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1.
Anal Chem ; 93(41): 13928-13934, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34609848

RESUMO

Herein, a new field-free and highly ordered spherical nucleic acid (SNA) nanostructure was self-assembled directly by ferrocene (Fc)-labeled DNA tweezers and DNA linkers based on the Watson-Crick base pairing rule, which was employed as an electrochemiluminescence (ECL) quenching switch with improved recognition efficiency due to the high local concentration of the ordered nanostructure. Moreover, with a collaborative strategy combined with the advantages of both self-accelerated approach and pore confinement-enhanced ECL effect, the mesoporous silica nanospheres (mSiO2 NSs) were prepared to be filled with rubrene (Rub) as ECL emitters and Pt nanoparticles (PtNPs) as coreaction accelerators (Rub-Pt@mSiO2 NSs), which demonstrated high ECL response in the aqueous media (dissolved O2 as coreactant). When the SNA nanostructure was immobilized on the Rub-Pt@mSiO2 NSs-modified electrode, it presented a "signal off" state owing to the quenching effect of the Fc molecules. As a proof of concept, the SNA-based ECL switch platform was applied in the detection of microRNA let-7b (let-7b). Impressively, in the presence of the target let-7b, a deconstruction of the SNA nanostructure was actuated, causing the Fc to leave the electrode surface and achieved an extremely high ECL recovery ("signal on" state). Hence, a sensitive determination for let-7b was realized with a low detection limit of 1.8 aM ranging from 10 aM to 1 nM by employing the Rub-Pt@mSiO2 NSs-based ECL platform combined with the target-triggered SNA deconstruction, which also offered an ingenious method for the further applications of biomarker analyses.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , MicroRNAs , Ácidos Nucleicos , Técnicas Eletroquímicas , Limite de Detecção , Medições Luminescentes
2.
Anal Chem ; 92(16): 11044-11052, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32677426

RESUMO

Herein, an amphiphilic perylene derivative (denoted as PTC-DEDA) was explored as DNA intercalators endowed with an enhanced affinity and intense electrochemiluminescence (ECL) to construct a target-induced DNA hydrogel biosensing platform for the sensitive detection of microRNA let-7a (miRNA let-7a). Specifically, the DNA hydrogel with numerous dendritic DNA structures was in situ generated via a target-induced nonlinear hybrid chain reaction in the presence of miRNA let-7a, which possessed a large loading capacity to entrap massive DNA intercalators. Then, the PTC-DEDA with positive charges could easily intercalate into the DNA grooves due to the inherent amphipathic structure, achieving a strong ECL signal. Using the proposed PTC-DEDA as both DNA intercalators and ECL emitters, the DNA hydrogel biosensing platform exhibited a high stability and an excellent sensitivity for miRNA let-7a, with a desirable linear range (10 fM to 10 nM) and a low detection limit (1.49 fM). Significantly, the work provides a potential alternative to develop simple and high-efficiency ECL platforms for biochemical analysis applications.


Assuntos
Técnicas Biossensoriais/métodos , DNA/química , Hidrogéis/química , Substâncias Intercalantes/química , MicroRNAs/análise , Linhagem Celular Tumoral , Ouro/química , Humanos , Limite de Detecção , Substâncias Luminescentes/química , Nanopartículas de Magnetita/química , Paládio/química , Perileno/análogos & derivados , Sulfatos/química
3.
J Formos Med Assoc ; 119(5): 950-956, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31822372

RESUMO

BACKGROUND/PURPOSE: This study aimed to determine the potential effects of angiopoietin-2 (Ang-2), von Willebrand factor (vWF), and extravascular lung water index (EVLWI) on the risk of mortality in sepsis patients with concomitant acute respiratory distress syndrome (ARDS). METHODS: This retrospective study recruited 41 sepsis patients with concomitant ARDS from January 2015 to June 2018. Data of Ang-2 and vWF levels, EVLWI, and sequential organ failure assessment scores were collected at 0, 24, and 48 h after admission to the hospital. RESULTS: The length of intensive care unit stay (P = 0.041) and Acute Physiology and Chronic Health Evaluation-2 (APACHE II) score (P = 0.003) were associated with the risk of mortality. Furthermore, increased Ang-2 levels and EVLWI at 24 h and 48 h were associated with an increased risk of mortality. Moreover, the APACHE II score at hospital admission significantly predicted the risk of mortality (area under the curve [AUC], 0.834; 95% confidence interval [CI], 0.665-0.983). Finally, the models containing a combination of Ang-2 level and EVLWI at 24 h (AUC, 0.908; 95% CI, 0.774-0.996) and Ang-2 level and EVLWI at 48 h (AUC, 0.981; 95% CI, 0.817-1.000) had high diagnostic values for predicting risk of mortality. CONCLUSION: The study findings indicate that Ang-2 levels and EVLWI at 24 h and 48 h after admission are significantly associated with the risk of mortality.


Assuntos
Angiopoietina-2 , Água Extravascular Pulmonar , Síndrome do Desconforto Respiratório , Sepse , Fator de von Willebrand , Humanos , Prognóstico , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Sepse/mortalidade
4.
J Proteome Res ; 16(5): 1944-1961, 2017 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-28357858

RESUMO

Paper mulberry is a valuable woody species with a good chilling tolerance. In this study, phosphoproteomic analysis, physiological measurement, and mRNA quantification were employed to explore the molecular mechanism of chilling (4 °C) tolerance in paper mulberry. After chilling for 6 h, 427 significantly changed phosphoproteins were detected in paper mulberry seedlings without obvious physiological injury. When obvious physiological injury occurred after chilling for 48 h, a total of 611 phosphoproteins were found to be significantly changed at the phosphorylation level. Several protein kinases, especially CKII, were possibly responsible for these changes according to conserved sequence analysis. The results of Gene Ontology analysis showed that phosphoproteins were mainly responsible for signal transduction, protein modification, and translation during chilling. Additionally, transport and cellular component organization were enriched after chilling for 6 and 48 h, respectively. On the basis of the protein-protein interaction network analysis, a protein kinase and phosphatases hub protein (P1959) were found to be involved in cross-talk between Ca2+, BR, ABA, and ethylene-mediated signaling pathways. We also highlighted the phosphorylation of BpSIZ1 and BpICE1 possibly impacted on the CBF/DREB-responsive pathway. From these results, we developed a schematic for the chilling tolerance mechanism at phosphorylation level.


Assuntos
Adaptação Fisiológica , Temperatura Baixa , Morus/química , Fosfoproteínas/análise , Proteínas de Plantas/análise , Proteômica/métodos , Ontologia Genética , Fosforilação , Mapas de Interação de Proteínas , Processamento de Proteína Pós-Traducional , Transdução de Sinais
5.
J Clin Monit Comput ; 30(5): 569-75, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26298710

RESUMO

We know that a 10 cm departure from the reference level of pressure transducer position is equal to a 7.5 mmHg change of invasive hemodynamic pressure monitoring in a fluid-filled system. However, the relationship between the site level of a variable arterial pressure transducer and the pulse contour-derived parameters has yet to be established in critically ill patients. Moreover, the related quantitative analysis has never been investigated. Forty-two critically ill patients requiring PiCCO-Plus cardiac output monitoring were prospectively studied. The phlebostatic axis was defined as the zero reference level; the arterial pressure transducer was then vertically adjusted to different positions (+5, +10, +15, +20, -20, -15, -10, -5 cm) of departure from the zero reference site. The pulse contour waveform-derived parameters were recorded at each position. Elevation of the pressure transducer caused significantly positive changes in the continuous cardiac index (+CCI), stroke volume index (+SVI), and stroke volume variation (+SVV), and negative changes in the rate of left ventricular pressure rise during systole (-dP/dtmax), the systemic vascular resistance index (-SVRI), and vice versa. At the 5 cm position, the SVRI changes reached statistical significance with error. At the 10 cm position, the changes in CCI and dP/dtmax reached statistical significance with error, while the change in SVV reached statistical significance at 15 cm. The change rate of CCI was more than 5 % at the 15 cm position and approximately 10 % at the 20 cm position. On average, for every centimeter change of the transducer, there was a corresponding 0.014 L/min/m(2) CCI change and 0.36 % change rate, a 1.41 mmHg/s dP/dtmax change and 0.13 % change rate, and a 25 dyne/s/cm(5) SVRI change and 1.2 % change rate. The variation of arterial transducer position can result in inaccurate measurement of pulse contour waveform-derived parameters, especially when the transducer's vertical distance is more than 10 cm from the phlebostatic axis. These findings have clinical implications for continuous hemodynamic monitoring.


Assuntos
Pressão Arterial , Pulso Arterial , Transdutores , Adulto , Idoso , Artérias/patologia , Pressão Sanguínea , Débito Cardíaco , Cuidados Críticos/métodos , Estado Terminal , Feminino , Frequência Cardíaca , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/métodos , Pressão , Estudos Prospectivos , Reprodutibilidade dos Testes , Volume Sistólico , Sístole
6.
Artigo em Inglês | MEDLINE | ID: mdl-25904575

RESUMO

BACKGROUND: The central venous pressure (CVP) is essential for assessing the cardiac preload and circulating blood volume in clinic. The invasive CVP measurement by central venous catheter has been reported with various complications. The aim of this study was to develop a new noninvasive method for quantification of CVP by ultrasound. METHODS AND RESULTS: Seventy-six patients who had their CVP monitored for intraoperative or postoperative management were recruited. By accurate location of the collapse point of the internal jugular vein and the center of the right atrium using ultrasound imaging, the height of the fluid column between those 2 points was measured as the noninvasive CVP (CVPn). A total of 118 measurements were performed and compared with the invasive CVP (CVPi). Linear correlation analysis revealed a significant correlation between CVPi and CVPn (preoperative measurements, r=0.90; P<0.01 and postoperative measurements, r=0.93; P<0.01). Bland-Altman plots showed a good agreement between CVPi and CVPn with the mean difference of 0.22 mm Hg (preoperative measurements) and -0.09 mm Hg (postoperative measurements), respectively. CONCLUSIONS: The new noninvasive CVP quantification method based on the location of both the collapse point of internal jugular vein and the center of right atrium by ultrasound could be used as a reliable approach for monitoring the hemodynamic status in clinic.


Assuntos
Determinação da Pressão Arterial/métodos , Pressão Venosa Central/fisiologia , Cateterismo Venoso Central , Ecocardiografia , Estudos de Viabilidade , Feminino , Átrios do Coração/diagnóstico por imagem , Hemodinâmica , Humanos , Imageamento Tridimensional , Veias Jugulares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória , Interpretação de Imagem Radiográfica Assistida por Computador , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X
7.
Cancer Chemother Pharmacol ; 75(4): 861-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25732635

RESUMO

PURPOSE: Recent clinical trials showed that expression of excision repair cross-complementation group 1 (ERCC1), ribonucleotide reductase M1 (RRM1), and thymidylate synthase (TS) proteins was able to predict the effects of non-small cell lung cancer (NSCLC) to chemotherapy. However, it remains unknown whether the adjuvant chemotherapy based on expression of the three proteins has survival significance in Chinese NSCLC patients. METHODS: We investigated 128 Chinese patients receiving chemotherapy after tumor resection for expression of these proteins using immunohistochemistry. Based on protein expression, patients were assigned to two groups for different adjuvant chemotherapy regimes. The disease-free survival (DFS) data were collected and analyzed using Kaplan-Meier curves and Cox models. RESULTS: We found that DFS of these patients with carboplatin and a third-generation agent (gemcitabine or pemetrexed) stratified by protein expression showed no statistical difference between individual treatment versus non-individuation treatment analyzed using Kaplan-Meier method (P = 0.143, median 23.9 vs. 30.8 months). Furthermore, the multivariate analysis showed that histology and tumor stages were independent predictors for DFS in these patients. CONCLUSIONS: The results suggest that chemotherapy based on ERCC1, RRM1, and TS expression did not have significant impact on DFS of patients with resection of NSCLC.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas , Proteínas de Ligação a DNA/biossíntese , Endonucleases/biossíntese , Neoplasias Pulmonares , Timidilato Sintase/biossíntese , Proteínas Supressoras de Tumor/biossíntese , Idoso , Antineoplásicos/administração & dosagem , Biomarcadores Tumorais/metabolismo , Carboplatina/administração & dosagem , Carboplatina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Quimioterapia Adjuvante , China , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Intervalo Livre de Doença , Esquema de Medicação , Glutamatos/administração & dosagem , Glutamatos/uso terapêutico , Guanina/administração & dosagem , Guanina/análogos & derivados , Guanina/uso terapêutico , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/cirurgia , Masculino , Pemetrexede , Medicina de Precisão , Valor Preditivo dos Testes , Estudos Prospectivos , Ribonucleosídeo Difosfato Redutase
8.
J Exerc Sci Fit ; 13(2): 86-93, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29541104

RESUMO

Background/Objective: The aim of this study was to determine whether unilateral manual needling at nonacupoints could result in bilateral strength gain similar to that found in electroacupuncture at specific acupoints. Methods: Fifty healthy male volunteers with an age range of 19-27 years were recruited and randomly allocated into five groups: (1) manual acupuncture and (2) electroacupuncture at two acupoints (ST-36 and ST-39); (3) manual acupuncture and (4) electroacupuncture at two nonacupoints on the tibialis anterior muscle; and (5) control group. The intervention groups received needling in each session on the right leg for 15 minutes in Week 1, 20 minutes in Week 2, and 30 minutes in Weeks 3-8, three sessions per week. The maximal isometric ankle dorsiflexion strength and muscle activation (as determined by twitch interpolation) of both legs were assessed pre, post, 2 weeks post, and 3 weeks post the experimental period. Results: Mixed models (linear) with repeated-measures analysis identified significant strength gains (p < 0.01) after the intervention period in both limbs, while no significant differences were detected between the intervention groups and between the two legs, and no change was found in the control group. A significant improvement in muscle activation (p < 0.01) was also observed in both legs in the intervention groups. Conclusion: It was concluded that both unilateral manual and electric needling caused significant bilateral strength gain, and this effect was not specific to the selected acupoints or electric stimulation. The strength gain was sustained for at least 3 weeks after the 8-week intervention.

9.
Chin J Integr Med ; 16(6): 486-92, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21110172

RESUMO

OBJECTIVE: To evaluate the safety and efficacy of composite sophora colon-soluble capsule (CSCC) in treating ulcerative colitis (UC) of the damp-heat accumulation syndrome pattern (DHAS) and to prepare a basis for a phase III clinical trial. METHODS: A multi-center, randomized, single-blind, and positive drug parallel-controlled design was adopted. There were 126 patients of UC-DHAS stratified and assigned equally to three groups. Patients in two CSCC treated groups, Groups T1 and T2, were treated orally with high (six capsules, thrice a day) and low (four capsules, thrice a day) doses CSCC, and patients in the control group were treated orally with Mesalazine Enteric-coated Tablets (four tablets, thrice a day), respectively, all for eight weeks. The clinical efficacy and safety of treatments were evaluated through clinical symptom observations and colonoscopic examinations. RESULTS: (1) Full analysis set (FAS) and per-protocol set (PPS) analyses showed the comprehensive curative effect in Groups T1, T2, and the control group, obtaining the values of 85.7%, 92.9%, and 71.4% (P=0.330), and 89.5%, 92.7%, and 73.2% (P=0.552), respectively, demonstrating no statistical significance among the three groups. (2) FAS and PPS analysis showed the efficacy on membranous lesions in Groups T1, T2, and the control group, obtaining the values of 83.3%, 92.9%, and 73.8% (P=0.063), and 86.8%, 92.7%, and 75.6% (P=0.070), respectively, showing statistical insignificance among the three groups. (3) FAS analysis showed an efficacy tendency on improving tenesmus (P=0.056). No changes were found in improving the other symptoms, and statistical significance was not shown among the three groups (P>0.05). PPS analysis showed the efficacy on single item symptom in Groups T1, T2, and the control group was not statistically significant among the three groups (P=0.082). CONCLUSIONS: The comprehensive effect of CSCC in treating UC is basically equivalent to that of Mesalazine enteric-coated tablet; however, the tendency was shown to improve symptoms. Its efficacy could not be raised by increasing the dosage used. Therefore, the recommended dosage of CSCC is four capsules, three times a day.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Colo/patologia , Extratos Vegetais/uso terapêutico , Sophora/química , Adulto , Cápsulas , Colo/efeitos dos fármacos , Feminino , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Masculino , Medicina Tradicional Chinesa , Extratos Vegetais/efeitos adversos , Extratos Vegetais/farmacologia , Método Simples-Cego , Resultado do Tratamento
10.
Int J Syst Evol Microbiol ; 59(Pt 6): 1326-30, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19502310

RESUMO

The taxonomic position of an actinomycete isolated from a lead-polluted soil in Gansu province, north-west China, was determined by using a polyphasic approach. Chemical and morphological properties of the isolate, designated strain CCNWHX 13-160(T), were similar to those of streptomycetes. Analysis of the almost complete 16S rRNA gene sequence placed strain CCNWHX 13-160(T) in the genus Streptomyces where it formed a distinct phyletic line with recognized Streptomyces species. The strain was most similar to Streptomyces pseudovenezuelae NBRC 12904(T) (98.9 %) and Streptomyces resistomycificus NBRC 12814(T) (98.8 %). Furthermore, DNA-DNA hybridization studies between the novel isolate and these two strains showed relatedness values of 49.7+/-0.8 and 43.2+/-1.1 %, respectively. It is proposed that strain CCNWHX 13-160(T) (=ACCC 41207(T)=HAMBI 2991(T)) be classified as the type strain of a novel species in the genus Streptomyces, Streptomyces plumbiresistens sp. nov. The MIC of Pb(2+) for growth of strain CCNWHX 13-160(T) was 4.0 mM.


Assuntos
Farmacorresistência Bacteriana , Chumbo/farmacologia , Microbiologia do Solo , Poluentes do Solo/farmacologia , Streptomyces/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/análise , DNA Ribossômico/análise , Genótipo , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/efeitos dos fármacos , Streptomyces/genética , Streptomyces/isolamento & purificação
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