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1.
Biomacromolecules ; 25(5): 2965-2972, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38682378

RESUMEN

Nucleic acid therapeutics have attracted recent attention as promising preventative solutions for a broad range of diseases. Nonviral delivery vectors, such as cationic polymers, improve the cellular uptake of nucleic acids without suffering the drawbacks of viral delivery vectors. However, these delivery systems are faced with a major challenge for worldwide deployment, as their poor thermal stability elicits the need for cold chain transportation. Here, we demonstrate a biomaterial strategy to drastically improve the thermal stability of DNA polyplexes. Importantly, we demonstrate long-term room temperature storage with a transfection efficiency maintained for at least 9 months. Additionally, extreme heat shock studies show retained luciferase expression after heat treatment at 70 °C. We therefore provide a proof of concept for a platform biotechnology that could provide long-term room temperature storage for temperature-sensitive nucleic acid therapeutics, eliminating the need for the cold chain, which in turn would reduce the cost of distributing life-saving therapeutics worldwide.


Asunto(s)
ADN , Humanos , ADN/química , Transfección/métodos , Polímeros/química , Respuesta al Choque Térmico/efectos de los fármacos , Temperatura , Calor
2.
Facial Plast Surg ; 40(1): 1-8, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36731512

RESUMEN

The most important factor that distinguishes a youthful appearance from an aged one is the shape of the lower face. This study aimed to examine the outcome of volume reduction of the lower face using laser-assisted liposuction (SmartLipo) at the time of rhytidectomy in Asians. There were 20 patients (Group 1) for whom only extended deep-plane rhytidectomy were performed, while extended deep-plane rhytidectomy with laser-assisted liposuction was performed on 42 patients (Group 2). This study was performed retrospectively. The FACE-Q questionnaire was given to evaluate the subjective result of the patient. Efficacy was evaluated by measuring the fat quantity at the midpoint and anterior border of the masseter muscle on each side by using an ultrasound scan in Group 2. Then, the correlation between the change in the quantity of fat and the FACE-Q was investigated. The overall satisfaction, and satisfaction for the lower face, jawline, and the area under the chin were significantly higher for Group 2 for which the procedure was concurrently performed in comparison to Group 1. In Group 2, change in the fat was reduced by 21.2% (Rt.) and 22.5% (Lt.) at the mid-point and 24.5% (Rt.) and 26.4% (Lt.) at the anterior border of the masseter muscle. Changes in the fat quantity and lower face satisfaction displayed a significant correlation. With a greater reduction in fat quantity, the score of lower face satisfaction was higher. In addition, with a higher level of satisfaction for the lower face and jawline, the overall satisfaction score displayed a higher positive correlation. Laser-assisted liposuction was useful for the additive procedure at the time of rhytidectomy and improved patient's satisfaction after surgery.


Asunto(s)
Lipectomía , Ritidoplastia , Humanos , Ritidoplastia/métodos , Estudios Retrospectivos , Mentón , Rayos Láser , Satisfacción del Paciente
3.
Molecules ; 27(19)2022 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-36235162

RESUMEN

Compared with polymers and nanoparticles, fatty alcohols can not only increase the stability of foam, but also maintain better foamability at pH < 2, which is beneficial to reduce waste liquid and increase decontamination efficiency for radioactive surface pollution. However, different fatty alcohols have different hydrophobic chain lengths. The effects of fatty alcohols with different chain lengths on the performance of decontamination foam were studied at pH < 2, to assist in the selection of suitable fatty alcohols as foam stabilizers. Combined with betaine surfactant and phytic acid, biomass-based foams were synthesized using fatty alcohols with different chain lengths. When the hydrophobic tail groups of the fatty alcohol and the surfactant were the same, the foam showed the best performance, including the lowest surface tension, the highest liquid film strength, the greatest sag-resistance and the best stability. However, when the hydrophobic tail groups were different, the space between adjacent surface active molecules was increased by thermal motion of the excess terminal tail segments (a tail-wagging effect), and the adsorption density reduced on the gas-liquid interface, leading to increased surface tension and decreased liquid film strength, sag-resistance and stability. The use of decontamination foam stabilized by fatty alcohols with the same hydrophobic group as the surfactant was found to increase the decontamination rate of radioactive uranium pollution from 64 to over 90% on a vertical surface.


Asunto(s)
Alcoholes Grasos , Uranio , Betaína , Biomasa , Descontaminación , Alcoholes Grasos/química , Concentración de Iones de Hidrógeno , Ácido Fítico , Polímeros , Tensoactivos/química
4.
BMC Pediatr ; 20(1): 364, 2020 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-32741368

RESUMEN

BACKGROUND: Evidence of hand, foot, and mouth disease (HFMD) in neonates is limited. The aim of this study was to evaluate the clinical symptoms, pathogens, possible transmission routes, and prognosis of neonatal HFMD in Shanghai. METHODS: This was a case-control study based on the HFMD registry surveillance system. All neonates and infected family members were enrolled between 2016 and 2017 in Shanghai. Neonates with HFMD were followed for at least half a year. Detailed questionnaires, medical history, and physical examination were recorded. Routine blood examination, liver and renal function, immunophenotypes of peripheral blood lymphocytes (CD3, CD4, and CD8 T-cells; NK cells), immunoglobulin (Ig) M, IgG, and IgA, and cytokine interleukin (IL-1ß, IL-2R, IL-6, IL-8, IL-10, and TNF-α) levels were measured. All rectal swab specimens were collected and genotyped for enterovirus, and phylogenetic analysis based on the VP1 sequences of coxsackievirus A6 (CV-A6) was performed to investigate molecular and evolutionary characteristics. T-test or nonparametric test was used to evaluate the differences. Logistic analysis was applied to calculate the risk of clinical manifestations in the group of HFMD neonates and their paired siblings. RESULTS: There were 16 neonates among the 12,608 diagnosed patients with HFMD, accounting for 0.13%. All neonatal infections were transmitted by other members of the family, mainly the elder siblings, and were caused by CV-A6. CV-A6 was the emerging and predominant causative agent of HFMD in Shanghai. None of the neonates with HFMD experienced fever, onychomadesis, or severe complications. However, two elder sibling patients showed lethargy, and one developed hypoperfusion. In the elder siblings with HFMD, the proportion of white blood cells was generally higher than in neonates with HFMD. The immunologic function of the neonates with HFMD was basically normal. The levels of inflammatory markers were higher in both neonates and elder siblings with HFMD compared to age-matched controls. The clinical symptoms receded about 1 week after onset. None of the neonates had sequelae. CONCLUSIONS: In our study, CV-A6 infection in neonates was benign, but had the character of family clustering. Due to the two-child policy in China, elder siblings may be the main route of HFMD transmission.


Asunto(s)
Enterovirus , Enfermedad de Boca, Mano y Pie , Anciano , Estudios de Casos y Controles , Niño , China/epidemiología , Enterovirus/genética , Enfermedad de Boca, Mano y Pie/diagnóstico , Enfermedad de Boca, Mano y Pie/epidemiología , Humanos , Recién Nacido , Filogenia
5.
Phys Chem Chem Phys ; 17(34): 22272-85, 2015 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-26245134

RESUMEN

The waste treatment of polymer materials is often conducted using the photocatalytic technique; however, complete decomposition is frequently inhibited owing to several shortcomings such as low quantum yield and the requirement of ultraviolet irradiation. Herein, we report a strategy to implement moderate management of polymeric films via thermocatalytic oxidative route, which is responsive to heat stimulus. Diverse LDPE-matrix films together with as-prepared thermal catalysts (TCs) or initiators were synthesized to further investigate heat-dependent-catalytic degradation effects. After artificial ageing, structural textures of the as-synthesized films could be chemically deteriorated, followed by a huge increase in surface roughness values, and appreciable loss was also found in the average molecular weights and mechanical parameters. We found an emergent phenomenon in which crystallization closely resembled two-dimensional (2D) growth, which displayed rod-like or disc-type crystal shapes. New chemical groups generated on film surfaces were monitored, and led to a higher limiting oxygen index because of strong catalytic oxidation, thus demonstrating the success of catalytic oxidative ageing by heat actuation. The underlying mechanism responsible for thermocatalytic oxidative pattern is also discussed. Accordingly, these findings may have important implications for better understanding the development of polymeric-matrix waste disposal.


Asunto(s)
Calor , Polietileno/química , Catálisis , Estudios de Factibilidad , Fenómenos Mecánicos , Oxidación-Reducción
6.
Environ Pollut ; 341: 122928, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-37967711

RESUMEN

Natural resistance associated macrophage protein 5 (NRAMP5) is a key transporter for cadmium (Cd) uptake by rice roots; however, the effect of OsNRAMP5 on Cd translocation and redistribution in rice plants remains unknown. In this study, an extremely low Cd-accumulation mutant (lcd1) and wild type (WT) plants were utilized to investigate the effect of OsNRAMP5 mutation on Cd translocation and redistribution via the xylem and phloem and its possible physiological mechanism using field, hydroponic and isotope-labelling experiments. The results showed that OsNRAMP5 mutation reduced xylem and phloem transport of Cd, due to remarkably lower Cd translocation from roots to shoots and from the leaves Ⅰ-Ⅲ to their corresponding nodes, as well as lower Cd concentrations in xylem and phloem sap of lcd1 compared to WT plants. Mutation of OsNRAMP5 reduced Cd translocation from roots to shoots in lcd1 plants by increasing Cd deposition in cellulose of root cell walls and reducing OsHMA2-and OsCCX2-mediated xylem loading of Cd, and the citric acid- and tartaric acid-mediated long-distance xylem transport of Cd. Moreover, OsNRAMP5 mutation inhibited Cd redistribution from flag leaves to nodes and panicles in lcd1 plants by increasing Cd sequestration in cellulose and vacuoles, and decreasing OsLCT1-mediated Cd phloem transport in flag leaves.


Asunto(s)
Cadmio , Oryza , Cadmio/metabolismo , Oryza/genética , Oryza/metabolismo , Floema/metabolismo , Transporte Biológico , Xilema/metabolismo , Mutación , Celulosa/metabolismo , Raíces de Plantas/metabolismo
7.
Chemosphere ; 308(Pt 1): 136187, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36041525

RESUMEN

Accidents involving nuclear leakage and radioactive source diffusion will result in a substantial amount of radioactive pollution, posing a threat to the world's environment as well as human safety. To get rid of the pollution, this work describes a new type of strippable detergent coating designed to remove radioactive contamination, especially in low-temperature conditions. In situ polymerization was employed to make EC/PUA/PVAc detergent from degradable ethyl cellulose (EC), tea polyphenols (TP), and polyvinyl acetate (PVAc), and polytetramethylene ether glycol bis-para-aminobenzoate (P1000). The film-forming performance, decontamination efficiency, and mechanical properties of the decontamination coating formed by the detergent were studied. Designed to work in a low-temperature environment, the detergent can be sprayed and peeled to remove surface radioactive staining. A universal material testing machine was used to assess the low-temperature rheometry, SEM, EDX, FT-IR, and other variables and to characterize the decontamination coating and the decontamination mechanism of the detergent. At -10-10 °C, the EC/PUA/PVAc detergent has good fluidity and sprayability and forms a strippable coating. The tensile strength of the decontamination coating can be as high as 26.4 MPa, and its 180° peel strength on ceramic tile, glass, stainless steel, cement, marble are 0.49 ± 0.08 N/m, 1.82 ± 0.41 N/m, 3.03 ± 1.65 N/m, 35.60 ± 1.17 N/m, 44.43 ± 4.10 N/m, respectively. The decontamination factors ranged from 3.32 to 10.02, with a decontamination rate above 85%.


Asunto(s)
Descontaminación , Acero Inoxidable , Carbonato de Calcio , Detergentes , Éteres , Glicoles , Humanos , Polifenoles , Espectroscopía Infrarroja por Transformada de Fourier , , Temperatura , para-Aminobenzoatos
8.
J Biochem ; 144(6): 781-8, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18845567

RESUMEN

PEGylation of peptide drugs prolongs their circulating lifetimes in plasma. However, PEGylation can produce a decrease in the in vitro bioactivity. Longer poly(ethylene glycol) (PEG) chains are favourable for circulating lifetimes but unfavourable for in vitro bioactivities. In order to circumvent the conflicting effects of PEG length, a hydrophobic peptide, using an antimicrobial peptide as a model, was PEGylated with short PEG chains. The PEGylated peptides self-assembled in aqueous solution into micelles with PEG shell and peptide core. In these micelles, the core peptides were protected by the shell, thus reducing proteolytic degradation. Meanwhile, most of the in vitro antimicrobial activities still remained due to the short PEG chain attached. The stabilities of the PEGylated peptides were much higher than that of the unPEGylated peptides in the presence of chymotrypsin and serum. The antimicrobial activities of the PEGylated peptides in the presence of serum, an ex vivo assay, were much higher than that of the unPEGylated peptide.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/química , Polietilenglicoles/química , Dicroismo Circular , Portadores de Fármacos/química , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía Electrónica de Transmisión , Peso Molecular
9.
Carbohydr Polym ; 162: 62-70, 2017 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-28224896

RESUMEN

Carboxylmethyl konjac glucomannan conjugated polydopamine (CMKGM-PDA) composite was successfully prepared using a cost-effective method. CMKGM-PDA exhibited excellent adsorption performance for the removal of Pb(II) and could be a convenient agent for recovery. The Langmuir linear model was suitable for describing the adsorption process of Pb(II). The maximum adsorption capacity was 95.24mgg-1 at 298K, showing a high absorption capacity in comparison to similar absorbents. The pseudo-second order equation and intra-particle diffusion model exhibited good correlation with the adsorption kinetic. The thermodynamic values (ΔH0 > 0, ΔS0 > 0, ΔG0 < 0) indicated that the adsorption process of Pb(II) was endothermic, feasible, and spontaneous in nature. The chelation and electrostatic attraction between Pb(II) and -OH (or -NH2) groups on the CMKGM-PDA formed a possible adsorption mechanism.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Indoles/química , Plomo/aislamiento & purificación , Mananos/química , Polímeros/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Cinética , Termodinámica
10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 23(4): 822-5, 2006 Aug.
Artículo en Zh | MEDLINE | ID: mdl-17002116

RESUMEN

Membranes prepared from bovine skin collagen were exposed to 15, 25, 35 KGy gamma-radiation respectively at low temperature. Radiation dose rate of about 22 KGy/h was used. The stability of the membranes was evaluated by measuring resistance of collagen membranes to collagenase digestion. Infrared spectra analyses of collagen films were performed in order to explore possible mechanisms of irradiation modification of collagen membranes. The results revealed that the degree of cross-linking and stability of collagen membranes after gamma-irradiation were improved. The MTT assay and SEM observation of the morphology of L929 mouse fibroblast cells which directly cultured on the collagen membranes were employed to evaluate the cytocompatibility of collagen membranes treated by gamma-ray radiation. In the range of 0 to approximately 25 KGy irradiation dose, no significant difference in cytocompatibility of collagen membranes irradiated by gamma-ray was observed. However, when the irradiation dose was over 25 KGy, the cytocompatibility of collagen membranes was influenced by gamma-radiation to some degree.


Asunto(s)
Colágeno/efectos de la radiación , Rayos gamma , Animales , Bovinos , Relación Dosis-Respuesta en la Radiación , Técnicas In Vitro , Ensayo de Materiales , Membranas Artificiales , Ratones
11.
J Bone Miner Res ; 31(11): 1979-1987, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27291868

RESUMEN

Osteopetrosis (OMIM: 611497), literally "stone bone," is a group of inherited bone disorders characterized by increased skeletal mass due to defective osteoclast function. A patient who reported a history of frequent fractures, weakness and fatigue was admitted to our hospital in 2011. The patient presented with the typical features of osteopetrosis: fractures after minor trauma, early tooth loss, anemia, hepatosplenomegaly, and a generalized increase in bone mineral density (BMD). Aside from his father's complaint of excessive tooth loss, his mother, two sisters, son, and daughter were healthy. Blood samples of the family members were drawn for genetic analyses. The entire coding region and adjacent splice sites of the pleckstrin homology domain-containing family M (with RUN domain) member 1 (PLEKHM1) gene were sequenced. One mutation, a heterozygous deletion mutation in exon 11 (c.3051_3052delCA), was identified in the patient but not in his relatives. The mutation leads to a translation product with a highly impaired Rubicon homology domain. Co-immunoprecipitation and immunofluorescence analyses using HEK293 cells showed that overexpression of a PLEKHM1 CA-deletion mutant resulted in a dramatic decrease in the interaction between PLEKHM1 and the small GTPase Rab7 compared to wild-type PLEKHM1. The normal processes of endocytosis and autophagy were disturbed in cells expressing the mutant (transfected HEK293 and U937 cells), as indicated by epidermal growth factor receptor (EGFR) degradation and an altered LC3-I/II ratio, respectively, which may lead to a defect in osteoclast function. A four-year follow-up study of the patient showed that the PLEKHM1-dependent osteopetrosis was relatively malignant, with significant symptoms of pancytopenia and hepatosplenomegaly. © 2016 American Society for Bone and Mineral Research.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Predisposición Genética a la Enfermedad , Glicoproteínas de Membrana/genética , Mutación/genética , Osteopetrosis/genética , Osteopetrosis/patología , Autofagia , Proteínas Relacionadas con la Autofagia , Secuencia de Bases , Análisis Mutacional de ADN , Endocitosis , Estudios de Seguimiento , Células HEK293 , Humanos , Masculino , Persona de Mediana Edad , Osteopetrosis/diagnóstico por imagen , Unión Proteica , Proteínas de Unión al GTP rab/metabolismo , Proteínas de Unión a GTP rab7
12.
J Chromatogr A ; 1476: 46-52, 2016 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-27865455

RESUMEN

Ustiloxins are cyclopeptide mycotoxins produced by the pathogenic fungus Ustilaginoidea virens of rice false smut. Quantification of ustiloxins is essential to assess the food safety of rice infected by rice false smut disease. This paper describes a sensitive method for the simultaneous quantification of ustiloxins A, B, C, D and F in rice grains using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Since notable matrix enhancement effects (21%-78%) occurred for all of the target analytes (except for ustiloxin A), several solid phase extraction materials were tested for their ability to retain ustiloxins from aqueous solutions prior to the LC-MS/MS analysis, including C18 sorbents, polymer anion exchange sorbents resin (PAX), and polymer cation exchange resin (PCX). The PCX resin was adopted due to its higher extraction capability and selectivity for all targets compared to others, and in this case, almost no matrix effects (-5% to 8%) were observed for all of the ustiloxins monitored. The developed method reached limits of quantification of 0.2-2ngg-1, and linearity was statistically verified over two orders of magnitude with regression coefficients (R2)>0.991. The mean recoveries were from 85% to 109%, and the inter-day precisions (n=11) were less than 16%, with intra-day precisions (n=6) within 12%. Analysis of samples showed that ustiloxin A was the dominant species, with the content ranging from 5.5 to 273.8ngg-1, followed by ustiloxin B (≤88.7ngg-1), while concentrations of ustiloxins C, D and F were slightly lower (≤43.2ngg-1). To our knowledge, this is the first report on the determination and analysis of five ustiloxins simultaneously in a single analysis.


Asunto(s)
Resinas de Intercambio de Catión , Cromatografía Líquida de Alta Presión , Micotoxinas/análisis , Oryza/microbiología , Péptidos Cíclicos/análisis , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem , Hypocreales/química , Micotoxinas/química , Micotoxinas/aislamiento & purificación , Péptidos Cíclicos/química , Péptidos Cíclicos/aislamiento & purificación , Polímeros
14.
Carbohydr Polym ; 90(4): 1595-600, 2012 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-22944421

RESUMEN

The blend films of ungelatinized and gelatinized starch/polyvinyl alcohol (PVA) were prepared with a solution casting method by the introduction of additives (glycerol/urea) or not. The phase morphologies and thermal behaviors of the blends were carefully analyzed. A droplet phase was observed in the blends containing ungelatinized starch and a laminated phase was observed in the blends containing gelatinized starch. For both ungelatinized and gelatinized starch/PVA blends, the melting temperature (T(m)) (210-230 °C) of PVA was detected, and the T(m) of gelatinized starch/PVA blends was higher than that of the ungelatinized starch/PVA blends. Blend films containing 16.8 wt% of glycerol or urea exhibited a decreased T(m). The introduction of additives (glycerol or urea) reduced the decomposition onset temperature of the blend films. These various morphologies and thermal behaviors could be attributed to the different hydrogen bonding interaction characteristics between starch and polyvinyl alcohol at different conditions.


Asunto(s)
Materiales Biocompatibles/química , Gelatina/química , Glicerol/química , Alcohol Polivinílico/química , Solventes/química , Almidón/química , Urea/química , Rastreo Diferencial de Calorimetría , Glicerol/farmacología , Enlace de Hidrógeno , Microscopía Electrónica de Rastreo , Solventes/farmacología , Temperatura , Termogravimetría , Urea/farmacología , Zea mays
15.
J Hazard Mater ; 171(1-3): 802-8, 2009 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-19604636

RESUMEN

Carboxylic acid functionalized deacetylated konjac glucomannan was synthesized by free radical graft copolymerization of methyl acrylate (MA) and methyl methacrylate (MMA) onto the backbone of deacetylated konjac glucomannan with subsequent chemical activation of the ester groups in the side chains of the resulting graft copolymer by sodium hydroxide. Effects of sodium hydroxide concentration and hydrolyzed time on the conversion of ester groups into carboxylic acid groups were studied. A comprehensive adsorption study of Cu(2+) and Pb(2+) ions from aqueous solution was also conducted regarding the effects of initial pH, adsorbent dosage, time, and initial concentration. The new konjac glucomannan adsorbent offered high removal efficiency, fast adsorption rate and high uptake capacity for Cu(2+) and Pb(2+) ions. The maximum removal efficiency at pH 5.0 was found to 98% for Cu(2+) and 99% for Pb(2+) ions. The kinetic data were fitted well to pseudo-second-order model. The maximum uptake capacity of Cu(2+) and Pb(2+) ions onto carboxylic acid functionalized deacetylated konjac glucomannan was found to 64.5 mg g(-1) and 191.3 mg g(-1), respectively. The isotherm adsorption data was well described by the Langmuir isotherm model.


Asunto(s)
Ácidos Carboxílicos/química , Cobre/aislamiento & purificación , Plomo/aislamiento & purificación , Mananos/química , Acrilatos/química , Adsorción , Carbón Mineral , Cobre/análisis , Cobre/química , Concentración de Iones de Hidrógeno , Iones , Cinética , Plomo/análisis , Plomo/química , Metilmetacrilatos/química , Modelos Químicos , Hidróxido de Sodio/química , Factores de Tiempo
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