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991.
Verticillium wilt is a vascular disease of cotton. The causal fungus, Verticillium dahliae, secretes elicitors in culture. We have generated ~1,000 5′-terminal expressed sequence tags (ESTs) from a cultured mycelium of V. dahliae. A number of ESTs were found to encode proteins harboring putative signal peptides for secretion, and their cDNAs were isolated. Heterologous expression led to the identification of a protein with elicitor activities. This protein, named V. dahliae necrosis- and ethylene-inducing protein (VdNEP), is composed of 233 amino acids and has high sequence identities with fungal necrosis- and ethylene-inducing proteins. Infiltration of the bacterially expressed His-VdNEP into Nicotiana benthamiana leaves resulted in necrotic lesion formation. In Arabidopsis thaliana, the fusion protein also triggered production of reactive oxygen species and induced the expression of PR genes. When added into suspension cultured cells of cotton (Gossypium arboreum), the fusion protein elicited the biosynthesis of gossypol and related sesquiterpene phytoalexins at low concentrations, and it induced cell death at higher concentrations. On cotton cotyledons and leaves, His-VdNEP induced dehydration and wilting, similar to symptoms caused by a crude preparation of V. dahliae elicitors. Northern blotting showed a low level of VdNEP expression in the mycelium during culture. These data suggest that VdNEP is a wilt-inducing factor and that it participates in cotton-V. dahliae interactions.  相似文献   
992.
The photosynthetic performance and related leaf traits of Incarvillea delavayi Bur. et Franch were studied at different water regimes to assess its capacity for photosynthetic acclimation to water stress. The initial response of I. delavayi to water stress was the closure of stomata, which resulted in down-regulation of photosynthesis. The stomatal limitation (SL) represented the main component to photosynthetic limitations but non-stomatal limitation (NSL) increased quickly with the increasing water stress, and had similar magnitude to SL under severe water stress (soil moisture 25–30 % of field capacity). Chlorophyll (Chl) a fluorescence parameters characterizing photosystem (PS) 2 photochemical efficiency (ΦPS2), electron transport rate (J) and photochemical quenching (qP) decreased with the increasing water stress, indicating impaired photosynthetic apparatus. However, the water-stressed plants had a increased mesophyll CO2 diffusional conductance, Chl a/b ratio, leaf nitrogen partitioning in RuBPCO and bioenergetics in later grown parts, indicating that I. delavay had a substantial physiological plasticity and showed a good tolerance to water stress.  相似文献   
993.
Journal of Plant Growth Regulation - Destruction caused by plant diseases is terrible. Mexican lime witches' broom (MLWB) is a phytoplasma disease, which has caused considerable damage...  相似文献   
994.
Single nucleotide polymorphism (SNP) array and karyotype analyses were conducted on 441 spontaneous miscarriage placental villous tissues collected from women from southern China. Subsequently, the results from these two analyses were compared to evaluate the best diagnostic strategy for subsequent pre-pregnancy planning. Here, the success rate of genetic testing using karyotyping and SNP array analysis was 78.46% (346/441) and 100.0% (441/441), respectively. The abnormality rate estimated by both methods was 54.9% (242/441). Three hundred and forty-six cases were successfully detected via both SNP array and karyotype analyses; the rate of consistent detection was 96.24% (333/346), whereas 13 cases were not consistent. There was no substantial positive correlation between age and genetic abnormalities such as Turner syndrome, structural variation or euploidy state in the different age groups studied. However, the aneuploidy rate was significantly different in each age group. Thus, although SNP array has higher success rate and resolution in genetic abnormality detection, supplementary karyotype analysis is needed for a more accurate revelation of the genetic aetiology of miscarriages. Therefore, this study indicates that simultaneous karyotype and SNP array analyses should be performed for spontaneous miscarriages. Furthermore, miscarriages irrespective of maternal age must be genetically analysed.  相似文献   
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Osteoarthritis (OA) is a common joint disease that mainly affects the diarthrodial joints. Treatments for OA include non-pharmacological interventions, topical and oral therapies, intra-articular therapies and joint surgery. However, all the treatments mentioned above mainly aim to control the symptoms instead of improving or reversing the joint condition. In this research, we observed the effect of recombinant platelet-derived growth factor (PDGF)-BB on OA in a monosodium iodoacetate (MIA)–induced rat model and revealed the possible mechanisms. In vitro, the level of inflammation in the chondrocytes was gradually alleviated, and the apoptosis rate was gradually decreased by PDGF-BB at increasing concentrations. The levels of p-p38, Bax and caspase-3 decreased, and the level of p-Erk increased with increasing PDGF-BB concentration. In vivo, PDGF-BB could significantly reverse chondrocyte and matrix loss. Furthermore, high concentrations of PDGF-BB could alleviate cartilage hyperplasia to remodel the tissue. The level of collagen II was up-regulated, and the levels of collagen X and apoptosis were down-regulated by increasing concentrations of PDGF-BB. In conclusion, recombinant PDGF-BB alleviated OA by down-regulating caspase-3-dependent apoptosis. The effects of PDGF-BB on OA mainly include inhibiting chondrocyte loss, reducing cartilage hyperplasia and osteophyte formation, and regulating collagen anabolism.  相似文献   
998.
Oridonin, a natural diterpenoid compound extracted from a Chinese herb, has been proved to exert anti-oxidative stress effects in various disease models. The aim of the present study was to investigate the protective effects of oridonin on oxidative stress-induced endothelial injury in ischaemic stroke. We found oridonin repaired blood-brain barrier (BBB) integrity presented with upregulation of tight junction proteins (TJ proteins) expression, inhibited the infiltration of periphery inflammatory cells and neuroinflammation and thereby reduced infarct volume in ischaemic stroke mice. Furthermore, our results showed that oridonin could protect against oxidative stress-induced endothelial injury via promoting nuclear translocation of nuclear factor-erythroid 2 related factor 2 (Nrf-2). The specific mechanism could be the activation of AKT(Ser473)/GSK3β(Ser9)/Fyn signalling pathway. Our findings revealed the therapeutic effect and mechanism of oridonin in ischaemic stroke, which provided fundamental evidence for developing the extracted compound of Chinese herbal medicine into an innovative drug for ischaemic stroke treatment.  相似文献   
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Background: Vaccination is an important preventative measure against the coronavirus disease 19 (COVID-19) pandemic. To implement vaccination and immunization programs effectively, it is essential to investigate public attitudes toward COVID-19 vaccines. This study examined the attitudes of Chinese college students toward COVID-19 vaccines and their associated factors. Methods: A cross-sectional study was conducted in college students nationwide from December 27, 2020 to January 18, 2021. Attitudes toward COVID-19 vaccines and acceptance of future vaccination programs were assessed. Results: Totally, 2,881 college students participated in this survey; of them, 76.3% (95% CI: 74.8% - 77.9%) were willing to accept a COVID-19 vaccine in the future. Multiple logistic analysis revealed that students living in urban (OR=1.409, 95% CI: 1.152 - 1.724, p=0.001) and those studying health-related courses (OR=1.581, 95% CI: 1.291 - 1.935, p<0.001) were more likely to have a positive attitude toward COVID-19 vaccines. In addition, those who were worried about being infected with COVID-19 (very much vs no, OR=1.690, 95% CI: 1.212-2.356, p=0.002), heard previously about COVID-19 vaccines (OR=1.659, 95% CI: 1.268-2.170, p<0.001), believed that vaccines are safe (Yes vs No, OR=3.570, 95% CI: 1.825-6.980), thought that vaccines can protect people from being infected with COVID-19 (Yes vs No, OR=1.957, 95% CI: 1.286-2.979, p=0.002), and had encouraged their family and friends to have a vaccine (Yes vs No, OR=17.745, 95% CI: 12.271-25.660, p<0.001) had higher acceptance of COVID-19 vaccination. Conclusions: A high rate of acceptance of COVID-19 vaccines was found among Chinese college students. However, vaccine uptake may be reduced by concerns about vaccine safety and efficacy. Alleviating these concerns and enhancing public confidence in vaccines are crucial for future immunization programs against the COVID-19 pandemic.  相似文献   
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