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2.
Food Chem ; 306: 125626, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31627083

RESUMO

The effect of glycine betaine (GB) on chilling injury (CI)-induced pericarp browning in 'Nanguo' pears was investigated during shelf life at 20 °C after storage at 0 °C for 120 d. GB treatment alleviated the severity of browning in 'Nanguo' pears as represented by lower browning index (BI) and browning incidence. Membrane lipid peroxidation in GB-treated fruit was lower than that in the control, and membrane integrity was maintained in good condition. The activities and expression of ascorbate peroxidase (APX), catalase (CAT), and superoxide dismutase (SOD) were higher in GB-treated fruit than in control fruit. Furthermore, significantly higher proline content, proline synthesis key enzyme activities, and gene expression were observed in the treated fruit, including ornithine d-aminotransferase (OAT) and Δ1-pyrroline-5-carbox-ylate synthetase (P5CS), which were consistent with the browning tendency. In a nutshell, GB treatment can effectively alleviate pericarp browning of cold-stored 'Nanguo' pears by regulating antioxidant enzymes and proline metabolism.

3.
Biosens Bioelectron ; 148: 111819, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31678825

RESUMO

In this paper, a sensor based on a magnetic surface molecularly imprinted membrane (MMIP) was prepared for the highly sensitive and selective determination of acetaminophen (AP). Before the experiment, the appropriate functional monomers and solvents required for the polymer were screened, and the molecular electrostatic potentials (MEPs) were calculated by the DFT/B3LYP/6-31 + G method. MMIP with high recognition of AP was synthesized based on Fe3O4@SiO2nanoparticles (NPs) with excellent core-shell structure. Next, a carbon paste electrode (CPE) was filled with a piece of neodymium-iron-boron magnet to make magnetic electrode (MCPE), and MMIP/MCPE sensor was obtained by attaching a printed polymer to the surface of the electrode under the strong magnetic. Due to the stable molecular structure of the electrode surface, the sensor is highly effective and accurate for detection of AP using DPV. The DPV response of the sensor exhibited a linear dependence on the concentration of AP from 6 × 10-8 to 5 × 10-5 mol L-1 and 5 × 10-5 to 2 × 10-4 mol L-1, with a detection limit based on the lower linear range of 1.73 × 10-8 mol L-1(S/N = 3). When used for determination of AP in actual samples, the recovery of the sensor to the sample was 95.80-103.76%, and the RSD was 0.78%-3.05%.

4.
Chemosphere ; 238: 124649, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31466005

RESUMO

Electro-Fenton (EF) with peroxi-coagulation (PC) as an emerging electro-chemical advanced oxidation method has been extensively applied to treat refractory wastewater. However, the studies on the pretreatment of the raw coke plant wastewater by EF process were still lacking. In this study, a lab-scale EF system (Fe as anode and graphite as cathode) achieved the highest COD removal of 69.2% based on the preliminary experiments. The process parameters and corresponding COD removal performance were further optimized using response surface methodology (RSM) combined with Box-Behnken experimental design (BBD). The optimal conditions were obtained as: 3.2 mA cm-2 of current density, 2 h of the reaction time and 2.6 of the initial pH value, with the COD removal reaching 70.0%. Fourier infrared (FTIR), fluorescence excitation-emmission matrix (EEM) and gas chromatography-mass spectrometry (GC-MS) also revealed the degradation behaviors of dissolved organic matters (DOMs) by characterizing their structures and compositions before and after EF pretreatment, thus greatly improving the biodegradability of the wastewater. Moreover, the EF process for COD removal well followed third-order kinetics model. These findings give helpful guidance to design, optimize and control the EF process as a favourable pretreatment for actual refractory coking wastewater in practice.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31784085

RESUMO

Acute pancreatitis (AP) is one of the leading causes of hospital admission for gastrointestinal disorders. Although lipid peroxides are produced in AP, it is unknown if targeting lipid peroxides prevents AP. This study aimed to investigate the role of mitochondrial aldehyde dehydrogenase 2 (ALDH2), a critical enzyme for lipid peroxide degradation, in AP and the possible underlying mechanisms. Cerulein was used to induce AP in C57BL/6 J male mice and pancreatic acinar cells were used to elucidate underlying mechanisms in vitro. Pancreatic enzymes in the serum, lipid peroxidation products malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), and Bcl-2, Bax and cleaved caspase-3 were measured. ALDH2 activation with a small-molecule activator, Alda-1, reduced the levels of the pancreatic enzymes in the serum and the lipid peroxidation products MDA and 4-HNE. In addition, Alda-1 decreased Bax and cleaved caspase-3 expression and increased Bcl-2 expression in vivo and in vitro. In conclusion, ALDH2 activation by Alda-1 has a protective effect in cerulein-induced AP by mitigating apoptosis in pancreatic acinar cells by alleviating lipid peroxidation.

6.
Nat Commun ; 10(1): 5458, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784534

RESUMO

The studies of quantum interference effects through bulk perovskite materials at the Ångstrom scale still remain as a major challenge. Herein, we provide the observation of room-temperature quantum interference effects in metal halide perovskite quantum dots (QDs) using the mechanically controllable break junction technique. Single-QD conductance measurements reveal that there are multiple conductance peaks for the CH3NH3PbBr3 and CH3NH3PbBr2.15Cl0.85 QDs, whose displacement distributions match the lattice constant of QDs, suggesting that the gold electrodes slide through different lattice sites of the QD via Au-halogen coupling. We also observe a distinct conductance 'jump' at the end of the sliding process, which is further evidence that quantum interference effects dominate charge transport in these single-QD junctions. This conductance 'jump' is also confirmed by our theoretical calculations utilizing density functional theory combined with quantum transport theory. Our measurements and theory create a pathway to exploit quantum interference effects in quantum-controlled perovskite materials.

7.
Drug Des Devel Ther ; 13: 3693-3704, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695336

RESUMO

Purpose: Spinal cord injury (SCI) is a relatively common, devastating traumatic condition resulting in permanent disability. In this study, the use of exosomes derived from bone mesenchymal stem cells (BMSCs-Exo) as a cell-free therapy for the treatment of SCI in rats was investigated to gain insights into their mechanisms of action. Methods: Rats were randomly divided into three groups, Sham (treated with PBS), SCI (SCI injury + PBS) and SCI + Exo (SCI injury + BMSCs-Exo). Changes in the complement system between the three groups were assessed with the use of proteomics. The proteomic data were verified using reverse transcription-polymerase chain reaction (RT-PCR). In addition, the distributions of BMSCs-Exo in rats with SCI were detected by immunofluorescence. Moreover, SCI-activated NF-κB levels were determined using Western blot. Results: SCI insult increased complement levels, including C4, C5, C6, C4 binding protein alpha and complement factor H. In contrast, the SCI + BMSCs-Exo group exhibited attenuated SCI-induced complement levels. Immunofluorescence assay results revealed that BMSCs-Exo mainly accumulated at the spinal cord injury site and were bound to microglia cells. Western blot analysis of tissue lysates showed that BMSCs-Exo treatment also inhibited SCI-activated nuclear factor kappa-B (NF-κB). Conclusion: BMSCs-Exo play a protective role in spinal cord injury by inhibiting complement mRNA synthesis and release and by inhibiting SCI-activated NF-κB by binding to microglia.

8.
Blood ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31697823

RESUMO

To study the mechanisms of relapse in acute lymphoblastic leukemia (ALL), we performed whole-genome sequencing of 103 diagnosis-relapse-germline trios and ultra-deep sequencing of 208 serial samples in 16 patients. Relapse-specific somatic alterations were enriched in 12 genes (NR3C1, NR3C2, TP53, NT5C2, FPGS, CREBBP, MSH2, MSH6, PMS2, WHSC1, PRPS1, and PRPS2) involved in drug response. Their prevalence was 17% in very early relapse (<9 months from diagnosis), 65% in early relapse (9-36 months), and 32% in late relapse (>36 months) groups. Convergent evolution, where multiple subclones harbor mutations in the same drug resistance gene, was observed in six relapses and confirmed by single-cell sequencing in one case. Mathematical modeling and mutational signature analysis indicated that early relapse resistance acquisition was frequently two-step process where a persistent clone survived initial therapy, and later acquired bona fide resistance mutations during therapy. In contrast, very early relapses arose from pre-existing resistant clone(s). Two novel relapse-specific mutational signatures, one of which was caused by thiopurine treatment based on in vitro drug exposure experiments, were identified in early and late relapses but were absent from 2,540 pan-cancer diagnosis samples and 129 non-ALL relapses. The novel signatures were detected in 27% of relapsed ALLs and were responsible for 46% of acquired resistance mutations in NT5C2, PRPS1, NR3C1, and TP53. These results suggest that chemotherapy-induced drug resistance mutations facilitate a subset of pediatric ALL relapses.

9.
Biosci Trends ; 13(5): 423-429, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31666440

RESUMO

In-stent restenosis is highly related to the deposition of inflammatory extracellular matrix and the migration of endothelial and vascular smooth muscle cells. The miR-17/TIMP-1/interleukin pathway regulates vascular matrix remodeling and plays an important role in the inflammatory reaction. This study identified miR-17 and its related biomarkers in serum that potentially indicated susceptibility to in-stent restenosis (ISR) after coronary artery stenting. Subjects were 42 patients with single de novo coronary artery lesions who underwent regular coronary angiography one year after percutaneous coronary intervention. The clinical baseline information was recorded. Serum levels of biomarkers (including miR-17, TIMP-1, IL-6, IL-8, IL-2R, TNF-alpha, IL-10, and IL-1beta) were measured with real-time PCR or ELISA. Intergroup comparisons were used to compare patients with or without ISR. Compared to levels in the non-restenosis group, the serum miR-17 level was significantly higher (3.13 ± 0.22 vs. 1.06 ± 0.04, p < 0.01) and the serum TIMP-1 and IL-6 levels were significantly lower in the ISR group (TIMP-1: 0.33 ± 0.04 vs. 1.00 ± 0.05, p < 0.01; IL-6: 1.64 ± 0.18 vs. 3.52 ± 0.11, p < 0.01). Moreover, the levels of TIMP-1 and IL-6 decreased as the level of miR-17 increased. Spearman's correlation analysis indicated that the miR-17 level was inversely correlated with TIMP-1 and IL-6 levels. Findings suggest that an elevated level of miR-17 and decreased levels of TIMP-1 and IL-6 may be associated with the risk of ISR, which is in accordance with vascular matrix remodeling and an inflammatory reaction during the pathologic process of ISR. This study highlighted the potential for miR-17, TIMP-1, and IL-6 to serve as biomarkers for ISR.

10.
Gut ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31744909

RESUMO

OBJECTIVE: Familial adenomatous polyposis (FAP) is characterised by the development of hundreds to thousands of adenomas at different evolutionary stages in the colon and rectum that will inevitably progress to adenocarcinomas if left untreated. Here, we investigated the genetic alterations and transcriptomic transitions from precancerous adenoma to carcinoma. DESIGN: Whole-exome sequencing, whole-genome sequencing and single-cell RNA sequencing were performed on matched adjacent normal tissues, multiregionally sampled adenomas at different stages and carcinomas from six patients with FAP and one patient with MUTYH-associated polyposis (n=56 exomes, n=56 genomes and n=8,757 single cells). Genomic alterations (including copy number alterations and somatic mutations), clonal architectures and transcriptome dynamics during adenocarcinoma carcinogenesis were comprehensively investigated. RESULTS: Genomic evolutionary analysis showed that adjacent lesions from the same patient with FAP can originate from the same cancer-primed cell. In addition, the tricarboxylic acid cycle pathway was strongly repressed in adenomas and was then slightly alleviated in carcinomas. Cells from the 'normal' colon epithelium of patients with FAP already showed metabolic reprogramming compared with cells from the normal colon epithelium of patients with sporadic colorectal cancer. CONCLUSIONS: The process described in the previously reported field cancerisation model also occurs in patients with FAP and can contribute to the formation of adjacent lesions in patients with FAP. Reprogramming of carbohydrate metabolism has already occurred at the precancerous adenoma stage. Our study provides an accurate picture of the genomic and transcriptomic landscapes during the initiation and progression of carcinogenesis, especially during the transition from adenoma to carcinoma.

11.
J Card Surg ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730718

RESUMO

A 74-year-old woman with left main and three-vessel coronary artery disease was scheduled for off-pump coronary artery bypass grafting and developed acute severe cholecystitis preoperatively. Percutaneous gallbladder drainage was placed to achieve gallbladder decompression and infection control. Two weeks later, CABG and laparoscopic cholecystectomy were successfully performed at the same time.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31671052

RESUMO

A Gram-stain-negative, strictly aerobic, non-motile and non-pigmented spirillum, designated strain LZ-5T, was isolated from cultures of the paralytic shellfish poisoning (PSP) toxin-producing marine dinoflagellate Alexandrium catenella LZT09 collected from the Zhoushan sea area in the East China Sea during an algal bloom. The isolate grew at 4-40 °C (optimum, 25-33 °C) and pH 5.0-9.0 (optimum, 7.5) in the presence of 0.5-10 % (w/v) NaCl (optimum, 4.0 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain LZ-5T clearly belonged to the genus Saccharospirillum of the family Saccharospirillaceae. Strain LZ-5T shared highest 16S rRNA gene sequence similarity with Saccharospirillum impatiens EL-105T (98.9 %), Saccharospirillum mangrovi HK-33T (97.2 %), Saccharospirillum correiae CPA1T (96.8 %), Saccharospirillum salsuginis YIM-Y25T (96.8 %) and Saccharospirillum aestuarii IMCC 4453T (95.1 %). The average nucleotide identity and in silico DNA-DNA hybridization between strain LZ-5T and the two most closely related Saccharospirillum strains, S. impatiens EL-105T and S. mangrovi HK-33T, were 82.2 and 19.3 %, and 72.2 and 13.2 %, respectively. The predominant respiratory quinone of strain LZ-5T was Q-8, and the major fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0. The polar lipids of strain LZ-5T were diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), phosphatidylcholine (PC), glycolipid (GL), two unidentified glycophospholipids (GPLs), three unidentified aminophospholipids (APLs) and two unidentified lipids. The genomic DNA G+C content was 57.2 mol%. On the basis of this polyphasic characterization, strain LZ-5T represents a novel species of the genus Saccharospirillum, for which the name Saccharospirillum alexandrii sp. nov. is proposed. The type strain is LZ-5T (=KCTC 62460T=CCTCC AB2017232T).

13.
Clin Pharmacol Ther ; 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31709525

RESUMO

This white paper presents principles for validating proarrhythmia risk prediction models for regulatory use as discussed at the In Silico Breakout Session of a Cardiac Safety Research Consortium/Health and Environmental Sciences Institute/US Food and Drug Administration-sponsored Think Tank Meeting on May 22, 2018. The meeting was convened to evaluate the progress in the development of a new cardiac safety paradigm, the Comprehensive in Vitro Proarrhythmia Assay (CiPA). The opinions regarding these principles reflect the collective views of those who participated in the discussion of this topic both at and after the breakout session. Although primarily discussed in the context of in silico models, these principles describe the interface between experimental input and model-based interpretation and are intended to be general enough to be applied to other types of nonclinical models for proarrhythmia assessment. This document was developed with the intention of providing a foundation for more consistency and harmonization in developing and validating different models for proarrhythmia risk prediction using the example of the CiPA paradigm.

14.
Food Chem ; : 125737, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31780227

RESUMO

Chlorophyll degradation is the main reason for postharvest yellowing of broccoli. To uncover the role of jasmonic acid (JA) on the degradation of chlorophyll, broccoli flowers were treated with exogenous methyl jasmonate (MeJA) and diethyldithiocarbamic acid (DIECA). We found a surge of endogenous JA content with the yellowing process, and a significant correlation between JA and chlorophyll content. MeJA treatments led to increased endogenous JA, increased allene oxide cyclase (AOC) activity, and enhanced expression of JA synthesis genes. MeJA caused a stronger reduction in the maximum quantum yield (Fv/Fm), fluorescence decline ratio (Rfd), and total chlorophyll content, advanced the peak of pheide a oxygenase (PAO) activity, and up-regulated the expression of chlorophyll degradation genes. The DIECA treatment resulted in lower endogenous levels of JA, and AOC and 12-oxo-phytodienoic acid reductase (OPR) activity. This study revealed that the potential role of JA on broccoli yellowing is to promote the chlorophyll degradation.

15.
Kaohsiung J Med Sci ; 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31782610

RESUMO

Increasing evidence has indicated the intimate relationship between the gastrointestinal tract and respiratory tract. The microbial ecosystem has been confirmed to share key conceptual features with gut-lung microbiome disorder and dysregulation during chronic obstructive pulmonary disease (COPD) exacerbations. However, the dynamic changes of the gut-lung microbiome during COPD exacerbations and its potential role in disease etiology remain poorly understood. The present study investigated the dynamic changes of gut and lung microorganisms during acute exacerbation of chronic obstructive pulmonary disease (AECOPD). A longitudinal 16S ribosomal DNA survey of the gut and lung microbiome was completed on 90 feces and sputum samples collected from 15 subjects with AECOPD at three visits, which were defined as exacerbation, seven-day stable state. The present analysis revealed a dynamic gut-lung microbiota, where changes appeared to be associated with exacerbation events indicative of specific exacerbation phenotypes. Antibiotic and steroid treatments appeared to have differential effects on the gut-lung microbiome, and the microbiome was associated with disease progression, but not with severity. The abundance and diversity of the microbiome was strongly influenced by the disease progression and therapy. Using culture-independent methods to impact the gut and lung microbiota on AECOPD may be the key to understanding the interactions between the gut and lung, highlighting its potential as a biomarker, and possibly a target for future respiratory therapeutics.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31750262

RESUMO

Gut microbiota composition is known to be associated with the progression of hepatitis B virus (HBV)-related liver cirrhosis in humans, outcome of HBV infection in mice, and seroconversion of HBV e-antigen in nucleot(s)ide analog-treated patients. The dynamic alteration of the gut microbiota following HBV infection is still unknown. In this study, a hydrodynamic injection mouse model mimicking acute or chronic HBV infection in humans with comparable virological and immunological features was used. The composition of gut microbiota in the control mice and mice with acute or chronic HBV infection was analyzed at different time points using the Illumina MiSeq platform. The expression of immune molecules in the colon was detected by real-time polymerase chain reaction. We found that the changes in gut microbiota composition, including the total operational taxonomic unit (OTU) count and Shannon-Weaver index, were significantly delayed in mice with HBV infection. Furthermore, the ratio of Bacteroidetes and Firmicutes was stable in the control mice, whereas remarkable dynamic patterns were observed in mice with HBV infection. Interestingly, the dynamic changes in Lactobacillus and Bifidobacterium were found to differ in acute or chronic HBV infection. In addition, the expression of IFN-γ and PD-L1 in the colon was found to be up-regulated early in mice with acute HBV infection, whereas the expression of PD-L1 in the colon of mice with chronic HBV infection was up-regulated later. These data indicate that HBV infection could hamper the development of the gut microbiota community and dynamically change the gut Firmicutes/Bacteroidetes ratio. These data improve our understanding of the relationship between gut microbiota and HBV infection.

17.
Nanoscale ; 11(45): 22070-22078, 2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31720651

RESUMO

Threshold switches (TSs) are an effective approach for resolving the sneak path problem within a memristor array. VO2 is a promising material for fabricating high-performance TSs. Here we report a single crystal VO2-based TS device with high switching performance. The single crystal monoclinic VO2 channel is obtained by electroforming in a composite vanadium oxide film consisting of VO2, V2O5 and V3O7. The formation mechanism on single crystal VO2 is thoroughly investigated by means of X-ray diffraction, transmission electron microscopy, and Raman spectroscopy. The single crystal VO2-based TS device exhibits better switching performance than the polycrystalline monoclinic VO2 counterpart. The TS device based on a single crystal channel with the (2[combining macron]11) orientation exhibits a steep turn-on voltage slope of <0.5 mV dec-1, a fast switching speed of 23 ns, an excellent endurance over 109 cycles, a high Ion/Ioff ratio of 143 and a low sample-to-sample variance. The enhanced switching performance originates from the single crystal feature and specified crystal orientation.

18.
Cell Prolif ; : e12727, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31747713

RESUMO

OBJECTIVE: Chondrogenesis and endochondral ossification in mandibular condyle play crucial roles in maxillofacial morphogenesis and function. Circadian regulator brain and muscle arnt-like 1 (BMAL1) is proven to be essential for embryonic and postnatal development. The goal of this study was to define the functions of BMAL1 in the embryonic and postnatal growth of mandibular condylar cartilages (MCC). MATERIALS AND METHODS: Micro-CT, TUNEL staining and EdU assay were performed using BMAL1-deficient mice model, and in vitro experiments were performed using rat chondrocytes isolated from MCC. RNA sequencing in mandibular condyle tissues from Bmal1-/- mice and the age-matched wild-type mice was used for transcriptional profiling at different postnatal stages. RESULTS: The expression levels of BMAL1 decrease gradually in MCC. BMAL1 is proved to regulate sequential chondrocyte differentiation, and its deficiency can result in the impairment of endochondral ossification of MCC. RNA sequencing reveals hedgehog signalling pathway is the potential target of BMAL1. BMAL1 regulates hedgehog signalling and affects its downstream cascades through directly binding to the promoters of Ptch1 and Ihh, modulating targets of hedgehog signalling which is indispensable for endochondral ossification. Importantly, the short stature phenotypes caused by BMAL1 deficiency can be rescued by hedgehog signalling activator. CONCLUSIONS: Collectively, these results indicate that BMAL1 plays critical roles on chondrogenesis and endochondral ossification of MCC, giving a new insight on potential therapeutic strategies for facial dysmorphism.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31751199

RESUMO

A Gram-negative, aerobic, non-motile, non-spore-forming and rod-shaped bacterium, named strain LZ-16-2T, was isolated from the phycosphere microbiota of the paralytic shellfish poisoning toxin-producing marine dinoflagellate Alexandrium catenella LZT09. Strain LZ-16-2T grew optimally at 28 °C at pH 6.5 and with 3 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain LZ-16-2T fell within the genus Haliea and was most closely related to Haliea salexigens DSM 19537T, with which the new isolate exhibited 98.5 % 16S rRNA gene sequence similarity. The major respiratory quinone was Q-8. The predominant cellular fatty acids were C17 : 1 ω8c, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c), C17 : 1 ω6c, C11 : 0 3-OH and C17 : 0. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The average nucleotide identity and in silico DNA-DNA genome hybridization relatedness values between strain LZ-16-2T and its closest relative, H. salexigens DSM 19537T, were 92.8 and 55.1 %, respectively. The DNA G+C content was 61.3 mol%. Differential phenotypic properties and phylogenetic distinctiveness distinguished strain LZ-16-2T from all other members of the genus Haliea. On the basis of the polyphasic characterization, strain LZ-16-2T represents a novel species of the genus Haliea, for which the name Haliea alexandrii sp. nov. is proposed. The type strain is LZ-16-2T (=KCTC 62344T=CCTCC AB2017229T).

20.
Pain ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31764385

RESUMO

High frequency stimulation (HFS) of the sciatic nerve has been reported to produce long term potentiation (LTP) and long-lasting pain hypersensitivity in rats. However, the central underlying mechanism remains unclear. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) belongs to a group of electron-transporting transmembrane enzymes that produce reactive oxygen species (ROS). Here we found that NOX2 was upregulated in the lumbar spinal dorsal horn after HFS of the left sciatic nerve, which induced bilateral pain and spinal LTP in both male and female rats. Blocking NOX2 with blocking peptide or shRNA prevented the development of bilateral mechanical allodynia, the induction of spinal LTP, and the phosphorylation of N-methyl-d-aspartate (NMDA) receptor 2B (GluN2B) and nuclear factor kappaB (NF-κB) p65 following HFS. Moreover, NOX2 shRNA reduced the frequency and amplitude of both spontaneous excitatory post synaptic currents (sEPSCs) and miniature excitatory postsynaptic currents (mEPSCs) in laminar II neurons. Furthermore, 8-hydroxyguanine (8-OHG), an oxidative stress marker, was increased in the spinal dorsal horn. Spinal application of ROS scavenger, Phenyl-N-tert-butylnitrone (PBN), depressed the already established spinal LTP. Spinal application of H2O2, one ROS, induced LTP and bilateral mechanical allodynia, increased the frequency and amplitude of sEPSCs in laminar II neurons, and phosphorylated GluN2B and p65 in the dorsal horn. The present study provided electrophysiological and behavioral evidence that NOX2- derived ROS in the spinal cord contributed to persistent mirror-image pain by enhancing the synaptic transmission, which was mediated by increasing presynaptic glutamate release and activation of NMDAR and NF-κB in the spinal dorsal horn.

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