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1.
Nature ; 611(7937): 818-826, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36385524

RESUMO

Immune-related adverse events, particularly severe toxicities such as myocarditis, are major challenges to the utility of immune checkpoint inhibitors (ICIs) in anticancer therapy1. The pathogenesis of ICI-associated myocarditis (ICI-MC) is poorly understood. Pdcd1-/-Ctla4+/- mice recapitulate clinicopathological features of ICI-MC, including myocardial T cell infiltration2. Here, using single-cell RNA and T cell receptor (TCR) sequencing of cardiac immune infiltrates from Pdcd1-/-Ctla4+/- mice, we identify clonal effector CD8+ T cells as the dominant cell population. Treatment with anti-CD8-depleting, but not anti-CD4-depleting, antibodies improved the survival of Pdcd1-/-Ctla4+/- mice. Adoptive transfer of immune cells from mice with myocarditis induced fatal myocarditis in recipients, which required CD8+ T cells. The cardiac-specific protein α-myosin, which is absent from the thymus3,4, was identified as the cognate antigen source for three major histocompatibility complex class I-restricted TCRs derived from mice with fulminant myocarditis. Peripheral blood T cells from three patients with ICI-MC were expanded by α-myosin peptides. Moreover, these α-myosin-expanded T cells shared TCR clonotypes with diseased heart and skeletal muscle, which indicates that α-myosin may be a clinically important autoantigen in ICI-MC. These studies underscore the crucial role for cytotoxic CD8+ T cells, identify a candidate autoantigen in ICI-MC and yield new insights into the pathogenesis of ICI toxicity.


Assuntos
Linfócitos T CD8-Positivos , Imunoterapia , Miocardite , Miosinas Ventriculares , Animais , Camundongos , Autoantígenos/imunologia , Linfócitos T CD8-Positivos/imunologia , Antígeno CTLA-4/deficiência , Antígeno CTLA-4/genética , Imunoterapia/efeitos adversos , Miocardite/induzido quimicamente , Miocardite/etiologia , Miocardite/mortalidade , Miocardite/patologia , Miosinas Ventriculares/imunologia
2.
J Biochem Mol Toxicol ; 37(4): e23297, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36639866

RESUMO

Colorectal cancer (CRC) is the fourth most deadly cancer worldwide, drug resistance impedes treatment of CRC. It is still urgent to find new molecular targets to improve the sensitivity of chemotherapeutic drugs. In this study, circ-ERBB2 was upregulated in CRC cells. Upregulation of circ-ERBB2 promoted CRC cells proliferation and clone formation, but inhibited apoptosis. We identified miR-181a-5p as circ-ERBB2's target. The effect of miR-181a-5p on CRC cells was contrary to circ-ERBB2, miR-181a-5p downregulation abolished the function of circ-ERBB2 silencing in CRC cells. In addition, phosphatase and tensin homolog (PTEN) was verified as miR-181a-5p's downstream target, circ-ERBB2 activates the Akt pathway and inhibits cell apoptosis through modulating miR-181a-5p/PTEN. Circ-ERBB2 silencing significantly reduced CRC cell resistance to 5-FU. miR-181a-5p downregulation abolished the role of circ-ERBB2 knockdown in CRC cell resistance to 5-FU. In conclusion, upregulation of circ-ERBB2 promoted the malignancy of CRC and reduced CRC cell resistance to 5-FU. Besides, additional mechanism study provided a novel regulatory pathways that circ-ERBB2 knockdown promoted CRC cell sensitivity to 5-FU by regulating miR-181a-5p/PTEN/Akt pathway. This research indicated that circ-ERBB2 may be a valuable biomarker for the diagnosis and treatment of CRC.


Assuntos
Neoplasias Colorretais , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Fluoruracila/farmacologia , Proliferação de Células , PTEN Fosfo-Hidrolase/genética , Receptor ErbB-2/genética
3.
Environ Toxicol ; 38(11): 2705-2716, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37471645

RESUMO

Curcumin shows an anti-cancer role in many kinds of tumors. However, the mechanism of its anti-tumor function in esophageal squamous cell carcinoma (ESCC) remains largely unknown. Herein, we explored the therapeutic potential of curcumin for esophageal cancer. Curcumin could time- and dose-dependently inhibit ESCC cells activity. Additionally, ESCC cells exposed to 20 µM of curcumin exhibited significantly decreased proliferative and invasive capacities, as well as enhanced cell apoptosis. ESCC tissues and cells exhibited significantly increased circNRIP1 expression when compared to their counterparts. circNRIP1 knockdown markedly impaired cell proliferation, clone formation, cell migration and invasion but promoted apoptosis. Exposure to 10-20 µM of curcumin inhibited circNRIP1 expression, however, overexpression of circNRIP1 could significantly restored the biological characteristics that were inhibited by curcumin exposure in vivo and in vitro. circNRIP1 promoted the malignancy of ESCC by combining miR-532-3p, and downstream AKT3. Curcumin inhibited AKT phosphorylation by up-regulating miR-532-3p expression, thereby inhibiting the activation of the AKT pathway. In summary, curcumin is a potent inhibitor of ESCC growth, which can be achieved through the regulation of the circNRIP1/miR-532-3p/AKT pathway. This research may provide new mechanisms for curcumin to inhibit the malignant development of ESCC.


Assuntos
Curcumina , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , MicroRNAs , Humanos , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Neoplasias Esofágicas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Curcumina/farmacologia , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Movimento Celular , Regulação Neoplásica da Expressão Gênica
4.
Mikrochim Acta ; 190(7): 263, 2023 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-37332000

RESUMO

An up-conversion molecularly imprinted ratiometric fluorescent probe with a monodisperse nuclear-satellite structure and its test strip are designed which can avoid fluorescent background interference to detect Sudan I in chili powder highly selective and sensitive. The detection mechanism is based on the selective recognition of Sudan I by imprinted cavities on the surface of ratiometric fluorescent probe and the inner filter effect between Sudan I molecules and the emission of up-conversion materials (NaYF4:Yb,Tm). Under optimized experimental conditions, the response of fluorescent ratio signals (F475/F645) of this test strip show a good linear relationship in the range 0.02-50 µM Sudan I. The limits of detection and quantitation are as low as 6 nM and 20 nM, respectively. Sudan I is selectively detected in the presence of fivefold higher concentrations of interfering substances (imprinting factor up to 4.4). Detection of Sudan I in chili powder samples show ultra-low LOD (44.7 ng/g), satisfactory recoveries (94.99-105.5%) and low relative standard deviation (≤ 2.0%). This research offers a reliable strategy and promising scheme for highly selective and sensitive detection of illegal additives in complex food matrix via an up-conversion molecularly imprinted ratiometric fluorescent test strip.


Assuntos
Impressão Molecular , Corantes Fluorescentes , Pós , Limite de Detecção
5.
Arch Virol ; 167(5): 1369-1373, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35391577

RESUMO

Mycoviruses are widespread in all major groups of plant-pathogenic fungi. So far, only one mycovirus has been reported to be associated with Fusarium pseudograminearum, the causal agent of Fusarium crown rot of wheat. In this study, a double-stranded RNA (dsRNA) segment was isolated from F. pseudograminearum strain JW2-1, and the sequence of its full-length cDNA (3077 nucleotides) was determined. Sequence analysis using the fungal mitochondrial genetic code (UGA coding for tryptophan) indicated that a single large open reading frame (ORF) is present on the positive strand of this dsRNA segment. The ORF encodes a putative RNA-dependent RNA polymerase (RdRp) of 748 amino acids (aa) with a molecular mass of 83.46 kDa. BLASTp analysis revealed that its aa sequence was 28.49-44.03% identical to those of viruses of the family Mitoviridae, with the most similarity to the corresponding RdRp sequences of Ophiostoma mitovirus 1c (44.03% identity) and Ophiostoma mitovirus 1b (40.33% identity). Phylogenetic analysis showed that this mycovirus, designated as "Fusarium pseudograminearum mitovirus 1" (FpgMV1), should be classified as a member of a new species in the earlier proposed genus "Duamitovirus" within the family Mitoviridae. To our best of our knowledge, this is the first report of a mitovirus infecting F. pseudograminearum.


Assuntos
Micovírus , Fusarium , Vírus de RNA , Genoma Viral , Fases de Leitura Aberta , Filogenia , Doenças das Plantas/microbiologia , RNA de Cadeia Dupla/genética , RNA Viral/genética , RNA Polimerase Dependente de RNA/genética
6.
J Biochem Mol Toxicol ; 36(2): e22959, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34766670

RESUMO

Long noncoding RNAs (LncRNAs) have been reported to play a vital role in the development of oesophageal squamous cell carcinoma (OSCC). Our previous study revealed that the significant upregulation of the LncRNA small nucleolar RNA host gene 6 (SNHG6) in OSCC promotes OSCC tumourigenesis. However, the mechanisms underlying the dynamics of SNHG6 expression in OSCC have rarely been studied. In this study, we verified the tumour-promoting effect of SNHG6 through sponging miR-101-3p, and their levels were negatively correlated in human samples of OSCC. In addition, miR-101-3p overexpression reversed the effect of SNHG6. Moreover, we confirmed that SNHG6/miR-101-3p affects OSCC by regulating the expression of the enhancer of zeste 2 (EZH2). The effect of EZH2 silencing resembled closely that of SNHG6 knockdown. EZH2 silencing inhibited the expression of protein cyclin D1 and ß-catenin, but in contrast, it enhanced the expression of E-cadherin. These findings demonstrated the oncogenic role of SNHG6, which promotes OSCC progression by regulating the expression of EZH2 through its interaction with miR-101-3p. These findings may help in improving the diagnosis and treatment methods of OSCC.


Assuntos
Regulação para Baixo , Proteína Potenciadora do Homólogo 2 de Zeste/biossíntese , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , MicroRNAs/biossíntese , Proteínas de Neoplasias/biossíntese , RNA Longo não Codificante/metabolismo , RNA Neoplásico/metabolismo , Linhagem Celular Tumoral , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Humanos , MicroRNAs/genética , Proteínas de Neoplasias/genética , RNA Longo não Codificante/genética , RNA Neoplásico/genética
7.
Plant Dis ; 2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35285257

RESUMO

Maize (Zea mays L.) is one of the most important food and feed crops in China, with a cultivation area of more than 40 million hectares (http://www.fao.org/faostat/en/#data/QC). In July 2021, a serious maize seeding blight occurred in Changjia Town, Gaoqing Country, Zibo City, Shandong Province, China, and the disease incidence was up to 50% in some fields. The root system of infected plants displayed poor development. The primary roots were brown and rotted. The leaves at the base of the plants were drying up, then the whole plant withered. To determine the cause agent of the disease, symptomatic roots of diseased seedlings were collected and surface-sterilized (70% ethanol for 30 s and 3% sodium hypochlorite (NaClO) for 90 s), subsequently rinsed three times with sterile distilled water, placed on potato dextrose agar (PDA), then incubated at 25°C for 2 days. Two cultures with similar morphological characteristics were purified through single-spore isolation technique and identified by morphology and molecular methods as Fusarium pseudograminearum O'Donnell & T. Aoki 1999. Plentiful macroconidia formed in 5-day-old carboxymethyl cellulose (CMC) cultures; microconidia were absent. Macroconidia were thick-walled and curved, usually 3- to 5- septa, 31.6 ± 0.6 µm × 4.8 ± 0.1 µm (n = 50). Colony pigmentation on PDA was pink to red, with white to pink aerial mycelia on PDA cultures was abundant and filled the petri dishes. For molecular identification, the rDNA internal transcribed spacer (ITS) gene and translation elongation factor 1 alpha (TEF-1α) gene of two isolates (SAIA41B and SAIA41C) were amplified with ITS1/ITS4 (White et al., 1990) and EF-1/EF-2 (O'Donnell et al., 1998), respectively. Blastn analysis of both the ITS sequence (accession numbers OM108101 and OM108102) and TEF-1α sequence (accession numbers OM142205 and OM142206) revealed 100% (481/481 bp for ITS and 637/637 bp for TEF-1α) sequence identity with the sequences of F. pseudograminearum reported in GenBank (MW699613 for ITS and JN862232 for TEF-1α). The molecular identification was further confirmed by the F. pseudograminearum species-specific PCR primers Fp1-1/Fp1-2 (Aoki and O'Donnell 1999). The expected 523-bp fragments were obtained for isolates SAIA41B and SAIA41C. In the pathogenicity test, healthy germinating maize roots (Zhengdan958) were inoculated with PDA culture blocks of isolate SAIA41C. Plants inoculated only with PDA culture blocks served as controls. Maize plants were put in petri dishes and placed in an incubator with a 12-h photoperiod at 25 oC and 100% relative humidity. Seven days later, roots of the plants inoculated with isolate SAIA41C were poorly developed and became brown necrotic and rotted, which were identical to the symptoms observed in the fields, whereas the roots of control plants were developed normally. The pathogen was re-isolated from the necrotic tissue of the inoculated roots but not from the control plants, and its identity was confirmed by PCR with the primes Fp1-1/Fp1-2 described above, fulfilling Koch's Postulates. To our knowledge, this is the first report of maize seedling blight caused by F. pseudograminearum in China. Our finding indicates the potential spread of F. pseudograminearum on maize, and more attention should be paid to prevention and control of maize seedling blight caused by F. pseudograminearum. The author(s) declare no conflict of interest. Acknowledgements: This research was supported by National Natural Science Foundation of China (No. 32102181), Shandong Provincial Natural Science Foundation (No. ZR2021QC059), Wheat Industry Technology System of Shandong Province (No. SDAIT-01-10), and Agricultural Science and Technology Innovation Project of SAAS (No. CXGC2021A38 and CXGC2021A33).

8.
Opt Express ; 29(15): 24255-24263, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34614674

RESUMO

Graphene, combined with plasmonic nanostructures, shows great promise for achieving desirable photodetection properties and functionalities. Here, we theoretically proposed and experimentally demonstrated a graphene photodetector based on the metamaterial absorber in the visible and near-infrared wavebands. The experimental results show that the metamaterial-based graphene photodetector (MGPD) has achieved up to 3751% of photocurrent enhancement relative to an antennasless graphene device at zero external bias. Furthermore, the polarization-independent of photoresponse has resulted from the polarization-insensitive absorption of symmetric square-ring antennas. Moreover, the spectral-dependent photocurrent enhancement, originated from the enhanced light-trapping effect, was experimentally confirmed and understood by the simulated electric field profiles. The design contributes to the development of high-performance graphene photodetectors and optoelectronic devices.

9.
Langmuir ; 37(8): 2619-2628, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33586432

RESUMO

Hollow mesoporous silica nanoparticles (HMSNs) served as nanocarriers for transporting doxorubicin hydrochloride (DOX) and indocyanine green (ICG) and were incorporated into a pH-sensitive targeted drug delivery system (DDS). Boronate ester bonds were employed to link HMSNs and dopamine-modified hyaluronic acid (DA-HA), which acted as both the "gatekeeper" and targeting agents (HMSNs-B-HA). Well-dispersed HMSNs-B-HA with a diameter of about 170 nm was successfully constructed. The conclusion was drawn from the in vitro drug release experiment that ICG and DOX (ID) co-loaded nanoparticles (ID@HMSNs-B-HA) with high drug loading efficiency could sustain drug release under acidic conditions. More importantly, in vitro cell experiments perfectly showed that ID@HMSNs-B-HA could well inhibit murine mammary carcinoma (4T1) cells via chemotherapy combined with photodynamic therapy and accurately target 4 T1 cells. In summary, all test results sufficiently demonstrated that the prepared ID@HMSNs-B-HA was a promising nano-DDS for cancer photodynamic combined with chemotherapy.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Animais , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Ácido Hialurônico , Concentração de Íons de Hidrogênio , Camundongos , Neoplasias/tratamento farmacológico , Porosidade , Dióxido de Silício
10.
Plant Dis ; 2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-33983797

RESUMO

Head lettuce (Lactuca sativa L.) is an important crop for fresh consumption in China. In Shandong Province, head lettuce is planted in spring and in autumn each year. Because of the on-and-off rain for three weeks, head lettuce plants planted directly into the field in Jiyang City, in July 2017, 20% of the plants rapidly showed symptoms of rotting, water-soaked lesions on roots and stem bases, and then death. The diseased plants first appeared in low-lying areas prone to water accumulation. One-millimeter pieces were excised from water-soaked roots and stem bases, dipped in a 0.2% calcium hypochlorite solution for 10 min, then placed on V8 medium, and incubated in the dark at 28°C for 5 d. Two Pythium-like strains were isolated from the roots and stems. The isolates transferred to CMA and grown for 7 d, and the morphological characteristics of the two isolates on corn meal agar (CMA) were white with dense, cottony, aerial and well-branched mycelia. The two isolates produced sporangia, oogonia, antheridia and oospores. Most of the sporangia were lobate. The oogonia were smooth, nearly globose and terminal. Oospores were globose, smooth and aplerotic. The average dimensions of 50 oogonia and oospores respectively ranged from 19.5 to 25.2 (av. 23.1) µm and 17.8 to 22.3 (av. 19.9) µm. The antheridia were broadly sac-shaped. The isolates morphological characteristics were consistent with P. aphanidermatum (van der Plaats-Niterink, 1981). The COI gene and ITS region of the rDNA were amplified and sequenced using primers FM55/FM52R (Long et al. 2012) and ITS1/ITS4 (White et al. 1990), respectively. The two aligned COI sequences were identical for both isolates, as were the two ITS sequences. BLASTn analysis of the 1,133-bp COI sequence (accession no. MT952703) resulted in a 100% identity with accession number AY129164 from Lactuca sativa, which belongs to P. aphanidermatum, and the 808-bp ITS sequence (accession no. MT921597) showed a 99% identity with Genbank accession number HQ643442 belonging to P. aphanidermatum. Koch's postulates were conducted by first soaking corn kernels for 24 h in water, and then autoclaving for 2 h at 121˚C. Isolate SDHL-1 was grown on CMA for 10 days, after which agar plugs were transferred to the sterilized corn kernels and incubated at 28℃ for approximately 15 d, until the corn kernels were covered in white hyphae. Ten healthy head lettuce plants were transplanted into a sterilized loam potting soil artificially infested with the corn inoculum (3 g inoculum per 100 g loam mixture). Inoculated plants and noninoculated controls were maintained in a greenhouse at 28°C and 100% relative humidity with a 12-h photoperiod; the experiment was repeated once. All twenty inoculated plants exhibited symptoms within one week similar to those observed. Pythium aphanidermatum was recovered only from the water-soaked roots and stem bases of inoculated plants and the re-isolated cultures again identified based on morphological characteristics and sequencing of the ITS and COI genes. No symptoms were observed on the control plants. Sclerotinia sclerotiorum is reported to cause stem base rot of L. sativa in China (Zhou et al. 2011). To our knowledge, however, this is the first report of root rot of head lettuce caused by Pythium aphanidermatum. Identification of the pathogen will assist in devising strategies to reduce yield loss.

11.
Plant Dis ; 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32820675

RESUMO

American ginseng (Panax quinquefolius) is a perennial herb whose dried roots are used for health care products, medicine, and food in China (Yuan et al. 2010). Shandong Province is the main area growing American ginseng and contributes more than 50% of the production in China. Wendeng city, located in the east of Shandong Peninsula, is the primary production area of American ginseng in Shandong Province since it has four distinct seasons, sufficient light, loose soil (pH 5.5~7.0), and with thus a similar geographical environment and climate conditions to the American ginseng production area of the United States and Canada. In March 2016, 2-year old American ginseng plants that were planted directly into the ground in the greenhouses in Wendeng city, contained up to 6-10% stunted plants. Water-soaked lesions were observed on the crowns and the tips of fine roots. The leaves of the infected plants became scalded, dark green starting at the top of the plants and gradually move downward. Moreover, the leaves and petioles gradually curled withered and drooped, and the whole plant collapsed. Tissue samples, 10 mm in size, were excised from the water-soaked roots and crowns of diseased plants, rinsed under running water for 24 hours, dipped in a 0.2% calcium hypochlorite solution for 10 minutes, placed on sterile filter paper to dry and then placed on V8 medium (200 mL V8 Campbell Soup, 15 g agar, 0.2 g CaCO3, and 1 L distilled water) and incubated in the dark at 28 °C for 5 days. Five Pythium-like isolates which were arachnoid-cottony on cornmeal agar were isolated and they all produced hyphal swellings, oogonia, antheridia and oospores. Oospores were globose, smooth and plerotic, with some being aplerotic. The dimensions of hyphal swellings, oogonia and oospores respectively ranged from 9.0 to 21.3 (average 14.1) µm, 12.9 to 22.5 (average 18.2) µm, and 12.5 to 20.5 (average 16.7) µm. Finger-like projections were uniformly distributed on the walls of the oogonia and the antheridia were curved rods. The five Pythium-like isolates were identified as P. spinosum based on morphological characteristics (van der Plaats-Niterink, 1981). Genomic DNA was extracted from the isolates of the Pythium sp. using a DNA extraction kit (OMEGA, U.S.A.). The cytochrome c oxidase subunit I (COI) gene and internal transcribed spacer (ITS) region rDNA were amplified and sequenced using primers FM55/FM52R (Long et al. 2012) and ITS1/ITS4, respectively (White et al.1990). The five COI sequences were aligned and were identical for all five isolates, as well as the five ITS sequences. BLASTn analysis of the 538-bp COI sequence (accession no. MT822775) resulted in a 99% identity with that of the P. spinosum strain CBS122663 (accession no. HQ708832.1), and the 916-bp ITS sequence (accession no. MN847595) showed 100% identity with Genbank accession number AB217665 belonging to P. spinosum. Koch's postulates were confirmed. Corn kernels that had been soaked in water for 24 hours in water, autoclaved for 2 hours at 121˚C and allowed to cool were inoculated with agar plugs of P. spinosum grown on corn meal agar medium (CMA) for 10 days. The inoculated corn kernels were incubated at 28 ℃ for 13~15 days, until the corn kernels were covered with white hypha of P. spinosum. Ten healthy approximately 2-years old American ginseng plants growing in Wengdeng greenhouses were transplanted into a sterilized potting soil that was artificially infested with the corn inoculum (3 g inoculum per 100 g loam mixture). Inoculated and non-inoculated control plants were maintained in a greenhouse with a roof covered with sunshade net at 28 °C and 100% relative humidity. The experiment was repeated once. Four days after inoculation (DAI), the crown of inoculated plants developed water-soaked symptoms similar to those observed in field. No symptoms developed on the control plants. By 7 DAI, the inoculated fine roots and crowns showed water-soaked lesions identical to those observed in field, whereas control plants remained symptomless. The re-isolated isolate of P. spinosum was identical morphologically and by DNA sequence analysis to the original isolate. To our knowledge, this is the first report of root rot on American ginseng caused by P. spinosum in China and worldwide. Identification of the pathogen will assist in devising strategies to protect this important medicine plant from the pathogen, and to prevent yield losses.

12.
Zhongguo Zhong Yao Za Zhi ; 45(7): 1670-1675, 2020 Apr.
Artigo em Zh | MEDLINE | ID: mdl-32489048

RESUMO

Developing high-quality standard is useful for promoting the quality of traditional Chinese medicine injections, which could be evaluated by establishing the comprehensive quality control method. A method for simultaneous determination of salvianolic acid B, rosmarinic acid and lithospermic acid in Salvianolate for Injection was developed for quantitative analysis of multi-components with single-marker(QAMS). ZORBAX Eclipse Plus C_(18) chromatographic column was adopted, with 0.1% phosphoric acid and acetonitrile as mobile phase. The flow rate was set at 1 mL·min~(-1). The column temperature was set at 20 ℃, and the detection wavelength was 286 nm. Salvianolic acid B was used as internal reference. The relative correction factors of rosmarinic acid and lithospermic acid(f_(s/i)) were 0.58 and 0.94, respectively. About 85% of substances in Salvianolate for Injection were quantified by the established QAMS method. The analysis of different batches of intermediates and preparations during four years showed that the contents of salvianolic acid B were 77.1%-81.5% in intermediates and 70.5%-80.1% in preparations; The total content of rosmarinic acid and lithospermic acid was about 6%. The ratio of rosmarinic acid to lithospermic acid was(3.4∶1-10∶1) and(2.5∶1-5∶1), respectively, which showed that the ratio was more stable in preparation. The QAMS method established is feasible for comprehensive quality control of multiple components of in Salvianolate for Injection.


Assuntos
Medicamentos de Ervas Chinesas , Extratos Vegetais/análise , Cromatografia Líquida de Alta Pressão , Medicina Tradicional Chinesa
13.
Inorg Chem ; 57(24): 15361-15369, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30480436

RESUMO

Luminescence efficiency of trivalent lanthanide-doped upconversion (UC) materials is significantly limited by luminescence concentration quenching. In this work, red UC emission is dramatically enhanced in Er3+-sensitized NaLuF4 UC crystals through energy trapping under multiple excitation wavelengths. Cross-relaxation quenching and the energy migration to internal lattice defects are simultaneously suppressed by confining the excitation energy in the Er3+ activator after introducing the Tm3+ or Ho3+ energy trapping center. The enhanced red UC emission (Er3+: 660 nm) mainly comes from the effective excitation energy confinement by Tm3+ and Ho3+ trapping centers through an easy energy transfer between Er3+ and Tm3+/Ho3+: 4I11/2 (Er3+) → 3H5 (Tm3+) → 4I13/2 (Er3+) and 4I11/2 (Er3+) → 5I6 (Ho3+) → 4I13/2 (Er3+). It is found that the confining efficiency of excitation energy in Er3+-sensitized NaLuF4 crystals is higher than that in Yb3+/Er3+ cosensitized NaLuF4 crystals, and the luminescence efficiency of Er3+-sensitized NaLuF4 crystals is much higher than that of Er3+-based host sensitization UC crystals (NaErF4). Moreover, Er3+-sensitized UC particles can be efficiently excited by three different wavelengths (808, 980, and 1532 nm), indicating huge advantages for applications in bioimaging, anticounterfeiting, and solar cells.

14.
Small ; 13(14)2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28092436

RESUMO

Detecting and analyzing pathogenic bacteria in an effective and reliable manner is crucial for the diagnosis of acute bacterial infection and initial antibiotic therapy. However, the precise labeling and analysis of bacteria at the single-bacterium level are a technical challenge but very important to reveal important details about the heterogeneity of cells and responds to environment. This study demonstrates an optical strategy for single-bacterium labeling and analysis by the cotrapping of single upconversion nanoparticles (UCNPs) and bacteria together. A single UCNP with an average size of ≈120 nm is first optically trapped. Both ends of a single bacterium are then trapped and labeled with single UCNPs emitting green light. The labeled bacterium can be flexibly moved to designated locations for further analysis. Signals from bacteria of different sizes are detected in real time for single-bacterium analysis. This cotrapping method provides a new approach for single-pathogenic-bacterium labeling, detection, and real-time analysis at the single-particle and single-bacterium level.


Assuntos
Bactérias , Nanopartículas/química
15.
Phys Chem Chem Phys ; 19(24): 15693-15700, 2017 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28540953

RESUMO

We propose a novel and efficient F- anion doping strategy for enhancing upconversion luminescence in upconversion nanophosphors. NaGd(MoO4)2:Yb3+/Er3+ nanophosphors doped with different F- contents are synthesized hydrothermally. Rietveld refinement results obtained from X-ray diffraction data indicate that the Gd-O bond length decreases and the O-Gd-O bond angle varies with increasing F- content, resulting in augmented local crystal field strength and distorted local site symmetry of the dopant lanthanide sites. Judd-Ofelt analysis suggests that the calculated radiative quantum efficiency of the 4S3/2 level and the radiative branching ratio of 4S3/2 → 4I15/2 transition in F--doped NaGd(MoO4)2:Yb3+/Er3+ nanophosphors are much greater than those in F- anion-free samples. It is inferred that F- anion doping helps to reduce the nonradiative transition probabilities based on the luminescence dynamics. Rietveld refinement results and Judd-Ofelt analysis confirm jointly that doping of interstitial F- anions could enhance local crystal field strength with odd parity and modify site symmetry of the lanthanide activator ions, leading to enhanced radiative transitions and inhibited nonradiative transitions. A maximum of 17-fold enhancement of total emission intensity is found in NaGd(MoO4)2:Yb3+/Er3+/F- nanophosphors compared with F- anion-free counterparts. The proposed F- anion doping strategy provides an alternative approach for enhancing upconversion luminescence efficiency and could be extended to other inorganic upconversion nanomaterials.

16.
Acta Pharmacol Sin ; 38(3): 415-423, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28112181

RESUMO

The highly variable pharmacokinetics and narrow therapeutic window of tacrolimus (TAC) has hampered its clinical use. Genetic polymorphisms may contribute to the variable response, but the evidence is not compelling, and the explanation is unclear. In this study we attempted to find previously unknown genetic factors that may influence the TAC dose requirements. The association of 105 pathway-related single nucleotide polymorphisms (SNPs) with TAC dose-adjusted concentrations (C0/D) was examined at 7, 30 and 90 d post-operation in 382 Chinese kidney transplant recipients. In CYP3A5 non-expressers, the patients carrying the IL-3 rs181781 AA genotype showed a significantly higher TAC logC0/D than those with the AG genotype at 30 and 90 d post-operation (AA vs AG, 2.21±0.06 vs 2.01±0.03, P=0.004; and 2.17±0.06 vs 2.03±0.03, P=0.033, respectively), and than those with the GG genotype at 30 d (AA vs GG, 2.21±0.06 vs 2.04±0.03, P =0.011). At 30 d, the TAC logC0/D in the grouped AG+GG genotypes of CTLA4 rs4553808 was significantly lower than that in the AA genotype (P =0.041) in CYP3A5 expressers, but it was higher (P=0.008) in the non-expressers. We further validated the influence of CYP3A5 rs776746, CYP3A4 rs2242480 and rs4646437 on the TAC C0/D; other candidate SNPs were not associated with the differences in TAC C0/D. In conclusion, genetic polymorphisms in the immune genes IL-3 rs181781 and CTLA4 rs4553808 may influence the TAC C0/D. They may, together with CYP3A5 rs776746, CYP3A4 rs2242480 and rs4646437, contribute to the variation in TAC dose requirements. When conducting individualized therapy with tacrolimus, these genetic factors should be taken into account.


Assuntos
Antígeno CTLA-4/genética , Imunossupressores/administração & dosagem , Interleucina-3/genética , Tacrolimo/administração & dosagem , Adulto , Povo Asiático , Feminino , Rejeição de Enxerto/genética , Humanos , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Farmacogenética , Polimorfismo de Nucleotídeo Único
17.
Breed Sci ; 67(3): 296-306, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28744183

RESUMO

Rapeseed (Brassica napus L.) is one of the most important oil crops almost all over the world. Seed-related traits, including oil content (OC), silique length (SL), seeds per silique (SS), and seed weight (SW), are primary targets for oil yield improvement. To dissect the genetic basis of these traits, 192 recombinant inbred lines (RILs) were derived from two parents with distinct oil content and silique length. High-density linkage map with a total length of 1610.4 cM were constructed using 1,329 double-digestion restriction site associated DNA (ddRAD) markers, 107 insertion/deletions (INDELs), and 90 well-distributed simple sequence repeats (SSRs) markers. A total of 37 consensus quantitative trait loci (QTLs) were detected for the four traits, with individual QTL explained 3.1-12.8% of the phenotypic variations. Interestingly, one OC consensus QTL (cqOCA10b) on chromosome A10 was consistently detected in all three environments, and explained 9.8% to 12.8% of the OC variation. The locus was further delimited into an approximately 614 kb genomic region, in which the flanking markers could be further evaluated for marker-assisted selection in rapeseed OC improvement and the candidate genes targeted for map-based cloning and genetic manipulation.

18.
Echocardiography ; 33(5): 724-33, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26857344

RESUMO

BACKGROUND: The purpose of this meta-analysis was to analyze the clinical relevance of left atrial (LA) strain to predict recurrence of atrial fibrillation (AF) after catheter ablation (CA). METHODS AND RESULTS: We searched in different databases (Medline, EMBASE, and Cochrane) prospective studies that analyzed LA strain before CA. Eight studies (2 with only paroxysmal AF and 6 with mixed population of paroxysmal and persistent AF) were included in the final analysis (total patient number = 686). Patients with recurrence of AF were principally characterized by lower LA strain in comparison with those without AF recurrence (mean 18.4% [range 8.8-24.5%] versus 25.3% [13.6-32.7%], weighted mean difference -4.89% [95% CI -5.83% to -3.95%], P < 0.001). In addition, receiver operating curves shown that LA strain was strongly associated with recurrence of AF after CA (weighted mean: AUC 0.798 [95% CI 0.700-0.943], cutoff 22.8% [18.8-30%], sensitivity 78% [65-86%], and specificity 75% [66-100%]). In line, these results were similar using LA strain with QRS-analysis and P-analysis as well as using different software package such as Echo-Pac, QLab, TomTec, and VVI. CONCLUSION: In patients with AF candidate for CA, the analysis of the LA using LA strain could be of great usefulness to identify patients with high risk of AF recurrence. Nonetheless, further studies are needed to establish the clinical relevance of LA strain in patients with persistent AF.


Assuntos
Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Ablação por Cateter/estatística & dados numéricos , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/fisiopatologia , Fibrilação Atrial/epidemiologia , Progressão da Doença , Módulo de Elasticidade , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/métodos , Prognóstico , Recidiva , Reprodutibilidade dos Testes , Medição de Risco/métodos , Sensibilidade e Especificidade , Resultado do Tratamento
19.
Opt Express ; 23(17): 21549-64, 2015 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-26368135

RESUMO

Through gating spectrum plane of multiple planar aligned OLED microdisplays by a timely sequential manner, a super-multiview (SMV) three-dimensional (3D) display based on spatiotemporal-multiplexing was developed in our previous paper. But an upper limit of the allowable sub-viewing-zones (SVZs) for an OLED microdisplay did exist in the previous system, even if microdisplays with very high frame rates could be commercially available. In this manuscript, an improved spatiotemporal-multiplexing SMV displays system is developed, which removes the above limitation through controllable fusing of light beams from adjacent OLED microdisplays. The employment of a liquid-crystal panel as the gating-aperture array allows the improved system to accommodate multiple rows of OLED microdisplays for denser SVZs. Experimentally, a prototype system is demonstrated by 24 OLED microdisplays, resulting in 120 SVZs with an interval small to 1.07mm.

20.
Phys Chem Chem Phys ; 17(29): 19515-26, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26144530

RESUMO

A series of NaLuF4:Yb(3+),Ho(3+) nano/micro-crystals with different crystal structures were synthesized via a hydrothermal method using citric acid as a chelating agent. The influences of NaF content, Li(+) doping, reaction temperature and reaction time on the crystal structure and shape of the as-synthesized NaLuF4 crystals were systematically investigated. To the best of our knowledge, it is the first time to report Li(+) doped α-NaLuF4:Yb(3+),Ho(3+) nanocrystals and the phase transformation by introducing Li(+) in NaLuF4 crystals. As for Li(+) doped α-NaLuF4, UC luminescence intensities of green emission (538 nm) and red emission (644 nm) in α-NaLuF4:Yb(3+),Ho(3+) nanocrystals with 20 mol% Li(+) doping are enhanced by 20 and 3.5 times compared to their Li(+)-free counterpart. As for Li(+) doped α/ß-mixed NaLuF4, with the increase of Li(+) content, the phase transforms from the α/ß-mixed phase to hexagonal then to cubic. UC emissions of 538 nm and 644 nm in NaLuF4:Yb(3+),Ho(3+) crystals doped with 5 mol% Li(+) are enhanced by 26.5 and 23 times, respectively. Besides, it is found that with the higher temperature and prolonged time, the morphology of NaLuF4 changes from nanoparticles to microtubes, resulting in the dramatic increase of UC emission intensity. The effects of Li(+) doping, reaction temperature and reaction time on the enhancement of UC emission intensity are discussed in detail. This study provides an effective and facile approach to obtain nano/micro-crystals with controllable structures and excellent optical properties.


Assuntos
Flúor/química , Hólmio/química , Luminescência , Lutécio/química , Sódio/química , Itérbio/química , Lítio/química , Estrutura Molecular , Nanopartículas/química , Tamanho da Partícula , Propriedades de Superfície
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