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1.
Plant Dis ; 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38035788

RESUMO

Hypericum chinensis is growing in popularity amongst consumers in cut-flower and pop-flower market as an ornamental woody plant for its florid berry and colorful flower. In August 2019, a new leaf spot disease was observed on H. chinensis in three commercial nurseries in Kunming (25°05'N, 102°72'E), Yunnian province, China. Disease symptoms were observed on approximately 40% of the plants one year after planting and 30% of the leaves were infected. Leaf symptoms began as small, water-soaked lesions on young leaves which later became larger, dark brown and necrotic. The lesion size ranged from 0.2 to 2.8 cm in diameter. For pathogen isolation, three samples of symptomatic leaves were collected from four different nurseries. The leaves were cut into 0.5 mm pieces, surface sterilized using 70% ethanol for 30 s, and 3% NaOCl for 5 min, rinsed three times in sterilized distilled water and plated on potato dextrose agar (PDA) (Zhou et al. 2023). The plates were incubated at 26°C in the dark for 3 days. Eight isolates with comparable morphological characteristics were obtained. Initially, colonies produced pale gray to white aerial mycelia, turning dark gray after 5 days. The isolates produced hyaline, single celled, straight and cylindrical conidia, with mean size 9.7 to 14.8 µm long × 3.7 to 5.6 µm wide (n = 100). Morphological characteristics were consistent with Colletotrichum sp. (Bailey and Jeger 1992). For molecular analysis, genomic DNA was extracted from three representative isolates (XSD1, XSD3 and XSD5), amplified using the primers ITS1/ITS4 (Yin et al. 2012) and T1/Bt2b (Glass and Donaldson 1995) and submitted to sequencing (Weir et al. 2012). DNA sequences of the isolates XSD2, XSD3 and XSD8 were identical. DNA sequences of a representative isolate XSD2 were deposited in GenBank (accession no. MW202334 for ITS, and OR347007 for TUB 2). MegaBLAST analysis of the ITS and TUB2 sequences showed 99.5% and 99.3% similarity with C. kahawae strain ICMP 18539 (accession no. NR_120138.1 for ITS) and strain IMI319418 (JX145227.1 for TUB 2). Pathogenicity tests were conducted by inoculating the pathogen on healthy mature leaves of H. chinensis in the field. Ten leaves (two leaves/plant) were inoculated by spraying conidial suspension (106 spores/ml) of isolates XSD1, XSD3 and XSD5, and covered with plastic bags to maintain high humidity for 48 hours, respectively. Leaves treated with sterile distilled water served as a control. All inoculated leaves showed symptoms similar to those observed in the field at 23±5°C 10 days after inoculation. No symptoms developed on non-inoculated leaves. The pathogen was re-isolated from inoculated diseased leaves and identified as C. kahawae based on morphological and molecular characters. C. kahawae has been reported to cause leaf spot on cultivated rocket in Italy (Garibaldi et al. 2016), and anthracnose disease on tree tomato in Colombia (Rojas et al. 2018), to our knowledge, this is the first report of C. kahawae causing anthracnose on H. chinensis worldwide. Due to important ornamental and economic value of H. chinensis, the distribution of C. kahawae needs to be investigated and monitored for effective disease management strategies to be developed.

2.
BMC Genomics ; 23(1): 278, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35392815

RESUMO

BACKGROUND: Rice sheath blight, caused by Rhizoctonia solani Kühn (teleomorph: Thanatephorus cucumeris), is one of the most severe diseases in rice (Oryza sativa L.) worldwide. Studies on resistance genes and resistance mechanisms of rice sheath blight have mainly focused on indica rice. Rice sheath blight is a growing threat to rice production with the increasing planting area of japonica rice in Northeast China, and it is therefore essential to explore the mechanism of sheath blight resistance in this rice subspecies. RESULTS: In this study, RNA-seq technology was used to analyse the gene expression changes of leaf sheath at 12, 24, 36, 48, and 72 h after inoculation of the resistant cultivar 'Shennong 9819' and susceptible cultivar 'Koshihikari' with R. solani. In the early stage of R. solani infection of rice leaf sheaths, the number of differentially expressed genes (DEGs) in the inoculated leaf sheaths of resistant and susceptible cultivars showed different regularity. After inoculation, the number of DEGs in the resistant cultivar fluctuated, while the number of DEGs in the susceptible cultivar increased first and then decreased. In addition, the number of DEGs in the susceptible cultivar was always higher than that in the resistant cultivar. After inoculation with R. solani, the overall transcriptome changes corresponding to multiple biological processes, molecular functions, and cell components were observed in both resistant and susceptible cultivars. These included metabolic process, stimulus response, biological regulation, catalytic activity, binding and membrane, and they were differentially regulated. The phenylalanine metabolic pathway; tropane, piperidine, and pyridine alkaloid biosynthesis pathways; and plant hormone signal transduction were significantly enriched in the early stage of inoculation of the resistant cultivar Shennong 9819, but not in the susceptible cultivar Koshihikari. This indicates that the response of the resistant cultivar Shennong 9819 to pathogen stress was faster than that of the susceptible cultivar. The expression of plant defense response marker PR1b gene, transcription factor OsWRKY30 and OsPAL1 and OsPAL6 genes that induce plant resistance were upregulated in the resistant cultivar. These data suggest that in the early stage of rice infection by R. solani, there is a pathogen-induced defence system in resistant rice cultivars, involving the expression of PR genes, key transcription factors, PAL genes, and the enrichment of defence-related pathways. CONCLUSION: The transcriptome data revealed the molecular and biochemical differences between resistant and susceptible cultivars of rice after inoculation with R. solani, indicating that resistant cultivars have an immune response mechanism in the early stage of pathogen infection. Disease resistance is related to the overexpression of PR genes, key transcriptome factors, and PAL genes, which are potential targets for crop improvement.


Assuntos
Oryza , Oryza/metabolismo , Doenças das Plantas/genética , Rhizoctonia/genética , Fatores de Transcrição/metabolismo , Transcriptoma
3.
Plant Dis ; 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35640954

RESUMO

Geranium wilfordii Maxim. is a weed of perennial herbs and considerable medicinal plant for treating acute and chronic rheumatalgia in China. In August 2019, leaf spots on G. wilfordii were observed in Harbin (45°60'N, 126°64'E), Heilongjiang Province, China. The disease occurred on 15 to 30% of G. wilfordii leaves in three nurseries (~1.5 ha/each nursery). Initial symptoms were brown necrotic spots with a gray-white center, which enlarged gradually from approximately 1 to 5 mm in diameter, and produced concentric rings and became necrotic. Twelve infected tissues from twelve diseased leaves were surface disinfested in 0.5% NaOCl for 5 min, rinsed three times in sterile distilled water, dried on sterilized filter paper and cultured on potato dextrose agar (PDA) amended with 50 µg/ml streptomycin at 26°C for 5 days. Eight fungal cultures with consistent characteristics were obtained and subcultured by transferring hyphal tips onto fresh PDA. Single-conidium isolates were generated with methods reported previously (Leslie and Summerell 2006). Colonies on PDA consisted of cottony, dense, grayish white mycelium, pale gray colony. Conidia of a representative isolate LGC2 were single-celled, hyaline, cylindrical to slightly curved with a rounded apex and truncated base that measured 16.2 to 22.5 µm (length) × 2.6 to 3.7 µm (width) (n = 50). The appressoria were elliptic to claviform or slightly lobed on synthetic nutrient-poor agar. Based on these characteristics, the eight isolates were identified as Colletotrichum dematium (Damm et al. 2009). Genomic DNA was extracted from representative isolates LGC2, LGC3, LGC5 and the internal transcribed spacer regions (ITS),beta-tubulin (TUB2) and actin (ACT) were amplified and sequenced using the primers ITS1/ITS4 (Yin et al. 2012), T1/Bt2b (Glass and Donaldson 1995) and ACT-512F/ACT-783R (Carbone and Kohn 1999), respectively. DNA sequences of isolates LGC2, LGC3, and LGC5 were identical and deposited onto the GenBank (accession nos. MW193053.1 for ITS, MZ357349.1 for TUB2, and OL956946.1 for ACT). MegaBLAST analysis showed 100%, 99.7% and 100% identical to C. dematium isolates CBS 125.25 (accession nos. NR_111453.1 for ITS 552/553 bp, GU228113.1 for TUB2 386/387 bp, and GU227917.1 for ACT 231/231 bp respectively. A pathogenicity test was performed on with a representative isolate LGC2 by spraying spore suspension (1 × 106 conidia/ml) on the surfaces of all leaves of ten healthy three-month-old G. wilfordii plants. All leaves of ten control plants were inoculated with sterile water to serve as the control. All plants were placed in a humidity chamber (>95% RH, 26℃) for 48 h after inoculation and then transfered in a greenhouse at 22/28°C with a 12:12h light-dark cycle for 10 days. All inoculated leaves showed symptoms similar to those observed in the fields, while no symptoms were observed on the control leaves. The experiment was conducted twice. The fungus was re-isolated from the infected leaves and confirmed to be C. dematium according to morphological and molecular characteristics. C. dematium has previously been reported on common knotgrass (Liu et al. 2016), on piper betle (Sun et al. 2020), peanut anthracnose in China (Yu et al. 2020). To our knowledge, this is the first report of C. dematium causing G. wilfordii anthracnose in China. G. wilfordii anthracnose caused by C. dematium poses a threat to significantly reduce the quality of G. wilfordii. Therefore, its distribution needs to be investigated and effective disease management strategies developed.

4.
BMC Plant Biol ; 21(1): 588, 2021 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-34895144

RESUMO

BACKGROUND: Frogeye leaf spot (FLS) is a destructive fungal disease that affects soybean production. The most economical and effective strategy to control FLS is the use of resistant cultivars. However, the use of a limited number of resistant loci in FLS management will be countered by the emergence of new high-virulence Cercospora sojina races. Therefore, we identified quantitative trait loci (QTL) that control resistance to FLS and identified novel resistant genes using a genome-wide association study (GWAS) on 234 Chinese soybean cultivars. RESULTS: A total of 30,890 single nucleotide polymorphism (SNP) markers were used to estimate linkage disequilibrium (LD) and population structure. The GWAS results showed four loci (p < 0.0001) distributed over chromosomes (Chr.) 5 and 20, that are significantly associated with FLS resistance. No previous studies have reported resistance loci in these regions. Subsequently, 45 genes in the two resistance-related haplotype blocks were annotated. Among them, Glyma20g31630 encoding pyruvate dehydrogenase (PDH), Glyma05g28980, which encodes mitogen-activated protein kinase 7 (MPK7), and Glyma20g31510, Glyma20g31520 encoding calcium-dependent protein kinase 4 (CDPK4) in the haplotype blocks deserves special attention. CONCLUSIONS: This study showed that GWAS can be employed as an effective strategy for identifying disease resistance traits in soybean and narrowing SNPs and candidate genes. The prediction of candidate genes in the haplotype blocks identified by disease resistance loci can provide a useful reference to study systemic disease resistance.


Assuntos
Cercospora/patogenicidade , Resistência à Doença/genética , Glycine max/genética , Doenças das Plantas/imunologia , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Estudo de Associação Genômica Ampla , Genótipo , Haplótipos , Modelos Lineares , Desequilíbrio de Ligação , Fenótipo , Doenças das Plantas/microbiologia , Glycine max/imunologia , Glycine max/microbiologia , Virulência
5.
Plant Dis ; 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33728961

RESUMO

Corn (Zea mays L.) stalk rot, caused by various pathogens, is one of the most prevalent corn diseases worldwide. In October 2019, a survey was carried out to determine pathogenic fungi causing corn stalk rot in 3 fields (~120 ha) in Harbin city (44.04°N 125.42°E), Heilongjiang Province, China. In each field, 100 plants at 5 sampling points were assessed at the milk stage (R3) of development. Disease incidence was 12%. Symptomatic plants showed rapid death of the upper leaves, drooping ears and stalks were soft, hollow, watersoaked with white hyphae present on teh outside of the stalk. Pieces of tissue (0.25 cm2) from 15 individual diseased stalks (5 plants/field) were surface disinfested in 0.5% NaOCl for 5 min, rinsed three times in sterile distilled water and cultured on potato dextrose agar (PDA) containing streptomycin (50 µg/mL). After three days of incubation, a total of twelve fungal cultures with uniform characteristics were isolated and subcultured by transferring hyphal tips onto V8. Colonies on V8 selective medium were creamy white and floccus, with a growth rate of 20 mm/day at 26°C in darkness. Oospores were mostly plerotic, and oogonia walls were 1.3 to 2.7 µm thick (n = 50); globose oogonia, 23.9 to 30.5 µm in diameter (n = 50), and had 1 to 8 antheridia. Based on these characteristics, the isolates were identified as Pythium sp. (van der Plaats-Niterink 1981). Genomic DNA was extracted from single conidial cultures of representative isolates (MZYJF1, MZYJF3 and MZYJF7), and the internal transcribed spacer (ITS) region and cytochrome coxidase subunit II (CoxII) gene were amplified and sequenced using the primers ITS1/ITS4 (Yin et al. 2012) and COX2f/COX2r (Hudspeth et al. 2000), respectively. Partial nucleotide sequences of 796 bp and 573 bp for the ITS and COX11 amplicons, respectively, were obtained and deposited in GenBank (accession no. MW447501 for ITS, and MW471006 for COXII). MegaBLAST analysis of the ITS and CoxII sequences of MZYJF1 isolate showed 100% similarity with sequences from P. aristosporum strain ATCC 11101. The isolates were identified as P. aristosporum based on the fact that P. aristosporum has aplerotic oospores and less antheridia per oogonium than P. arrhenomanes (van der Plaats-Niterink 1981). A pathogenicity test was performed on corn cv. Xianyu 335 at tasseling stage (VT) in the field. An oospore suspension, obtained from isolate MZYJF1 grown on V8 agar media for 4 weeks (Green and Jensen, 2000) and diluted to 1×104 oospores/mL using blood cell counting method, was injected into the base of the maize stems of 6 healthy plants (1.5 ml/plant ) using a syringe. Control plants were injected with distilled sterile water. All inoculated plants showed symptoms 25 days after inoculation that were similar to those observed in the field. The oomycete of P. aristosporum was reisolated from symptomatic plants on V8 agar media and identified according to morphological and molecular characteristics. No symptoms were observed on the control plants. P. aristosporum has previously been reported on causing damping-off of pea in the Columbia basin of Central Washington (Alcala et al. 2016) and on soybean in North Dakota (Zitnick-Anderson and Nelson 2015). To our knowledge, this is the first report of P. aristosporum causing corn stalk rot in China. Corn stalk rot caused by P. aristosporum poses a threat to significantly reduce the quality of corn. Thus, its distribution needs to be investigated and effective disease management strategies developed.

6.
BMC Genomics ; 21(1): 172, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075575

RESUMO

BACKGROUND: Recently, a new strain of Cercospora sojina (Race15) has been identified, which has caused the breakdown of resistance in most soybean cultivars in China. Despite this serious yield reduction, little is known about why this strain is more virulent than others. Therefore, we sequenced the Race15 genome and compared it to the Race1 genome sequence, as its virulence is significantly lower. We then re-sequenced 30 isolates of C. sojina from different regions to identifying differential virulence genes using genome-wide association analysis (GWAS). RESULTS: The 40.12-Mb Race15 genome encodes 12,607 predicated genes and contains large numbers of gene clusters that have annotations in 11 different common databases. Comparative genomics revealed that although these two genomes had a large number of homologous genes, their genome structures have evolved to introduce 245 specific genes. The most important 5 candidate virulence genes were located on Contig 3 and Contig 1 and were mainly related to the regulation of metabolic mechanisms and the biosynthesis of bioactive metabolites, thereby putatively affecting fungi self-toxicity and reducing host resistance. Our study provides insight into the genomic basis of C. sojina pathogenicity and its infection mechanism, enabling future studies of this disease. CONCLUSIONS: Via GWAS, we identified five candidate genes using three different methods, and these candidate genes are speculated to be related to metabolic mechanisms and the biosynthesis of bioactive metabolites. Meanwhile, Race15 specific genes may be linked with high virulence. The genes highly prevalent in virulent isolates should also be proposed as candidates, even though they were not found in our SNP analysis. Future work should focus on using a larger sample size to confirm and refine candidate gene identifications and should study the functional roles of these candidates, in order to investigate their potential roles in C. sojina pathogenicity.


Assuntos
Ascomicetos/genética , Proteínas Fúngicas/genética , Glycine max/microbiologia , Polimorfismo de Nucleotídeo Único , Virulência/genética , Ascomicetos/patogenicidade , Estudo de Associação Genômica Ampla , Genômica , Micoses , Doenças das Plantas
7.
BMC Microbiol ; 20(1): 166, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546122

RESUMO

BACKGROUND: Cercospora sojina is a fungal pathogen that causes frogeye leaf spot in soybean-producing regions, leading to severe yield losses worldwide. It exhibits variations in virulence due to race differentiation between strains. However, the candidate virulence-related genes are unknown because the infection process is slow, making it difficult to collect transcriptome samples. RESULTS: In this study, virulence-related differentially expressed genes (DEGs) were obtained from the highly virulent Race 15 strain and mildly virulent Race1 strain under nitrogen starvation stress, which mimics the physiology of the pathogen during infection. Weighted gene co-expression network analysis (WGCNA) was then used to find co-expressed gene modules and assess the relationship between gene networks and phenotypes. Upon comparison of the transcriptomic differences in virulence between the strains, a total of 378 and 124 DEGs were upregulated, while 294 and 220 were downregulated in Race 1 and Race 15, respectively. Annotation of these DEGs revealed that many were associated with virulence differences, including scytalone dehydratase, 1,3,8-trihydroxynaphthalene reductase, and ß-1,3-glucanase. In addition, two modules highly correlated with the highly virulent strain Race 15 and 36 virulence-related DEGs were found to contain mostly ß-1,4-glucanase, ß-1,4-xylanas, and cellobiose dehydrogenase. CONCLUSIONS: These important nitrogen starvation-responsive DEGs are frequently involved in the synthesis of melanin, polyphosphate storage in the vacuole, lignocellulose degradation, and cellulose degradation during fungal development and differentiation. Transcriptome analysis indicated unique gene expression patterns, providing further insight into pathogenesis.


Assuntos
Cercospora/patogenicidade , Perfilação da Expressão Gênica/métodos , Nitrogênio/metabolismo , Fatores de Virulência/genética , Cercospora/classificação , Cercospora/genética , Cercospora/metabolismo , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Redes Reguladoras de Genes , Anotação de Sequência Molecular , Fenótipo , Análise de Sequência de RNA , Glycine max/microbiologia , Especificidade da Espécie , Estresse Fisiológico
8.
Langmuir ; 32(45): 11973-11979, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27762561

RESUMO

The ability to modulate amphiphilic aggregation reversibly with external stimuli, especially using light as a trigger, is of great importance. This has greatly contributed to the development of applications using self-assembly. However, most previously described systems are based on a specific molecular design and have shown difficultly in their application to light-inert aggregation. Here, we developed a general and effective approach to control the morphology of amphiphilic aggregates by light, which is suitable for different assemblies such as micelles, vesicles, and helixes. Our strategy is to construct a photoresponsive factor into light-inert self-assemblies. On the basis of the different capabilities to form host-guest inclusions between photoresponsive azobenzene sodium and light-inert molecules with cyclodextrin, the transformation of the corresponding amphiphilic aggregation can be controlled easily and reversibly by light stimuli. Not only the nanostructure of the aggregates but also the phase behavior, such as gel formation, can be modulated upon light irradiation using this method.

9.
Soft Matter ; 11(14): 2806-11, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25703770

RESUMO

Self-assemblies dominated by coordination interaction are hardly responsive to thermal stimuli. We show that in case the coordinating mode changes with temperature, the resultant assemblies also exhibit temperature dependence. The self-assemblies are constructed with perylene tetracarboxylate and metal ions. Compounds containing a perylene skeleton often self-assemble into micro-belts, which is also true for the combination of perylene tetracarboxylate and metal ions. However, a unique pinecone structure was observed upon increasing the temperature of the coordinating system. The structural transition is triggered by the change of coordinating mode between the carboxylate group and the metal ion. At low temperature, intermolecular coordination occurs which favours the growth of the coordinating self-assembly along the long axis of the perylene. However, upon the elevation of temperature, the coordination is overwhelmed by intra-molecular mode. This is against the extension of the coordinating assembly due to the loss of connection between neighbouring perylenes. As a result, the pinecone structure is observed. We expect that the cases introduced in this work may inspire the design of structurally controllable temperature-dependent soft materials based on coordinating self-assembly.

10.
Comput Intell Neurosci ; 2022: 1897298, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35592716

RESUMO

Although the competitive advantages brought by intelligent manufacturing technology for enterprises have been preliminarily shown, a lack of matched management capacity still greatly limits its effect. This paper focuses on the cost management capacity problem of intelligent manufacturing enterprises. The multiscale cost data model is established on the basis of the three-dimensional cost system model, which contains actual cost, standard cost, and testing cost. According to the scale transformation theory, we propose the dynamic updating mechanism of standard cost. The key cost center identification methods, respectively, for the production performance assessment scenario (KCCI_PPA) and the business decision-making scenario (KCCI_BDM) are also put forward, which could overcome the subjective determination limitation of initial observation scale in the traditional variable-scale data analysis method. Experiments with both industrial statistical and enterprise real datasets verify the efficiency and accuracy of the proposed KCCI_PPA and KCCI_BDM method.


Assuntos
Comércio , Análise de Dados , Indústrias , Inteligência , Tecnologia
11.
J Colloid Interface Sci ; 594: 727-736, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33789184

RESUMO

HYPOTHESIS: One of the main advances in double-chain surfactant systems has been their progress from the construction of assemblies to the transformation application in medicine and material science, especially to the drug delivery systems. Thus, it is critical to develop stimuli-responsive assemblies based on double-chain surfactants. We predicted that reversible assembly switching can be achieved by manipulation of the ternary host-guest competitive complexation among ß-cyclodextrin (ß-CD), surfactants, and designed azobenzene (Azo). EXPERIMENTS: In this work, Azo was introduced into vesicles using supramolecular assembly strategy. Vesicles are formed only when Azo moieties are in trans-form. UV switching of Azo groups led to fast disruption of the Azo@ß-CD complexes and relatively slow disintegration of the vesicles. With the alterative irradiation of UV and Vis light, the photoisomerization of azo group provokes the reversible disassembly and reassembly of vesicles. FINDINGS: This photo-responsive supramolecular strategy offered a controllable way to prepare responsive vesicles assembled from complex double-chain surfactants, such as phospholipids, which could be further used in drug delivery systems. This new perspective is instructive for the design and functional use of complex surfactants assembly. Importantly, the study results paved the way for the development of novel light-responsive assembly materials operating in aqueous media and biological field.

12.
CNS Drugs ; 34(8): 867-877, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32700191

RESUMO

BACKGROUND: Felbinac trometamol, an anti-inflammatory and analgesic drug, has been used to treat immediate postoperative pain. OBJECTIVE: The aim of this study was to evaluate the safety, tolerability, and pharmacokinetics of single or multiple intravenous infusions of felbinac trometamol in healthy Chinese volunteers. METHODS: A total of 56 healthy subjects were enrolled in a single-ascending dose study (11.78-377.00 mg), meanwhile 36 subjects were enrolled in a multiple-ascending dose study (47.13-188.50 mg). Safety endpoints included treatment-emergent adverse events, vital signs, electrocardiograms, and laboratory parameters. Pharmacokinetic endpoints included exposure of subjects to felblinac and metabolites of the drug in plasma, urine, and feces. RESULTS: Felblinac time to maximum plasma concentration was obtained at 0.5 h, corresponding to the end of the infusion. Maximum plasma concentration and area under the curve increased in a dose-dependent manner for felblinac and its metabolite, showing linear pharmacokinetic characteristics at single and multiple doses. After intravenous infusions of multiple doses three times (30 min each time) per day, the accumulation ratio of felblinac and its metabolite based on the area under the curve had a range of 1.34-1.45 and 1.60-1.87, respectively, across cohorts. After administration of the fourth dose, the plasma concentration of both felblinac and its metabolites was maintained at a steady state. Felbinac trometamol was well tolerated. Neither treatment-emergent adverse event frequency nor severity increased with increasing felbinac trometamol dose. CONCLUSIONS: Felbinac trometamol was well tolerated in our study. Based on the dose range in this study, 94.25 mg is the recommended target dose for a phase II study. CLINICAL TRIAL REGISTRATION: CTR20170496 and CTR20180896. The dates of registration are 2017-06-19 and 2018-07-02 ( https://www.chinadrugtrials.org.cn/ ).


Assuntos
Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/farmacocinética , Trometamina/efeitos adversos , Trometamina/farmacocinética , Administração Intravenosa/métodos , Adulto , Anti-Inflamatórios/administração & dosagem , Povo Asiático , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Masculino , Trometamina/administração & dosagem
13.
Nanoscale Adv ; 1(3): 1130-1135, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-36133206

RESUMO

High-quality graphene materials and high-performance graphene transistors have attracted much attention in recent years. To obtain high-performance graphene transistors, large single-crystal graphene is needed. The synthesis of large-domain-sized single-crystal graphene requires low nucleation density; this can lead to a lower growth rate. In this study, a Ni-foam assisted structure was developed to control the nucleation density and growth rate of graphene by tuning the flow dynamics. Lower nucleation density and high growth rate (∼50 µm min-1) were achieved with a 4 mm-gap Ni foam. With the graphene transistor fabrication process, a pre-deposited Au film as the protective layer was used during the graphene transfer. Graphene transistors showed good current saturation with drain differential conductance as low as 0.04 S mm-1 in the strong saturation region. For the devices with gate length of 2 µm, the intrinsic cut-off frequency f T and maximum oscillation frequency f max were 8.4 and 16.3 GHz, respectively, with f max/f T = 1.9 and power gain of up to 6.4 dB at 1 GHz. The electron velocity saturation induced by the surface optical phonons of SiO2 substrates was analyzed. Electron velocity saturation and ultra-thin Al2O3 gate dielectrics were thought to be the reasons for the good current saturation and high power gain of the graphene transistors.

14.
ACS Appl Mater Interfaces ; 10(21): 17630-17638, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29733187

RESUMO

Specific imaging of cancer cells has been well-accepted in cancer diagnosis although it cannot precisely mark the boundary between the normal and cancerous cells and report their mutual influence. We report a nanorod fluorescent probe of copper perylenetetracarbonate (PTC-Cu) that can specifically light up normal cells. In combination with cancer cell imaging, the cocultured normal and cancer cells can be lit up with different colors, offering a clear contrast between the normal and cancer cells when they coexist. Because cancerous cells are only 20-30% in cancer area, this provides a possibility to visibly detect the mutual influence between the cancer and normal cells during therapy. We expect this method is beneficial to better cancer diagnosis and therapy.


Assuntos
Nanotubos , Cobre , Corantes Fluorescentes , Humanos , Neoplasias
15.
Chem Commun (Camb) ; 54(47): 5960-5963, 2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29736502

RESUMO

Carbon dots (CDs) with an absolute fluorescence quantum yield of 87% are facilely prepared via irradiation of self-assembled terthiophene amphiphile TTC4L in aqueous solution by mild visible light. Visible light irradiation of TTC4L triggers the production of superoxide radicals in water, which oxidize the closely packed terthiophene group into carbon dots. Our results reveal that the molecular self-assembly may act as important precursor for the generation of single molecule-like carbon dots; this method paves the way for the fabrication of CDs of high quality.

16.
Zhongguo Zhong Yao Za Zhi ; 32(18): 1928-31, 2007 Sep.
Artigo em Zh | MEDLINE | ID: mdl-18051910

RESUMO

OBJECTIVE: To evaluate the clinical efficacy and security of super crush-run tong xinluo capsule (SCTXLC) for apoplexy due to energy-deficiency and blood-stasis. METHOD: The randomised controlled double blind non-inferiority trial versus paroxetine, parallel contrast, different Kinds of Techniques and dosage, the clinical trial design was adopted, 144 patients with stroke of convalescent stage were selected by 2 group, which course of diseases was in 2 weekens to 3 months, neurological deficit scores was 8 to 30, grade of acaties of daily living scores was 2 to 5. the treatment group (n = 72) received SCTXLC 0.26 g (a capsule), 4 capsules at a time, three times a day, while that of the control group (n = 72) received common crush-run tong xinluo capsule (CCTXLC) 0.38 g (a capsule), 4 capsules at a time, three times a day, the therapeutic course for both groups was 28 d. RESULT: The synthesis total effective rates of the stroke in treatment group and control group were 91.3% and 87.3% respectively, showing no significant difference. The Lower Bound Upper Bound of Asymptotic 95% Confidence Interval of the total effective rates difference is -4.57%, over the beforehand Lower Bound of 15%, non-inferiority trial versus paroxetine was eligible. The adverse reactions occurred was 1 patient in the treatment group and 2 patients in control group in clinical trial. CONCLUSION: SCTXLC has definite effect for apoplexy due to energy-deficiency and blood-stasis, the efficacy in the treated group was equal to that in the control group, and favourable satety for usage.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Materia Medica/química , Plantas Medicinais/química , Acidente Vascular Cerebral/tratamento farmacológico , Atividades Cotidianas , Adulto , Idoso , Animais , Cápsulas , Método Duplo-Cego , Esquema de Medicação , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pós , Acidente Vascular Cerebral/fisiopatologia , Resultado do Tratamento
17.
ACS Appl Mater Interfaces ; 8(25): 16147-53, 2016 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-27310183

RESUMO

In this report, a facile and general strategy was developed to synthesize original bamboo-shaped Te nanotubes (NTs) with well-controlled size and morphology. On the basis of the as-prepared Te NTs, porous Pt nanotubes (NTs) with excellent property and structural stability have been designed and manufactured. Importantly, we avoided the use of surface stabilizing agents, which may affect the catalytic properties during the templated synthesis process. Furthermore, Pt NTs with different morphology were successfully prepared by tuning the experimental parameters. As a result, transmission electron microscopy (TEM) study shows that both Te NTs and Pt NTs have uniform size and morphology. Following cyclic voltammogram (CV) testing, the as-prepared porous Pt NTs and macroporous Pt NTs exhibited excellent catalytic activities toward electrochemical methanol oxidation reactions due to their tubiform structure with nanoporous framework. Thus, the as-prepared Pt NTs with specific porous structure hold potential usage as alternative anode catalysts for direct methanol fuel cells (DMFCs).

18.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 25(9): 783-6, 2005 Sep.
Artigo em Zh | MEDLINE | ID: mdl-16248237

RESUMO

OBJECTIVE: To observe the clinical efficacy of shensong yangxin capsule (SYC) on ventricular premature beat (VPB) differentiated in TCM as palpitation of Qi-yin deficiency syndrome or Xin collateral stagnation syndrome, and cardiovascular autonomic nervous function in patients with coronary heart disease (CHD). METHODS: The randomized, double-blind, parallel contrast method was adopted, patients were randomly assigned by 3:1 ratio into two groups. One hundred and sixty-five patients in SYC treated group and 56 in the control group (treated with Xinlvning tablet), and the therapeutic course for both groups was 4 weeks. RESULTS: The clinical efficacy on VPB and in improving TCM syndromes was better in SYC group than that in the control group (P < 0.01). After treatment, the heart rate variability (HRV) and QT dispersion in the two groups were improved in a certain degree. The changes of SDNN, SDANN, SDNN Index and PNN50 in the two groups were significantly different (P < 0.05, P < 0.01), the efficacy in the treated group was superior to that in the control group. CONCLUSION: SYC has definite effect on VPB and TCM Syndromes, it can obviously meliorate the activity of cardiovascular autonomic nervous system in the patients with CHD.


Assuntos
Sistema Nervoso Autônomo/efeitos dos fármacos , Doença das Coronárias/complicações , Medicamentos de Ervas Chinesas/uso terapêutico , Coração/inervação , Fitoterapia , Complexos Ventriculares Prematuros/tratamento farmacológico , Adulto , Idoso , Sistema Nervoso Autônomo/fisiopatologia , Cápsulas , Doença das Coronárias/tratamento farmacológico , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complexos Ventriculares Prematuros/etiologia
19.
ACS Appl Mater Interfaces ; 6(17): 14919-22, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-25133761

RESUMO

Here we develop a synthetic protocol for assembling DNA with participating metal ions into multiple shapes. DNA molecules first form coordination complexes with metal ions and these coordination complexes become nucleation sites for primary crystals of metal inorganic salt, and then elementary units of space-filling architectures based on specific geometry form, and finally elementary units assemble into variously larger multiple architectures according to different spatial configurations. We anticipate that our strategy for self-assembling various custom architectures is applicable to most biomolecules possessing donor atoms that can form coordination complexes with metal ions. These multiple architectures provide a general platform for the engineering and assembly of advanced materials possessing features on the micrometer scale and having novel activity.


Assuntos
DNA/química , Metais/química , Animais , Bovinos , DNA/ultraestrutura , Glutationa/química , Íons , Soroalbumina Bovina/química , Espectrofotometria Ultravioleta
20.
IEEE Trans Cybern ; 43(3): 982-94, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23193245

RESUMO

Clustering validation has long been recognized as one of the vital issues essential to the success of clustering applications. In general, clustering validation can be categorized into two classes, external clustering validation and internal clustering validation. In this paper, we focus on internal clustering validation and present a study of 11 widely used internal clustering validation measures for crisp clustering. The results of this study indicate that these existing measures have certain limitations in different application scenarios. As an alternative choice, we propose a new internal clustering validation measure, named clustering validation index based on nearest neighbors (CVNN), which is based on the notion of nearest neighbors. This measure can dynamically select multiple objects as representatives for different clusters in different situations. Experimental results show that CVNN outperforms the existing measures on both synthetic data and real-world data in different application scenarios.


Assuntos
Algoritmos , Inteligência Artificial , Análise por Conglomerados , Interpretação Estatística de Dados , Modelos Estatísticos , Reconhecimento Automatizado de Padrão/métodos , Simulação por Computador
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