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2.
Artigo em Inglês | MEDLINE | ID: mdl-31583448

RESUMO

Corynebacterium glutamicum is a versatile workhorse for producing industrially important commodities. The design of an optimal strain often requires the manipulation of metabolic and regulatory genes to different levels, such as overexpression, downregulation, and deletion. Unfortunately, few tools to achieve multiple functions simultaneously have been reported. Here, a dual-functional clustered regularly interspaced short palindromic repeats (CRISPR) (RE-CRISPR) system that combined genome editing and transcriptional repression was designed using a catalytically active Cas12a (a.k.a. Cpf1) in C. glutamicum. Firstly, gene deletion was achieved using Cas12a under a constitutive promoter. Then, via engineering of the guide RNA sequences, transcriptional repression was successfully achieved using a catalytically active Cas12a with crRNAs containing 15 or 16 bp spacer sequences, whose gene repression efficiency was comparable to that of the canonical system (deactivated Cas12a with full-length crRNAs). Finally, RE-CRISPR was developed to achieve genome editing and transcriptional repression simultaneously by transforming a single crRNA plasmid and Cas12a plasmid. The application of RE-CRISPR was demonstrated to increase the production of cysteine and serine for ~ 3.7-fold and 2.5-fold, respectively, in a single step. This study expands the application of CRISPR/Cas12a-based genome engineering and provides a powerful synthetic biology tool for multiplex metabolic engineering of C. glutamicum.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31487116

RESUMO

A synergistic N doping plus PO4 3- intercalation strategy is used to induce high conversion (ca. 41 %) of 2H-MoS2 into 1T-MoS2 , which is much higher than single N doping (ca. 28 %) or single PO4 3- intercalation (ca. 10 %). A scattering mechanism is proposed to illustrate the synergistic phase transformation from the 2H to the 1T phase, which was confirmed by synchrotron radiation and spherical aberration TEM. To further enhance reaction kinetics, the designed (N,PO4 3- )-MoS2 nanosheets are combined with conductive vertical graphene (VG) skeleton forming binder-free arrays for high-efficiency hydrogen evolution reaction (HER). Owing to the decreased band gap, lower d-band center, and smaller hydrogen adsorption/desorption energy, the designed (N,PO4 3- )-MoS2 /VG electrode shows excellent HER performance with a lower Tafel slope and overpotential than N-MoS2 /VG, PO4 3- -MoS2 /VG counterparts, and other Mo-base catalysts in the literature.

4.
Free Radic Biol Med ; 143: 441-453, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31493504

RESUMO

BACKGROUND: Oxidative stress and neuronal apoptosis play important roles in the pathogenesis of early brain injury (EBI) after subarachnoid hemorrhage (SAH). The activation of TGR5, a novel membrane-bound bile acid receptor, possesses anti-oxidative stress and anti-apoptotic effects in hepatobiliary disease and kidney disease. The present study aimed to explore the neuroprotective effect of TGR5 activation against EBI after SAH and the potential underlying mechanisms. METHODS: The endovascular perforation model of SAH was performed on 199 Sprague Dawley rats to investigate the beneficial effects of TGR5 activation after SAH. INT-777, a specific synthetic TGR5 agonist, was administered intranasally at 1 h after SAH induction. TGR5 CRISPR and ALDH2 CRISPR were administered intracerebroventricularly at 48 h before SAH to illuminate potential mechanisms. The SAH grade, short-term and long-term neurobehavioral tests, TUNEL staining, Fluoro-Jade C staining, Nissl staining, immunofluorescence staining, and western blots were performed at 24 h after SAH. RESULTS: The expressions of endogenous TGR5 and ALDH2 gradually increased and peaked at 24 h after SAH. TGR5 was expressed primarily in neurons, as well as in astrocytes and microglia. The activation of TGR5 with INT-777 significantly improved the short-term and long-term neurological deficits, accompanied by reduced the oxidative stress and neuronal apoptosis at 24 h after SAH. Moreover, INT-777 treatment significantly increased the expressions of TGR5, cAMP, phosphorylated PKCε, ALDH2, HO-1, and Bcl-2, while downregulated the expressions of 4-HNE, Bax, and Cleaved Caspase-3. TGR5 CRISPR and ALDH2 CRISPR abolished the neuroprotective effects of TGR5 activation after SAH. CONCLUSIONS: In summary, the activation of TGR5 with INT-777 attenuated oxidative stress and neuronal apoptosis via the cAMP/PKCε/ALDH2 signaling pathway after SAH in rats. Furthermore, TGR5 may serve as a novel therapeutic target to ameliorate EBI after SAH.

5.
Immunology ; 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31557322

RESUMO

Reagents that activate the signaling adaptor Stimulator of Interferon Genes (STING) suppress experimentally induced autoimmunity in murine models of multiple sclerosis and arthritis. In this study, we evaluated STING agonists as potential reagents to inhibit spontaneous autoimmune Type I Diabetes (T1D) onset in NOD female mice. Treatments with DNA nanoparticles (DNPs), which activate STING when cargo DNA is sensed, delayed T1D onset and reduced T1D incidence when administered before T1D onset. DNP treatment elevated indoleamine 2,3 dioxygenase (IDO) activity, which regulates T cell immunity, in spleen, pancreatic lymph nodes and pancreas of NOD mice. Therapeutic responses to DNPs were partially reversed by inhibiting IDO and DNP treatment synergized with insulin therapy to further delay T1D onset and reduce T1D incidence. Treating pre-diabetic NOD mice with cyclic guanyl-adenyl dinucleotide (cGAMP) to activate STING directly delayed T1D onset and stimulated IFNαß, while treatment with cyclic diguanyl nucleotide (cdiGMP) did not delay T1D onset or induce IFNαß in NOD mice. DNA sequence analyses revealed that NOD mice possess a STING polymorphism that may explain differential responses to cGAMP and cdiGMP. In summary, STING agonists attenuate T1D progression and DNPs enhance therapeutic responses to insulin therapy.

6.
J Environ Manage ; 250: 109491, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31521034

RESUMO

Carbon source and influent COD/N (chemical oxygen demand: total nitrogen) pose distinct effects on nitrogen removal efficiency and microbial community structure of constructed wetlands. To investigate the interactive effect of carbon source with COD/N on nitrogen removal and microbial community structure in subsurface flow constructed wetlands, glucose (C6H12O6) and sodium acetate (C2H3NaO2) were used to determine five COD/N ratios in nine groups of constructed wetlands divided into glucose constructed wetlands and sodium acetate constructed wetlands. Results showed that efficiency in COD removal increased with COD/N, and peak value reached 92.7%. Interactive effect of carbon source with COD/N on system pH and ammonium removal was notably significant. Differences in ammonium removal performance between treatments were achieved by the variation of influent COD/N ratio and the change of system pH resulted from different carbon sources, and the result suggested that glucose was a better choice at high COD/N ratio. System microbial community structure was significantly affected by carbon source, influent COD/N ratio and their interaction. Microbial biomass in constructed wetlands significantly increased with increasing COD/N ratio. Higher density and diversity of fungus were observed in glucose constructed wetlands, particularly at COD/N ratio of 7 and 10.

7.
Clin Epigenetics ; 11(1): 133, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31506096

RESUMO

BACKGROUND: Studies demonstrate the impact of diet and physical activity on epigenetic biomarkers, specifically DNA methylation. However, no intervention studies have examined the combined impact of dietary and activity changes on the blood epigenome. The objective of this study was to examine the impact of the Make Better Choices 2 (MBC2) healthy diet and activity intervention on patterns of epigenome-wide DNA methylation. The MBC2 study was a 9-month randomized controlled trial among adults aged 18-65 with non-optimal levels of health behaviors. The study compared three 12-week interventions to (1) simultaneously increase exercise and fruit/vegetable intake, while decreasing sedentary leisure screen time; (2) sequentially increase fruit/vegetable intake and decrease leisure screen time first, then increase exercise; (3) increase sleep and decrease stress (control). We collected blood samples at baseline, 3 and 9 months, and measured DNA methylation using the Illumina EPIC (850 k) BeadChip. We examined region-based differential methylation patterns using linear regression models with the false discovery rate of 0.05. We also conducted pathway analysis using gene ontology (GO), KEGG, and IPA canonical pathway databases. RESULTS: We found no differences between the MBC2 population (n = 340) and the subsample with DNA methylation measured (n = 68) on baseline characteristics or the impact of the intervention on behavior change. We identified no differentially methylated regions at baseline between the control versus intervention groups. At 3 versus 9 months, we identified 154 and 298 differentially methylated regions, respectively, between controls compared to pooled samples from sequential and simultaneous groups. In the GO database, we identified two gene ontology terms related to hemophilic cell adhesion and cell-cell adhesion. In IPA analysis, we found pathways related to carcinogenesis including PI3K/AKT, Wnt/ß-catenin, sonic hedgehog, and p53 signaling. We observed an overlap between 3 and 9 months, including the GDP-L-fucose biosynthesis I, methylmalonyl metabolism, and estrogen-mediated cell cycle regulation pathways. CONCLUSIONS: The results demonstrate that the MBC2 diet and physical activity intervention impacts patterns of DNA methylation in gene regions related to cell cycle regulation and carcinogenesis. Future studies will examine DNA methylation as a biomarker to identify populations that may particularly benefit from incorporating health behavior change into plans for precision prevention.

8.
Med Sci Monit ; 25: 6711-6718, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31492830

RESUMO

BACKGROUND Liver cancer is one of the most common malignancies around the world and one of the major causes of cancer related mortality. The objective of this study was to evaluate the anticancer effect of the natural compound psilostachyin-A on 5-fluorouracil-resistant human liver carcinoma cells and its effects on autophagy, cell cycle, caspase activation, and the ERK/MAPK signaling pathway. MATERIAL AND METHODS Cell Counting Kit 8 (CCK-8) assay was used to evaluate the effects on HepG2 cell viability at different doses of psilostachyin-A. Cell cycle analysis was performed using flow cytometry, and Transwell assay was used to check effects on cell invasion. Transmission electron microscopic studies were done to evaluate autophagy induced by psilostachyin-A, and the western blot method was carried out to evaluate the effects on autophagy and the ERK/MAPK signaling pathway. RESULTS CCK-8 assay revealed that the psilostachyin-A reduced the cell viability of HepG2 cancer cells in a dose dependent manner. Psilostachyin-A also reduced the colony forming potential of HepG2 cells, concentration dependently. The IC50 of psilostachyin was found to be 25 µM. The anticancer effects of psilostachyin-A were due to the induction of autophagy which was accompanied by enhancement of LC3B II expression. Psilostachyin also caused cell cycle arrest by enhancing the accumulation of HepG2 cells in the G2/M phase. Transwell assay showed that psilostachyin-A suppressed the invasion of HepG2 cells. The results also showed that psilostachyin-A could block the ERK/MAPK pathway, indicative of the cytotoxic effects of psilostachyin-A on liver cancer. CONCLUSIONS These preliminary observations suggested that psilostachyin-A might prove beneficial in the treatment of liver cancer.

9.
Int Wound J ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31489774

RESUMO

This study aimed to systematically review and identify the risk factors for the recurrence of diabetic foot ulcers (DFUs) among diabetic patients. PUBMED, EMBASE, Web of Science, Cochrane Library, China Biology Medicine (CBM), China National Knowledge Infrastructure (CNKI), WanFang, and VIP databases were electronically searched to identify eligible studies updated to January 2019 to collect case-control studies or cohort studies on the risk factors for the recurrence of DFUs. Two reviewers independently screened the literature, extracted data, and assessed the risk of bias of included studies using the Newcastle-Ottawa Scale. A meta-analysis was performed using RevMan 5.3. Nine retrospective cohort studies were included, in which 1426 patients were enrolled, 542 in the DFU recurrence group and 884 in the non-recurrent DFU group. Risk factors for the recurrence of DFUs included male gender (odds ratio [OR] = 1.38, 95% confidence interval [CI], 1.07-1.78, P < .05), smoking (OR = 1.66, 95% CI, 1.26-2.20, P = .0004), duration of diabetes (OR = 4.43, 95% CI, 1.96-6.90, P = .0004), duration of past DFUs (OR = 1.02, 95% CI, 1.00-1.03, P = .006), plantar ulcers (OR = 5.31, 95% CI, 4.93-5.72, P <.00001), peripheral artery disease (OR = 1.65, 95% CI, 1.20-2.28, P = .002), and diabetic peripheral neuropathy (OR = 2.15, 95% CI, 1.40-3.30, P = .0005). No significant differences were found in age, body mass index, total cholesterol, diabetic nephropathy, diabetic retinopathy, or hypertension. Health care staff should pay attention to the identified risk factors for the recurrence of DFUs. Because of the limited quality and quantity of the included studies, rigorous studies with adequate sample sizes are needed to verify the conclusion.

10.
Clin Cancer Res ; 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31471311

RESUMO

PURPOSE: We recently reported that indoleamine 2, 3-dioxygenase (IDO) activity is inversely related to distant metastasis risk and survival in stage III non-small cell lung cancer (NSCLC). The present study examined whether radiotherapy (RT) dose fractionation correlates with IDO-mediated immune activity in patients with early-stage NSCLC. METHODS: Patients with newly diagnosed stage I-II NSCLC treated with either conventionally fractionated 3-dimensional conformal radiotherapy (3DCRT) or stereotactic body radiotherapy (SBRT) were analyzed. Levels of two key molecules associated with the IDO immune checkpoint, serum kynurenine and the kynurenine:tryptophan ratio (K:T ratio), were measured at pre-RT, during-RT, and 3-month post-RT. The relationship between disease control outcomes [overall survival (OS), progression free survival, and local/regional/distant failure rates] and absolute levels of these markers, as well as dynamic changes in their levels during RT, was studied. RESULTS: Fifty-six patients (SBRT=28, 3DCRT=28) with early stage NSCLC were studied. In all patients, higher kynurenine post-RT was significantly associated with worse OS (HR, 1.25, 95% CI 1.01-1.55, P=0.044). No statistically significant differences in absolute kynurenine levels or the K:T ratio were observed in patients treated with 3DCRT or SBRT at any of the three time points. However, the absolute kynurenine levels rose significantly post-RT in the 3DCRT patients with the median increase (0.721 ng/mL), whereas SBRT patients did not (0.115 ng/mL); P=0.022. CONCLUSIONS: This study validated that elevated IDO activity correlated with worse survival outcomes in patients with early-stage NSCLC treated with definitive RT. Hypofractionated SBRT may have less immune suppressive effect than 3DCRT, as measured by IDO.

11.
Opt Express ; 27(14): 19503-19519, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31503708

RESUMO

A shear-joint deformable mirror (DM) is important in the high-power laser systems such as the National Ignition Facility (NIF). In this paper, the print-through high-frequency aberration (PT-HIFA) that arises from adhesive curing and is corresponding to the actuator array is reported to exist in the initial surface shape of a lab-made shear-joint NIF DM. Meanwhile, experimental results show that the PT-HIFA has a great modulation on the laser intensity. This PT-HIFA could not be corrected effectively by the DM and may result in dangerous damage in the high power laser systems. In order to eliminate the PT-HIFA, we investigate the influence of the structural parameters on the PT-HIFA in a shear-joint DM through simulation and experiment. Simulational results show that the structural parameters have different influences on the PT-HIFA. In the experiment, by optimizing the structural parameters, the PT-HIFA could be eliminated in the shear-joint NIF DM and the modulation effect on the laser intensity could be removed. This investigation could help other researchers to determine appropriate structural parameters and to achieve a fine surface shape in their own shear-joint DMs.

12.
Opt Express ; 27(18): 25205-25227, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31510397

RESUMO

The annular laser beam (ALB) is widely used in many fields, which could be affected by laser power and beam quality. To effectively and flexibly improve the beam quality of high-power large-aperture thin-wall ALB, a two-stage enlargement and adaptive correction configuration (TEACC) consisting of a novel outer-surface tubular deformable mirror (OTDM) and two extra prism groups (EPGs) is proposed in this paper. The correction principle and design principle of the TEACC are derived and analyzed. Based on the principle, a typical OTDM prototype and EPG structure are designed. Annular aberrations are compensated by applying the OTDM's influence functions and the least-square algorithm in simulation. The results show that the TEACC could perfectly compensate the wavefront distortions described by the 2nd to 36th order Zernike annular aberrations.

13.
Med Gas Res ; 9(3): 122-126, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31552874

RESUMO

Cognitive deficits are a devastating neurological outcome seen in survivors of cardiac arrest. We previously reported water electrolysis derived 67% hydrogen gas inhalation has some beneficial effects on short-term outcomes in a rat model of global brain hypoxia-ischemia induced by asphyxia cardiac arrest. In the present study, we further investigated its protective effects in long-term spatial learning memory function using the same animal model. Water electrolysis derived 67% hydrogen gas was either administered 1 hour prior to cardiac arrest for 1 hour and at 1-hour post-resuscitation for 1 hour (pre- & post-treatment) or at 1-hour post-resuscitation for 2 hours (post-treatment). T-maze and Morris water maze were used for hippocampal memory function evaluation at 7 and 14 days post-resuscitation, respectively. Neuronal degeneration within hippocampal Cornu Ammonis 1 (CA1) regions was examined by Fluoro-Jade staining ex vivo. Hippocampal deficits were detected at 7 and 18 days post-resuscitation, with increased neuronal degeneration within hippocampal CA1 regions. Both hydrogen gas treatment regimens significantly improved spatial learning function and attenuated neuronal degeneration within hippocampal CA1 regions at 18 days post-resuscitation. Our findings suggest that water electrolysis derived 67% hydrogen gas may be an effective therapeutic approach for improving cognitive outcomes associated with global brain hypoxia-ischemia following cardiac arrest. The study was approved by the Animal Health and Safety Committees of Loma Linda University, USA (approval number: IACUC #8170006) on March 2, 2017.

14.
Biotechnol Bioeng ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31478186

RESUMO

S-Adenosyl-l-methionine (SAM) is an important small molecule compound widely used in treating various diseases. Although l-methionine is generally used, the low-cost dl-methionine is more suitable as the substrate for industrial production of SAM. However, d-methionine is inefficient for SAM formation due to the substrate-specificity of SAM synthetase. In order to increase the utilization efficiency of dl-methionine, intracellular conversion of d-methionine to l-methionine was investigated in the type strain Saccharomyces cerevisiae BY4741 and an industrial strain S. cerevisiae HDL. Firstly, via disruption of HPA3 encoding d-amino acid-N-acetyltransferase, d-methionine was accumulated in vivo and no N-acetyl-d-methionine production was observed. Further, codon-optimized d-amino acid oxidase (DAAO) gene from Trigonopsis variabilis (Genbank MK280686) and l-phenylalanine dehydrogenase gene (l-PheDH) from Rhodococcus jostii (Genbank MK280687) were introduced to convert d-methionine to l-methionine, SAM concentration and content was increased by 110% and 72.1% in BY4741 (plasmid borne) and increased by 38.2% and 34.1% in HDL (genome integrated), by feeding 0.5 g/L d-methionine. Using the recently developed CRISPR tools, the DAAO and l-PheDH expression cassettes were integrated into the HPA3 and SAH1 loci while SAM2 expression was integrated into the SPE2 and GLC3 loci of HDL, and the resultant strain HDL-R2 accumulated 289% and 192% more SAM concentration and content, respectively, by feeding 0.5 g/L dl-methionine. Further, in a 10 L fed-batch fermentation process, 10.3 g/L SAM were accumulated with the SAM content of 242 mg/g dry cell weight by feeding 16 g/L dl-methionine. The strategies used here provided a promising approach to enhance SAM production using low-cost dl-methionine.

15.
Front Immunol ; 10: 2017, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31555267

RESUMO

B6.Nba2 mice spontaneously develop a lupus-like disease characterized by elevated levels of serum anti-nuclear autoantibody (ANA) immune complexes and constitutive type I interferon (IFNα) production. During disease progression, both plasmacytoid dendritic cells (pDCs) and antibody secreting plasma cells accumulate in spleens of B6.Nba2 mice. Indoleamine 2,3-dioxygenase (IDO) has been suggested to play a role in several autoimmune diseases including in the MRL/lpr model of mouse lupus-like disease; however, it remains unknown if IDO is involved in disease development and/or progression in other spontaneous models. We show here that IDO1 protein and total IDO enzymatic activity are significantly elevated in lupus-prone B6.Nba2 mice relative to B6 controls. IDO1 expression was restricted to PCs and SignR1+ macrophages in both strains, while significantly increased in B6.Nba2-derived SiglecH+ (SigH+) pDCs. Despite this unique expression pattern, neither pharmacologic inhibition of total IDO nor IDO1 gene ablation altered serum autoantibody levels, splenic immune cell activation pattern, or renal inflammation in B6.Nba2 mice. Interestingly, IDO pharmacologic inhibition, but not IDO1 deficiency, resulted in diminished complement factor C'3 fixation to kidney glomeruli, suggesting a possible therapeutic benefit of IDO inhibition in SLE patients with renal involvement.

16.
Curr Opin Plant Biol ; 52: 106-113, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31546132

RESUMO

The regulated dynamic transport of materials among organelles through endomembrane trafficking pathways is essential for plant growth, development, and environmental adaptation, and thus is a major topic of plant biology research. Large-scale chemical library screens have identified small molecules that could potentially inhibit different plant endomembrane trafficking steps. Further characterization of these molecules has provided valuable tools for understanding plant endomembrane trafficking and uncovered novel regulators of trafficking processes.

17.
Adv Mater ; 31(40): e1902900, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31408234

RESUMO

Although in situ restoration of blood supply to the infarction region and attenuating pre-existing extracellular matrix degradation remain potential therapeutic approaches for myocardial infarction (MI), local delivery of therapeutics has been limited by low accumulation (inefficacy) and unnecessary diffusion (toxicity). Here, a dual functional MI-responsive hydrogel is fabricated for on-demand drug delivery to promote angiogenesis and inhibit cardiac remodeling by targeting upregulated matrix metalloproteinase-2/9 (MMP-2/9) after MI. A glutathione (GSH)-modified collagen hydrogel (collagen-GSH) is prepared by conjugating collagen amine groups with GSH sulfhydryl groups and the recombinant protein GST-TIMP-bFGF (bFGF: basic fibroblast growth factor) by fusing bFGF with glutathione-S-transferase (GST) and MMP-2/9 cleavable peptide PLGLAG (TIMP). Specific binding between GST and GSH significantly improves the amount of GST-TIMP-bFGF loaded in collagen-GSH hydrogel. The TIMP peptide enclosed between GST and bFGF responds to MMPs for on-demand release during MI. Additionally, the TIMP peptide is a competitive substrate of MMPs that inhibits the excessive degradation of cardiac matrix by MMPs after MI. GST-TIMP-bFGF/collagen-GSH hydrogels promote the recovery of MI rats by enhancing vascularization and ameliorating myocardium remodeling. The results suggest that on-demand growth factor delivery by synchronously controlling binding and responsive release to promote angiogenesis and attenuate cardiac remodeling might be promising for the treatment of ischemic heart disease.

18.
Genet Test Mol Biomarkers ; 23(9): 610-617, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31368816

RESUMO

Aims: This study was designed to investigate differentially expressed genes (DEGs) in the annulus fibrosus (AF), nucleus pulposus (NP), and whole blood (WB) of intervertebral disk degeneration (IDD) patients. Materials and Methods: We retrieved microarray data set GSE70362, which contains the gene expression profiles of 24 AF and 24 NP samples from the Gene Expression Omnibus and identified DEGs in degenerative AF (AF-DEGs) and NP (NP-DEGs) samples compared with nondegenerative samples. We also examined gene expression profiles in WB from patients with IDD and healthy volunteers to identify DEGs in WB (WB-DEGs). We performed functional analyses on the DEGs common to AF-DEGs, NP-DEGs, and WB-DEGs. Expression of the common DEGs was partially validated by quantitative real-time-polymerase chain reaction (QRT-PCR). Results: In total, 846 AF-DEGs, 902 NP-DEGs, and 862 WB-DEGs were identified, and 22 DEGs were common among the three groups. Functional analyses showed that the common DEGs were enriched in 33 biological processes, 16 cellular components, 4 molecular functions, and 9 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways; 13 of the common DEGs were included in the protein-protein interaction (PPI) network and superoxide dismutase 2 (SOD2) was identified as a hub gene in the PPI network. The QRT-PCR results for the expression of the genes protein disulfide isomerase family A member 4, FKBP prolyl isomerase 11, ectonucleotide pyrophosphatase/phosphodiesterase 4, SOD2, and actin binding LIM protein 1, were consistent with the gene chip hybridization results. Conclusions: This study identified key genes for future investigations of the underlying molecular mechanisms of IDD. These genes may provide future targets for the clinical treatment and diagnosis of IDD.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31420796

RESUMO

Glutathione is a bioactive tripeptide composed of glycine, L-cysteine, and L-glutamate, and has been widely used in pharmaceutical, food, and healthy products. The current metabolic studies of glutathione were mainly focused on the native producing strains with precursor amino acid supplementation. In the present work, Corynebacterium glutamicum, a workhorse for industrial production of a series of amino acids, was engineered to produce glutathione. First, the introduction of glutathione synthetase gene gshF from Streptococcus agalactiae fulfilled the ability of glutathione production in C. glutamicum and revealed that L-cysteine was the limiting factor. Then, considering the inherent capability of L-glutamate synthesis and the availability of external addition of low-cost glycine, L-cysteine biosynthesis was enhanced using a varieties of pathway engineering methods, such as disrupting the degradation pathways of L-cysteine and L-serine, and removing the repressor responsible for sulfur metabolism. Finally, the simultaneously introduction of gshF and enhancement of cysteine formation enabled C. glutamicum strain to produce glutathione greatly. Without external addition of L-cysteine and L-glutamate, 756 mg/L glutathione was produced. This is first time to demonstrate the potential of the glutathione non-producing strain C. glutamicum for glutathione production and provide a novel strategy to construct glutathione-producing strains.

20.
Ann Surg ; 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31425290

RESUMO

OBJECTIVE: This large international cohort study aimed to investigate the associations of examined lymph node (ELN) number with accurate staging and long-term survival in pancreatic adenocarcinoma (PaC) and to robustly determine the minimal and optimal ELN thresholds. SUMMARY BACKGROUND DATA: ELN number is an important quality metric in cancer care. The recommended minimal ELN number in PaC to accurately stage cancer varies greatly across guidelines, and the optimal number especially to adequately stratify patient survival has not yet been established. METHODS: Population-based data on patients with stage I to II PaC resected in 2003 to 2015 from the US Surveillance, Epidemiology, and End Results (SEER)-18 Program and Netherlands National Cancer Registry (NCR) were analyzed. Associations of ELN number with stage migration and survival were evaluated using multivariable-adjusted logistic and Cox regression models, respectively. The series of odds ratios (ORs) for negative-to-positive node stage migration and hazard ratios (HRs) for survival with more ELNs were fitted using a LOWESS smoother, and structural breakpoints were determined by Chow test. RESULTS: Overall 16,241 patients were analyzed. With increasing ELN number, both cohorts exhibited significant proportional increases from node-negative to node-positive disease [ORSEER-18=1.05, 95% confidence interval (CI) = 1.04-1.05; ORNCR = 1.10, 95% CI = 1.08-1.12] and serial improvements in survival (HRSEER-18 = 0.98, 95% CI = 0.98-0.99; HRNCR = 0.98, 95% CI = 0.97-0.99) per additional ELN after controlling for confounders. Associations for stage migration and survival remained significant in most stratifications by patient, tumor, and treatment factors. Cut-point analyses suggested a minimal threshold ELN number of 11 and an optimal number of 19, which were validated both internally in the derivative US cohort and externally in the Dutch cohort with the ability to well discriminate different probabilities of both survival and stage migration. CONCLUSIONS: In stage I to II PaC, more ELNs are associated with more precise nodal staging, which might largely explain the survival association. Our observational study does not suggest causality, and does not encourage more extended lymphadenectomy before further randomized evidence is obtained. Our results robustly conclude 11 ELNs as the minimal and suggest 19 ELNs as the optimal cut-points, for evaluating quality of lymph node examination and possibly for stratifying postoperative prognosis.

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