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1.
Biosens Bioelectron ; 147: 111752, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31630033

RESUMO

The sensitive and efficient strategy remains a central challenge for early diagnosis of pathogenic bacteria. Herein, an ultrasensitive electrochemical biosensor was proposed based on the multiple amplification strategy via the 3D DNA walker, rolling circle amplification (RCA) and hybridization chain reaction (HCR) for the accurate detection of Escherichiacoli O157:H7 (E. coli O157:H7). Firstly, the target sequence extracted from E. coli O157:H7 was transformed and amplified by the DNA walker firstly. Subsequently, a large number of transformed nucleic acid sequences were amplified by the RCA reaction. And then, the progress of HCR was triggered by every fragment in RCA products to form a long double-stranded DNA sequence to immobilize electrochemical indicators, generating a significantly enhanced electrochemical signal. As expected, a high sensitivity with a detection limit of 7 CFU/mL was achieved based on the proposed multiple amplification strategy, which is superior to most current methods for E. coli O157: H7 assay. The multiple amplification strategy could be readily expanded for the detection of various pathogenic bacteria, providing a new approach for early diagnosis of pathogenic microorganisms or other diseases.

2.
Sci Total Environ ; : 134839, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31785901

RESUMO

Microplastics (MPs) are widespread in marine and estuarine environments, but the contamination of MPs in mangrove wetlands is relatively unknown. Here, we quantify the presence of MPs in fish collected from Zhanjiang mangrove wetland, the largest mangrove in South China, which provide baseline data on MPs accumulation in fish in mangrove environment as the first evidence in China. MPs were found in 30 out of 32 fish species at an average abundance of 2.83 ±â€¯1.84 items individual-1, ranged from 0.6 to 8.0 items individual-1 in each species. MPs were detected in gills, stomach and intestine, and not found in muscles and livers. Positive relationship was found between MPs abundance and body length or weight of mangrove fish. The dominant polymers identified by micro-FTIR were polyethylene, polyethylene terephthalate, polypropylene and cellophane. MPs consisted primarily of fibers and with the prominent size range of 0.02-1 mm. The body sizes, living habitats and feeding habits of fish are important factors affecting MPs accumulation in different fish species. This study revealed the wide presences of MPs in fish species within a mangrove wetland.

3.
Bioinformatics ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31755899

RESUMO

MOTIVATION: Although genome-wide association studies (GWAS) have deepened our understanding of the genetic architecture of complex traits, the mechanistic links that underlie how genetic variants cause complex traits remains elusive. To advance our understanding of the underlying mechanistic links, various consortia have collected a vast volume of genomic data that enable us to investigate the role that genetic variants play in gene expression regulation. Recently, a collaborative mixed model (CoMM) (Yang et al., 2018a) was proposed to jointly interrogate genome on complex traits by integrating both theGWAS dataset and the expression quantitative trait loci (eQTL) dataset. Although CoMM is a powerful approach that leverages regulatory information while accounting for the uncertainty in using an eQTL dataset, it requires individual-level GWAS data and cannot fully make use of widely available GWAS summary statistics. Therefore, statistically efficient methods that leverages transcriptome information using only summary statistics information from GWAS data are required. RESULTS: In this study, we propose a novel probabilistic model, CoMM-S2, to examine the mechanistic role that genetic variants play, by using only GWAS summary statistics instead of individual-level GWAS data. Similar to CoMM which uses individual-level GWAS data, CoMM-S2 combines two models: the first model examines the relationship between gene expression and genotype, while the second model examines the relationship between the phenotype and the predicted gene expression from the first model. Distinct from CoMM, CoMM-S2 requires only GWAS summary statistics. Using both simulation studies and real data analysis, we demonstrate that even though CoMM-S2 utilizes GWAS summary statistics, it has comparable performance as CoMM, which uses individual-level GWAS data. AVAILABILITY AND IMPLEMENTATION: The implement of CoMM-S2 is included in the CoMM package that can be downloaded from https://github.com/gordonliu810822/CoMM. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

4.
Int J Biol Macromol ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31739015

RESUMO

L. japonica has been used as food and healthy beverage due to the good nutrition. Although the chemical compounds have been extensively studied, polysaccharide compositions remain unclear. In this study, water-soluble polysaccharides of L. japonica were fractionated into one neutral fraction (LJP-N) and four acidic fractions (LJP-A-1 ~ LJP-A-4) by a combination of ion-exchange and gel permeation chromatographies. The structures and antioxidant activities of these factions were determined by HPLC, FT-IR and the radical scavenging activities, anti-hemolysis inhibitory ability, protective effect against DNA damage. Results showed that LJP-N was a starch-like glucan with some arabinogalactan; acidic fractions were all pectic polysaccharide, with the average molecular weights approximately ranging from 19.0 to 383.8 kDa. LJP-A-2 ~ LJP-A-4 were similar to each other, mainly composed of GalA (>50%) with some Gal and Ara residues, while LJP-A-1 mainly composed of Gal and Ara (>70%). LJP-A-3 was defined as HG-type pectic polysacchride, with a trace of RG-I domain by NMR experiment. The antioxidant activity of LJP fractions showed different activities, and LJP-A-3 and LJP-A-4 exhibited noticeable antioxidant activities by six kinds of evaluated methods comparable with others. The results indicated that LJP-A-3 and LJP-A-4 could be used as a potential natural source of antioxidant.

5.
J Am Heart Assoc ; 8(21): e014020, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31665959

RESUMO

Background Blood pressure (BP) guidelines for patients with aortic stenosis or a history of aortic stenosis treated with aortic valve replacement (AVR) match those in the general population, but this extrapolation may not be warranted. Methods and Results Among patients enrolled in the Medtronic intermediate, high, and extreme risk trials, we included those with a transcatheter AVR (n=1794) or surgical AVR (n=1103) who were alive at 30 days. The associations between early (average of discharge and 30 day post-AVR) systolic BP (SBP) and diastolic BP (DBP) measurements and clinical outcomes between 30 days and 1 year were evaluated. Among 2897 patients, after adjustment, spline curves demonstrated an association between lower SBP (<120 mm Hg, representing 21% of patients) and DBP (<60 mm Hg, representing 30% of patients) and increased all-cause and cardiovascular mortality and repeat hospitalization. These relationships were unchanged when patients with moderate-to-severe aortic regurgitation post-AVR were excluded. After adjustment, compared with DBP 60 to <80 mm Hg, DBP 30 to <60 mm Hg was associated with increased all-cause (adjusted hazard ratio 1.62, 95% CI 1.23-2.14) and cardiovascular mortality (adjusted hazard ratio 2.13, 95% CI 1.52-3.00), but DBP 80 to <100 mm Hg was not. Similarly, after adjustment, compared with SBP 120 to <150 mm Hg, SBP 90 to <120 mm Hg was associated with increased all-cause (adjusted hazard ratio 1.63, 95% CI 1.21-2.21) and cardiovascular mortality (adjusted hazard ratio 1.81, 95% CI 1.25-2.61), but SBP 150 to <180 mm Hg was not. Conclusions Lower BP in the first month after transcatheter AVR or surgical AVR is common and associated with increased mortality and repeat hospitalization. Clarifying optimal BP targets in these patients ought to be a priority and may improve patient outcomes. Clinical Trial Registration Information URL: http://www.clinicaltrials.gov. Unique identifiers: NCT01586910, NCT01240902.

6.
Cell Cycle ; 18(24): 3562-3580, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31735119

RESUMO

Osteoporosis and sarcopenia (osteosarcopenia (OS)) are twin-aging diseases. The biochemical crosstalk between muscle and bone seems to play a role in OS. We have previously shown that osteocytes produce soluble factors with beneficial effects on muscle and vice versa. Recently, enhanced FGF9 production was observed in the OmGFP66 osteogenic cell line. To test its role in myogenic differentiation, C2C12 myoblasts were treated with recombinant FGF9. FGF9 as low as 10 ng/mL inhibited myogenic differentiation, suggesting that FGF9 might be a potential inhibitory factor produced from bone cells with effects on muscle cells. FGF9 (10-50 ng/mL) significantly decreased mRNA expression of MyoG and Mhc while increasing the expression of Myostatin. Consistent with the phenotype, RT-qPCR array revealed that FGF9 (10 ng/mL) increased the expression of Icam1 while decreased the expression of Wnt1 and Wnt6 decreased, respectively. FGF9 decreased caffeine-induced Ca2+ release from the sarcoplasmic reticulum (SR) of C2C12 myotubes and reduced the expression of genes (i.e. Cacna1s, RyR2, Naftc3) directly associated with intracellular Ca2+ homeostasis. Myogenic differentiation in human skeletal muscle cells was similarly inhibited by FGF9 but required higher doses of 200 ng/mL FGF9. FGF9 was also shown to stimulate C2C12 myoblast proliferation. FGF2 and the FGF9 subfamily members FGF16 and FGF20 also inhibited C2C12 myoblast differentiation and enhanced proliferation. Intriguingly, the differentiation inhibition was independent of proliferation enhancement. These findings suggest that FGF9 may modulate myogenesis via a complex signaling mechanism.

7.
Cancer Commun (Lond) ; 39(1): 80, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31775884

RESUMO

BACKGROUND: Clinical outcome of adrenocortical carcinoma (ACC) varies because of its heterogeneous nature and reliable prognostic prediction model for adult ACC patients is limited. The objective of this study was to develop and externally validate a nomogram for overall survival (OS) prediction in adult patients with ACC after surgery. METHODS: Based on the data from the Surveillance Epidemiology, and End Results (SEER) database, adults patients diagnosed with ACC between January 1988 and December 2015 were identified and classified into a training set, comprised of 404 patients diagnosed between January 2007 and December 2015, and an internal validation set, comprised of 318 patients diagnosed between January 1988 and December 2006. The endpoint of this study was OS. The nomogram was developed using a multivariate Cox proportional hazards regression algorithm in the training set and its performance was evaluated in terms of its discriminative ability, calibration, and clinical usefulness. The nomogram was then validated using the internal SEER validation, also externally validated using the Cancer Genome Atlas set (TCGA, 82 patients diagnosed between 1998 and 2012) and a Chinese multicenter cohort dataset (82 patients diagnosed between December 2002 and May 2018), respectively. RESULTS: Age at diagnosis, T stage, N stage, and M stage were identified as independent predictors for OS. A nomogram incorporating these four predictors was constructed using the training set and demonstrated good calibration and discrimination (C-index 95% confidence interval [CI], 0.715 [0.679-0.751]), which was validated in the internal validation set (C-index [95% CI], 0.672 [0.637-0.707]), the TCGA set (C-index [95% CI], 0.810 [0.732-0.888]) and the Chinese multicenter set (C-index [95% CI], 0.726 [0.633-0.819]), respectively. Encouragingly, the nomogram was able to successfully distinguished patients with a high-risk of mortality in all enrolled patients and in the subgroup analyses. Decision curve analysis indicated that the nomogram was clinically useful and applicable. CONCLUSIONS: The study presents a nomogram that incorporates clinicopathological predictors, which can accurately predict the OS of adult ACC patients after surgery. This model and the corresponding risk classification system have the potential to guide therapy decisions after surgery.

8.
Aging (Albany NY) ; 11(22): 10154-10166, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31740624

RESUMO

Cervical squamous cell carcinoma (CSCC) is one of the most commonly occurring gynecological malignancies. Because CSCC is a biologically heterogeneous disease, its prognosis varies. Therefore, identifying prognostic biomarkers that reflect its biological heterogeneity could lead to better interventions for patients with a poor prognosis. This study used the ESTIMATE algorithm to identify immune related prognostic genes within the tumor microenvironment of CSCC. The results revealed that high immune scores were associated with better overall survival (P = 0.029). Differential expression analysis revealed 384 intersection genes influencing both the immune and stromal scores. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses showed the 384 intersection genes to be mainly enriched for T cell activation, the region of the membrane, carbohydrate binding, and cytokine-cytokine receptor interaction. Among them, 149 immune genes were predictive of overall survival in CSCC. These findings provide a more comprehensive understanding of immune genes within the tumor microenvironment as well as a list of immune genes prognostic in CSCC.

9.
Taiwan J Obstet Gynecol ; 58(6): 859-863, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31759543

RESUMO

OBJECTIVE: We present detection of a familial 1q21.1 microdeletion and concomitant CHD1L mutation in a fetus with oligohydramnios and bilateral renal dysplasia on prenatal ultrasound. CASE REPORT: A 37-year-old, primigravid woman was referred for level II ultrasound examination at 16 weeks of gestation because of oligohydramnios. The parents were phenotypically normal, and there were no congenital malformations in the family. Prenatal ultrasound at 17 weeks of gestation revealed a fetus with fetal growth biometry equivalent to 16 weeks, oligohydramnios with an amniotic fluid index (AFI) of 1.4 cm and bilateral renal dysplasia without sonographic demonstration of bilateral renal arteries. The pregnancy was subsequently terminated, and a 137-g fetus was delivered without characteristic facial dysmorphism. Postnatal cytogenetic analysis of the umbilical cord and parental bloods revealed normal karyotypes. However, array comparative genomic hybridization (aCGH) analysis on the DNA extracted from the umbilical cord revealed a 2.038-Mb microdeletion of 1q21.1-q21.2 encompassing 11 [Online Mendelian Inheritance in Man (OMIM)] genes of PRKAB2, FMO5, CHD1L, BCL9, ACP6, GJA5, GJA8, GPR89B, NBPF14, TRN-GTT2-1 and NBPF20. The mother was found to carry the same microdeletion. A missense mutation of c.2353T > G, p.Ser785Ala in CHD1L was detected in the umbilical cord. The father was found to carry a heterozygous mutation of c.2353T > G, p.Ser785Ala in CHD1L. CONCLUSION: Fetuses with a 1q21.1 microdeletion and concomitant CHD1L mutation may present oligohydramnios and bilateral renal dysplasia on prenatal ultrasound.

10.
Protein Pept Lett ; 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31721688

RESUMO

BACKGROUND: Neuropeptides are a class of bioactive peptides produced from neuropeptide precursors through a series of extremely complex processes, mediating neuronal regulations in many aspects. Accurate identification of cleavage sites of neuropeptide precursors is of great significance for the development of neuroscience and brain science. OBJECTIVE: With the explosive growth of neuropeptide precursor data, it is pretty much needed to develop bioinformatics methods for predicting neuropeptide precursors' cleavage sites quickly and efficiently. METHOD: We started with processing the neuropeptide precursor data from SwissProt and NueoPedia into two sets of data, training dataset and testing dataset. Subsequently, six feature extraction schemes were applied to generate different feature sets and then feature selection methods were used to find the optimal feature set of each. Thereafter the support vector machine was utilized to build models for different feature types. Finally, the performance of models were evaluated with the independent testing dataset. RESULTS: Six models are built through support vector machine. Among them the enhanced amino acid composition-based model reaches the highest accuracy of 91.60% in the 5-fold cross validation. When evaluated with independent testing dataset, it also showed an excellent performance with a high accuracy of 90.37% and Area under Receiver Operating Characteristic curve up to 0.9576. CONCLUSION: The performance of the developed model was decent. Moreover, for users' convenience, an online web server called NeuroCS is built, which is freely available at http://i.uestc.edu.cn/NeuroCS/dist/index.html#/. NeuroCS can be used to predict neuropeptide precursors' cleavage sites effectively.

11.
Oncogene ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31740781

RESUMO

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKIs) significantly prolong the survival time of non-small-cell lung cancer (NSCLC) patients with EGFR-activating mutations, but resistance develops universally. Activation of the phosphatidyl inositol-3 kinase (PI3K)/AKT signaling pathway and phenotypic alterations in epithelial-mesenchymal transition (EMT) are both mechanisms of acquired resistance to EGFR-TKIs. However, the mechanisms underlying this resistance remain unclear. In this study, EHD1 depletion significantly increased NSCLC cell sensitivity to EGFR-TKI, which was accompanied by EMT reversal. Microarray analysis showed that the PTEN/PI3K/AKT signaling pathway is a crucial pathway regulated by EHD1. Moreover, a PTEN inhibitor abolished EHD1 shRNA regulation of EGFR-TKI sensitivity, EMT, and cancer progression. Mass spectrometry showed that TUBB3 is a novel EHD1-interacting protein. EHD1 modulated microtubule stability by interacting with TUBB3. Furthermore, TUBB3 depletion significantly attenuated EHD1-induced EGFR-TKI resistance and EMT. Bioinformatics analysis revealed that EHD1 is significantly associated with the gene set, "Cellular Response to Interleukin-1ß (IL-1ß)". As expected, treatment with IL-1ß led to increased expression of EHD1, activation of PTEN/PI3K/AKT signaling, and induction of EMT in NSCLC cells. In patient specimens, EHD1 was highly expressed in EGFR-TKI-refractory specimens. EHD1 was positively associated with TUBB3 and IL-1R1 but negatively associated with PTEN. In addition, targeting the IL-1ß/EHD1/TUBB3 axis mitigated cancer progression by inhibiting cell proliferation and metastasis and promoting apoptosis. Our study demonstrates the involvement of the IL-1ß/EHD1/TUBB3 axis in EGFR-TKI resistance and provides a potential therapeutic approach for treating patients with NSCLC that has acquired EGFR-TKI resistance.

12.
Interdiscip Sci ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31741225

RESUMO

The argonaute protein (Ago) exists in almost all organisms. In eukaryotes, it functions as a regulatory system for gene expression. In prokaryotes, it is a type of defense system against foreign invasive genomes. The Ago system has been engineered for gene silencing and genome editing and plays an important role in biological studies. With an increasing number of genomes and proteomes of various microbes becoming available, computational tools for identifying and annotating argonaute proteins are urgently needed. We introduce AGONOTES (Argonaute Notes). It is a web service especially designed for identifying and annotating Ago. AGONOTES uses the BLASTP similarity search algorithm to categorize all submitted proteins into three groups: prokaryotic argonaute protein (pAgo), eukaryotic argonaute protein (eAgo), and non-argonaute protein (non-Ago). Argonaute proteins can then be aligned to the corresponding standard set of Ago sequences using the multiple sequence alignment program MUSCLE. All functional domains of Ago can further be curated from the alignment results and visualized easily through Bio::Graphic modules in the BioPerl bundle. Compared with existing tools such as CD-Search and available databases such as UniProt and AGONOTES showed a much better performance on domain annotations, which is fundamental in studying the new Ago. AGONOTES can be freely accessed at http://i.uestc.edu.cn/agonotes/. AGONOTES is a friendly tool for annotating Ago domains from a proteome or a series of protein sequences.

13.
Sci Total Environ ; 699: 134342, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31678885

RESUMO

Heterogeneous photodegradation is limited at high catalyst concentrations because of the scattering and reflection of the particulate catalysts. To further improve the efficiency of photodegradation and the use of space in photoreactors at high catalyst concentrations, Ga3+ was doped into Zn2SiO4 to introduce positively charged traps to capture photo-generated electrons and, thus, achieve long lifetime charge separation. In this strategy, Zn2SiO4:Ga3+ was obtained as a two-in-one (persistent luminescence and catalysis) persistent photocatalyst for the efficient photodegradation of a household insecticide, permethrin. Zn2SiO4:Ga3+ possesses an UV afterglow property. Zn2SiO4:Ga3+ can store UV irradiation energy as long lifetime separated electron/hole pairs at the solution surface and then deliver this energy deep into the bulk of the solution, thus taking full advantage of the photoreactor. High catalyst concentrations are preferred for improving the persistent photodegradation efficiency. The UV persistent photocatalytic strategy and the persistent Zn2SiO4:Ga3+ catalyst are significant for designing fast photocatalytic reactors with high catalyst concentrations.

14.
Sci Rep ; 9(1): 15973, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31685957

RESUMO

Jatropha curcas, an economically important biofuel feedstock with oil-rich seeds, has attracted considerable attention among researchers in recent years. Nevertheless, valuable information on the yield component of this plant, particularly regarding ovule development, remains scarce. In this study, transcriptome profiles of anther and ovule development were established to investigate the ovule development mechanism of J. curcas. In total, 64,325 unigenes with annotation were obtained, and 1723 differentially expressed genes (DEGs) were identified between different stages. The DEG analysis showed the participation of five transcription factor families (bHLH, WRKY, MYB, NAC and ERF), five hormone signaling pathways (auxin, gibberellic acid (GA), cytokinin, brassinosteroids (BR) and jasmonic acid (JA)), five MADS-box genes (AGAMOUS-2, AGAMOUS-1, AGL1, AGL11, and AGL14), SUP and SLK3 in ovule development. The role of GA and JA in ovule development was evident with increases in flower buds during ovule development: GA was increased approximately twofold, and JA was increased approximately sevenfold. In addition, the expression pattern analysis using qRT-PCR revealed that CRABS CLAW and AGAMOUS-2 were also involved in ovule development. The upregulation of BR signaling genes during ovule development might have been regulated by other phytohormone signaling pathways through crosstalk. This study provides a valuable framework for investigating the regulatory networks of ovule development in J. curcas.

15.
Respir Res ; 20(1): 255, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31718614

RESUMO

BACKGROUND: Bronchopulmonary dysplasia (BPD) is characterized by alveolar simplification and disordered angiogenesis. Stromal derived factor-1 (SDF-1) is a chemokine which modulates cell migration, proliferation, and angiogenesis. Here we tested the hypothesis that intra-tracheal (IT) administration of a naked plasmid DNA expressing SDF-1 would attenuate neonatal hyperoxia-induced lung injury in an experimental model of BPD, by promoting angiogenesis. DESIGN/METHODS: Newborn Sprague-Dawley rat pups (n = 18-20/group) exposed to room air (RA) or hyperoxia (85% O2) from postnatal day (P) 1 to 14 were randomly assigned to receive IT a naked plasmid expressing SDF-1, JVS-100 (Juventas Therapeutics, Cleveland, Ohio) or placebo (PL) on P3. Lung alveolarization, angiogenesis, inflammation, vascular remodeling and pulmonary hypertension (PH) were assessed on P14. PH was determined by measuring right ventricular systolic pressure (RVSP) and the weight ratio of the right to left ventricle + septum (RV/LV + S). Capillary tube formation in SDF-1 treated hyperoxia-exposed human pulmonary microvascular endothelial cells (HPMEC) was determined by matrigel assay. Data is expressed as mean ± SD and analyzed by two-way ANOVA. RESULTS: Exposure of neonatal pups to 14 days of hyperoxia decreased lung SDF-1 gene expression. Moreover, whilst hyperoxia exposure inhibited capillary tube formation in HPMEC, SDF-1 treatment increased tube length and branching in HPMEC. PL-treated hyperoxia-exposed pups had decreased alveolarization and lung vascular density. This was accompanied by an increase in RVSP, RV/LV + S, pulmonary vascular remodeling and inflammation. In contrast, IT JVS-100 improved lung structure, reduced inflammation, PH and vascular remodeling. CONCLUSIONS: Intratracheal administration of a naked plasmid expressing SDF-1 improves alveolar and vascular structure in an experimental model of BPD. These findings suggest that therapies which modulate lung SDF-1 expression may have beneficial effects in preterm infants with BPD.

16.
Adv Exp Med Biol ; 1101: 91-122, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31729673

RESUMO

Peripheral nervous system, widely spread in the whole body, is the important bridge for the transmission of neural signals. Signals from the central nervous system (brain and spinal cord) are transmitted to different parts of the body by the peripheral nerves, while along the way they also feedback all kinds of sensory information. Certain level of information integration and processing also occurs in the system. It has been shown that neural signals could be extracted from the distal end of the stump, indicating that the bridge is still effective after limb damage or amputation, which is the neurophysiological basis for the research and development of peripheral nerve interface for the prosthetic system.


Assuntos
Nervos Periféricos , Transdução de Sinais , Sistema Nervoso Central , Humanos , Regeneração Nervosa , Nervos Periféricos/fisiologia , Próteses e Implantes , Medula Espinal
17.
Biomolecules ; 9(12)2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31771142

RESUMO

In this work, a monoclonal antibody-based indirect competitive enzyme-linked immunosorbent assay (icELISA) was established to detect tylosin and tilmicosin in milk and water samples. A sensitive and specific monoclonal antibody was prepared by rational designed hapten, which was achieved by directly oxidizing the aldehyde group on the side chain of tylosin to the carboxyl group. Under the optimized conditions, the linear range of icELISA for tylosin and tilmicosin were 1.3 to 17.7 ng/mL and 2.0 to 47.4 ng/mL, with half-maximal inhibition concentration (IC50) values of 4.7 and 9.6 ng/mL, respectively. The cross-reactivity with other analogues of icELISA was less than 0.1%. The average recoveries of icELISA for tylosin and tilmicosin ranged from 76.4% to 109.5% in milk and water samples. Besides, the detection results of icELISA showed good correlations with HPLC-MS/MS. The proposed icELISA was satisfied for rapid and specific screening of tylosin and tilmicosin residues in milk and water samples.

18.
New Phytol ; 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31705812

RESUMO

Some medicinal plants of the Solanaceae produce pharmaceutical tropane alkaloids (TAs), such as hyoscyamine and scopolamine. Littorine is a key biosynthetic intermediate in the hyoscyamine and scopolamine biosynthetic pathways. However, the mechanism underlying littorine formation from the precursors phenyllactate and tropine is not completely understood. Here, we report the elucidation of littorine biosynthesis through a functional genomics approach and functional identification of two novel biosynthesis genes that encode phenyllactate UDP-glycosyltransferase (UGT1) and littorine synthase (LS). UGT1 and LS are highly and specifically expressed in Atropa belladonna secondary roots. Suppression of either UGT1 or LS disrupted the biosynthesis of littorine and its TA derivatives (hyoscyamine and scopolamine). Purified His-tagged UGT1 catalysed phenyllactate glycosylation to form phenyllactylglucose. UGT1 and LS co-expression in tobacco leaves led to littorine synthesis if tropine and phenyllactate were added. This identification of UGT1 and LS provides the missing link in littorine biosynthesis. The results pave the way for producing hyoscyamine and scopolamine for medical use by metabolic engineering or synthetic biology.

19.
Exp Cell Res ; : 111740, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31756312

RESUMO

Advanced gastric cancer (GC) is aggressive with a high mortality rate. Rhesus family, C glycoprotein (RhCG) participates in tumor progression in many cancers, however its function in GC is still unknown. Here, we showed that RhCG was overexpressed in GC tissues at mRNA (P = 0.036) and protein levels (P < 0.05) compared with normal tissues. High RhCG level was correlated with poor differentiation (P = 0.037), TNM stage (P < 0.001), high HER-2 level (P = 0.018) and worse prognosis (P < 0.001). Cox proportional hazard model indicated that RhCG level was an independent prognostic biomarker. RhCG knockdown significantly decreased pHi and impeded tumor cellular proliferation, migration and invasion and repressed ß-catenin and c-myc expression in GC cells. Moreover, GC cells with high RhCG level had reduced oxaliplatin efficacy suggesting a role for RhCG as a therapeutic target for GC. Our findings revealed a function of RhCG in cancer pathogenesis, invasion and metastasis in human GC. We suggest that RhCG act may as a novel prognostic indicator and a therapeutic target for gastric adenocarcinoma.

20.
Nat Commun ; 10(1): 5321, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31757965

RESUMO

Surface-enhanced Raman spectroscopy (SERS) sensing of DNA bases by plasmonic nanopores could pave a way to novel methods for DNA analyses and new generation single-molecule sequencing platforms. The SERS discrimination of single DNA bases depends critically on the time that a DNA strand resides within the plasmonic hot spot. In fact, DNA molecules flow through the nanopores so rapidly that the SERS signals collected are not sufficient for single-molecule analysis. Here, we report an approach to control the residence time of molecules in the hot spot by an electro-plasmonic trapping effect. By directly adsorbing molecules onto a gold nanoparticle and then trapping the single nanoparticle in a plasmonic nanohole up to several minutes, we demonstrate single-molecule SERS detection of all four DNA bases as well as discrimination of single nucleobases in a single oligonucleotide. Our method can be extended easily to label-free sensing of single-molecule amino acids and proteins.

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