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1.
Biomed Pharmacother ; 134: 111149, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33385683

RESUMEN

E. coli is associated with high rates of infection and resistance to drugs not only in China but also the rest of the world. In addition, the number of E. coli biofilm infections continue to increase with time. Notably, biofilms are attractive targets for the prevention of infections caused by multidrug-resistant bacteria. Moreover, the pgaABCD-encoded Poly-ß-1,6-N-acetyl-d-glucosamine (PNAG) plays an important role in biofilm formation. Therefore, this study aimed to explore the specific effect of the (R)-(+)-pulegone (PU) on growth and biofilm formation in multi-drug resistant E. coli. The molecular mechanisms involved were also examined. The results showed that PU had significant antibacterial and antibiofilm formation activity against E. coli K1, with MIC and MBC values of 23.68 and 47.35 mg/mL, respectively. On the other hand, the maximum inhibition rate for biofilm formation in the bacterium was 52.36 % at 94.70 mg/mL of PU. qRT-PCR data showed that PU significantly down-regulated expression of the pgaABCD genes (P < 0.05). PU was also broadly effective against biofilm formation in MG1655 and MG1655/ΔpgaABCD, exhibiting the maximum inhibition rates were 98.23 % and 93.35 %, respectively. In addition, PU destroyed pre-formed mature biofilm in both MG1655 and MG1655/ΔpgaABCD about 95.03 % and 92.4 %, respectively. The study therefore verified that pgaA was a potential and key target for PU in E. coli although it was not the only one. Overall, the findings indicated that PU is a potential and novel inhibitor of drug resistance, This therefore gives insights on new ways of preventing and treating biofilm-associated infections in the food industry as well as in clinical practice.


Asunto(s)
Antibacterianos/farmacología , Proteínas de la Membrana Bacteriana Externa/genética , Biopelículas/efectos de los fármacos , Monoterpenos Ciclohexánicos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Escherichia coli K12/efectos de los fármacos , Proteínas de Escherichia coli/genética , Amidohidrolasas/genética , Biopelículas/crecimiento & desarrollo , Escherichia coli K12/genética , Escherichia coli K12/crecimiento & desarrollo , Regulación Bacteriana de la Expresión Génica , Pruebas de Sensibilidad Microbiana
2.
Electrophoresis ; 2020 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-33247595

RESUMEN

Polyethylene glycol-modified canine uricase (PEG-UHC) was prepared by modifying the ε-amino group of lysine residues on the canine uricase (UHC) protein to near-saturation with 5 kDa monomethoxyl-polyethylene glycol succinimide (mPEG-SPA-5k). In order to accurately determine the PEGylation uniformity of PEG-UHC, CZE, 3-8% gradient gel SDS-PAGE, and imaging CIEF (iCIEF) analyses were compared. CZE could not effectively separate PEG-UHC proteins with different degrees of modification, 3-8% gradient gel SDS-PAGE could separate PEG-UHC into seven gel bands; however, most of the gel bands were smeared or blurred, and the separation of PEG-UHC samples by iCIEF was significantly better than that by 3-8% gradient gel SDS-PAGE. Under denatured conditions, iCIEF separated 12 pI peaks, and could also accurately quantify the relative monomer PEG-UHC content. More than 85% of the total monomeric PEG-UHC was conjugated with 7-12 PEG molecules; of this 85%, approximately 40% was conjugated with 9-10 PEG molecules. These results demonstrated that iCIEF exhibits good potential for determining the PEGylation homogeneity of PEGylated protein drugs. This article is protected by copyright. All rights reserved.

3.
Chaos ; 30(7): 073118, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32752620

RESUMEN

The role of sequence complexity in 23 051 somatic missense mutations including 73 well-known mutation hotspots across 22 major cancers was studied in human TP53 proteins. A role for sequence complexity in TP53 protein mutations is suggested since (i) the mutation rate significantly increases in low amino acid pair bias complexity; (ii) probability distribution complexity increases following single point substitution mutations and strikingly increases after mutation at the mutation hotspots including six detectable hotspot mutations (R175, G245, R248, R249, R273, and R282); and (iii) the degree of increase in distribution complexity is significantly correlated with the frequency of missense mutations (r = -0.5758, P < 0.0001) across 20 major types of solid tumors. These results are consistent with the hypothesis that amino acid pair bias and distribution probability may be used as novel measures for protein sequence complexity, and the degree of complexity is related to its susceptibility to mutation, as such, it may be used as a predictor for modeling protein mutations in human cancers.

4.
Materials (Basel) ; 13(17)2020 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-32854175

RESUMEN

High aspect ratio tungsten nanowires have been prepared by selective dissolution of Nickel-aluminum-tungsten (NiAl-W) alloys which were directionally solidified at growth rates varying from 2 to 25 µm/s with a temperature gradient of 300 K·cm-1. Young's modulus and electrical resistivity of tungsten nanowires were measured by metallic mask template method. The results show that the tungsten nanowires with uniform diameter and high aspect ratio are well aligned. The length of tungsten nanowires increases with prolongation of etching time, and their length reaches 300 µm at 14 h. Young's modulus of tungsten nanowires is estimated by Hertz and Sneddon models. The Sneddon model is proper for estimating the Young's modulus, and the value of calculating Young's modulus are 260-460 GPa which approach the value of bulk tungsten. The resistivity of tungsten nanowires is measured and fitted with Fuchs-Sondheimer (FS) + Mayadas-Shatzkes (MS) model. The fitting results show that the specific resistivity of W nanowires is a litter bigger than the bulk W, and its value decreases with decreasing diameter.

5.
Panminerva Med ; 2020 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-32414228

RESUMEN

BACKGROUND: To explore the clinical efficacy and safety of conversion surgery in the treatment of stage IV gastric cancer, and to analyze the influencing factors for the prognosis of patients. METHODS: The clinical data of 84 patients with stage IV gastric cancer treated in our hospital from September 2014 to March 2016 were collected. All patients were treated with S-1 + oxaliplatin or S-1 + docetaxel chemotherapy, among which 42 patients had surgical indications after chemotherapy and received gastrectomy (R0 resection or R1 resection) (conversion surgery group), and the remaining 42 patients had no surgical indications after chemotherapy (simple chemotherapy group). The patients in both groups were followed up to record the survival status, and the possible influencing factors for the prognosis were analyzed. RESULTS: In conversion surgery group, the median chemotherapy cycle was 4.3, and the objective response rate (ORR) was 73.8% (31/42). During chemotherapy in the two groups, there were 22 cases (52.3%) and 24 cases (57.1%) of hematological toxicity, and 28 cases (66.7%) and 32 cases (76.2%) of non-hematological toxicity, mainly in grade I-II, which could be relieved after symptomatic treatment, and chemotherapy was successfully completed. After chemotherapy, 42 out of 84 patients met the surgical indications. All patients were followed up for 6-36 months. The 3-year overall survival was 35.7% (15/42) and 9.5% (4/42), respectively, in the two groups, and the difference was statistically significant according to the log-rank test (P<0.05). The results of multivariate analysis showed that whether the surgical margin was R0 was an independent influencing factor for the prognosis of patients (HR=8.012, 95% CI=2.522-14.384, P=0.027). CONCLUSIONS: Radical surgery after conversion therapy can raise the survival rate of patients, with tolerable adverse reactions. Whether the surgical margin is R0 in conversion therapy is an independent influencing factor for the prognosis of patients with stage IV gastric cancer.

6.
Eur J Drug Metab Pharmacokinet ; 45(4): 445-451, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32162270

RESUMEN

BACKGROUND AND OBJECTIVE: Polyethylene glycol-modified canine uricase (PEG-UHC) prepared with a lower-molecular-weight (5 kDa) PEG is used to treat gout. This study investigated the comparative pharmacokinetics of single and multiple doses of PEG-UHC administered intravenously and a single dose of uricase (UHC) administered intravenously in cynomolgus monkeys. METHODS: A noncompartmental model was used to fit the plasma drug concentration-time curve and calculate the pharmacokinetic parameters of PEG-UHC, which were compared with those obtained for UHC at the equivalent dose (2 mg/kg). To study the pharmacokinetics after multiple dose administration, cynomolgus monkeys were administered five intravenous injections of PEG-UHC (0.5 mg/kg), with one injection performed every 15 days. RESULTS: The area under the curve (AUC) and the maximum plasma concentration (Cmax) of PEG-UHC were positively correlated with dose, whereas plasma half-life (t1/2) and clearance (CL) did not change significantly with increasing dose, suggesting that these pharmacokinetic characteristics are linear. Intravenous PEG-UHC exhibited an average t1/2 that was 125.79 times longer and an AUC0-t that was 64.45 times larger than the corresponding values for UHC at the same dose (2 mg/kg), while the CL of PEG-UHC was 1/72.73 times the CL of intravenous UHC. The plasma drug concentration reached a steady state after five injections, and the t1/2 values following the first and last drug administration did not differ significantly. CONCLUSION: Our data show that PEG-UHC is markedly superior to UHC in terms of duration of action, and that the pharmacokinetics of PEG-UHC in cynomolgus monkeys are linear. Sequential administration of PEG-UHC did not accelerate drug clearance. Our findings provide the basis for future clinical studies of PEG-UHC.

7.
Appl Environ Microbiol ; 86(9)2020 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-32086301

RESUMEN

The four regulatory genes fscR1 to fscR4 in Streptomyces sp. strain FR-008 form a genetic arrangement that is widely distributed in macrolide-producing bacteria. Our previous work has demonstrated that fscR1 and fscR4 are critical for production of the polyene antibiotic candicidin. In this study, we further characterized the roles of the other two regulatory genes, fscR2 and fscR3, focusing on the relationship between these four regulatory genes. Disruption of a single or multiple regulatory genes did not affect bacterial growth, but transcription of genes in the candicidin biosynthetic gene cluster decreased, and candicidin production was abolished, indicating a critical role for each of the four regulatory genes, including fscR2 and fscR3, in candicidin biosynthesis. We found that fscR1 to fscR4, although differentially expressed throughout the growth phase, displayed similar temporal expression patterns, with an abrupt increase in the early exponential phase, coincident with initial detection of antibiotic production in the same phase. Our data suggest that the four regulatory genes fscR1 to fscR4 have various degrees of control over structural genes in the biosynthetic cluster under the conditions examined. Extensive transcriptional analysis indicated that complex regulation exists between these four regulatory genes, forming a regulatory network, with fscR1 and fscR4 functioning at a lower level. Comprehensive cross-complementation analysis indicates that functional complementation is restricted among the four regulators and unidirectional, with fscR1 complementing the loss of fscR3 or -4 and fscR4 complementing loss of fscR2 Our study provides more insights into the roles of, and the regulatory network formed by, these four regulatory genes controlling production of an important pharmaceutical compound.IMPORTANCE The regulation of antibiotic biosynthesis by Streptomyces species is complex, especially for biosynthetic gene clusters with multiple regulatory genes. The biosynthetic gene cluster for the polyene antibiotic candicidin contains four consecutive regulatory genes, which encode regulatory proteins from different families and which form a subcluster within the larger biosynthetic gene cluster in Streptomyces sp. FR-008. Syntenic arrangements of these regulatory genes are widely distributed in polyene gene clusters, such as the amphotericin and nystatin gene clusters, suggesting a conserved regulatory mechanism controlling production of these clinically important medicines. However, the relationships between these multiple regulatory genes are unknown. In this study, we determined that each of these four regulatory genes is critical for candicidin production. Additionally, using transcriptional analyses, bioassays, high-performance liquid chromatography (HPLC) analysis, and genetic cross-complementation, we showed that FscR1 to FscR4 comprise a hierarchical regulatory network that controls candicidin production and is likely representative of how expression of other polyene biosynthetic gene clusters is controlled.


Asunto(s)
Antibacterianos/biosíntesis , Proteínas Bacterianas/metabolismo , Candicidina/biosíntesis , Regulación Bacteriana de la Expresión Génica , Streptomyces/metabolismo , Factores de Transcripción/metabolismo , Proteínas Bacterianas/genética , Diterpenos , Genes Bacterianos , Genes Reguladores , Streptomyces/genética , Factores de Transcripción/genética
8.
Mol Cancer Ther ; 19(1): 178-186, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31582530

RESUMEN

Viral-based chimeric antigen receptor-engineered T (CAR T)-cell manufacturing has potential safety risks and relatively high costs. The nonviral minicircle DNA (mcDNA) is safer for patients, cheaper to produce, and may be a more suitable technique to generate CAR T cells. In this study, we produced mcDNA-based CAR T cells specifically targeting prostate stem cell antigen (PSCA; mcDNA-PSCA-CAR T cells). Our results showed that mcDNA-PSCA-CAR T cells persisted in mouse peripheral blood as long as 28 days and demonstrated more CAR T-cell infiltration, higher cytokine secretion levels, and better antitumor effects. Together, our results suggest that mcDNA-CAR can be a safe and cost-effective platform to produce CAR T cells.

9.
Life Sci ; 255: 116892, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-31610209

RESUMEN

Low response rates and high immunogenicity were observed after repeated injections of pegloticase (Krystexxa) into gout patients during clinical trials. However, related research had not been reported in preclinical animal experiments, which has limited the development of this drug. In this study, the toxicity of mPEG-UHC was studied in rats and monkeys over a 26-week period of repeated intravenous dosing. There were no obvious toxic reactions in the tested animals, with the exception of mPEG-UHC blood clearance and immunogenicity. After repeated injections of mPEG-UHC, rapid loss of uricolytic activity (RLA) was not detected in rats, whereas RLA was observed in 44.4% of drug-treated monkeys. In these monkeys, RLA was observed in 11.1% of males and 77.8% of females, and such incidences increased with higher dosing. High titres of anti-uricase IgG antibodies were associated with RLA but did not result in any toxicity. Remission and recurrence of RLA occurred in one female monkey in the high-dose group because of suppressed and altered immune responses in this animal. The predicted incidence of RLA after repeated injections of mPEG-UHC in gout patients may be lower than that of pegloticase. In this study, the no-observed-adverse-effect levels (NOAELs) of mPEG-UHC in rats and monkeys were 32.0 mg/kg and 20.0 mg/kg, respectively. Therefore, the results showed that rats and monkeys could tolerate long-term and high-dose administrations of mPEG-UHC, and mPEG-UHC blood clearance and immunogenicity showed obvious species and sex differences. These findings will provide valuable information to direct the clinical use of mPEG-UHC.


Asunto(s)
Anticuerpos/inmunología , Supresores de la Gota/toxicidad , Inmunoglobulina G/inmunología , Polietilenglicoles/toxicidad , Urato Oxidasa/toxicidad , Animales , Femenino , Supresores de la Gota/administración & dosificación , Supresores de la Gota/inmunología , Macaca fascicularis , Masculino , Nivel sin Efectos Adversos Observados , Polietilenglicoles/administración & dosificación , Ratas , Ratas Sprague-Dawley , Factores Sexuales , Especificidad de la Especie , Urato Oxidasa/administración & dosificación , Urato Oxidasa/inmunología
10.
Int J Biol Macromol ; 136: 115-122, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31195041

RESUMEN

Diabetic patients often have lipid metabolism disorders, which can lead to life-threatening complications. In this study, we investigated the regulatory effects of polysaccharides extracted from Arctium lappa L. on lipid metabolism in diabetic rats. We constructed a diabetes mellitus mouse model with streptozocin, and treated the rats with A. lappa L. polysaccharide. The body weight analysis showed that the weight of diabetic rats significantly decreased, but the weight of the rats in the polysaccharide treatment groups increased and the ratio of liver weight to body weight also appeared the well effect (tending to normal group). Serum biochemical analysis showed that total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL), and the ratio of liver weight to body weight showed a downward trend. In addition, compared to TC/HDL, TG/HDL, and HDL/LDL, the relative content of HDL was increased. Meanwhile, we used Western blotting to detect changes in protein kinase C alpha (PKC-α), PKC-ß, P-selectin, nuclear factor kappa B (NF-κB), and phosphorylated NF-kB p65 in the liver. The results showed that the A. lappa L. polysaccharides regulated lipid metabolism through the PKC/NF-κB pathway in diabetic rats.


Asunto(s)
Antioxidantes/farmacología , Arctium/química , Diabetes Mellitus Experimental/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , FN-kappa B/metabolismo , Polisacáridos/farmacología , Proteína Quinasa C/metabolismo , Animales , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/patología , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
11.
Cancer Chemother Pharmacol ; 83(5): 911-920, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30848330

RESUMEN

Activation of programmed death-1 (PD-1) and cytotoxic T-lymphocyte antigen-4 (CTLA-4) on T cells leads to T cell exhaustion and ultimately facilitates tumor progression. Recent success of using immune cell checkpoint inhibitors offers a great promise to treat various cancers, including bladder cancer. However, the expression pattern and therapeutic value of PD-1 and CTLA-4 in peripheral blood T cells remain largely unexplored. In this study, we presume that disruption of the potential dysregulated checkpoint molecules in peripheral blood T cells may improve the anti-tumor efficacy of cytotoxic T cells in bladder cancer. We showed that both PD-1 and CTLA-4 expression were specifically elevated on CD8 + T cells but not CD4 + T cells in peripheral blood of patients with bladder cancer compared with that in healthy donors. Notably, CTLA-4 expression was significantly higher in muscle-invasive bladder cancer (MIBC) and correlated with tumor size. By blocking CTLA-4 with anti-CTLA-4 antibody and CRISPR-Cas9-mediated CTLA-4 disruption, we revealed that CTLA-4-disrupted CTLs had enhanced cellular immune response and superior cytotoxicity to the CD80/CD86-positive bladder cancer cells in vitro. Moreover, the CTLA-4-disrupted CTLs exhibited a pronounced anti-tumor effect in vivo as demonstrated by prophylactic assay and therapeutic assay in the subcutaneous xenograft model. Collectively, our findings confirm improved therapeutic efficacy of CTLA-4-disrupted CTLs and provides the potential strategy for targeting immune checkpoints to enhance the promising immunotherapy.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Antígeno CTLA-4/genética , Receptor de Muerte Celular Programada 1/genética , Neoplasias de la Vejiga Urinaria/patología , Animales , Estudios de Casos y Controles , Línea Celular Tumoral , Femenino , Humanos , Inmunoterapia/métodos , Masculino , Ratones , Ratones SCID , Persona de Mediana Edad , Neoplasias de la Vejiga Urinaria/inmunología , Ensayos Antitumor por Modelo de Xenoinjerto
12.
3 Biotech ; 8(11): 472, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30456006

RESUMEN

Mobile genetic elements involved in mediating horizontal transfer events contribute to bacterial evolution, and bacterial genomic plasticity and instability result in variation in functional genetic information in Streptomyces secondary metabolism. In a previous study, we reported the complete genome sequence of the industrial Streptomyces strain F613-1, which produces high yields of clavulanic acid. In this study, we used comparative genomics and bioinformatics to investigate the unique genomic features of this strain. Taken together, comparative genomics were used to systematically investigate secondary metabolism capabilities and indicated that frequent exchange of genetic materials between Streptomyces replicons may shape the remarkable diversities in their secondary metabolite repertoires. Moreover, a 136.9-kb giant region of plasticity (RGP) was found in the F613-1 chromosome, and the chromosome and plasmid pSCL4 are densely packed with an exceptionally large variety of potential secondary metabolic gene clusters, involving several determinants putatively accounting for antibiotic production. In addition, the differences in the architecture and size of plasmid pSCL4 between F613-1 and ATCC 27064 suggest that the pSCL4 plasmid could evolve from pSCL4-like and pSCL2-like extrachromosomal replicons. Furthermore, the genomic analyses revealed that strain F613-1 has developed specific genomic architectures and genetic patterns that are well suited to meet the requirements of industrial innovation processes.

13.
Fish Shellfish Immunol ; 82: 304-311, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30125699

RESUMEN

Honeysuckle stem had been used as feed additives to modulate immunity in breeding industry, which was limited in the aquaculture field. In this study, the immunomodulation of honeysuckle stem ethanol extract (designed as HSE) on Chinese mitten crab Eriocheir sinensis was detected. The crabs fed with HSE diets for 30 days had higher level of the total haemocyte count (HTC), lysozyme activity and PO activity (P < 0.05), and had no obvious affect on the phagocytic activity, NO and TNF-α level. When challenged with Aeromonas hydrophila (1.0 × 107 colony-forming units), HSE exhibited weak antibacterial activity against A. hydrophila and increased survival rate of crabs. The decreasing of THC and the increasing of TNF-α concentration, EsCaspase and EsLITAF mRNA expression level were all inhibited significantly by HSE treatment (P < 0.05), when the crabs were challenged by A. hydrophila. Moreover, the following immune parameters of crabs were enhanced by HSE treatment after A. hydrophila infection, including the rising of phagocytosis index and phagocytic rate of haemocyte, the rising of lysozyme, PO, NOS activities and nitric oxide concentration (P < 0.05). Therefore, it was concluded that HSE had great potential to develop into feed additive of crabs, which could enhance the innate immunity of Chinese mitten crabs E. sinensis effectively after A. hydrophila infection.


Asunto(s)
Braquiuros/inmunología , Inmunidad Innata/inmunología , Factores Inmunológicos/farmacología , Lonicera/química , Aeromonas hydrophila/fisiología , Animales , Braquiuros/microbiología , Extractos Vegetales/farmacología , Tallos de la Planta/química
14.
PLoS One ; 13(8): e0202966, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30142183

RESUMEN

Drought and vegetation conditions within the Damqu River Basin, part of the Yangtze River Source Region (YRSR), are assessed here using the standardized precipitation index (SPI), the standardized precipitation evapotranspiration index (SPEI), the normalized difference vegetation index (NDVI), and the leaf area index (LAI). We utilized Sen's method, least squares regression method, linear regression and Pearson's correlation analysis to study variations in drought and vegetation indices and the drought effect on vegetation between 1988 and 2015. Results reveal that droughts occurred at a 25% frequency over this period; SPI and SPEI analyses show that 1994, 1999, 2005, and 2010 were change points and that the basin was characterized by varying drought and humidity trends. Subsequent to 2010, both SPI and SPEI decreased within the basin, while 1995, 2000, 2004, and 2010 were change points for NDVI and LAI while the watershed exhibited variable trends in vegetation reduction and increase. The NDVI-annual values of 63.36% regions and the LAI-summer values of 68.39% areas within the basin were decreased during 1988-2015 and 2000-2015, respectively. Subsequent to 2010, both NDVI and LAI decreased within the basin and significant positive correlations at inter-annual and inter-summer time scales were seen in both drought and vegetation indices; drought has exerted a lag effect on vegetation as shown by significant positive correlations between annual SPI/SPEI values and following year NDVI/LAI values.


Asunto(s)
Sequías , Ecosistema , Monitoreo del Ambiente , Desarrollo de la Planta , Ríos , China , Estaciones del Año
15.
Oncotarget ; 9(4): 5208-5215, 2018 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-29435173

RESUMEN

Programmed cell death protein 1 (PD-1) is an immune checkpoint receptor that functions to attenuate T cell activation. In this study, we knocked out (KO) PD-1 in cytotoxic T lymphocytes (CTLs) using CRISPR-Cas9 system to evaluate its effect on the anti-tumor activity of the CTLs against multiple myeloma (MM). Results show that PD-1 KO CTLs facilitate apoptosis and caspase activation of the co-cultured MM cells and enhanced MM cell death by 36% compared with the control. PD-1 KO also increased TNF-α and IFN-γ secretion of the CTLs by 2.4 and 1.9-fold respectively. The effectiveness of PD-1 KO in enhancing anti-tumor activity of the CTLs was verified in vivo using mouse xenograft model. The xenografted mice treated with PD-1 KO CTLs demonstrated repressed MM tumor growth and prolonged survival compared with the control group. We conclude that CRISPR-Cas9 is an efficient system to knock out PD-1 from CTLs and PD-1 KO could significantly enhance the anti-tumor activity of CTLs.

16.
Genome Announc ; 6(1)2018 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-29301883

RESUMEN

Streptomyces gilvosporeus strain F607 is a producer of high levels of natamycin used in the fermentation industry. In this study, the complete genome sequence of strain F607 was determined. This genome sequence provides a basis for understanding natamycin biosynthesis and regulation in a high-natamycin-producing strain and will aid in the development of useful strategies for improving industrial strains.

17.
Eur J Med Chem ; 144: 444-492, 2018 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-29288945

RESUMEN

Oxazole compounds containing nitrogen and oxygen atoms in the five-membered aromatic ring are readily able to bind with a variety of enzymes and receptors in biological systems via diverse non-covalent interactions, and thus display versatile biological activities. The related researches in oxazole-based derivatives including oxazoles, isoxazoles, oxazolines, oxadiazoles, oxazolidones, benzoxazoles and so on, as medicinal drugs have been an extremely active topic, and numerous excellent achievements have been acquired. Noticeably, a large number of oxazole compounds as clinical drugs or candidates have been frequently employed for the treatment of various types of diseases, which have shown their large development value and wide potential as medicinal agents. This work systematically reviewed the recent researches and developments of the whole range of oxazole compounds as medicinal drugs, including antibacterial, antifungal, antiviral, antitubercular, anticancer, anti-inflammatory and analgesic, antidiabetic, antiparasitic, anti-obesitic, anti-neuropathic, antioxidative as well as other biological activities. The perspectives of the foreseeable future in the research and development of oxazole-based compounds as medicinal drugs are also presented. It is hoped that this review will serve as a stimulant for new thoughts in the quest for rational designs of more active and less toxic oxazole medicinal drugs.


Asunto(s)
Oxazoles/farmacología , Analgésicos/química , Analgésicos/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacología , Fármacos Antiobesidad/química , Fármacos Antiobesidad/farmacología , Antifúngicos/química , Antifúngicos/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Antiparasitarios/química , Antiparasitarios/farmacología , Antituberculosos/química , Antituberculosos/farmacología , Antivirales/química , Antivirales/farmacología , Química Farmacéutica , Humanos , Hipoglucemiantes/química , Hipoglucemiantes/farmacología , Estructura Molecular , Oxazoles/química
18.
Med Sci Monit ; 23: 5599-5612, 2017 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-29172017

RESUMEN

BACKGROUND Nonalcoholic fatty liver disease (NAFLD) is a condition characterized by excessive fat accumulation in the form of triglycerides. The incidence of NAFLD and hyperlipidemia, with their associated risks of end-stage liver and cardiovascular diseases, is increasing rapidly. This study aimed to investigate the effects of scutellarin on the experimental NAFLD in high-fat diet fed and chronic stress rats, and its possible mechanism. MATERIAL AND METHODS Sprague-Dawley rats were fed with high-fat diet and subjected to chronic stress for 12 weeks, and administered orally with scutellarin for 4 weeks (n=8), and then blood and livers were harvested for analyzing. Enzyme activity assay, immunofluorescence, Western blot, and quantitative RT-PCR were performed to analyze the factors of the oxidant/antioxidant system and pathway. RESULTS After the high-fat diet and chronic stress administration for 12 weeks, serum and liver lipid metabolism of treatment groups with the different doses of SCU effectively improved and the degree of oxidative damage reduced. Using Western blot assay and immunofluorescence (IF) staining assay, Nrf2, HO-1, and PI3K, and AKT proteins significantly increased after SCU treatment for 4 weeks (P<0.01). The hepatic mRNA expression of HO-1, NQO1, and Nrf2 in SCU treatment groups was upregulated significantly through quantitative RT-PCR assay (P<0.05). However, compared to the positive control group, no difference was detected in the SCU (100 or 300 mg/kg) groups (P>0.05). These results indicate that SCU protects against NAFLD in rats via attenuation of oxidative stress. CONCLUSIONS The antioxidant effects of SCU on NAFLD are possibly dependent on PI3K/AKT activation with subsequent Nrf2 nuclear translocation, which increases expression of HO-1 and NQO1. We therefore suggest that breviscapine may be a potentially useful therapeutic strategy for NAFLD and hyperlipidemia.


Asunto(s)
Apigenina/metabolismo , Glucuronatos/metabolismo , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Animales , Antioxidantes/farmacología , Apigenina/farmacología , Dieta Alta en Grasa , Glucuronatos/farmacología , Hiperlipidemias/prevención & control , Metabolismo de los Lípidos , Hígado/metabolismo , Masculino , Factor 2 Relacionado con NF-E2/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Estrés Oxidativo/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Sprague-Dawley , Triglicéridos
19.
FEMS Microbiol Lett ; 364(22)2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-29069461

RESUMEN

The xdhR gene encodes a TetR-family regulator in Streptomyces coelicolor. However, little is known about the function of XdhR in regulating actinorhodin production. Here, we report that XdhR negatively regulates actinorhodin biosynthesis in S. coelicolor. Deletion of xdhR resulted in overproduction of actinorhodin by approximately 2.5-fold compared to the wild-type strain. Complementation of the xdhR deletion strain restored actinorhodin production to normal levels. In addition, the relative expression levels of actinorhodin cluster genes were all significantly increased in the xdhR deletion strain compared to the wild-type strain. XdhR can specifically bind the promoters of actII-4 and actII-1, two pathway-specific regulators of actinorhodin biosynthesis. These results suggest that xdhR negatively controls actinorhodin biosynthesis by directly regulating actII-4 and actII-1 in S. coelicolor.


Asunto(s)
Proteínas Bacterianas/genética , Streptomyces coelicolor/genética , Xantina Deshidrogenasa/genética , Antraquinonas/análisis , Antraquinonas/metabolismo , Proteínas Bacterianas/metabolismo , Escherichia coli/genética , Eliminación de Gen , Regulación Bacteriana de la Expresión Génica/genética , Genoma Bacteriano , Regiones Promotoras Genéticas , Unión Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Streptomyces coelicolor/metabolismo , Xantina Deshidrogenasa/metabolismo
20.
Gene ; 636: 36-41, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-28888577

RESUMEN

T cell-mediated anti-tumor immunity plays a pivotal role in cancer immune surveillance. Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is a protein receptor mainly expressed in activated T cells and regulatory T cells. CTLA-4 competes with CD28 for ligand binding and generates inhibitory signals to attenuate T cell activation. The blockade of CTLA-4 mediated immune inhibitory checkpoint has been associated with enhanced anti-tumor immunity. In this study, we use CRISPR-Cas9 system to knock out (KO) CTLA-4 from cytotoxic T lymphocytes (CTLs) and evaluate its effect on the anti-tumor activity of the CTLs. CTLA-4 KO CTLs robustly enhanced tumor cell death by 40% compared to the control and facilitated apoptosis and caspase activities in tumor cells. The knockout of CTLA-4 also increased TNF-α and IFN-γ secretion of the CTLs by approximately 2-fold. The effectiveness of CTLA-4 KO in enhancing anti-tumor activity of the CTLs was verified in vivo using mouse xenograft model. The xenografted mice treated with CTLA-4 KO CTLs demonstrated repressed tumor growth and prolonged survival compared to the control group. Our data suggest that CRISPR targeting CTLA-4 immune checkpoint could significantly improve the anti-tumor activity of CTLs.


Asunto(s)
Sistemas CRISPR-Cas , Antígeno CTLA-4/genética , Neoplasias/inmunología , Linfocitos T Citotóxicos/inmunología , Animales , Apoptosis , Antígeno CTLA-4/antagonistas & inhibidores , Caspasas/metabolismo , Células Cultivadas , Células Asesinas Inducidas por Citocinas/clasificación , Citocinas/biosíntesis , Células Dendríticas/clasificación , Células HCT116 , Humanos , Inmunofenotipificación , Ratones SCID , Neoplasias/patología , Neoplasias/terapia , Linfocitos T Citotóxicos/clasificación
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