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1.
Nature ; 617(7962): 818-826, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37198486

RESUMO

Cancer cells rewire metabolism to favour the generation of specialized metabolites that support tumour growth and reshape the tumour microenvironment1,2. Lysine functions as a biosynthetic molecule, energy source and antioxidant3-5, but little is known about its pathological role in cancer. Here we show that glioblastoma stem cells (GSCs) reprogram lysine catabolism through the upregulation of lysine transporter SLC7A2 and crotonyl-coenzyme A (crotonyl-CoA)-producing enzyme glutaryl-CoA dehydrogenase (GCDH) with downregulation of the crotonyl-CoA hydratase enoyl-CoA hydratase short chain 1 (ECHS1), leading to accumulation of intracellular crotonyl-CoA and histone H4 lysine crotonylation. A reduction in histone lysine crotonylation by either genetic manipulation or lysine restriction impaired tumour growth. In the nucleus, GCDH interacts with the crotonyltransferase CBP to promote histone lysine crotonylation. Loss of histone lysine crotonylation promotes immunogenic cytosolic double-stranded RNA (dsRNA) and dsDNA generation through enhanced H3K27ac, which stimulates the RNA sensor MDA5 and DNA sensor cyclic GMP-AMP synthase (cGAS) to boost type I interferon signalling, leading to compromised GSC tumorigenic potential and elevated CD8+ T cell infiltration. A lysine-restricted diet synergized with MYC inhibition or anti-PD-1 therapy to slow tumour growth. Collectively, GSCs co-opt lysine uptake and degradation to shunt the production of crotonyl-CoA, remodelling the chromatin landscape to evade interferon-induced intrinsic effects on GSC maintenance and extrinsic effects on immune response.


Assuntos
Histonas , Lisina , Neoplasias , Processamento de Proteína Pós-Traducional , Cromatina/química , Cromatina/genética , Cromatina/metabolismo , Glutaril-CoA Desidrogenase/metabolismo , Histonas/química , Histonas/metabolismo , Lisina/deficiência , Lisina/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , RNA de Cadeia Dupla/imunologia , Humanos , Animais , Camundongos , Interferon Tipo I/imunologia
2.
Cell ; 148(5): 1039-50, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22385967

RESUMO

Impairment of working memory is one of the most important deleterious effects of marijuana intoxication in humans, but its underlying mechanisms are presently unknown. Here, we demonstrate that the impairment of spatial working memory (SWM) and in vivo long-term depression (LTD) of synaptic strength at hippocampal CA3-CA1 synapses, induced by an acute exposure of exogenous cannabinoids, is fully abolished in conditional mutant mice lacking type-1 cannabinoid receptors (CB(1)R) in brain astroglial cells but is conserved in mice lacking CB(1)R in glutamatergic or GABAergic neurons. Blockade of neuronal glutamate N-methyl-D-aspartate receptors (NMDAR) and of synaptic trafficking of glutamate α-amino-3-hydroxy-5-methyl-isoxazole propionic acid receptors (AMPAR) also abolishes cannabinoid effects on SWM and LTD induction and expression. We conclude that the impairment of working memory by marijuana and cannabinoids is due to the activation of astroglial CB(1)R and is associated with astroglia-dependent hippocampal LTD in vivo.


Assuntos
Astrócitos/metabolismo , Canabinoides/farmacologia , Hipocampo/metabolismo , Memória de Curto Prazo/efeitos dos fármacos , Receptor CB1 de Canabinoide/metabolismo , Animais , Cannabis/química , Hipocampo/citologia , Depressão Sináptica de Longo Prazo/efeitos dos fármacos , Camundongos , Plasticidade Neuronal , Ratos , Receptor CB1 de Canabinoide/genética
3.
Cell Mol Life Sci ; 80(3): 73, 2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36842139

RESUMO

Barrier-to-autointegration factor (BAF/BANF) is a nuclear lamina protein essential for nuclear integrity, chromatin structure, and genome stability. Whereas complete loss of BAF causes lethality in multiple organisms, the A12T missense mutation of the BANF1 gene in humans causes a premature aging syndrome, called Néstor-Guillermo Progeria Syndrome (NGPS). Here, we report the first in vivo animal investigation of progeroid BAF, using CRISPR editing to introduce the NGPS mutation into the endogenous Drosophila baf gene. Progeroid BAF adults are born at expected frequencies, demonstrating that this BAF variant retains some function. However, tissue homeostasis is affected, supported by studies of the ovary, a tissue that depends upon BAF for stem cell survival and continuous oocyte production. We find that progeroid BAF causes defects in germline stem cell mitosis that delay anaphase progression and compromise chromosome segregation. We link these defects to decreased recruitment of centromeric proteins of the kinetochore, indicating dysfunction of cenBAF, a localized pool of dephosphorylated BAF produced by Protein Phosphatase PP4. We show that DNA damage increases in progenitor germ cells, which causes germ cell death due to activation of the DNA damage transducer kinase Chk2. Mitotic defects appear widespread, as aberrant chromosome segregation and increased apoptosis occur in another tissue. Together, these data highlight the importance of BAF in establishing centromeric structures critical for mitosis. Further, these studies link defects in cenBAF function to activation of a checkpoint that depletes progenitor reserves critical for tissue homeostasis, aligning with phenotypes of NGPS patients.


Assuntos
Drosophila , Progéria , Animais , Feminino , Humanos , Drosophila/metabolismo , Progéria/genética , Progéria/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas Nucleares/metabolismo , Centrômero/metabolismo , Homeostase/genética
4.
Development ; 147(9)2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32345742

RESUMO

The nuclear lamina (NL) is an extensive protein network that underlies the inner nuclear envelope. This network includes LAP2-emerin-MAN1 domain (LEM-D) proteins that associate with the chromatin and DNA-binding protein Barrier-to-autointegration factor (BAF). Here, we investigate the partnership between three NL Drosophila LEM-D proteins and BAF. In most tissues, only Emerin/Otefin is required for NL enrichment of BAF, revealing an unexpected dependence on a single LEM-D protein. Prompted by these observations, we studied BAF contributions in the ovary, a tissue where Emerin/Otefin function is essential. We show that germ cell-specific BAF knockdown causes phenotypes that mirror emerin/otefin mutants. Loss of BAF disrupts NL structure, blocks differentiation and promotes germ cell loss, phenotypes that are partially rescued by inactivation of the ATR and Chk2 kinases. These data suggest that, similar to emerin/otefin mutants, BAF depletion activates the NL checkpoint that causes germ cell loss. Taken together, our findings provide evidence for a prominent NL partnership between the LEM-D protein Emerin/Otefin and BAF, revealing that BAF functions with this partner in the maintenance of an adult stem cell population.


Assuntos
Quinase do Ponto de Checagem 2/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Células Germinativas/citologia , Células Germinativas/metabolismo , Proteínas Nucleares/metabolismo , Animais , Proteínas de Ligação a DNA/genética , Drosophila , Proteínas de Drosophila/genética , Feminino , Masculino , Lâmina Nuclear/metabolismo , Proteínas Nucleares/genética , Oogênese/genética , Oogênese/fisiologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-37883762

RESUMO

Cerebral infarction is characterized by a high morbidity, disability, and fatality rate. This study explored the relationship between serum ß2 microglobulin (ß2-MG), HGF, lipoprotein-associated phospholipase A2 (Lp-PLA2) and carotid atherosclerosis in patients with hypertension combined with cerebral infarction and their prognostic value. A total of 320 patients with cerebral infarction complicated with hypertension who were hospitalized from January 2015 to January 2020 were collected. HGF, Lp-PLA2 and ß2-MG levels were detected. Plaque score (Crouse score) was the patient's cumulative plaque thickness measurements. Additionally, the maximum plaque thickness and the number of plaques were measured.. The correlation was found between high ß2-MG levels and the poor prognosis (HR: 1.29, 95% CI: 1.03-1.52, P = .022). Patients who had elevated levels of HGF were also less likely to have a positive outcome (HR: 1.38, 95% CI: 1.26-1.56, P = .015). High Lp-PLA2 levels were associated with a worse prognosis than low levels (HR: 1.74, 95% CI: 1.29-2.32, P = .015). In conclusion, the levels of ß2-MG, HGF, and Lp-PLA2 in patients with hypertension combined with cerebral infarction were substantially linked with carotid plaques.

6.
J Environ Manage ; 328: 116888, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36516713

RESUMO

Data scarcity caused by extreme conditions during storms adds difficulties in performing pollution source apportionment. This study integrated nonnegative matrix factorization with the imputation method (NMF-IM) to fill in missing data (NAs) and conduct source apportionment. A total of 367 river samples and 35 runoff samples were taken from the Banqiao and Nanfei River basins located in Hefei, China, during four rainfall events from June to August 2020. Sixteen indicators were quantified and used for source diagnostics using NMF-IM. The results showed that total phosphorus (TP) had higher concentrations and more violent fluctuations than total nitrogen (TN) in river samples taken from rain. NMF-IM was shown to recover the value distribution of NAs approximately. The source profiles and contribution rates calculated by NMF-IM with NAs were close to the original results calculated by NMF without NAs, with root mean square error of less than 2.3% and differences less than 9.5%. Multiple forms of nitrogen and phosphorus indicators benefit reaching reasonable source diagnostics results. At least four indicators were needed to reach the same contribution rates as 16 indicator diagnostics. The two good indicator combination groups are nitrate (NO3-N), nitrite (NO2-N), ammonia nitrogen (NH3-N), and total suspended solids (TSS) and NO3-N, NO2-N, phosphorus (PO4-P), and TSS. The pollution source contributions changed with the Antecedent dry period (ADPs) of rain events. Treated tailwater and untreated sewage were major sources, contributing more than 80% of the total pollution of the rainstorm events with short ADPs. Dust wash became the dominant contributor after 60 min and contributed 36% of the total pollution of rainstorm events with long ADPs. The average source contribution rates for rainfall events in the Banqiao River were treated tailwater (41%) > untreated sewage (27%) > dust wash (19%) > other sources (16%). The pollution source diagnostics results were verified to be reasonable by simulation using tested run-off data and literature results.


Assuntos
Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Esgotos , Dióxido de Nitrogênio , Nitrogênio/análise , Fósforo/análise , Rios , China
7.
J Sci Food Agric ; 103(13): 6280-6287, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37177869

RESUMO

BACKGROUND: Grapes are highly vulnerable to infection by carbon black aspergilli, which produce ochratoxin A (OTA), a mycotoxin. Carbendazim and hymexazol are widely applied to control grape diseases. Howerver, fungicides, toxigenic fungi, and OTA can be transferred from grapes to wine causing potential safety issues. The impact of these residues on fungal populations and OTA during vinification are currently unclear. Here we investigated the effects of carbendazim and hymexazol on the viability of Aspergillus carbonarius and OTA contamination during an indoor wine-processing experiment. RESULTS: The population size of A. carbonarius substantially increased at 24 h followed by a significantly decreased at 72 h after destemming and crushing. However, carbendazim and hymexazol notably inhibited the growth of A. carbonarius in must samples. In addition, yeast growth was substantially deleyed by carbendazim, hymexazol, and OTA during the first 3 days in compared with the control. Carbendazim, hymexazol, and OTA residues declined over time, and the processing factors (PFs) for carbendazim and hymexazol throughout vinification were 0.164, 0.074, and 0.185-0.476, respectively. Carbendazim and hymexazol each reduced OTA concentrations. However, there was no significant difference after 48 h. Addition of carbendazim or hymexazol significantly reduced the level of A. carbonarius but had no significant effect on the final concentration of OTA in mature wine. CONCLUSION: The wine-making process can reduce the residues of OTA, carbendazim, and hymexazol in grapes, but it is recommended that grapes chosen to make wine should be free of A. carbonarius contamination. © 2023 Society of Chemical Industry.


Assuntos
Vitis , Vinho , Vinho/análise , Saccharomyces cerevisiae , Vitis/química
8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(5): 863-873, 2023 Sep.
Artigo em Zh | MEDLINE | ID: mdl-37866940

RESUMO

Objective: Based on single-cell RNA sequencing (scRNA-seq) to explore immune characteristics in the peripheral blood of patients with Alzheimer's disease (AD) as biomarkers. Methods: GSE168522, the scRNA-seq dataset of AD peripheral blood immune cells, was downloaded from the Gene Expression Omnibus (GEO) database and was analyzed in the RAD-Blood web server (http://www.bioinform.cn/RAD-Blood/). The changes in blood cell composition in AD patients were analyzed. The abnormal communications between different types of cells in AD patients were investigated by the CellChat R package. Results: There were two kinds of CD8 + T cells in the blood of AD patients and healthy individuals, one of which highly expressed granzyme K ( GZMK) (false discovery rate [FDR]<0.05), and the other highly expressed GZMA, GZMB, and GZMH (FDR<0.05). In the blood of AD patients, the content of GZMK + CD8 + T cells was increased by 32.9% ( P=5.15E-21), their interactions with other cell types were increased, and they might be associated with AD through the abnormal signal transduction of major histocompatibility complex class Ⅰ (MHC-Ⅰ). Erythrocyte provided the main ligands, that are, human leukocyte antigen (HLA) class Ⅰ molecules, including HLA- A, HLA- B, HLA- C, and HLA- E, for the abnormal MHC-Ⅰ signaling pathway of GZMK + CD8 + T cells. The RESISTIN signaling pathway was specifically enriched in the blood of AD patients. Conclusion: The increased content of peripheral blood GZMK + CD8 + T cells, the increased interaction between GZMK + CD8 + T cells and erythrocytes, and the enhanced RESISTIN pathway are potential blood biomarkers of AD.


Assuntos
Doença de Alzheimer , Resistina , Humanos , Granzimas , Transcriptoma , Doença de Alzheimer/genética , Linfócitos T CD8-Positivos , Biomarcadores
9.
Opt Express ; 30(26): 47038-47047, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36558641

RESUMO

In this paper, high spatial-resolution distributed temperature sensing has been realized based on a femtosecond laser written ultra-weak Fabry-Perot Array (FPA). 50 identical Fabry-Perot cavities are fabricated in a 10 mm long optical fiber by femtosecond laser point-by-point written technology, and the corresponding spatial resolution is as high as 200 µm. Besides, by employing the total phase demodulation method, the optical path lengths (OPLs) in the ultra-weak FPA are successively demodulated based on the Rayleigh backscattering signal recorded by an optical frequency domain reflectometry (OFDR), and therefore the absolute temperature values instead of the relative ones can be obtained. When compared with the conventional single mode fiber-based OFDR, the proposed ultra-weak FPA presents both higher spatial resolution and lower temperature sensing uncertainty (0.25 °C) benefiting from the periodically enhanced Rayleigh backscattering. Furthermore, the experiments also confirm that the ultra-weak FPA can be applied for absolute temperature field profile sensing with large temperature gradient, which is particularly suitable for high-resolution temperature measurement of miniature devices.

10.
Acta Biochim Biophys Sin (Shanghai) ; 54(3): 370-377, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35538036

RESUMO

Oxidative stress and endoplasmic reticulum (ER) stress play crucial roles in pancreatic ß cell destruction, leading to the development and progression of type 1 diabetes mellitus (T1DM). Curcumin, extracted from plant turmeric, possesses multiple bioactivities such as antioxidant, anti-inflammatory and anti-apoptosis properties and . However, it remains unknown whether curcumin improves ER stress to prevent ß cells from apoptosis. In this study, we aim to investigate the role and mechanism of curcumin in ameliorating HO-induced injury in MIN6 (a mouse insulinoma cell line) cells. Cell viability is examined by CCK8 assay. Hoechst 33258 staining, TUNEL and flow cytometric assay are performed to detect cell apoptosis. The relative amounts of reactive oxygen species (ROS) are measured by DCFH-DA. WST-8 is used to determine the total superoxide dismutase (SOD) activity. Protein expressions are determined by western blot analysis and immunofluorescence staining. Pretreatment with curcumin prevents MIN6 cells from HO-induced cell apoptosis. Curcumin decreases ROS generation and inhibits protein kinase like ER kinase (PERK)-C/EBP homologous protein (CHOP) signaling axis, one of the critical branches of ER stress pathway. Moreover, incubation with curcumin activates silent information regulator 1 (SIRT1) expression and subsequently decreases the expression of CHOP. Additionally, EX527, a specific inhibitor of SIRT1, blocks the protective effect of curcumin on MIN6 cells exposed to HO. In sum, curcumin inhibits the PERK-CHOP pathway of ER stress mediated by SIRT1 and thus ameliorates HO-induced MIN6 cell apoptosis, suggesting that curcumin and SIRT1 may provide a potential therapeutic approach for T1DM.


Assuntos
Curcumina , Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Animais , Apoptose , Curcumina/farmacologia , Curcumina/uso terapêutico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Estresse do Retículo Endoplasmático , Células Secretoras de Insulina/metabolismo , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 1/metabolismo , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo
11.
World J Surg Oncol ; 20(1): 164, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35606755

RESUMO

BACKGROUND: Rapid advances in transcriptomic profiles have resulted in recognizing IRLs (immune-related long noncoding RNAs), as modulators of the expression of genes related to immune cells that mediate immune inhibition as well as immune stimulatory, indicating LncRNAs play fundamental roles in immune modulation. Hence, we establish an IRL classifier to precisely predict prognosis and immunotherapeutic efficiency in laryngeal squamous cell carcinoma (LSCC). METHODS: LSCC RNA-seq (RNA sequencing) datasets, somatic mutation data, and corresponding clinicopathologic information were acquired from TCGA (the Cancer Genome Atlas) and Gene Expression Omnibus (GEO) databases. Spearman correlation analysis identified LncRNAs associated with immune-related genes (IRG). Based on Lasso penalized regression and random forest (RF), we constructed an IRL classifier associated with prognosis. GEO database was utilized to validate the IRL classifier. The predictive precision and clinical application of the IRL classifier were assessed and compared to clinicopathologic features. The immune cell infiltration of LSCC was calculated via CIBERSORTx tools and ssGSEA (single-sample gene set enrichment analysis). Then, we systematically correlated the IRL classifier with immunological characteristics from multiple perspectives, such as immune-related cells infiltrating, tumor microenvironment (TME) scoring, microsatellite instability (MSI), tumor mutation burden (TMB), and chemokines. Finally, the TIDE (tumor immune dysfunction and exclusion) algorithm was used to predict response to immunotherapy. RESULTS: Based on machine learning approach, three prognosis-related IRLs (BARX1-DT, KLHL7-DT, and LINC02154) were selected to build an IRL classifier. The IRL classifier could availably classify patients into the low-risk and high-risk groups based on the different endpoints, including recurrence-free survival (RFS) and overall survival (OS). In terms of predictive ability and clinical utility, the IRL classifier was superior to other clinical characteristics. Encouragingly, similar results were observed in the GEO databases. Immune infiltration analysis displayed immune cells that are significantly richer in low-risk group, CD8 T cells and activated NK cells via CIBERSORTx algorithm as well as activated CD8 T cell via ssGSEA. Additionally, compared with the high-risk group, immune score, CD8 T effector was higher in the low-risk group, yet stromal score, score of p53 signaling pathway and TGFher in the Tx algorithm, was lower in the low-risk group. Corresponding results were confirmed in GEO dataset. Finally, TIDE analysis uncovered that the IRL classifier may be effectually predict the clinical response of immunotherapy in LSCC. CONCLUSION: Based on BARX1-DT, KLHL7-DT, and LINC02154, the IRL classifier was established, which can be used to predict the prognosis, immune infiltration status, and immunotherapy response in LSCC patients and might facilitate personalized counseling for immunotherapy.


Assuntos
Neoplasias de Cabeça e Pescoço , RNA Longo não Codificante , Biomarcadores Tumorais/genética , Humanos , Imunoterapia , Prognóstico , RNA Longo não Codificante/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Microambiente Tumoral
12.
J Sci Food Agric ; 102(4): 1415-1421, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34375005

RESUMO

BACKGROUND: Carbendazim and epoxiconazole are widely applied to control anthracnose and sand bark fungal diseases in citrus. The residues of these two fungicides in citrus and their potential risk to consumers have generated much public concern. We therefore sought to investigate the dissipation, residue, and dietary risk assessment of carbendazim and epoxiconazole in citrus. RESULTS: The dissipation kinetics and residue levels of carbendazim and epoxiconazole in citrus under field conditions were measured using dispersive solid-phase extraction and ultra-high-performance liquid chromatography-tandem mass spectrometry. The citrus samples were extracted with acetonitrile and purified by primary secondary amine sorbent. The mean recoveries of carbendazim and epoxiconazole ranged from 86.2 to 105.6% and relative standard deviations were ≤9.8%. The half-lives of carbendazim and epoxiconazole in whole citrus ranged from 2.0 to 18.0 days. Hazard quotient (HQ) and risk quotient (RQ) models were applied to whole citrus for dietary exposure risk assessment based on the terminal residue test. Hazard quotients ranged from 0.066 to 0.134% and RQs from 18.48 to 82.12%. CONCLUSION: Carbendazim and epoxiconazole in citrus degraded rapidly following first-order kinetics models. The dietary risk of exposure to both carbendazim and epoxiconazole through citrus, based on HQ and RQ, was acceptable for human consumption. This study indicates scientifically validated maximum residue limits in citrus, which are currently lacking for epoxiconazole in China. © 2021 Society of Chemical Industry.


Assuntos
Citrus , Resíduos de Praguicidas , Benzimidazóis , Carbamatos , China , Compostos de Epóxi , Humanos , Resíduos de Praguicidas/análise , Medição de Risco , Espectrometria de Massas em Tandem , Triazóis
13.
Bioorg Chem ; 116: 105299, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34454300

RESUMO

The development of cationic polymers as non-viral gene vectors has been hurdled by their high toxicity, thus degradable and biocompatible polymers are urgently demanded. Herein, five polyesters (B3a-B3e) were synthesized based on the ring-opening copolymerization between α-allyl-δ-valerolactone and δ-valerolactone derivatives decorated with alkyl or alkoxyl chains of different lengths, followed by the modification with 1,5,9-triazacyclododecyl ([12]aneN3) through thiol-ene click reactions. The five polyesters effectively condensed DNA into nanoparticles. Of them, B3a with a shorter alkyl chain and B3d with more positive charged units showed stronger DNA condensing performance and can completely retard the migration of DNA at N/P = 1.6 in the presence of DOPE. B3b/DOPE with a longer alkyl chain exhibited the highest transfection efficiency in HeLa cells with 1.8 times of 25 kDa PEI, while B3d/DOPE with more positive charged units exhibited highest transfection efficiency in A549 cells with 2.3 times of 25 kDa PEI. B3b/DOPE and B3d/DOPE successfully delivered pEGFP into zebrafish, which was superior to 25 kDa PEI (1.5 folds and 1.1 folds, respectively). The cytotoxicity measurements proved that the biocompatibility of these polyesters was better than 25 kDa PEI, due to their degradable property in acid environment. The results indicated that these cationic polyesters can be developed as potential non-viral gene vectors for DNA delivery.


Assuntos
DNA/genética , Técnicas de Transferência de Genes , Lactonas/química , Nanopartículas/química , Poliésteres/química , Cátions/química , Cátions/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Vetores Genéticos/química , Humanos , Estrutura Molecular , Plasmídeos/genética , Poliésteres/farmacologia , Polimerização , Relação Estrutura-Atividade
14.
Acta Biochim Biophys Sin (Shanghai) ; 53(1): 46-53, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33242093

RESUMO

Endoplasmic reticulum (ER) stress plays a critical role in pancreatic ß cell destruction which leads to the pathogenesis of type 1 diabetes mellitus (T1DM). Vitamin D (VD) has been reported to reduce the risk of T1DM; however, it remains unknown whether VD affects ER stress in pancreatic ß cells. In this study, we investigated the role of the active form of VD, 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3], in ER stress-induced ß cell apoptosis and explored its potential mechanism in mouse insulinoma cell line mouse insulinoma 6 (MIN6). The results of cell counting kit-8 (CCK8) and flow cytometric analyses showed that 1,25-(OH)2D3 caused a significant increase in the viability of MIN6 cells injured by H2O2. The protein kinase like ER kinase (PERK) signal pathway, one of the most conserved branches of ER stress, was found to be involved in this process. H2O2 activated the phosphorylation of PERK, upregulated the activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP) expression, and subsequently initiated cell apoptosis, which were significantly reversed by 1,25-(OH)2D3 pretreatment. In addition, GSK2606414, a specific inhibitor of PERK, suppressed PERK phosphorylation and reduced the expressions of ATF4 and CHOP, leading to a significant decrease in ß cell apoptosis induced by H2O2. Taken together, the present findings firstly demonstrated that 1,25-(OH)2D3 could prevent MIN6 cells against ER stress-associated apoptosis by inhibiting the PERK-ATF4-CHOP pathway. Therefore, our results suggested that 1,25-(OH)2D3 might serve as a potential therapeutic target for preventing pancreatic ß cell destruction in T1DM.


Assuntos
Fator 4 Ativador da Transcrição/antagonistas & inibidores , Calcitriol/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição CHOP/antagonistas & inibidores , eIF-2 Quinase/antagonistas & inibidores , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Indóis/farmacologia , Células Secretoras de Insulina/citologia , Camundongos
15.
J Environ Manage ; 298: 113514, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34391108

RESUMO

The effect of rainfall on the water quality of urban lakes is related to the surrounding land use types. Six lakes surrounded by business units (commercial lakes) and park green spaces (park lakes) in the central area of Beijing, China, were monitored between June 2013 and October 2015. A total of 638 water samples were obtained. The results showed that the water quality was generally worse in the rainy season than in the dry season, with the mean dissolved oxygen (DO) concentration declining by 25.1 %. Compared to the rise in DO of park lakes after rainfall, commercial lakes showed a decreased DO. The nitrate nitrogen (NO3--N) concentration decreased after rain, and that in commercial lakes decreased more than that in park lakes. Different from DO and NO3--N, the ammonia nitrogen (NH4+-N)), total suspended solids (TSS) and total phosphorus (TP) concentrations of the lakes increased obviously after rain. The values in park lakes increased 138 % (NH4+-N)), 120 % (TSS) and 69 % (TP) more than those in commercial lakes. Principal component analysis (PCA) results illustrated that green space was the main source of TSS and TP for urban lakes. Most of the nitrogen (N) comes from artificial impervious surfaces. These results will help target pollutant control for urban lakes.


Assuntos
Poluentes Químicos da Água , Qualidade da Água , China , Monitoramento Ambiental , Lagos , Nitrogênio/análise , Fósforo/análise , Chuva , Movimentos da Água , Poluentes Químicos da Água/análise
16.
J Environ Sci Health B ; 56(6): 540-547, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33979275

RESUMO

A rapid and sensitive method for the identification and quantification of quintrione residue in brown rice, rice husk, and rice straw matrices was developed and validated. Samples were extracted with acetonitrile, purified with octadecylsilane (C18) and graphitized carbon black (GCB) sorbents, and quantified using ultrahigh-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). The developed method exhibited excellent linearity (R2 ≥ 0.9988), and the limit of quantitation was 2 µg/kg in all matrices. The method also had outstanding trueness and recoveries (90.5-111.1%) at four spiked levels (2, 20, 200, and 2000 µg/kg) with intraday and interday precisions of 0.7-6.5% and 5.2-11.8%, respectively, in the three matrices. The applicability of the method was tested by determining the dissipation rate of quintrione in rice straw under field conditions, and the measured data fit the Hockey stick kinetic model with R2 values of 0.9349-0.9983. The half-lives of quintrione in rice straw ranged from 2.7 to 16.5 days. The results indicate that the method is effective and reliable for the detection of quintrione residue in rice paddy fields, and the dissipation data provide guidance for the safe application of quintrione.


Assuntos
Herbicidas/análise , Oryza/química , Resíduos de Praguicidas/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem
17.
Artigo em Inglês | MEDLINE | ID: mdl-28702704

RESUMO

Ezrin is a critical structural protein that organizes receptor complexes and orchestrates their signal transduction. In this study, we review the ezrin-meditated regulation of critical receptor complexes, including the epidermal growth factor receptor (EGFR), CD44, vascular cell adhesion molecule (VCAM), and the deleted in colorectal cancer (DCC) receptor. We also analyze the ezrin-meditated regulation of critical pathways associated with asthma, such as the RhoA, Rho-associated protein kinase (ROCK), and protein kinase A (cAMP/PKA) pathways. Mounting evidence suggests that ezrin plays a role in controlling airway cell function and potentially contributes to respiratory diseases. Ezrin can participate in asthma pathogenesis by affecting bronchial epithelium repair, T lymphocyte regulation, and the contraction of the airway smooth muscle cells. These studies provide new insights for the design of novel therapeutic strategies for asthma treatment.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Células Epiteliais/fisiologia , Miócitos de Músculo Liso/fisiologia , Transdução de Sinais , Asma , Brônquios/citologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas do Citoesqueleto/fisiologia , Receptor DCC/metabolismo , Receptores ErbB/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
18.
Nucleic Acids Res ; 45(8): 4463-4478, 2017 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-28158673

RESUMO

Polydactyl zinc finger (ZF) proteins have prominent roles in gene regulation and often execute multiple regulatory functions. To understand how these proteins perform varied regulation, we studiedDrosophila Suppressor of Hairy-wing [Su(Hw)], an exemplar multifunctional polydactyl ZF protein. We identified separation-of-function (SOF) alleles that encode proteins disrupted in a single ZF that retain one of the Su(Hw) regulatory activities. Through extended in vitro analyses of the Su(Hw) ZF domain, we show that clusters of ZFs bind individual modules within a compound DNA consensus sequence. Through in vivo analysis of SOF mutants, we find that Su(Hw) genomic sites separate into sequence subclasses comprised of combinations of modules, with subclasses enriched for different chromatin features. These data suggest a Su(Hw) code, wherein DNA binding dictates its cofactor recruitment and regulatory output. We propose that similar DNA codes might be used to confer multiple regulatory functions of other polydactyl ZF proteins.


Assuntos
Cromatina/química , DNA/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Proteínas Repressoras/genética , Dedos de Zinco , Alelos , Animais , Sequência de Bases , Sítios de Ligação , Cromatina/efeitos dos fármacos , Cromatina/metabolismo , DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/metabolismo , Metanossulfonato de Etila/farmacologia , Feminino , Regulação da Expressão Gênica , Genótipo , Masculino , Mutagênicos/farmacologia , Mutação , Fenótipo , Ligação Proteica , Domínios Proteicos , Proteínas Repressoras/metabolismo
19.
Zhongguo Zhong Yao Za Zhi ; 44(7): 1410-1415, 2019 Apr.
Artigo em Zh | MEDLINE | ID: mdl-31090299

RESUMO

This research aims to develop an UHPLC method, based on core-shell column(i.e. superficially porous particles), for simultaneous determination of eight isoflavonoids including formononetin,(6αR,11αR)-3-hydroxy-9,10-dimethoxypterocarpan, calycosin-7-O-ß-D-glucopyranoside,(3R)-7,2-dihydroxy-3,4-dimethoxyisoflavone, calycosin, ononin,(6αR,11αR)-9,10-dimethoxypterocarpan-3-O-ß-D-glucopyranoside, and(3R)-7,2-dihydroxy-3,4-dimethoxyisoflavan-7-O-ß-D-glucopyranoside in Astragali Radix. The analysis was performed on an Agilent Poroshell EC-C_(18 )column(2.1 mm×100 mm, 2.7 µm) with 0.2% formic acid solution(A)-acetonitrile(B) as mobile phase for gradient elution. The flow rate was 0.5 mL·min~(-1), with column temperature of 40 ℃ and the wavelengths were set at 260 and 280 nm. According to the results, all calibration curves showed good linearity(R~2>0.999 8) within the tested concentration ranges. Both the intra-and inter-day precisions for 8 isoflavonoids were less than 0.80%, with the mean recovery at the range of 94.71%-104.6%. Thus, the newly developed UHPLC method using core-shell column owned the advantages in terms of rapid analysis, low column pressure and less solvent consumption, thus enabling the usage of conventional HPLC systems. Meanwhile, quantitative evaluation was carried out for 22 batches of commercial Astragali Radix. It has been found that great variations occurred for the content of the individual isoflavonoids among different batches; in contrast, the total content of total 8 isoflavonoids(>0.1%) was stable in most samples, indicating that it was reasonable to involve all isoflavonoids as the chemical markers for the quality control of Astragali Radix.


Assuntos
Astrágalo/química , Medicamentos de Ervas Chinesas/normas , Flavonas/análise , Cromatografia Líquida de Alta Pressão , Compostos Fitoquímicos/análise , Raízes de Plantas/química , Controle de Qualidade
20.
Mol Plant Microbe Interact ; 31(12): 1244-1256, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29905495

RESUMO

OxyR and SoxR are two transcriptional regulators in response to oxidative stress in most bacteria, and SoxR has been reported to be activated by the endogenous redox-cycling compound phenazine in phenazine-producing organisms. However, which transcriptional regulator is activated in pathogens treated with the antibiotic phenazine-1-carboxylic acid (PCA) has not been determined. In this study, we found that PCA treatment activated OxyR rather than SoxR in the phytopathogenic bacteria Xanthomonas oryzae pv. oryzae and X. oryzae pv. oryzicola. We also found that X. oryzae pv. oryzae was much more sensitive to PCA and H2O2 and had a defective antioxidant system (i.e., less of total antioxidant capacity and total catalase activity than X. oryzae pv. oryzicola, although X. oryzae pvs. oryzae and oryzicola are very closely related). Based on KEGG sequences, OxyR differs in 10 amino acids in X. oryzae pv. oryzae versus X. oryzae pv. oryzicola. By exchanging OxyR between X. oryzae pvs. oryzae and oryzicola, we elucidated that OxyR contributed to the differences in antioxidant capacity, total catalase activity, and sensitivity to PCA and H2O2. We also found that OxyR affected X. oryzae pvs. oryzae and oryzicola growth in a nutrient-poor medium, virulence on host plants (rice), and the hypersensitive response on nonhost plants (Nicotiana benthamiana). Thus, OxyR is a critical regulator that relates to the differences in antioxidative stress between X. oryzae pvs. oryzae and oryzicola and contributes to the differences in survival of them against oxidative stress.


Assuntos
Antioxidantes/farmacologia , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Oryza/microbiologia , Doenças das Plantas/microbiologia , Fatores de Transcrição/metabolismo , Xanthomonas/genética , Proteínas de Bactérias/genética , Oryza/efeitos dos fármacos , Fatores de Transcrição/genética , Virulência/genética , Xanthomonas/metabolismo , Xanthomonas/patogenicidade
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