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1.
Plant Dis ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38411666

RESUMO

Bletilla striata is a valuable medicine in China, belonging to the Orchidaceae family, and is used for treating various ailments such as hemoptysis, pyocutaneous disease, and anal fissure by preventing blood flow, reducing swelling, and promoting granulation. In June 2022, a disease with symptoms similar to root rot was observed on B. striata in the pineland (the area was 0.4 hectare) of Lancang County (22°48'17" N, 99°46'58"22 E), Yunnan Province, China. The root rot incidence rate reached 16% (Table S1). The root rot incidence was calculated as follows: root rot incidence (%) = (number of root rot seedlings/total number of seedlings investigated) × 100. In May 2023, the similar symptoms were observed in the field, and the disease incidence was 17% (Table S1). Initially, there were no obvious symptoms on the leaves. Subsequently, the leaves wilted and brown spots appeared. Later, the entire leaf browned, withered and eventually died (Fig. S1A, B). The roots were brown and the browning spread from the root edge to the center, causing vascular bundle browning and dead lignified fibers in the cortex (Fig. S1C, D). To isolate the causal pathogen, 20 symptomatic root tissues were collected from 20 plants. Cutting the diseased tissues into small pieces (0.5 × 0.5 cm). After surface sterilization (30s with 75% ethanol and 3 min with 2% sodium hypochlorite, rinsed three times with sterile water), the disinfected root tissues were plated onto potato dextrose agar (PDA) and incubated at 25℃ for 4 to 6 days with 12 h light/dark photoperiod. A total of 10 single-spore isolates with similar morphology and conidial characteristics were obtained. one representative isolate BJG6 was selected for identification and further study. The fungal colony was reddish-brown or orange-white on PDA after 8 days of incubation at 25℃. The mycelium was like carpet or cotton, and the edge of colony was uniform (Fig. S1E). Large conidia were formed on simple conidial peduncles (Fig. S1F, G). The conidia with 1~3 septates and 1 mostly, with cylindrical shapes and narrow tops but sharp bases (Fig. S1H-J). Conidia with 1 septate measured as 5.5 (4.3-6.7) × 20.7 (16.0-25.4) µm (n=30), while those with 2 septates measured as 6.6 (5.8-7.4) × 26.5 (21.7-31.3) µm (n=30), and those with 3 septates was 6.9 (6.2-7.8) × 31.8 (29.3-34.3) µm (n=30). Ellipsoidal microconidia could be formed on conidiophore and measured as 2.4 (1.9-2.9) × 4.9 (5.9-3.9) µm to 2.7 (2.2-3.2) × 5.4 (4.3-6.5) µm (n=30). Spherical or subspherical chlamydospores were produced on low-nutrient agar, with an average size of 5.8(5.0-6.6) µm×5.3 (4.4-6.2) µm (n=30) (Fig. S1K, L). According to the morphology and conidial features, the pathogen was consistent with the description of Ilyonectria coprosmae (Cabral et al. 2012). The total genomic DNA was extracted, and primer pairs ITS4/ITS5 were used to amplify and sequence the rDNA-ITS region (ITS1-5.8 S rRNA-ITS2 gene regions) (White et al. 1990). The sequences were deposited in GenBank (SUB13905750 for ITS). BLAST searches revealed BJG6 showed 98% homology with corresponding sequences of Ilyonectria coprosmae in GenBank (JF735260). A phylogenetic tree (MEGA 7.0) was constructed using maximum-likelihood methods (Fig. S2). To identify pathogenicity, a cultured medium in a size of 6mm containing isolate BJG6 was inoculated onto ten healthy roots of B. striata, PDA plugs alone were used as the uninoculated controls. All samples were placed in a dark inoculation chamber at 25℃. The pathogenicity test was replicated three times. After two weeks, all inoculated roots appeared similar symptoms identical to those observed on field plants (Fig. S1M, N-P), while control plants remained healthy (Fig. S1Q, R). The same pathogenic fungus was reisolated from the symptomatic root rot, and the characteristics of colony and conidia were the same as the original isolates (Fig. S1S, T). These results confirmed I. coprosmae as the causal pathogen of root rot disease on B. striata in China by Koch's postulates tests for the first time. Further exploration should be conducted to understand the occurrence and migration of this disease, so as to develop specific and efficient disease management strategies in the future.

2.
Nano Lett ; 23(18): 8585-8592, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37669044

RESUMO

Single-atom nanozymes (SAzymes) open new possibilities for the development of artificial enzymes that have catalytic activity comparable to that of natural peroxidase (POD). So far, most efforts have focused on the structural modulation of the Fe-N4 moiety to mimic the metalloprotein heme center. However, non-heme-iron POD with much higher activity, for example, HppE, has not been mimicked successfully due to its structural complexity. Herein, carbon dots (CDs)-supported SAzymes with twisted, nonplanar Fe-O3N2 active sites, highly similar to the non-heme iron center of HppE, was synthesized by exploiting disordered and subnanoscale domains in CDs. The Fe-CDs exhibit an excellent POD activity of 750 units/mg, surpassing the values of conventional SAzymes with planar Fe-N4. We further fabricated an activatable Fe-CDs-based therapeutic agent with near-infrared enhanced POD activity, a photothermal effect, and tumor-targeting ability. Our results represent a big step in the design of high-performance SAzymes and provide guidance for future applications for synergistic tumor therapy.

3.
Genomics ; 113(1 Pt 1): 159-170, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33253793

RESUMO

To comprehensively annotate miRNAs and their targets in tea plant, Camellia sinensis, we sequenced small and messenger RNAs of 9 samples of Camellia sinensis var. assamica (YK-10), a diploid elite cultivar widely grown in southwest China. In order to identify targets of miRNAs, we sequenced two degradome sequencing profiles from leaves and roots of YK-10, respectively. By analyzing the small RNA-Seq profiles, we newly identified 137 conserved miRNAs and 23 species specific miRNAs in the genome of YK-10, which significantly improved the annotation of miRNAs in tea plant. Approximately 2000 differently expressed genes were identified when comparing RNA-Seq profiles of any two of the three organs selected in the study. Totally, more than 5000 targets of conserved miRNAs were identified in the two degradome profiles. Furthermore, our results suggest that a few miRNAs play roles in the biosynthesis pathways of theanine, caffeine and flavonoid. These results enhance our understanding of small RNA guided gene regulations in different organs of tea plant.


Assuntos
Camellia sinensis/genética , Redes Reguladoras de Genes , MicroRNAs/genética , Camellia sinensis/classificação , Evolução Molecular , MicroRNAs/metabolismo , Filogenia , Componentes Aéreos da Planta/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Metabolismo Secundário/genética
4.
Mikrochim Acta ; 188(4): 141, 2021 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-33774694

RESUMO

A redox-responsive chemodynamic therapy (CDT)-based theranostic system composed of hollow mesoporous MnO2 (H-MnO2), doxorubicin (DOX), and fluorescent (FL) carbon nanodots (CDs) is reported for the diagnosis and therapy of cancer. In general, since H-MnO2 can be degraded by intracellular glutathione (GSH) to form Mn2+ with excellent Fenton-like activity to generate highly reactive ·OH, the normal antioxidant defense system can be injured via consumption of GSH. This in turn can potentiate the cytotoxicity of CDT and release DOX. The cancer cells can be eliminated effectively by the nanoplatform via the synergistic effect of chemotherapy and CDT. The FL of CDs can be restored after H-MnO2 is degraded which blocked the fluorescence resonance energy transfer process between CDs as an energy donor and H-MnO2 as an FL acceptor. The GSH can be determined by recovery of the FL and limit of detection is 1.30 µM with a linear range of 0.075-0.825 mM. This feature can be utilized to efficiently distinguish cancerous cells from normal ones based on different GSH concentrations in the two types of cells. As a kind of CDT-based theranostic system responsive to GSH, simultaneously diagnostic (normal/cancer cell differentiation) and therapeutic function (chemotherapy and CDT) in a single nanoplatform can be achieved. The redox-responsive chemodynamic therapy (CDT)-based theranostic system is fabricated by H-MnO2, DOX, and fluorescent CDs. The nanoplatform can realize simultaneously diagnostic (normal/cancer cell differentiation) and therapeutic function (chemotherapy and CDT) to improve the therapeutic efficiency and security.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Corantes Fluorescentes/química , Glutationa/análise , Medicina de Precisão/métodos , Pontos Quânticos/química , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Carbono/química , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Doxorrubicina/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Tratamento Farmacológico , Humanos , Limite de Detecção , Camundongos , Molibdênio/química , Neoplasias/diagnóstico , Óxidos/química , Espectrometria de Fluorescência
5.
Mikrochim Acta ; 188(5): 154, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33821295

RESUMO

Mitochondria, as the energy factory of most cells, are not only responsible for the generation of adenosine triphosphoric acid (ATP) but also essential targets for therapy and diagnosis of various diseases, especially cancer. The safe and potential nanoplatform which can deliver various therapeutic agents to cancer cells and mitochondrial targeted imaging is urgently required. Herein, Au nanoparticles (AuNPs), mesoporous silica nanoparticles (MSN), cationic ligand (triphenylphosphine (TPP)), doxorubicin (DOX), and carbon nanodots (CDs) were utilized to fabricate mitochondrial targeting drug delivery system (denoted as CDs(DOX)@MSN-TPP@AuNPs). Since AuNPs, as the gatekeepers, can be etched by intracellular glutathione (GSH) via ligand exchange induced etching process, DOX can be released into cells in a GSH-dependent manner which results in the superior GSH-modulated tumor inhibition activity. Moreover, after etching by GSH, the CDs(DOX)@MSN-TPP@AuNPs can serve as promising fluorescent probe (λex = 633 nm, λem = 650 nm) for targeted imaging of mitochondria in living cells with near-infrared fluorescence. The induction of apoptosis derived from the membrane depolarization of mitochondria is the primary anti-tumor route of CDs(DOX)@MSN-TPP@AuNPs. As a kind of GSH-responsive mitochondrial targeting nanoplatform, it holds great promising for effective cancer therapy and mitochondrial targeted imaging. The mitochondrial targeting drug delivery system was fabricated by AuNPs, MSN, TPP, and CDs. The nanoplatform can realize redox-responsive drug delivery and targeted imaging of mitochondria in living cells to improve the therapeutic efficiency and security.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Corantes Fluorescentes/química , Nanopartículas Metálicas/química , Mitocôndrias/metabolismo , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Carbono/química , Carbono/toxicidade , Linhagem Celular Tumoral , Doxorrubicina/química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Corantes Fluorescentes/toxicidade , Glutationa/metabolismo , Ouro/química , Ouro/toxicidade , Humanos , Nanopartículas Metálicas/toxicidade , Camundongos , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Compostos Organofosforados/química , Compostos Organofosforados/toxicidade , Pontos Quânticos/química , Pontos Quânticos/toxicidade , Dióxido de Silício/química , Dióxido de Silício/toxicidade , Prata/química , Prata/toxicidade
6.
BMC Genomics ; 19(Suppl 9): 983, 2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-30999850

RESUMO

BACKGROUND: MicroRNAs (miRNAs) are small non-coding RNAs that play important roles by regulating other genes. Rosa rugosa Thunb. is an important ornamental and edible plant, yet there are only a few studies on the miRNAs and their functions in R. rugosa. RESULTS: We sequenced 10 samll RNA profiles from the roots, petals, pollens, stamens, and leaves and 4 RNA-seq profiles in leaves and petals to analysis miRNA, phasiRNAs and mRNAs in R. rugosa. In addition, we acquired a degradome sequencing profile from leaf of R. rugosa to identify miRNA and phasiRNA targets using the SeqTar algorithm. We have identified 321 conserved miRNA homologs including primary transcripts for 25 conserved miRNAs, and 22 novel miRNAs. We identified 592 putative targets of the conserved miRNAs or tasiRNAs that showed significant accumulations of degradome reads. We found differential expression patterns of conserved miRNAs in five different tissues of R. rugosa. We identified three hundred and thirty nine 21 nucleotide (nt) PHAS loci, and forty nine 24 nt PHAS loci, respectively. Our results suggest that miR482 triggers generations of phasiRNAs by targeting nucleotide-binding, leucine-rich repeat (NB-LRR) disease resistance genes in R. rugosa. Our results also suggest that the deregulated genes in leaves and petals are significantly enriched in GO terms and KEGG pathways related to metabolic processes and photosynthesis. CONCLUSIONS: These results significantly enhanced our knowledge of the miRNAs and phasiRNAs, as well as their potential functions, in R. rugosa.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , MicroRNAs/genética , Proteínas de Plantas/genética , RNA de Plantas/genética , RNA Interferente Pequeno/genética , Rosa/genética , Biologia Computacional , Regulação da Expressão Gênica de Plantas , Folhas de Planta/genética
7.
Hepatology ; 68(2): 496-514, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29457836

RESUMO

Alcoholic liver disease (ALD) is characterized by lipid accumulation and liver injury. However, how chronic alcohol consumption causes hepatic lipid accumulation remains elusive. The present study demonstrates that activation of the mechanistic target of rapamycin complex 1 (mTORC1) plays a causal role in alcoholic steatosis, inflammation, and liver injury. Chronic-plus-binge ethanol feeding led to hyperactivation of mTORC1, as evidenced by increased phosphorylation of mTOR and its downstream kinase S6 kinase 1 (S6K1) in hepatocytes. Aberrant activation of mTORC1 was likely attributed to the defects of the DEP domain-containing mTOR-interacting protein (DEPTOR) and the nicotinamide adenine dinucleotide-dependent deacetylase sirtuin 1 (SIRT1) in the liver of chronic-plus-binge ethanol-fed mice and in the liver of patients with ALD. Conversely, adenoviral overexpression of hepatic DEPTOR suppressed mTORC1 signaling and ameliorated alcoholic hepatosteatosis, inflammation, and acute-on-chronic liver injury. Mechanistically, the lipid-lowering effect of hepatic DEPTOR was attributable to decreased proteolytic processing, nuclear translocation, and transcriptional activity of the lipogenic transcription factor sterol regulatory element-binding protein-1 (SREBP-1). DEPTOR-dependent inhibition of mTORC1 also attenuated alcohol-induced cytoplasmic accumulation of the lipogenic regulator lipin 1 and prevented alcohol-mediated inhibition of fatty acid oxidation. Pharmacological intervention with rapamycin alleviated the ability of alcohol to up-regulate lipogenesis, to down-regulate fatty acid oxidation, and to induce steatogenic phenotypes. Chronic-plus-binge ethanol feeding led to activation of SREBP-1 and lipin 1 through S6K1-dependent and independent mechanisms. Furthermore, hepatocyte-specific deletion of SIRT1 disrupted DEPTOR function, enhanced mTORC1 activity, and exacerbated alcoholic fatty liver, inflammation, and liver injury in mice. CONCLUSION: The dysregulation of SIRT1-DEPTOR-mTORC1 signaling is a critical determinant of ALD pathology; targeting SIRT1 and DEPTOR and selectively inhibiting mTORC1-S6K1 signaling may have therapeutic potential for treating ALD in humans. (Hepatology 2018).


Assuntos
Fígado Gorduroso Alcoólico/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipogênese/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Animais , Etanol/farmacologia , Fígado Gorduroso Alcoólico/patologia , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Fígado/patologia , Camundongos , Proteínas Nucleares/metabolismo , Fosfatidato Fosfatase/metabolismo , Transdução de Sinais , Sirtuína 1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Serina-Treonina Quinases TOR/metabolismo
8.
Pestic Biochem Physiol ; 123: 9-18, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26267047

RESUMO

Zoxamide is an important fungicide for oomycete disease management. In this study, we established the baseline sensitivity of Phytophthora cactorum to zoxamide and assessed the risk of developing resistance to zoxamide using ultraviolet irradiation and fungicide taming methods. All 73 studied isolates were sensitive to zoxamide, with effective concentrations for 50% inhibition of mycelial growth ranging from 0.04 to 0.29 mg/L and mean of 0.15 mg/L. Stable zoxamide-resistant mutants of P. cactorum were not obtained from four arbitrarily selected isolates by either treating mycelial cultures with ultraviolet irradiation or adapting mycelial cultures to the addition of increasing zoxamide concentrations. However, the sensitivity of the isolates to zoxamide could be easily reduced by successive zoxamide treatments. In addition to displaying decreased sensitivity to zoxamide, these isolates also showed decreased sensitivity to the fungicides flumorph and cymoxanil. Proteomic analysis indicated that some proteins involved in antioxidant detoxification, ATP-dependent multidrug resistance, and anti-apoptosis activity, are likely responsible for the induced decrease in the sensitivity of P. cactorum to zoxamide compared to controls. Further semi-quantitative PCR analysis demonstrated that the gene expression profiles of most of above proteins were consistent with the proteomic analysis. Based on the above results, P. cactorum shows low resistance risk to zoxamide; however, the fungicidal effect of zoxamide might be decreased due to induced resistance when this fungicide is continuously applied.


Assuntos
Amidas , Phytophthora/fisiologia , Proteômica , Acetamidas , Farmacorresistência Fúngica Múltipla/efeitos da radiação , Morfolinas , Raios Ultravioleta
9.
Basic Res Cardiol ; 108(5): 378, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23982491

RESUMO

Immunoglobulin light chain (LC) amyloidosis (AL) results from overproduction of circulating amyloidogenic LC proteins and subsequent amyloid fibril deposition in organs. Mortality in AL amyloidosis patients is highly associated with a rapidly progressive AL cardiomyopathy, marked by profound impairment of diastolic and systolic cardiac function and significant early mortality. While myocardial fibril deposition contributes to the severe diastolic dysfunction seen in AL cardiomyopathy patients, the degree of fibril deposition has not been found to correlate with prognosis. Previously, we and others showed a direct cardiotoxic effect of amyloidogenic LC proteins (AL-LC), which may contribute to the pathophysiology and mortality observed in AL cardiomyopathy patients. However, the mechanisms underlying AL-LC related cardiotoxicity remain unknown. Mammalian stanniocalcin1 (STC1) is associated with a number of cellular processes including oxidative stress and cell death. Herein, we find that STC1 expression is elevated in cardiac tissue from AL cardiomyopathy patients, and is induced in isolated cardiomyocytes in response to AL-LC, but not non-amyloidogenic LC. STC1 overexpression in vitro recapitulates the pathophysiology of AL-LC mediated cardiotoxicity, with increased ROS production, contractile dysfunction and cell death. Overexpression of STC1 in vivo results in significant cardiac dysfunction and cell death. Genetic silencing of STC1 prevents AL-LC induced cardiotoxicity in cardiomyocytes and protects against AL-LC induced cell death and early mortality in zebrafish. The cardiotoxic effects of STC1 appears to be mediated via mitochondrial dysfunction as indicated by loss of mitochondrial membrane potential, ROS production and increased mitochondrial calcium levels. Collectively, this work identifies STC1 as a critical determinant of AL-LC cardiotoxicity.


Assuntos
Amiloidose/metabolismo , Cardiomiopatias/metabolismo , Glicoproteínas/metabolismo , Cadeias Leves de Imunoglobulina/metabolismo , Amiloidose/patologia , Animais , Cardiomiopatias/patologia , Técnicas de Silenciamento de Genes , Humanos , Immunoblotting , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Camundongos , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Peixe-Zebra
10.
Proc Natl Acad Sci U S A ; 107(9): 4188-93, 2010 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-20150510

RESUMO

Patients with primary (AL) cardiac amyloidosis suffer from progressive cardiomyopathy with a median survival of less than 8 months and a 5-year survival of <10%. Contributing to this poor prognosis is the fact that these patients generally do not tolerate standard heart failure therapies. The molecular mechanisms underlying this deadly form of heart disease remain unclear. Although interstitial amyloid fibril deposition of Ig light chain proteins is a major cause of cardiac dysfunction in AL cardiac amyloidosis, we have previously shown that amyloid precursor proteins directly impair cardiac function at the cellular and isolated organ levels, independent of fibril formation. In this study, we report that amyloidogenic light chain (AL-LC) proteins provoke oxidative stress, cellular dysfunction, and apoptosis in isolated adult cardiomyocytes through activation of p38 mitogen-activated protein kinase (MAPK). AL-LC-induced p38 activation was found to be independent of the upstream MAPK kinase, MKK3/6, and instead depends upon transforming growth factor-beta-activated protein kinase-1 binding protein-1 (TAB1)-mediated p38alpha MAPK autophosphorylation. Treatment of cardiomyocytes with SB203580, a selective p38 MAPK inhibitor, significantly attenuated AL-LC-induced oxidative stress, cellular dysfunction, and apoptosis. Our data provide a unique mechanistic insight into the pathogenesis of AL-LC cardiac toxicity and suggest that TAB1-mediated p38alpha MAPK autophosphorylation may serve as an important event leading to cardiac dysfunction and subsequent heart failure.


Assuntos
Amiloide/fisiologia , Apoptose , Miocárdio/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Ativação Enzimática , Humanos , Imidazóis/farmacologia , Contração Miocárdica , Miocárdio/citologia , Miocárdio/enzimologia , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
11.
IEEE Trans Pattern Anal Mach Intell ; 45(4): 4964-4980, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35981064

RESUMO

Markov boundary (MB) has been widely studied in single-target scenarios. Relatively few works focus on the MB discovery for variable set due to the complex variable relationships, where an MB variable might contain predictive information about several targets. This paper investigates the multi-target MB discovery, aiming to distinguish the common MB variables (shared by multiple targets) and the target-specific MB variables (associated with single targets). Considering the multiplicity of MB, the relation between common MB variables and equivalent information is studied. We find that common MB variables are determined by equivalent information through different mechanisms, which is relevant to the existence of the target correlation. Based on the analysis of these mechanisms, we propose a multi-target MB discovery algorithm to identify these two types of variables, whose variant also achieves superiority and interpretability in feature selection tasks. Extensive experiments demonstrate the efficacy of these contributions.

12.
IEEE Trans Neural Netw Learn Syst ; 34(10): 6740-6754, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37028034

RESUMO

Recent years have witnessed the proliferation of techniques for streaming data mining to meet the demands of many real-time systems, where high-dimensional streaming data are generated at high speed, increasing the burden on both hardware and software. Some feature selection algorithms for streaming data are proposed to tackle this issue. However, these algorithms do not consider the distribution shift due to nonstationary scenarios, leading to performance degradation when the underlying distribution changes in the data stream. To solve this problem, this article investigates feature selection in streaming data through incremental Markov boundary (MB) learning and proposes a novel algorithm. Different from existing algorithms focusing on prediction performance on off-line data, the MB is learned by analyzing conditional dependence/independence in data, which uncovers the underlying mechanism and is naturally more robust against the distribution shift. To learn MB in the data stream, the proposal transforms the learned information in previous data blocks to prior knowledge and employs them to assist MB discovery in current data blocks, where the likelihood of distribution shift and reliability of conditional independence test are monitored to avoid the negative impact from invalid prior information. Extensive experiments on synthetic and real-world datasets demonstrate the superiority of the proposed algorithm.

13.
Reprod Sci ; 30(4): 1281-1290, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36207578

RESUMO

Tideglusib is considered to be a promising alternative to nonyl alcohol-9 contraceptives. Previous studies have demonstrated that the rapid spermicidal effect of tideglusib at a high concentration (≥ 10 µM) may occur through detergent-like activity; however, the effect of low concentrations of tideglusib (< 5 µM) on sperm is unknown. We explored the intracellular mechanism of tideglusib (< 5 µM) on the immobilization of human sperm by exploring related signaling pathways in human sperm. After treatment with tideglusib (1.25 µM) for 2 h, sperm motility rate decreased to 0, while sperm membrane integrity rate was 70%. Protein tyrosine phosphorylation level and intracellular cyclic adenosine 3,5-monophosphate (cAMP) concentration decreased significantly compared to those in the control group. Isobutylmethylxanthine and 8-Bromo-cAMP relieved the inhibition of spermatozoa tyrosine phosphorylation, while tyrosine phosphorylation of sperm protein in the H89 and CALP1 treatment groups was significantly inhibited, and there was no difference in the tideglusib treatment group. H-89 and CALP1 reduced the level of serine phosphorylation of GSK-3α/ß (Ser21/9), while its level was enhanced by IBMX and 8-Bromo-cAMP. Our results show the existence of the GSK3-cAMP/PKA regulatory loop in human sperm, which may mediate the immobilization effect of tideglusib at low of concentrations (e.g., 1.25 µM) on sperm motility.


Assuntos
AMP Cíclico , Quinase 3 da Glicogênio Sintase , Humanos , Masculino , AMP Cíclico/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Quinase 3 da Glicogênio Sintase/farmacologia , 8-Bromo Monofosfato de Adenosina Cíclica/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Motilidade dos Espermatozoides/fisiologia , Sêmen/metabolismo , Espermatozoides/metabolismo , Fosforilação , Tirosina/metabolismo
14.
Talanta ; 260: 124627, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37182291

RESUMO

Due to the worldwide ecological and environmental issues induced by heavy metal pollution, including zinc and manganese, the ratio-metric discrimination of Zn2+ and Mn2+ based on CDs is urgently required. In this work, reduced CDs (re-CDs) with the intrinsic dual emissive peaks are obtained, and specific discrimination of Zn2+ and Mn2+ is realized by re-CDs with ratio-metric mode. With the addition of Zn2+, the fluorescent (FL) intensity at 650 nm increases obviously, while that at 680 nm progressively decreases. However, the presence of Mn2+ would induce the quenching of FL intensity at 680 nm while that at 650 nm remains constant. Then the Zn2+ and Mn2+ can be separately determined with the ratio of FL intensity at 650 nm to that at 680 mm (F650/F680). Under optimal conditions, the limit of detection (LOD) of Zn2+ is determined to be 9.09 nmol/L, and that for Mn2+ is estimated to be 0.93 nmol/L, which is much lower than previously reported work and standard level of Zn2+ and Mn2+ permitted in drinking water by WHO. Moreover, the specific recognition of Mn2+ and Zn2+ can be realized via the addition of different masking agents (ethylenediamine for Zn2+ and triethanolamine for Mn2+). Furthermore, our results reveal that the structural changes from -NH-CO to -NC-OH induced by Zn2+ contribute to the shift of FL peak from 680 to 650 nm while both static and dynamic quenching processes are involved in the detection of Mn2+. The ratio-metric probe was successfully applied to Zn2+ and Mn2+ determination in human serum samples and Sandy Lake water.

15.
Int J Biol Macromol ; 238: 124088, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-36948332

RESUMO

Polydopamine nanoparticles (PDA NPs) are commonly used for photothermal therapy (PTT) of cancer because of their good biocompatibility and photothermal conversion capability. However, it is difficult to achieve a good tumor inhibition effect with a single PTT of PDA. Therefore, in this work, we prepared a combined anticancer nanosystem for enhanced chemodynamic therapy (CDT)/PTT by coating PDAs with an (-)-epigallocatechin gallate (EGCG)/iron (Fe) metal-polyphenol network (MPN). The MPN shell of this nanosystem named EGCG@PDA is degraded by the weakly acidic environment intracellular, releasing EGCG and Fe3+. EGCG inhibits the expression of heat shock proteins (HSPs) in cancer cells, thus eliminating their thermal protection against cancer cells for enhanced PTT. Meanwhile, the reductive EGCG can also reduce Fe3+ to Fe2+, to catalyze the decomposition of overexpressed hydrogen peroxide (H2O2) in cancer cells to generate strong oxidative hydroxyl radicals (OH), i.e., catalyzing the Fenton reaction, for CDT. After the Fenton reaction, the re-oxidized Fe ions can be reduced again by EGCG and reused to catalyze the Fenton reaction, which can achieve enhanced CDT. Both in vitro and in vivo studies have shown that EGCG@PDA has low dark toxicity and good anticancer effects. It is expected to be used for precision cancer therapy.


Assuntos
Nanopartículas , Neoplasias , Humanos , Polifenóis , Fototerapia , Peróxido de Hidrogênio , Neoplasias/tratamento farmacológico , Metais , Linhagem Celular Tumoral
16.
Acta Biomater ; 159: 312-323, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36708854

RESUMO

As a controllable, simple method with few side effects, near-infrared (NIR) light-based photothermal therapy (PTT) has been proven an effective cancer therapeutic approach. However, PTT-induced inflammation is a potential negative factor. And the overexpressed heat shock proteins (HSPs) by cancer cells can protect them from hyperthermia during PTT. In this work, small-size Ti3C2Tx MXene nanosheets with high photothermal conversion efficiency in the region of NIR, high cargo loading capability and good free radical scavenging capability were chosen for cancer PTT and anti-inflammation. And (-)-epigallocatechin gallate (EGCG) was applied to form EGCG/Fe metal-polyphenol nanodots on the nanosheets. EGCG being released in acid cancer cells could reduce the expression of HSPs and could be used for anti-inflammation. As a result, the complex nanosheets named MXene@EGCG could achieve enhanced cancer PTT and be anti-inflammatory. Both in vitro and in vivo studies proved the good photothermal ability of MXene@EGCG and demonstrated that it could inhibit the expression of HSPs in tumor cells and relieve PTT-induced inflammation. Therefore, the nanosheets show good results in tumor ablation with a low level of inflammation, which provides another possibility for cancer therapy. STATEMENT OF SIGNIFICANCE: Photothermal therapy (PTT)-induced inflammation plays an essential role in some important stages of tumor development and is unfavorable for cancer treatment. And hyperthermia leads to the overexpression of heat shock proteins (HSPs) in cancer cells, which limits the therapeutic effect of PTT. Therefore, we coated small-size Ti3C2Tx MXene nanosheets with (-)-epigallocatechin gallate (EGCG)/Fe metal-polyphenol nanodots and named them as MXene@EGCG. This system shows a good photothermal conversion efficiency at 808 nm. And it can release EGCG in cancer cells to inhibit the expression of HSPs, thus achieving an enhanced cancer PTT. Both MXene and EGCG can also diminish the PTT-trigged inflammation. Both in vitro and in vivo studies prove the good anti-cancer PTT effect and anti-inflammation capability of MXene@EGCG.


Assuntos
Hipertermia Induzida , Neoplasias , Humanos , Fototerapia/métodos , Terapia Fototérmica , Hipertermia Induzida/métodos , Titânio , Neoplasias/patologia , Anti-Inflamatórios , Proteínas de Choque Térmico , Linhagem Celular Tumoral
17.
Front Genet ; 14: 1065033, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36936414

RESUMO

Background: To reveal candidate genes and the molecular genetic mechanism underlying primary feather color trait in ducks, a genome-wide association study (GWAS) for the primary feather color trait was performed based on the genotyping-by-sequencing (GBS) technology for a native Chinese female duck, Longyan Shan-ma ducks. Methods: Blood genomic DNA from 314 female Longyan Shan-ma duck were genotyped using GBS technology. A GWAS for the primary feather color trait with genome variations was performed using an univariate linear mixed model based on all SNPs in autosomes. Results: Seven genome-wide significant single nucleotide polymorphisms (SNPs, Bonferroni-adjusted p-value <8.03 × 10-7) within the introns of the genes STARD9, ZNF106, SLC7A5, and BANP genes were associated with the primary feather color trait. Twenty-two genome-wide suggestive SNPs (Bonferroni-adjusted p-value <1.61 × 10-5) of 17 genes (besides ZNF106 and SLC7A5) were also identified. Seven SNPs were located at one 0.22 Mb region (38.65-38.87 Mb) on chromosome 5, and six SNPs were located at one 0.31 Mb region (19.53-19.84 Mb) on chromosome 11. The functions of STARD9, SLC7A5, BANP, LOC101798015, and IPMK were involved pigmentation and follicle development, especially, STARD9 upregulated expression in black feather (haplotype-CCCC) bulb tissue compared with in pockmarked feather (haplotype-TGTT) bulb tissue, implicating these genes as candidate genes for primary feather color trait. Conclusion: The preliminarily findings suggested candidate genes and regions, and the genetic basis of primary feather color trait in a female duck.

18.
J Mol Cell Cardiol ; 52(3): 753-60, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22227328

RESUMO

Elevated plasma homocysteine (Hcy) is a risk factor for cardiovascular disease. While Hcy has been shown to promote endothelial dysfunction by decreasing the bioavailability of nitric oxide and increasing oxidative stress in the vasculature, the effects of Hcy on cardiomyocytes remain less understood. In this study we explored the effects of hyperhomocysteinemia (HHcy) on myocardial function ex vivo and examined the direct effects of Hcy on cardiomyocyte function and survival in vitro. Studies with isolated hearts from wild type and HHcy mice (heterozygous cystathionine-beta synthase deficient mice) demonstrated that HHcy mouse hearts had more severely impaired cardiac relaxation and contractile function and increased cell death following ischemia reperfusion (I/R). In isolated cultured adult rat ventricular myocytes, exposure to Hcy for 24 h impaired cardiomyocyte contractility in a concentration-dependent manner, and promoted apoptosis as revealed by terminal dUTP nick-end labeling and cleaved caspase-3 immunoblotting. These effects were associated with activation of p38 MAPK, decreased expression of thioredoxin (TRX) protein, and increased production of reactive oxygen species (ROS). Inhibition of p38 MAPK by the selective inhibitor SB203580 (5 µM) prevented all of these Hcy-induced changes. Furthermore, adenovirus-mediated overexpression of TRX in cardiomyocytes significantly attenuated Hcy-induced ROS generation, apoptosis, and impairment of myocyte contractility. Thus, Hcy may increase the risk for CVD not only by causing endothelial dysfunction, but also by directly exerting detrimental effects on cardiomyocytes.


Assuntos
Apoptose/efeitos dos fármacos , Homocisteína/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Estresse Oxidativo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Células Cultivadas , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Homocisteína/sangue , Hiper-Homocisteinemia/metabolismo , Hiper-Homocisteinemia/fisiopatologia , Técnicas In Vitro , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Contração Miocárdica/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
19.
J Hazard Mater ; 435: 128976, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35472541

RESUMO

Since the excess exposure to F- may induce serious issues to human health, the effective adsorption and sensitive detection of F- is essential. Therefore, carbon dots (CDs) capped CeO2 (CeO2@CDs) was synthesized via hydrothermal treatment of tannic acid and CeCl3. Due to abundant phenolic hydroxyl are reserved and excellent hydrophilicity, CeO2@CDs possess high F- adsorption capacity. The partition coefficient parameters (PC) are determined to be 2.65 L/g, which is comparable with previous work. The kinetics results and adsorption isotherm are consistent with pseudo-second-order model and Freundlich model, respectively, indicating the chemisorption dominate the adsorption, mainly via the ion exchange between hydroxyl and F-. Since phenolic hydroxyl existed on the CeO2@CDs, synergetic effect of CDs and CeO2 contribute to superior ROS eliminating capacity, even at acidic conditions. Moreover, due to the ROS scavenging of CeO2 @CDs abilities can be potentiated by F-, colorimetric detection of F- can be realized via horseradish peroxidase as an indicator. The linear range is 0.3-2.1 mM with limit of detection is 0.13 mg/L. The current results imply that CeO2@CDs possess potential in both efficient removal and sensitive detection of F- related contamination issues and elucidation of development to address other anions related issues.


Assuntos
Cério , Nanopartículas , Carbono , Fluoretos , Humanos , Espécies Reativas de Oxigênio
20.
Artigo em Inglês | MEDLINE | ID: mdl-35939477

RESUMO

As data sources become ever more numerous with increased feature dimensionality, feature selection for multiview data has become an important technique in machine learning. Semi-supervised multiview feature selection (SMFS) focuses on the problem of how to obtain a discriminative feature subset from heterogeneous feature spaces in the case of abundant unlabeled data with little labeled data. Most existing methods suffer from unreliable similarity graph structure across different views since they separate the graph construction from feature selection and use the fixed graphs that are susceptible to noisy features. Furthermore, they directly concatenate multiple feature projections for feature selection, neglecting the contribution diversity among projections. To alleviate these problems, we present an SMFS to simultaneously select informative features and learn a unified graph through the data fusion from aspects of feature projection and similarity graph. Specifically, SMFS adaptively weights different feature projections and flexibly fuses them to form a joint weighted projection, preserving the complementarity and consensus of the original views. Moreover, an implicit graph fusion is devised to dynamically learn a compatible graph across views according to the similarity structure in the learned projection subspace, where the undesirable effects of noisy features are largely alleviated. A convergent method is derived to iteratively optimize SMFS. Experiments on various datasets validate the effectiveness and superiority of SMFS over state-of-the-art methods.

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