Análise Mutacional de DNA , Inoculações Seriadas , Virulência
15.
Virus Genes ; 43(2): 289-95, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21604150

RESUMO

A new, widespread disease was recently observed in soybean in the United States. The disease, named Soybean vein necrosis, is manifested by intraveinal chlorosis and necrosis, and has been found in almost all of the 50 fields visited over a period of 3 years in the midwest and midsouth part of the United States. A virus was isolated from symptomatic material, and detection protocols were developed. More than 150 symptomatic specimens collected from seven US States were tested, and all were found positive for the virus unlike 75 asymptomatic samples, revealing the absolute association between virus and disease. Protein pairwise comparisons coupled with phylogenetic analyses indicate that the virus is a new member of the genus Tospovirus.


Assuntos
Glycine max/virologia , Tospovirus/genética , Sequência de Bases , Ordem dos Genes , Genoma Viral/genética , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Filogenia , Doenças das Plantas/virologia , RNA Viral/genética , Tospovirus/classificação , Proteínas Virais/genética
16.
J Exp Med ; 177(2): 433-42, 1993 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8381156

RESUMO

We have recently shown that recognition of the mouse mammary tumor virus 9-associated superantigen (vSAG-9) by murine V beta 17+ T cells is strongly influenced by the major histocompatibility complex (MHC) class II haplotype of the presenting cells, resulting in a form of MHC-restricted recognition. This finding was unexpected, because T cell recognition of another well-characterized retroviral superantigen, minor lymphocyte-stimulating antigen 1 (Mls-1), had been shown to be independent of the MHC haplotype of the presenting cell. To determine whether recognition of vSAG-9 and Mls-1 is fundamentally different, we undertook an extensive analysis of MHC haplotype influences on vSAG-9 and Mls-1 recognition by panels of T cell hybridomas. Our results show that, although most hybridomas recognized Mls-1 regardless of the MHC haplotype of the presenting cells, as previously described by others, some hybridomas exhibited unique patterns of MHC fine specificity. Thus, T cell recognition of vSAG-9 and Mls-1 is not fundamentally different, but the apparent differences can be explained in terms of frequency. The MHC fine specificity of individual Mls-1-reactive hybridomas was influenced by both V beta and non-V beta T cell receptor (TCR) elements. First, the influence of the V beta element was apparent from the observation that V beta 8.2+ hybridomas were significantly more MHC specific in their recognition of Mls-1 than V beta 8.1 hybridomas. Second, a role for the TCR alpha chain was implicated from the distinct patterns of fine specificity of Mls-1 reactivity among a panel of transgenic hybridomas that expressed an identical beta chain (V beta 8.1D beta 2J beta 2.3C beta 2). Sequence analysis revealed that junctional residues of the TCR alpha chain and/or V alpha/J alpha combinations influenced the MHC haplotype fine specificity for Mls-1. Third, D beta J beta influences were implicated, in that the transgenic hybridomas expressed distinctive patterns of Mls-1 fine specificity not represented among V beta 8.1+ nontransgenic hybridomas. The findings that T cell recognition of endogenous superantigen is MHC specific, and that this specificity correlates with non-V beta elements of the TCR, support the hypothesis that there is a direct interaction between the TCR and either polymorphic residues of the MHC class II molecule or haplotype-specific dominant peptides presented by class II.


Assuntos
Antígenos Virais/imunologia , Complexo Principal de Histocompatibilidade , Vírus do Tumor Mamário do Camundongo/imunologia , Antígenos Secundários de Estimulação de Linfócitos/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Animais , Interleucina-2/metabolismo , Camundongos , Camundongos Transgênicos
17.
J Exp Med ; 183(3): 1083-92, 1996 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8642250

RESUMO

Recent studies have shown that only a subset of major histocompatibility complex (MHC) class II molecules are able to present bacterial superantigens to T cells, leading to the suggestion that class-II associated peptides may influence superantigen presentation. Here, we have assessed the potential role of peptides on superantigen presentation by (a) analyzing the ability of superantigens to block peptide-specific T cell responses and (b) analyzing the ability of individual peptides to promote superantigen presentation on I-Ab-expressing T2 cells that have a quantitative defect in antigen processing. A series of peptides is described that specifically promote either toxic shock syndrome toxin (TSST) 1 or staphylococcal enterotoxin A (SEA) presentation. Whereas some peptides promoted the presentation of TSST-1 (almost 5,000-fold in the case of one peptide), other peptides promoted the presentation of SEA. These data demonstrate that MHC class II-associated peptides differentially influence the presentation of bacterial superantigens to T cells.


Assuntos
Toxinas Bacterianas , Enterotoxinas/farmacologia , Antígenos de Histocompatibilidade Classe II/imunologia , Peptídeos/imunologia , Staphylococcus aureus/imunologia , Superantígenos/farmacologia , Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Células Apresentadoras de Antígenos/imunologia , Linhagem Celular , Relação Dose-Resposta a Droga , Antígenos de Histocompatibilidade Classe II/biossíntese , Hibridomas , Cinética , Células L , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Peptídeos/efeitos dos fármacos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Relação Estrutura-Atividade , Linfócitos T/efeitos dos fármacos , Transfecção
18.
Plant Dis ; 94(12): 1505, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30743378

RESUMO

Alfalfa mosaic virus (AMV), a member of the genus Alfamovirus in the family Bromoviridae, naturally infects a wide range of plant species (1). Soybean (Glycine max (L.) Merr.) has seldom been reported as a natural host of AMV and there are limited reports of detection of AMV in field-grown soybean plants (4). However, AMV incidence in soybean fields in the midwestern United States has been on the rise in recent years, which is partly attributed to the introduction of the soybean aphid (Aphis glycines) (1,4). In June 2009, soybean plants of cv. Lee68 exhibiting moderate leaf distortion, mottling, and stunting were observed at the East Tennessee Research and Education Center. Leaf samples from 18 symptomatic plants were collected and the sap was extracted and analyzed by antigen-coated indirect ELISA (3) with polyclonal antibodies against AMV, Soybean mosaic virus (SMV), and Bean pod mottle virus (BPMV). None of the samples tested positive for BPMV, but all were found to be infected with SMV. Sap extract from 1 of 18 plants tested positive for AMV and SMV. Sap from this infected plant ground in 10 mM phosphate buffer, pH 7.0, was mechanically inoculated to Carborundum-dusted unifoliate leaves of PI96983, which contains the dominant Rsv1-locus conferring functional immunity to a majority of SMV strains (2). AMV, not SMV, was detected by ELISA in the systemically infected trifoliolate leaves that exhibited moderate mottling, mild leaf distortion, and stunting 14 days postinoculation. Sap was extracted from the infected tissues and the virus was passaged four times through PI96983 before being inoculated to Phaseolus vulgaris cv. Blue Lake. A local lesion isolate was obtained following three successive passages in this host and the isolate was propagated in soybean cv. Williams82. The biologically purified isolate was capable of infecting soybean cvs. L78-379 (Rsv1), L81-4420 (Rsv1), L29 (Rsv3), V94-5152 (Rsv4), Lee68, and Colfax upon sap inoculation. The infected plants exhibited a range of systemic symptoms including mottling, leaf distortion, necrosis, chlorosis, and moderate stunting. To characterize the virus further, total RNA was extracted from infected Williams82 leaf tissues with the RNeasy Plant Mini Kit (Qiagen, Valencia, CA). The RNA served as a template for cDNA synthesis in the presence of random primers. The resultant cDNA served as a template in a PCR assay with primers 1193 (forward) (5'-AGCTGAATTCATGAGTTCTTCACAAC-3') and 1858 (reverse) (5'-GCTAGCGGCCGCTCAATGACGATC-3') corresponding to nucleotides 1,193 to 1,210 and 1,858 to 1,840 of RNA3 from AMV-Kr (GenBank Accession No. AB126032), respectively. The amplified fragments were purified and directly sequenced bidirectionally using the same primers. BLAST analysis of the resultant nucleotide sequences showed 98% identity to an AMV isolate from a naturally infected soybean plant in Illinois (GenBank Accession No. HQ185569), and 97% identity to an isolate described from P. vulgaris in the United States (GenBank Accession No. AY340070.1). To our knowledge, this is the first report of natural infection of soybean by AMV in Tennessee. References: (1) J. Bol. Mol. Plant Pathol. 4:1, 2003. (2) M. R. Hajimorad and J. H. Hill. Mol. Plant-Microbe Interact. 14:587, 2001. (3) M. Malapi-Nelson et al. Plant Dis. 93:1259, 2009. (4) E. E. Mueller and C. R. Grau. Plant Dis. 91:266, 2007.

19.
Zhonghua Wei Chang Wai Ke Za Zhi ; 23(3): 230-236, 2020 Mar 25.
Artigo em Zh | MEDLINE | ID: mdl-32192300

RESUMO

In 2004, Habr-Gama reported a new group of rectal cancer patients achieving clinical complete response (cCR) after neoadjuvant chemoradiotherapy, who were able to get a satisfactory curative effect after a non-operative watch and wait (W&W) strategy. Since then, W&W has attracted more and more public attention. Although results of accumulating clinical studies have shown that W&W strategy is feasible for treating part of rectal cancer patients, there is still a lack of evidence-based medical evidence. Therefore, the feasibility and safety of the strategy still need further investigation. The main focuses are on the optimized scheme of chemoradiotherapy, the timing and standard to evaluate a cCR, and the shortage of a more precise approach to judging and predicting cCR. Whether a salvage surgery is safe and feasible for local regeneration, the risk of increasing distant metastasis and long-term oncologic and functional outcomes of patients also remain uncertain. Based on the literature and the institute's experience, this paper will elaborate the current development status and existing problems of W&W and look forward to the application prospect and future challenges.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Quimiorradioterapia , Humanos , Recidiva Local de Neoplasia , Neoplasias Retais/terapia , Resultado do Tratamento , Conduta Expectante
20.
Arch Virol ; 154(12): 1909-16, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19838620

RESUMO

Triple gene block 1 (TGB1) and coat protein (CP) sequences of 30 hosta virus X (HVX) isolates from Tennessee (TN), USA, were determined and compared with available sequences in GenBank. The CPs of all known HVX isolates, including those from TN, shared 98.3-100% and 98.2-100% nucleotide and amino acid sequence identity, respectively, whereas TGB1 shared 97.4-100% nucleotide and 97-100% amino acid sequence identity. TGB1 of TN isolates were all longer by one codon from that of a Korean isolate, which is the only sequence publicly available. Phylogenetic analysis of nucleotide and amino acid sequences of TGB1 and CP of all known HVX isolates, separately or combined, revealed a close relationship, suggesting that all of them are derived from a common ancestor. Phylogenetic analysis with the type member of each genus of the family Flexiviridae confirmed that HVX is a member of a distinct species of the genus Potexvirus.


Assuntos
Variação Genética , Hosta/virologia , Filogenia , Doenças das Plantas/virologia , Potexvirus , Proteínas do Capsídeo/genética , Dados de Sequência Molecular , Potexvirus/classificação , Potexvirus/genética , Potexvirus/isolamento & purificação , Análise de Sequência de DNA , Especificidade da Espécie , Tennessee , Proteínas Virais/genética
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