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1.
Medicine (Baltimore) ; 98(45): e17733, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31702624

RESUMO

BACKGROUND: Cervical radiculopathy (CR), which is most often stems from degenerative disease in the cervical spine, has increasingly become a common and frequently occurring disease in clinic due to the popularity of electronic products, such as computes and cell phones. Some studies have shown that exercise or exercise combined with other treatments can effectively decrease pain and improve functional status. The objective was to analyze the effects of exercise for treating patients with CR. METHODS: Seven databases were searched from inception to December 2018. Randomized controlled trials involving exercise alone or exercise combined with conventional treatment were enrolled. Data were pooled after trials quality assessment for meta-analysis. Outcomes were pain (visual analog scale [VAS]), quality of life (12-short form health survey, 36-short form health survey), and physical function accessed by neck disability index (NDI). RESULTS: Ten studies involving 871 participants with CR were included. Meta-analysis revealed that compared with control group, there was a reduction in VAS (standardized mean difference = -0.89; 95% confidence interval [CI]: -1.34 to -0.44; Z = 3.89; P < .001). There was also an improvement of NDI (mean difference = -3.60; 95% CI: -6.27 to -0.94; Z = 2.65; P = .008)]. Additionally, although the results of subgroup analyses were changed due to the paucity of the quantity and quality of the included studies. The pooled results were verified to be stable by sensitivity analyses. Besides, the grading of recommendations assessment, development, and evaluation level of evidence is low for each outcome. CONCLUSION: Exercise alone or exercise plus other treatment may be helpful to patients with CR. However, exercise option should be carefully considered for each patient with CR in accordance with their different situations. Large-scale studies using proper methodology are recommended.


Assuntos
Terapia por Exercício/métodos , Radiculopatia/reabilitação , Humanos , Medição da Dor , Qualidade de Vida , Resultado do Tratamento , Escala Visual Analógica
2.
Anal Chim Acta ; 1091: 127-134, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31679566

RESUMO

Ultraviolet B (UVB) irradiation induces the generation of reactive oxygen species (ROS) and causes damages to human skin. The depletion of glutathione (GSH) to scavenge ROS can protect skin cells from oxidative damage. However, little is known about the concentration level changes of cysteine (Cys), a precursor of GSH in skin cells after exposure to UVB irradiation. Herein, phenyl doped graphitic carbon nitride nanosheets-Au nanoparticles nanocomposite was prepared by in situ deposition of Au nanoparticles on the surface of phenyl doped graphitic carbon nitride nanosheets and showed a turn-on fluorescence response toward Cys over homocysteine, glutathione under physiological conditions. In the presence of Cys, remarkable enhancement of green fluorescence was observed. This nanocomposite was successfully applied for fluorescence imaging of Cys in human skin epidermal cells and monitoring the changes of Cys concentration level under the oxidative stress upon exposure to UVB irradiation in keratinocytes. It was found that the concentration of Cys was increased in the initial period after exposure to UVB irradiation and then gradually decreased to the normal level for the synthesis of GSH to defense the oxidative stress. Our result helps to understand the physiological function of Cys in human skin cells under UVB exposure.

3.
Am J Transplant ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31710417

RESUMO

Ex vivo lung perfusion (EVLP) with pharmacological reconditioning may increase donor lung utilization for transplantation (LTx). 3-aminobenzamide (3-AB), an inhibitor of poly(ADP-ribose) polymerase (PARP), reduces ex-vivo lung injury in rat lungs damaged by warm ischemia. Here we determined the effects of 3-AB reconditioning on graft outcome after LTx. 3 groups of donor lungs were studied: Control (Ctrl): 1h Warm ischemia (WI)+3h cold ischemia (CI)+LTx; EVLP: 1 h WI+3h EVLP+LTx; EVLP+3-AB: 1H WI+3h EVLP with 3-AB (1mg. ml-1 )+LTx. Two hours after LTx, we determined lung graft compliance, edema, histology, neutrophil counts in bronchoalveolar lavage (BAL), mRNA levels of adhesion molecules within the graft, as well as concentrations of Interleukin-6 and 10 (IL-6, IL-10) in BAL and plasma. 3-AB reconditioning during EVLP improved compliance and reduced lung edema, neutrophil infiltration and the expression of adhesion molecules within the transplanted lungs. 3-AB also attenuated the IL-6/IL-10 ratio in BAL and plasma, supporting an improved balance between pro- and anti-inflammatory mediators. Thus, 3-AB reconditioning during EVLP of rat lung grafts damaged by warm ischemia markedly reduces inflammation, edema and physiological deterioration after LTx, supporting the use of PARP inhibitors for the rehabilitation of damaged lungs during EVLP.

5.
Pathol Res Pract ; 215(12): 152726, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31708373

RESUMO

BACKGROUND: Increasing evidence shows microRNA-451 plays a crucial role in various tumors, but there is inconsistency. The aim of this study was to explore the prognostic role of miR-451 in various tumors. METHODS: Online PubMed, EMBASE, Web of Science, and the Cochrane library database were searched through February 2019. Hazard ratios (HRs) were extracted and used to describe the association between expression of microRNA-451 and survival outcome, and the correlation between microRNA-451 and clinicopathologic features were described by pooled odds ratios (ORs). RESULTS: Sixteen retrospective studies containing 2122 patients were incorporated in this meta-analysis. High expression of miR-451 was considered statistically associated with prolonged overall survival (OS) (HR = 0.62, 95% CI 0.49-0.80, p < 0.001) as well as RFS/DFS (HR = 0.55, 95% CI 0.42-0.71, p < 0.001) compared with low expression of miR-451. Besides, the pooled ORs revealed significant association between high expression of miR-451 with lymph node invasion (yes vs. no) (OR = 0.64, 95% CI 0.46-0.90, P = 0.01), tumor diameter (big vs. small) (OR = 0.77, 95% CI 0.60-0.97, P = 0.028) and tumor stage (III + IV vs. I + II) (OR = 0.62, 95% CI 0.42-0.93, P = 0.019). CONCLUSION: MicroRNA-451 may serve as a promising clinical prognostic biomarker in various carcinomas.

6.
Sci Rep ; 9(1): 14489, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601966

RESUMO

We introduce a novel concept for the design of functional surfaces of materials: Spatial surface charge engineering. We exploit the concept for an all-solid-state, epitaxial InN/InGaN-on-Si reference electrode to replace the inconvenient liquid-filled reference electrodes, such as Ag/AgCl. Reference electrodes are universal components of electrochemical sensors, ubiquitous in electrochemistry to set a constant potential. For subtle interrelation of structure design, surface morphology and the unique surface charge properties of InGaN, the reference electrode has less than 10 mV/decade sensitivity over a wide concentration range, evaluated for KCl aqueous solutions and less than 2 mV/hour long-time drift over 12 hours. Key is a nanoscale charge balanced surface for the right InGaN composition, InN amount and InGaN surface morphology, depending on growth conditions and layer thickness, which is underpinned by the surface potential measured by Kelvin probe force microscopy. When paired with the InN/InGaN quantum dot sensing electrode with super-Nernstian sensitivity, where only structure design and surface morphology are changed, this completes an all-InGaN-based electrochemical sensor with unprecedented performance.

7.
J Mater Chem B ; 7(36): 5432-5448, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31482932

RESUMO

Graphitic carbon nitride quantum dots (g-CNQDs) have attracted much attention for biomedical applications by virtue of their good biocompatibility, stable fluorescence, high quantum yield, and nontoxicity. On the basis of understanding the intrinsic properties and structural features in the intriguing system, enormous efforts have been devoted to optimizing synthetic methods and structures of g-CNQDs. A vast number of studies have also been pursued to discuss the potential applications of g-CNQDs in biomedical areas for biosensing, bioimaging, drug delivery and theranostics. In this review, we summarize the recent advances and applications and address the future challenges and opportunities of these g-CNQDs in the biomedical field.

8.
J Dairy Sci ; 102(12): 10814-10824, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563315

RESUMO

An aptamer-based strategy was developed for qualitative and quantitative analysis of viable Lactobacillus casei in dairy products. Three highly specific aptamers for L. casei were obtained using systematic evolution of ligands by exponential enrichment protocol using the whole bacterium cell as the target (cell-SELEX) facilitated by polyethyleneglycol and chitosan modified graphene oxide and complementary ring-mediated rolling circle amplification. Two aptamers, one for separating and enriching the L. casei cells and the other for generating fluorescence signals, were employed to develop an aptamer-based strategy, which was demonstrated for the selective detection of L. casei in commercial dairy drinks, with a dynamic range of 105 to 109 cfu/mL. Viable and nonviable L. casei cells could be discriminated based on the significant difference in fluorescence intensity. This established strategy is of high selectivity and sensitivity, and can be used for rapid analysis of viable L. casei in quality control and food surveillance areas.

9.
Adv Clin Exp Med ; 28(8): 1059-1066, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31414732

RESUMO

BACKGROUND: It is well-known that severe acute pancreatitis (SAP) due to infection is mainly caused by intestinal bacterial translocation. The intestinal barrier is tasked with preventing intestinal pathogenic bacteria and toxins from reaching the parenteral tissues through the intestinal wall. Therefore, maintaining intestinal barrier function may be the key to preventing damage from acute pancreatitis (AP). The phosphatidylinositol 3-kinase/protein kinase B pathway (PI3K/PKB) plays a role in AP. However, the exact effect of PI3K/PKB on injury associated with SAP has not yet been found. OBJECTIVES: The present study was aimed at investigating the impact of wortmannin (WT), a PI3K/PKB inhibitor, on intestinal barrier function in SAP rats. MATERIAL AND METHODS: The rats were divided into 3 groups: 1) the Sham Surgery group (SS), whose duodenum and pancreas were flipped 3 times (n = 18); 2) the pancreatitis group (SAP), who were injected through retrograde pancreatic duct injection with 5% sodium taurocholate (n = 18); and 3) the WSAP intervention group (SAP+WT). Serum alpha-amylase levels, plasma endogenous endotoxin, hematoxylin-eosin (H&E) staining, intestinal mucosa electron microscopy, intestinal permeability, and expression of p-PKB (phosphorylated protein kinase B) were measured. RESULTS: In our findings under an electron microscope, the SAP group presented cell edema and mitochondrial vacuolated degeneration, sparsely arranged microvilli, tight junction damage, and widening, while the WSAP group exhibited less change and lower pancreas scores (7.4 ±1.14, 10.2 ±1.48 and 12.0 ±1.58 for 3 h, 6 h and 12 h, respectively) (p < 0.05). Furthermore, the plasma endogenous endotoxin levels and Evans blue content of the WSAP group was significantly lower at all timepoints than in the SAP group (p < 0.05). Western blotting showed that p-PKB expression was lower in the WSAP group than in the SAP group (p < 0.05). Our study suggests that WT relieves intestinal permeability changes in SAP rats and may be dose-dependent. CONCLUSIONS: The PI3K/PKB signal pathway may involve SAP-related intestinal injuries and WT may relieve SAP intestinal injuries through the PI3K/PKB pathway.


Assuntos
Mucosa Intestinal , Pancreatite , Fosfatidilinositol 3-Quinases , Wortmanina , Doença Aguda , Animais , Mucosa Intestinal/efeitos dos fármacos , Pancreatite/tratamento farmacológico , Pancreatite/metabolismo , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/fisiologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Wortmanina/farmacologia
10.
J Environ Manage ; 249: 109393, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450200

RESUMO

The first commitment period of the Kyoto Protocol came to an end in 2012 and more developing countries began to participate in the new phase of world carbon emission reduction. Kazakhstan is an important energy export country and a pivot of the "Belt and Road Initiative" (BRI). Despite its emissions are relatively small compared with huge emitters such as China and the US, Kazakhstan also faces great pressure in terms of CO2 emission reduction and green development. Accurately accounting CO2 emissions in Kazakhstan from both production and consumption perspectives is the first step for further emissions control actions. This paper constructs production-based CO2 emission inventories for Kazakhstan from 2012 to 2016, and then further analyses the demand-driven emissions within the domestic market and international trade (exports and imports) using environmentally extended input-output analysis. The production-based inventory includes 43 energy products and 30 sectors to provide detailed data for CO2 emissions in Kazakhstan. The consumption-based accounting results showed that certain sectors like construction drive more emissions and that the fuel consumption in different sectors varies. Furthermore, Russia and China are major consumers of Kazakhstan's energy and associated emissions, with the construction sector playing the most important role in it. The results suggested that both technology and policy actions should be taken into account to reduce CO2 emissions and that the BRI is also a good chance for Kazakhstan to develop a "Green Economy".


Assuntos
Dióxido de Carbono , Comércio , China , Internacionalidade , Cazaquistão
11.
Brain Behav Immun ; 82: 45-62, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31376499

RESUMO

A chronic neuroinflammatory response has been considered as a critical pathogenesis promoting neurodegenerative progression in Alzheimer's disease (AD). During neuroinflammatory process, microglia are excessively activated and simultaneously release numerous pro-inflammatory mediators that cause synaptic dysfunction in the forebrain prior to neuronal degeneration and memory deficits in AD. Thus, prevention of neuroinflammation-mediated synaptic dysfunction may be a potential therapeutic approach against neurodegenerative disorders. Trans-cinnamaldehyde (TCA) is a primary bioactive component derived from the stem bark of Cinnamomum cassia, and it possesses potent anti-inflammatory and neuroprotective activities in in vivo and in vitro experiments. However, the in-depth molecular mechanisms of TCA underlying anti-neuroinflammatory and neuroprotective effects on memory deficits in AD are still unclear. The presenilin 1 and 2 conditional double knockout (PS cDKO) mice exhibit AD-like phenotypes including obvious neuroinflammatory responses and synaptic dysfunction and memory deficits. Here, PS cDKO were used to evaluate the potential neuroprotective effects of TCA against neuroinflammation-mediated dementia by performing behavioral tests, electrophysiological recordings and molecular biology analyses. We observed that TCA treatment reversed abnormal expression of synaptic proteins and tau hyperphosphorylation in the hippocampus and prefrontal cortex of PS cDKO mice. TCA treatment also ameliorated NMDA receptor (NMDAR) dysfunction including impaired NMDAR-mediated responses and long-term potentiation (LTP) induction in the hippocampus of PS cDKO mice. Moreover, TCA possesses an ability to suppress neuroinflammatory responses by diminishing microglial activation and levels of pro-inflammatory mediators in the hippocampus and prefrontal cortex of PS cDKO mice. Importantly, improving NMDAR dysfunction and memory deficits of PS cDKO mice was due to the inhibition of neuroinflammatory responses through TCA's interruptive effect on the nuclear factor kappa B (NF-κB) signaling pathway. Therefore, TCA may be a potential anti-neuroinflammatory agent for deterring neurodegenerative progression of AD.

12.
Medicine (Baltimore) ; 98(35): e16975, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31464943

RESUMO

BACKGROUND: Significant functional limitations and disabilities are common presenting complaints for people suffering from cervical radiculopathy. Exercise is a common conservative treatment for this disease. Therefore, we conducted a systematic review and meta-analysis to explore the efficacy of exercise in the treatment of cervical radiculopathy. METHODS: A systematic literature search for studies will be performed in 7 databases, including PubMed, Web of Science, Embase, the Cochrane Library, the Chinese National Knowledge Infrastructure Database (CNKI), Wanfang database, and VIP database. The methodological quality of the included studies using the risk bias assessment tool of Cochrane and the level of evidence for results are assessed by the GRADE method. Statistical analysis is conducted with Revman 5.3. RESULTS: This systematic review and meta-analysis will provide a synthesis of existed evidences for exercise on cervical radiculopathy. CONCLUSION: The conclusion of this study will provide evidence to assess effectiveness of exercise on cervical radiculopathy, which can further guide clinical decision-making. PROSPERO REGISTRATION NUMBER: CRD42019121886.


Assuntos
Vértebras Cervicais , Exercício/fisiologia , Radiculopatia/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa
13.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(6): 777-780, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31315741

RESUMO

OBJECTIVE: Infectious and inflammatory diseases are important diseases threatening human health. Without timely control, a series of complications will occur in patients, such as sepsis, inflammatory factor storm, and even lead to death. It has been found that cytochrome P4501A1 (CYP1A1) plays a key role in the development of infectious and inflammatory diseases through aromatic hydrocarbon receptor (AhR) dependent and non-dependent pathways in different cells and organs induced by different substances. The non AhR dependent regulatory mechanism of CYP1A1 and the different roles of CYP1A1 in infection and inflammation is reviewed in order to provide reference for further research on the relationship between CYP1A1 and infection and inflammation.


Assuntos
Citocromo P-450 CYP1A1/metabolismo , Infecção/etiologia , Inflamação/etiologia , Receptores de Hidrocarboneto Arílico/metabolismo , Humanos
14.
Biochimie ; 163: 137-141, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31181235

RESUMO

RNA amplification has extensive applications on biochemistry and its related fields. Here, we present an isothermal strategy named rolling circle reverse transcription-mediated RNA amplification (RCRT-MRA) to amplify small RNAs with accurate length and sequence. The target RNA and complementary DNA were circularized to serve as amplicons replicated via the rolling circle mechanism. The transcription product consisting of tandemly repeated RNA units, was monomerized by site-specific cleavage to generate amplified RNA with authentic length and sequence. T4 DNA ligase was chosen to circularize RNA template for its high efficiency and low cost. SuperScript IV reverse transcriptase was found to be able to catalyze the RCRT reaction on the circular RNA template, and the reaction efficiency was enhanced by adding the nicking enzyme, Nb.BbvCI to the RCRT system. E. Coli RNA polymerase, instead of the commonly used T7 RNA polymerase, was applied to synthesize long-strand RNA product for its high universality and processivity. Under the optimized conditions, small RNAs can be precisely amplified by 105∼6 folds. The fidelity of the established method was demonstrated by the accordance of the sequencing result and the initial RNA sequences. Free from expensive thermal cycler (necessary for RT-PCR-based amplification), precise replication of the initial RNA and high fidelity will enable the established strategy to be applied in RNA-seq, mRNA profiling, microarray analysis and RNA-based SELEX as well.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Técnicas de Amplificação de Ácido Nucleico/métodos , RNA/metabolismo , Transcrição Reversa , DNA Circular/metabolismo , Escherichia coli/enzimologia , Proteínas de Escherichia coli/metabolismo
15.
Nucleic Acids Res ; 47(13): 6618-6631, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31173143

RESUMO

Riboswitches can regulate gene expression by direct and specific interactions with ligands and have recently attracted interest as potential drug targets for antibacterial. In this work, molecular dynamics (MD) simulations, free energy perturbation (FEP) and molecular mechanics generalized Born surface area (MM-GBSA) methods were integrated to probe the effect of mutations on the binding of ligands to guanine riboswitch (GR). The results not only show that binding free energies predicted by FEP and MM-GBSA obtain an excellent correlation, but also indicate that mutations involved in the current study can strengthen the binding affinity of ligands GR. Residue-based free energy decomposition was applied to compute ligand-nucleotide interactions and the results suggest that mutations highly affect interactions of ligands with key nucleotides U22, U51 and C74. Dynamics analyses based on MD trajectories indicate that mutations not only regulate the structural flexibility but also change the internal motion modes of GR, especially for the structures J12, J23 and J31, which implies that the aptamer domain activity of GR is extremely plastic and thus readily tunable by nucleotide mutations. This study is expected to provide useful molecular basis and dynamics information for the understanding of the function of GR and possibility as potential drug targets for antibacterial.

16.
Comput Intell Neurosci ; 2019: 8068357, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31214255

RESUMO

Background: Due to the redundant information contained in multichannel electroencephalogram (EEG) signals, the classification accuracy of brain-computer interface (BCI) systems may deteriorate to a large extent. Channel selection methods can help to remove task-independent electroencephalogram (EEG) signals and hence improve the performance of BCI systems. However, in different frequency bands, brain areas associated with motor imagery are not exactly the same, which will result in the inability of traditional channel selection methods to extract effective EEG features. New Method: To address the above problem, this paper proposes a novel method based on common spatial pattern- (CSP-) rank channel selection for multifrequency band EEG (CSP-R-MF). It combines the multiband signal decomposition filtering and the CSP-rank channel selection methods to select significant channels, and then linear discriminant analysis (LDA) was used to calculate the classification accuracy. Results: The results showed that our proposed CSP-R-MF method could significantly improve the average classification accuracy compared with the CSP-rank channel selection method.

17.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(4): 495-497, 2019 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-31109429

RESUMO

OBJECTIVE: Severe trauma or massive deep burn can cause significant immunosuppression associated with sepsis and multiple organ failure. Dendritic cell (DC), as the professional antigen presenting cells and activating factor of immune response, plays an extraordinary role in initiating and regulating congenital and adaptive immune response. The quantity, functional changes, relevant molecular mechanisms and reverse measures of DC after trauma/burn were reviewed in order to intensively study the changes of DC after trauma/burn and provide a reference for exploring effective intervention measures for trauma/burn.


Assuntos
Queimaduras/complicações , Células Dendríticas/patologia , Imunidade Adaptativa , Humanos , Insuficiência de Múltiplos Órgãos , Sepse , Índices de Gravidade do Trauma
18.
Hum Immunol ; 80(10): 848-854, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30965079

RESUMO

Preeclampsia (PE) is one of the major causes of maternal and perinatal mortality worldwide. This study aimed to determine the immunological characteristics of PE patients and normal pregnancy at the T cell receptor beta-chain (TRB) level by using high-throughput sequencing. High-throughput sequencing was performed to analyze the expression of TRB-CDR3 in circulating T cells. T cells were isolated from 36 healthy pregnant women, 24 patients with severe PE, and 18 patients with moderate PE. Rearranged mRNA sequences were assigned to their germline V, D, and J counterparts, and translated into proper amino acids by the IMGT database. In general, PE samples had more TRB-CDR3 reads and types than those of normal pregnant woman in the circulation, but the mean number of TRB-CDR3 reads and unique TRB-CDR3 reads in severe group was lower than that in the moderate group. In PE patients, the V7_9 and V20_1 gene loci were more prevalent than in healthy pregnant women. In addition, 4 kinds of TRB-CDR3 peptides were found to be highly relevant to the pathogenesis of PE. Of them, peptides matched to herpes simplex virus antigen-specific T cells were much lower in PE samples.

19.
Anal Chim Acta ; 1052: 153-162, 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30685034

RESUMO

Cell-SELEX is a powerful tool to screen aptamers binding to living cellular organisms such as bacteria, fungi and even oncocytes. Here, we developed an advanced cell-SELEX strategy featuring functionalized graphene oxide (GO) and isothermal rolling circle amplification (RCA) to select aptamers against a prevailing foodborne pathogen, Vibrio parahaemolyticus. Polyethyleneglycol (PEG) and chitosan (CTS) were grafted onto the sheet-like GO molecules to synthesize a PC-GO material. TEM and FT-IR characterization demonstrated that the PC-GO composites were near-nanometric scale and tethered with PEG and CTS moieties, a property that significantly improved its solubility in biological buffer solutions used in cell-SELEX process. PC-GO could bind with ssDNAs with lower affinities to target cells, therefore the selection efficiency is greatly enhanced. The cell-binding aptamer candidates (CACs) were amplified by 107 fold using complementary ring mediated (CRM-RCA), a created amplification method that generate single-stranded products, which could be directly used in the next round selection. As fueled by PC-GO and CRM-RCA, four highly specific aptamers with lowest Kd value of 10.3 ±â€¯2.5 nM were obtained. Flow cytometry analysis showed that all the four aptamers exhibited more than 75% binding affinity to V. parahaemolyticus than to other foodborne bacteria (less than 18%). Simple procedure, high efficiency, and free from expensive thermal cycler (required by PCR amplification) will enable the established strategy to find its applications in aptamer selecting against fungi, stem and cancerous cells as well.


Assuntos
Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/metabolismo , Grafite/química , Técnicas de Amplificação de Ácido Nucleico/métodos , Óxidos/química , Técnica de Seleção de Aptâmeros , Vibrio parahaemolyticus/metabolismo , Aptâmeros de Nucleotídeos/química , Modelos Moleculares , Conformação de Ácido Nucleico
20.
Circulation ; 139(12): 1472-1482, 2019 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-30667276

RESUMO

BACKGROUND: Lipoprotein(a) [Lp(a)] levels predict the risk of myocardial infarction (MI) in populations of European ancestry; however, few data are available for other ethnic groups. Furthermore, differences in isoform size distribution and the associated Lp(a) concentrations have not fully been characterized between ethnic groups. METHODS: We studied 6086 cases of first MI and 6857 controls from the INTERHEART study that were stratified by ethnicity and adjusted for age and sex. A total of 775 Africans, 4443 Chinese, 1352 Arabs, 1856 Europeans, 1469 Latin Americans, 1829 South Asians, and 1221 Southeast Asians were included in the study. Lp(a) concentration was measured in each participant using an assay that was insensitive to isoform size, with isoform size being assessed by Western blot in a subset of 4219 participants. RESULTS: Variations in Lp(a) concentrations and isoform size distributions were observed between populations, with Africans having the highest Lp(a) concentration (median=27.2 mg/dL) and smallest isoform size (median=24 kringle IV repeats). Chinese samples had the lowest concentration (median=7.8 mg/dL) and largest isoform sizes (median=28). Overall, high Lp(a) concentrations (>50 mg/dL) were associated with an increased risk of MI (odds ratio, 1.48; 95% CI, 1.32-1.67; P<0.001). The association was independent of established MI risk factors, including diabetes mellitus, smoking, high blood pressure, and apolipoprotein B and A ratio. An inverse association was observed between isoform size and Lp(a) concentration, which was consistent across ethnic groups. Larger isoforms tended to be associated with a lower risk of MI, but this relationship was not present after adjustment for concentration. Consistent with variations in Lp(a) concentration across populations, the population-attributable risk of high Lp(a) for MI varied from 0% in Africans to 9.5% in South Asians. CONCLUSIONS: Lp(a) concentration and isoform size varied markedly between ethnic groups. Higher Lp(a) concentrations were associated with an increased risk of MI and carried an especially high population burden in South Asians and Latin Americans. Isoform size was inversely associated with Lp(a) concentration, but did not significantly contribute to risk.

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