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1.
Chemosphere ; 239: 124716, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31521938

RESUMO

During the past several years, abundant progresses has been made in the development of immobilized oxidative enzymes with focus on finding new support materials, improving the immobilization methods and their applications. Nowadays, immobilized oxidative enzymes are broadly accepted as a green way to face the challenge of high amounts of micropollutants in nature. Among all oxidative enzymes, laccases and horseradish peroxidase were used frequently in recent years as they are general oxidative enzymes with ability to oxidize various types of compounds. Immobilized laccase or horseradish peroxidase are showed better stability, and reusability as well as easy separation from reaction mixture that make them more favorable and economic in compared to free enzymes. However, additional improvements are still essential such as: development of the new materials for immobilization with higher capacity, easy preparation, and cheaper price. Moreover, immobilization methods are still need improving to become more efficient and avoid enzyme wasting during immobilization and enzyme leakage through working cycles.

2.
Int J Cancer ; 146(1): 103-114, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31199508

RESUMO

Next-generation sequencing of cell-free circulating DNA (cfDNA) has emerged as promising technique for identifying minimally invasive genomic profiling of tumor cells recently. However, it remains relatively unknown in LAM disease. In our study, paired cfDNA and genomic DNA (gDNA) in blood samples were obtained from 23 LAM patients and seven healthy controls to explore mutations profiles of targeted 70 cancer-related genes. As results, log2-based allele frequencies of mutations in cfDNA were significantly different from those of gDNA. By comparing the mutual mutations identified both in cfDNA and gDNA, a significant correlation was also observed. After removing mutations in gDNA, distinct somatic mutation profiles of cfDNA were observed in LAM patients. Forty of 70 targeted genes had recurrent mutations, of which ATM, BRCA2 and APC showed the highest frequency. Based on the mutation, correlation network constructed of 40 mutated genes, 11 hub genes bearing intensive interactions were highlighted, including BRCA1, BRCA2, RAD50, RB1, NF1, APC, MLH3, ATM, PDGFRA, PALB2 and BLM. Expression of the hub genes showed significant clusters between LAM patients and controls and that RAD50 and BRCA2 had the strongest associations with subject phenotypes. Myogenesis and estrogen response were confirmed to be positively regulated in LAM patients. Collectively, our study provided a landscape of genomic alterations in LAM and discovered several potential driver genes, that is, BRCA2 and RAD50, which shed a substantial light on the clinical application of key molecular markers and potential therapy targets for precision diagnosis and treatment in the future.

3.
Mol Imaging Biol ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792839

RESUMO

PURPOSE: Magnetic resonance imaging (MRI) has a high spatial resolution for detecting hepatocellular carcinoma (HCC). Integrin α6 has emerged as a diagnostic and prognostic biomarker of HCC. Here, we developed the MR contrast agent RWY-dL-(Gd-DOTA)4 based on the integrin α6-targeted RWY peptide that we previously identified to detect HCC. PROCEDURES: Contrast-enhanced MRI was carried out to evaluate the use of RWY-dL-(Gd-DOTA)4 to detect HCC lesions in subcutaneous and diethylnitrosamine (DEN)-induced HCC mouse models. RESULTS: Enhancement MR signals were observed in HCC-LM3 subcutaneous liver tumors in the first 5 min post-injection of RWY-dL-(Gd-DOTA)4 at a low dose of 0.03 mmol Gd/kg. Moreover, RWY-dL-(Gd-DOTA)4 generated superior contrast enhancement for liver tumors in chemical-induced HCC mice. Importantly, RWY-dL-(Gd-DOTA)4 provided complementary enhancement MR signals to the clinical available hepatobiliary MR contrast agent gadoxetate disodium Gd-EOB-DTPA. Additionally, RWY-dL-(Gd-DOTA)4 showed minimal gadolinium retention in normal tissues and organs at 48 h post-injection. CONCLUSION: These findings potentiate the use of RWY-dL-(Gd-DOTA)4 for the MRI of HCC to improve the diagnosis of HCC.

4.
Cancer Sci ; 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31785057

RESUMO

STMN1 has been regarded as an oncogene and its upregulation is closely associated with malignant behaviors and poor prognosis in multiple cancers. However, the detailed functions and underlying mechanisms of STMN1 are still largely unknown in hepatocellular carcinoma (HCC) development. Here, we analyzed STMN1 expression and the related clinical significance in HCC by using well-established Protein Atlas, TCGA and GEO cancer databases. The analysis indicated that STMN1 was highly expressed in HCC and closely associated with vascular invasion, higher histological grade, advanced clinical grade and shorter survival time in HCC patients. Overexpressing and silencing STMN1 in HCC cell lines demonstrated that STMN1 could regulate cell proliferation, migration, drug-resistance, cancer stem cell property in vitro as well as tumor growth in vivo. Further experiments demonstrated that STMN1 mediated intricate crosstalk between HCCs and hepatic stellate cells (HSCs) via triggering the HGF/MET signal pathway. When HSCs were cocultured with HCC cells, HSCs secreted more HGF to stimulate the expression of STMN1 in HCC cells. Mutually, STMN1 upregulation in HCC cells facilitated HSC activation to acquire CAF features. The MET inhibitor crizotinib significantly blocked this crosstalk and slowed tumor growth in vivo. In conclusion, our findings shed new insight on STMN1 functions, and suggest that STMN1 may hopefully be used as a potential marker to identify patients who benefit from MET inhibitor treatment.

5.
Sci Total Environ ; : 135687, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31785907

RESUMO

The impacts of ambient fine particulate matter (PM2.5) on public health are a worldwide concern. Epidemiological evidence has shown that PM2.5-triggered inflammatory cascades and lung tissue damage are important causes of chronic obstructive pulmonary disease (COPD). However, most laboratory studies of COPD have focused on animal models of cigarette smoke exposure or combined exposure to cigarette smoke and PM2.5. Furthermore, a single method is used to evaluate the development of COPD without integrality. In this study, we investigated pulmonary pathophysiological alterations using integrated functional, morphological, and biochemical techniques and a mouse model exposed to PM2.5 alone for 3 months. Emphysema in this model was confirmed by reconstructed three-dimensional micro-CT images. Typical histopathological signs were neutrophil/macrophage infiltration and accumulation at 2 months after exposure and emphysema/atelectasis at 3 months. Respiratory mechanical parameters confirmed that PM2.5 caused a decline in respiratory function. PM2.5 also triggered complex cytokine profile changes in the lungs with characteristic inflammation-related tissue destruction. This study showed that chronic PM2.5 exposure impaired lung function, triggered emphysematous lesions, and induced pulmonary inflammation and airway wall remodeling. Most importantly, prolonged exposure to PM2.5 alone caused COPD in mice. These results improve the understanding of the mechanisms and mediators underlying PM2.5-induced COPD.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31787230

RESUMO

Sleep deprivation (SD) has detrimental effects on the physiological function of the brain. However, the underlying mechanism remains elusive. In the present study, we investigated the expression of candidate plasticity-related gene 15 (cpg15), a neurotrophic gene, and its potential role in SD using a REM-SD mouse model. Immunofluorescent and Western blot analysis revealed that the expression of cpg15 protein decreased in the hippocampus, ventral group of the dorsal thalamus (VENT), and somatosensory area of cerebral cortex (SSP) after 24-72 h of REM-SD, and the oxidative stress in these brain regions was increased in parallel, as indicated by the ratio of glutathione (GSH) to its oxidative product (GSSG). Over-expression of cpg15 in thalamus, hippocampus, and cerebral cortex mediated by AAV reduced the oxidative stress in these regions, indicating that the decrease of cpg15 might be a cause that augments oxidative stress in the sleep deprived mouse brain. Collectively, the results imply that cpg15 may play a protective function in the SD-subjected mouse brain via an anti-oxidative function. To our knowledge, this is the first time to provide evidences in the role of cpg15 against SD-induced oxidative stress in the brain.

7.
Int J Hyperthermia ; 36(sup1): 74-82, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31795830

RESUMO

Purpose: To characterize the T cell receptor (TCR) repertoire, serum cytokine levels, peripheral blood T lymphocyte populations, safety, and clinical efficacy of hyperthermia (HT) combined with autologous adoptive cell therapy (ACT) and either salvage chemotherapy (CT) or anti-PD-1 antibody in patients with previously treated advanced solid tumors.Materials and methods: Thirty-three (33) patients with ovarian, pancreatic, gastric, colorectal, cervical, or endometrial cancer were recruited into the following therapeutic groups: HT + ACT (n = 10), HT + ACT + anti-PD-1 inhibitor (pembrolizumab) (n = 11) and HT + ACT + CT (n = 12). Peripheral blood was collected to analyze TCR repertoire, measurements of cytokines levels and lymphocyte sub-populations before and after treatment.Results: The objective response rate (ORR) was 30% (10/33), including three complete responses (CR) (9.1%) and seven partial responses (PR) (21.2%) and a disease control rate (DCR = CR + PR + SD) of 66.7% (22 of 33). The most common adverse reactions, blistering, subcutaneous fat induration, local heat-related pain, vomiting and sinus tachycardia, were observed in association with HT. IL-2, IL-4, TNF-α, and IFN-γ levels in peripheral blood were significantly increased among the clinical responders (p < 0.05) while IL-6 and IL-10 were elevated among those with progressive disease (p < 0.05). Peripheral blood CD8+/CD28+ T cells increased (p = 0.002), while the CD4+/CD25+/CD127+Treg cells decreased after therapy (p = 0.012). TCR diversity was substantially increased among the clinical responders.Conclusions: Combining HT with ACT plus either CT or anti-PD-1 antibody was safe, generated clinical responses in previously treated advanced cancers, and promoted TCR repertoire diversity and favorable changes in serum IL-2, IL-4, TNF-α, and IFN-γ levels in clinical responders.

8.
Technol Cancer Res Treat ; 18: 1533033819892590, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31795847

RESUMO

OBJECTIVE: The aim of this study was to investigate the microRNA-200b-3p expression in lung adenocarcinoma and the possible functional associations of microRNA-200b-3p with cell proliferation, migration, and invasion. METHODS: Quantitative real-time polymerase chain reaction was used to detect the expression of microRNA-200b-3p in lung adenocarcinoma samples and in the human lung adenocarcinoma cell lines A549 and H1299. A549 and H1299 cells were transfected with either a microRNA-200b-3p mimic or a negative control microRNA or either an empty vector or an adenosine triphosphate-binding cassette transporter A-1 overexpression vector. A Cell Counting Kit-8 assay was employed to assess the ability of cell proliferation. Transwell assays and transwell-Matrigel invasion assay were, respectively, utilized to assess the capacity of migration and invasion in A549 and H1299 cells. RESULTS: The results showed that microRNA-200b-3p expression was significantly upregulated in tumor tissues compared with that in adjacent normal tissues. Overexpression of microRNA-200b-3p promoted lung adenocarcinoma cell proliferation and metastasis. Furthermore, adenosine triphosphate-binding cassette transporter A-1 was a direct target of microRNA-200b-3p, and this binding was verified by luciferase reporter analysis. Overexpression of adenosine triphosphate-binding cassette transporter A-1 obviously suppressed lung adenocarcinoma cell proliferation, migration, and invasion. Lung adenocarcinoma cell phenotypes induced by microRNA-200b-3p overexpression could be partially remitted by the co-overexpression of microRNA-200b-3p and adenosine triphosphate-binding cassette transporter A-1. CONCLUSION: This study first identified that microRNA-200b-3p is upregulated in lung adenocarcinoma cells and associated with cell proliferation and metastasis. MicroRNA-200b-3p promoted lung adenocarcinoma cell proliferation and metastasis by suppressing adenosine triphosphate-binding cassette transporter A-1. MicroRNA-200b-3p may function as a novel molecular marker and therapeutic target for lung adenocarcinoma treatment.

9.
Environ Pollut ; : 113627, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31796321

RESUMO

Lead (Pb) is one of the predominant heavy metals in e-waste recycling arears and recognized as a notorious environmental neurotoxic substance. However, whether Pb at environmentally relevant concentrations could cause neurobehavioral alteration and even what kind of signaling pathway Pb exposure would disrupt in zebrafish were not fully uncovered. In the present study, 6 h postfertilization (hpf) zebrafish embryos were exposed to Pb at the concentrations of 0, 5, 10, and 20 µg/L until 144 hpf. Then the neurobehavioral indicators including locomotor, turnings and social behaviors, and the expressions of selected genes concerning brain-derived neurotrophic factor (BDNF) signaling were investigated. The results showed that significant changes were obtained under 20 µg/L Pb exposure. The hypoactivity of zebrafish larvae in locomotor and turning behaviors was induced during the dark period, while hyperactivity was observed in a two-fish social assay during the light period. The significantly downregulation of genes encoding BDNF, its receptor TrkB, and N-methyl-D-aspartate glutamate receptor (NMDAR) suggested the involvement of NMDAR-dependent BDNF signaling pathway. Overall, our study demonstrated that developmental exposure to Pb at environmentally relevant concentrations caused obvious neurobehavioral impairment of zebrafish larvae by disrupting the NMDAR-dependent BDNF signaling, which could exert profound ecological consequences in the real environment.

10.
J Transl Med ; 17(1): 403, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31801571

RESUMO

BACKGROUND: Although there is abundant evidence indicating the connection between triglyceride and type 2 diabetes mellitus (T2DM), few reports or cohort studies confirm that high TG concentration may predict the incidence of T2DM independently. Thus, we studied the association between triglyceride (TG) and T2DM in a male-dominated, middle and older aged cohort, Tianjin General Hospital Cohort. And we further verified our results in the China Health and Retirement Longitudinal Study (CHARLS). METHODS: We conducted an 8-year retrospective cohort study (2009-2017) with 7241 participants who were free from T2DM at baseline. Three groups were constructed based on baseline TG levels (normal, borderline-high, and high). We used a Cox proportional hazards model to evaluate the relationship between TG and T2DM after adjusting for possible risk factors. A Kaplan-Meier survival analysis was performed to compare the incidence of T2DM among subjects in each TG group. We also tested the association between TG and T2DM in the CHARLS cohort. RESULTS: In Tianjin General Hospital Cohort, 7241 participants (male 75.8%, female 24.2%) were included, mean age was 61.49 ± 13.85 years at baseline. The cumulative incidence of T2DM in our cohort study was 8.6% (9.2% in men and 6.6% in women). Compared with the normal TG group, the hazard ratios in the borderline and high group were 1.30 (95% CI 1.04-1.62) and 1.54 (95% CI 1.24-1.90). The Kaplan-Meier survival analysis indicated that higher TG levels may predict higher onset of T2DM. These results were verified in the CHARLS cohort, the hazard ratio with T2DM (95% CI) for logTG was 3.94 (2.64-5.87). CONCLUSIONS: Our findings suggest that the TG level may be an independent risk factor and predictor for T2DM.

12.
Theranostics ; 9(24): 7403-7416, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695776

RESUMO

Bone marrow mesenchymal stem cell (MSC)-derived small extracellular vesicles (sEVs) have been widely used for treating myocardial infarction (MI). However, low retention and short-lived therapeutic effects are still significant challenges. This study aimed to determine whether incorporation of MSC-derived sEVs in alginate hydrogel increases their retention in the heart thereby improving therapeutic effects. Methods: The optimal sodium alginate hydrogel incorporating sEVs system was determined by its release ability of sEVs and rheology of hydrogel. Ex vivo fluorescence imaging was utilized to evaluate the retention of sEVs in the heart. Immunoregulation and effects of sEVs on angiogenesis were analyzed by immunofluorescence staining. Echocardiography and Masson's trichrome staining were used to estimate cardiac function and infarct size. Results: The delivery of sEVs incorporated in alginate hydrogel (sEVs-Gel) enhanced their retention in the heart. Compared with sEVs only treatment (sEVs), sEVs-Gel treatment significantly decreased cardiac cell apoptosis and promoted the polarization of macrophages at day 3 after MI. sEVs-Gel treatment also increased scar thickness and angiogenesis at four weeks post-infarction. Measurement of cardiac function and infarct size were significantly better in the sEVs-Gel group than in the group treated with sEVs only. Conclusion: Delivery of sEVs incorporated in alginate hydrogel provides a novel approach of cell-free therapy and optimizes the therapeutic effect of sEVs for MI.

13.
Math Biosci Eng ; 16(6): 7911-7920, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31698646

RESUMO

For the accuracy of Specific Absorption Rate (SAR) measurement, there is a need to have the measuring instrument, the E-field probe, calibrated on a regular basis, however, the conventional calibration approach can be complicated for an encapsulated dosimestic E-field probe. This paper proposed a new method to obtain the conversion factor of the E-field probe in the simulant tissue. The novelty of this proposal is that it can simplify the procedure of the conversion factor analysis, by employing the liquid waveguide with known E-filed as a component of the reference field to compare with the measured E-field of the dosimestic probe immersed in the equivalent-tissue liquid. Also, this paper evaluated the uncertainty of calibration for this method.

14.
Clin Ther ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31699438

RESUMO

PURPOSE: Mantle cell lymphoma (MCL) is a rare subtype of B-cell non-Hodgkin lymphoma that can be either aggressive or indolent. Although MCL usually responds well to initial treatment with chemotherapy-based regimens, the disease often relapses or becomes refractory within a few years. Acalabrutinib is a highly selective, potent, covalent Bruton tyrosine kinase inhibitor with minimal off-target activity. WIthout head-to-head clinical trial data, estimation of the comparative efficacy and safety of new therapeutic entities provides valuable information for patients, clinicians, and health care payers. The objective of this analysis was to compare the efficacy and safety of acalabrutinib versus other targeted therapies employed for the treatment of relapsed/refractory MCL by using matching-adjusted indirect comparisons. METHODS: Individual data from 124 patients treated with acalabrutinib in the Phase II ACE-LY-004 trial were adjusted to match average baseline characteristics of populations from studies using alternative targeted treatment regimens for relapsed/refractory MCL (for monotherapy: ibrutinib, bortezomib, lenalidomide, and temsirolimus; for combination therapies: ibrutinib + rituximab, bendamustine + rituximab, and lenalidomide + rituximab). Patient populations were matched on age, sex, race, Eastern Cooperative Oncology Group performance status, Simplified MCL International Prognostic Index score, tumor bulk, lactate dehydrogenase concentration, extranodal disease, bone marrow involvement, and number of previous treatment regimens. Outcomes assessed included overall response rate (ORR), complete response (CR) rate, overall survival (OS), progression-free survival (PFS), and adverse events. FINDINGS: After matching, acalabrutinib was associated with significant increases in ORR and CR rate (estimated treatment difference [95% CI]) versus ibrutinib (ORR, 9.3% [0.3-18.3]; CR, 14.9% [5.4-24.3]), bortezomib (ORR, 50.6% [40.2-61.0]; CR, 18.8% [9.1-28.5]), lenalidomide (ORR, 38.1% [27.1-49.1]; CR, 43.5% [34.8-52.3]), and temsirolimus (ORR, 40.7% [31.0-50.4]; CR, 27.1% [19.2-35.0]). PFS (hazard ratio [95% CI]) with acalabrutinib was significantly increased versus bortezomib (0.36 [0.26-0.51]), lenalidomide (0.65 [0.48-0.89]), lenalidomide + rituximab (0.57 [0.35-0.93]), and temsirolimus (0.33 [0.24-0.45]). Acalabrutinib was associated with significantly increased OS (hazard ratio) versus bortezomib (0.36 [0.22-0.61]) and temsirolimus (0.32 [0.23-0.44]). The overall safety profile of acalabrutinib was similar or better compared with the monotherapies; however, infection risk increased versus bendamustine + rituximab, and anemia increased risk versus lenalidomide + rituximab and ibrutinib + rituximab. IMPLICATIONS: This comparison of targeted therapies used in the treatment of relapsed/refractory MCL showed that acalabrutinib has the potential to provide increased response rates, with trends for increased PFS and OS, and an improved safety profile.

15.
Sci Total Environ ; 688: 1205-1215, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31726551

RESUMO

As antibiotics are widely consumed, fluoroquinolones (FQs) behave to have huge hidden danger to human health. Various agricultural residues have potential to produce biochar rich in porous structure for adsorption of contaminants. In this study, potato leaves and stems were pyrolyzed at 500 °C under anoxic condition for biochar (BC) preparation. At the same conditions, magnetic biochar (MBC) and humic acid (HA) coated magnetic biochar (HAB) were also prepared. In particular, characterizations of HAB showed the extensive coating of HA on MBC surface and introducing more oxygen-containing groups, which may promote the adsorption capacity of biochar. Three typical FQs (ciprofloxacin (CIP), norfloxacin (NOR) and enrofloxacin (ENR)) were used as target contaminants to further investigate the adsorption property of HAB. Compared with BC and MBC, novel adsorbent HAB due to introduction of HA exhibited better FQs adsorption ability, and its maximum adsorption capacity for CIP, NOR and ENR were 1.80, 1.67 and 1.70 times higher than those of MBC and were 3.40, 2.88, 2.96 times higher than those of raw BC, respectively. Pseudo-second-order kinetic model and Langmuir isotherm model could describe the process of FQs adsorbed on HAB more appropriately, and thermodynamic results illustrated that the sorption process was spontaneous and endothermic. In addition, FQs adsorption by HAB was increased with initial solution pH from 3.0 to 10.0, while it was slightly decreased with ionic strength rising (0.001-0.1 M CaCl2). Combined with FTIR results, high FQs removal efficiency could be attributed to electrostatic, hydrophobic, H-bond and π-π EDA interactions.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31692167

RESUMO

Prion-like trans-cellular spreading of tau in Alzheimer's Disease (AD) is mediated by tau binding to cell surface heparan sulfate (HS). However, the structural determinants for tau-HS interaction are not well understood. Microarray and SPR assays of structurally-defined HS oligosaccharides show that a rare 3-O-sulfation(3-O-S) of HS significantly enhances tau binding. In Hs3st1-/- (HS 3-O-sulfotransferase-1 knockout) cells, reduced 3-O-S levels of HS diminished both cell surface binding and internalization of tau. In cell culture, the addition of 3-O-S HS 12-mer reduced both tau cell surface binding and cellular uptake. NMR titration mapped 3-O-S binding sites to microtubule binding repeat 2 (R2) and proline-rich region 2 (PRR2) of tau. Tau is only the 7th protein currently known to recognize HS 3-O-sulfation. Our work demonstrates that this rare 3-O-sulfation enhances tau-HS binding and likely the trans-cellular spread of tau, providing a novel target for disease modifying treatment of AD and other tauopathy.

17.
J Am Chem Soc ; 141(46): 18380-18384, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31682419

RESUMO

Hedgehog (Hh) autoprocessing converts Hh precursor protein to cholesterylated Hh ligand for downstream signaling. A conserved active-site aspartate residue, D46, plays a key catalytic role in Hh autoprocessing by serving as a general base to activate substrate cholesterol. Here we report that a charge-altering Asp-to-His mutant (D46H) expands native cholesterylation activity and retains active-site conformation. Native activity toward cholesterol was established for D46H in vitro using a continuous FRET-based autoprocessing assay and in cellulo with stable expression in human 293T cells. The catalytic efficiency of cholesterylation with D46H is similar to that with wild type (WT), with kmax/KM = 2.1 × 103 and 3.7 × 103 M-1 s-1, respectively, and an identical pKa = 5.8 is obtained for both residues by NMR. To our knowledge this is the first example where a general base substitution of an Asp for His preserves both the structure and activity as a general base. Surprisingly, D46H exhibits increased catalytic efficiency toward non-native substrates, especially coprostanol (>200-fold) and epicoprostanol (>300-fold). Expanded substrate tolerance is likely due to stabilization by H46 of the negatively charged tetrahedral intermediate using electrostatic interactions, which are less constrained by geometry than H-bond stabilization by D46. In addition to providing fundamental insights into Hh autoprocessing, our findings have important implications for protein engineering and enzyme design.

18.
Artigo em Inglês | MEDLINE | ID: mdl-31743562

RESUMO

Polyphosphate (PolyP) is one of the most compacted inorganic polyanionic biopolymers that participate in various indispensable physiological processes. However, the mechanism of the interaction between polyP and proteins remain poorly understood. Here, we report that polyP can interact with positively charged green fluorescent protein, +36GFP, to perform liquid-liquid phase separation (LLPS) within minutes by intermolecular electrostatic interactions in vivo. Upon nutrient downshift induction, genetically engineered Citrobacter freundii accumulates intracellular polyP at a rate of 210 µM/min, which is consistent with Kornberg's observation and results in the thorough compartmentalization of polyP/+36GFP complexes in a polar-localization fashion within 1 h. In vitro studies showed that medium chain-length polyP (60-mer) was competent enough to provoke the phase separation of +36GFP at a concentration as low as 200 nmol, a value of the same magnitude as native proteins. In contrast, short chain-length polyP (14-mer) had no detectable capacity under the same circumstances. These results suggest a general approach to manipulate protein-protein interactions through LLPS using an inorganic biopolymer.

19.
Cancer Sci ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746531

RESUMO

The effect of hepatitis C virus p7 trans-regulated protein 3 (P7TP3) in the development of hepatocellular carcinoma (HCC) is still unknown. This study aimed to investigate the role and mechanism of P7TP3 in HCC. P7TP3 was significantly decreased in HCC tissues when compared with corresponding liver tissues just around the tumor (LAT) from 7 HCC patients. Fewer and smaller colonies were originated from HepG2-P7TP3 cells when compared to HepG2-NC cells. Overexpression of P7TP3 in HepG2 cells has significantly repressed the growth of HCC xenografts in nude mice. Furthermore, wound-healing tests, transwell assays, matrigel transwell assays, adhesion assays, CCK-8 assays, flow cytometry and western blotting analysis revealed that P7TP3 protein expression inhibited migration, invasion, adhesion, proliferation and cell cycle progression in HCC cell lines. Moreover, P7TP3 suppressed the activity of Wnt/ß-catenin signaling pathway, and was restored by Wnt3a, which is an activator of Wnt/ß-catenin signaling pathway. Consistently, ß-catenin was highly expressed by P7TP3 silencing, and restored by XAV939, an inhibitor of Wnt/ß-catenin signaling pathway. Finally, miR-182-5p suppressed the expression of target gene P7TP3 by directly interacting with 3'-UTR region. Taken together, P7TP3, the direct target gene of miR-182-5p, inhibited HCC by regulating migration, invasion, adhesion, proliferation and cell cycle progression of liver cancer cell via Wnt/ß-catenin signaling pathway. These findings provide strong evidence that P7TP3 acts as a new promising tumor suppressor in HCC.

20.
Brain Behav Immun ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31707083

RESUMO

BACKGROUND: Neuroinflammation is a characteristic pathological change of acute neurological deficit and chronic traumatic encephalopathy (CTE) after traumatic brain injury (TBI). Microglia are the key cell involved in neuroinflammation and neuronal injury. The type of microglia polarization determines the direction of neuroinflammation. MiR-21-5p elevated in neurons and microglia after TBI in our previous research. In this study, we explore the influence of miR-21-5p for neuroinflammation by regulating microglia polarization. METHODS: In this study, PC12 and BV2 used to instead of neuron and microglia respectively. The co-cultured transwell system used to simulate interaction of PC12 and BV2 cells in vivo environment. RESULTS: We found that PC12-derived exosomes with containing miR-21-5p were phagocytosed by microglia and induced microglia polarization, meanwhile, the expression of miR-21-5p was increased in M1 microglia cells. Polarization of M1 microglia aggravated the release of neuroinflammation factors, inhibited the neurite outgrowth, increased accumulation of P-tau and promoted the apoptosis of PC12 cells, which formed a model of cyclic cumulative damage. Simultaneously, we also got similar results in vivo experiments. CONCLUSIONS: PC12-derived exosomes with containing miR-21-5p is the essential of this cyclic cumulative damage model. Therefore, regulating the expression of miR-21-5p or the secretion of exosomes may be an important novel strategy for the treatment of neuroinflammation after TBI.

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