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1.
Ecotoxicol Environ Saf ; 269: 115743, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38035519

RESUMO

Deoxynivalenol (DON) is the most common mycotoxin in food and feed, which can cause undesirable effects, including diarrhea, emesis, weight loss, and growth delay in livestock. Intestinal epithelial cells were the main target of DON, which can cause oxidative stress and inflammatory injury. Tanshinone IIA (Tan IIA) is fat-soluble diterpene quinone, which is the most abundant active ingredient in salvia miltiorrhiza plant with antioxidant and anti-inflammatory characteristics. However, it is not clear whether Tan IIA can protect against or inhibit intestinal oxidative stress and inflammatory injury under DON exposure. This study aimed to explore the protective effect of Tan IIA on DON-induced toxicity in porcine jejunum epithelial cells (IPEC-J2). Cells were exposed to 0, 0.5, 1.0, 2.0 µM DON and/or 45 µg/mL TAN ⅡA to detect oxidative stress indicators. inflammatory cytokines, NF-κB expression, NLRP3 inflammasome and pyroptosis-related factors. In this study, DON exposure caused IPEC-J2 cells oxidative stress by elevating ROS and 8-OHdG content, inhibited GSH-Px activity. Furthermore, DON increased pro-inflammatory factor (TNF-α, IL-1ß, IL-18 and IL-6) expression and decreased the anti-inflammatory factor (IL-10) expression, causing inflammatory response via triggering NF-κB pathway. Interestingly, above changes were alleviated after Tan IIA treatment. In addition, Tan IIA relieved DON-induced pyroptosis by suppressing the expression of pyroptosis-related factors (NLRP3, Caspase-1, GSDMD, IL-1ß, and IL-18). In general, our data suggested that Tan IIA can ameliorate DON-induced intestinal epithelial cells injury associated with suppressing the pyroptosis signaling pathway. Our findings pointed that Tan IIA could be used as the potential therapeutic drugs on DON-induced enterotoxicity.


Assuntos
Abietanos , Interleucina-18 , NF-kappa B , Tricotecenos , Suínos , Animais , NF-kappa B/metabolismo , Interleucina-18/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , Linhagem Celular , Anti-Inflamatórios/farmacologia , Células Epiteliais
2.
J Immunol ; 206(9): 2146-2159, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33846224

RESUMO

Coronavirus disease 2019 (COVID-19) is caused by a novel coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with some patients developing severe illness or even death. Disease severity has been associated with increased levels of proinflammatory cytokines and lymphopenia. To elucidate the atlas of peripheral immune response and pathways that might lead to immunopathology during COVID-19 disease course, we performed a peripheral blood RNA sequencing analysis of the same patient's samples collected from symptom onset to full recovery. We found that PBMCs at different disease stages exhibited unique transcriptome characteristics. We observed that SARS-CoV-2 infection caused excessive release of inflammatory cytokines and lipid mediators as well as an aberrant increase of low-density neutrophils. Further analysis revealed an increased expression of RNA sensors and robust IFN-stimulated genes expression but a repressed type I IFN production. SARS-CoV-2 infection activated T and B cell responses during the early onset but resulted in transient adaptive immunosuppression during severe disease state. Activation of apoptotic pathways and functional exhaustion may contribute to the reduction of lymphocytes and dysfunction of adaptive immunity, whereas increase in IL2, IL7, and IL15 may facilitate the recovery of the number and function of lymphocytes. Our study provides comprehensive transcriptional signatures of peripheral blood response in patients with moderate COVID-19.


Assuntos
COVID-19/sangue , Citocinas/sangue , Progressão da Doença , Mediadores da Inflamação/sangue , Leucócitos Mononucleares/metabolismo , RNA-Seq , SARS-CoV-2/metabolismo , Adulto , Idoso , Feminino , Regulação da Expressão Gênica , Humanos , Leucócitos Mononucleares/virologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade
3.
Ecotoxicol Environ Saf ; 263: 115247, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37453270

RESUMO

The most prevalent contaminated mycotoxin in feed and grain is T-2 toxin. The T-2 toxin's primary action target is the gut because it is the main organ of absorption. T-2 toxin can cause intestinal damage, but, few molecular mechanisms have been elucidated. It is important to discover the key pathways by which T-2 toxin causes enterotoxicity. In this research, IPEC-J2 cells are used as a cell model to investigate the function of the MAPK signaling pathway in T-2 toxin-induced intestinal epithelial cell damage. Throughout this research, T-2 toxin results in functional impairment in IPEC-J2 cells by reducing the TJ proteins Claudin, Occludin-1, ZO-1, N-cadherin, and CX-43 expression. T-2 toxin significantly reduced the survival of IPEC-J2 cells and increased LDH release in a dose-dependent way. T-2 toxin induced IPEC-J2 cell oxidative stress by raising ROS and MDA content, and mitochondrial damage was indicated by a decline in MMP and an increase in the opening degree of MPTP. T-2 toxin upregulated the expression of ERK, P38 and JNK, which triggered the MAPK signaling pathway. In addition, T-2 toxin caused IPEC-J2 cell inflammation responses reflected by increased the levels of inflammation-related factors IL-8, p65, P-p65 and IL-6, and down-regulated IL-10 expression level. Inhibition JNK molecule can ease IPEC-J2 cell functional impairment and inflammatory response. In conclusion, as a consequence of the T-2 toxin activating the JNK molecule, oxidative stress and mitochondrial damage are induced, which impair cellular inflammation.


Assuntos
Toxina T-2 , Humanos , Toxina T-2/toxicidade , Intestinos , Estresse Oxidativo , Transdução de Sinais , Células Epiteliais , Inflamação/induzido quimicamente
4.
Ecotoxicol Environ Saf ; 253: 114695, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36857919

RESUMO

T-2 toxin is an unavoidable food and feed contaminant that seriously threatens human and animal health. Exposure to T-2 toxin can cause testosterone synthesis disorder in male animals, but the molecular mechanism is still not completely clear. The MAPK pathway participates in the regulation of testosterone synthesis by Leydig cells, but it is unclear whether the MAPK pathway participates in T-2 toxin-induced testosterone synthesis disorders. In this research, testosterone synthesis capacity, testosterone synthase expression and MAPK pathway activation were examined in male mice and TM3 cells exposed to T-2 toxin. The results showed that T-2 toxin exposure decreased testicular volume and caused pathological changes in the microstructure and ultrastructure of testicular Leydig cells. T-2 toxin exposure also decreased testicular testosterone content and the protein expression of testosterone synthase. In vitro, T-2 toxin inhibited cell viability and decreased the expression of testosterone synthase in TM3 cells, and it decreased the testosterone contents in cell culture supernatants. Moreover, T-2 toxin activated the MAPK pathway by increasing the expression of p38, JNK and ERK as well as the expression of p-p38, p-JNK and p-ERK in testis and TM3 cells. The p38 molecular inhibitor (SB203580) significantly alleviated the T-2 toxin-induced decrease in testosterone synthase expression in TM3 cells and the T-2 toxin-induced reduction in testosterone content in TM3 cell culture supernatants. In summary, p38 mediates T-2 toxin-induced Leydig cell testosterone synthesis disorder.


Assuntos
Células Intersticiais do Testículo , Toxina T-2 , Masculino , Camundongos , Humanos , Animais , Células Intersticiais do Testículo/metabolismo , Toxina T-2/toxicidade , Testosterona/metabolismo , Testículo/metabolismo , Células Cultivadas
5.
FASEB J ; 35(4): e21394, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33710654

RESUMO

Pyrroloquinoline quinone (PQQ) has a variety of biological functions. However, rare attention has been paid to its effects on exercise-induced damage. Here, we assessed the potential protective effects of PQQ against the fatigue and oxidative damage caused by repeated exhaustive exercise, and studied the underlying mechanism. The models for exercise-induced fatigue were established, and the parameters were measured, including the time to exhaustion (TTE), biochemical indicators, the expression of nuclear factor kappa B (NF-κB) and inflammatory cytokines and so on. Besides, the mitochondrial function was evaluated by the morphology, membrane potential, respiratory function, adenosine triphosphate (ATP) levels, and the application of the mitochondrial complex I inhibitor. The results demonstrate that PQQ prolongs TTE, causes the decrease in the activity of serum creatine kinase and lactate dehydrogenase, increases the activity of antioxidant enzymes, inhibits the production of reactive oxygen species (ROS) and malondialdehyde (MDA), and diminishes the over expression of NF-κB (p65) and inflammatory mediators. Furthermore, PQQ preserves normal mitochondrial function. Particularly, PQQ reduces the accumulation of ROS triggered by the mitochondrial complex I inhibitor. These data suggest that PQQ can significantly protect mice from exercise-induced fatigue and oxidative damage by improving mitochondrial function. These data also suggest that PQQ controls mitochondrial activity through directly affecting the NADH dehydrogenase.


Assuntos
Fadiga/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Cofator PQQ/farmacologia , Condicionamento Físico Animal , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Masculino , Camundongos , Mioblastos/efeitos dos fármacos , NF-kappa B/genética , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo
6.
Ecotoxicol Environ Saf ; 248: 114291, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36395652

RESUMO

Deoxynivalenol (DON) is universally detected trichothecene in most cereal commodities, which is considered as a major hazardous material for human and animal health. Intestine is the most vulnerable organ with higher concentration of DON than other organs, owing to the first defense barrier function to exogenous substances. However, the underling mechanisms about DON-induced intestinal toxicity remain poorly understood. Here, DON poisoning models of IPEC-J2 cells was established to explore adverse effect and the potential mechanism of DON-induced enterotoxicity. Results showed that DON exposure destroyed IPEC-J2 cells morphology. Results showed that DON exposure destroyed IPEC-J2 cells morphology. Intestinal epithelial barrier injury was caused by DON with increasing LDH release, decreasing cell viability as well decreasing tight junction protein expressions (Occludin, N-Cad, ZO-1, Claudin-1 and Claudin-3). Moreover, DON caused mitochondrial dysfunction by opening mitochondrial permeability transition pore and eliminating mitochondrial membrane potential. DON exposure upregulated protein and mRNA expression of mitochondrial fission factors (Drp1, Fis1, MIEF1 and MFF) and mitophagy factors (PINK1, Parkin and LC3), downregulated mitochondrial fusion factors (Mfn1, Mfn2, except OPA1), resulting in mitochondrial dynamics imbalance and mitophagy. Overall, these findings suggested that DON induced tight junction dysfunction in IPEC-J2 cells was related to mitochondrial dynamics-mediated mitophagy.


Assuntos
Dinâmica Mitocondrial , Mitofagia , Humanos , Suínos , Animais , Junções Íntimas , Ocludina , Fatores de Alongamento de Peptídeos , Proteínas Mitocondriais
7.
Small ; 17(24): e2100969, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33938137

RESUMO

Solar-driven evaporation is regarded as a sustainable wastewater treatment strategy for clean water recovery and salt condensation. However, achieving both high evaporation rate and long-term stability remain challenging due to poor thermal management and rapid salt accumulation and blocking. Here, a T-shape solar-driven evaporator, composed of a surface-carbonized longitudinal wood membrane (C-L-wood) is demonstrated as the top "" for solar harvesting/vapor generation/salt collection and another piece of natural L-wood as the support "" for brine transporting and thermally insulating. The horizontally aligned micro-channels of C-L-wood have a low perpendicular thermal conductivity and can effectively localize the thermal energy for rapid evaporation. Meanwhile, the brine is guided to transport from the support L-wood ("") to the centerline of the top evaporator and then toward the double edge (""), during which clean water is evaporated and salt is crystallized at the edge. The T-shape evaporator demonstrates a high evaporation rate of 2.43 kg m-2 h-1 under 1 sun irradiation, and is stable for 7 days of the outdoor operation, which simultaneously realizes clean water evaporation and salt collection (including Cu2+ , CrO42- , Co2+ ), and achieves zero-liquid discharge. Therefore, the T-shape design provides an effective strategy for high performance wastewater treatment.


Assuntos
Energia Solar , Purificação da Água , Luz Solar , Água , Madeira
8.
J Med Virol ; 93(4): 2505-2512, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33433006

RESUMO

To investigate the dynamic changes of Krebs von den Lungen-6 (KL-6) among patients with coronavirus disease 2019 (COVID-19) and the role of KL-6 as a noninvasive biomarker for predicting long-term lung injury, the clinical information and laboratory tests of 166 COVID-19 patients were collected, and a correlation analysis between KL-6 and other parameters was conducted. There were 17 (10.2%, 17/166) severe/critical and 149 (89.8%, 149/166) mild COVID-19 patients in our cohort. Serum KL-6 was significantly higher in severe/critical COVID-19 patients than in mild patients (median 898.0 vs. 451.2 U/ml, p < .001). KL-6 was next confirmed to be a sensitive and specific biomarker for distinguishing mild and severe/critical patients and correlate to computed tomography lung lesions areas. Serum KL-6 concentration during the follow-up period (>100 days postonset) was well correlated to those concentrations within 10 days postonset (Pearson r = .867, p < .001), indicating the prognostic value of KL-6 levels in predicting lung injury after discharge. Finally, elevated KL-6 was found to be significantly correlated to coagulation disorders, and T cells subsets dysfunctions. In summary, serum KL-6 is a biomarker for assessing COVID-19 severity and predicting the prognosis of lung injury of discharged patients.


Assuntos
COVID-19/sangue , Lesão Pulmonar/sangue , Mucina-1/sangue , Adulto , Idoso , Biomarcadores/sangue , COVID-19/diagnóstico por imagem , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Lesão Pulmonar/diagnóstico por imagem , Lesão Pulmonar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , SARS-CoV-2/isolamento & purificação , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X/métodos
9.
J Org Chem ; 86(21): 14572-14585, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34623805

RESUMO

A novel visible-light-induced coupling-cyclization of ortho-alkynylaryl vinylethers with arylsulfonyl azides has been described. This transformation provided a concise approach to access C3-exocyclic C═C bond/C2-alkylsulfone-tethered benzofurans via a solvent-leveraged carbosulfonylation and [2 + 2 + 3] cyclization. Primary mechanistic studies demonstrated that THF belongs to a crucial H atom source.

10.
Org Biomol Chem ; 18(5): 956-963, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-31930235

RESUMO

A Brønsted acid/visible-light-promoted Markovnikov hydroamination of vinylarenes with arylamines in the presence of TPT and CF3CO2H has been developed. This transformation provides a green approach to alpha-amino-substituted arylalkanes under metal-free conditions.

11.
J Exp Bot ; 70(1): 193-204, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30295847

RESUMO

FLOWERING LOCUS T2 (FT2) is the closest paralog of the FT1 flowering gene in the temperate grasses. Here we show that overexpression of FT2 in Brachypodium distachyon and barley results in precocious flowering and reduced spikelet number, while down-regulation by RNA interference results in delayed flowering and a reduced percentage of filled florets. Similarly, truncation mutations of FT2 homeologs in tetraploid wheat delayed flowering (2-4 d) and reduced fertility. The wheat ft2 mutants also showed a significant increase in the number of spikelets per spike, with a longer spike development period potentially contributing to the delayed heading time. In the wheat leaves, FT2 was expressed later than FT1, suggesting a relatively smaller role for FT2 in the initiation of the reproductive phase. FT2 transcripts were detected in the shoot apical meristem and increased during early spike development. Transversal sections of the developing spike showed the highest FT2 transcript levels in the distal part, where new spikelets are formed. Our results suggest that, in wheat, FT2 plays an important role in spike development and fertility and a limited role in the timing of the transition between the vegetative and reproductive shoot apical meristem.


Assuntos
Brachypodium/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Hordeum/genética , Proteínas de Plantas/genética , Triticum/genética , Brachypodium/crescimento & desenvolvimento , Fertilidade/genética , Flores/genética , Genes de Plantas/genética , Hordeum/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Reprodução/genética , Triticum/crescimento & desenvolvimento
12.
Org Biomol Chem ; 17(29): 7042-7054, 2019 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-31304502

RESUMO

A sequential Rh(i)-catalyzed vinylation/[2 + 1]carbocyclization between enynes and diazo compounds has been developed. This transformation features a wide range of enynes and acceptor/acceptor diazo compounds, providing easy access to versatile vinyl-substituted azabicyclo[3.1.0]hexanes having a broad tolerance to functional groups.

13.
Environ Sci Technol ; 53(5): 2705-2712, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30726066

RESUMO

Organic contaminants in water have become one of the most serious environmental problems worldwide. Adsorption is one of the most promising approaches to remove organic pollutants from water. However, the existing adsorbents have relatively low removal efficiency, complex preparation processes, and high cost, which limit their practical applications. Here, we developed three-dimensional (3D) zirconium metal-organic frameworks (MOFs) encapsulated in a natural wood membrane (UiO-66/wood membrane) for highly efficient organic pollutant removal from water. UiO-66 MOFs were in situ grown in the 3D low-tortuosity wood lumens by a facile solvothermal strategy. The resulting UiO-66/wood membrane contains the highly mesoporous UiO-66 MOF structure as well as many elongated and open lumens along the direction of the wood growth. Such a unique structural feature improves the mass transfer of organic pollutants and increases the contact probability of organic contaminants with UiO-66 MOFs as the water flows through the membrane, thereby improving the removal efficiency. Furthermore, the integrated multilayer filter consisting of three pieces of UiO-66/wood membranes exhibits a high removal efficiency (96.0%) for organic pollutants such as rhodamine 6G, propranolol, and bisphenol A at the flux of 1.0 × 103 L·m-2·h-1. The adsorbed capacity of UiO-66/wood for Rh6G (based on the content of UiO-66 MOFs) is calculated to be 690 mg·g-1. We believe that such low-cost and scalable production of the UiO-66/wood membrane has broad applications for wastewater treatment and other related pollutant removal.


Assuntos
Poluentes Ambientais , Estruturas Metalorgânicas , Poluentes Químicos da Água , Adsorção , Madeira
14.
Anal Chem ; 90(7): 4909-4915, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29516723

RESUMO

Wood has attracted increasing scientific interest in the field of green electronics, biological devices, bioenergy, and energy storage because of its abundance, low cost, biocompatibility, and natural vessel structure. However, its potential application in the important area of environmental monitoring has not yet been effectively explored. In this work, gold nanoparticles (NPs) encapsulated in porous wood (denoted as Au@wood) for high-performance colorimetric detection of Hg2+ in aqueous solution have been constructed. The detection mechanism is based on Hg2+-triggered methylene blue (MB) reduction-assisted signal amplification. In such a detection system, Au NPs can be used as a specific identification element for the binding of Hg2+ due to the formation of gold amalgam to initiate catalytic activity of gold. The low-cost natural wood is introduced to prevent the aggregation of Au NPs and increase the contact area between MB and Au NPs in three-dimensional space. MB, as a tracer molecule, enables the output signals to be directly observed by the naked eye. Such a detection system exhibited an ultralow detection limit of 32 pM for Hg2+, which is greatly lower than the threshold levels (10 nM) for drinking water and other colorimetric methods. The proposed detection system also exhibits high selectivity against other metal ions and works well for environmental water and blood samples. The resultant Au@wood sensor is low cost, easy handling, and convenient, making it an attractive material for point-of-use monitoring of Hg2+ in environmental and biological samples.

15.
Anal Chem ; 90(5): 3621-3627, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29446622

RESUMO

A reasonable and efficient strategy for the construction of hyper-cross-linked porous MoS2-CD-polymer frameworks (MoS2CDPFs) was demonstrated. Here, MoS2 nanosheets (NSs) can be decorated with amino functionalized ß-cyclodextrin, producing a nanoscale structural motif (MoS2@CD) for the synthesis of MoS2CDPFs. We demonstrated that CD polymer (CDP) as linker can be uniformly incorporated into the frameworks. Except for the pores created between MoS2 NSs, polymer doping generates extra interspace between MoS2 NSs and CD monomer. Interestingly, the resultant MoS2CDPFs can rapidly sequester aromatic phenolic micropollutant bisphenol A (0.1 mM) from water with 93.2% adsorption capacity, which is higher than that of MoS2, MoS2@CD, and CDP. The intercalation between MoS2 sheets with CDP imparts the frameworks durability in adsorption/desorption of aromatic phenolic micropollutants. Remarkably, the removal efficiency reduced only 3% after 10 regeneration-reuse cycles. These findings demonstrated that the porous MoS2-CD-polymer-based frameworks are promising adsorbents for rapid, flow-through water remediation.

16.
Anal Chem ; 89(15): 8140-8147, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28682588

RESUMO

Portable, low-cost, and quantitative detection of cancer cells at home and in the field has the potential to revolutionize medical diagnostics. We first report the design and synthesis of highly efficient folic-acid-conjugated hydrogen-generation tube-in-tube CuO/Co3O4 heterojunction nanofibers for highly sensitive and rapid recognition of cancer cells through a pressure signal under visible-light irradiation. The resultant nanofibers can dramatically enhance the hydrogen-generation activity of ammonia borane under visible-light irradiation. Such hydrogen-generation reaction can translate a molecular recognition event between folic acid and folate receptor to measurable pressure signal readout through a low-cost and portable pressure meter for target cancer cell detection. Limits of detection (LODs) down to 50 cells mL-1 in only 15 min can be achieved. This result is superior to those of the other reported methods, indicating the superiority of the new pressure-based sensor in terms of sensitivity. The present study establishes the pressure meter as a useful tool for early clinical point-of-care cancer diagnosis.


Assuntos
Cobalto/química , Cobre/química , Técnicas Eletroquímicas , Hidrogênio/análise , Nanofibras/química , Óxidos/química , Animais , Catálise , Ácido Fólico/química , Células HeLa , Humanos , Hidrogênio/metabolismo , Limite de Detecção , Camundongos , Microscopia Confocal , Células NIH 3T3 , Pressão , Teoria Quântica
17.
Chemistry ; 23(37): 8879-8885, 2017 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-28444937

RESUMO

Self-assembly has emerged as a promising method to control the structure and properties of ensembles of inorganic nanoparticles (NPs) for exploiting their collective effects. However, the rational assembly of inorganic NPs into soluble porous architectures for use as homogenized heterogeneous catalysts has been less studied. Herein, it is shown that inorganic NPs can be used for the assembly of soluble porous coordination frameworks (PCFs) by atom-scale interfacial coordination-driven assembly. Owing to their large pore size, high dispersity in solution, strong absorption in the near-infrared (NIR) range, and long-lived electron-hole pair, the obtained soluble frameworks could serve as a platform for homogenized heterogeneous photocatalysts, which exhibited excellent activity, high apparent quantum efficiency, and recyclability in the catalysis of the noble-metal-free Suzuki coupling reactions under NIR light at room temperature. Moreover, PCF catalysts can be reused more than five times without significant loss of activity, which indicates long-term stability. The present strategy to fabricate soluble porous nanostructures opens a new chemical toolbox for homogenized heterogeneous catalysts and may bring new inspiration to photocatalysis.

18.
Org Biomol Chem ; 15(36): 7710-7714, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28875217

RESUMO

Catalytic amounts of TBHP (15 mol%) promoted tribromomethylation of activated alkenes has been developed. This method provided a metal-free aerobic way to construct tribromomethylated 2-oxindoles from the reaction of readily available N-arylacrylamides with CBr4via a proposed tandem radical cyclization process. Air is used as an efficient terminal oxidant in this transformation. The formation of 1,1-dibromoolefin derivatives was also realized at higher temperature under neat conditions.

19.
Kidney Blood Press Res ; 42(2): 369-378, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28624830

RESUMO

BACKGROUND/AIMS: Diabetes mellitus can exacerbate renal ischemia-reperfusion (I/R) injury (RI/RI). The aim of the present study was to evaluate the protective effect of GSK-3ß inhibition (TDZD-8) on I/R-induced renal injury through the Nrf2/HO-1 pathway in a streptozocin (STZ)-induced diabetic rat model. METHODS: STZ-induced diabetic rats preconditioned with TDZD-8 and ZnPP were subjected to renal I/R. The extent of renal morphologic lesions. Renal function was assessed from blood urea nitrogen (BUN) and serum creatinine (Scr), as determined utlizing commercial kits. Oxidative stress and inflammatory activity in the kidney tissue was estimated from levels of malondialdehyde (MDA), interleukin-10 (IL-10), tumor necrosis factor-α (TNF-α), and nitric oxide (NO), as well as the activities of superoxide dismutase (SOD) and glutathione (GSH) using qRT-PCR and ELISA. The expressions of Nrf2, HO-1, Bcl-2 and NF-κB in the renal tissue were measured by qRT-PCR and western blotting. RESULTS: I/R-induced renal inflammation was reduced significantly by TDZD-8 pretreatment. Preconditioning with TDZD-8 suppressed NF-κB expression and enhanced Bcl-2 expression in the renal tissue. The upregulated level of malondialdehyde (MDA), and reduced activities of superoxide dismutase (SOD) and glutathione (GSH) in I/R-shocked rats were markedly restored by TDZD-8 pretreatment. Furthermore, pretreatment with TDZD-8 enhanced activation of the Nrf2/HO-1 pathway in the renal tissue of diabetic RI/RI rats. CONCLUSION: These findings suggest that preconditioning with TDZD-8 may protect the kidney from I/R-induced damage via the activation of the Nrf2/HO-1 pathway in STZ-induced diabetic rats. Further detailed studies are needed to further clarify the underlying mechanisms.


Assuntos
Complicações do Diabetes/prevenção & controle , Glicogênio Sintase Quinase 3 beta/fisiologia , Heme Oxigenase (Desciclizante)/metabolismo , Rim/lesões , Fator 2 Relacionado a NF-E2/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Animais , Diabetes Mellitus/induzido quimicamente , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Precondicionamento Isquêmico/métodos , Rim/patologia , Ratos , Tiadiazóis/uso terapêutico
20.
Chemistry ; 21(15): 5723-6, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25707447

RESUMO

A novel CBr4-mediated dehydrogenative Povarov/aromatization tandem reaction of glycine derivatives with alkenes, leading to complex quinoline derivatives, and a CBr4-mediated dehydrogenative C-H functionalization of N-aryl tetrahydroisoquinolines with nucleophiles to form C-C and C-P bonds are reported. The reactions were performed under very simple and mild reaction conditions; only CBr4 was used as a promoter. A plausible mechanism involving a radical process is proposed.

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