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1.
J Oral Rehabil ; 51(9): 1675-1683, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38926933

RESUMEN

BACKGROUND: The T-scan system has been used previously to analyse occlusion, but the quantitative analysis of occlusal contact by T-Scan system has yet to be reported. OBJECTIVES: To evaluate the reliability and validity of T-Scan system for quantitatively measuring occlusal contact area and occlusal contact number. METHODS: Twenty-two individuals with normal occlusion, 11 men and 11 women, were recruited for the study. Two occlusal analysis methods, including silicone transmission analysis method (STA) and T-Scan occlusion analysis method (TSO), were used to make quantitative analysis to measure occlusal contact area (OCA) and occlusal contact number (OCN). A test-retest check was performed with an interval of 2 weeks. The values of intraclass correlation coefficients (ICC) between test-retest of each method were calculated for reliability evaluation. Pearson correlations analysis, paired t-tests, regression analysis and Bland-Altman analysis were performed for validity evaluation. RESULTS: The ICC values of STA were greater than those of TSO for OCA while for OCN, ICC values of TSO were greater than STA. The higher OCA and OCN values were found in TSO compared with STA. Pearson's correlation coefficient indicated strong relations between TSO and STA (0.730-0.812) for OCA, while good relations between then (0.569-0.583) for OCN. Paired t-test showed a significant difference between the OCA and OCN values between TSO and STA. Bland-Altman analysis showed good agreement between OCA and OCN values of TSO and STA both in men and women. Regression analysis identified a linear correlation between OCA values obtained from these two methods. CONCLUSIONS: T-Scan method showed strong reliability for measuring OCA and OCN quantitatively. Strong correlations were found between OCA values from TSO and STA method, but the validity of TSO for measuring OCN needs to be promoted. CLINICAL SIGNIFICANCE: T-Scan system demonstrates good potential in quantitative analysis of occlusion, which will expand its clinical application.


Asunto(s)
Oclusión Dental , Humanos , Femenino , Masculino , Reproducibilidad de los Resultados , Adulto , Adulto Joven , Registro de la Relación Maxilomandibular/métodos , Registro de la Relación Maxilomandibular/instrumentación
2.
Anal Chem ; 95(16): 6690-6699, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-36961950

RESUMEN

Fully integrated wearable sensors are capable of dynamically, directly, and independently tracking biomarkers in raw noninvasive biofluids without any other equipment or accessories by integrating the unique on-body monitoring feature with the special complete functional implementation attribute. Sweat, saliva, and urine are three important noninvasive biofluids, and changes in their biomarkers hold great potential for revealing physiological conditions. However, it is still a challenge to design single fully integrated wearable sensor arrays (FIWSAs) that are universally able to concurrently measure electrolytes and metabolites in three of the most common noninvasive biofluids including sweat, saliva, and urine. Here, we propose the first single universal FIWSAs for wirelessly, noninvasively, and simultaneously measuring various metabolites (i.e., uric acid) and electrolytes (i.e., Na+ and H+) in raw sweat, saliva, or urine under subjects' exercise by integrating the specifically designed microfluidic, sensing, and electronic modules in a seamless manner. We evaluate its utility for noninvasive gout management in healthy subjects and in gout patients through a purine-rich meal challenge and with a medicine-treatment control, respectively. Noninvasive monitoring of multiple electrolytes and metabolites in a variety of raw noninvasive biofluids via such single universal FIWSAs may enrich the understanding of the biomarkers' levels in the body and would also facilitate self-health management.


Asunto(s)
Técnicas Biosensibles , Gota , Dispositivos Electrónicos Vestibles , Humanos , Sudor , Saliva , Monitoreo Fisiológico , Electrólitos , Biomarcadores
3.
Nat Chem Biol ; 17(1): 89-95, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32989299

RESUMEN

TRAAK is an ion channel from the two-pore domain potassium (K2P) channel family with roles in maintaining the resting membrane potential and fast action potential conduction. Regulated by a wide range of physical and chemical stimuli, the affinity and selectivity of K2P4.1 toward lipids remains poorly understood. Here we show the two isoforms of K2P4.1 have distinct binding preferences for lipids dependent on acyl chain length and position on the glycerol backbone. The channel can also discriminate the fatty acid linkage at the SN1 position. Of the 33 lipids interrogated using native mass spectrometry, phosphatidic acid had the lowest equilibrium dissociation constants for both isoforms of K2P4.1. Liposome potassium flux assays with K2P4.1 reconstituted in defined lipid environments show that those containing phosphatidic acid activate the channel in a dose-dependent fashion. Our results begin to define the molecular requirements for the specific binding of lipids to K2P4.1.


Asunto(s)
Ácidos Fosfatidicos/química , Canales de Potasio/química , Potasio/química , Adenosina/análogos & derivados , Adenosina/química , Adenosina/metabolismo , Cationes Monovalentes , Clonación Molecular , Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Glicerofosfolípidos/química , Glicerofosfolípidos/metabolismo , Humanos , Activación del Canal Iónico , Transporte Iónico , Cinética , Liposomas/química , Liposomas/metabolismo , Ácidos Fosfatidicos/metabolismo , Fosfatidilcolinas/química , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/metabolismo , Fosfatidilgliceroles/química , Fosfatidilgliceroles/metabolismo , Fosfatidilserinas/química , Fosfatidilserinas/metabolismo , Pichia/genética , Pichia/metabolismo , Potasio/metabolismo , Canales de Potasio/genética , Canales de Potasio/metabolismo , Unión Proteica , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
4.
BMC Oral Health ; 23(1): 190, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-37005643

RESUMEN

BACKGROUND: Occlusal analysis is essential in the dental clinical practice. However, the traditional occlusal analysis performed on the two-dimensional level can not directly correspond to the tooth surface with three-dimensional profile, therefore the clinical guidance value is limited. METHODS: By combining the 3D digital dental models and quantitative data from 2D occlusal contact analysis, this study constructed a novel digital occlusal analysis method. The validity and reliability of DP and SA were verified by comparing the results of occlusal analysis of 22 participants. ICC values for occlusal contact area (OCA) and occlusal contact number (OCN) were tested. RESULTS: Results confirmed the reliability of the two occlusal analysis methods with ICC values of 0.909 for SAOCA, 0.906 for DPOCA, 0.929 for SAOCN and 0.904 for DPOCN. The Bland-Altman plot, paired t-test (tOCN = 0.691, P > 0.05) and Pearson correlation analysis results (R = 0.68, p < 0.001) verified the validity between SA and DP. Then a novel digital occlusal analysis method was constructed, which not only can locate the occlusion contact and provide the quantitative analysis, but also provide a comprehensive description of the resultant force of each tooth and the component forces on the x-, y- and z-axis. CONCLUSIONS: This new occlusal analysis method can obtain quantitative analysis of occlusal contact including contact area and force information simultaneously, which will provide new impetus and greater help for clinical dental treatment and scientific research.


Asunto(s)
Oclusión Dental , Imagenología Tridimensional , Humanos , Reproducibilidad de los Resultados , Modelos Dentales
5.
Anal Chem ; 94(3): 1890-1900, 2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35006672

RESUMEN

By combining the distinctive noninvasive feature with the peculiar complete functional implementation trait, fully integrated raw noninvasive biofluid glucose biosensors offer active and remote glucose monitoring while posing minimal harm or infection risks compared to the traditional invasive manner. However, each previously reported fully integrated raw noninvasive biofluid glucose biosensor is solely focused on single-type raw noninvasive biofluid analysis. Given the diversity and complexity of subjects' physical conditions, single-type raw noninvasive biofluids are inappropriate to all crowds (e.g., sweat collection/analysis could be inapplicable for dermatopathic subjects). Here, we demonstrate the first example of a universal fully integrated nanoelectronic system with the unique capability to point-of-care and universally monitor diverse raw noninvasive biofluid (i.e., sweat, tears, and saliva) glucose by combining a flexible and disposable microfluidic enzymatic biosensor (named iezSlice) for raw biofluid pump-free sampling and measurement with a customized, handheld, and reusable wireless electronic device (named iezBar) for electrical signal transduction, conditioning, processing, and wireless transmission. We employed the specially designed high-concentration-buffer powder-loaded Kimwipes (HBP-KWs) as the microfluidic channel (microchannel) of iezSlice, guaranteeing a high-accuracy glucose analysis in various raw noninvasive biofluids. We also evaluated the potential utility of the universal fully integrated nanoelectronic system for noninvasive glucose management in healthy and diabetic subjects with the assistance of the proposed volatility-derived blood glucose concentration-free protocol. Although we focus on raw noninvasive biofluid glucose analysis in this work, the universal fully integrated nanoelectronic system may readily realize accurate monitoring of various biomolecules in raw noninvasive biofluids by introducing corresponding bioreceptors.


Asunto(s)
Técnicas Biosensibles , Glucemia , Técnicas Biosensibles/métodos , Automonitorización de la Glucosa Sanguínea , Glucosa , Humanos , Microfluídica , Sistemas de Atención de Punto , Saliva , Sudor
6.
Anal Chem ; 93(2): 769-776, 2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33320532

RESUMEN

Highly toxic chlorine gas imposes serious health risks in the workplace. The ability to on-site, real-time monitoring of instantaneous and time-weighted average (TWA) chlorine gas concentrations in a simple, sensitive, accurate, and reliable manner would be highly beneficial to improve workplace health and safety. Here, we propose and experimentally validate a gaseous chlorine detection principle based on a N,N-diethyl-p-phenylenediamine sulfate salt/Cl2 colorimetric reaction-controlled membrane process to regulate the gaseous chlorine transport across a gas-permeable membrane that enables the establishment of a time-resolved analytical relationship to quantify chlorine concentration by multidata points with dramatically enhanced accuracy and reliability. A gas-permeable membrane-based portable colorimetric gaseous chlorine sensing probe (MCSP) was designed and fabricated. The MCSP embedded the proposed analytical principle that is capable of real-time continuous monitoring of the instantaneous and TWA chlorine gas concentrations within an analytical range of 0.009-2.058 mg L-1 without the need for on-going calibration, which could be a useful analytical tool for managing the toxic chlorine gas-imposed health risks in workplaces.


Asunto(s)
Cloro/química , Colorimetría/instrumentación , Colorimetría/métodos , Membranas Artificiales , Monitoreo del Ambiente , Humanos , Exposición Profesional , Reproducibilidad de los Resultados
7.
Neuroimmunomodulation ; 28(3): 158-165, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34237753

RESUMEN

INTRODUCTION: This study investigated the clinical values of miR-27a-3p for pulpitis patients, and its association with TLR4. METHODS: Sixty-six patients with pulpitis and 34 cases without pulpitis were recruited; the pulp tissue and serum samples were collected from each participant. Real-time polymerase chain reaction was used for measurement of gene expression levels. The diagnosis values were assessed by the receiver operating characteristic curve. The target gene of miR-27a-3p was confirmed by the luciferase reporter assay. RESULTS: MiR-27a-3p was downregulated in both serum and pulp tissue of pulpitis patients. MiR-27a-3p could distinguish pulpitis patients from healthy controls and might be a predictor for the development of irreversible pulpitis. A high level of TLR4 was also detected in both peripheral blood monocytes and pulp tissues from pulpitis patients and showed a negative association with the miR-27a-3p level. TLR4 was a direct target gene of miR-27a-3p. DISCUSSION/CONCLUSION: MiR-27a-3p might be a promising biomarker for the diagnosis of pulpitis and predict the development of irreversible pulpitis. MiR-27a-3p might be involved in the pathogenesis of pulpitis via targeting TLR4.


Asunto(s)
MicroARNs , Pulpitis , Expresión Génica , Humanos , MicroARNs/genética , Pulpitis/diagnóstico , Pulpitis/genética
8.
Plant Dis ; 105(4): 889-895, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33044138

RESUMEN

Phenamacril is a cyanoacrylate fungicide that provides excellent control of Fusarium head blight (FHB) or wheat scab, which is caused predominantly by Fusarium graminearum and F. asiaticum. Previous studies revealed that codon mutations of the myosin-5 gene of Fusarium spp. conferred resistance to phenamacril in in vitro lab experiments. In this study, PCR restriction fragment length polymorphism (RFLP) was developed to detect three common mutations (A135T, GCC to ACC at codon 135; S217L, TCA to TTA at codon 217; and E420K, GAA to AAA at codon 420) in F. graminearum induced by fungicide domestication in vitro. PCR products of 841 bp (for mutation of A135T), 802 bp (for mutation of S217L), or 1,649 bp (for mutation of E420K) in the myosin-5 gene were amplified by appropriate primer pairs. Restriction enzyme KpnI, TasI, or DraI was used to distinguish phenamacril-sensitive and -resistant strains with mutation genotypes of A135T, S217L, and E420K, respectively. KpnI digested the 841-bp PCR products of phenamacril-resistant strains with codon mutation A135T into two fragments of 256 and 585 bp. In contrast, KpnI did not digest the PCR products of sensitive strains. TasI digested the 802-bp PCR products of phenamacril-resistant strains with codon mutation S217L into three fragments of 461, 287, and 54 bp. In contrast, TasI digestion of the 802-bp PCR products of phenamacril-sensitive strains resulted in only two fragments of 515 and 287 bp. DraI digested the 1,649-bp PCR products of phenamacril-resistant strains with codon mutation E420K into two fragments of 932 and 717 bp, while the PCR products of phenamacril-sensitive strains was not digested. The three genotypes of resistance mutations were determined by analyzing electrophoresis patterns of the digestion fragments of PCR products. The PCR-RFLP method was evaluated on 48 phenamacril-resistant strains induced by fungicide domestication in vitro and compared with the conventional method (mycelial growth on fungicide-amended agar). The accuracy of the PCR-RFLP method for detecting the three mutation genotypes of F. graminearum resistant to phenamacril was 95.12% compared with conventional method. Bioinformatics analysis revealed that the PCR-RFLP method could also be used to detect the codon mutations of A135T and E420K in F. asiaticum.


Asunto(s)
Fusarium , Cianoacrilatos , Fusarium/genética , Genotipo , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción
9.
Ecotoxicol Environ Saf ; 190: 110151, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31923754

RESUMEN

Potentially toxic metals (PTMs), associated with different size particles in soil, may play an important role in adverse health effect and risk for human. The objective is to evaluate the lung and gastrointestinal bioaccessibility and risk of PTMs in Pb-contaminated alkaline urban soil depending on the particle size fractions. The size fractions of 50-250 µm, 5-50 µm, 1-5 µm, <1 µm in Pb-contaminated alkaline urban soil from Baoji Heavy Industrial Base City, NW China, were screened by Sequential Wet Sieving Separation Procedure (SWSSP) based on Stokes' Law. The concentrations of 9 potentially toxic metals (As, Ba, Co, Cr, Cu, Mn, Ni, Pb and Zn) in each particle size fractions were characterized by ICP-OES and ICP-MS, and the in vitro bioaccessibility dependent of size fractions were evaluated by the simulation fluids of Artificial Lysosomal Fluid (ALF) and Gamble for lung, PBET, SBET, IVG, SBRC, UBM for gastric and intestinal, respectively. Health risks were assessed considering simulated external exposure using intestinal and lung bioaccessibility. The lung and gastrointestinal bioaccessibility and exposure risks of PTMs in fine particle size (i.e. <1 µm) was higher than larger particle size fractions (i.e. 50-250 µm, 5-50 µm, 1-5 µm), however, some different variations of bioaccessibility observed the simulation fluids and time dependent. In case of single PTMs, the lung bioaccessibilities of PTMs in ALF were higher than those in Gamble fluids, most prominent in Co, Cu, Mn and Zn, while the gastrointestinal [G + I] bioaccessibility of PTMs was less than those in gastric [G], like Cu, Mn, Pb and Zn mostly. The non-carcinogenic risks of these PTMs to children via inhalation were acceptable and higher than those of adults, but reverse for carcinogenic risk. Comparatively, the non-carcinogenic and carcinogenic risks of PTMs via ingestion pathway were both higher than those for adults. Although the risks from ingestion were in acceptable range, the total carcinogenic risks for children were more than 10-4, which would bring carcinogenic risks and should be paid attention to. It was noted that the toxic metal, Co in all size fractions was the most important contributor for noncarcinogenic risks and Cr mostly for carcinogenic risks via inhalation pathway for adults and children in local areas. However, Pb was the most important contributor for noncarcinogenic risk both for adults and children via ingestion pathway relative to Co and Cr for carcinogenic risks through hand-to-mouth ingestion. Those observations demonstrated the important role that the smaller particle fractionations in Pb-contaminated alkaline soil played in both bioaccessibility and the refinement of human health-risk assessments for the inhalation and ingestion pathway.


Asunto(s)
Arsénico/metabolismo , Tracto Gastrointestinal/metabolismo , Pulmón/metabolismo , Metales Pesados/metabolismo , Tamaño de la Partícula , Contaminantes del Suelo/metabolismo , Adulto , Arsénico/química , Disponibilidad Biológica , Niño , China , Ciudades , Humanos , Metales Pesados/química , Modelos Biológicos , Medición de Riesgo/métodos , Contaminantes del Suelo/química
10.
Langmuir ; 35(7): 2480-2489, 2019 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-30673289

RESUMEN

The design of topographically patterned surfaces is considered to be a preferable approach for influencing cellular behavior in a controllable manner, in particular to improve the osteogenic ability of bone regeneration. In this study, we fabricated nanolamellar tantalum (Ta) surfaces with lamellar wall thicknesses of 40 and 70 nm. The cells attached to nanolamellar Ta surfaces exhibited higher protein adsorption and expression of ß1 integrin, as compared to the nonstructured bulk Ta, which facilitated the initial cell attachment and spreading. We thus, as expected, observed significantly enhanced osteoblast adhesion, growth, and alkaline phosphatase activity on nanolamellar Ta surfaces. However, the beneficial effects of nanolamellar structures on osteogenesis became weaker as the lamellar wall thickness increased. The interaction between cells and Ta surfaces was examined through adhesion forces using atomic force microscopy. Our findings indicated that the Ta surface with a lamellar wall thickness of 40 nm exhibited the strongest stimulatory effect. The observed strongest adhesion force between the cell-attached tip and the Ta surface with a 40 nm thick lamellar wall encouraged the much stronger binding of cells with the surface and thus well-attached, -stretched, and -grown cells. We attributed this to the increase in the available contact area of cells with the thinner nanolamellar Ta surface. The increased contact area allowed the enhancement of the cell surface interaction strength and, thus, improved osteoblast adhesion. This study suggests that the thin nanolamellar topography shows immense potential in improving the clinical performance of dental and orthopedic implants.


Asunto(s)
Materiales Biocompatibles/química , Osteoblastos/metabolismo , Tantalio/química , Adsorción , Fosfatasa Alcalina/metabolismo , Animales , Materiales Biocompatibles/toxicidad , Adhesión Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Integrina beta1/metabolismo , Ratones , Propiedades de Superficie , Tantalio/toxicidad
11.
EMBO Rep ; 17(10): 1422-1430, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27566753

RESUMEN

Iodine antiseptics exhibit superior antimicrobial efficacy and do not cause acquired microbial resistance. However, they are underused in comparison with antibiotics in infection treatments, partly because of their adverse effects such as pain and allergy. The cause of these noxious effects is not fully understood, and no specific molecular targets or mechanisms have been discovered. In this study, we show that iodine antiseptics cause pain and promote allergic contact dermatitis in mouse models, and iodine stimulates a subset of sensory neurons that express TRPA1 and TRPV1 channels. In vivo pharmacological inhibition or genetic ablation of these channels indicates that TRPA1 plays a major role in iodine antiseptics-induced pain and the adjuvant effect of iodine antiseptics on allergic contact dermatitis and that TRPV1 is also involved. We further demonstrate that iodine activates TRPA1 through a redox mechanism but has no direct effects on TRPV1. Our study improves the understanding of the adverse effects of iodine antiseptics and suggests a means to minimize their side effects through local inhibition of TRPA1 and TRPV1 channels.


Asunto(s)
Antiinfecciosos Locales/efectos adversos , Hipersensibilidad/etiología , Yodo/efectos adversos , Dolor/etiología , Canales Catiónicos TRPV/genética , Canales de Potencial de Receptor Transitorio/genética , Animales , Línea Celular , Modelos Animales de Enfermedad , Ganglios Espinales/citología , Expresión Génica , Predisposición Genética a la Enfermedad , Humanos , Hipersensibilidad/diagnóstico , Activación del Canal Iónico/efectos de los fármacos , Ratones , Ratones Noqueados , Modelos Biológicos , Mutación , Dolor/diagnóstico , Povidona/efectos adversos , Células Receptoras Sensoriales/efectos de los fármacos , Células Receptoras Sensoriales/metabolismo , Canal Catiónico TRPA1 , Canales Catiónicos TRPV/metabolismo , Canales de Potencial de Receptor Transitorio/metabolismo
12.
J Clin Periodontol ; 45(8): 941-951, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29779210

RESUMEN

AIMS: Long-term oral chronic inflammatory process is closely related to systemic inflammation, which is a main mechanism involved in non-alcoholic fatty liver disease (NAFLD). Tooth loss could reflect the accumulation of oral local inflammation, implying that number of missing teeth may associate with NAFLD. This study evaluated the association between missing teeth and presence of NAFLD in a general population. MATERIALS AND METHODS: A cross-sectional study of 24,470 adults was carried out from the Tianjin Chronic Low-grade Systemic Inflammation and Health Cohort Study. The self-reported number of missing teeth (excluding third molars) was recorded and classified into four categories: 0, 1-2, 3-5, and ≥6. The NAFLD was diagnosed by the liver ultrasonography. Associations were analysed by adjusted multivariable logistic regression. RESULTS: The multivariable-adjusted odds ratios (95% confidence interval) of NAFLD across the categories of missing teeth were as follows: in males, 1.00 (reference), 1.04 (0.93-1.16), 1.06 (0.90-1.24), and 1.40 (1.09-1.81) (p for trend = 0.04); in females, 1.00 (reference), 0.98 (0.83-1.15), 1.11 (0.90-1.37), and 1.07 (0.77-1.48) (p for trend = 0.45). CONCLUSIONS: The number of missing teeth was associated with a higher presence of NAFLD in males but not females.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Pérdida de Diente , Adulto , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Masculino , Oportunidad Relativa
13.
Biomacromolecules ; 17(11): 3508-3515, 2016 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-27700059

RESUMEN

Protein hydrogels are an important class of materials for applications in biotechnology and medicine. The fine-tuning of their sequence, molecular weight, and stereochemistry offers unique opportunities to engineer biofunctionality, biocompatibility, and biodegradability into these materials. Here we report a new family of redox-sensitive protein hydrogels with controllable mechanical properties composed of recombinant silk-elastin-like protein polymers (SELPs). The SELPs were designed and synthesized with different ratios of silk-to-elastin blocks that incorporated periodic cysteine residues. The cysteine-containing SELPs were thermally responsive in solution and rapidly formed hydrogels at body temperature under physiologically relevant, mild oxidative conditions. Upon addition of a low concentration of hydrogen peroxide at 0.05% (w/v), gelation occurred within minutes for the SELPs with a protein concentration of approximately 4% (w/v). The gelation time and mechanical properties of the hydrogels were dependent on the ratio of silk to elastin. These polymer designs also significantly affected redox-sensitive release of a highly polar model drug from the hydrogels in vitro. Furthermore, oxidative gelation was performed at other physiologically relevant temperatures, and this resulted in hydrogels with tunable mechanical properties, thus, providing a secondary level of control over hydrogel stiffness. These newly developed injectable SELP hydrogels with redox-sensitive features and tunable mechanical properties may be potentially useful as biomaterials with broad applications in controlled drug delivery and tissue engineering.


Asunto(s)
Materiales Biocompatibles/química , Sistemas de Liberación de Medicamentos , Elastina/química , Hidrogeles/química , Seda/química , Secuencia de Aminoácidos/genética , Materiales Biocompatibles/uso terapéutico , Elastina/síntesis química , Elastina/uso terapéutico , Hidrogeles/síntesis química , Hidrogeles/uso terapéutico , Fenómenos Mecánicos , Oxidación-Reducción , Polímeros/síntesis química , Polímeros/química , Polímeros/uso terapéutico , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/uso terapéutico , Seda/uso terapéutico , Ingeniería de Tejidos
14.
Langmuir ; 31(13): 3982-92, 2015 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-25782525

RESUMEN

A simple and robust method for one-step synthesis of monodisperse functional polymeric microspheres was established by generation of reversed microemulsion droplets in aqueous phase inside microfluidic chips and controlled evaporation of the organic solvent. Using this method, water-soluble nanomaterials can be easily encapsulated into biodegradable Poly(D,L-lactic-co-glycolic acid) (PLGA) to form functional microspheres. By controlling the flow rate of microemulsion phase, PLGA polymeric microspheres with narrow size distribution and diameters in the range of ∼50-100 µm were obtained. As a demonstration of the versatility of the approach, high-quality fluorescent CdTe:Zn(2+) quantum dots (QDs) of various emission spectra, superparamagnetic Fe3O4 nanoparticles, and water-soluble carbon nanotubes (CNTs) were used to synthesize fluorescent PLGA@QDs, magnetic PLGA@Fe3O4, and PLGA@CNTs polymeric microspheres, respectively. In order to show specific applications, the PLGA@Fe3O4 were modified with polydopamine (PDA), and then the silver nanoparticles grew on the surfaces of the PLGA@Fe3O4@PDA polymeric microspheres by reducting the Ag(+) to Ag(0). The as-prepared PLGA@Fe3O4@PDA-Ag microspheres showed a highly efficient catalytic reduction of the 4-nitrophenol, a highly toxic substance. The monodisperse uniform functional PLGA polymeric microspheres can potentially be critically important for multiple biomedical applications.


Asunto(s)
Microfluídica/métodos , Microesferas , Polímeros/química , Indoles/química , Nanopartículas del Metal/química , Nanotubos de Carbono/química , Puntos Cuánticos , Plata/química
15.
Proc Natl Acad Sci U S A ; 109(28): 11194-9, 2012 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-22733730

RESUMEN

As an adaptation to infrequent access to water, terrestrial mammals produce urine that is hyperosmotic to plasma. To prevent osmotic diuresis by the large quantity of urea generated by protein catabolism, the kidney epithelia contain facilitative urea transporters (UTs) that allow rapid equilibration between the urinary space and the hyperosmotic interstitium. Here we report the first X-ray crystal structure of a mammalian UT, UT-B, at a resolution of 2.36 Å. UT-B is a homotrimer and each protomer contains a urea conduction pore with a narrow selectivity filter. Structural analyses and molecular dynamics simulations showed that the selectivity filter has two urea binding sites separated by an approximately 5.0 kcal/mol energy barrier. Functional studies showed that the rate of urea conduction in UT-B is increased by hypoosmotic stress, and that the site of osmoregulation coincides with the location of the energy barrier.


Asunto(s)
Riñón/metabolismo , Proteínas de Transporte de Membrana/química , Animales , Bovinos , Clonación Molecular , Cristalografía por Rayos X/métodos , Humanos , Ligandos , Liposomas/química , Metabolismo , Modelos Moleculares , Conformación Molecular , Simulación de Dinámica Molecular , Ósmosis , Proteínas/química , Urea/química , Xenopus laevis , Transportadores de Urea
16.
Nanotechnology ; 25(31): 315702, 2014 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-25036467

RESUMEN

Carbon quantum dots (CDs) are promising nanomaterials in biomedical, photocatalytical and photoelectronic applications. However, determining how to explore an ideal precursor for a renewable carbon resource is still an interesting challenge. Here, for the first time, we report that renewable wastes of bagasse as a new precursor were prepared for fluorescent CDs by a hydrothermal carbonization (HTC) process. The characterization results show that such bagasse-derived CDs are monodispersed, contain quasi spherical particles with a diameter of about 1.8 nm and exhibit favorable photoluminescence properties, super-high photostability and good dispersibility in water. Most importantly, bagasse-derived CDs have good biocompatibility and can be easily and quickly internalized by living cancer cells; they can also be used for multicolour biolabeling and bioimaging in cancer cells. It is suggested that bagasse-derived CDs might have potential applications in biomedical and photoelectronic fields.


Asunto(s)
Carbono/química , Celulosa/química , Colorantes Fluorescentes , Puntos Cuánticos/química , Línea Celular Tumoral , Humanos , Microscopía Fluorescente , Neoplasias/patología , Puntos Cuánticos/toxicidad , Puntos Cuánticos/ultraestructura
17.
Adv Mater ; 36(32): e2406007, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38847583

RESUMEN

Natural plant leaves with multiple functions, for example, spectral features, transpiration, photosynthesis, etc., have played a significant role in the ecosystem, and artificial synthesis of plant leaves with multiple functions of natural ones is still a great challenge. Herein, this work presents an aerogel-involved living leaf (AL), most similar to natural ones so far, by embedding super-hydrophobic SiO2 aerogel microparticles in polyvinyl alcohol hydrogel in the presence of hygroscopic salt and chlorophyllin copper sodium to form solid-liquid-vapor triple-state gel. The AL shows a high spectral similarity with all sampled 15 species of natural leaves and exhibits ≈4-7 times transpiration speed higher than natural leaves. More importantly, AL can achieve several times higher photosynthesis than natural leaves without the energy provided by the respiratory action of natural ones. This work demonstrates the feasibility of creating ALs with natural leaf-like triple-state gel structures and multiple functions, opening up new avenues for energy conversion, environmental engineering, and biomimetic applications.


Asunto(s)
Hojas de la Planta , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Geles/química , Dióxido de Silicio/química , Hidrogeles/química , Fotosíntesis , Alcohol Polivinílico/química , Interacciones Hidrofóbicas e Hidrofílicas
18.
Crit Rev Biomed Eng ; 52(2): 27-37, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38305276

RESUMEN

A good tooth cusp extraction is helpful in evaluating the effect of cosmetic dental work in virtual tooth surgery. We propose a new tooth cusp extraction, which integrates the DBSCAN (density-based spatial clustering of applications with noise) clustering algorithm with the neighborhood search algorithm to extract tooth cusp from a three-dimensional cloud-point tooth model. This method used the point cloud height and curvature to screen out the dented point set. Then we employ the DBSCAN clustering algorithm to segment different feature regions of the tooth surface and generate the candidate point set. Finally, the candidate point set was accurately located at the tooth apex through the neighborhood search algorithm and the traversal search method of non-maximum suppression. The experimental results show that the proposed method is superior to the traditional watershed algorithm-based methods by calculating the recall rate and accuracy rate, and also has higher extraction speed and extraction precision than manual extraction methods.


Asunto(s)
Algoritmos , Diente Canino , Extracción Dental , Humanos , Análisis por Conglomerados
19.
Healthcare (Basel) ; 12(17)2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39273712

RESUMEN

BACKGROUND: Food impaction can contribute to a variety of oral health problems. However, the prevalence of food impaction in the population and patient awareness of these issues are poorly reported on. METHODS: A questionnaire about food impaction was designed and uploaded to an online platform (Sojump) which was then circulated among the study participants using various social media platforms. Participants were asked to anonymously respond to the questionnaire regarding the prevalence of food impaction, its influence on their quality of life, their consultation rates and their oral cleaning methods. The survey was conducted through an online survey portal. Statistical analyses were performed using SPSS and GraphPad. The Chi-Square test, Bonferroni test and the Kruskal-Wallis H test were used to measure categorical variables from the survey. RESULTS: The results showed that the prevalence of food impaction in non-dental professional participants was 86.9%. Among these patients, 12,157 pairs/cases of proximal contacts were affected. The number of food impaction cases in posterior teeth was significantly higher than in anterior teeth. Approximately 81.9% of patients believed that food impaction could affect their lives. However, the consultation rate for these patients was only 17.7%. CONCLUSIONS: This study revealed that food impaction continued to have a high rate of incidence and a low rate of consultation, potentially due to a lack of awareness regarding its influence on oral health. To effectively prevent and address problems resulting from food impaction, both dentists and society need to enhance oral health knowledge in the population.

20.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(4): 426-431, 2024 Apr 15.
Artículo en Zh | MEDLINE | ID: mdl-38632061

RESUMEN

Objective: To explore the effectiveness of using antibiotic bone cement-coated plates internal fixation technology as a primary treatment for Gustilo type ⅢB tibiofibular open fractures. Methods: The clinical data of 24 patients with Gustilo type ⅢB tibiofibular open fractures who were admitted between January 2018 and December 2021 and met the selection criteria was retrospectively analyzed. Among them, there were 18 males and 6 females, aged from 25 to 65 years with an average age of 45.8 years. There were 3 cases of proximal tibial fracture, 6 cases of middle tibial fracture, 15 cases of distal tibial fracture, and 21 cases of fibular fracture. The time from injury to emergency surgery ranged from 3 to 12 hours, with an average of 5.3 hours. All patients had soft tissue defects ranging from 10 cm×5 cm to 32 cm×15 cm. The time from injury to skin flap transplantation for wound coverage ranged from 1 to 7 days, with an average of 4.1 days, and the size of skin flap ranged from 10 cm×5 cm to 33 cm×15 cm. Ten patients had bone defects with length of 2-12 cm (mean, 7.1 cm). After emergency debridement, the tibial fracture end was fixed with antibiotic bone cement-coated plates, and the bone defect area was filled with antibiotic bone cement. Within 7 days, the wound was covered with a free flap, and the bone cement was replaced while performing definitive internal fixation of the fracture. In 10 patients with bone defect, all the bone cement was removed and the bone defect area was grafted after 7-32 weeks (mean, 11.8 weeks). The flap survival, wound healing of the affected limb, complications, and bone healing were observed after operation, and the quality of life was evaluated according to the short-form 36 health survey scale (SF-36 scale) [including physical component summary (PCS) and mental component summary (MCS) scores] at 1 month, 6 months after operation, and at last follow-up. Results: All 24 patients were followed up 14-38 months (mean, 21.6 months). All the affected limbs were successfully salvaged and all the transplanted flaps survived. One case had scar hyperplasia in the flap donor site, and 1 case had hypoesthesia (grade S3) of the skin around the scar. There were 2 cases of infection in the recipient area of the leg, one of which was superficial infection after primary flap transplantation and healed after debridement, and the other was sinus formation after secondary bone grafting and was debrided again 3 months later and treated with Ilizarov osteotomy, and healed 8 months later. The bone healing time of the remaining 23 patients ranged from 4 to 9 months, with an average of 6.1 months. The scores of PCS were 44.4±6.5, 68.3±8.3, 80.4±6.9, and the scores of MCS were 59.2±8.2, 79.5±7.8, 90.0±6.6 at 1 month, 6 months after operation, and at last follow-up, respectively. The differences were significant between different time points ( P<0.05). Conclusion: Antibiotic bone cement-coated plates internal fixation can be used in the primary treatment of Gustilo type ⅢB tibiofibular open fractures, and has the advantages of reduce the risk of infection in fracture fixation, reducing complications, and accelerating the functional recovery of patients.


Asunto(s)
Fracturas Abiertas , Traumatismos de los Tejidos Blandos , Fracturas de la Tibia , Masculino , Femenino , Humanos , Persona de Mediana Edad , Tibia/cirugía , Cementos para Huesos , Fracturas Abiertas/cirugía , Antibacterianos , Cicatriz/cirugía , Estudios Retrospectivos , Calidad de Vida , Resultado del Tratamiento , Fracturas de la Tibia/cirugía , Trasplante de Piel , Fijación Interna de Fracturas/efectos adversos , Traumatismos de los Tejidos Blandos/cirugía
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