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1.
Sci Rep ; 14(1): 5298, 2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438448

RESUMO

To investigate the short-term effects and differences between exercise alone and exercise combined with self-mobilization training on chronic non-specific neck pain (CNSNP). Thirty subjects who met the criteria were recruited and randomly assigned to the exercise training group, the exercise combined with cervical self-mobilization training group (ECCM), and the exercise combined with cervicothoracic self-mobilization training group (ECCTM). The exercise training group received 6 weeks of deep neck flexor under biofeedback and scapular stability training, and the other two groups received 6 weeks of cervical self-mobilization and cervicothoracic self-mobilization, respectively, in addition to exercise training. Neck pain, cervical range of motion (ROM), neck disability, strength and endurance of deep neck flexor and quality of life were assessed before and after 6 weeks of training. The study results showed that all the three training programs for 6 weeks increased the strength and endurance of deep neck flexor, increased cervical ROM, reduced pain, and improved neck function (P < 0.05). The exercise combined with self-mobilization two groups compared with only the exercise training group had better improvement in ROM of extension, lateral flexion, rotation and quality of life (P < 0.05). Compared with exercise alone and exercise combined with cervical self-mobilization training, the exercise combined with cervicothoracic self-mobilization training was the best in improving ROM of right lateral flexion (exercise training group vs ECCTM: P < 0.01, d = 1.61, ECCM vs ECCTM: P < 0.05, d = 1.14) and pain (exercise training group vs ECCTM: P < 0.05, d = 1.34, ECCM vs ECCTM: P < 0.05, d = 1.23). Deep flexor muscle and shoulder stability training can improve the endurance and strength of the deep flexor muscles of the neck and coordinate the movement patterns of the shoulder and neck. Self-mobilization techniques can promote improvements in cervical lateral flexion and rotation range of motion, alleviate neck disability and further improve quality of life. A combination of exercise and cervicothoracic self-mobilization training appears beneficial for the management of neck pain.


Assuntos
Manipulação da Coluna , Cervicalgia , Humanos , Exercício Físico , Terapia por Exercício , Cervicalgia/terapia , Qualidade de Vida
2.
J Athl Train ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38419428

RESUMO

CONTEXT: Researchers have shown that patients with chronic ankle instability (CAI) have deficits in memory and attention allocation. This functional deficit affects the lower extremity performance. Motor-cognitive dual-task training may improve lower limb dysfunction caused by central nervous system injury. Whether dual-task training is more favorable than single-task training for neuromuscular control in patients with single-task training still needs to be further proven. OBJECTIVE: To determine whether balance-cognitive dual-task training can influence cortical activity and has more effective treatment effects than balance single-task training. DESIGN: Randomized controlled clinical trial (Clinical Trials: XXX). SETTING: Rehabilitation training room. PATIENTS OR OTHER PARTICIPANTS: After recruitment, twenty-four patients with CAI (age=22.33±2.43 years, height=175.62±7.7 cm, mass=70.63±14.59 kg) were block randomized into two groups. INTERVENTION(S): Protocols were performed three times per week for six weeks. The single-task group underwent one-leg static balance training with and without vision and hopping balance training. The dual-task group underwent balance and cognitive training (backward counting task). MAIN OUTCOME MEASURE(S): The follow variables were assessed before and after the interventions: cortical activity, proprioception, muscle onset time, and dynamic balance. We performed MANOVAs to compare changes of main effects and interactions across groups and time. A post-hoc Bonferroni test was performed for pairwise comparisons when there were significant interactions with the MANOVAs. RESULTS: Twenty-four participants successfully completed the six-week interventions. Proprioception, peroneus longus muscle onset time, and dynamic postural control improved significantly after the interventions in both groups (P<0.05). Dual-task training was superior to single-task training in improving JPS plantarflexion, shortening peroneus longus muscle onset time, and altering cortical activity(P<0.05). CONCLUSIONS: A six-week balance training program or balance combined with cognitive training could improve the functional deficits associated with CAI. Meanwhile, the dual-task training could improve cortical activity and lower extremity function.

3.
Nature ; 619(7971): 837-843, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37380774

RESUMO

The human gut microbiome constantly converts natural products derived from the host and diet into numerous bioactive metabolites1-3. Dietary fats are essential micronutrients that undergo lipolysis to release free fatty acids (FAs) for absorption in the small intestine4. Gut commensal bacteria modify some unsaturated FAs-for example, linoleic acid (LA)-into various intestinal FA isomers that regulate host metabolism and have anticarcinogenic properties5. However, little is known about how this diet-microorganism FA isomerization network affects the mucosal immune system of the host. Here we report that both dietary factors and microbial factors influence the level of gut LA isomers (conjugated LAs (CLAs)) and that CLAs in turn modulate a distinct population of CD4+ intraepithelial lymphocytes (IELs) that express CD8αα in the small intestine. Genetic abolition of FA isomerization pathways in individual gut symbionts significantly decreases the number of CD4+CD8αα+ IELs in gnotobiotic mice. Restoration of CLAs increases CD4+CD8αα+ IEL levels in the presence of the transcription factor hepatocyte nuclear factor 4γ (HNF4γ). Mechanistically, HNF4γ facilitates CD4+CD8αα+ IEL development by modulating interleukin-18 signalling. In mice, specific deletion of HNF4γ in T cells leads to early mortality from infection by intestinal pathogens. Our data reveal a new role for bacterial FA metabolic pathways in the control of host intraepithelial immunological homeostasis by modulating the relative number of CD4+ T cells that were CD4+CD8αα+.


Assuntos
Ácidos Graxos , Microbioma Gastrointestinal , Linfócitos Intraepiteliais , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Linfócitos Intraepiteliais/imunologia , Linfócitos Intraepiteliais/metabolismo , Isomerismo , Camundongos Endogâmicos C57BL , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Lipólise , Ácido Linoleico/metabolismo , Imunidade nas Mucosas
4.
J Org Chem ; 87(21): 14536-14543, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36269896

RESUMO

We report a cathodic reduction-dominated electrochemical approach for the hydrogenation of azobenzenes in dichloromethane. With cheap and readily available N,N-diisopropylethylamine as a catalytic mediator, the reaction proceeded smoothly in a simple undivided cell under constant-current electrolysis. A series of azobenzenes were successfully reduced to the corresponding hydrazobenzenes in moderate to high yields at room temperature. Preliminarily mechanistic studies indicate that solvent dichloromethane acts as a hydrogen source. The use of a common solvent as a hydrogen source, no need for stoichiometric mediators or metallic reductants, and mild conditions make this work a more straightforward and sustainable protocol for hydrogenation of azobenzenes.

5.
Int J Endocrinol ; 2022: 4995196, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35879975

RESUMO

Background: Parathyroid tumors are common endocrine neoplasias associated with primary hyperparathyroidism. Although numerous studies have studied the subject, the predictive value of gene biomarkers nevertheless remains low. Methods: In this study, we performed genomic analysis of abnormal DNA methylation in parathyroid tumors. After data preprocessing, differentially methylated genes were extracted from patients with parathyroid tumors by using t-tests. Results: After refinement of the basic differential methylation, 28241 unique CpGs (634 genes) were identified to be methylated. The methylated genes were primarily involved in 7 GO terms, and the top 3 terms were associated with cyst morphogenesis, ion transport, and GTPase signal. Following pathway enrichment analyses, a total of 10 significant pathways were enriched; notably, the top 3 pathways were cholinergic synapses, glutamatergic synapses, and oxytocin signaling pathways. Based on PPIN and ego-net analysis, 67 ego genes were found which could completely separate the diseased group from the normal group. The 10 most prominent genes included POLA1, FAM155 B, AMMECR1, THOC2, CCND1, CLDN11, IDS, TST, RBPJ, and GNA11. SVM analysis confirmed that this grouping approach was precise. Conclusions: This research provides useful data to further explore novel genes and pathways as therapeutic targets for parathyroid tumors.

6.
MycoKeys ; 88: 109-121, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35585933

RESUMO

Three new species, Candolleomycesincanus, C.subcandolleanus and C.yanshanensis, were found and described from Yanshan Mountains in China. The identification is based on morphological observation combined with phylogenetic analysis of ITS-LSU-Tef1α-TUB2. This study enriched the species diversity of Candolleomyces in Yanshan Mountains and provided important data support for the systematic study of Candolleomyces in the future.

7.
ACS Appl Mater Interfaces ; 14(8): 10047-10054, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35133815

RESUMO

Metallic aerogels (MAs), imparting the active catalytic properties of nanostructured noble metals to macroscopic aerogels, draw tremendous interest in diverse fields owing to the unique features of three-dimensional interconnected channels, self-supported architectures, and pure metallic backbones. Moreover, flexible manipulation of compositions, high electrical conductivity, and abundant active sites of MAs contribute to the great potential to mimic natural enzymes. However, the cumbersome synthetic process takes a couple of hours to days, and unavoidable impurities usually impede surface electrons/mass transfer, posing the decrease of stability and enzyme-like activity of MAs. Here, a PdIr bimetallic aerogel prepared in the ethanol phase via spontaneous assembly and a surfactant-free strategy is reported. Gelation kinetics of PdIr aerogels in ethanol is increased with 2-4 orders of magnitude compared to the traditional preparation method in water. Owing to the intrinsic physicochemical properties, PdIr aerogels exhibit the high activity of peroxidase mimics using 3,3',5,5'-tetramethylbenzidine as a chromogenic probe. In addition, the PdIr aerogels maintain relatively high activity at an elevated temperature and pH of 3-7, demonstrating their good stability and survivability. Utilizing the exceptional peroxidase-like activity of PdIr aerogels, we realized the quantitative bioassay for H2O2 and total antioxidant capacity, indicating enormous potential in the quality evaluation of real samples.


Assuntos
Colorimetria , Peroxidase , Antioxidantes/farmacologia , Bioensaio , Colorimetria/métodos , Peróxido de Hidrogênio/química
8.
Nature ; 577(7791): 543-548, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31915378

RESUMO

Although maternal antibodies protect newborn babies from infection1,2, little is known about how protective antibodies are induced without prior pathogen exposure. Here we show that neonatal mice that lack the capacity to produce IgG are protected from infection with the enteric pathogen enterotoxigenic Escherichia coli by maternal natural IgG antibodies against the maternal microbiota when antibodies are delivered either across the placenta or through breast milk. By challenging pups that were fostered by either maternal antibody-sufficient or antibody-deficient dams, we found that IgG derived from breast milk was crucial for protection against mucosal disease induced by enterotoxigenic E. coli. IgG also provides protection against systemic infection by E. coli. Pups used the neonatal Fc receptor to transfer IgG from milk into serum. The maternal commensal microbiota can induce antibodies that recognize antigens expressed by enterotoxigenic E. coli and other Enterobacteriaceae species. Induction of maternal antibodies against a commensal Pantoea species confers protection against enterotoxigenic E. coli in pups. This role of the microbiota in eliciting protective antibodies to a specific neonatal pathogen represents an important host defence mechanism against infection in neonates.


Assuntos
Anticorpos/imunologia , Escherichia coli Enterotoxigênica/imunologia , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/prevenção & controle , Imunidade Materno-Adquirida/imunologia , Recém-Nascido/imunologia , Microbiota/imunologia , Leite Humano/imunologia , Animais , Anticorpos/sangue , Anticorpos/metabolismo , Aleitamento Materno , Reações Cruzadas/imunologia , Infecções por Escherichia coli/microbiologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Masculino , Camundongos , Mães , Pantoea/imunologia , Receptores Fc/imunologia , Receptores Fc/metabolismo , Simbiose/imunologia
9.
China CDC Wkly ; 2(39): 757-760, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34594755

RESUMO

WHAT IS ALREADY KNOWN ON THIS TOPIC?: Human brucellosis, a neglected zoonotic disease, causes more than 500,000 new cases each year globally. The disease is of major public health concern in China, and northern provinces are traditionally endemic areas. WHAT IS ADDED BY THIS REPORT?: This is the first published outbreak of occupational brucellosis involving multiple clusters in Hubei Province. This investigation characterizes the transmission chain of the outbreak and reveals that provinces south of the Yangtze River are faced with a series of challenges and hurdles to overcome including, but not limited to, health education, law enforcement, and occupational protection. WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE?: In addition to measures aimed at this outbreak, the local agricultural department has issued special notices based on this investigation to adjust and strengthen local eradication program of brucellosis.

10.
Nature ; 577(7790): 410-415, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31875848

RESUMO

The metabolic pathways encoded by the human gut microbiome constantly interact with host gene products through numerous bioactive molecules1. Primary bile acids (BAs) are synthesized within hepatocytes and released into the duodenum to facilitate absorption of lipids or fat-soluble vitamins2. Some BAs (approximately 5%) escape into the colon, where gut commensal bacteria convert them into various intestinal BAs2 that are important hormones that regulate host cholesterol metabolism and energy balance via several nuclear receptors and/or G-protein-coupled receptors3,4. These receptors have pivotal roles in shaping host innate immune responses1,5. However, the effect of this host-microorganism biliary network on the adaptive immune system remains poorly characterized. Here we report that both dietary and microbial factors influence the composition of the gut BA pool and modulate an important population of colonic FOXP3+ regulatory T (Treg) cells expressing the transcription factor RORγ. Genetic abolition of BA metabolic pathways in individual gut symbionts significantly decreases this Treg cell population. Restoration of the intestinal BA pool increases colonic RORγ+ Treg cell counts and ameliorates host susceptibility to inflammatory colitis via BA nuclear receptors. Thus, a pan-genomic biliary network interaction between hosts and their bacterial symbionts can control host immunological homeostasis via the resulting metabolites.


Assuntos
Ácidos e Sais Biliares/metabolismo , Microbioma Gastrointestinal , Homeostase , Intestinos/imunologia , Intestinos/microbiologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Linfócitos T Reguladores/imunologia , Animais , Ácidos e Sais Biliares/química , Camundongos Endogâmicos C57BL , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética
11.
Proc Natl Acad Sci U S A ; 116(1): 193-198, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30510007

RESUMO

Glycoconjugate vaccines are among the most effective interventions for preventing several serious infectious diseases. Covalent linkage of the bacterial capsular polysaccharide to a carrier protein provides CD4+ T cells with epitopes that facilitate a memory response to the polysaccharide. Classically, the mechanism responsible for antigen processing was thought to be similar to what was known for hapten-carrier conjugates: protease digestion of the carrier protein in the endosome and presentation of a resulting peptide to the T cell receptor on classical peptide-recognizing CD4+ T cells. Recently, an alternative mechanism has been shown to be responsible for the memory response to some glycoconjugates. Processing of both the protein and the polysaccharide creates glycopeptides in the endosome of antigen-presenting cells. For presentation, the peptide portion of the glycopeptide is bound to MHCII, allowing the covalently linked glycan to activate carbohydrate-specific helper CD4+ T cells (Tcarbs). Herein, we assessed whether this same mechanism applies to conjugates prepared from other capsular polysaccharides. All of the glycoconjugates tested induced Tcarb-dependent responses except that made with group C Neisseria meningitidis; in the latter case, only peptides generated from the carrier protein were critical for helper T cell recognition. Digestion of this acid-sensitive polysaccharide, a linear homopolymer of α(2 → 9)-linked sialic acid, to the size of the monomeric unit resulted in a dominant CD4+ T cell response to peptides in the context of MHCII. Our results show that different mechanisms of presentation, based on the structure of the carbohydrate, are operative in response to different glycoconjugate vaccines.


Assuntos
Imunidade Adaptativa/imunologia , Glicoconjugados/imunologia , Polissacarídeos Bacterianos/imunologia , Vacinas Conjugadas/imunologia , Imunidade Adaptativa/efeitos dos fármacos , Animais , Formação de Anticorpos/imunologia , Antígenos/imunologia , Epitopos/imunologia , Feminino , Citometria de Fluxo , Glicoconjugados/farmacologia , Vacinas Meningocócicas/imunologia , Vacinas Meningocócicas/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Ácido N-Acetilneuramínico , Neisseria meningitidis/imunologia , Polissacarídeos Bacterianos/farmacologia , Linfócitos T Auxiliares-Indutores/imunologia , Vacinas Conjugadas/farmacologia
12.
ACS Appl Mater Interfaces ; 9(37): 32089-32096, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28849916

RESUMO

In this work, a novel fluorescent transformation phenomenon of oligonucleotide-encapsulated silver nanoclusters (AgNCs) was demonstrated, in which green-emissive AgNCs effectively transformed to red-emissive AgNCs when placed in close proximity to a special DNA fragment (denoted as convertor here). Taking advantage of a catalyzed-hairpin-assembly (CHA) amplification strategy, we rationally and compatibly engineered a simple and sensitive AgNC-based fluorescent signal amplification strategy through the ratiometric catalyzed-assembly (RCA) of green-emissive NanoCluster Beacon (NCB) with a convertor modified DNA hairpin to induce the template transformation circularly. The proposed ratiometric fluorescent biosensing platform based on RCA-amplified NCB (RCA-NCB) emits intense green fluorescence in the absence of target DNA and will undergo consecutively fluorescent signal transformation from green emission to red emission upon exposure to its target DNA. The ratiometric adaptation of the NCB to CHA circuit advances their general usability as biosensing platform with great improvements in detection sensitivity. By measuring the fluorescence intensity ratio of the red emission and green emission, the proposed RCA-NCB platform exhibits sensitive and accurate analytical performance toward Werner Syndrome-relevant gene, the proof-of-concept target in this work. A low detection limit down to the pM level was achieved, which is lower than most of the reported AgNC-based fluorescent DNA biosensors, making the proposed RCA-NCB biosensing strategy appealing in amplifying the ratiometric fluorescent signal for sensitive DNA detection. Moreover, our proposed RCA-NCB platform shows good recovery toward the target DNA in real human serum samples, illustrating their potential promise for clinical and imaging applications in the future.


Assuntos
Nanoestruturas , Técnicas Biossensoriais , Catálise , DNA , Humanos , Limite de Detecção , Prata , Espectrometria de Fluorescência
13.
ACS Appl Mater Interfaces ; 9(15): 13102-13110, 2017 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-28367619

RESUMO

Although researches until now have emphasized the influence of an oligonucleotide sequence on the fluorescence of oligonucleotide-stabilized silver nanoclusters (AgNCs), this influence has been explored as a novel ratiometric fluorescent signal transduction in this work. This study builds on our original discovery of a template-transformation phenomenon, which demonstrated that the connection of a special DNA fragment (5'-CACCGCTTT-3') with a green-emitting AgNC nucleation sequence (GNuS, 5'-TGCCTTTTGGGGACGGATA-3') creates a red-emitting AgNC nucleation sequence (RNuS, 5'-CACCGCTTTTGCCTTTTGGGGACGGATA-3'). Attempts to expand this idea and construct elegant ratiometric NanoCluster Beacons (NCBs) for DNA sequence detection are not straightforward, and, thus, we carried out a series of investigations with the goal of understanding the mechanism of this template-transformation phenomenon. Experimental results showed that the six-nucleotide fragment (5'-CACCGC-3') at the 5'-end of RNuS acts as a template convertor and takes full responsibility for the template transformation from GNuS to RNuS. Moreover, we found that the appropriate proximity of the convertor to GNuS also plays a significant role in the template transformation. We then show that the insights gained here for the template-transformation mechanism allow us to construct ratiometric NCBs by simply appending the convertor and the GNuS onto a rationally designed stem-loop probe. This new type of NCB emits intense red fluorescence without the addition of a target DNA and emerges as a new, bright green emission only when hybridized to its target DNA. By measuring the distinct variation in the fluorescence intensity ratios of green and red emission, this ratiometric NCB was demonstrated to sensitively detect Hepatitis-A virus gene sequences, a proof-of-concept target in this work, with good selectivity.


Assuntos
DNA/química , Corantes , Nanopartículas Metálicas , Nanoestruturas , Prata , Espectrometria de Fluorescência
14.
Gene ; 613: 25-29, 2017 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-28249772

RESUMO

BACKGROUND AND PURPOSE: Osteoprotegerin (OPG) is a member of the tumor necrosis factor receptor superfamily and is involved in the progress of atherosclerosis. We chose a gene polymorphism locus, OPG rs3102735, to explore how OPG gene polymorphisms relate to the occurrence of ischemic stroke and microembolic signals and to evaluate their relationship with the severity of neurologic deficits at admission and the degree of vascular stenosis. METHODS: We studied 251 patients diagnosed with large artery atherosclerosis (LAA) stroke and 121 controls. The LAA stroke patients were divided into clinical subgroups according to the presence of microembolic signals, severity of neurologic deficits at admission, and the degree of vascular stenosis. The OPG rs3102735 gene polymorphism was examined by polymerase chain reaction and restriction fragment length polymorphism. The microembolic signals (MES) were monitored by transcranial Doppler (TCD) for 60min within 72h of stroke onset. The severity of neurologic deficits at admission was evaluated by the National Institutes of Health Stroke Scale (NIHSS). RESULTS: The CC+CT genotypes and allele C frequencies of the rs3102735 gene polymorphism were significantly higher in the LAA group than in the control group (39% vs. 25.6%, P=0.026; 21.7% vs.13.2%, P=0.006), higher in MES-positive compared to MES-negative patients (58.7% vs. 32.4%, P<0.01; 34.1% vs.17.6%, P<0.01), and higher in patients with an NIHSS Score (≥6) than in those with an NIHSS Score (<6) (46.9% vs.33.3%, P=0.031; 43.4% vs.18.3%, P=0.04). However, the genotypes and allele frequencies of SNPs in rs3102735 did not show significant differences in the degree of vascular stenosis (P>0.05). CONCLUSION: Our findings suggest that the OPG rs3102735 gene polymorphism might be related to the occurrence of LAA ischemic stroke, microembolic signals and stroke severity and not the degree of vascular stenosis.


Assuntos
Isquemia Encefálica/genética , Osteoprotegerina/genética , Polimorfismo de Nucleotídeo Único , Acidente Vascular Cerebral/genética , Doença Aguda , Idoso , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Estenose das Carótidas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/fisiopatologia
15.
Anal Chem ; 88(19): 9691-9698, 2016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27582358

RESUMO

Herein, a novel universal and label-free homogeneous electrochemical platform is demonstrated, on which a complete set of DNA-based two-input Boolean logic gates (OR, NAND, AND, NOR, INHIBIT, IMPLICATION, XOR, and XNOR) is constructed by simply and rationally deploying the designed DNA polymerization/nicking machines without complicated sequence modulation. Single-stranded DNA is employed as the proof-of-concept target/input to initiate or prevent the DNA polymerization/nicking cyclic reactions on these DNA machines to synthesize numerous intact G-quadruplex sequences or binary G-quadruplex subunits as the output. The generated output strands then self-assemble into G-quadruplexes that render remarkable decrease to the diffusion current response of methylene blue and, thus, provide the amplified homogeneous electrochemical readout signal not only for the logic gate operations but also for the ultrasensitive detection of the target/input. This system represents the first example of homogeneous electrochemical logic operation. Importantly, the proposed homogeneous electrochemical logic gates possess the input/output homogeneity and share a constant output threshold value. Moreover, the modular design of DNA polymerization/nicking machines enables the adaptation of these homogeneous electrochemical logic gates to various input and output sequences. The results of this study demonstrate the versatility and universality of the label-free homogeneous electrochemical platform in the design of biomolecular logic gates and provide a potential platform for the further development of large-scale DNA-based biocomputing circuits and advanced biosensors for multiple molecular targets.


Assuntos
Técnicas Biossensoriais , Computadores Moleculares , DNA de Cadeia Simples/química , Técnicas Eletroquímicas , Lógica , DNA de Cadeia Simples/síntese química , Quadruplex G
16.
Anal Chem ; 88(4): 2212-9, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26813733

RESUMO

As is well-known, graphene shows a remarkable difference in affinity toward nonstructured single-stranded (ss) DNA and double-stranded (ds) DNA. This property makes it popular to prepare DNA-based optical sensors. In this work, taking this unique property of graphene in combination with the sensitive electrochemical transducer, we report a novel affinity-mediated homogeneous electrochemical aptasensor using graphene modified glassy carbon electrode (GCE) as the sensing platform. In this approach, the specific aptamer-target recognition is converted into an ultrasensitive electrochemical signal output with the aid of a novel T7 exonuclease (T7Exo)-assisted target-analog recycling amplification strategy, in which the ingeniously designed methylene blue (MB)-labeled hairpin DNA reporters are digested in the presence of target and, then, converted to numerous MB-labeled long ssDNAs. The distinct difference in differential pulse voltammetry response between the designed hairpin reporters and the generated long ssDNAs on the graphene/GCE allows ultrasensitive detection of target biomolecules. Herein, the design and working principle of this homogeneous electrochemical aptasensor were elucidated, and the working conditions were optimized. The gel electrophoresis results further demonstrate that the designed T7Exo-assisted target-analog recycling amplification strategy can work well. This electrochemical aptasensor realizes the detection of biomolecule in a homogeneous solution without immobilization of any bioprobe on electrode surface. Moreover, this versatile homogeneous electrochemical sensing system was used for the determination of biomolecules in real serum samples with satisfying results.


Assuntos
Aptâmeros de Nucleotídeos/química , DNA de Cadeia Simples/análise , Técnicas Eletroquímicas , Exodesoxirribonucleases/metabolismo , Grafite/química , Técnicas de Amplificação de Ácido Nucleico , Aptâmeros de Nucleotídeos/análise , DNA de Cadeia Simples/química , Técnicas Eletroquímicas/instrumentação , Eletrodos
17.
ACS Appl Mater Interfaces ; 7(51): 28566-75, 2015 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-26652835

RESUMO

In this contribution, taking the discrimination ability of graphene over single-stranded (ss) DNA/double-stranded (ds) DNA in combination with the electrochemical impedance transducer, we developed a novel label-free homogeneous electrochemical biosensor using graphene-modified glassy carbon electrode (GCE) as the sensing platform. To convert the specific aptamer-target recognition into ultrasensitive electrochemical signal output, a novel aptamer-switched bidirectional DNA polymerization (BDP) strategy, capable of both target recycling and exponential signal amplification, was compatibly developed in this study. In this strategy, all the designed DNA structures could be adsorbed on the graphene/GCE and, thus, serve as the electrochemical impedance signal reporter, while the target acts as a trigger of this BDP reaction, in which these designed DNA structures are bound together and, then, converted to long dsDNA duplex. The distinct difference in electrochemical impedance spectroscopy between the designed structures and generated long dsDNA duplex on the graphene/GCE allows label-free and homogeneous detection of target down to femto-gram level. The target can be displaced from aptamer through the polymerization to initiate the next recognition-polymerization cycle. Herein, the design and signaling principle of aptamer-switched BDP amplification system were elucidated, and the working conditions were optimized. This method not only provides a universal platform for electrochemical biosensing but also shows great potential in biological process researches and clinic diagnostics.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , DNA/química , Técnicas Eletroquímicas/métodos , Grafite/química , Aptâmeros de Nucleotídeos/genética , Técnicas Biossensoriais/instrumentação , DNA/genética , Técnicas Eletroquímicas/instrumentação , Polimerização
18.
Zhonghua Gan Zang Bing Za Zhi ; 18(7): 502-5, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-20678439

RESUMO

OBJECTIVES: To evaluate the efficacy of recombinant human adenovirus p53 gene therapy (rAd-p53) in the rabbit VX2 liver cancer model using different interventional therapy approach. METHODS: Thirty New Zealand rabbits implanted with VX2 tumor in the liver were randomized into five groups with six of each. The tumor volumes (V1) were measured by MRI and CT scan 11 days after tumors implanted. The interventional therapy scheme performed as below: intraarterial 0.9% saline solution perfusion in group A, transcatheter arterial embolization with 0.5 ml ultrafluid lipiodol in group B, intraarterial rAd-p53 gene perfusion in group C (1 x 10(6)/VP); intraarterial rAd-p53 gene perfusion (1 x 10(6)/VP) in combination with transcatheter arterial embolization (ultrofluid lipiodol, 0.5 ml) in group D and intratumoral rAd-p53 gene (1 x 10(6)/VP) injection in group E. The tumor volumes (V2) were measured by MRI and CT scan, and the tumor growth ratios were calculated 14 days after interventional procedures. Then all animals were sacrificed. RESULTS: The tumor tissues were explanted for immunohistochemistry to observe the expressions of vascular endothelial cell growth factor (VEGF) and factor VIII. Microvessel density (MVD) of the tumor tissues was assessed by factor VIII immunohistochemical analysis. In addition, apoptotic index was assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. The tumor volumes before therapy were (79.4+/-8.2), (75.3+/-7.8), (74.6+/-6.6), (78.7+/-9.1), (75.8+/-8.4) mm(3) respectively, without differences found among them (F = 12.248, P = 0.0636). But the tumor volumes after therapy were (564.7+/-96.7), (176.5+/-83.2), (239.6+/-42.8), (159.8+/-58.6), (334.7+/-32.6) mm(3) respectively (F = 24.537, P = 0.0218). The tumor growth ratios were 6.9, 2.6, 3.1, 1.6 and 4.1 respectively. The mean apoptosis index were 12.0%+/-1.1%, 14.5%+/-2.1%, 17.6%+/-2.3%, 18.6%+/-2.3% and 19.6%+/-2.5% respectively. with significant differences in group E in comparison with the other four groups. Mean positive ratio of VEGF was 50.0%, 83.3%, 83.3%, 50.0% and 50.0% respectively, with significant differences observed in group B and group C compared with the other three groups (F = 7.84, P = 0.019). The differences of VIII factor positive expression ratio among each group were significant (F = 0.854, P = 0.018). Statistical analysis showed a positive correlation between the expression of VEGF and MVD (r = 2.400, P = 0.0233). CONCLUSION: The rAd-p53 has effective treatment outcomes in VX2 rabbit liver cancer, and intra-arterial rAd-p53 gene perfusion in combination with transcatheter arterial embolization is the best approach in comparison with intra-arterial rAd-p53 gene perfusion, transcatheter arterial embolization and intratumoral rAd-p53 gene injection alone.


Assuntos
Adenovírus Humanos/genética , Genes p53 , Terapia Genética , Neoplasias Hepáticas Experimentais/terapia , Animais , Neoplasias Hepáticas Experimentais/patologia , Coelhos , Resultado do Tratamento
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