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1.
J Chem Inf Model ; 64(2): 340-347, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38166383

RESUMEN

Protein thermodynamic stability is essential to clarify the relationships among structure, function, and interaction. Therefore, developing a faster and more accurate method to predict the impact of the mutations on protein stability is helpful for protein design and understanding the phenotypic variation. Recent studies have shown that protein embedding will be particularly powerful at modeling sequence information with context dependence, such as subcellular localization, variant effect, and secondary structure prediction. Herein, we introduce a novel method, ProSTAGE, which is a deep learning method that fuses structure and sequence embedding to predict protein stability changes upon single point mutations. Our model combines graph-based techniques and language models to predict stability changes. Moreover, ProSTAGE is trained on a larger data set, which is almost twice as large as the most used S2648 data set. It consistently outperforms all existing state-of-the-art methods on mutation-affected problems as benchmarked on several independent data sets. The protein embedding as the prediction input achieves better results than the previous results, which shows the potential of protein language models in predicting the effect of mutations on proteins. ProSTAGE is implemented as a user-friendly web server.


Asunto(s)
Redes Neurales de la Computación , Proteínas , Proteínas/genética , Proteínas/química , Estabilidad Proteica , Estructura Secundaria de Proteína , Mutación
2.
BMC Anesthesiol ; 23(1): 331, 2023 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-37794331

RESUMEN

BACKGROUND: Based on electroencephalogram (EEG) analysis, index of consciousness (IoC) monitoring is a new technique for monitoring anesthesia depth. IoC is divided into IoC1 (depth of sedation) and IoC2 (depth of analgesia). The potential for concurrent monitoring of IoC1 and IoC2 to expedite postoperative convalescence remains to be elucidated. We investigated whether combined monitoring of IoC1 and IoC2 can effectively enhances postoperative recovery compared with bispectral index (BIS) in elderly patients undergoing laparoscopic urological surgery under general anesthesia. METHODS: In this prospective, controlled, double-blinded trail, 120 patients aged 65 years or older were arbitrarily assigned to either the IoC group or the control group (BIS monitoring). All patients underwent blood gas analysis at T1 (before anesthesia induction) and T2 (the end of operation). The Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) were administered to all patients at T0 (1 day before surgery) and T4 (7 days after surgery). Serum concentrations of C-reactive protein (CRP) and glial fibrillary acid protein (GFAP) were assessed at T1, T2, and T3 (24 h after surgery). Postoperative complications and the duration of hospitalization were subjected to comparative evaluation. RESULTS: The incidence of postoperative cognitive dysfunction (POCD) was notably lower in the IoC group (10%) than in the control group (31.7%) (P = 0.003). Postoperative serum CRP and GFAP concentrations exhibited significant differences at time points T2 (CRP: P = 0.000; GFAP: P = 0.000) and T3 (CRP: P = 0.003; GFAP: P = 0.008). Postoperative blood glucose levels (P = 0.000) and the overall rate of complications (P = 0.037) were significantly lower in Group IoC than in Group control. CONCLUSION: The employment of IoC monitoring for the management of elderly surgical patients can accelerate postoperative convalescence by mitigating intraoperative stress and reducing peripheral and central inflammatory injury. TRIAL REGISTRATION: Chinese Clinical Trial Registry Identifier: ChiCTR1900025241 (17/08/2019).


Asunto(s)
Convalecencia , Laparoscopía , Anciano , Humanos , Estado de Conciencia , Estudios Prospectivos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Proteína C-Reactiva/metabolismo , Anestesia General/métodos
3.
Analyst ; 147(9): 1976-1985, 2022 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-35419580

RESUMEN

Hypochlorous acid (HOCl) is widely used in daily production and life because of its green and strongly oxidizing properties. Additionally, as a vital reactive oxygen species (ROS), it is an innate immune system weapon and performs a critical function in many pathophysiology processes. In this paper, a novel water-soluble fluorescent probe, BMH, with excellent performance is designed and synthesized by simple condensation of benzocoumarin and 2-mercaptoethanol. BMH has specific selectivity, excellent sensitivity, ultra-fast response (<3 s), and a wide pH detection range. The fluorescence intensity of BMH has an excellent linear correlation with the concentration of HOCl in the scope of 0-10 µM, and the calculated detection limit (DL) is 2.45 nM. The intramolecular charge transfer (ICT) sensing mechanism of BL has been verified by fluorescence, UV, and MS studies as well as density functional theory (DFT) calculations. Furthermore, BMH can be incorporated into a solid-state visual sensor to detect HOCl conveniently. BMH was applied to detect HOCl-spiked actual water samples and achieved satisfying recovery rates. Also, the low-toxicity BMH can be successfully used to track changes in endogenous/exogenous HOCl in living cells. In short, BL provides a robust and reliable monitoring tool to reveal the biological functions of HOCl and ensure its safe use.


Asunto(s)
Colorantes Fluorescentes , Ácido Hipocloroso , Fluorescencia , Colorantes Fluorescentes/química , Colorantes Fluorescentes/toxicidad , Ácido Hipocloroso/química , Agua/química
4.
Clin Exp Pharmacol Physiol ; 49(2): 264-274, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34570396

RESUMEN

Propofol, a widely used short-acting intravenous sedative agent, has gradually gained attention due to the tumour-suppressing role and non-anaesthetic effect. Dysfunction of metabolic reprogramming has been recognised as a well-documented factor for tumour progression. The aim of this study is to explore the effect of propofol on the polyol pathway in gastric cancer cells. In this study, we found that propofol treatment led to a significant downregulation of cell proliferation in BGC823 and GES-1 cells, which was attributed to the decreased AR-mediated polyol pathway. Both aldo-keto reductase family 1, member B1 (AKR1B1) and AKR1B10 were significantly reduced in BGC823 and GES-1 cells in response to propofol stimulation, leading to decreased AR activity and sorbitol level. Addition of sorbitol could reverse the inhibitory effect of propofol on cell proliferation. Mechanically, propofol treatment drastically inhibited phosphorylation and nuclear translocation of nuclear factor (erythroid-derived 2)-like 2 (NRF2), subsequently decreased the binding of NRF2 to AR promoter. Overexpression of NRF2 resulted in the recovery of AR expression in gastric cancer cell with propofol treatment. Taken together, these finding showed that propofol suppressed cell proliferation in BGC823 and GES-1 cell through NRF2-mediated polyol pathway, which would aid the selection of sedation for patients with gastric cancer.


Asunto(s)
Propofol , Neoplasias Gástricas , Aldehído Reductasa/farmacología , Línea Celular Tumoral , Proliferación Celular , Humanos , Factor 2 Relacionado con NF-E2/metabolismo , Polímeros , Propofol/farmacología , Neoplasias Gástricas/tratamiento farmacológico
5.
World J Surg Oncol ; 20(1): 192, 2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35689233

RESUMEN

BACKGROUND: Microwave ablation (MWA) is a potentially curative treatment for unresectable patients with hepatocellular carcinoma (HCC) ≤ 3 cm, while its therapeutic efficacy decreases significantly for HCC > 3cm. Previous studies have demonstrated that conventional transarterial chemoembolization (cTACE) combined with MWA (cTACE-MWA) may improve local tumor control rate and reduce the recurrence rate for HCC > 3cm. However, there have been few study designs to analyze the clinical efficacy of cTACE-MWA for medium-sized HCC (3-5cm). Therefore, this study aims to compare the clinical efficacy and safety of cTACE-MWA with cTACE alone for a single medium-sized HCC of 3-5 cm in diameter. METHODS: We retrospectively investigate the data of 90 patients with a single medium-sized HCC who were referred to our hospital and underwent cTACE-MWA or cTACE alone from December 2017 to March 2020. Then, patients were identified with propensity score-matched (1:1). The local tumor response to treatment and time to progression (TTP) were compared using mRECIST criteria between the cTACE-MWA group and the cTACE group. RESULTS: A total of 42 patients were included after matching (cTACE-MWA: 21; cTACE: 21). Comparing with cTACE, cTACE-MWA demonstrate significantly better local tumor control (ORR: 95.2% vs 61.9%, p = 0.02; DCR: 95.2% vs 66.7%, p = 0.045) and TTP (median 19.8 months vs 6.8 months, p < 0.001). The 1- and 2-year cumulative probabilities of OS were 100% and 95% in the cTACE-MWA group, which were significantly higher than those in the cTACE group (95% and 76%) (p = 0.032). Multivariate Cox regression analysis illustrates that cTACE-MWA was associated with better TTP (hazard ratio, 0.28; 95% CI: 0.1, 0.76; p = 0.012), but tumor size was associated with worse TTP (hazard ratio, 1.71; 95% CI: 1.01, 2.89; p = 0.045). CONCLUSIONS: cTACE followed by MWA improved TTP and OS in patients with a single medium-sized HCC, and no major complication was observed in this study.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/patología , Terapia Combinada , Humanos , Neoplasias Hepáticas/cirugía , Microondas/uso terapéutico , Puntaje de Propensión , Estudios Retrospectivos , Resultado del Tratamiento
6.
Zhongguo Zhong Yao Za Zhi ; 47(6): 1546-1557, 2022 Mar.
Artículo en Zh | MEDLINE | ID: mdl-35347952

RESUMEN

Zhachong Shisanwei Pills, composed of 13 Chinese medicinal materials, are used for treating the diseases such as hemiplegia, pain of muscles and bones, rheumatism, and joint pain. The chemical composition and pharmacodynamics of Zhachong Shisanwei Pills have not been reported. Ultra-performance liquid chromatography/quadrupole-time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MS/MS) was employed to quickly identify the chemical components of Zhachong Shisanwei Pills, which was performed with Shim-pack GIST C_(18) column(4.6 mm×150 mm, 5 µm). The gradient elution was conducted with methanol-0.05% acetic acid as the mobile phase. Electrospray ionization mass spectrometry(ESI-MS) was carried out in both positive and negative ion modes. The compounds were identidied based on accurate relative molecular weight, fragment ion species, and the MS data of reference substances and in literature. In conclusion, a total of 98 compounds were identified, including 19 organic acids, 36 flavonoids, 13 volatile oils, 8 tannins, 5 2-(2-phenylethyl)chromones, 5 amino acids, 3 sesquiterpenoids, 3 alkaloids, and 2 other compounds. This study characte-rized the chemical components of Zhachong Shisanwei Pills rapidly for the first time, laying a foundation for further research on the pharmacodynamic material basis and quality evaluation.


Asunto(s)
Medicamentos Herbarios Chinos , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Medicamentos Herbarios Chinos/química , Espectrometría de Masa por Ionización de Electrospray
7.
Clin Sci (Lond) ; 135(14): 1733-1750, 2021 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-34236078

RESUMEN

Chronic obstructive pulmonary disease (COPD) is a worldwide chronic inflammatory lung disease, and influenza A virus (IAV) infection is a common cause of acute exacerbations of COPD (AECOPD). Therefore, targeting viral infections represents a promising strategy to prevent the occurrence and development of inflammatory flare ups in AECOPD. Jianpiyifei II (JPYFII) is a traditional herbal medicine used in China to treat patients with COPD, and its clinical indications are not well understood. However, investigation of the anti-inflammatory effects and underlying mechanism using an animal model of smoking have been reported in a previous study by our group. In addition, some included herbs, such as Radix astragali and Radix aupleuri, were reported to exhibit antiviral effects. Therefore, the aim of the present study was to investigate whether JPYFII formulation relieved acute inflammation by clearing the IAV in a mouse model that was exposed to cigarette smoke experimentally. JPYFII formulation treatment during smoke exposure and IAV infection significantly reduced the number of cells observed in bronchoalveolar lavage fluid (BALF), expression of proinflammatory cytokines, chemokines, superoxide production, and viral load in IAV-infected and smoke-exposed mice. However, JPYFII formulation treatment during smoke exposure alone did not reduce the number of cells in BALF or the expression of Il-6, Tnf-a, and Il-1ß. The results demonstrated that JPYFII formulation exerted an antiviral effect and reduced the exacerbation of lung inflammation in cigarette smoke (CS)-exposed mice infected with IAV. Our results suggested that JPYFII formulation could potentially be used to treat patients with AECOPD associated with IAV infection.


Asunto(s)
Medicina de Hierbas , Virus de la Influenza A/patogenicidad , Neumonía/terapia , Enfermedad Pulmonar Obstructiva Crónica/terapia , Animales , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Gripe Humana/complicaciones , Pulmón/metabolismo , Ratones Endogámicos BALB C , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Humo/efectos adversos , Fumar/efectos adversos
8.
Mol Cell Probes ; 53: 101572, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32525042

RESUMEN

Endometrial carcinoma (EC) is a female-specific malignant tumor. Although current treatments can achieve good outcomes and improve patient survival, there remains a high incidence of treatment-induced infertility, a serious side effect that is unacceptable to those of childbearing age. Studies have demonstrated that micro ribonucleic acids (microRNAs or miRNAs) such as miR-544a regulate tumor-related gene expression. However, whether miR-544a is involved in the progression of EC is unknown. This study aimed to investigate the biological functions and underlying mechanisms of miR-544a in EC in vivo and in vitro. Quantitative real-time polymerase chain reaction (qRT-PCR) revealed miR-544a overexpression in EC tissue and cell lines, which was associated with a decreased in overall survival as revealed by Kaplan-Meier analysis. Functionally, the miR-544a inhibitor restricted the proliferation [detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay], invasion, and migration (detected by transwell assay) of human endometrial adenocarcinoma cells (HEC-1B and Ishikawa) and facilitated cell apoptosis (detected by flow cytometry assay). Western blotting analysis revealed that the miR-544a inhibitor decreased the expressions of matrix metalloproteinase (MMP)-2 and MMP-9 and elevated the levels of cleaved caspase3 and cleaved poly (ADP-ribose) polymerase. Furthermore, animal experiments indicated that the miR-544a antagonist (antagomir-544a) suppressed tumor growth significantly in a mouse xenograft model. The mechanistic, qRT-PCR, and immunohistochemical indications were that a reversion-inducing cysteine-rich protein with Kazal motifs (RECK) and miR-544a had inverse expression changes in EC. Bioinformatics analysis revealed RECK as a potential target for miR-544a, and this was verified by the dual-luciferase reporter assay. Subsequently, in vitro experiments, including transwell assay, MTT assay, flow cytometry assay, and Western blotting analysis, demonstrated that RECK exerted antitumor effects on EC, which were negatively regulated by miR-544a. Taken together, our study findings suggested miR-544a as a valuable target in EC therapy.


Asunto(s)
Neoplasias Endometriales/patología , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , MicroARNs/genética , Animales , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Neoplasias Endometriales/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Trasplante de Neoplasias , Análisis de Supervivencia , Regulación hacia Arriba
9.
Nanotechnology ; 31(33): 335717, 2020 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-32375129

RESUMEN

N-doped carbon-based materials are crucial electrically conductive additives and non-metal electrocatalysts for the oxygen reduction reaction. At present, many pieces of research are focused on the effects of micropore, mesopore and hierarchical pore structure on the catalytic activity, however, there are few works concerning the role of large-dimension through-hole structure. Hence, in this work, we prepare two kinds of carbon materials with large through-hole structure, i.e. N-doped carbon hollow-spheres and hollow-tubes, as the oxygen reduction catalysts. The synthesis follows template-free morphology-controlled pyrolysis, which is more convenient than the preparation of conventional N-doped nanotubes and graphene. The resultant N-doped carbon hollow-spheres and hollow-tubes evidently enhanced their ORR catalytic activity, remarkable long-term stability and methanol resistance. The large-dimension through-hole structure is found to account for the increase in mass transfer.

10.
BMC Womens Health ; 20(1): 125, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32546170

RESUMEN

BACKGROUND: For a long time, the relationship between caffeine consumption and infertility in the general population is unclear, this study is aimed to systematically review the evidence from any type of controlled clinical studies to explore whether caffeine intake is a risk factor for human infertility. METHODS: Seven databases were searched from inception to May 2019. We included women/men without a history of infertility but were willing to have children in prospective studies and women/men who were diagnosed with infertility in retrospective studies. The observed exposure factor should be caffeine or caffeine containing beverage. Diagnosis of infertility or not for participants was the key outcome. The Newcastle-Ottawa scale (NOS) or Cochrane risk of bias tool were used to assess the methodological quality of included studies. Meta-analysis was conducted if there were acceptable clinical and statistical heterogeneity among studies. The GRADE method was used to assess the certainty of the evidence. RESULTS: Four studies (one cohort study and three case-control studies) involving 12,912 participants were included. According NOS, the average score of case-control studies was 6, and the cohort study achieved 9. Meta-analysis and subgroup analysis were conducted. The results showed that low (OR 0.95, 95%CI 0.78-1.16), medium (OR 1.14, 95%CI 0.69-1.86) and high doses (OR 1.86, 95%CI 0.28-12.22) of caffeine intake may not increase the risk of infertility. The quality of the current evidence bodies were all low. CONCLUSION: Our study provides low quality evidence that regardless of low, medium and high doses of caffeine intake do not appear increase the risk of infertility. But the conclusion should be treated with caution.


Asunto(s)
Cafeína/efectos adversos , Fertilidad/efectos de los fármacos , Infertilidad Femenina/inducido químicamente , Cafeína/administración & dosificación , Niño , Ensayos Clínicos Controlados como Asunto , Femenino , Humanos , Masculino , Embarazo
11.
BMC Plant Biol ; 19(1): 469, 2019 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-31690290

RESUMEN

BACKGROUND: Soybean (Glycine max (L.)) is one the most important oil-yielding cash crops. However, the soybean production has been seriously restricted by salinization. It is therefore crucial to identify salt tolerance-related genes and reveal molecular mechanisms underlying salt tolerance in soybean crops. A better understanding of how plants resist salt stress provides insights in improving existing soybean varieties as well as cultivating novel salt tolerant varieties. In this study, the biological function of GmNHX1, a NHX-like gene, and the molecular basis underlying GmNHX1-mediated salt stress resistance have been revealed. RESULTS: We found that the transcription level of GmNHX1 was up-regulated under salt stress condition in soybean, reaching its peak at 24 h after salt treatment. By employing the virus-induced gene silencing technique (VIGS), we also found that soybean plants became more susceptible to salt stress after silencing GmNHX1 than wild-type and more silenced plants wilted than wild-type under salt treatment. Furthermore, Arabidopsis thaliana expressing GmNHX1 grew taller and generated more rosette leaves under salt stress condition compared to wild-type. Exogenous expression of GmNHX1 resulted in an increase of Na+ transportation to leaves along with a reduction of Na+ absorption in roots, and the consequent maintenance of a high K+/Na+ ratio under salt stress condition. GmNHX1-GFP-transformed onion bulb endothelium cells showed fluorescent pattern in which GFP fluorescence signals enriched in vacuolar membranes. Using the non-invasive micro-test technique (NMT), we found that the Na+ efflux rate of both wild-type and transformed plants after salt treatment were significantly higher than that of before salt treatment. Additionally, the Na+ efflux rate of transformed plants after salt treatment were significantly higher than that of wild-type. Meanwhile, the transcription levels of three osmotic stress-related genes, SKOR, SOS1 and AKT1 were all up-regulated in GmNHX1-expressing plants under salt stress condition. CONCLUSION: Vacuolar membrane-localized GmNHX1 enhances plant salt tolerance through maintaining a high K+/Na+ ratio along with inducing the expression of SKOR, SOS1 and AKT1. Our findings provide molecular insights on the roles of GmNHX1 and similar sodium/hydrogen exchangers in regulating salt tolerance.


Asunto(s)
Glycine max/metabolismo , Proteínas de Plantas/metabolismo , Tolerancia a la Sal/genética , Plantas Tolerantes a la Sal/metabolismo , Intercambiadores de Sodio-Hidrógeno/metabolismo , Arabidopsis/genética , Silenciador del Gen , Proteínas de Plantas/genética , Potasio/metabolismo , Plantas Tolerantes a la Sal/genética , Sodio/metabolismo , Intercambiadores de Sodio-Hidrógeno/genética , Glycine max/genética , Estrés Fisiológico/genética , Regulación hacia Arriba , Vacuolas/metabolismo
12.
Plant Biotechnol J ; 17(2): 397-409, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29992702

RESUMEN

Morella rubra, red bayberry, is an economically important fruit tree in south China. Here, we assembled the first high-quality genome for both a female and a male individual of red bayberry. The genome size was 313-Mb, and 90% sequences were assembled into eight pseudo chromosome molecules, with 32 493 predicted genes. By whole-genome comparison between the female and male and association analysis with sequences of bulked and individual DNA samples from female and male, a 59-Kb region determining female was identified and located on distal end of pseudochromosome 8, which contains abundant transposable element and seven putative genes, four of them are related to sex floral development. This 59-Kb female-specific region was likely to be derived from duplication and rearrangement of paralogous genes and retained non-recombinant in the female-specific region. Sex-specific molecular markers developed from candidate genes co-segregated with sex in a genetically diverse female and male germplasm. We propose sex determination follow the ZW model of female heterogamety. The genome sequence of red bayberry provides a valuable resource for plant sex chromosome evolution and also provides important insights for molecular biology, genetics and modern breeding in Myricaceae family.


Asunto(s)
Evolución Molecular , Genoma de Planta/genética , Myrica/genética , Mapeo Cromosómico , Flores/genética , Flores/crecimiento & desarrollo , Flores/fisiología , Frutas/genética , Frutas/crecimiento & desarrollo , Frutas/fisiología , Marcadores Genéticos/genética , Anotación de Secuencia Molecular , Myrica/crecimiento & desarrollo , Myrica/fisiología , Especificidad de Órganos , Fitomejoramiento
13.
Macromol Rapid Commun ; 39(12): e1700714, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29749065

RESUMEN

Development of two-way shape memory polymers that operate free of external force remains a great challenge. Here, the design criteria for this type of material are proposed, deriving a novel fabrication strategy accordingly, which employs conventional crosslinked polyurethane (PU) containing crystalline poly(ε-caprolactone) (PCL) as the proof-of-concept material. Having been simply trained by stretching and thermal treatment without additional ingredients and chemicals, the PU is coupled with a two-way shape memory effect. The core advancement of this study lies in the successful conversion of the inherent hydrogen bond network, which is often the easiest to overlook, into an internal stress provider. The temperature-dependent reversible melting/recrystallization of the crystalline phases elaborately works with the tensed hydrogen bond network, leading to implementation of the two-way shape memory effect. An average reversible strain of as high as ≈20% along the stretch direction is obtained through cooperation adjustment of chemical crosslinking density, crystallinity, and concentration of hydrogen bonds. Meanwhile, the highest internal tension offered by the hydrogen bond network is determined to be 0.10 MPa. Owing to the great convenience characterized by material selection, preparation, programming, and application, the current work may open up an avenue for production and usage of the smart material.


Asunto(s)
Materiales Biocompatibles/química , Poliésteres/química , Polímeros/química , Poliuretanos/química , Materiales Biocompatibles/síntesis química , Cristalización , Enlace de Hidrógeno , Estructura Molecular , Polímeros/síntesis química , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
14.
J Nanosci Nanotechnol ; 18(9): 6244-6248, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29677774

RESUMEN

Silica nanoparticles were ozone-treated to increase the dispersibility of silica in a silicone matrix. Silicone rubber/silica composites were prepared using a melt-blending method. The effect of silica content on the mechanical and thermal properties of the silica-reinforced silicone composites was examined. The tensile strength of the prepared silicone/silica composites was maximized at 1 wt.% silica, due to the improved interfacial interactions between the silica reinforcement surface and the silicone matrix. The thermal stability of the composites was significantly enhanced with increasing silica content.

15.
Curr Opin Anaesthesiol ; 31(1): 24-29, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29120931

RESUMEN

PURPOSE OF REVIEW: The extrinsic risk factors for postoperative cognitive disturbance have been a source of concern during the perioperative period, and these risk factors remain the subject of controversy. This review of recent studies focuses on the effect of these factors on postoperative cognitive disturbance during the perioperative period. RECENT FINDINGS: Impairment of cerebral autoregulation may predispose patients to intraoperative cerebral malperfusion, which may subsequently induce postoperative cognitive disturbance. The neurotoxicity of several volatile anesthetics may contribute to cognitive functional decline, and the impact of intravenous anesthesia on cognitive function requires further exploration. Multimodal analgesia may not outperform traditional postoperative analgesia in preventing postoperative delirium. Furthermore, acute pain and chronic pain may exacerbate the cognitive functional decline of patients with preexisting cognitive impairment. The nuclear factor-kappa beta pathway is an important node in the neuroinflammatory network. SUMMARY: Several intraoperative factors are associated with postoperative cognitive disturbance. However, if these factors are optimized in perioperative management, postoperative cognitive disturbance will improve.


Asunto(s)
Trastornos del Conocimiento/etiología , Complicaciones Posoperatorias/etiología , Anciano , Anestésicos/efectos adversos , Hemodinámica , Humanos , Manejo del Dolor
16.
Mol Pain ; 13: 1744806917740681, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29056068

RESUMEN

Abstract: Metastatic bone tumor-induced changes in gene transcription and translation in pain-related regions of the nervous system may participate in the development and maintenance of bone cancer pain. Epigenetic modifications including DNA methylation regulate gene transcription. Here, we report that intrathecal injection of decitabine, a DNA methyltransferase (DNMT) inhibitor, dose dependently attenuated the development and maintenance of bone cancer pain induced by injecting prostate cancer cells into the tibia. The level of the de novo DNMT3a, but not DNMT3b, time dependently increased in the ipsilateral L4/5 dorsal horn (not L4/5 dorsal root ganglion) after prostate cancer cells injection. Blocking this increase through microinjection of recombinant adeno-associated virus 5 (AAV5) expressing Dnmt3a shRNA into dorsal horn rescued prostate cancer cells-induced downregulation of dorsal horn Kv1.2 expression and impaired prostate cancer cells-induced pain hypersensitivity. In turn, mimicking this increase through microinjection of AAV5 expressing full-length Dnmt3a into dorsal horn reduced dorsal horn Kv1.2 expression and produced pain hypersensitivity in the absence of prostate cancer cells injection. Administration of neither decitabine nor virus affected locomotor function and acute responses to mechanical, thermal, or cold stimuli. Given that Dnmt3a mRNA is co-expressed with Kcna2 mRNA (encoding Kv1.2) in individual dorsal horn neurons, our findings suggest that increased dorsal horn DNMT3a contributes to bone cancer pain through silencing dorsal horn Kv1.2 expression. DNMT3a may represent a potential new target for cancer pain management.


Asunto(s)
Dolor en Cáncer/fisiopatología , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Canal de Potasio Kv.1.2/metabolismo , Asta Dorsal de la Médula Espinal/metabolismo , Animales , Dolor en Cáncer/metabolismo , ADN Metiltransferasa 3A , Modelos Animales de Enfermedad , Ganglios Espinales/metabolismo , Masculino , Dolor Musculoesquelético/metabolismo , Dolor Musculoesquelético/fisiopatología , Células del Asta Posterior/metabolismo , Ratas , Asta Dorsal de la Médula Espinal/fisiopatología
17.
J Fluoresc ; 27(4): 1331-1337, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28353208

RESUMEN

In this study, the coumarin-derived schiff bases (HL1 and HL2) have been designed and synthesized. Upon the addition of Zn2+, both of them show significant fluorescence enhancement owing to inhibits PET and ESIPT process respectively. However, the receptor HL2 response toward Cd2+, Mg2+, Ba2+, Ca2+ besides Zn2+ and exhibits fluorescence enhancement but not enough to detection of the concentration levels of Zn2+.

18.
Macromol Rapid Commun ; 38(16)2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28627040

RESUMEN

The present communication reports a novel strategy to fabricate reversible shape-memory polymer that operates without the aid of external force on the basis of a two-phase structure design. The proof-of-concept material, crosslinked styrene-butadiene-styrene block copolymer (SBS, dispersed phase)/polycaprolactone-based polyurethane (PU, continuous phase) blend, possesses a closely connected microphase separation structure. That is, SBS phases are chemically bonded to crosslinked PU by means of a single crosslinking agent and two-step crosslinking process for increasing integrity of the system. Miscibility between components in the blend is no longer critical by taking advantage of the reactive blending technique. It is found that a suitable programming leads to compressed SBS, which serves as internal expansion stress provider as a result. The desired two-way shape-memory effect is realized by the joint action of the temperature-induced reversible opposite directional deformabilities of the crystalline phase of PU and compressed SBS, accompanying melting and orientated recrystallization of the former. Owing to the broadness of material selection and manufacturing convenience, the proposed approach opens an avenue toward mass production and application of the smart polymer.


Asunto(s)
Técnicas de Química Analítica , Polímeros/síntesis química , Elastómeros , Fenómenos Mecánicos , Poliuretanos/química , Estirenos/química , Temperatura
19.
Nano Lett ; 16(10): 6568-6575, 2016 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-27618435

RESUMEN

Surface defects in relation to surface compositions, morphology, and active sites play crucial roles in photocatalytic activity of graphitic carbon nitride (g-C3N4) material for highly reactive oxygen radicals production. Here, we report a high-efficiency carbon nitride supramolecular hybrid material prepared by patching the surface defects with inorganic clusters. Fe (III) {PO4[WO(O2)2]4} clusters have been noncovalently integrated on surface of g-C3N4, where the surface defects provide accommodation sites for these clusters and driving forces for self-assembly. During photocatalytic process, the activity of supramolecular hybrid is 1.53 times than pure g-C3N4 for the degradation of Rhodamine B (RhB) and 2.26 times for Methyl Orange (MO) under the simulated solar light. Under the mediation of H2O2 (50 mmol L-1), the activity increases to 6.52 times for RhB and 28.3 times for MO. The solid cluster active sites with high specific surface area (SSA) defect surface promoting the kinetics of hydroxide radicals production give rise to the extremely high photocatalytic activity. It exhibits recyclable capability and works in large-scale demonstration under the natural sunlight as well and interestingly the environmental temperature has little effects on the photocatalytic activity.

20.
J Fluoresc ; 26(3): 1059-65, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27048223

RESUMEN

A new chromone Schiff-base fluorescent probe 7'-methoxychromone-3'-methylidene-1,2,4-triazole-3-imine (L) was designed and synthesized for selective recognition Cd(2+). With the fluorescence titration and the ESI-MS data, we reach the conclusion that the binding mode of the ligand-metal (L-Cd (2+) ) complex is 1:1. The sensor showed a strong fluorescence enhancement in ethanol system of Cd(2+) (excitation 409 nm and emission 462 nm) and the sensing mechanism based on the fact that C=N isomerization can be used to explain this phenomenon.

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