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1.
BMC Pulm Med ; 23(1): 492, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057798

RESUMO

Small cell transformation was one mechanism by which EGFR-mutation NSCLC acquired resistance after tyrosine kinase inhibitors (TKIs) treatment. A few reports of small cell transformation occurred in other oncogene-driven lung cancers. We found the first case of transformation of a RET-rearranged lung adenocarcinoma to SCLC after selpercatinib, a novel highly selective RET TKIs. Whole-exome sequencing (WES) was used to explore alteration in gene expression in tumor tissue at initial diagnosis and after transformation into small cell carcinoma. We found that transformed into SCLC tumor tissue had inactivation of RB1 and TP53, with RET fusion was still present. In addition, the APOBEC family of cytidine deaminases appeared amplification. Although RET rearrangement still existed, using another RET TKIs was ineffective, and etoposide plus platinum might be an effective rescue treatment.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Sequenciamento do Exoma , Receptores ErbB/genética , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/patologia , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Mutação , Proteínas Proto-Oncogênicas c-ret/genética
2.
Entropy (Basel) ; 25(1)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36673296

RESUMO

Noise exists inherently in realistic quantum systems and affects the evolution of quantum systems. We investigate the dynamics of quantum networks in noisy environments by using the fidelity of the quantum evolved states and the classical percolation theory. We propose an analytical framework that allows us to characterize the stability of quantum networks in terms of quantum noises and network topologies. The calculation results of the framework determine the maximal time that quantum networks with different network topologies can maintain the ability to communicate under noise. We demonstrate the results of the framework through examples of specific graphs under amplitude damping and phase damping noises. We further consider the capacity of the quantum network in a noisy environment according to the proposed framework. The analytical framework helps us better understand the evolution time of a quantum network and provides a reference for designing large quantum networks.

3.
BMC Biol ; 19(1): 118, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34130700

RESUMO

BACKGROUND: Species domestication is generally characterized by the exploitation of high-impact mutations through processes that involve complex shifting demographics of domesticated species. These include not only inbreeding and artificial selection that may lead to the emergence of evolutionary bottlenecks, but also post-divergence gene flow and introgression. Although domestication potentially affects the occurrence of both desired and undesired mutations, the way wild relatives of domesticated species evolve and how expensive the genetic cost underlying domestication is remain poorly understood. Here, we investigated the demographic history and genetic load of chicken domestication. RESULTS: We analyzed a dataset comprising over 800 whole genomes from both indigenous chickens and wild jungle fowls. We show that despite having a higher genetic diversity than their wild counterparts (average π, 0.00326 vs. 0.00316), the red jungle fowls, the present-day domestic chickens experienced a dramatic population size decline during their early domestication. Our analyses suggest that the concomitant bottleneck induced 2.95% more deleterious mutations across chicken genomes compared with red jungle fowls, supporting the "cost of domestication" hypothesis. Particularly, we find that 62.4% of deleterious SNPs in domestic chickens are maintained in heterozygous states and masked as recessive alleles, challenging the power of modern breeding programs to effectively eliminate these genetic loads. Finally, we suggest that positive selection decreases the incidence but increases the frequency of deleterious SNPs in domestic chicken genomes. CONCLUSION: This study reveals a new landscape of demographic history and genomic changes associated with chicken domestication and provides insight into the evolutionary genomic profiles of domesticated animals managed under modern human selection.


Assuntos
Galinhas , Domesticação , Animais , Animais Domésticos/genética , Galinhas/genética , Genoma , Genômica , Humanos
4.
J Sci Food Agric ; 102(15): 6858-6867, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35654754

RESUMO

BACKGROUND: High-quality tea requires leaves of similar size and tenderness. The grade of the fresh leaves determines the quality of the tea. The automated classification of fresh tea leaves improves resource utilization and reduces manual picking costs. The present study proposes a method based on an improved genetic algorithm for identifying fresh tea leaves in high-speed parabolic motion using the phenotypic characteristics of the leaves. During parabolic flight, light is transmitted through the tea leaves, and six types of fresh tea leaves can be quickly identified by a camera. RESULTS: The influence of combinations of morphology, color, and custom corner-point morphological features on the classification results were investigated, and the necessary dimensionality of the model was tested. After feature selection and combination, the classification performance of the Naive Bayes, k-nearest neighbor, and support vector machine algorithms were compared. The recognition time of Naive Bayes was the shortest, whereas the accuracy of support vector machine had the best classification accuracy at approximately 97%. The support vector machine algorithm with only three feature dimensions (equivalent diameter, circularity, and skeleton endpoints) can meet production requirements with an accuracy rate reaching 92.5%. The proposed algorithm was tested by using the Swedish leaf and Flavia data sets, on which it achieved accuracies of 99.57% and 99.44%, respectively, demonstrating the flexibility and efficiency of the recognition scheme detailed in the present study. CONCLUSION: This research provides an efficient tea leaves recognition system that can be applied to production lines to reduce manual picking costs. © 2022 Society of Chemical Industry.


Assuntos
Algoritmos , Máquina de Vetores de Suporte , Teorema de Bayes , Folhas de Planta , Chá
5.
Entropy (Basel) ; 24(3)2022 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35327884

RESUMO

In this paper, we present a new method for the construction of maximally entangled states in Cd⊗Cd' when d'≥2d. A systematic way of constructing a set of maximally entangled bases (MEBs) in Cd⊗Cd' was established. Both cases when d' is divisible by d and not divisible by d are discussed. We give two examples of maximally entangled bases in C2⊗C4, which are mutually unbiased bases. Finally, we found a new example of an unextendible maximally entangled basis (UMEB) in C2⊗C5.

6.
BMC Cancer ; 21(1): 747, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34187415

RESUMO

BACKGROUND: The molecular pathogenesis of endometrial cancer is not completely understood. CypB upregulated in many cancers, however, its role in endometrial carcinoma has not been studied. Here, we determine the effect of CypB on the growth of endometrial cancer. METHODS: In this study, we examined the expression of CypB in endometrial cancer tissues using immunohistochemistry. CypB silenced in HEC-1-B cell line by shRNA. CCK-8, colony formation assays, wound healing assays, and transwell analysis were performed to assess its effect on tumor cell proliferation and metastasis. Furthermore, microarray analysis was carried out to compare the global mRNA expression profile between the HEC-1-B and CypB-silenced HEC-1-B cells. Gene ontology and KEGG pathway enrichment analysis were performed to determine the potential function of differentially expressed genes related to CypB. RESULTS: We found that CypB was upregulated in endometrial cancer, inhibit CypB expression could significantly suppress cell proliferation, metastasis, and migration. We identified 1536 differentially expressed genes related to CypB (onefold change, p < 0.05), among which 652 genes were upregulated and 884 genes were downregulated. The genes with significant difference in top were mainly enriched in the cell cycle, glycosphingolipid biosynthesis, adherens junctions, and metabolism pathways. CONCLUSION: The results of our study suggest that CypB may serve as a novel regulator of endometrial cell proliferation and metastasis, thus representing a novel target for gene-targeted endometrial therapy. TRIAL REGISTRATION: YLYLLS [2018] 008. Registered 27 November 2017.


Assuntos
Neoplasias do Endométrio/genética , Proliferação de Células , Ciclofilinas/genética , Feminino , Humanos , Metástase Neoplásica
7.
J Sci Food Agric ; 100(10): 3803-3811, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32201954

RESUMO

BACKGROUND: The quality of fresh tea leaves after harvest determines, to some extent, the quality and price of commercial tea. A fast and accurate method to evaluate the quality of fresh tea leaves is required. RESULTS: In this study, the potential of hyperspectral imaging in the range of 328-1115 nm for the rapid prediction of moisture, total nitrogen, crude fiber contents, and quality index value was investigated. Ninety samples of eight tea-leaf varieties and two picking standards were tested. Quantitative partial least squares regression (PLSR) models were established using a full spectrum, whereas multiple linear regression (MLR) models were developed using characteristic wavelengths selected by a successive projections algorithm (SPA) and competitive adaptive reweighted sampling. The results showed that the optimal SPA-MLR models for moisture, total nitrogen, crude fiber contents, and quality index value yielded optimal performance with coefficients of determination for prediction (R2 p) of 0.9357, 0.8543, 0.8188, 0.9168; root mean square error of 0.3437, 0.1097, 0.3795, 1.0358; and residual prediction deviation of 4.00, 2.56, 2.31, and 3.51, respectively. CONCLUSION: The results suggested that the hyperspectral imaging technique coupled with chemometrics was a promising tool for the rapid and nondestructive measurement of tea-leaf quality, and had the potential to develop multispectral imaging systems for future online detection of tea-leaf quality. © 2020 Society of Chemical Industry.


Assuntos
Camellia sinensis/química , Imageamento Hiperespectral/métodos , Folhas de Planta/química , Camellia sinensis/classificação , Nitrogênio/análise , Folhas de Planta/classificação , Controle de Qualidade
8.
J Sci Food Agric ; 100(1): 161-167, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31471904

RESUMO

BACKGROUND: Rapid and accurate diagnosis of nitrogen (N) status in field crops is of great significance for site-specific N fertilizer management. This study aimed to evaluate the potential of hyperspectral imaging coupled with chemometrics for the qualitative and quantitative diagnosis of N status in tea plants under field conditions. RESULTS: Hyperspectral data from mature leaves of tea plants with different N application rates were preprocessed by standard normal variate (SNV). Partial least squares discriminative analysis (PLS-DA) and least squares-support vector machines (LS-SVM) were used for the classification of different N status. Furthermore, partial least squares regression (PLSR) was used for the prediction of N content. The results showed that the LS-SVM model yielded better performance with correct classification rates of 82% and 92% in prediction sets for the diagnosis of different N application rates and N status, respectively. The PLSR model for leaf N content (LNC) showed excellent performance, with correlation coefficients of 0.924, root mean square error of 0.209, and residual predictive deviation of 2.686 in the prediction set. In addition, the important wavebands of the PLSR model were interpreted based on regression coefficients. CONCLUSION: Overall, our results suggest that the hyperspectral imaging technique can be an effective and accurate tool for qualitative and quantitative diagnosis of N status in tea plants. © 2019 Society of Chemical Industry.


Assuntos
Camellia sinensis/química , Nitrogênio/análise , Análise Espectral/métodos , Camellia sinensis/metabolismo , Fertilizantes/análise , Análise dos Mínimos Quadrados , Nitrogênio/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Máquina de Vetores de Suporte
9.
J Xray Sci Technol ; 28(1): 137-145, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31868728

RESUMO

Noninvasive extraction of tissue conductivity distribution is important in brain imaging and cancer detection. Here we present an improved method that can accurately image tissue conductivity using tomographically measured microwave-induced thermoacoustic data. Our reconstruction algorithm is first tested using simulations, and then validated using tissue phantom experiments where saline-containing tubes are used as target(s) with various target sizes, positions and conductivities. The average error of reconstruction for the simulations is reduced from 4.87% to 1.38% compared with the previous algorithm. The experimental results obtained suggest that accurate quantitative thermoacoustic imaging would provide a potential tool for precision medicine.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento de Micro-Ondas , Estudos de Avaliação como Assunto , Humanos , Imagens de Fantasmas
10.
Wei Sheng Yan Jiu ; 49(5): 795-801, 2020 Sep.
Artigo em Zh | MEDLINE | ID: mdl-33070827

RESUMO

OBJECTIVE: To study effect of nano-selenium and nano-cerium(nano cerium oxide) on the spermatogenic ability of mice irradiated by 1800 MHz microwave radiation(MR). METHODS: Forty-two ICR mice were randomly divided into groups: blank control group, solvent control group, microwave radiation model group, low, medium and high dose groups of nano-selenium+nano-cerium. In joint effects groups of nano-selenium and nano-cerium, the nano-selenium solution(60, 120 and 240 µg/kg) and the nano-cerium oxide solution(15, 30, 60 µg/kg) were administered to the stomach at 7:30 in the morning and 18:30 in the evening, respectively. The blank control group was orally administered with an equal volume of distilled water, and the solvent control group and the MR group were orally administered with an equal volume of carboxymethylcellulose sodium solution. During the second week of gastric administration, the mice were exposed to microwave radiation(1800 MHz) for 2 h every day(specific absorption ratio: 0. 2986 W/kg). After MR treatment, the daily sperm production of testis, sperm motility and sperm deformity rate in epididymis were measured, and the testicular marker enzymes [G6 PDH(6-phosphatedehydrogenase), ACP(acid phosphatase), LDH(lactate dehydrogenase)], antioxidant indexes [CAT(catalase), MDA(malondialdehyde) and T-AOC(total antioxidant capacity)] in testicular tissue were analyzed. RESULTS: Compared with the solvent control group, MR led to the decrease of sperm motility and the increase of sperm deformity rate, decreased the enzymes activities of G6 PDH, ACP and CAT, increased LDH activity and MDA content, and decreased the T-AOC level in testicular tissue, and the differences were statistically significant(P<0. 05). Compared with the MR group, the joint action of nano-selenium and nano-cerium with medium dose increased the daily sperm production of testis((18. 98±1. 27) ×10~6/g) vs. (15. 53±1. 24) ×10~6/g), decreased the sperm deformity rate(11. 74%±0. 91% vs. 16. 84%±2. 05%), and the joint action of nano-selenium and nano-cerium with medium and high dose increased the sperm motility in epididymis(61. 98%±6. 33%, 54. 17±4. 38 vs. 45. 16%±5. 01%), and the differences were statistically significant(P<0. 05). Compared with the MR group, the joint action of nano-selenium and nano-cerium with low and medium dose increased the activity of ACP(11. 07±0. 98, 14. 85±1. 39 vs. 8. 72±0. 91 nmol/(min·mg prot), P<0. 05). The joint action of nano-selenium and nano-cerium with medium and high dose increased the activity of G6 PDH(24. 12±2. 06, 21. 36±3. 65 vs. 15. 11±1. 73 nmol/(min·mg prot), P<0. 05) and decreased the activity of LDH(15. 52±1. 17, 13. 51±1. 68 vs. 22. 46±2. 01 nmol/(min·mg prot), P<0. 05). The joint action of nano-selenium and nano-cerium with medium dose increased the activity of CAT(17. 92±2. 03 vs. 11. 69±0. 87 nmol/(min·mg prot), P<0. 05) and decreased the content of MDA(5. 17 ±0. 62 vs. 9. 03 ±0. 63 nmol/mg prot, P<0. 05). The joint action of nano-selenium and nano-cerium with low, medium and high dose increased the level of T-AOC(22. 06±1. 54, 29. 36±2. 39, 21. 01±2. 47 vs. 12. 88±1. 82 U/mg prot, P<0. 05). CONCLUSION: The joint addition of nano-selenium and nano-cerium can improve the reproductive function of male mice exposed to MR, and can effectively alleviate the changes of mouse testicular marker enzyme activity and the decline of antioxidant capacity caused by MR.


Assuntos
Selênio , Animais , Antioxidantes , Humanos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Micro-Ondas , Motilidade dos Espermatozoides
11.
Planta ; 249(2): 363-376, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30209617

RESUMO

MAIN CONCLUSION: A normal tea plant with one albino branch was discovered. RNA sequencing, albinism phenotype and ultrastructural observations provided a valuable understanding of the albino mechanism in tea plants. Tea plants with a specific color (white or yellow) have been studied extensively. A normal tea plant (Camellia sinensis cv. quntizhong) with one albino branch was discovered in a local tea plantation in Huangshan, Anhui, China. The pure albino leaves on this special branch had accumulated a fairly high content of amino acids, especially theanine (45.31 mg/g DW), and had a low concentration of polyphenols and an extremely low chlorophyll (Chl) content compared with control leaves. Ultrastructural observation of an albino leaf revealed no chloroplasts, whereas it was viable in the control leaf. RNA sequencing and differentially expressed gene (DEG) analysis were performed on the albino leaves and on control leaves from a normal green branch. The related genes involved in theanine and polyphenol biosynthesis were also investigated in this study. DEG expression patterns in Chl biosynthesis or degradation, carotenoid biosynthesis or degradation, chloroplast development, and biosynthesis were influenced in the albino leaves. Chloroplast deletion in albino leaves had probably destroyed the balance of carbon and nitrogen metabolism, leading to a high accumulation of free amino acids and a low concentration of polyphenols in the albino leaves. The obtained results can provide insight into the mechanism underlying this special albino branch phenotype, and are a valuable contribution toward understanding the albino mechanism in tea plants.


Assuntos
Aminoácidos/metabolismo , Camellia sinensis/metabolismo , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Polifenóis/metabolismo
12.
Plant Biotechnol J ; 17(10): 1938-1953, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30913342

RESUMO

Tea is the world's widely consumed nonalcohol beverage with essential economic and health benefits. Confronted with the increasing large-scale omics-data set particularly the genome sequence released in tea plant, the construction of a comprehensive knowledgebase is urgently needed to facilitate the utilization of these data sets towards molecular breeding. We hereby present the first integrative and specially designed web-accessible database, Tea Plant Information Archive (TPIA; http://tpia.teaplant.org). The current release of TPIA employs the comprehensively annotated tea plant genome as framework and incorporates with abundant well-organized transcriptomes, gene expressions (across species, tissues and stresses), orthologs and characteristic metabolites determining tea quality. It also hosts massive transcription factors, polymorphic simple sequence repeats, single nucleotide polymorphisms, correlations, manually curated functional genes and globally collected germplasm information. A variety of versatile analytic tools (e.g. JBrowse, blast, enrichment analysis, etc.) are established helping users to perform further comparative, evolutionary and functional analysis. We show a case application of TPIA that provides novel and interesting insights into the phytochemical content variation of section Thea of genus Camellia under a well-resolved phylogenetic framework. The constructed knowledgebase of tea plant will serve as a central gateway for global tea community to better understand the tea plant biology that largely benefits the whole tea industry.


Assuntos
Camellia sinensis/genética , Biologia Computacional , Genoma de Planta , Genômica , Filogenia , Chá
13.
Opt Lett ; 44(7): 1876-1879, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30933170

RESUMO

Taking advantage of the high thermal conductivity of graphene, this Letter demonstrates a microelectromechanical (MEM) tunable Fabry-Pérot (F-P) cavity, based on a graphene-bonded fiber device (GFD), which acts as a microheater. By increasing the electric current from 0 to 8 mA in the heater, the temperature of the GFD can rise and approach a value of 760 K theoretically. This high temperature will cause a deformation of the fiber, allowing the graphene-bonded fiber end to form a gap-adjustable F-P cavity with a cleaved single-mode fiber. The gap in the cavity can be reduced by increasing the current applied, leading the transmittance of the cavity to change. In this work, a highly sensitive current sensor (5.9×105 nm/A2) and a tunable mode-locked fiber laser (1.2×104 nm/A2) are created based on the MEM tunable F-P cavity.

14.
J Sci Food Agric ; 99(5): 2596-2601, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30411367

RESUMO

BACKGROUND: Confirmation of food labeling that claims production in a small geographic region is critical to traceability, quality control and brand protection. In the current study, isotope ratio mass spectrometry (IRMS) was used to generate profiles of δ13 C and δ15 N to determine if the stable isotope signatures of Keemun black tea differ within the three counties that claim production. Other factors (cultivar type, leaf maturity and manufacturing process) were considered for their potential effects. RESULTS: Both cultivar type and leaf maturity have remarkable impact on the δ15 N values of tea leaves, and that the cultivar influenced the δ13 C values. Keemun black tea from Qimen county could be easily discriminated from samples from Dongzhi and Guichi counties based on δ15 N signatures. The k-NN model was cross-validated with an accuracy of 91.6%. Environmental factors and/or genotype seem to be the major reasons for δ15 N differences in Keemun black tea from the selected regions. CONCLUSION: This article provides a potential effective method to delineate the geographic point-of-origin of Keemun black tea based on δ15 N signatures. © 2018 Society of Chemical Industry.


Assuntos
Camellia sinensis/química , Espectrometria de Massas/métodos , Isótopos de Nitrogênio/análise , Chá/química , Isótopos de Carbono/análise , Análise Discriminante
15.
Wei Sheng Yan Jiu ; 48(3): 482-487, 2019 May.
Artigo em Zh | MEDLINE | ID: mdl-31133139

RESUMO

OBJECTIVE: To study the chronotoxicity of radio-frequency radiation(RF) on the plasma stress hormones and immune factors in mice. METHODS: A total of 72 healthy C57 BL mice with circadian rhythm were divided into twelve groups: 6 Sham group and 6 RF groups. RF groups were exposed to 1.8 GHz RF at 226 µW/cm~2 for 60 days with 2 h/day respectively at corresponding zeitgeber time(ZT 0:00, ZT 4:00, ZT 8:00, ZT 12:00, ZT 16:00, ZT 20:00). The Sham group mice were exposed to the same condition without electromagnetic signal. At the end of last RF exposure, blood samples were collected from each animal. The concentrations of plasma stress hormones(ACTH, CORT) and immune factors(GM-CSF, TNF-α) were determined by enzyme linked immunosorbent assay(ELISA) method. RESULTS: The daily average levels of ACTH, CORT, GM-CSF and TNF-α were 84.12, 60.14, 1112.02 and 594.49 ng/L, which were decreased to 62.07, 41.21, 84.18 and 305.08 ng/L after 60 days of RF exposure. Compared to sham-exposed animals, the daily average levels of ACTH, CORT, GM-CSF and TNF-α were all significantly decreased(P<0.05). Circadian rhythms in the secreting of CORT, GM-CSF, TNF-α were disappeared(P>0.05), circadian rhythms of ACTH was shifted in RF-exposed mice, with the amplitude reduced from 12.45 to 4.88 and peak time postponed from 1:39 to 5:29. CONCLUSION: 1.8 GHz RF may weaken the function of stress and immune, and disturb their circadian rhythmicities.


Assuntos
Ritmo Circadiano , Ondas de Rádio , Animais , Fatores Imunológicos , Camundongos
16.
J Org Chem ; 83(12): 6815-6823, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29771519

RESUMO

The chiral Co(III)-complex-templated Brønsted acids were found to be efficient bifunctional phase-transfer catalysts for the highly enantioselective bromocyclization of protected tryptamines with readily available N-bromosuccinimide (NBS) under an air atmosphere. The 3-bromohexahydropyrrolo[2,3- b]indoles, which are key building blocks of cyclotryptamine alkaloids, were thus obtained in up to 95% yield and 93.5:6.5 er.

17.
Int J Mol Sci ; 17(1)2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26742036

RESUMO

Tea plant is known to be a hyper-accumulator of fluoride (F). Over-intake of F has been shown to have adverse effects on human health, e.g., dental fluorosis. Thus, understanding the mechanisms fluoride accumulation and developing potential approaches to decrease F uptake in tea plants might be beneficial for human health. In the present study, we found that pretreatment with the anion channel inhibitor NPPB reduced F accumulation in tea plants. Simultaneously, we observed that NPPB triggered Ca(2+) efflux from mature zone of tea root and significantly increased relative CaM in tea roots. Besides, pretreatment with the Ca(2+) chelator (EGTA) and CaM antagonists (CPZ and TFP) suppressed NPPB-elevated cytosolic Ca(2+) fluorescence intensity and CaM concentration in tea roots, respectively. Interestingly, NPPB-inhibited F accumulation was found to be significantly alleviated in tea plants pretreated with either Ca(2+) chelator (EGTA) or CaM antagonists (CPZ and TFP). In addition, NPPB significantly depolarized membrane potential transiently and we argue that the net Ca(2+) and H⁺ efflux across the plasma membrane contributed to the restoration of membrane potential. Overall, our results suggest that regulation of Ca(2+)-CaM and plasma membrane potential depolarization are involved in NPPB-inhibited F accumulation in tea plants.


Assuntos
Cálcio/metabolismo , Calmodulina/metabolismo , Camellia sinensis/efeitos dos fármacos , Fluoretos/metabolismo , Bombas de Íon/antagonistas & inibidores , Nitrobenzoatos/farmacologia , Proteínas de Plantas/metabolismo , Camellia sinensis/citologia , Camellia sinensis/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Raízes de Plantas/citologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo
18.
J Asian Nat Prod Res ; 17(7): 767-71, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25630942

RESUMO

Two new sesquiterpenoids (phellinuins H and I), together with five known compounds, were isolated from cultures of mushroom Phellinus sp. Their structures were elucidated based on comparison of nuclear magnetic resonance and MS data and those reported in the literature. All of these compounds were tested for cytotoxicity against five cancer cell lines (HL-60, SMMC-721, A-549, MCF-7, and SW-480).


Assuntos
Basidiomycota/química , Sesquiterpenos/isolamento & purificação , China , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células HL-60 , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Sesterterpenos
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(12): 3422-6, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-26964222

RESUMO

Tea is one of the most popular beverages in the world. For the contribution to the taste and healthy functions of tea, amino acids and catechins are important components. Among different kinds of black teas in the world, Keemun black tea has the famous and specific fragrance, "Keemun aroma". During the processing procedure of Keemun black tea, the contents of amino acids and catechins changed greatly, and the differences of these concentrations during processing varied significantly. However, a rapid and dynamic determination method during the processing procedure was not existed up to now. In order to find out a rapid determination method for the contents of amino acids and catechins during the processing procedure of Keemun black tea, the materials of fresh leaves, withered leaves, twisted leaves, fermented leaves, and crude tea (after drying) were selected to acquire their corresponding near infrared spectroscopy and obtain their contents of amino acids and catechins by chemical analysis method. The original spectra data were preprocessed by the Standard Normal Variate Transformation (SNVT) method. And the model of Near Infrared (NIR) spectroscopy with the contents of amino acids and catechins combined with Synergy Interval Partial Least squares (Si-PLS) was established in this study. The correlation coefficients and the cross validation root mean square error are treated as the efficient indexes for evaluating models. The results showed that the optimal prediction model of amino acids by Si-PLS contained 20 spectral intervals combined with 4 subintervals and 9 principal component factors. The correlation coefficient and the root mean square error of the calibration set were 0. 955 8 and 1. 768, respectively; the correlation coefficient and the root mean square error of the prediction set were 0. 949 5 and 2. 16, respectively. And the optimal prediction model of catechins by Si-PLS contained 20 spectral intervals combined with 3 subintervals and 10 principal component factors. The correlation coefficient and the root mean square error of the calibration set were 0. 940 1 and 1. 22, respectively; the correlation coefficient and the root mean square error of the prediction set were 0. 938 5 and 1. 17, respectively. The results showed that the established models had good accuracy which could provide a theoretical foundation for the online determination of tea chemical components during processing.


Assuntos
Aminoácidos/química , Catequina/química , Chá/química , Camellia sinensis/química , Fermentação , Análise dos Mínimos Quadrados , Modelos Teóricos , Folhas de Planta/química , Espectroscopia de Luz Próxima ao Infravermelho
20.
BMC Plant Biol ; 14: 243, 2014 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-25224438

RESUMO

BACKGROUND: Tea is one of the most consumed beverages worldwide. The healthy effects of tea are attributed to a wealthy of different chemical components from tea. Thousands of studies on the chemical constituents of tea had been reported. However, data from these individual reports have not been collected into a single database. The lack of a curated database of related information limits research in this field, and thus a cohesive database system should necessarily be constructed for data deposit and further application. DESCRIPTION: The Tea Metabolome database (TMDB), a manually curated and web-accessible database, was developed to provide detailed, searchable descriptions of small molecular compounds found in Camellia spp. esp. in the plant Camellia sinensis and compounds in its manufactured products (different kinds of tea infusion). TMDB is currently the most complete and comprehensive curated collection of tea compounds data in the world. It contains records for more than 1393 constituents found in tea with information gathered from 364 published books, journal articles, and electronic databases. It also contains experimental 1H NMR and 13C NMR data collected from the purified reference compounds or collected from other database resources such as HMDB. TMDB interface allows users to retrieve tea compounds entries by keyword search using compound name, formula, occurrence, and CAS register number. Each entry in the TMDB contains an average of 24 separate data fields including its original plant species, compound structure, formula, molecular weight, name, CAS registry number, compound types, compound uses including healthy benefits, reference literatures, NMR, MS data, and the corresponding ID from databases such as HMDB and Pubmed. Users can also contribute novel regulatory entries by using a web-based submission page. The TMDB database is freely accessible from the URL of http://pcsb.ahau.edu.cn:8080/TCDB/index.jsp. The TMDB is designed to address the broad needs of tea biochemists, natural products chemists, nutritionists, and members of tea related research community. CONCLUSION: The TMDB database provides a solid platform for collection, standardization, and searching of compounds information found in tea. As such this database will be a comprehensive repository for tea biochemistry and tea health research community.


Assuntos
Bases de Dados Factuais , Chá/química , Metaboloma , Interface Usuário-Computador
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