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1.
J Org Chem ; 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34662127

RESUMO

Human drug metabolites (HDMs) are important chemicals widely used in drug-related studies. However, acquiring these enzyme-derived and regio-/stereo-selectively modified compounds through chemical approaches is complicated. PikC is a biosynthetic P450 enzyme involved in pikromycin biosynthesis from the bacterium Streptomyces venezuelae. Here, we identify the mutant PikCD50N as a potential biocatalyst, with a broad substrate scope, diversified product profile, and high catalytic efficiency, for preparation of HDMs. Remarkably, PikCD50N can mediate the drug-metabolizing reactions using the low-cost H2O2 as a direct electron and oxygen donor.

2.
Cell Biosci ; 11(1): 173, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34530917

RESUMO

BACKGROUND: Liver cancer is one of the most common malignancies in the world with a poor prognosis. Hepatocellular carcinoma (HCC) is the most prevalent primary liver cancer, accounting for 80-90% of cases. The initiation and progression of HCC are closely associated with chronic liver inflammation. In addition, HCC is often accompanied by cell senescence. Senescent hepatocytes can secrete various inflammatory factors, collectively called the senescence-associated secretory phenotype (SASP). The SASP has been confirmed to promote the occurrence of liver cancer by affecting the inflammatory microenvironment. However, its role and the underlying mechanism of hepatic SASP in hepatocarcinogenesis are not clearly understood. Therefore, a better understanding of the pathogenic mechanisms of the effect of the hepatic SASP on the occurrence of HCC is still needed. METHODS: The study aims to explore the role of SASP factors and the underlying mechanism in tumorigenesis and the progression of HCC in vivo. We used diethylnitrosamine (DEN) combined with carbon tetrachloride (CCl4) (DEN-CCl4) to establish liver cancer model in wild-type (WT) mice and Bcl3 knockout (Bcl3-/-) mice. ß-galactosidase (ß-gal) staining was performed to evaluate the degree of cellular senescence. Immunohistochemistry (IHC) were used to detect the degree of cellular senescence and the activation of macrophage. PCR chip and clinical tissue chip assays were used to estimate the RNA levels of SASP factors and NF-κB related genes, and their protein levels were examined by Western blot assays. RESULTS: DEN-CCl4 induced cellular senescence in mouse hepatocytes. In addition, senescent hepatocytes might release a variety of inflammatory factors that further activate macrophages, thereby changing the microenvironmental state and promoting the occurrence of HCC. Mechanistically, the NF-κB pathway is important because it regulates the SASP. Therefore, we used a PCR chip to detect the expression of NF-κB-related genes in senescent liver tissue. Our results showed that the expression of Bcl3 was increased in senescent hepatocytes, and knocking out Bcl3 significantly inhibited the secretion of hepatocyte SASP factors and the activation of macrophages, thereby inhibiting hepatocarcinogenesis. Finally, in clinical tissues adjacent to HCC tissues in patients, the expression of Bcl3 and IL-8 correlated with poor prognosis in HCC patients. CONCLUSION: The hepatic SASP can further induce the activation of macrophages during hepatocarcinogenesis, thereby promoting the occurrence of HCC, and that this process is closely related to the expression of Bcl3 in hepatocytes.

3.
Sci China Life Sci ; 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34480693

RESUMO

Directed evolution (DE) inspired by natural evolution (NE) has been achieving tremendous successes in protein/enzyme engineering. However, the conventional "one-protein-for-one-task" DE cannot match the "multi-proteins-for-multi-tasks" NE in terms of screening throughput and efficiency, thus often failing to meet the fast-growing demands for biocatalysts with desired properties. In this study, we design a novel "multi-enzymes-for-multi-substrates" (MEMS) DE model and establish the proof-of-concept by running a NE-mimicking and higher-throughput screening on the basis of "two-P450s-against-seven-substrates" (2P×7S) in one pot. With the multiplied throughput and improved hit rate, we witness a series of convergent evolution events of the two archetypal cytochrome P450 enzymes (P450 BM3 and P450cam) in laboratory. It is anticipated that the new strategy of MEMS DE will find broader application for a larger repertoire of enzymes in the future. Furthermore, structural and substrate docking analysis of the two functionally convergent P450 variants provide important insights into how distinct P450 active-sites can reach a common catalytic goal.

4.
J Hepatol ; 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34509526

RESUMO

BACKGROUND & AIMS: Intrahepatic cholangiocarcinoma (ICC) is a primary liver cancer with high aggressiveness and extremely poor prognosis. The role of circular RNAs (circRNAs) in ICC carcinogenesis and progression remains to be determined. METHODS: CircRNA microarray was performed to screen significantly up-regulated circRNAs in paired ICC and non-tumor tissues. Colony formation, transwell, and xenograft models were used to examine the role of circRNAs in ICC proliferation and metastasis. RNA pulldown, mass spectrometry, chromatin immunoprecipitation, RNA binding protein immunoprecipitation, chromatin isolation by RNA purification, electrophoretic mobility shift assay, and luciferase reporter assays were used to explore the molecular sponge role of the circRNA via binding to miRNAs, and the interaction between circRNA and RNA-binding proteins. RESULTS: Hsa_circ_0050898, which originated from exon 1 to exon 20 of the ACTN4 gene (named as circACTN4), was significantly upregulated in ICC. High circACTN4 expression was associated with enhanced tumor proliferation and metastasis in vitro and in vivo, as well as a worse prognosis following ICC resection. In addition, circACTN4 upregulated Yes-associated protein1 (YAP1) expression by sponging miR-424-5p. More importantly, circACTN4 also recruited Y-box binding protein 1 (YBX1) to stimulate Frizzled-7 (FZD7) transcription. Furthermore, circACTN4 overexpression in ICC cells enhanced the interaction between YAP1 and ß-catenin, which are the core components of the Hippo and Wnt signaling pathways, respectively. CONCLUSIONS: CircACTN4 was upregulated in ICC and promoted ICC proliferation and metastasis by acting as a molecular sponge of miR-424-5p, as well as by interacting with YBX1 to transcriptionally activate FZD7. These results suggested that circACTN4 is a potential prognostic marker and therapeutic target for ICC. LAY SUMMARY: A circular RNA (circACTN4) was highly expressed in intrahepatic cholangiocarcinoma (ICC). The expression level of circACTN4 was positively associated with tumor growth and metastasis through both the Hippo and Wnt signaling pathways.

5.
Exp Ther Med ; 22(2): 811, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34131434

RESUMO

Naringin (NRG) has been reported to exert cardioprotective effects against multiple cardiovascular diseases, including lipopolysaccharide-induced and hyperglycemia-induced myocardial injury. However, the role of NRG in myocardial ischemia/reperfusion (I/R) injury remains unclear. In the present study, the PI3K/Akt pathway was investigated to evaluate the possible mechanisms underlying the roles of NRG in myocardial ischemia/reperfusion (I/R) injury. The levels of cardiac enzymes were measured by ELISA to evaluate the optimal dosage of NRG that could protect against myocardial I/R injury. Rats were administered 100 mg/kg of NRG and activities of myocardial enzymes, the level of cardiac apoptosis and inflammation, oxidant response, autophagy indicators and echocardiography were evaluated. The level of corresponding proteins was measured using western blotting. The results indicated that NRG elicited the best cardioprotective effects at a dose of 100 mg/kg by significantly reducing the levels of myocardial enzymes, apoptosis, inflammation, oxidative response and infarct size. Furthermore, NRG alleviated contractile dysfunction by increasing the left ventricular ejection fraction and fractional shortening. In addition, NRG markedly promoted the phosphorylation of Akt, while decreasing the level of autophagy indicator beclin-1 and the microtubule-associated protein 1B-light chain 3 (LC3B) II/ LC3BI ratio. However, PI3K/Akt inhibitor (LY294002) partially reduced the NRG induced phosphorylation of Akt and the reduction in beclin-1, along with the LC3BII/LC3BI ratio. The results of the present study demonstrated that NRG could attenuate myocardial I/R injury.

6.
FEBS J ; 288(19): 5768-5780, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33843134

RESUMO

Mycophenolic acid (MPA) is a fungal natural product and first-line immunosuppressive drug for organ transplantations and autoimmune diseases. In the compartmentalized biosynthesis of MPA, the acyl-coenzyme A (CoA) hydrolase MpaH' located in peroxisomes catalyzes the highly specific hydrolysis of MPA-CoA to produce the final product MPA. The strict substrate specificity of MpaH' not only averts undesired hydrolysis of various cellular acyl-CoAs, but also prevents MPA-CoA from further peroxisomal ß-oxidation catabolism. To elucidate the structural basis for this important property, in this study, we solve the crystal structures of the substrate-free form of MpaH' and the MpaH'S139A mutant in complex with the product MPA. The MpaH' structure reveals a canonical α/ß-hydrolase fold with an unusually large cap domain and a rare location of the acidic residue D163 of catalytic triad after strand ß6. MpaH' also forms an atypical dimer with the unique C-terminal helices α13 and α14 arming the cap domain of the other protomer and indirectly participating in the substrate binding. With these characteristics, we propose that MpaH' and its homologs form a new subfamily of α/ß hydrolase fold protein. The crystal structure of MpaH'S139A /MPA complex and the modeled structure of MpaH'/MPA-CoA, together with the structure-guided mutagenesis analysis and isothermal titration calorimetry (ITC) measurements, provide important mechanistic insights into the high substrate specificity of MpaH'.


Assuntos
Acil Coenzima A/química , Hidrolases/ultraestrutura , Ácido Micofenólico/metabolismo , Peroxissomos/ultraestrutura , Sequência de Aminoácidos/genética , Domínio Catalítico/genética , Hidrolases/química , Hidrolases/genética , Ácido Micofenólico/química , Penicillium/genética , Penicillium/ultraestrutura , Peroxissomos/enzimologia , Estrutura Secundária de Proteína/genética , Especificidade por Substrato/genética
7.
Cancer Cell Int ; 21(1): 225, 2021 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-33865377

RESUMO

BACKGROUND: Intrahepatic cholangiocarcinoma (iCCA) is the second most common malignant hepatic tumor and has a high postoperative recurrence rate and a poor prognosis. The key roles of most tumor recurrence-associated molecules in iCCA remain unclear. This study aimed to explore hub genes related to the postsurgical recurrence of iCCA. METHOD: Differentially expressed genes (DEGs) between iCCA samples and normal liver samples were screened from The Cancer Genome Atlas (TCGA) database and used to construct a weighted gene coexpression network. Module-trait correlations were calculated to identify the key module related to recurrence in iCCA patients. Genes in the key module were subjected to functional enrichment analysis, and candidate hub genes were filtered through coexpression and protein-protein interaction (PPI) network analysis. Validation studies were conducted to detect the "real" hub gene. Furthermore, the biological functions and the underlying mechanism of the real hub gene in iCCA tumorigenesis and progression were determined via in vitro experiments. RESULTS: A total of 1019 DEGs were filtered and used to construct four coexpression modules. The red module, which showed the highest correlations with the recurrence status, family history, and day to death of patients, was identified as the key module. Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses demonstrated that genes in the red module were enriched in genes and pathways related to tumorigenesis and tumor progression. We performed validation studies and identified estrogen receptor 1 (ESR1), which significantly impacted the prognosis of iCCA patients, as the real hub gene related to the recurrence of iCCA. The in vitro experiments demonstrated that ESR1 overexpression significantly suppressed cell proliferation, migration, and invasion, whereas ESR1 knockdown elicited opposite effects. Further investigation into the mechanism demonstrated that ESR1 acts as a tumor suppressor by inhibiting the JAK/STAT3 signaling pathway. CONCLUSIONS: ESR1 was identified as the real hub gene related to the recurrence of iCCA that plays a critical tumor suppressor role in iCCA progression. ESR1 significantly impacts the prognosis of iCCA patients and markedly suppresses cholangiocarcinoma cell proliferation, migration and invasion by inhibiting JAK/STAT3 signaling pathway.

8.
Mol Ther Nucleic Acids ; 23: 1066-1077, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33664991

RESUMO

The hepatoprotection of histone deacetylase sirtuin 1 (SIRT1) has been identified to attenuate ischemia-reperfusion (IR)-triggered inflammation and liver damage. This study was performed to characterize the function of SIRT1 in hepatic IR injury. In in vivo assays on liver-specific knockout mice of SIRT1, we first validated the effect of SIRT1 knockout on liver damage and XBP1/NLRP3 inflammasome activation. Next, we examined whether knockdown of XBP1/NLRP3 or miR-182 agomir could reverse the effect of SIRT1 knockout. In in vitro assays, NCTC1469 cells subjected to hypoxia/reoxygenation (H/R) were transduced with small interfering RNA (siRNA)/activator of SIRT1 or miR-182 agomir to confirm the effect of SIRT1 on NCTC1469 cell behaviors as well as the regulation of miR-182 and the XBP1/NLRP3 signaling pathway. Hepatic IR injury was appreciably aggravated in SIRT1 knockout mice, and SIRT1 knockdown abolished the inhibition of XBP1/NLRP3 inflammasome activation, which was reversed by NLRP3 knockdown, XBP1 knockdown, or miR-182 agomir. Mechanistically, miR-182 expression was positively regulated by SIRT1 in hepatic IR injury in mice, and miR-182 inhibited the expression of XBP1 by binding to the 3' untranslated region (UTR) of XBP1. The histone deacetylase SIRT1 inhibits the downstream XBP1/NLRP3 inflammatory pathway by activating miR-182, thus alleviating hepatic IR injury in mice.

9.
Nat Commun ; 12(1): 296, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436600

RESUMO

Nonribosomal peptide synthetases containing starter condensation domains direct the biosynthesis of nonribosomal lipopeptides, which generally exhibit wide bioactivities. The acyl chain has strong impacts on bioactivity and toxicity, but the lack of an in-depth understanding of starter condensation domain-mediated lipoinitiation limits the bioengineering of NRPSs to obtain novel derivatives with desired acyl chains. Here, we show that the acyl chains of the lipopeptides rhizomide, holrhizin, and glidobactin were modified by engineering the starter condensation domain, suggesting a workable approach to change the acyl chain. Based on the structure of the mutated starter condensation domain of rhizomide biosynthetic enzyme RzmA in complex with octanoyl-CoA and related point mutation experiments, we identify a set of residues responsible for the selectivity of substrate acyl chains and extend the acyl chains from acetyl to palmitoyl. Furthermore, we illustrate three possible conformational states of starter condensation domains during the reaction cycle of the lipoinitiation process. Our studies provide further insights into the mechanism of lipoinitiation and the engineering of nonribosomal peptide synthetases.


Assuntos
Lipídeos/química , Biossíntese de Peptídeos Independentes de Ácido Nucleico , Engenharia de Proteínas , Acilação , Sequência de Aminoácidos , Lipopeptídeos/química , Lipopeptídeos/metabolismo , Modelos Moleculares , Mutação Puntual/genética , Domínios Proteicos , Especificidade por Substrato
10.
Ecotoxicol Environ Saf ; 208: 111508, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33142159

RESUMO

BACKGROUND: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia with several risk factors. Recent studies have suggested that the exposure to air pollutants may increase the prevalence of AF, we evaluated those studies systematically to better elucidate the correlation between exposure to air pollution and AF. METHOD: We conducted a systematic review of publications using PubMed, Embase, the Cochrane library and Web of Science to explore the association between air pollutants and AF within the general population. The chosen studies were published until 7 July 2020. According to different study designs, we divided the outcomes into "short-term-exposure group" and "long-term-exposure group" for each pollutant. We used I2 statistics and Q-test to examine statistical heterogeneity, and sensitivity analysis to exclude the heterogeneous study. Fixed or random-effect model was used to combine the effects. Final result was presented as the OR and 95% CI of AF prevalence for every 10 µg/m3 increase in the concentration of PM2.5 and PM10;10 ppb increase in the concentration of SO2 ,NO2 ,O3; and 1 ppm increase in the CO concentration. RESULTS: Our analysis contain 18 studies. Underlying short-term exposure effect, for each increment of 10 µg/m3 in the PM2.5 concentration, the combined OR of AF prevalence was 1.01(1.00-1.02), for PM10 was 1.03(1.01-1.05). For a 10 ppb increment in the concentration of SO2, NO2, and O3 was 1.05(1.01-1.09), 1.03(1.01-1.04), and 1.01(0.97-1.06), respectively, for a 1 ppm increase of CO concentration was 1.02(0.99-1.06). Underlying long-term-exposure effect for each increment of 10 µg/m3 in the PM2.5 concentration; the combined OR of AF prevalence was 1.07(1.04-1.10) and that for PM10 was 1.03(1.03-1.04) For a 10 ppb increment in the NO2 concentration was 1.02(1.00-1.04). CONCLUSION: Our meta-analysis indicated that all air pollutants exposure had an adverse effect on AF prevalence in general population.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Fibrilação Atrial/epidemiologia , Exposição Ambiental/estatística & dados numéricos , Poluição do Ar/efeitos adversos , Fibrilação Atrial/induzido quimicamente , Exposição Ambiental/análise , Humanos , Material Particulado/análise , Fatores de Risco , Fatores de Tempo
11.
Cell Death Dis ; 11(10): 894, 2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-33093444

RESUMO

Long non-coding RNAs (lncRNAs) have extremely complex roles in the progression of intrahepatic cholangiocarcinoma (ICC) and remain to be elucidated. By cytological and animal model experiments, this study demonstrated that the expression of lncRNA MNX1-AS1 was remarkably elevated in ICC cell lines and tissues, and was highly and positively correlated with motor neuron and pancreas homeobox protein 1 (MNX1) expression. MNX1-AS1 significantly facilitated the proliferation, migration, invasion, and angiogenesis in ICC cells in vitro, and remarkably promoted tumor growth and metastasis in vivo. Further study revealed that MNX1-AS1 promoted the expression of MNX1 via recruiting transcription factors c-Myc and myc-associated zinc finger protein (MAZ). Furthermore, MNX1 upregulated the expression of Ajuba protein via binding to its promoter region, and subsequently, Ajuba protein suppressed the Hippo signaling pathway. Taken together, our results uncovered that MNX1-AS1 can facilitate ICC progression via MNX1-AS1/c-Myc and MAZ/MNX1/Ajuba/Hippo pathway, suggesting that MNX1-AS1 may be able to serve as a potential target for ICC treatment.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/patologia , Proteínas de Homeodomínio/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , RNA Longo não Codificante/fisiologia , Fatores de Transcrição/fisiologia , Adulto , Animais , Carcinogênese/genética , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas com Domínio LIM/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Transdução de Sinais , Fatores de Transcrição/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
12.
J Interv Card Electrophysiol ; 59(3): 595-601, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32918184

RESUMO

PURPOSE: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia with several risk factors. Recent studies have suggested that the exposure to fine particulate matter (PM2.5) increased the incidence of AF, but there is no meta-analysis of AF occurrence due to the exposure to PM2.5 in implantable cardioverter defibrillator (ICD) patients. METHODS: We conducted a systematic review of publication using PubMed, Embase, the Cochrane library, and Web of Science to explore the association between PM2.5 and AF within ICD patients. The chosen studies were published until June 11, 2020. The I2 statistic and Q test were used to examine statistical heterogeneity across studies. Further sensitivity analyses were carried out to ascertain the reason for heterogeneity. Fixed or random-effect model was used to combine the effects. Final result was presented as the OR with 95% CI of increased incidence of AF for every 10 µg/m3 PM2.5 concentration increased. RESULTS: After screening our analysis contained four studies and involved 1689 AF events from 572 patients. After using the random-effect model to combine the included study result, the overall OR was 1.24 (95% CI 1.00-1.53). CONCLUSION: Our meta-analysis indicated that PM2.5 exposure had an adverse effect on AF incidence in ICD patients.

13.
Front Oncol ; 10: 1210, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32903581

RESUMO

Hepatocellular carcinoma (HCC) samples were clustered into three energy metabolism-related molecular subtypes (C1, C2, and C3) with different prognosis using the gene expression data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). HCC energy metabolism-related molecular subtype analysis was conducted based on the 594 energy metabolism genes. Differential expression analysis yielded 576 differentially expressed genes (DEGs) among the three subtypes, which were closely related to HCC progression. Six genes were finally selected from the 576 DEGs through LASSO-Cox regression and used in constructing a six-gene signature-associated prognostic risk model, which was validated using the TCGA internal and three GEO external validation cohorts. The risk model showed that high ANLN, ENTPD2, TRIP13, PLAC8, and G6PD expression levels were associated with bad prognosis, and high expression of ADH1C was associated with a good prognosis. The validation results showed that our risk model had a high distinguishing ability of prognosis in HCC patients. The four enriched pathways of the risk model were obtained by gene set enrichment analysis (GSEA) and found to be associated with the tumorigenesis and development of HCC, including the cell cycle, Wnt signaling pathway, drug metabolism cytochrome P450, and primary bile acid biosynthesis. The risk score calculated from the established risk model in 204 samples and other clinical characteristics were used in building a nomogram with a good prognostic prediction ability (C-index = 0.746, 95% CI = 0.714-0.777). The area under the curves (AUCs) of the nomogram model in 1-, 2-, and 3-years were 0.82, 0.77, and 0.79, respectively. Then, qRT-PCR and immunohistochemistry were used to validate the mRNA expression levels of the six genes, and significant differences in mRNA and gene expression were observed among the tumor and adjacent tissues. Overall, our study divided HCC patients into three energy metabolism-related molecular subtypes with different prognosis. Then, a risk model with a good performance in prognostic prediction was built using the TCGA dataset. This model can be used as an independent prognostic evaluation index for HCC patients.

14.
J Cancer ; 11(19): 5623-5634, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32913457

RESUMO

Background: This study aimed to establish a model predicting the prognosis of intrahepatic cholangiocarcinoma (ICC) patients with cirrhosis before liver resection (LR). Methods: An Eastern Hepatobiliary Surgery Hospital (EHBH) model using the preoperative factors was established in a training cohort (305 patients from 2006 to 2011) and validated in an internal validation cohort (113 patients from 2012 to 2014). Predictive performance and discrimination were evaluated and compared with other staging systems. Results: The EHBH model containing preoperative factors of carbohydrate antigen 19-9 (CA19-9), radiological tumor diameter, tumor number, and satellite nodules outperformed other staging systems in predicting the prognosis of ICC. A contour plot of 3-year survival probability and a nomogram to form two differentiated groups of patients (high-risk group and low-risk group) were constructed based on the EHBH model to help surgeons predicting the overall survival (OS) before LR. Patients from the high-risk group (>86.56 points) in the training cohort had worse OS rates compared with those from the low-risk group (≤86.56 points). The one-, three-, and five-year OS rates were 50.4%, 29.0%, and 21.0% for the high-risk group and 68.2%, 45.5%, and 39.7% for the low-risk group, respectively (P<0.001). The same results were obtained in the internal validation patients. Conclusion: The contour plot is an easy-to-use tool to individually show the 3-year prognosis of ICC patients with different preoperative CA19-9 values and radiological characteristics before surgery. The EHBH model was suitable for selecting cirrhotic patients for LR to acquire a better survival.

15.
Synth Syst Biotechnol ; 5(3): 236-243, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32775708

RESUMO

The cytochrome P450 enzyme CYP-sb21 from the rare actinomycete Sebekia benihana is capable of hydroxylating the immunosuppressive drug molecule cyclosporine A (CsA) primarily at the 4th N-methyl leucine (MeLeu4), giving rise to γ-hydroxy-N-methyl-l-Leu4-CsA (CsA-4-OH). This oxidative modification of CsA leads to dramatically reduced immunosuppressive activity while retaining the hair growth-promoting side-effect, thus demonstrating great application potential in both pharmaceutical and cosmetic industries. However, this P450 enzyme also hydroxylates CsA at the unwanted position of the 9th N-methyl leucine (MeLeu9), indicating that the regioselectivity needs to be improved for the development of CsA-4-OH into a commercial hair growth stimulator. Herein, we report the crystal structure of CYP-sb21 in its substrate-free form at 1.85 Å. Together with sequence and 3D structure comparisons, Autodock-based substrate docking, molecular dynamics (MD) simulation, and site-directed mutagenesis, we identified a number of key residues including R294, E264, and M179 that can improve catalytic efficiency or change the regioselectivity of CYP-sb21 towards CsA, setting the stage for better enzymatic preparation of CsA-4-OH. This study also provides new insights into the substrate recognition and binding mechanism of P450 enzymes that accommodate bulky substrates.

16.
J Cancer ; 11(17): 4947-4956, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32742442

RESUMO

Background: This study developed a novel inflammation score system to predict survival outcomes using preoperational inflammatory markers in hepatocellular carcinoma (HCC) after surgery. Materials and Methods: An inflammation score system was developed using five preoperative inflammatory markers based on the clinical data of 455 HCC patients (training cohort) receiving radical resection in the Eastern Hepatobiliary Surgery Hospital. The system was validated using a cohort from a different hospital (external validation). Kaplan-Meier curves and log-rank test were used to compare the survival of patients with different inflammation scores. A nomogram including inflammation scores for survival prediction was created to exhibit the risk factors of overall survival (OS). Results: The patients in the low-score group showed better OS and recurrence-free survival (RFS) in the training and external validation cohorts than those from the high-score group. Subgroup analysis showed that compared with patients in the training cohort from the high-score group, stage I (eighth TNM stage) patients in the low-score group exhibited better prognosis results, whereas the findings for Stage II and III patients were different. Multivariate Cox analysis revealed that high inflammation score is an independent risk factor of OS and RFS. The nomogram established using the inflammation score with the C-index value of 0.661 (95% confidence interval=0.624-0.698) revealed a good three- and five-year calibration curves. Conclusions: The inflammation score system based on five preoperative inflammatory markers well predicted the survival of HCC patients after surgery, especially in those at the early stage (Stage I).

17.
Nanotechnology ; 31(2): 025603, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31550692

RESUMO

Nanotubes are prone to collapsing under compression due to the competition between the bending stiffness of the walls and the van der Waals interactions. The different radial morphologies during collapse may affect the electrical properties of nanotube, which may find promising potential applications in strain engineering. In this paper, the finite-deformation model is introduced to determine the radial morphologies, energy barrier and radial deformability of a nanotube under compression, in which the adhesion interactions are analytically obtained. The analytical solutions of the radial morphologies during compression are consistent with the molecular dynamics simulations results, indicating the effectiveness of the finite-deformation model. The analytical results reveal that both the energy barrier and the radial deformability show a decreasing tendency with the increase of the nanotube diameter.

18.
Int J Biol Macromol ; 141: 1065-1071, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31518623

RESUMO

Helicteres angustifolia L. is a familiar herbal plant, which exhibits various bioactivities with potential benefits for human health. In this study, the simulated digestion (saliva, simulated gastric and small intestinal conditions) and fermentation in vitro of polysaccharides from H. angustifolia L. (HaLPs) were evaluated, and the effects of HaLPs on gut microbiota were examined using high-throughput sequencing technology. The results indicated that the simulated gastrointestinal digestion had no effect on HaLPs, so HaLPs could reach the large intestine safely. However, the molecular weight of HaLPs and the reducing sugar decreased significantly after fermentation under anaerobic conditions. It was found that HaLPs had the significantly alternation effect on the composition of the gut microbiota. Furthermore, the total short-chain fatty acids content increased significantly after fermentation (from 2.25 ±â€¯0.13 mM to 22.45 ±â€¯4.56 mM). These results provided an understanding of the digestive characteristics of HaLPs and afforded a viable basis for their development.


Assuntos
Biomimética , Digestão , Fermentação , Microbioma Gastrointestinal , Malvaceae/química , Polissacarídeos/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Polissacarídeos/farmacologia
19.
Zhongguo Fei Ai Za Zhi ; 22(6): 349-354, 2019 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-31196368

RESUMO

BACKGROUND: Preoperative computed tomography (CT) guided microcoil localization is a common method for small lung nodules before video-assisted thoracoscopic surgery (VATS). However, this method still has some limitation such as complicated operation and slight complications. We have optimized the original method. The purpose of this study was to investigate the clinical value of this optimized method. METHODS: 35 pulmonary nodules from 31 patients between September 2018 and January 2019 were localized by the optimized method before VATS. The success rate, complications, pathological results and localization operations related data were statistically analyzed. RESULTS: The success rate of localization was 97.1%, and the success rate of VATS removal was 100%. The average operation time was 10.1 min (5 min-31 min), and the average time required for resection of lesions was 38.2 min (10 min-100 min). During the surgery, the microcoil of one patient was found to be dislocated and retracted into the chest wall. A puncture needle was inserted intolung tissue from the chest wall puncture point after the lung was inflated, and then the pulmonary nodule were successfully located and removed. A minor pneumothorax occurred in 3 patients, but no closed drainage was needed. Three patients developed intrapulmonary hematoma. The pathological results of 35 pulmonary nodules included 15 well-differentiated adenocarcinoma, 7 carcinoma in situ, 5 microinvasive adenocarcinoma, 4 atypical adenomatoid hyperplasia, 2 intrapulmonary lymph node hyperplasia, 2 inflammatory nodules. CONCLUSIONS: For small pulmonary nodules requiring thoracoscopic surgery, the optimized computed tomography-guided pulmonary nodule microcoil localization technique is convenient, safe and effective, and worthy of promotion to use.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Neoplasias Pulmonares/cirurgia , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia , Masculino , Pessoa de Meia-Idade , Nódulos Pulmonares Múltiplos/cirurgia , Cirurgia Torácica Vídeoassistida , Tomografia Computadorizada por Raios X , Adulto Jovem
20.
Proc Natl Acad Sci U S A ; 116(27): 13305-13310, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31209052

RESUMO

Mycophenolic acid (MPA) from filamentous fungi is the first natural product antibiotic to be isolated and crystallized, and a first-line immunosuppressive drug for organ transplantations and autoimmune diseases. However, some key biosynthetic mechanisms of such an old and important molecule have remained unclear. Here, we elucidate the MPA biosynthetic pathway that features both compartmentalized enzymatic steps and unique cooperation between biosynthetic and ß-oxidation catabolism machineries based on targeted gene inactivation, feeding experiments in heterologous expression hosts, enzyme functional characterization and kinetic analysis, and microscopic observation of protein subcellular localization. Besides identification of the oxygenase MpaB' as the long-sought key enzyme responsible for the oxidative cleavage of the farnesyl side chain, we reveal the intriguing pattern of compartmentalization for the MPA biosynthetic enzymes, including the cytosolic polyketide synthase MpaC' and O-methyltransferase MpaG', the Golgi apparatus-associated prenyltransferase MpaA', the endoplasmic reticulum-bound oxygenase MpaB' and P450-hydrolase fusion enzyme MpaDE', and the peroxisomal acyl-coenzyme A (CoA) hydrolase MpaH'. The whole pathway is elegantly comediated by these compartmentalized enzymes, together with the peroxisomal ß-oxidation machinery. Beyond characterizing the remaining outstanding steps of the MPA biosynthetic steps, our study highlights the importance of considering subcellular contexts and the broader cellular metabolism in natural product biosynthesis.


Assuntos
Ácido Micofenólico/metabolismo , Aspergillus oryzae/metabolismo , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Redes e Vias Metabólicas , Oxirredução , Penicillium/metabolismo , Peroxissomos/metabolismo , Frações Subcelulares/enzimologia , Frações Subcelulares/metabolismo
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