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1.
Front Plant Sci ; 14: 1276055, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38078117

RESUMO

Sclerotinia sclerotiorum (Lib.) de Bary is a highly destructive fungal pathogen that seriously damages the yield and quality of Brassica napus worldwide. The complex interaction between the B. napus and S. sclerotiorum system has presented significant challenges in researching rapeseed defense strategies. Here, we focus on the infection process of S. sclerotiorum, the defense mechanisms of rapeseed, and recent research progress in this system. The response of rapeseed to S. sclerotiorum is multifaceted; this review aims to provide a theoretical basis for rapeseed defense strategies.

2.
Huan Jing Ke Xue ; 43(7): 3575-3586, 2022 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-35791541

RESUMO

Clear vertical variations in phytoplankton community structure are usually observed in deep-water lakes and reservoirs, which is one of the key components of water quality and ecosystem functioning. However, the vertical patterns and ecological drivers of phytoplankton communities in deep-water lakes and reservoirs are still understudied. In this study, we took Qiandao Lake, a deep-water reservoir, as an example to reveal the vertical distribution characteristics of phytoplankton communities and its influencing factors by investigating phytoplankton community structure and the associated water quality index at 12 sites across the whole lake in two seasons (spring and autumn). The results showed that the phytoplankton abundance and chlorophyll a were highest in the surface layer in autumn and then decreased toward deep water, whereas in spring, the maximum value occurred in the subsurface layer (2-5 m), and the dominant phytoplankton species showed obvious vertical stratification characteristics. Specifically, in spring, Cryptomonas and Pseudanabaena dominated the surface and subsurface layers, Cryptomonas dominated in the middle layer, and the abundance of Cyclotella at the bottom layer was significantly higher than that of the other algae genera. The dominant genera in autumn were Pseudanabaena and Aphanizomenon. In the subsurface and middle layers, Leptolyngbya and Pseudanabaena occupied the dominant position, and Leptolyngbya became the only dominant genus. In the bottom layer, Leptolyngbya was the only dominant genus. The key environmental indicators of the water also had obvious vertical changes. The contents of N and P nutrients had a negative correlation with the water depth in spring, whereas the reverse trend was observed in autumn. The correlation analysis showed that the vertical variation in phytoplankton abundance in spring was significantly positively correlated with phosphate concentration, whereas the vertical distribution of phytoplankton abundance in autumn was significantly positively correlated with intensity of light, and the water temperature, NH4+-N, and total nitrogen were the main factors driving the vertical changes in the dominant genera of phytoplankton community in the two seasons. To summarize, environmental conditions such as water temperature, light, and nutrients had strong effects on the vertical distribution of phytoplankton. In the ecological investigation and quality assessment of deep-water lakes and reservoirs, the vertical distribution characteristics of the phytoplankton community structure and the influence of environmental conditions should be fully considered.


Assuntos
Lagos , Fitoplâncton , Clorofila A , Ecossistema , Estações do Ano
3.
Lab Invest ; 86(12): 1261-71, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17075582

RESUMO

The aims of this study were to use computerized morphometry in order to differentiate between the degree of dysplasia and to predict progression to invasive adenocarcinoma in Barrett's esophagus (BE). Biopsies from 97 patients with BE graded by a consensus forum of expert gastrointestinal pathologists were available for morphometrical analysis. The study group included 36 biopsies negative for dysplasia (ND), none of which progressed to carcinoma; 16 indefinite for dysplasia (IND) and 21 low-grade dysplasia (LGD), of which three progressed in each group and 24 high-grade dysplasia (HGD), of which 15 progressed to invasive carcinoma. Computerized morphometry was used for measuring indices of size, shape, texture, symmetry and architectural distribution of the epithelial nuclei. Low-grade dysplasia was best differentiated from the ND group by nuclear pseudostratification (P=0.036), pleomorphism (P<0.01), and chromatin texture (margination, P<0.01) and from the HGD group by nuclear area (P<0.01), pleomorphism (P<0.01), chromatin texture (margination, P<0.01), symmetry (P<0.01), and orientation (P=0.027). These results were validated on a new set of cases (n=55) using a neural network model, resulting in an accuracy of 89% for differentiating between the ND and LGD groups and 86% for differentiating between the LGD and HGD groups. Within the HGD group, univariate significant predictors of the progression interval to carcinoma were: indices of nuclear texture (heterogeneity: P=0.0019, s.d.-OD: P=0.005) and orientation: P=0.022. Nuclear texture (heterogeneity) was the only independent predictor of progression (P=0.004, hazard=11.54) by Cox's multivariate test. This study proposes that computerized morphometry is a valid tool for determining the grade of dysplasia in BE. Moreover, histomorphometric quantification of nuclear texture is a powerful tool for predicting progression to invasive adenocarcinoma in patients with HGD.


Assuntos
Adenocarcinoma/etiologia , Esôfago de Barrett/patologia , Neoplasias Esofágicas/etiologia , Interpretação de Imagem Assistida por Computador/métodos , Lesões Pré-Cancerosas/patologia , Humanos , Redes Neurais de Computação
4.
Emerg Infect Dis ; 12(9): 1353-60, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17073083

RESUMO

Position-specific entropy profiles created from scanning 306 human and 95 avian influenza A viral genomes showed that 228 of 4591 amino acid residues yielded significant differences between these 2 viruses. We subsequently used 15,785 protein sequences from the National Center for Biotechnology Information (NCBI) to assess the robustness of these signatures and obtained 52 "species-associated" positions. Specific mutations on those points may enable an avian influenza virus to become a human virus. Many of these signatures are found in NP, PA, and PB2 genes (viral ribonucleoproteins [RNPs]) and are mostly located in the functional domains related to RNP-RNP interactions that are important for viral replication. Upon inspecting 21 human-isolated avian influenza viral genomes from NCBI, we found 19 that exhibited > or =1 species-associated residue changes; 7 of them contained > or =2 substitutions. Histograms based on pairwise sequence comparison showed that NP disjointed most between human and avian influenza viruses, followed by PA and PB2.


Assuntos
Sequência de Aminoácidos , Genoma Viral , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Influenza Aviária/virologia , Influenza Humana/virologia , Animais , Aves/virologia , Humanos , Virus da Influenza A Subtipo H5N1/classificação , Virus da Influenza A Subtipo H5N1/genética , Vírus da Influenza A Subtipo H7N7/classificação , Vírus da Influenza A Subtipo H7N7/genética , Vírus da Influenza A Subtipo H9N2/classificação , Vírus da Influenza A Subtipo H9N2/genética , Dados de Sequência Molecular , Mutação , Análise de Sequência de DNA , Especificidade da Espécie , Proteínas Virais/genética
5.
Di Yi Jun Yi Da Xue Xue Bao ; 24(12): 1434-6, 2004 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-15604080

RESUMO

OBJECTIVE: To investigate the effects of insulin on the expression of whole-blood platelet membrane P-selectin. METHODS: Flow cytometry (FCM) was used to detect the expression of whole-blood platelet membrane P-selectin, and the effect of insulin on the expression on quiescent and activated plasma platelet observed in normal young subjects. RESULTS: Insulin had no effect on the P-selectin expression on quiescent platelet membrane, but significantly inhibited the up-regulation of P-selectin expression induced by thrombin and collagen respectively, exhibiting dose- and time-dependent effects. CONCLUSION: Insulin can inhibit P-selectin expression on activated platelet membrane.


Assuntos
Plaquetas/metabolismo , Membrana Celular/metabolismo , Insulina/farmacologia , Selectina-P/biossíntese , Adolescente , Adulto , Depressão Química , Feminino , Humanos , Masculino , Selectina-P/genética , Ativação Plaquetária
6.
Di Yi Jun Yi Da Xue Xue Bao ; 23(9): 943-5, 2003 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-13129728

RESUMO

OBJECTIVE: To investigate the effects of insulin on the expression of platelet membrane glycoprotein (GP) IIb/III a and its mechanism in normal subjects. METHODS: Flow cytometry was used to detect the expression of the whole-blood platelet membrane GP b/ a. The respective effects of insulin, L-nitro-arginine methyl ester (L-NAME) and methylene blue (MB) and their combination on the expression of GP b/ a were also studied. RESULTS: Insulin had no effect on the expression of GP II b/III a in healthy subjects, but significantly inhibited the up-regulated expression of GP II b/III a induced respectively by thrombin and collagen. The inhibitory effects of insulin on thrombin- or collagen-induced expression of platelet membrane GP II b/III a were dose- and time-dependent, and could be completely blocked by L-NAME or methylene blue. CONCLUSION: Insulin may inhibit the over-expression of platelet membrane GP IIb/III a by NOS-->NO-->GC-->GMP pathway.


Assuntos
Insulina/farmacologia , Integrina beta3/sangue , Glicoproteína IIb da Membrana de Plaquetas/sangue , Adolescente , Adulto , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Azul de Metileno/farmacologia , NG-Nitroarginina Metil Éster/farmacologia
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