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1.
Pharm Biol ; 62(1): 472-479, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38769628

RESUMO

CONTEXT: The Xihuang pill (XHP) is a traditional Chinese medicine formulation that has been historically used in the prevention and treatment of proliferative breast diseases. However, there is a lack of guidelines that offer recommendations for its clinical use. OBJECTIVE: The task force from the Chinese Guangdong Pharmaceutical Association aims to develop evidence-based guidelines for XHP to prevent and treat proliferative breast diseases. METHODS: We searched six Chinese and English electronic databases, including the China National Knowledge Infrastructure, the Chinese Scientific Journal Database, the Wanfang Medical Database, PubMed, and Embase, up to November 1, 2022. Publications (case reports, clinical observation, clinical trials, reviews) on using XHP to treat proliferative breast diseases were manually searched. The search terms were Xihuang pill, hyperplasia of the mammary gland, breast lump, and mastalgia. The writing team developed recommendations based on the best available evidence. RESULTS: Treatment should be customized based on syndrome identification. We recommend using XHP for the prevention and treatment of breast hyperplasia disease when a patient presents the following syndromes: concurrent blood stasis syndrome, concurrent phlegm-stasis syndrome, and concurrent liver fire syndrome. Safety indicators, including blood analysis and liver and kidney function monitoring, should be performed regularly during treatment. CONCLUSIONS: Current clinical evidence suggests that XHP can be used as a standalone treatment or in conjunction with other medications to prevent and manage breast hyperplasia diseases. More randomized controlled studies are warranted to establish high-quality evidence of its use.


Assuntos
Doenças Mamárias , Medicamentos de Ervas Chinesas , Hiperplasia , Medicina Tradicional Chinesa , Humanos , Feminino , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/administração & dosagem , Doenças Mamárias/tratamento farmacológico , Medicina Tradicional Chinesa/métodos , China
2.
Plant Cell Rep ; 42(11): 1757-1776, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37674059

RESUMO

KEY MESSAGE: The novel interkingdom PGPM consortia enhanced the ability of plant growth promotion and disease resistance, which would be beneficial to improve plant growth in sustainable agriculture through engineering microbiome. Plant growth-promoting microbes (PGPMs) play important roles in promoting plant growth and bio-controlling of pathogens. Much information reveals that the plant growth-promoting ability of individual PGPM affects plant growth. However, the effects of the PGPM consortia properties on plant growth remain largely unexplored. Here, we characterized three new PGPM strains including Rhodotorula graminis JJ10.1 (termed as J), Pseudomonas psychrotolerans YY7 (termed as Y) and P. chlororaphis T8 (termed as T), and assessed their effects in combination with Bacillus amyloliquefaciens FZB42 (termed as F) on plant growth promotion and disease prevention in Arabidopsis thaliana and tomato (Solanum lycopersicum) plants by investigating morphological changes, whole-genome sequencing and plant growth promoting (PGP) characterization. Results revealed that the three new strains R. graminis JJ10.1, P. psychrotolerans YY7 and P. chlororaphis T8 had the potential for being combined with B. amyloliquefaciens FZB42 to form interkingdom PGPM consortia. The combinations of R. graminis JJ10.1, B. amyloliquefaciens FZB42, and P. psychrotolerans YY7, i. e. JF and JYF, exhibited the strongest ability of synergetic biofilm production. Furthermore, the growth-promotion abilities of the consortia were significantly enhanced compared with those of individual strains under both inoculation and volatile organic compounds (VOCs) treatment. Importantly, the consortia showed stronger abilities of in planta disease prevention than individual strains. Findings of our study may provide future guidance for engineering the minimal microbiome communities to improve plant growth and/or disease resistance in sustainable agriculture.


Assuntos
Arabidopsis , Solanum lycopersicum , Resistência à Doença , Desenvolvimento Vegetal
3.
Ann Hepatol ; 28(1): 100775, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36280014

RESUMO

INTRODUCTION AND OBJECTIVES: Liver fibrosis is a common pathological change in many chronic liver diseases. Activation of hepatic stellate cells (HSCs) is the core event in liver fibrosis. This study aimed to investigate the role of testicular orphan receptor 4 (TR4) in the activation of HSCs. MATERIALS AND METHODS: In vivo, bile duct ligation (BDL)-induced rat liver fibrosis model was established, and the expressions of TR4 and α-smooth muscle actin (α-SMA) in liver tissues were detected. In vitro, TR4 knockdown and overexpression in JS-1 cells using lentiviral vectors were constructed, and the expressions of TR4, α-SMA, Col-I, and TGF-ß1/smads and retinoid X receptor (RXR) pathway-related genes were detected. RESULTS: TR4 was highly expressed in BDL-induced fibrotic liver, accompanied by increased expression of α-SMA. Knockdown of TR4 significantly inhibited the expressions of α-SMA, Col-I, p-TßRI, and p-Smad2/3, and up-regulated the expression of RXRα in HSCs in vitro. In contrast, TR4 overexpression significantly increased the expressions of α-SMA, Col-I, p-TßRI, and p-Smad2/3, and inhibited the expression of RXRα. CONCLUSIONS: TR4 may promote the activation of HSCs by up-regulating TßR I/Smad2/3 signaling pathway and down-regulating RXRα signaling, thereby promoting the progression of liver fibrosis. Our findings may provide a new therapeutic target against hepatic fibrosis.


Assuntos
Células Estreladas do Fígado , Fator de Crescimento Transformador beta1 , Ratos , Animais , Células Estreladas do Fígado/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Cirrose Hepática/metabolismo , Transdução de Sinais , Fígado/patologia , Receptores de Fatores de Crescimento Transformadores beta/metabolismo
4.
Plant Dis ; 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37874282

RESUMO

Chinese dwarf cherry (Cerasus humilis) is a perennial small shrub indigenous to northern China, highly regarded for its calcium-rich fruit known as 'calcium fruit'. These fruits have a remarkable capacity to aid in human calcium absorption. Additionally, they contain beneficial flavonoids that hold promise for applications in the healthcare industry (Wang et al., 2018). In July 2020, a concerning development occurred on the farms in Jingtai County (37.48o N, 103.82o E), Baiyin City, Gansu Province in China. Approximately 20 to 30% of C. humilis at the full culture stage exhibited symptoms of root rot, including brownish leaves, rotten roots, and plant mortality, leading to a decrease of over 30% in calcium fruit yield. To identify the pathogen, the surface of symptomatic roots was sterilized with 3% NaOCl for 2 minutes, followed by 70% ethanol for 30 seconds, and rinsed three times with sterile water. Tissue sections (5×5mm) from the margin of the necrotic lesion were cut and cultured on potato dextrose agar (PDA) medium, and incubated for 7 days at 25℃. Five pure culture isolates were obtained from individual spores. Initially, the isolates exhibited abundant white aerial mycelia that turned light pink on the third day. Macroconidia were falciform, two to five septate, straight or slightly curved, and measuring 20.1 to 32.5×2.2 to 3.8 µm (n=50). Napiform microconidia were oval-ellipsoid, non-septate, and measuring 6.2 to 9.3×4.2 to 5.8 µm (n=50). Based on these morphological characteristics, the fungus was tentatively identified as Fusarium species (Leslie and Summerell, 2006). To confirm the identification, the internal transcribed spacer region (ITS) and the translation elongation factor (EF1α) of the isolate CH-2 were partially amplified and sequenced using the primers ITS1/ITS4 and EF2T/EF3 (Li et al., 2013, Yang et al., 2022). Upon comparison with the sequences in GenBank, 857 bp ITS sequence showed 100% homology to Fusarium tricinctum isolate QY3-1 (GenBank accessions no. MZ572963.1), and 665 bp EF1α sequence showed 99.7% homology to F. tricinctum strain TQC-C2 (GenBank accessions no. KF939493.1). The resulting sequences were deposited into GenBank with accession nos. OQ581576 and OQ848462 respectively. A maximum likelihood (ML) phylogenetic analysis based on combined partial ITS and EF1α data set was conducted via ML bootstrapping using MEGA 11. According to morphology and phylogenetic analysis, the isolate was identified as F. tricinctum (Wang et al., 2022). For a pathogenicity test, a pot experiment was conducted in a greenhouse with a temperature range of 20-27℃ and 60% relative humidity. Roots of C. humilis were immersed in a spore suspension (1×107 conidia/ml) of isolate F. tricinctum CH-2 for approximately 5 minutes. Subsequently the treated roots were planted in pots filled with sterilized field soil, while roots dipped in sterilized water were used as the control. The experiment considered of ten pots for the inoculation treatment and six pots for the control treatment. All pots were maintained in the greenhouse. After 15 days, it was observed that 80% of the inoculated plants displayed symptoms consistent with the field observations, indicating successful infection. In contrast, plants in the control treatment did not exhibit any symptoms. The same fungal pathogen as F. tricinctum CH-2 was reisolated from the diseased root tissue and confirmed through morphological and molecular assays, thereby satisfying Koch's postulates. This is the first documented report of F. tricinctum causing root rot in C. humilis in China. This disease has the potential to become one of the most significant diseases affecting C. humilis in China.

5.
Plant Dis ; 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37392030

RESUMO

Celery (Apium graveolens L.) is an economically important vegetable crop in China. In recent years, celery has been widely planted in Yuzhong county, Gansu province. From 11 April to 24 May, 2019-2021, basal stem rot of celery was observed with incidences up to 15% in the Yuzhong region (35°49'N, 104°16'E, 1865 m a.s.l.), which caused serious economic losses to local farmers. Typical symptoms of the disease included wilting and darkening of the basal stem, leading to plant death. To identify the cause of the disease, small pieces (5mm×5mm) of the margin of asymptomatic and rotting basal stem tissues were sterilized with 70% ethanol for 30 s and 3% NaClO for 5 min, then placed on potato dextrose agar (PDA) plates, and incubated at 25℃ (Zhao et al. 2021). Twenty-seven single-conidium isolates with morphological characteristics similar to Fusarium spp. were obtained (Ma et al. 2022), which displayed two kinds of colony morphology. On PDA, seven isolates developed white, fluffy aerial mycelium and twenty isolates developed light pink abundant aerial mycelium. Isolate F5 and F55 from each distinct morphological group were cultured on PDA and synthetic low nutrient agar (SNA) for pathogenicity tests, morphological and molecular identification. The macroconidia (18.3 to 29.6 × 3.6 to 5.3 µm, n=50) with 1 to 2 septa and microconidia (7.5 to 11.6 × 2.6 to 3.5 µm, n=50) with 0 to 1 septum were observed in F5. For F55, the size of macroconidia was 14.2 to 19.5 × 3.3 to 4.2 µm (n = 50) with 1 to 2 septa; Microconidia were mostly 0 to 1 septum and measured 7.3 to 12.8 × 2.2 to 4.2 µm (n = 50). To confirm the identity of the isolates, the internal transcribed spacer region (ITS) and the translation elongation factor-1 alpha (TEF-1α) gene were amplified using primers ITS1/ITS4 and EF-1/EF-2 (Uwaremwe et al. 2020), respectively. The sequence similarities of isolate F5 (GenBank No. OL616048 and OP186480) and F55 (GenBank No. OL616049 and OP186481) with the corresponding sequences of F. solani (MT447508 and MN650097) and F. oxysporum (MG461555 and OQ632904) ranged from 99.22% to 100.00%, with matching base pairs of 531/532, 416/416, 511/515 and 394/395, respectively. The voucher samples were deposited in the sample center of Northwest Institute of Ecological Environment and Resources, Chinese Academy of Sciences. Morphological and molecular results confirmed the species of F5 and F55 as F. solani and F. oxysporum, respectively. A pathogenicity test was conducted under greenhouse conditions (19-31°C, avg. 26°C). Conidial suspension (105 spores/mL) of isolates F5 and F55 were poured onto the basal stems of healthy celery seedlings at the age of 1 month and mock-inoculated control treatments with sterile water. Ten plants were inoculated for each treatment. After 21 days, all plants inoculated with both fungal isolates developed symptoms similar to those observed in the field, whereas the mock-inoculated plants remained healthy. The pathogen was successfully reisolated from the inoculated symptomatic plants onto PDA medium and had morphology as described above, confirming Koch's postulates. F. solani and F. oxysporum have been reported to infect many plant species, including carrot (Zhang et al. 2014) and Angelica sinensis (Liu et al. 2022). To our knowledge, this is the first report that F. solani and F. oxysporum cause basal stem rot on celery in China. The identification of pathogens of the observed basal stem rot on celery provides a clear target for the prevention and management of this disease.

6.
Angew Chem Int Ed Engl ; 62(13): e202218717, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36728627

RESUMO

The aqueous electrocatalytic reduction of NO3 - into NH3 (NitrRR) presents a sustainable route applicable to NH3 production and potentially energy storage. However, the NitrRR involves a directly eight-electron transfer process generally required a large overpotential (<-0.2 V versus reversible hydrogen electrode (vs. RHE)) to reach optimal efficiency. Here, inspired by biological nitrate respiration, the NitrRR was separated into two stages along a [2+6]-electron pathway to alleviate the kinetic barrier. The system employed a Cu nanowire catalyst produces NO2 - and NH3 with current efficiencies of 91.5 % and 100 %, respectively at lower overpotentials (>+0.1 vs. RHE). The high efficiency for such a reduction process was further explored in a zinc-nitrate battery. This battery could be specified by a high output voltage of 0.70 V, an average energy density of 566.7 Wh L-1 at 10 mA cm-2 and a power density of 14.1 mW cm-2 , which is well beyond all previously reported similar concepts.

7.
Angew Chem Int Ed Engl ; 62(30): e202305695, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37235524

RESUMO

Redox flow batteries have been discussed as scalable and simple stationary energy storage devices. However, currently developed systems encounter less competitive energy density and high costs, restricting their wider application. There is a lack of appropriate redox chemistry, preferably based on active materials that are abundant in nature and show high solubility in aqueous electrolytes. A nitrogen-centered redox cycle operating between the limiting species ammonia and nitrate via an eight-electron redox reaction stayed practically unnoticed, albeit its ubiquity in biological processes. Ammonia or nitrate are world-scale chemicals with high aqueous solubility, and are then comparably safe. We demonstrate here the successful implementation of such a nitrogen-based redox cycle between ammonia and nitrate with eight-electron transfer as a catholyte for Zn-based flow batteries, which continuously worked for 12.9 days with 930 charging-discharging cycles. A very competitive energy density of 577 Wh L-1 can be reached, which is well above most reported flow batteries (e.g. 8 times the standard Zn-bromide battery), demonstrating that the nitrogen cycle with eight-electron transfer can offer promising cathodic redox chemistry for safe, affordable, and scalable high-energy-density storage devices.

8.
Angew Chem Int Ed Engl ; 61(27): e202203170, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35478427

RESUMO

Direct synthesis of N-containing organic compounds from dinitrogen (N2 ) can make synthetic chemistry more sustainable. Previous bottlenecks in lithium-mediated N2 fixation were resolved by loading Li-metal anodes covered with the typical Li+ ion-conducting solid electrolyte interface, which are subsequently allowed to react with N2 . The developed strategy allowed us to reach high Faradaic efficiencies toward Li3 N. These reactive Li3 N were then contacted with acylchlorides. Surface nitride ions are more nucleophilic than amines which direct the two C-N coupling reactions toward formation of imides rather than amides, and an integrated current efficiency of 57-77 % could be realized. This study thereby not only provides a feasible electrochemical Li3 N synthesis, but also delineates an economical and green synthesis of highly valuable N-containing compounds from N2 under mild conditions, just using commercial spare parts and processes from the omnipresent Li battery technology.

9.
Pharm Biol ; 59(1): 1150-1160, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34425061

RESUMO

CONTEXT: Our previous studies indicated that Yiguanjian decoction (YGJ) has an anti-hepatic-fibrosis effect and could regulate macrophage status. OBJECTIVE: To elucidate the mechanism of YGJ in regulating macrophages. MATERIALS AND METHODS: Liver cirrhosis was induced by CCl4 for 12 weeks combined with 2-acetylaminofluorene (2-AAF) for the last 4 weeks in male Wistar rats. YGJ (3.56 mg/kg) orally administered in the last 4 weeks, and SORA (1 mg/kg) as control. In vitro, RAW264.7 cells were treated with lipopolysaccharides (LPSs) to induce macrophage polarization to the M1 phenotype, and they were co-cultured with WB-F344 cells and allocated to M group, YGJ group (2 µg/mL) and WIF-1 group (1 µg/mL) with untreated cells as control. The differentiation direction of WB-F344 cell line was observed in the presence or absence of YGJ. Pathology, fibrosis-related cytokines, macrophage polarization-related components, and Wnt signalling pathway components were detected. RESULTS: In vivo, the expression levels of α-SMA, Col (1), OV6, SOX9, EpCAM and M1 macrophage-related components (STAT1, IRF3, IRF5, IRF8, SOCS3) significantly decreased in the YGJ group compared with those in the 2-AAF/CCl4 group (p < 0.01 or 0.05). In vitro, the expression levels of M1 macrophage-related components, including STAT1, NF-κB, IRF3, IRF5, and SOCS3, in RAW264.7 cells decreased significantly in the YGJ group compared with those in the M group (p < 0.05 or p < 0.01). The expression levels of Wnt3A, FZD5, LRP-5/-6, and ß-catenin significantly increased in the YGJ group compared with those in the M group (p < 0.05 or p < 0.01). In addition, the expression levels of Wnt-4/-5A/-5B, and FZD2 significantly decreased in the YGJ group compared with those in the M group (p < 0.05 or p < 0.01). CONCLUSION: This study suggests that the anti-cirrhosis effect of YGJ is associated with its ability to inhibit macrophage M1-polarization, which provides a scientific basis for the clinical application of YGJ.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Cirrose Hepática Experimental/tratamento farmacológico , Macrófagos/efeitos dos fármacos , 2-Acetilaminofluoreno , Animais , Tetracloreto de Carbono , Linhagem Celular , Citocinas/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Células RAW 264.7 , Ratos , Ratos Endogâmicos F344 , Ratos Wistar , Via de Sinalização Wnt/efeitos dos fármacos
10.
Pharm Biol ; 58(1): 1229-1243, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33332219

RESUMO

CONTEXT: Xiayuxue decoction (XYXD), a traditional Chinese medicine, is used for treating liver disease. However, the potential active constituents and mechanisms are still unclear. OBJECTIVE: To explore the main active fraction extracts, active ingredients and possible mechanisms of XYXD for anti-hepatic fibrosis. MATERIALS AND METHODS: Different fractions including ethyl acetate fraction (EF) were prepared from XYXD. These fractions, especially EF, were used to evaluate cell viability, proliferation, cell cycle, cytotoxicity and activation in hepatic stellate cells (HSCs). Liver fibrosis model was established by CCl4 in C57BL/6 mice, and allocated to CCl4 group, XYXD group and EF group with normal mice as control. Further, mitochondrial apoptosis-related proteins of HSCs, destruction and angiogenesis of liver sinusoidal endothelial cells (LSECs) and active ingredients of EF were evaluated. RESULTS: The inhibition of proliferation, increase of S or/and G2/M phase population and suppression of α-SMA and COL-1 expression were obeserved in EF treated-JS1 and -LX2. Liver fibrosis-related indicators were improved by EF similar to XYXD in vivo. EF induced the apoptosis of HSCs in CCl4-induced fibrosis, and inhibited the expression of HSCs apoptosis pathway-related proteins (JNK and p38-MAPKs), and LSECs destruction and angiogenesis. Multiple ingredients (emodin, rhein, aloe-emodin, prunasin) in EF have shown inhibited the activation of JS1. DISCUSSION AND CONCLUSION: EF was the main active fraction extracts of XYXD, and the underlying mechanisms might relate to induction of HSCs apoptosis. Emodin, rhein, aloe-emodin and prunasin were main active ingredients of EF, which provides a potential drug for the treatment of liver fibrosis.


Assuntos
Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática/tratamento farmacológico , Fígado/efeitos dos fármacos , Animais , Tetracloreto de Carbono , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/uso terapêutico , Cirrose Hepática/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Medicina Tradicional Chinesa , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley
11.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(6): 1031-1036, 2020 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-33369342

RESUMO

To investigate the computed tomography (CT) characteristics and differential diagnosis of high altitude pulmonary edema (HAPE) and COVID-19, CT findings of 52 cases of HAPE confirmed in Medical Station of Sanshili Barracks, PLA 950 Hospital from May 1, 2020 to May 30, 2020 were collected retrospectively. The size, number, location, distribution, density and morphology of the pulmonary lesions of these CT data were analyzed and compared with some already existed COVID-19 CT images which come from two files, "Radiological diagnosis of COVID-19: expert recommendation from the Chinese Society of Radiology (First edition)" and "A rapid advice guideline for the diagnosis and treatment of 2019 novel corona-virus (2019-nCoV) infected pneumonia (standard version)". The simple or multiple ground-glass opacity (GGO) lesions are located both in the HAPE and COVID-19 at the early stage, but only the thickening of interlobular septa, called "crazy paving pattern" belongs to COVID-19. At the next period, some increased cloudy shadows are located in HAPE, while lesions of COVID-19 are more likely to develop parallel to the direction of the pleura, and some of the lesions show the bronchial inflation. At the most serious stage, both the shadows in HAPE and COVID-19 become white, but the lesions of HAPE in the right lung are more serious than that of left lung. In summary, some cloudy shadows are the feature of HAPE CT image, and "crazy paving pattern" and "pleural parallel sign" belong to the COVID-19 CT, which can be used for differential diagnosis.


Assuntos
Altitude , COVID-19/diagnóstico por imagem , Edema Pulmonar/diagnóstico por imagem , China , Diagnóstico Diferencial , Humanos , Pulmão/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
12.
Chemistry ; 25(54): 12464-12485, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31120594

RESUMO

The electrochemical reduction of nitrogen into ammonia under ambient conditions is a potential strategy for sustainable ammonia production. At present, one of the main research directions in the field of electrochemical nitrogen fixation is to improve the current efficiency and ammonia yield by developing efficient nitrogen reduction catalysts. To optimise the selectivity and catalytic activity of nitrogen reduction catalysts more efficiently, herein, we systematically summarise the progress of research on nitrogen reduction catalysts in recent years and present some general catalyst design strategies. Considering that it is difficult for metal-based catalysts to balance the competitive reactions of nitrogen activation and hydrogen evolution, we discuss in detail the advantages and application prospects of non-metallic catalysts in electrochemical nitrogen fixation. Moreover, both the design strategy of surface or interface defects, and how this atomic-level control of functionalisation helps to promote selectivity and catalytic activity are also discussed by theoretical and experimental electrochemistry. On this basis, we also discussed the future development direction, opportunities and challenges of nitrogen reduction electrocatalysts.

13.
Angew Chem Int Ed Engl ; 58(9): 2612-2616, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30560583

RESUMO

Constructing efficient catalysts for the N2 reduction reaction (NRR) is a major challenge for artificial nitrogen fixation under ambient conditions. Herein, inspired by the principle of "like dissolves like", it is demonstrated that a member of the nitrogen family, well-exfoliated few-layer black phosphorus nanosheets (FL-BP NSs), can be used as an efficient nonmetallic catalyst for electrochemical nitrogen reduction. The catalyst can achieve a high ammonia yield of 31.37 µg h-1 mg-1 cat. under ambient conditions. Density functional theory calculations reveal that the active orbital and electrons of zigzag and diff-zigzag type edges of FL-BP NSs enable selective electrocatalysis of N2 to NH3 via an alternating hydrogenation pathway. This work proves the feasibility of using a nonmetallic simple substance as a nitrogen-fixing catalyst and thus opening a new avenue towards the development of more efficient metal-free catalysts.

14.
Toxicol Appl Pharmacol ; 342: 69-78, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29407775

RESUMO

The aim of this study was to determine the effect of ursodeoxycholic acid (UDCA) on the alpha-naphthylisothiocyanate (ANIT)-induced acute and recovery stage of cholestasis model mice. In the acute stage of model mice, pretreatment with UDCA (25, 50, and 100 mg·kg-1, ig) for 12 days prior to ANIT administration (50 mg·kg-1, ig) resulted in the dramatic increase in serum biochemistry, with aggrevation of bile infarcts and hepatocyte necrosis. The elevation of beta-muricholic acid (ß-MCA), cholic acid (CA), and taurocholic acid (TCA) in serum and liver, and reduction of these bile acids (BAs) in bile was observed. In contrast, in the recovery stage of model mice, treatment with UDCA (25, 50, and 100 mg·kg-1, ig) for 7 days after ANIT administration (50 mg·kg-1, ig) resulted in the significant decrease in levels of serum alanine aminotransferase (ALT) and total bile acid (TBA). Liver injury was attenuated, and the levels of TBA, CA, TCA, and ß-MCA in the liver were significantly decreased. Additionally, UDCA can upregulate expression of BSEP, but it cannot upregulate expression of AE2. UDCA, which induced BSEP to increase bile acid-dependent bile flow, aggravated cholestasis and liver injury when the bile duct was obstructed in the acute stage of injury in model mice. In contrast, UDCA alleviated cholestasis and liver injury induced by ANIT when the obstruction was improved in the recovery stage.


Assuntos
1-Naftilisotiocianato/toxicidade , Colestase Intra-Hepática/induzido quimicamente , Colestase Intra-Hepática/tratamento farmacológico , Recuperação de Função Fisiológica/efeitos dos fármacos , Ácido Ursodesoxicólico/toxicidade , Ácido Ursodesoxicólico/uso terapêutico , Doença Aguda , Animais , Colestase Intra-Hepática/patologia , Camundongos , Camundongos Endogâmicos C57BL , Recuperação de Função Fisiológica/fisiologia
15.
Zhongguo Zhong Yao Za Zhi ; 43(19): 3905-3912, 2018 Oct.
Artigo em Zh | MEDLINE | ID: mdl-30453717

RESUMO

The aim of this paper was to observe the function of bone marrow mesenchymal stem cell (BMSC) transplantation in process of liver injury induced by carbon tetrachloride (CCl4) in vivo and the intervention effect of Yiguanjian (YGJ), a compound of Chinese herbal medicine. Wistar rats were randomly divided into five groups: normal group, model group, cell transplantation (CT) group, YGJ group and cell transplantation plus Yiguanjian (CTY) group. Liver injury was induced through subcutaneous injection with CCl4 at a dose of 3 mL·kg⁻¹ body weight for 4 weeks, twice a week. They were injected for a total of 9 times. After the first injection with CCl4, rats in the CT group and CTY group were injected with the third-generation BMSCs at dose 1×106 (suspended in 1 mL saline solution) via tail vein. Rats in the YGJ and CTY groups were also intragastrically administered with Yiguanjian once a day. Rat serum ALT and AST activities were increased significantly on the second day after injection with CCl4, while BMSC transplantation and Yiguanjian decreased their activities. After 4 weeks of injection with CCl4, serum ALT, AST and γ-GT activities, and serum TNF-α and IL-6 expressions were increased, while TBIL were decreased in model rats compared with normal rats. Meanwhile, liver cells edema, plasmatic loose, and numerous lipid droplets were observed in rats of the model group. BMSC transplantation aggravated liver injury compared with model rats, which was manifested by decreasing SOD activity, increased MDA, TG, TNF-α and IL-6 levels, and aggravated necrosis level of hepatocytes, fusion of lipid droplets, and collagen deposition in liver tissue. Yiguanjian decreased liver injury induced by CCl4 alone and CCl4 plus BMSC transplantation. SRY gene in situ hybridization method was used to detect the positive SRY expressions in heart, liver, spleen, lung and kidney, especially in liver, while Yiguangjian decreased liver SRY expression. Wnt and ß-catenin showed high expressions in rats of normal group, which were decreased significantly in rats of models group, while Yiguanjian increased their expressions. In conclusion, BMSC transplantation could exacerbate liver injury, while Yiguanjian could protect liver injury induced by CCl4 and BMSC transplantation, which was related to decreasing the homing of BMSCs to liver and up-regulating Wnt/ß-catenin signaling pathway.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/terapia , Medicamentos de Ervas Chinesas/farmacologia , Cirrose Hepática Experimental/terapia , Transplante de Células-Tronco Mesenquimais , Animais , Medula Óssea , Tetracloreto de Carbono , Fígado , Ratos , Ratos Wistar , Via de Sinalização Wnt
16.
J Am Chem Soc ; 139(29): 9771-9774, 2017 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-28693318

RESUMO

We report the discovery of a dramatically enhanced N2 electroreduction reaction (NRR) selectivity under ambient conditions via the Li+ incorporation into poly(N-ethyl-benzene-1,2,4,5-tetracarboxylic diimide) (PEBCD) as a catalyst. The detailed electrochemical evaluation and density functional theory calculations showed that Li+ association with the O atoms in the PEBCD matrix can retard the HER process and can facilitate the adsorption of N2 to afford a high potential scope for the NRR process to proceed in the "[O-Li+]·N2-Hx" alternating hydrogenation mode. This atomic-scale incorporation strategy provides new insight into the rational design of NRR catalysts with higher selectivity.

17.
Lab Invest ; 96(3): 350-60, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26692291

RESUMO

Although hepatic progenitor cells (HPCs) are known to contribute to cholestatic liver fibrosis (CLF), how Notch signaling modulates the differentiation of HPCs to cholangiocytes in CLF is unknown. Thus, using a rat model of CLF that is induced by bile duct ligation, we inhibited Notch signaling with DAPT. In vivo, CK19, OV6, Sox9, and EpCAM expression was increased significantly. Notch signaling increased after bile duct ligation, and DAPT treatment reduced the expression of CK19, OV6, Sox9, and EpCAM and blocked cholangiocyte proliferation and CLF. In vitro, treatment of a WB-F344 cell line with sodium butyrate resulted in increased mRNA and protein expression of CK19, Sox9, and EpCAM, but Notch signaling was activated. Both of these processes were inhibited by DAPT. This study reveals that Notch signaling activation is required for HPC differentiation into cholangiocytes in CLF, and inhibition of the Notch signaling pathway may offer a therapeutic approach for treating CLF.


Assuntos
Colestase/complicações , Cirrose Hepática/etiologia , Fígado/citologia , Receptores Notch/fisiologia , Transdução de Sinais/fisiologia , Células-Tronco/citologia , Animais , Diferenciação Celular , Cirrose Hepática/prevenção & controle , Ratos , Ratos Sprague-Dawley
18.
Proteome Sci ; 14: 3, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26843850

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a clinical frequent disease. However, its pathogenesis still needs further study, especially the mechanism at the molecular level. The recent identified novel protein post-translational modification, lysine succinylation was reported involved in diverse metabolism and cellular processes. In this study, we performed the quantitative succinylome analysis in the liver of NAFLD model to elucidate the regulatory role of lysine succinylation in NAFLD progression. METHODS: Firstly, experimental model of NAFLD was induced by carbon tetrachloride injection and supplementary high-lipid and low-protein diet. Then series histochemical and biochemical variables were determined. For the quantitative succinylome analysis, tandem mass tags (TMT)-labeling, highly sensitive immune-affinity purification, liquid chromatography-tandem mass spectrometry techniques were applied. Bioinformatics analysis including gene ontology annotation based classification; Wolfpsort based subcellular prediction; function enrichment; protein-protein interaction network construction and conserved succinylation site motifs extraction were performed to decipher the differentially changed succinylated proteins and sites and p-value < 0.05 was selected as threshold. RESULTS: Totally, 815 succinylation sites on 407 proteins were identified, of which 243 succinylation acetylation sites on 178 proteins showed changed succinylation level with the threshold fold change > 1.5. Theses differentially changed succinylated proteins were involved in diverse metabolism pathways and cellular processes including carbon metabolism, amino acid metabolism, fat acid metabolism, binding and catalyzing, anti-oxidation and xenobiotics metabolism. Besides, these differentially changed succinylated proteins were prominently localized to cytoplasm and mitochondria. Moreover, 8 conserved succinylation site motifs were extracted around the succinylation sites. CONCLUSIONS: Protein succinylation was an extensive post-translation modification in rat. The changed succinylation level in diverse proteins may disturb multiple metabolism pathways and promote non-alcoholic fatty liver disease development. This study provided a basis for further characterization of the pathophysiological role of lysine succinylation in NAFLD progression, which laid a foundation for the innovation of novel NAFLD drugs and therapies.

19.
Chemistry ; 21(12): 4614-21, 2015 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-25572117

RESUMO

Three-dimensional (3D) nanometal films serving as current collectors have attracted much interest recently owing to their promising application in high-performance supercapacitors. In the process of the electrochemical reaction, the 3D structure can provide a short diffusion path for fast ion transport, and the highly conductive nanometal may serve as a backbone for facile electron transfer. In this work, a novel polypyrrole (PPy) shell@3D-Ni-core composite is developed to enhance the electrochemical performance of conventional PPy. With the introduction of a Ni metal core, the as-prepared material exhibits a high specific capacitance (726 F g(-1) at a charge/discharge rate of 1 A g(-1)), good rate capability (a decay of 33% in Csp with charge/discharge rates increasing from 1 to 20 A g(-1)), and high cycle stability (only a small decrease of 4.2% in Csp after 1000 cycles at a scan rate of 100 mV s(-1)). Furthermore, an aqueous symmetric supercapacitor device is fabricated by using the as-prepared composite as electrodes; the device demonstrates a high energy density (≈21.2 Wh kg(-1)) and superior long-term cycle ability (only 4.4% and 18.6% loss in Csp after 2000 and 5000 cycles, respectively).

20.
Zhonghua Gan Zang Bing Za Zhi ; 23(2): 107-11, 2015 Feb.
Artigo em Zh | MEDLINE | ID: mdl-25880976

RESUMO

OBJECTIVE: To investigate the methods for assessing angiogenesis in experimental liver fibrosis. METHODS: Male C57BL/6 mice were randomly divided into a normal (unmodeled) group and a liver fibrosis model group.The model was established by a 4-week course of 10% CCl4 solution (in olive oil) intraperitoneal injection. Liver vasculature was observed by magnetic resonance (MR),computed tomography (CT),synchrotron radiation X-ray,and von Willibrand factor(vWF) immunofluorescence staining. Liver inflammation and fibrosis were observed by staining with hematoxylin-eosin and Sirius red.The t-test and Pearson's correlation analysis were used for statistical analyses. RESULTS: Compared with the normal group,the model group had more robust inflammation and fibrosis in liver tissue.The liver tissue in the modeled mice showed significant deceases in MR signal intensity on T2WI before and after enhancement (386.67+/-69.04 vs.492.67+/-112.50,t =-2.456, P=0.026).The liver tissue in the modeled mice also showed significantly decreased enhancement CT values (P < 0.01).Synchrotron radiation X-ray imaging showed that the small vessels in the liver tissues of the modeled mice were significantly increased compared to that in the normal mice (P < 0.01).The MR T2W enhanced signal value (439.67+/-104.80, Pearson's r=0.714, P=0.009) and microvascular relative length (676.53+/-122.75, Pearson's r=0.791, P=0.002) were positive correlated with microvessel density (MVD) (14.50+/-5.95),as shown by detection of labeled vWF.The before and after CT enhancement difference (132.60+/-57.02, Pearson's r=-0.612, P=0.034) was negatively correlated with MVD. CONCLUSION: s MR,CT and synchrotron radiation X-ray imaging can be used for assessing angiogenesis in liver fibrosis,and the findings from each are correlated with the traditional MVD detection method. The two-dimensional imaging of synchrotron radiation X-ray is more intuitive,and has been confirmed as an effective evaluation method for liver angiogenesis.


Assuntos
Cirrose Hepática/patologia , Neovascularização Patológica , Animais , Modelos Animais de Doenças , Inflamação/patologia , Testes de Função Hepática , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Síncrotrons , Tomografia Computadorizada por Raios X
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