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1.
Nucleic Acids Res ; 50(6): 3581-3592, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35323947

RESUMO

Direct cloning of biosynthetic gene clusters (BGCs) from microbial genomes facilitates natural product-based drug discovery. Here, by combining Cas12a and the advanced features of bacterial artificial chromosome library construction, we developed a fast yet efficient in vitro platform for directly capturing large BGCs, named CAT-FISHING (CRISPR/Cas12a-mediated fast direct biosynthetic gene cluster cloning). As demonstrations, several large BGCs from different actinomycetal genomic DNA samples were efficiently captured by CAT-FISHING, the largest of which was 145 kb with 75% GC content. Furthermore, the directly cloned, 110 kb long, cryptic polyketide encoding BGC from Micromonospora sp. 181 was then heterologously expressed in a Streptomyces chassis. It turned out to be a new macrolactam compound, marinolactam A, which showed promising anticancer activity. Our results indicate that CAT-FISHING is a powerful method for complicated BGC cloning, and we believe that it would be an important asset to the entire community of natural product-based drug discovery.


Assuntos
Produtos Biológicos , Streptomyces , Sistemas CRISPR-Cas , Clonagem Molecular , Família Multigênica , Streptomyces/genética
2.
Synth Syst Biotechnol ; 6(4): 335-342, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34738044

RESUMO

The versatile photosynthetic α-proteobacterium Rhodobacter sphaeroides, has recently been extensively engineered as a novel microbial cell factory (MCF) to produce pharmaceuticals, nutraceuticals, commodity chemicals and even hydrogen. However, there are no well-characterized high-activity promoters to modulate gene transcription during the engineering of R. sphaeroides. In this study, several native promoters from R. sphaeroides JDW-710 (JDW-710), an industrial strain producing high levels of co-enzyme Q10 (Q10) were selected on the basis of transcriptomic analysis. These candidate promoters were then characterized by using gusA as a reporter gene. Two native promoters, P rsp _ 7571 and P rsp _ 6124 , showed 620% and 800% higher activity, respectively, than the tac promoter, which has previously been used for gene overexpression in R. sphaeroides. In addition, a P rsp _ 7571 -derived synthetic promoter library with strengths ranging from 54% to 3200% of that of the tac promoter, was created on the basis of visualization of red fluorescent protein (RFP) expression in R. sphaeroides. Finally, as a demonstration, the synthetic pathway of Q10 was modulated by the selected promoter T334* in JDW-710; the Q10 yield in shake-flasks increased 28% and the production reached 226 mg/L. These well-characterized promoters should be highly useful in current synthetic biology platforms for refactoring the biosynthetic pathway in R. sphaeroides-derived MCFs.

3.
Chemphyschem ; 22(19): 2034-2041, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34313368

RESUMO

Molybdenum disulfide (MoS2 ) has been regarded as one of the most promising candidates for replacing Pt group noble metals as an efficient electrocatalyst to enhance the hydrogen evolution reaction (HER) in consideration of its relatively high earth abundance. Recent studies show that the catalytic efficiency of MoS2 for HER can be promoted by the presence of 1T-phase MoS2 . It is hard to precisely control the formation of 1T-MoS2 , however, due to its metastability relative to 2H-MoS2 . Elevating the stability of 1T phase allotrope is therefore of great importance and could be realized by replacing divalent S with monovalent elements or groups according to crystal field theory, which has been demonstrated through our first-principles density functional theory (DFT) calculation results. Differential Gibbs free energy analysis for hydrogen adsorption (ΔGH* ) suggest that 1T and 1T' MoSO (O doped MoS2 ) might be taken as potential candidate catalysts for HER process with better performance than 1T and 1T' MoS2 . We also propose a probable approach to synthesize 1T and 1T' MoSO under oxidation circumstance environment of graphene oxide.

4.
J Nat Prod ; 84(7): 1954-1966, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34170694

RESUMO

Cdc37 associates kinase clients to Hsp90 and promotes the development of cancers. Celastrol, a natural friedelane triterpenoid, can disrupt the Hsp90-Cdc37 interaction to provide antitumor effects. In this study, 31 new celastrol derivatives, 2a-2d, 3a-3g, and 4a-4t, were designed and synthesized, and their Hsp90-Cdc37 disruption activities and antiproliferative activities against cancer cells were evaluated. Among these compounds, 4f, with the highest tumor cell selectivity (15.4-fold), potent Hsp90-Cdc37 disruption activity (IC50 = 1.9 µM), and antiproliferative activity against MDA-MB-231 cells (IC50 = 0.2 µM), was selected as the lead compound. Further studies demonstrated 4f has strong antitumor activities both in vitro and in vivo through disrupting the Hsp90-Cdc37 interaction and inhibiting angiogenesis. In addition, 4f exhibited less toxicity than celastrol and showed a good pharmacokinetics profile in vivo. These findings suggest that 4f may be a promising candidate for development of new cancer therapies.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Chaperoninas/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Triterpenos Pentacíclicos/farmacologia , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos Nus , Simulação de Acoplamento Molecular , Estrutura Molecular , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-Zebra
5.
World J Gastroenterol ; 27(14): 1497-1506, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33911470

RESUMO

BACKGROUND: Nucleos(t)ide analogs (NAs) cessation in chronic hepatitis B (CHB) patients remains a matter of debate in clinical practice. Current guidelines recommend that patients with hepatitis B e antigen (HBeAg) seroconversion discontinue NAs after relatively long-term consolidation therapy. However, many patients fail to achieve HBeAg seroconversion after the long-term loss of HBeAg, even if hepatitis B surface antigen (HBsAg) loss occurs. It remains unclear whether NAs can be discontinued in this subset of patients. AIM: To investigate the outcomes and factors associated with HBeAg-positive CHB patients with HBeAg loss (without hepatitis B e antibody) after cessation of NAs. METHODS: We studied patients who discontinued NAs after achieving HBeAg loss. The Cox proportional hazards model was used to identify predictors for virological relapse after cessation of NAs. The cut-off value of the consolidation period was confirmed using receiver operating characteristic curves; we confirmed the cut-off value of HBsAg according to a previous study. The log-rank test was used to compare cumulative relapse rates among groups. We also studied patients with CHB who achieved HBeAg seroconversion and compared their cumulative relapse rates. Propensity score matching analysis (PSM) was used to balance baseline characteristics between the groups. RESULTS: We included 83 patients with HBeAg loss. The mean age of these patients was 32.1 ± 9.5 years, and the majority was male (67.5%). Thirty-eight patients relapsed, and the cumulative relapse rate at months 3, 6, 12, 24, 36, 60, 120, and 180 were 22.9%, 36.1%, 41.0%, 43.5%, 45.0%, 45.0%, 45.0%, and 52.8%, respectively. Twenty-six (68.4%) patients relapsed in the first 3 mo after NAs cessation, and 35 patients (92.1%) relapsed in the first year after NAs cessation. Consolidation period (≥ 24 mo vs < 24 mo) (HR 0.506, P = 0.043) and HBsAg at cessation (≥ 100 IU/mL vs < 100 IU/mL) (HR 14.869, P = 0.008) were significant predictors in multivariate Cox regression. In the PSM cohort, which included 144 patients, there were lower cumulative relapse rates in patients with HBeAg seroconversion (P = 0.036). CONCLUSION: HBeAg-positive CHB patients with HBeAg loss may be able to discontinue NAs therapy after long-term consolidation, especially in patients with HBsAg at cessation < 100 IU/mL. Careful monitoring, especially in the early stages after cessation, may ensure a favorable outcome.


Assuntos
Antígenos E da Hepatite B , Hepatite B Crônica , Adulto , Antivirais/uso terapêutico , DNA Viral/uso terapêutico , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , Humanos , Masculino , Recidiva , Soroconversão , Resultado do Tratamento , Adulto Jovem
6.
Kaohsiung J Med Sci ; 37(6): 505-512, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33559348

RESUMO

Multidrug resistance (MDR) of chemotherapy is one of the significant concerns in cancer therapy. Here in our study, cisplatin (DDP) and oleanolic acid (OA) were co-loaded in mesoporous silica nanoparticles (Nsi) to construct DDP/OA-Nsi and solve the DDP-resistance in lung cancer therapy. The cytotoxicity and apoptosis assays demonstrated that in DDP-resistant A549/DDP cells, the cytotoxicity of DDP/OA-Nsi was significantly higher than that of free DDP or DDP single delivery system (DDP-Nsi). The intracellular drug accumulation study revealed that the intracellular DDP concentration in the DDP/OA-Nsi group was also higher than that in free DDP and DDP-Nsi groups. In the A549/DDP xenograft tumor model, DDP/OA-Nsi showed the best anticancer effect. In summary, DDP/OA-Nsi was a promising drug delivery system to solve MDR in lung cancer therapy.


Assuntos
Apoptose , Cisplatino/administração & dosagem , Sistemas de Liberação de Medicamentos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/metabolismo , Nanopartículas/administração & dosagem , Ácido Oleanólico/administração & dosagem , Dióxido de Silício/química , Células A549 , Animais , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologia
7.
J Nucl Cardiol ; 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33146862

RESUMO

BACKGROUND: Pyrophosphate (PYP) scintigraphy provides high diagnostic accuracy for the detection of transthyretin (ATTR) cardiac amyloidosis (CA). There has recently been emerging interest in using 18F-sodium fluoride (NaF) for this application, yet its sensitivity has never been directly compared to that of PYP, the current molecular gold standard METHODS: Twelve subjects with ATTR-CA and 5 controls referred for PYP-SPECT were prospectively enrolled. 18F-NaF PET/CT scans were performed at 1 and 3 hours. Qualitative and quantitative analyses of the images were performed, and the sensitivity of 18F-NaF PET/CT and PYP-SPECT were compared RESULTS: Visual interpretation of NaF PET/CT yielded a sensitivity of 0.25 (95% CI 0.089 to 0.53) for the detection of ATTR-CA, which is significantly inferior to that of PYP-SPECT/CT (100%, P = .016). Visual interpretation at 3 hours yielded a similar sensitivity of 0.30 (95% CI 0.11 to 0.60, P = 1.00). There were no false-positive NaF PET studies. Mean target-to-background ratio (TBRmean) at 1h did not differ significantly (P = .21) in ATTR-CA subjects (0.83 ± 0.15) compared to controls (0.72 ± 0.15). Receiver operating characteristic (ROC) analysis yielded an area under the curve (AUC) of 0.69 ± 0.16 (95% CI 0.37 to 1.00, P = .23). CONCLUSION: With qualitative and quantitative analyses, sensitivity of NaF PET/CT is significantly inferior to that of PYP-SPECT for the diagnosis of ATTR-CA.

8.
Genet Med ; 22(8): 1338-1347, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32424177

RESUMO

PURPOSE: Genitopatellar syndrome and Say-Barber-Biesecker-Young-Simpson syndrome are caused by variants in the KAT6B gene and are part of a broad clinical spectrum called KAT6B disorders, whose variable expressivity is increasingly being recognized. METHODS: We herein present the phenotypes of 32 previously unreported individuals with a molecularly confirmed diagnosis of a KAT6B disorder, report 24 new pathogenic KAT6B variants, and review phenotypic information available on all published individuals with this condition. We also suggest a classification of clinical subtypes within the KAT6B disorder spectrum. RESULTS: We demonstrate that cerebral anomalies, optic nerve hypoplasia, neurobehavioral difficulties, and distal limb anomalies other than long thumbs and great toes, such as polydactyly, are more frequently observed than initially reported. Intestinal malrotation and its serious consequences can be present in affected individuals. Additionally, we identified four children with Pierre Robin sequence, four individuals who had increased nuchal translucency/cystic hygroma prenatally, and two fetuses with severe renal anomalies leading to renal failure. We also report an individual in which a pathogenic variant was inherited from a mildly affected parent. CONCLUSION: Our work provides a comprehensive review and expansion of the genotypic and phenotypic spectrum of KAT6B disorders that will assist clinicians in the assessment, counseling, and management of affected individuals.


Assuntos
Blefarofimose , Deficiência Intelectual , Blefarofimose/genética , Éxons , Histona Acetiltransferases/genética , Humanos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Mutação
9.
J Exp Clin Cancer Res ; 39(1): 19, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31959225

RESUMO

In the original publication of this manuscript [1], Fig. 6 contains a repeated image in error (the left image of 'Migration' and the left image of 'Invasion').

10.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3501-3508, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31621237

RESUMO

The effects of inoculation of rhizosphere-promoting bacteria (PGPR) on photosynthesis and physiological-ecological characteristics of apple tree seedlings under drought conditions were investigated in this study, aiming to provide a theoretical basis for the application of PGPR in plant drought resistance. In the pot experiment, the rhizosphere-promoting bacterium YX2 which had both ACC deaminase activity and strong phosphorus solubilizing ability was selected as the tested strain. Apple seedlings were grown under four different irrigation levels i.e., control (CK), mild drought (LD), moderate drought (MD), and severe drought (SD) with soil moisture equivalent to 70%-80%, 55%-65%, 40%-50% and 25%-35% of field water holding capacity, respectively. Inoculation of PGPR alleviated the damaging effects of drought on growth by improving relative water content and chlorophyll content in apple tree seedlings. In addition, PGPR inoculated individuals exhibited higher antioxidant enzyme activity, chlorophyll fluorescence values, stomatal conductance and photosynthetic rate and lower relative conductivity and lipid peroxidation. Our results suggested that PGPR-YX2 alleviated the negative effects of drought stress on the growth and net photosynthetic rate by improving the antioxidant system, water content and membrane functioning.


Assuntos
Secas , Malus , Fotossíntese , Plântula , Solo , Água
11.
Nat Commun ; 10(1): 3672, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31413315

RESUMO

Besides genome editing, CRISPR-Cas12a has recently been used for DNA detection applications with attomolar sensitivity but, to our knowledge, it has not been used for the detection of small molecules. Bacterial allosteric transcription factors (aTFs) have evolved to sense and respond sensitively to a variety of small molecules to benefit bacterial survival. By combining the single-stranded DNA cleavage ability of CRISPR-Cas12a and the competitive binding activities of aTFs for small molecules and double-stranded DNA, here we develop a simple, supersensitive, fast and high-throughput platform for the detection of small molecules, designated CaT-SMelor (CRISPR-Cas12a- and aTF-mediated small molecule detector). CaT-SMelor is successfully evaluated by detecting nanomolar levels of various small molecules, including uric acid and p-hydroxybenzoic acid among their structurally similar analogues. We also demonstrate that our CaT-SMelor directly measured the uric acid concentration in clinical human blood samples, indicating a great potential of CaT-SMelor in the detection of small molecules.


Assuntos
Proteínas Associadas a CRISPR , Sistemas CRISPR-Cas , Endodesoxirribonucleases , Fatores de Transcrição , Regulação Alostérica , Bioensaio , Clostridiales , Humanos , Limite de Detecção , Motivos de Nucleotídeos , Parabenos , Biologia Sintética , Ácido Úrico/sangue
12.
Front Neurosci ; 13: 584, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31258460

RESUMO

Spinal cord edema, mainly including vasogenic and cytotoxic edema, influences neurological outcome after spinal cord contusion (SCC). Aquaporin 4 (AQP4) is the most ubiquitous water channel in the central nervous system (CNS), which is a rate-limiting factor in vasogenic edema expressing in brain injury, and it contributes to the formation of cytotoxic edema locating in astrocytes. However, little is known about the regulatory mechanism of AQP4 within vasogenic and cytotoxic edema in SCC, and whether the regulation mechanism of AQP4 is related to Cytochrome coxidase (COX5A) affecting energy metabolism. Therefore, the SCC model is established by Allen's method, and the degree of edema and neuronal area is measured. The motor function of rats is evaluated by the Basso, Beattie, and Bresnahan (BBB) scoring system. Meanwhile, AQP4 and COX5A are detected by real-time quantitative PCR (qRT-PCR) and western blot (WB). The localization of targeted protein is exhibited by immunohistochemical staining (IHC) and immunofluorescence (IF). Additionally, the methodology of AQP4 lentivirus-mediated RNA interference (AQP4-RNAi) is used to reveal the effect on edema of SCC and the regulating molecular mechanism. Firstly, we observe that the tissue water content increases after SCC and decreases after the peak value of tissue water content at 3 days (P < 0.05) with abundant expression of AQP4 protein locating around vascular endothelial cells (VECs), which suggests that the increasing AQP4 promotes water reabsorption and improves vasogenic edema in the early stage of SCC. However, the neuronal area is larger than in the sham group in the 7 days (P < 0.05) with the total water content of spinal cord decrease. Meanwhile, AQP4 migrates from VECs to neuronal cytomembrane, which indicates that AQP4 plays a crucial role in aggravating the formation and development of cytotoxic edema in the middle stages of SCC. Secondly, AQP4-RNAi is used to elucidate the mechanism of AQP4 to edema of SCC. The neuronal area shrinks and the area of cytotoxic edema reduces after AQP4 downregulation. The BBB scores are significantly higher than in the vector group after AQP4-RNAi at 5, 7, and 14 (P < 0.05). There is a relationship between AQP4 and COX5A shown by bioinformatics analysis. After AQP4 inhibition, the expression of COX5A is significantly upregulated in the swelling astrocytes. Therefore, the inhibition of AQP4 expression reduces cytotoxic edema in SCC and improves motor function, which may be associated with upregulation of COX5A via affecting energy metabolism. Moreover, it is not clear how the inhibition of AQP4 directly causes the upregulation of COX5A.

13.
Huan Jing Ke Xue ; 40(4): 1529-1536, 2019 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087892

RESUMO

Mass concentration, seasonal variation and sources of organic carbon (OC), element carbon (EC), methanol-soluble organic carbon (MSOC), and seven carbon components (OC1-4, EC1-3) were detected by thermal-optical analysis of 353 PM2.5 samples in Xi'an in 2017. The results show that the average mass concentrations of OC, EC, and MSOC were (17.56±11.83), (4.08±2.95) and (11.10±6.77) µg·m-3, respectively. The seasonal trend of the OC concentration follows the order winter > spring > summer > autumn. The seasonal trend in EC concentration follows the order winter > spring≈autumn > summer. The average MSOC/OC value is 0.64±0.20. The highest value is observed in winter and the lowest in summer. The correlation between OC and EC is good in spring (r2=0.76), but the correlation is poor in winter (r2=0.43). These results indicate that the source of the carbon aerosols was different. The content of secondary organic aerosols was estimated by the EC tracing method. The average mass concentration of SOC accounted for 51.9%, 38.4%, 37.3% and 44.0% of OC in spring, summer, autumn, and winter, respectively. The main sources of carbonaceous aerosols were analyzed by principal component analysis. The results show that carbonaceous aerosols originate mainly from coal and vehicle emissions in Xi'an.

14.
Am J Chin Med ; 47(3): 595-612, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31122040

RESUMO

Although Astragalus polysaccharide (APS) has been shown to have various pharmacological effects, there have been no studies concerning the inhibitory effects of APS on the radiation-induced bystander effects (RIBE). The aim of this study was to investigate whether APS could suppress RIBE damage by inhibiting cell growth, micronucleus (MN) formation and 53BP1 foci number increased in bone marrow mesenchymal stem cells (BMSCs), named bystander cells, as well as to explore its mechanism. In this study, APS decreased proliferation and colony rate of bystander cells by inducing cell cycle arrest at G1 phase via extrinsic and intrinsic DNA damage. Regarding mechanism, APS inhibited mitogen-activated protein kinase (MAPK) signal pathway by down-regulating the expression of the key proteins, phosphorylated JNK (p-JNK), phosphorylated ERK (p-ERK) but not phosphorylated P38 (p-P38), and down-regulating their downstream function protein and molecule, cyclooxygenase-2 (COX-2) and reactive oxygen species (ROS). Moreover, in bystander cells, APS inhibits expression of transforming growth factor ß receptor II (TGF- ß R II), a cell membrane receptor, resulting in lower ROS production and secretion via TGF- ß R-JNK/ERK-COX-2/ROS not P38 signaling. They gave a hint that the decreased RIBE damage induced by APS treatment involved TGF- ß R-JNK/ERK-COX-2/ROS down-regulation.


Assuntos
Astrágalo (Planta)/química , Efeito Espectador/efeitos dos fármacos , Carbono , Proliferação de Células/efeitos dos fármacos , Fase G1/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos da radiação , Polissacarídeos/farmacologia , Células Cultivadas , Ciclo-Oxigenase 2 , Dano ao DNA , Humanos , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Fator de Crescimento Transformador beta/metabolismo
15.
Inorg Chem ; 58(3): 1746-1749, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30666862

RESUMO

The cationic [Pb4(OH)4]4+ cubane as a template was first introduced to the 3D iodocuprate network, which is fabricated from the alternative connection of infinite [Cu2I2] n chains and µ2-I linkers. Distinct from most of the photocatalysts with UV or visible light for the photocatalytic degradation of an organic pollutant, the target compound could accomplish this task under direct sunlight because of the introduction of photoactive species. Our work provides a promising strategy to generate superior photocatalysts via the encapsulation of photoactive units into open frameworks.

16.
Eur J Med Chem ; 162: 348-363, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30448420

RESUMO

Accetohydroxyacid synthase (AHAS) is the first enzyme involved in the biosynthetic pathway of branched-chain amino acids. Earlier gene mutation of Candida albicans in a mouse model suggested that this enzyme is a promising target of antifungals. Recent studies have demonstrated that some commercial AHAS-inhibiting sulfonylurea herbicides exerted desirable antifungal activity. In this study, we have designed and synthesized 68 novel ethoxysulfulron (ES) derivatives and evaluated their inhibition constants (Ki) against C. albicans AHAS and cell based minimum inhibitory concentration (MIC) values. The target compounds 5-1, 5-10, 5-22, 5-31 and 5-37 displayed stronger AHAS inhibitions than ES did. Compound 5-1 had the best Ki of 6.7 nM against fungal AHAS and MIC values of 2.5 mg/L against Candida albicans and Candica parapsilosis after 72 h. A suitable nematode model was established here and the antifungal activity of 5-1 was further evaluated in vivo. A possible binding mode was simulated via molecular docking and a comparative field analysis (CoMFA) model was constructed to understand the structure-activity relationship. The current study has indicated that some ES derivatives should be considered as promising hits to develop antifungal drugs with novel biological target.


Assuntos
Acetolactato Sintase/antagonistas & inibidores , Antifúngicos/química , Relação Quantitativa Estrutura-Atividade , Compostos de Sulfonilureia/farmacologia , Animais , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Herbicidas , Camundongos , Simulação de Acoplamento Molecular , Nematoides/efeitos dos fármacos , Compostos de Sulfonilureia/química
17.
Synth Syst Biotechnol ; 4(4): 212-219, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31890925

RESUMO

Coenzyme Q10 (CoQ10) is an important component of the respiratory chain in humans and some bacteria. As a high-value-added nutraceutical antioxidant, CoQ10 has excellent capacity to prevent cardiovascular disease. The content of CoQ10 in the industrial Rhodobacter sphaeroides HY01 is hundreds of folds higher than normal physiological levels. In this study, we found that overexpression or optimization of the synthetic pathway failed CoQ10 overproduction in the HY01 strain. Moreover, under phosphate- limited conditions (decreased phosphate or in the absence of inorganic phosphate addition), CoQ10 production increased significantly by 12% to220 mg/L, biomass decreased by 12%, and the CoQ10 productivity of unit cells increased by 27%. In subsequent fed-batch fermentation, CoQ10 production reached 272 mg/L in the shake-flask fermentation and 1.95 g/L in a 100-L bioreactor under phosphate limitation. Furthermore, to understand the mechanism associated with CoQ10 overproduction under phosphate- limited conditions, the comparatve transcriptome analysis was performed. These results indicated that phosphate limitation combined with glucose fed-batch fermentation represented an effective strategy for CoQ10 production in the HY01. Phosphate limitation induced a pleiotropic effect on cell metabolism, and that improved CoQ10 biosynthesis efficiency was possibly related to the disturbance of energy metabolism and redox potential.

18.
Neural Regen Res ; 14(2): 354-360, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30531020

RESUMO

The main goal of spinal cord rehabilitation is to restore walking ability and improve walking quality after spinal cord injury (SCI). The spatiotemporal parameters of walking and the parameters of plantar pressure can be obtained using a plantar pressure analysis system. Previous studies have reported step asymmetry in patients with bilateral SCI. However, the asymmetry of other parameters in patients with SCI has not been reported. This was a prospective, cross-sectional study, which included 23 patients with SCI, aged 48.1 ± 14.5 years, and 28 healthy subjects, aged 47.1 ± 9.8 years. All subjects underwent bare foot walking on a plantar pressure measurement device to measure walking speed and spatiotemporal parameters. Compared with healthy subjects, SCI patients had slower walking speed, longer stride time and stance time, larger stance phase percentage, and shorter stride length. The peak pressures under the metatarsal heads and toe were lower in SCI patients than in healthy subjects. In the heel, regional impulse and the contact area percentage in SCI patients were higher than those in healthy subjects. The symmetry indexes of stance time, step length, maximum force, impulse and contact area were increased in SCI patients, indicating a decline in symmetry. The results confirm that the gait quality, including spatiotemporal variables and plantar pressure parameters, and symmetry index were lower in SCI patients compared with healthy subjects. Plantar pressure parameters and symmetry index could be sensitive quantitative parameters to improve gait quality of SCI patients. The protocols were approved by the Clinical Research Ethics Committee of Shengjing Hospital of China Medical University (approval No. 2015PS54J) on August 13, 2015. This trial was registered in the ISRCTN Registry (ISRCTN42544587) on August 22, 2018. Protocol version: 1.0.

19.
J Exp Clin Cancer Res ; 37(1): 301, 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30514328

RESUMO

BACKGROUND: Esophageal cancer is a high incident cancer worldwide with poor survival and limited therapeutic options. Alterations of microRNAs are common in cancers, and many of these micro RNAs are potential therapeutic and diagnostic targets to treat these cancers. miR-10b-3p located in chromosome region 2q31.1, and its expression is frequently increased in esophageal squamous cell carcinoma (ESCC). However, the biological functions, clinical significance and therapeutic implications of miR-10b-3p in ESCC remain unclear. METHODS: The expression levels of miR-10b-3p in ESCC specimens were analyzed by in situ hybridization (ISH) and quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays. Ectopic overexpression of miR-10b-3p in ESCC cells, mouse xenograft model, and metastasis model were used to evaluate the effects of miR-10b-3p on proliferation, and migration of cancer cells. Luciferase reporter assay and Western blot were performed to validate the potential targets of miR-10b-3p after the preliminary screening by computer-aided microarray analysis. RESULTS: We found that miR-10b-3p expression levels were significantly upregulated in the tumor tissues and serum samples of patients with ESCC. The expression levels of miR-10b-3p in both tumor tissues and serum samples were inversely associated with lymph node metastasis and clinical stages. We identified the expression level of miR-10b-3p in ESCC cancer samples as an independent prognostic marker of the overall survival rates of ESCC patients. We found more frequent hypomethylation of the CpG sites located upstream of the miR-10b-3p gene in the ESCC tissues compared with in the adjacent normal tissues, and the DNA methylation status of miR-10b-3p promoter region inversely correlated with the expression levels of miR-10b-3p. Ectopic overexpression of miR-10b-3p promoted cell proliferation, colony formation, migration and invasion in ESCC. While knockdown of miR-10b-3p had the opposite effects, particularly in promoting apoptosis. Mouse xenograft model confirmed that miR-10b-3p functions as a potent oncogenic miRNA in ESCC, which also promoting ESCC metastasis. Mechanistically, we found miR-10b-3p regulated FOXO3 expression by directly binding to the 3'-untranslated region. And systemic delivery of miR-10b-3p antagomir reduced tumor growth and inhibit FOXO3 protein expression in nude mice. CONCLUSIONS: Collectively, our findings suggested upregulated expression of miR-10b-3p caused by promoter hypomethylation contributed to the progression of ESCC; Thus, miR-10b-3p is a potentially effective biomarker for ESCC that could have further therapeutic implications.


Assuntos
Metilação de DNA , Carcinoma de Células Escamosas do Esôfago/genética , Proteína Forkhead Box O3/genética , MicroRNAs/genética , Animais , Linhagem Celular Tumoral , Cromossomos Humanos Par 2 , Modelos Animais de Doenças , Progressão da Doença , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Humanos , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Regiões Promotoras Genéticas , Transfecção , Regulação para Cima
20.
Yi Chuan ; 40(10): 888-899, 2018 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-30369471

RESUMO

Avermectins, are pesticides of fermentation products with high efficacy and low toxicity and play important roles in food and agricultural product safety, animal and human health. Ivermectins, the derivatives of avermectins, are used to treat Onchocerciasis, also known as River Blindness. Thanks to these discoveries, more than 200 million Africans are lucky to be exempted from blindness. Great efforts have been made on better understanding of the microbial production system of avermectins through genetic engineering in China. Starting from scratch, Chinese avermectin industry has experienced a comprehensive technological innovation with significantly improved yield, titer and productivity of avermectins, and became the exclusive supplier for the global market. The success of avermectin industry innovation in China not only shed lights on the intelligent yield improvement of other microbial natural product drugs, but also gained wide international recognition. We provide here an overview of the discovery and development of basic and applied research of avermectins, especially historical evolution of avermectins made in China, which will benefit industrial development of microbial drugs in China.


Assuntos
Anti-Helmínticos/metabolismo , Bactérias/genética , Bactérias/metabolismo , Ivermectina/análogos & derivados , Animais , Anti-Helmínticos/química , China , Engenharia Genética , Humanos , Microbiologia Industrial , Ivermectina/química , Ivermectina/metabolismo
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