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1.
Angew Chem Int Ed Engl ; 63(27): e202320014, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38598078

RESUMO

Amino acids are the building blocks of proteins and are widely used as important ingredients for other nitrogen-containing molecules. Here, we report the sustainable production of amino acids from biomass-derived hydroxy acids with high activity under visible-light irradiation and mild conditions, using atomic ruthenium-promoted cadmium sulfide (Ru1/CdS). On a metal basis, the optimized Ru1/CdS exhibits a maximal alanine formation rate of 26.0 molAla ⋅ gRu -1 ⋅ h-1, which is 1.7 times and more than two orders of magnitude higher than that of its nanoparticle counterpart and the conventional thermocatalytic process, respectively. Integrated spectroscopic analysis and density functional theory calculations attribute the high performance of Ru1/CdS to the facilitated charge separation and O-H bond dissociation of the α-hydroxy group, here of lactic acid. The operando nuclear magnetic resonance further infers a unique "double activation" mechanism of both the CH-OH and CH3-CH-OH structures in lactic acid, which significantly accelerates its photocatalytic amination toward alanine.


Assuntos
Aminoácidos , Biomassa , Compostos de Cádmio , Rutênio , Sulfetos , Sulfetos/química , Rutênio/química , Compostos de Cádmio/química , Catálise , Aminoácidos/química , Processos Fotoquímicos , Teoria da Densidade Funcional , Luz
2.
J Am Chem Soc ; 143(29): 10940-10947, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34281341

RESUMO

Detailed information about the influences of the cooperative motion of water and methanol molecules on practical solid-liquid heterogeneous photocatalysis reactions is critical for our understanding of photocatalytic reactions. The present work addresses this issue by applying operando nuclear magnetic resonance (NMR) spectroscopy, in conjunction with density functional theory (DFT) calculations and ab initio molecular dynamics (AIMD) simulations, to investigate the dynamic behaviors of heterogeneous photocatalytic systems with different molar ratios of water to methanol on rutile-TiO2 photocatalyst. The results demonstrate that methanol and water molecules are involved in the cooperative motions, and the cooperation often takes the form of methanol-water clusters that govern the number of methanol molecules reaching to the active sites of the photocatalyst per unit time, as confirmed by the diffusion coefficients of the methanol molecule calculated in the binary methanol-water solutions. Nuclear Overhauser effect spectroscopy experiments reveal that the clusters are formed by the hydrogen bonding between the -OH groups of CH3OH and H2O. The formation of such methanol-water clusters is likely from an energetic standpoint in low-concentration methanol, which eventually determines the yields of methanol reforming products.

3.
Pharmazie ; 69(1): 43-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24601222

RESUMO

Colchicine (COL), an alkaloid derived from plants, has been used to treat gout, pseudogout and familial Mediterranean fever for several decades. The purpose of this study was to investigate the in vivo effect of COL on rat cytochrome P450 enzymes (CYP1A2, CYP2C9, CYP2C19 and CYP2D6) to assess its potential to interact with co-administered drugs. This was a randomized, double-blind, two-way crossover study with a 4-week washout period between the phases. Rats received COL via an irrigation stomach needle at a dose of 0.4 mg/kg once daily for consecutive 10 days. On the eleventh day, a cocktail solution at a dose of 4 ml/kg, which contained phenacetin (15.0 mg/kg), tolbutamide (3.0 mg/kg), omeprazole (15.0 mg/kg) and dextromethorphan (15.0mg/kg), was oral administered to all rats. Then 0.3 ml blood samples were collected at a set of time-points. The plasma concentrations of probe drugs were simultaneously determined by HPLC-MS/MS. Pharmacokinetic parameters simulated by DAS software were used for the evaluation of COL on the activities of rat CYP1A2, CYP2C9, CYP2C19 and CYP2D6 enzymes. Our study showed that COL administration induced CYP2C9 activity, causing a significant decrease in AUC(0-infinity) (P < 0.01) and t1/2 (P < 0.05) of tolbutamide, and a distinct increase in CL (P<0.01). Many pharmacokinetic parameters of dextromethorphan in COL-treated rats were affected significantly, which indicated that the metabolism of dextromethorphan in these treatment groups was evidently slowed down. However, there was no significant influence of pharmacokinetic parameters of phenacetin and omeprazole in COL-treated rats. The results from the present in vivo study suggested that COL showed no effects on rat CYP1A2 and CYP2C19, however, it demonstrated potential inductive effects on CYP2C9 and inhibitory effects on CYP2D6. Therefore, caution is needed when COL is co-administered with drugs metabolized by CYP2C9 or CYP2D6, which may result in altered plasma concentrations of these drugs and relevant drug-drug interactions.


Assuntos
Colchicina/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Inibidores Enzimáticos/farmacologia , Supressores da Gota/farmacologia , Fígado/enzimologia , Animais , Cromatografia Líquida de Alta Pressão , Interações Medicamentosas , Meia-Vida , Técnicas In Vitro , Isoenzimas/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Espectrometria de Massas , Preparações Farmacêuticas/metabolismo , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
4.
Eur J Gastroenterol Hepatol ; 36(11): 1305-1313, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39166388

RESUMO

OBJECTIVE: The aim of this study is to systematically examine and compare the characteristics distinguishing colorectal adenomatous polyps from normal mucosal intestinal microbiota. METHODS: A total of 30 specimens were obtained from patients diagnosed with colorectal adenomatous polyps (adenoma group) who underwent endoscopic removal at Wenzhou People's Hospital between September 2021 and November 2021. Concurrently, 30 normal mucosal specimens were collected from patients without adenomatous polyps (control group). Subsequently, microbiome total DNA extraction was carried out, followed by PCR amplification targeting the V3-V4 region of the 16S rDNA. High-throughput sequencing was conducted using the Illumina MiSeq platform. Subsequent to sequencing, bioinformatics analysis was used to assess the diversity, composition, and functional aspects of the intestinal microbiota in both study groups. RESULTS: A notable dissimilarity in the microbiota structure was identified, specifically within the transverse colon, between these two groups ( P  < 0.05). Species composition analysis revealed that Escherichia , Fusobacterium , and Bacteroides were predominant bacteria in both groups, with Escherichia and Enterobacter displaying significant differences at the genera level between the control group and the adenoma group ( P  < 0.05). Correlation analysis and functional prediction demonstrated substantial disparities in interactions among dominant intestinal microbial genera within patients from both groups. Additionally, it was discovered that the intestinal microbiomes in patients in the adenoma group exhibited a significantly higher pathogenic potential. CONCLUSION: Upon conducting a comprehensive analysis, it was discerned that the microbiota present in the transverse colon of the control group exhibited distinctive characteristics that may contribute to the maintenance of intestinal health.


Assuntos
Pólipos Adenomatosos , Neoplasias Colorretais , Microbioma Gastrointestinal , Mucosa Intestinal , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Pólipos Adenomatosos/microbiologia , Pólipos Adenomatosos/patologia , Mucosa Intestinal/microbiologia , Neoplasias Colorretais/microbiologia , Idoso , Adulto , Estudos de Casos e Controles , RNA Ribossômico 16S/genética , Fusobacterium/isolamento & purificação , Fusobacterium/genética , Sequenciamento de Nucleotídeos em Larga Escala , Bacteroides/isolamento & purificação , Bacteroides/genética , Enterobacter/isolamento & purificação , Enterobacter/genética , Pólipos do Colo/microbiologia , Bactérias/isolamento & purificação , Bactérias/genética , Bactérias/classificação , DNA Bacteriano/isolamento & purificação , DNA Bacteriano/análise
5.
Heliyon ; 9(2): e13191, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36852074

RESUMO

Background: Hsa_circ_0072309 has been identified as a tumor suppressor in several carcinomas. However, its precise role in gastric cancer (GC) remains largely unknown. This study was aimed to explore the precise role of Hsa_circ_0072309 in GC. Methods: The transcriptional and clinical data of stomach adenocarcinoma were downloaded using the University of California SantaCruz (UCSC) Xena browser. The circular RNA (circRNA) datasets were obtained from the Gene Expression Omnibus (GEO) database. The expression profile and survival analysis of differentially expressed micro RNAs (DEMIs) and differentially expressed messenger RNAs (DEMs) were performed. Correlations between the expression and immune infiltration of the DEMS were studied. Additionally, the expression of hsa_circ_0072309 in GC tissues and cell lines were validated, and the relationship between its expression and clinical features was investigated. Gain- and loss-of function experiments and molecular interaction experiments were also conducted. Results: Overall, 7 differentially expressed circRNAs, 13 DEMIs, and 17 DEMs were screened. Two DEMIs (hsa_miR-34a-3p and hsa_miR-326) and five DEMs (C7, MARCKSL1, UBE2T, OLR1, and HOXC11) showed significant differences in the high- and low-risk groups. The most significantly enriched Gene Ontology terms were the circadian regulation of gene expression and protein binding. The most significantly enriched Kyoto Encyclopedia of Genes and Genomes pathways were the PI3K-Akt and Ras signal pathways. Additionally, six genes were significantly correlated with immune infiltration. The real-time quantitative PCR (RT-qPCR) results revealed a significant downregulation of hsa_circ_0072309 in GC tissues related to tumor size, vascular invasion, and lymph node metastasis. A hsa_circ_0072309 overexpression suppressed whereas a hsa_circ_0072309 knockdown promoted GC cells proliferation and migration in vitro; in addition, hsa_circ_0072309 could directly bind to has-miR-34a-3p and has-miR-330-5p. Conclusions: Hsa_circ_0072309 is a potential diagnostic biomarker for GC, and complement component 7 may be a tumor suppressor. These may potentially predict the prognosis of patients with GC and may become new therapeutic targets.

6.
Transpl Immunol ; 77: 101793, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36773765

RESUMO

BACKGROUND: Circular RNA (circRNA) has been proved to be an important regulator of gastric cancer (GC). However, the role and regulatory mechanism of circrna related competitive endogenous RNA (ceRNA) in GC have not been established. METHODS: CircRNA data and clinical data were obtained from the GEO and TCGA databases. The ceRNA networks were constructed and a function enrichment analysis was completed. Additionally, correlations between hub genes expression, immune cell infiltration, and clinical phenotypes were determined. The differentially expressed circRNAs and their downstream microRNAs (miRNAs) were validated by quantitative real-time polymerase chain reaction, and the hub genes were validated by western blot analysis. The migration and invasion ability of overexpressed hsa_circ_0002504 was determined by a transwell assay. RESULTS: The ceRNA network contained 2 circRNAs, 3 miRNAs, and 55 messenger RNAs (mRNAs). 323 biological processes terms, 53 cellular components terms, 51 molecular functions terms, and 4 signaling pathways were revealed by the function enrichment analysis. The GSEA analysis revealed that the hub genes were positively correlated with the axon guidance and adhesion molecules pathways. The correlation analysis revealed that overexpressed EPHA4 and KCNA1 indicated poor tissue differentiation and were associated with clinically advanced stages of GC. The in vitro experiments showed that hsa_circ_0002504 was significantly down-regulated in GC cell lines. In addition, the overexpression of hsa_circ_0002504 led to a significant downregulation of hsa-miR-615-5p and hsa-miR-767-5p, as well as an upregulation of EPHA4, KCNA1, and NCAM1. Furthermore, it suppressed the migration and invasion ability of GC cells. CONCLUSIONS: Hsa_circ_0002504 is a potential diagnostic biomarker for GC. High expression of EPHA4 and KCNA1 may indicate poor prognosis.


Assuntos
MicroRNAs , Neoplasias Gástricas , Humanos , RNA Circular/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Proliferação de Células/genética , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética , Linhagem Celular Tumoral
7.
Int J Gen Med ; 14: 8805-8810, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858048

RESUMO

OBJECTIVE: To explore the correlation between changes in esophageal pressure and psychological status in patients with globus sensation. METHODS: A total of 40 patients with globus sensation who attended Wenzhou People's Hospital between August 2020 and February 2021 were divided into two groups based on the results of esophageal manometry: a high-pressure group and a non-high-pressure group. The duration of disease, clinical symptom score, and self-rating anxiety scale (SAS) were compared between the two groups to determine the relationship between changes in esophageal pressure and psychological status. RESULTS: All the patients before treatment were divided into a high-pressure group (n = 14) and a non-high-pressure group (n = 26) according to whether the resting pressure of the upper esophageal sphincter (UES) was greater than 104 mmHg. The differences between the high-pressure group and non-high-pressure group in duration of disease, clinical symptom score, and SAS were statistically significant (all P < 0.05). Anxiety was present in 12 patients in the high-pressure group and two patients in the non-high-pressure group. The difference between the the high-pressure group and non-high-pressure group in the incidence of anxiety was statistically significant (χ2 = 21.04 and P < 0.001). Pearson correlation analysis of the association between esophageal pressure and anxiety resulted in R = 0.74 and P < 0.001. CONCLUSION: Patients with globus sensation who develop anxiety were more likely to have high pressure in the upper esophageal sphincter.

8.
J Phys Chem Lett ; 11(9): 3738-3744, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32315184

RESUMO

Understanding the role of different solvent molecules for practical solid-liquid heterogeneous photocatalytic reactions is critical for determining the pathway of the reaction. In this study, the operando nuclear magnetic resonance (NMR) method, combined with density functional theory (DFT) calculations, was employed to evaluate the control effect of solvent water in the photocatalytic reforming mechanism of methanol with a Pt-TiO2 catalyst. Results indicate that the presence of water effectively promotes the formation of the HCHO intermediate but inhibits the H2 evolution originating from the switch of the hydrogen source of the H2 formation from CH3OH to H2O. More interestingly, as detected directly in the ab initio molecular dynamics simulation, a small amount of H2O can dissociate, and the evolved -OH species at Ti5c site can greatly reduce the C-H activation barrier of -CH3O, contributing to the formation of oxidation products (e.g., HOCH2OH and CH3OCH2OH) on the Pt-TiO2 surface.

9.
BMJ Open Gastroenterol ; 2(1): e000051, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26629359

RESUMO

OBJECTIVE: To examine if the hospitalisation trends of liver cirrhosis are changing with the changes of risk factors of the disease in China. DESIGN: Secondary analysis of hospitalisation records in the 31 top-ranking hospitals in Beijing. RESULTS: Between 2006 and 2010, hospitalisation from viral hepatitis cirrhosis (VHC) decreased by 10% (95% CI=5-14%, p<0.001), but non-viral hepatitis cirrhosis (NVHC) and alcoholic cirrhosis (AC) increased by 35% (26-46%, p<0.001) and 33% (19%- 47%, p<0.001), respectively. The age patterns of hospitalisation varied with different types of liver cirrhosis. The hospitalisation risks for patients with VHC and AC were significantly high in the age groups 40-49 and 50-59 years, but risks for those with NHVC were high in all age groups of 40 years or above. Overall male-to-female hospitalisation ratios for VHC, NVHC and AC were 2.71, 1.14 and 59.9, respectively. The sex ratio became smaller with time from 2006 to 2010 in hospitalised patients with VHC, but it substantially increased in those with NVHC during the same period. CONCLUSIONS: Hospitalisation rates for liver cirrhosis in Beijing are changing with time. The changes of viral hepatitis infection and alcohol consumption in the general population may cause these changes.

10.
Yao Xue Xue Bao ; 37(9): 709-12, 2002 Sep.
Artigo em Zh | MEDLINE | ID: mdl-12567896

RESUMO

AIM: To investigate the chemical constituents of the rhizome of Anemone raddeana Regel, so as to find new active compounds. METHODS: The ethanol extracts of the rhizome of Anemone raddeana were obtained by silica column, HPLC. The structures of the compounds were elucidated by means of physico-chemical method and spectral analysis (IR, FAB-MS, 1HNMR, 13CNMR, DEPT, 1H-1H COSY, HMQC, HMBC). RESULTS: Nine compounds were isolated and identified as 27-hydroxyolean-12(13)-en-28-oic acid-3-0-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside (1), eleutheroside K (2), Oleanolic acid-3-O-alpha-L-rhamnopyranosyl-(1-->2)-[beta-D- glucopyranosyl-(1-->4)]-alpha-L-arabinopyranoside (3), betulin (4), betulic acid (5), acetyloleamolic acid (6), evonymitol (7), oleamolic acid (8) and diosgenin (9). CONCLUSION: Compound 1 is a new compound, named raddeanoside 12. Compounds 3-7 were isolated from this plant for the first time.


Assuntos
Anemone/química , Plantas Medicinais/química , Saponinas/isolamento & purificação , Eleutherococcus , Estrutura Molecular , Triterpenos Pentacíclicos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Rizoma/química , Saponinas/química , Triterpenos/química , Triterpenos/isolamento & purificação , Ácido Betulínico
11.
Nat Prod Commun ; 5(2): 197-200, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20334126

RESUMO

Two new 27-hydroxyoleanolic acid type triterpenoid saponins were isolated from the rhizomes of Anemone raddeana Regel. The structures of the two compounds were elucidated as 27-hydroxyoleanolic acid 3-O-beta-D-glucopyranosyl (1 --> 2)-alpha-L-arabinopyranoside (1) and 3-O-alpha-L-rhamnopyranosyl (1 --> 2)[beta-D-glucopyranosyl (1 --> 4)]-alpha-L-arabinopyranosyl-27-hydroxyoleanolic acid 28-O-alpha-L-rhamnopyranosyl (1 --> 4)-beta-D-glucopyranosyl (1 --> 6)-beta-D-glucopyranoside (2) on the basis of chemical and spectral evidence.


Assuntos
Anemone/química , Ácido Oleanólico/análogos & derivados , Rizoma/química , Saponinas/química , Triterpenos/química , Estrutura Molecular , Ácido Oleanólico/química
12.
J Asian Nat Prod Res ; 7(3): 215-24, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15621629

RESUMO

We have investigated the role of ginsenoside Re (Re) in preventing 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced apoptosis of the substantia nigra neurons in the mouse model of Parkinson's disease (PD). C57BL mice have been administrated i.s.c. with MPTP to establish the PD model. Pretreatment groups were given different doses of Re (6.5, 13, 26 mg kg(-1)) i.g. for 13 days. Transmission electron microscope (TEM), tyrosine hydroxythase (TH) immunostaining and TDT-mediated dUTP nick-end labeling (TUNEL) staining have been used to observe the damage of substantia nigral neurons. To measure the expression of inducible nitric oxide synthase (iNOS), Bcl-2, Bax protein and expression of Bcl-2, Bax gene, immunohistochemistry and in situ hybridization have been explored respectively. Western blot analysis has been performed with anti-caspase-3. Pretreatment with Re (13, 26 mg kg(-1)) markedly increases TH-positive neurons and decreases the TUNEL-positive ratio compared with the MPTP model group. Furthermore, Re could enhance the expression of Bcl-2 protein and Bcl-2 mRNA, but reduce the expression of Bax, Bax mRNA, and iNOS, and weaken the cleavage of caspase-3. In summary, ginsenoside Re showed protection from MPTP-induced apoptosis in the PD model mouse nigral neurons and this effect may be attributable to upregulating the expression of Bcl-2 protein, downregulating the expression of Bax, and iNOS protein, and inhibiting the activation of caspase-3.


Assuntos
Apoptose/efeitos dos fármacos , Ginsenosídeos/farmacologia , Transtornos Parkinsonianos/tratamento farmacológico , Substância Negra/efeitos dos fármacos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Animais , Caspase 3 , Caspases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase/análise , Óxido Nítrico Sintase Tipo II , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/patologia , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/análise , Substância Negra/patologia , Proteína X Associada a bcl-2
13.
Biol Pharm Bull ; 27(6): 810-2, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15187423

RESUMO

The effect of (3,5,6-trimethylpyrazin-2-yl)methyl 2-[4-(2-methylpropyl)phenyl]propanoate (ITE) on type II collagen (CII)-induced arthritis in mice was studied. Mice were immunized twice with CII, ITE being given orally once a day for 40 d after the 1st immunization. Clinical assessment showed that ITE had no effect on the day of onset of arthritis but did lowered the incidence rate of arthritis and the arthritis score. And ITE had a marked suppressive effect on the mouse hind paw edema induced by CII. ITE suppressed the delayed-type mouse ear skin reaction to CII but had no effect on the level of serum anti-CII antibodies. These results suggest that ITE inhibits the development of CII-induced arthritis in mice by suppressing delayed-type hypersensitivity to CII.


Assuntos
Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Experimental/tratamento farmacológico , Colágeno Tipo II/toxicidade , Propionatos/química , Propionatos/uso terapêutico , Pirazinas/química , Pirazinas/uso terapêutico , Animais , Artrite Experimental/induzido quimicamente , Artrite Experimental/fisiopatologia , Relação Dose-Resposta a Droga , Masculino , Camundongos
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