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1.
Bioorg Chem ; 143: 107014, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38061180

RESUMEN

Many pathological processes include nitric oxide (NO), a signaling transduction molecule. Tumors, cardiovascular, cerebrovascular, neurodegenerative, and other illnesses are linked to abnormal NO levels. Thus, evaluating NO levels in vitro and in vivo is crucial for studying chemical biology process of associated disorders. This work devised and manufactured a coumarin-based fluorescent probe ZPS-NO to detect nitric oxide (NO). The reaction between ZPS-NO and NO produced a highly selective and sensitive optical response that caused a powerful fluorescence "turn-on" effect with a ultra-low NO detection limit of 14.5 nM. Furthermore, the probe was applied to sense and image NO in living cells and inflammatory model of zebrafish, as well as to detect NO in periodontitis patients' saliva samples. We anticipate that probe ZPS-NO will serve as a practical and effective tool for assessing the interactions and evaluation of periodontitis development.


Asunto(s)
Colorantes Fluorescentes , Pez Cebra , Animales , Humanos , Colorantes Fluorescentes/química , Óxido Nítrico , Saliva , Células HeLa , Biomarcadores
2.
Anal Chem ; 92(19): 13336-13342, 2020 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-32809800

RESUMEN

As the most common malignancy in humans, oral squamous cell carcinoma (OSCC) not only harms the people's health but also undermines their confidence after facial surgery. Early detection and treatment can effectively reduce these damages. The unique collateral trans-cleavage nuclease activity of clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a system was utilized to realize the detection of nucleic acid with high sensitivity. So, in this work, we designed a point-of-care testing (POCT) platform for the detection of OSCC-associated salivary hsa-miRNA 31-5p (miR-31) via the cascade signal amplification of "invading stacking primer" (IS-primer) amplification reaction (ISAR), CRISPR/Cas12a, and dual-mode paper-based strip (dm-Strip). To amplify the detection signal of trace miR-31, the cascade signal amplification of CRISPR/Cas12a system coupling with ISAR was designed in a one-pot reaction at a constant temperature. The target miR-31 could activate the ISAR to generate numerous DNAs, which would further trigger the trans-cleavage effect of Cas12a to catalyze the nonspecific single-stranded DNA (ssDNA) cleavage. This ssDNA was labeled with digoxin and biotin at the 5' and 3' termini (digoxin/ssDNA/biotin), respectively, which led to generate the naked-eye signal and fluorescent signal of the designed dm-Strip. The whole detection time was 90 min with limit-of-detection (LOD) down to aM level. This ISAR/Cas12a-based dm-Strip (ISAR/Cas12a-dmStrip) allowed for the portable and ultrasensitive detection of miRNA, an important step in early diagnosis of OSCC and biomedical research.


Asunto(s)
Neoplasias de Cabeza y Cuello/diagnóstico , MicroARNs/análisis , Técnicas de Amplificación de Ácido Nucleico , Papel , Tiras Reactivas/química , Saliva/química , Carcinoma de Células Escamosas de Cabeza y Cuello/diagnóstico , Proteínas Bacterianas/genética , Proteínas Asociadas a CRISPR/genética , Sistemas CRISPR-Cas/genética , Endodesoxirribonucleasas/genética , Humanos , MicroARNs/genética
3.
Acta Biomater ; 182: 14-27, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38750918

RESUMEN

The powerful adhesion systems of marine organisms have inspired the development of artificial protein-based bioadhesives. However, achieving robust wet adhesion using artificial bioadhesives remains technically challenging because the key element of liquid-liquid phase separation (LLPS)-driven complex coacervation in natural adhesion systems is often ignored. In this study, mimicking the complex coacervation phenomenon of marine organisms, an artificial protein-based adhesive hydrogel (SFG hydrogel) was developed by adopting the LLPS-mediated coacervation of the natural protein silk fibroin (SF) and the anionic surfactant sodium dodecylbenzene sulfonate (SDBS). The assembled SF/SDBS complex coacervate enabled precise spatial positioning and easy self-adjustable deposition on irregular substrate surfaces, allowing for tight contact. Spontaneous liquid-to-solid maturation promoted the phase transition of the SF/SDBS complex coacervate to form the SFG hydrogel in situ, enhancing its bulk cohesiveness and interfacial adhesion. The formed SFG hydrogel exhibited intrinsic advantages as a new type of artificial protein-based adhesive, including good biocompatibility, robust wet adhesion, rapid blood-clotting capacity, and easy operation. In vitro and in vivo experiments demonstrated that the SFG hydrogel not only achieved instant and effective hemostatic sealing of tissue injuries but also promoted wound healing and tissue regeneration, thus advancing its clinical applications. STATEMENT OF SIGNIFICANCE: Marine mussels utilize the liquid-liquid phase separation (LLPS) strategy to induce the supramolecular assembly of mussel foot proteins, which plays a critical role in strong underwater adhesion of mussel foot proteins. Herein, an artificial protein-based adhesive hydrogel (named SFG hydrogel) was reported by adopting the LLPS-mediated coacervation of natural protein silk fibroin (SF) and anionic surfactant sodium dodecylbenzene sulfonate (SDBS). The assembled SFG hydrogel enabled the precise spatial positioning and easy self-adjustable deposition on substrate surfaces with irregularities, allowing tight interfacial adhesion and cohesiveness. The SFG hydrogel not only achieved instant and effective hemostatic sealing of tissue injuries but also promoted wound healing and tissue regeneration, exhibiting intrinsic advantages as a new type of artificial protein-based bioadhesives.


Asunto(s)
Fibroínas , Hemostasis , Cicatrización de Heridas , Fibroínas/química , Animales , Hemostasis/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , Hidrogeles/química , Hidrogeles/farmacología , Adhesivos Tisulares/química , Adhesivos Tisulares/farmacología , Ratones , Bencenosulfonatos/química , Humanos , Separación de Fases
4.
Cureus ; 16(2): e55207, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38558632

RESUMEN

Guillain-Barré syndrome (GBS) is a rare acute-onset neurological disease with significant morbidity and mortality. The risk of GBS increases after delivery. Labor and delivery presents many possible risk factors for GBS. However, risk factors and prognosis of postpartum GBS remain unclear due to its low incidence. Here, we first present a patient with a history of postpartum GBS who returned for an elective repeat cesarean section (C-section). For her previous delivery, the patient received spinal anesthesia for an urgent C-section. She presented postpartum with jaw pain, facial palsy, respiratory difficulty, progressive bilateral lower extremity weakness, and areflexia. The diagnosis of GBS was confirmed by cerebrospinal fluid (CSF) examination, nerve conduction studies (NCS), and electromyography (EMG). Her symptoms of GBS improved after intravenous immunoglobulin (IVIG) treatment. The patient also had an Escherichia coli-positive urinary tract infection (UTI), which was treated with nitrofurantoin. For her repeat elective C-section, we performed a dural puncture epidural (DPE) anesthesia. After delivery, she was discharged to home uneventfully. She did not report any new neurological symptoms at her three-week follow-up. Here, we also review published cases of postpartum GBS and discuss peripartum anesthetic considerations for patients with GBS, aiming to inform clinical management of postpartum GBS in the future.

5.
Int J Syst Evol Microbiol ; 63(Pt 10): 3755-3761, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23645022

RESUMEN

A novel nitrogen-fixing strain, designated DQS-4(T), was isolated from oil-contaminated soil in Taiwan and was characterized using a polyphasic taxonomic approach. Cells of strain DQS-4(T) stained Gram-negative, contained poly-ß-hydroxybutyrate granules and were motile rods, surrounded by a thin capsule. Cells displayed a strictly aerobic type of metabolism and fixed nitrogen microaerobically. Growth occurred at 10-45 °C (optimum, 35-40 °C), at pH 7.0-8.0 (optimum, pH 7.0) and with 0-2 % NaCl (optimum, 0.5-1 %). Phylogenetic analyses based on 16S rRNA gene sequences showed that strain DQS-4(T) belonged to the genus Azoarcus, and its closest neighbours were Azoarcus indigens VB32(T) and Azoarcus communis SWub3(T), with sequence similarities of 97.4 and 96.4 %, respectively. The major cellular fatty acids of strain DQS-4(T) were summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0 and C18 : 1ω7c. The major cellular hydroxy fatty acid was C10 : 0 3-OH. The DNA G+C content was 64.5 mol%. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and several uncharacterized aminophospholipids and phospholipids. The mean level of DNA-DNA relatedness between strain DQS-4(T) and A. indigens LMG 9092(T) was 27.4 %. On the basis of the genotypic and phenotypic data, strain DQS-4(T) represents a novel species in the genus Azoarcus, for which the name Azoarcus olearius sp. nov. is proposed. The type strain is DQS-4(T) ( = BCRC 80407(T) = KCTC 23918(T) = LMG 26893(T)).


Asunto(s)
Azoarcus/clasificación , Fijación del Nitrógeno , Contaminación por Petróleo , Filogenia , Microbiología del Suelo , Azoarcus/genética , Azoarcus/aislamiento & purificación , Azoarcus/metabolismo , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/análisis , Hidroxibutiratos/análisis , Datos de Secuencia Molecular , Nitrógeno/metabolismo , Hibridación de Ácido Nucleico , Fosfolípidos/análisis , Poliésteres/análisis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Taiwán
6.
Lifetime Data Anal ; 19(3): 297-316, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23389549

RESUMEN

Cox models with time-varying coefficients offer great flexibility in capturing the temporal dynamics of covariate effects on event times, which could be hidden from a Cox proportional hazards model. Methodology development for varying coefficient Cox models, however, has been largely limited to right censored data; only limited work on interval censored data has been done. In most existing methods for varying coefficient models, analysts need to specify which covariate coefficients are time-varying and which are not at the time of fitting. We propose a dynamic Cox regression model for interval censored data in a Bayesian framework, where the coefficient curves are piecewise constant but the number of pieces and the jump points are covariate specific and estimated from the data. The model automatically determines the extent to which the temporal dynamics is needed for each covariate, resulting in smoother and more stable curve estimates. The posterior computation is carried out via an efficient reversible jump Markov chain Monte Carlo algorithm. Inference of each coefficient is based on an average of models with different number of pieces and jump points. A simulation study with three covariates, each with a coefficient of different degree in temporal dynamics, confirmed that the dynamic model is preferred to the existing time-varying model in terms of model comparison criteria through conditional predictive ordinate. When applied to a dental health data of children with age between 7 and 12 years, the dynamic model reveals that the relative risk of emergence of permanent tooth 24 between children with and without an infected primary predecessor is the highest at around age 7.5, and that it gradually reduces to one after age 11. These findings were not seen from the existing studies with Cox proportional hazards models.


Asunto(s)
Teorema de Bayes , Encuestas de Salud Bucal/estadística & datos numéricos , Modelos de Riesgos Proporcionales , Algoritmos , Bioestadística , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino , Cadenas de Markov , Método de Montecarlo , Análisis de Regresión
7.
Int J Biol Macromol ; 209(Pt A): 680-691, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35413323

RESUMEN

Functionalized two-dimensional Ti3C2Tx (TN-EHL) was prepared as an effective adsorbent for removal of methylene blue dye (MB) and copper ions (Cu2+). Enzymatic hydrolysis lignin (EHL), a reproducible natural resource, was used to functionalize the Ti3C2Tx nanosheets. EHL can not only introduce active functional groups into TN-EHL but also prevent the oxidation of Ti3C2Tx, thus promoting the adsorption performance of TN-EHL. The maximum adsorption capacities of TN-EHL50 (in which the EHL content is 50 wt%) for MB and Cu2+ were 293.7 mg g-1 and 49.96 mg g-1, respectively. The higher correlation coefficients (R2) of MB (0.9996) and Cu2+ (0.9995) indicating that their adsorption processes can be described by the pseudo-second-order kinetic model. The MB adsorption data fit the Freundlich isotherm with R2 of 0.9953, whereas the Cu2+ ions adsorption data fit the Langmuir isotherm with R2 of 0.9998. The thermodynamic analysis indicates that the adsorption process of MB and Cu2+ on TN-EHL50 is spontaneous and endothermic. Significantly, the Cu2+ ions were reduced to Cu2O and CuO particles during the adsorption process. Therefore, TN-EHL has a great potential as an environmentally friendly adsorbent for MB removal and recovery of Cu2+ ions from wastewater.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Cobre , Hidrólisis , Iones , Cinética , Lignina , Azul de Metileno , Titanio , Contaminantes Químicos del Agua/análisis
8.
Int J Pharm ; 355(1-2): 321-7, 2008 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-18242896

RESUMEN

The purpose of the present study was to investigate the effects of particle size on the pharmacokinetics and tissue distribution of oridonin nanosuspensions after intravenous administration. Two oridonin nanosuspensions with markedly different size were prepared by high pressure homogenization method. The particle size of nanosuspension A is 103.3+/-1.5nm, while B is 897.2+/-14.2nm. Dissolution studies showed that complete dissolution could be obtained within 10min for nanosuspension A, however, nanosuspension B showed a slower dissolution, only 85.2% dissolved by 2h. The pharmacokinetics and tissue distribution of oridonin nanosuspensions A and B were studied after intravenous administration using New Zealand rabbits and Kunming mice as experimental animals, respectively. An Oridonin control solution was studied parallelly. The results showed that oridonin nanosuspension A exhibited pharmacokinetic and biodistribution properties similar to solution due to its rapid dissolution in blood circulation. Oridonin nanosuspension B, however, showed a high uptake in RES organs, meanwhile exhibited a markedly different pharmacokinetic property compared to nanosuspension A. These differences could be attributed to the different particle size of the two nanosuspensions considering their zeta potential had no significant difference. In conclusion, particle size showed obvious effects on pharmacokinetics and tissue distribution of nanosuspensions.


Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/farmacocinética , Diterpenos de Tipo Kaurano/administración & dosificación , Diterpenos de Tipo Kaurano/farmacocinética , Animales , Composición de Medicamentos , Excipientes , Inyecciones Intravenosas , Lecitinas , Ratones , Nanopartículas , Tamaño de la Partícula , Poloxámero , Conejos , Solubilidad , Suspensiones , Distribución Tisular
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