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1.
Synth Syst Biotechnol ; 9(3): 540-548, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38680947

RESUMO

The chromosomal position effect can significantly affect the transgene expression, which may provide an efficient strategy for the inauguration of alien genes in new hosts, but has been less explored rationally. The bacterium Myxococcus xanthus harbors a large circular high-GC genome, and the position effect in this chassis may result in a thousand-fold expression variation of alien natural products. In this study, we conducted transposon insertion at TA sites on the M. xanthus genome, and used enrichment and dilution indexes to respectively appraise high and low expression potentials of alien genes at insertion sites. The enrichment sites are characteristically distributed along the genome, and the dilution sites are overlapped well with the horizontal transfer genes. We experimentally demonstrated the enrichment sites as high expression integration sites (HEISs), and the dilution sites unsuitable for gene integration expression. This work highlights that HEISs are the plug-and-play sites for efficient expression of integrated genes.

2.
Nat Commun ; 15(1): 1267, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341421

RESUMO

Developing heterogeneous photocatalysts for the applications in harsh conditions is of high importance but challenging. Herein, by converting the imine linkages into quinoline groups of triphenylamine incorporated covalent organic frameworks (COFs), two photosensitive COFs, namely TFPA-TAPT-COF-Q and TFPA-TPB-COF-Q, are successfully constructed. The obtained quinoline-linked COFs display improved stability and photocatalytic activity, making them suitable photocatalysts for photocatalytic reactions under harsh conditions, as verified by the recyclable photocatalytic reactions of organic acid involving oxidative decarboxylation and organic base involving benzylamine coupling. Under strong oxidative condition, the quinoline-linked COFs show a high efficiency up to 11831.6 µmol·g-1·h-1 and a long-term recyclable usability for photocatalytic production of H2O2, while the pristine imine-linked COFs are less catalytically active and easily decomposed in these harsh conditions. The results demonstrate that enhancing the linkage robustness of photoactive COFs is a promising strategy to construct heterogeneous catalysts for photocatalytic reactions under harsh conditions.

3.
Small ; 19(44): e2303324, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37391273

RESUMO

Converting CO2 into value-added chemicals to solve the issues caused by carbon emission is promising but challenging. Herein, by embedding metal ions (Co2+ , Ni2+ , Cu2+ , and Zn2+ ) into an imidazole-linked robust photosensitive covalent organic framework (PyPor-COF), effective photocatalysts for CO2 conversion are rationally designed and constructed. Characterizations display that all of the metallized PyPor-COFs (M-PyPor-COFs) display remarkably high enhancement in their photochemical properties. Photocatalysis reactions reveal that the Co-metallized PyPor-COF (Co-PyPor-COF) achieves a CO production rate as high as up to 9645 µmol g-1 h-1 with a selectivity of 96.7% under light irradiation, which is more than 45 times higher than that of the metal-free PyPor-COF, while Ni-metallized PyPor-COF (Ni-PyPor-COF) can further tandem catalyze the generated CO to CH4 with a production rate of 463.2 µmol g-1 h-1 . Experimental analyses and theory calculations reveal that their remarkable performance enhancement on CO2 photoreduction should be attributed to the incorporated metal sites in the COF skeleton, which promotes the adsorption and activation of CO2 and the desorption of generated CO and even reduces the reaction energy barrier for the formation of different intermediates. This work demonstrates that by metallizing photoactive COFs, effective photocatalysts for CO2 conversion can be achieved.

4.
Small ; 19(34): e2301998, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37162443

RESUMO

In order to overcome the limitations of supramolecular organic cages for their incomplete accessibility of active sites in the solid state and uneasy recyclability in liquid solution, herein a nitrogen-rich organic cage is rationally linked into framework systems and four isoreticular covalent organic frameworks (COFs), that is, Cage-TFB-COF, Cage-NTBA-COF, Cage-TFPB-COF, and Cage-TFPT-COF, are successfully synthesized. Structure determination reveals that they are all high-quality crystalline materials derived from the eclipsed packing of related isoreticular two-dimensional frameworks. Since the nitrogen-rich sites usually have a high affinity toward iodine species, iodine adsorption investigations are carried out and the results show that all of them display an enhancement in iodine adsorption capacities. Especially, Cage-NTBA-COF exhibits an iodine adsorption capacity of 304 wt%, 14-fold higher than the solid sample packed from the cage itself. The strong interactions between the nitrogen-rich sites and the adsorbed iodine species are revealed by spectral analyses. This work demonstrates that, utilizing the reticular chemistry strategy to extend the close-packed supramolecular organic cages into crystalline porous framework solids, their inherent properties can be greatly exploited for targeted applications.

5.
ACS Nano ; 16(12): 21565-21575, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36472955

RESUMO

Developing effective photosensitizers to initiate the generation of singlet oxygen (1O2) is of great significance in both chemistry and physiology. Herein, linking the photoactive porphyrin moieties by in situ-formed robust imidazole groups, a covalent organic framework (COF), PyPor-COF, was successfully designed and synthesized. Detailed characterizations reveal that it not only possesses high crystallinity, permanent porosity, and robust stability but also shows a semiconductive photoresponse activity. As demonstrated by electron paramagnetic resonance experiments, the COF can initiate the generation of 1O2 efficiently under visible-light irradiation, the efficiency of which is higher than that of the pristine porphyrin-based reactant and even higher than some commonly used commercially available photosensitizing agents. Anticancer experiments prove that it can efficiently trigger the production of 1O2 in a physiological environment. This work demonstrates that the imidazole-linked porphyrin-incorporated COF is a highly promising photosensitizer that can even be applied in photodynamic therapy.


Assuntos
Estruturas Metalorgânicas , Fotoquimioterapia , Porfirinas , Oxigênio Singlete , Estruturas Metalorgânicas/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Porfirinas/farmacologia , Porfirinas/química , Imidazóis/farmacologia
6.
Front Plant Sci ; 13: 985088, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262653

RESUMO

Drought stress is one of the major abiotic stress factors that affect plant growth and crop productivity. Tartary buckwheat is a nutritionally balanced and flavonoid-rich pseudocereal crop and also has strong adaptability to different adverse environments including drought. However, little is known about its drought tolerance mechanism. In this study, we performed comparative physiological and transcriptomic analyses of two contrasting drought-resistant Tartary buckwheat genotypes under nature drought treatment in the reproductive stage. Under drought stress, the drought-tolerant genotype XZSN had significantly higher contents of relative water, proline, and soluble sugar, as well as lower relative electrolyte leakage in the leaves than the drought-susceptible LK3. A total of 5,058 (2,165 upregulated and 2,893 downregulated) and 5,182 (2,358 upregulated and 2,824 downregulated) potential drought-responsive genes were identified in XZSN and LK3 by transcriptome sequencing analysis, respectively. Among the potential drought-responsive genes of XZSN, 1,206 and 1,274 genes were identified to be potential positive and negative contributors for XZSN having higher drought resistance ability than LK3. Furthermore, 851 out of 1,206 positive drought-resistant genes were further identified to be the core drought-resistant genes of XZSN based on WGCNA analysis, and most of them were induced earlier and quicker by drought stress than those in LK3. Functional annotation of the 851 core drought-resistant genes found that a large number of stress-responsive genes were involved in TFs, abscisic acid (ABA) biosynthesis, signal transduction and response, non-ABA signal molecule biosynthesis, water holding, oxygen species scavenging, osmotic adjustment, cell damage prevention, and so on. Transcriptional regulatory network analyses identified the potential regulators of these drought-resistant functional genes and found that the HD-ZIP and MYB TFs might be the key downstream TFs of drought resistance in Tartary buckwheat. Taken together, these results indicated that the XZSN genotype was more drought-tolerant than the LK3 genotype as evidenced by triggering the rapid and dramatic transcriptional reprogramming of drought-resistant genes to reduce water loss, prevent cell damage, and so on. This research expands our current understanding of the drought tolerance mechanisms of Tartary buckwheat and provides important information for its further drought resistance research and variety breeding.

7.
Front Endocrinol (Lausanne) ; 13: 907874, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36017318

RESUMO

Background: Establishing a successful pregnancy depends on the endometrium and the embryo. It is estimated that suboptimal endometrial receptivity account for one-third of implantation failures. Despite the indepth understanding of the processes associated with embryo-endometrial cross-talk, little progress has been achieved for diagnosis and treatments for suboptimal endometrial receptivity. Methods: This retrospective study included women undergoing their first frozen-thawed embryo transfer (FET) cycles at our reproductive medicine center from March 2021 to August 2021. Transvaginal three-dimensional (3D) ultrasound was performed in the morning on the day of embryo transfer for all the thawed embryo transfer patients, to evaluate endometrial receptivity, including endometrial thickness, echogenicity, volume, movement and blood flow. Results: A total number of 562 patients of FET with 315 pregnancies (56.0%) was analyzed. It was found that only the echo of the endometrial central line was different between the pregnant group and non-pregnant group. Other parameters, such as endometrial thickness, volume, endometrial peristalsis, or the endometrial blood flow were not statistically different between the two groups. Then, according to the relationship between the different groups and the clinical pregnancy rate, a score of 0 to 2 was respectively scored. The sum of the scores for the six items was the patient's endometrial receptivity score. It showed that the clinical pregnancy rate increased as the endometrial receptivity score increased, and when the receptivity score reaches at least 5, the clinical pregnancy rate is significantly improved (63.7% versus 49.5%, P=0.001). Conclusion: We developed an endometrial receptivity scoring system and demonstrated its validity. It may aid clinicians in choosing the useful marker in clinical practice and for informing further research.


Assuntos
Endométrio , Peristaltismo , Transferência Embrionária/métodos , Endométrio/diagnóstico por imagem , Feminino , Humanos , Gravidez , Estudos Retrospectivos , Ultrassonografia
8.
Clinics (Sao Paulo) ; 76: e2942, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669873

RESUMO

OBJECTIVES: This study assessed the protective effect of calcium dobesilate against contrast-induced nephropathy (CIN) after coronary angiography (CAG) or percutaneous coronary intervention (PCI) in patients with diabetes and chronic kidney disease (CKD). METHODS: A total of 130 patients with diabetes and CKD estimated glomerular filtration rate: 30-90 mL/min/1.73m2 were enrolled and included in the analysis. They were divided into experimental (n=65) and control groups (n=65). Patients in the experimental group were administered oral calcium dobesilate (500 mg) three times daily for 2 days before and 3 days after the procedure. The serum creatinine (SCr), cystatin C (Cys C), and neutrophil gelatinase-associated lipocalin (NGAL) levels were measured before and after the procedure. RESULTS: The mean SCr level at 24h after the procedure was found to be significantly lower in the experimental group than in the control group (79.1±19.6 µmol/L vs. 87.0±19.3 µmol/L, p=0.023). However, the Cys C and NGAL levels were not significantly different between the two groups at all measurement time points (all p>0.05). The incidence of CIN defined by the SCr level was significantly lower in the experimental group than in the control group (3 [4.6%] vs. 13 [20.0%], p=0.017). However, the incidence of CIN defined by the Cys C level was not statistically different between the two groups (7 [10.8%] vs. 7 [10.8%], p=1.000). CONCLUSIONS: This study revealed that calcium dobesilate has no preventive effect against CIN in patients with diabetes and CKD.


Assuntos
Dobesilato de Cálcio , Diabetes Mellitus , Nefropatias , Intervenção Coronária Percutânea , Insuficiência Renal Crônica , Biomarcadores , Meios de Contraste/efeitos adversos , Angiografia Coronária , Creatinina , Taxa de Filtração Glomerular , Humanos , Insuficiência Renal Crônica/complicações
9.
Huan Jing Ke Xue ; 42(9): 4441-4451, 2021 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-34414744

RESUMO

Heavy metals in farmland soil are one of the most hazardous pollutants in the environment, owing to their universality and irreversibility. Modified biochar has been widely used in the adsorption and immobilization of heavy metals in soil, and its applicability is mainly determined by the types of heavy metals, pollution levels, and soil environmental conditions. Soil pollution is gradually becoming more complex and diversified, and heavy metal pollutants mostly occur in the form of compound pollution. However, most studies have focused on single heavy metal pollutant or the addition of heavy metal to soil. This study used rice straw as a raw material to prepare biochar, and modified it with K3PO4, KMnO4, and NaOH. The physicochemical and structural characteristics of the modified biochars were detected using a BET accelerated surface area and porosimetry system, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and the biochars were then analyzed for the availability and forms of Cd and Cu in soils contaminated with heavy metals in the mining area. The results showed that the surface roughness of the modified biochar increased to different degrees with increases in specific surface area and pore volume, with the NaOH modified biochar showing the most significant increases from 4.96 m2·g-1 to 60.79 m2·g-1, and from 0.02 cm3·g-1 to 0.12 cm3·g-1, respectively. The pore diameter changed in the opposite direction. The absorption peaks of the functional groups of the modified biochar were all changed, with K3PO4 modified biochar exhibiting the greatest degree of change. The addition of biochar significantly improved the soil pH value (P<0.05), and the pH value of the soil treated with K3PO4 modified biochar exhibited the largest increase. With an application of 20.5% K3PO4 modified biochar, the availability of Cu and Cd in the soil was significantly reduced, by 75.44% and 67.70%, respectively. The immobilization efficiency of Cu was much higher than that of Cd. The best immobilization efficiency of Cu and Cd in soil was achieved with K3PO4 modified biochar. With an addition of 2% K3PO4 modified biochar, the immobilization efficiency of Cu and Cd was 61.06% and 4.12%, respectively. In summary, K3PO4 modified biochar had a better immobilization effect on both Cu and Cd in compound contaminated soil.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo , Cádmio , Carvão Vegetal , Poluição Ambiental/prevenção & controle , Fazendas , Solo , Poluentes do Solo/análise , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Perfusion ; 36(2): 122-129, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32522095

RESUMO

BACKGROUND: Periprocedural myocardial infarction is a common complication following percutaneous coronary intervention. The present study was conducted with an aim to compare the safety and efficacy of loading doses of ticagrelor versus clopidogrel in preventing periprocedural myocardial infarction in Asian patients with acute coronary syndrome undergoing elective percutaneous coronary intervention. METHODS: A total of 114 patients with acute coronary syndrome undergoing elective percutaneous coronary intervention were assigned to clopidogrel group (n = 57, the loading and maintenance doses were 300 and 75 mg qd for clopidogrel, and 300 and 100 mg qd for aspirin), or ticagrelor group (n = 57, the loading and maintenance doses were 180 and 90 mg bid for ticagrelor, and 300 and 100 mg qd for aspirin). Cardiac biomarkers were measured before, 8 hours, and 24 hours after percutaneous coronary intervention. The percutaneous coronary intervention-related periprocedural myocardial infarction was defined according to the fourth universal definition of myocardial infarction (2018). RESULTS: The overall incidence of percutaneous coronary intervention-related periprocedural myocardial infarction was 21.1%. The ticagrelor group showed a significantly lower incidence of periprocedural myocardial infarction (12.3% vs 29.8%, p = 0.022) and numerically lower bleeding events (3.5% vs 8.8%, p = 0.242) as compared with clopidogrel group. No patient had major adverse cardiovascular events during the 1-month follow-up. The levels of high-sensitivity C-reactive protein did not differ significantly between the two groups (p > 0.05), indicating that the benefits of ticagrelor were not from its anti-inflammatory effects. Multivariable analysis showed that the use of ticagrelor (odds ratio: 0.50; 95% confidence interval: 0.29-0.87; p = 0.014) and number of stents (odds ratio: 2.75; 95% confidence interval: 1.25-6.06; p = 0.012) were independent predictors of periprocedural myocardial infarction. CONCLUSION: Pretreatment with a loading dose of ticagrelor seems to be superior in reducing the incidence of percutaneous coronary intervention-related periprocedural myocardial infarction in Asian patients with acute coronary syndrome as compared with clopidogrel.


Assuntos
Síndrome Coronariana Aguda , Clopidogrel/administração & dosagem , Infarto do Miocárdio , Intervenção Coronária Percutânea , Ticagrelor/administração & dosagem , Síndrome Coronariana Aguda/tratamento farmacológico , Humanos , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/prevenção & controle , Intervenção Coronária Percutânea/efeitos adversos , Inibidores da Agregação Plaquetária/administração & dosagem , Resultado do Tratamento
11.
Clinics ; 76: e2942, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1345813

RESUMO

OBJECTIVES: This study assessed the protective effect of calcium dobesilate against contrast-induced nephropathy (CIN) after coronary angiography (CAG) or percutaneous coronary intervention (PCI) in patients with diabetes and chronic kidney disease (CKD). METHODS: A total of 130 patients with diabetes and CKD estimated glomerular filtration rate: 30-90 mL/min/1.73m2 were enrolled and included in the analysis. They were divided into experimental (n=65) and control groups (n=65). Patients in the experimental group were administered oral calcium dobesilate (500 mg) three times daily for 2 days before and 3 days after the procedure. The serum creatinine (SCr), cystatin C (Cys C), and neutrophil gelatinase-associated lipocalin (NGAL) levels were measured before and after the procedure. RESULTS: The mean SCr level at 24h after the procedure was found to be significantly lower in the experimental group than in the control group (79.1±19.6 μmol/L vs. 87.0±19.3 μmol/L, p=0.023). However, the Cys C and NGAL levels were not significantly different between the two groups at all measurement time points (all p>0.05). The incidence of CIN defined by the SCr level was significantly lower in the experimental group than in the control group (3 [4.6%] vs. 13 [20.0%], p=0.017). However, the incidence of CIN defined by the Cys C level was not statistically different between the two groups (7 [10.8%] vs. 7 [10.8%], p=1.000). CONCLUSIONS: This study revealed that calcium dobesilate has no preventive effect against CIN in patients with diabetes and CKD.


Assuntos
Humanos , Dobesilato de Cálcio , Diabetes Mellitus , Insuficiência Renal Crônica/complicações , Intervenção Coronária Percutânea , Nefropatias , Biomarcadores , Angiografia Coronária , Meios de Contraste/efeitos adversos , Creatinina , Taxa de Filtração Glomerular
12.
Oncol Res ; 27(5): 583-592, 2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31053181

RESUMO

This study evaluated the difference in treatment response and survival profiles between drug-eluting bead transarterial chemoembolization (DEB-TACE) and conventional transarterial chemoembolization (cTACE) treatments in Chinese hepatocellular carcinoma (HCC) patients. A total of 120 HCC patients were consecutively enrolled in this prospective cohort study, which showed that DEB-TACE achieved higher complete response (CR) (30.8%) compared with cTACE (7.4%) with no difference in overall response rate (ORR) for patients treated with DEB-TACE and cTACE (80.8% vs. 73.5%). In addition, DEB-TACE was associated with a lower rate of progressive disease (PD) compared with cTACE (1.9% vs. 11.8%). With respect to survival, patients in the DEB-TACE group achieved median progression-free survival (PFS) of 15 months (95% CI 12-18 months), which was longer than the cTACE group [median PFS 11 months (95% CI 10-12 months)]. Median overall survival (OS) was also longer with DEB-TACE [25 months (95% CI 22-28 months)] when compared with cTACE [21 months (95% CI 18-24 months)]. Univariate and multivariate logistic regression analysis showed that DEB-TACE was an independent predictive factor for achieving CR. Univariate Cox's regression analysis revealed that DEB-TACE was a predictive factor for prolonged PFS and OS, while multivariate analysis demonstrated that DEB-TACE was not an independent factor for predicting PFS or OS. In conclusion, we found that DEB-TACE achieved higher treatment response and prolonged survival compared with cTACE in Chinese HCC patients.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Quimioembolização Terapêutica , Neoplasias Hepáticas/tratamento farmacológico , Microesferas , Idoso , China , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento
13.
Phys Chem Chem Phys ; 18(27): 18112-8, 2016 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-27327514

RESUMO

Organolead halide perovskites exhibit superior photoelectric properties, which have given rise to the perovskite-based solar cells whose power conversion efficiency has rapidly reached above 20% in the past few years. However, perovskite-based solar cells have also encountered problems such as current-voltage hysteresis and degradation under practical working conditions. Yet investigations into the intrinsic chemical nature of the perovskite material and its role on the performance of the solar cells are relatively rare. In this work, Raman spectroscopy is employed together with CASTEP calculations to investigate the organic-inorganic interactions in CH3NH3PbI3 and CH3NH3PbBr3-xClx perovskite single crystals with comparison to those having ammonic acid as the cations. For Raman measurements of CH3NH3PbI3, a low energy line of 1030 nm is used to avoid excitation of strong photoluminescence of CH3NH3PbI3. Raman spectra covering a wide range of wavenumbers are obtained, and the restricted rotation modes of CH3-NH3(+) embedded in CH3NH3PbBr3 (325 cm(-1)) are overwhelmingly stronger over the other vibrational bands of the cations. However, the band intensity diminishes dramatically in CH3NH3PbBr3-xClx and most of the bands shift towards high frequency, indicating the interaction with the halides. The details of such an interaction are further revealed by inspecting the band shift of the restricted rotation mode as well as the C-N, NH3(+) and CH3 stretching of the CH3NH3(+) as a function of Cl composition and length of the cationic ammonic acids. The results show that the CH3NH3(+) interacts with the PbX3(-) octahedral framework via the NH3(+) end through N(+)-HX hydrogen bonding whose strength can be tuned by the composition of halides but is insensitive to the size of the organic cations. Moreover, an increase of the Cl content strengthens the hydrogen bonding and thus blueshifts the C-N stretching bands. This is due to the fact that Cl is more electronegative than Br and an increase of the Cl content decreases the lattice constant of the perovskite. The findings of the present work are valuable in understanding the role of cations and halides in the performance of MAPbX3-based perovskite solar cells.

14.
J Biomed Opt ; 19(12): 120503, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25535975

RESUMO

Supercontinuum (SC) source is a new kind of artificial light source, having the characteristics of both laser and traditional incoherent light source, i.e., high brightness, good direction, and super broadband spectrum. The rapid development of SC source stimulates our concern on its ocular damage potency. However, the damage effects of SC source have never been explored. The retinal damage threshold of chinchilla grey rabbit induced by a Vis-infrared SC source was determined for the first time. Additionally, a theoretical method was also developed for analyzing the hazard risks of SC source.


Assuntos
Traumatismos Oculares/patologia , Raios Infravermelhos/efeitos adversos , Lasers/efeitos adversos , Lesões Experimentais por Radiação/patologia , Animais , Coelhos , Retina/lesões , Retina/patologia , Retina/efeitos da radiação
15.
Fitoterapia ; 85: 109-13, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23333907

RESUMO

Danshen is one of the most famous herbs in the world, and more and more danshen-prescribed drugs interactions have been reported in recent years. Evaluation of inhibition potential of danshen's major ingredients towards UDP-glucuronosyltransferases (UGTs) will be helpful for understanding detailed mechanisms for danshen-drugs interaction. Therefore, the aim of the present study is to investigate the inhibitory situation of cryptotanshinone and dihydrotanshinone I towards UGT enzyme-catalyzed propofol glucuronidation. In vitro the human liver microsome (HLM) incubation system was used, and the results showed that cryptotanshinone and dihydrotanshinone I exhibited dose-dependent inhibition towards HLM-catalyzed propofol glucuronidation. Dixon plot and Lineweaver-Burk plot showed that the inhibition type was best fit to competitive inhibition type for both cryptotanshinone and dihydrotanshinone I. The second plot using the slopes from the Lineweaver-Burk plot versus the concentrations of cryptotanshinone or dihydrotanshinone I was employed to calculate the inhibition parameters (Ki) to be 0.4 and 1.7µM, respectively. Using the reported maximum plasma concentration (Cmax), the altered in vivo exposure of propofol increased by 10% and 8.2% for the co-administration of dihydrotanshinone I and cryptotanshinone, respectively. All these results indicated the possible danshen-propofol interaction due to the inhibition of dihydrotanshinone I and cryptotanshinone towards the glucuronidation reaction of propofol.


Assuntos
Anestésicos Intravenosos/metabolismo , Glucuronosiltransferase/antagonistas & inibidores , Interações Ervas-Drogas , Fenantrenos/farmacologia , Propofol/metabolismo , Furanos , Glucuronosiltransferase/metabolismo , Humanos , Microssomos Hepáticos , Plantas Medicinais/química , Quinonas , Salvia miltiorrhiza/química
16.
Chin Med J (Engl) ; 124(20): 3341-6, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22088532

RESUMO

BACKGROUND: Glucose regulated protein 78 (GRP78), an endoplasmic reticulum (ER) chaperone, plays a critical role in chemotherapy resistance in a variety of cancers. In this study, we investigated the up-regulation of GRP78 induced by A23187 and its association with the chemotherapeutical sensibility to cisplatin in human lung cancer cell line SPCA1. METHODS: SPCA1 cells were pretreated with A23187 at different concentrations. The expression of GRP78 at the mRNA level was analyzed by RT-PCR; the expression of GRP78 at the protein level was determined by Western blotting and immunofluorescence assay. Cell survival was determined by MTT assay. Cell apoptosis was analyzed by flow cytometry. RESULTS: The expression of GRP78 at both the mRNA and protein levels was obviously induced by A23187 in SPCA1 cells, with an elevation of GRP78 by 2.1-fold at the mRNA level and by 3.8-fold at the protein level compared to the control. There was a dose-dependent response. Survival curve analysis demonstrated that A23187 induction caused a significant reduction of survival for the cells subjected to cisplatin treatment (P < 0.05). After treatment by cisplatin, the percentage of apoptotic cells in the A23187 pretreated group increased about three fold compared with the control group ((27.53 ± 4.32)% vs. (9.25 ± 3.64)%, P < 0.05). CONCLUSIONS: A23187 treatment was fairly effective for the induction of GRP78 in SPCA1 cells at both the mRNA and protein levels. To a certain extent, GRP78 up-regulation by A23187 was associated with the enhancement of drug sensitivity to cisplatin in human lung cancer cell line SPCA1.


Assuntos
Antineoplásicos/farmacologia , Calcimicina/farmacologia , Cisplatino/farmacologia , Proteínas de Choque Térmico/metabolismo , Apoptose/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , Chaperona BiP do Retículo Endoplasmático , Citometria de Fluxo , Proteínas de Choque Térmico/genética , Humanos , Neoplasias Pulmonares/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
J Org Chem ; 75(15): 5340-2, 2010 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-20578763

RESUMO

A catalyst composed of Pd and hydroxyterphenylphosphine was found to be effective for one-pot benzo[b]furan synthesis from 2-chlorophenols and alkynes.


Assuntos
Benzofuranos/síntese química , Clorofenóis/química , Paládio/química , Catálise , Espectroscopia de Ressonância Magnética
18.
Org Lett ; 11(3): 741-4, 2009 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-19175353

RESUMO

High preference of substitution at the position ortho to the hydroxy group was observed for Ni-catalyzed cross-coupling reactions of dihalophenols with alkyl Grignard reagents. Reactions of 2,4-dihalophenols, with various combinations of F, Cl, and Br, were shown to afford ortho-cross-coupled products selectively. In addition, high ortho preference was also observed in competitive cross-coupling reactions between 2-halophenols and other halophenols.

19.
Zhonghua Xin Xue Guan Bing Za Zhi ; 35(10): 889-92, 2007 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-18206032

RESUMO

OBJECTIVE: To observe the relationship between coronary and carotid/cerebral atherosclerotic stenosis. METHODS: Carotid/aortocranial angiography and coronary angiography were performed in 34 CAD patients complicated with symptomatic cerebral ischemia. Patients were divided into 3 subgroups according to the extent of arterial stenosis determined by angiography. There were 5 light, 4 moderate and 25 severe stenosis determined by coronary angiography and there were 6 light, 6 moderate and 24 severe stenosis determined by carotid/aortocranial angiography. RESULTS: The extent of coronary artery stenosis was parallel to the carotid artery or vertebral artery stenosis. Twenty-four patients out of 25 patients with severe coronary stenosis had severe cerebrovascular stenosis (P = 0.873). The coincident rate was as high as 92% for patients with moderate or severe cerebrovascular stenosis whose Califf risk scores of coronary artery were more than or equal to 2. The follow-up study showed the incidence of cardiovascular event and cerebrovascular event increased significantly in the patients with moderate to severe coronary and cerebral arteries stenosis and 3 patients with severe stenosis found in both coronary and cerebral arteries died during follow up. CONCLUSION: The incidence and severity of coronary artery stenosis is parallel with carotid artery or vertebral artery stenosis.


Assuntos
Aterosclerose/complicações , Arteriosclerose Intracraniana/complicações , Idoso , Aterosclerose/diagnóstico por imagem , Angiografia Cerebral , Angiografia Coronária , Estenose Coronária/complicações , Estenose Coronária/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Arteriosclerose Intracraniana/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade
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