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1.
J Esthet Restor Dent ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38634200

RESUMEN

OBJECTIVE: This study aimed to present three indicators that represent the proximal contact area gap change under intercuspal occlusion and to see if and how these indicators influence food impaction with tight proximal contact. MATERIALS AND METHODS: Ninety volunteers were recruited for bite force measurement and intraoral scanning. Three-dimensional surface data and buccal bite data were obtained for 60 impacted and 60 non-impacted teeth. The scanning data were imported into the Geomagic Studio 2013 to measure three indicators, which included the gap change maximum (Δdm, µm), the buccolingual position of Δdm (P), and the gap expanded buccolingual range (S, mm). The difference between two groups of three indicators and their relationship with food impaction with tight proximal contact were analyzed by the t test, the Pearson chi-squared test, the nonparametric Mann-Whitney U test, and the binary logistic regression analysis (a = 0.05). RESULTS: All indicators (Δdm, P, and S) were statistically different (p < 0.001, p = 0.002, and p < 0.001) in the impacted and non-impacted groups. Food impaction with tight proximal contact was affected by Δdm and S (p < 0.001, p = 0.039), but not by P (p = 0.409). CONCLUSION: The excessive increase of the gap change maximum and the gap expanded buccolingual range under bite force promoted the occurrence of food impaction with tight proximal contact. CLINICAL SIGNIFICANCE: The use of intraoral scanning to measure the characteristics of the proximal contact area gap change under bite force may help to deepen our understanding of the pathogenesis of food impaction with tight proximal contact. Importantly it can provide a reference basis for individualizing and quantifying occlusal adjustment treatment.

2.
Int J Comput Dent ; 0(0): 0, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-36999665

RESUMEN

AIM: Quantitative dental plaque evaluation is necessary for clinical and scientific work. This study aimed to examine the reliability of this 3D image analysis method by digitally analysing the colour 3D images obtained from an intraoral scanner, and then detecting and quantifying the plaque information and comparing it with the clinical examination results. MATERIALS AND METHODS: A total of 140 teeth from 5 subjects with a standard dentition were enrolled in this study, and plaque examination was performed at two different stages: after 24 hours without oral hygiene (T1) and after habitual brushing (T2). At each time point, the Quigley-Hein plaque index of each tooth surface was recorded separately, followed by colour 3D images obtained using an intraoral scanner, and image analysis and calculation using Geomagic Wrap 2021. RESULTS: It was found that the percentage of plaque staining area calculated from the 3D image analysis correlated well with the plaque index recorded during the clinical examination: the Spearman correlation coefficients were 0.9136 and 0.9061 (p<0.001) for all tooth surfaces at T1 and T2, respectively. The measurements of the three investigators were in good agreement, with intraclass correlation coefficients of 0.989 and 0.992 (P<0.001) for the vestibular and lingual surfaces at T1, and 0.964 and 0.983 (P<0.001) for the vestibular and lingual surfaces at T2. CONCLUSION: In this study, we initially developed a digital 3D evaluation system of dental plaque suitable for research and clinical practice and demonstrated its reliability.

3.
Molecules ; 27(23)2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36500263

RESUMEN

Substituent effects on the ultraviolet absorption properties of 2,4-dihydroxy dibenzophenone were investigated experimentally. Nine compounds of 2,4-dihydroxy dibenzophenone with different substituents were prepared by a solvent-free reaction of benzoyl chloride. The maximum absorption wavelength (λmax) of these samples was measured, and their UV resistance properties in cotton fabric as well as in polyester were determined. The results show that the λmax is dependent on the substituents at the benzylidene ring, and both electron donating substituents and electron withdrawing substituents cause a bathochromic shift. The UV resistance of fabric increases with the increase in compound concentration. The dyeing rate of each compound on polyester was higher than that of cotton. On cotton fabric, the dyeing rate of 2,4-dihydroxybenzophenone was the highest, 77.8%. On polyester, that of 2,4-dihydroxy-4'-ethyl dibenzophenone was the highest, 84.1%. The study provides new insights into the effect of substituents on the properties of 2,4-dihydroxy dibenzophenone that are related to the whitening of cotton and polyester materials.


Asunto(s)
Colorantes , Textiles , Solventes , Electrones , Poliésteres
4.
J Med Virol ; 92(12): 3119-3124, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32470169

RESUMEN

Hand, foot, and mouth disease (HFMD) caused by enterovirus 71 (EV71) can lead to high morbidity and mortality, and genetic background plays an important role during the disease process. We investigated the association between the single-nucleotide polymorphism (SNP) rs2564978 of the CD55 gene and susceptibility to and severity of HFMD using the SNPs can multiple SNP typing methods. Soluble CD55 (sCD55) expression was significantly lower in the EV71 HFMD group than in the control group and lower in severe cases than in mild cases (P < .001). Moreover, CD55 rs2564978 (C vs T OR = 1.300, 95% CI, 1.120-1.509) was associated with the risk of EV71 infection, and genotype TC was related to the severity of the infection (TC vs TT OR = 4.523, 95% CI, 2.033-10.066). Our results suggest that sCD55 expression and the CD55 polymorphism rs2564978 may influence the susceptibility to and severity of EV71 infection.

5.
Radiology ; 291(1): 232-238, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30644817

RESUMEN

Purpose To demonstrate the feasibility and safety of using focused ultrasound planning models to determine the treatment parameters needed to deliver volumetric mild hyperthermia for targeted drug delivery without real-time thermometry. Materials and Methods This study was part of the Targeted Doxorubicin, or TARDOX, phase I prospective trial of focused ultrasound-mediated, hyperthermia-triggered drug delivery to solid liver tumors ( ClinicalTrials.gov identifier NCT02181075). Ten participants (age range, 49-68 years; average age, 60 years; four women) were treated from March 2015 to March 2017 by using a clinically approved focused ultrasound system to release doxorubicin from lyso-thermosensitive liposomes. Ultrasonic heating of target tumors (treated volume: 11-73 cm3 [mean ± standard deviation, 50 cm3 ± 26]) was monitored in six participants by using a minimally invasive temperature sensor; four participants were treated without real-time thermometry. For all participants, CT images were used with a patient-specific hyperthermia model to define focused ultrasound treatment plans. Feasibility was assessed by comparing model-prescribed focused ultrasound powers to those implemented for treatment. Safety was assessed by evaluating MR images and biopsy specimens for evidence of thermal ablation and monitoring adverse events. Results The mean difference between predicted and implemented treatment powers was -0.1 W ± 17.7 (n = 10). No evidence of focused ultrasound-related adverse effects, including thermal ablation, was found. Conclusion In this 10-participant study, the authors confirmed the feasibility of using focused ultrasound-mediated hyperthermia planning models to define treatment parameters that safely enabled targeted, noninvasive drug delivery to liver tumors while monitored with B-mode guidance and without real-time thermometry. Published under a CC BY 4.0 license. Online supplemental material is available for this article. See also the editorial by Dickey and Levi-Polyachenko in this issue.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Doxorrubicina/administración & dosificación , Hipertermia Inducida/métodos , Neoplasias Hepáticas/terapia , Terapia por Ultrasonido/métodos , Anciano , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Estudios de Factibilidad , Femenino , Humanos , Liposomas , Masculino , Persona de Mediana Edad , Vehículos Farmacéuticos , Estudios Prospectivos
6.
Lancet Oncol ; 19(8): 1027-1039, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30001990

RESUMEN

BACKGROUND: Previous preclinical research has shown that extracorporeal devices can be used to enhance the delivery and distribution of systemically administered anticancer drugs, resulting in increased intratumoural concentrations. We aimed to assess the safety and feasibility of targeted release and enhanced delivery of doxorubicin to solid tumours from thermosensitive liposomes triggered by mild hyperthermia, induced non-invasively by focused ultrasound. METHODS: We did an open-label, single-centre, phase 1 trial in a single UK hospital. Adult patients (aged ≥18 years) with unresectable and non-ablatable primary or secondary liver tumours of any histological subtype were considered for the study. Patients received a single intravenous infusion (50 mg/m2) of lyso-thermosensitive liposomal doxorubicin (LTLD), followed by extracorporeal focused ultrasound exposure of a single target liver tumour. The trial had two parts: in part I, patients had a real-time thermometry device implanted intratumourally, whereas patients in part II proceeded without thermometry and we used a patient-specific model to predict optimal exposure parameters. We assessed tumour biopsies obtained before and after focused ultrasound exposure for doxorubicin concentration and distribution. The primary endpoint was at least a doubling of total intratumoural doxorubicin concentration in at least half of the patients treated, on an intention-to-treat basis. This study is registered with ClinicalTrials.gov, number NCT02181075, and is now closed to recruitment. FINDINGS: Between March 13, 2015, and March 27, 2017, ten patients were enrolled in the study (six patients in part I and four in part II), and received a dose of LTLD followed by focused ultrasound exposure. The treatment resulted in an average increase of 3·7 times in intratumoural biopsy doxorubicin concentrations, from an estimate of 2·34 µg/g (SD 0·93) immediately after drug infusion to 8·56 µg/g (5·69) after focused ultrasound. Increases of two to ten times were observed in seven (70%) of ten patients, satisfying the primary endpoint. Serious adverse events registered were expected grade 4 transient neutropenia in five patients and prolonged hospital stay due to unexpected grade 1 confusion in one patient. Grade 3-4 adverse events recorded were neutropenia (grade 3 in one patient and grade 4 in five patients), and grade 3 anaemia in one patient. No treatment-related deaths occurred. INTERPRETATION: The combined treatment of LTLD and non-invasive focused ultrasound hyperthermia in this study seemed to be clinically feasible, safe, and able to enhance intratumoural drug delivery, providing targeted chemo-ablative response in human liver tumours that were refractory to standard chemotherapy. FUNDING: Oxford Biomedical Research Centre, National Institute for Health Research.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Doxorrubicina/análogos & derivados , Hipertermia Inducida , Neoplasias Hepáticas/tratamiento farmacológico , Ultrasonografía , Anciano , Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polietilenglicoles/administración & dosificación
7.
Small ; 14(18): e1702170, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29325208

RESUMEN

Flexible and stretchable microscale fluidic devices have a broad range of potential applications, ranging from electronic wearable devices for convenient digital lifestyle to biomedical devices. However, simple ways to achieve stable flexible and stretchable fluidic microchannels with dynamic liquid transport have been challenging because every application for elastomeric microchannels is restricted by their complex fabrication process and limited material selection. Here, a universal strategy for building microfluidic devices that possess exceptionally stable and stretching properties is shown. The devices exhibit superior mechanical deformability, including high strain (967%) and recovery ability, where applications as both strain sensor and pressure-flow regulating device are demonstrated. Various microchannels are combined with organic, inorganic, and metallic materials as stable composite microfluidics. Furthermore, with surface chemical modification these stretchable microfluidic devices can also obtain antifouling property to suit for a broad range of industrial and biomedical applications.


Asunto(s)
Elastómeros/química , Microfluídica/métodos , Dispositivos Electrónicos Vestibles
8.
J Med Virol ; 90(4): 692-698, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29235129

RESUMEN

Hand, foot, and mouth disease (HFMD) caused by enterovirus 71 (EV71) presents with a wide variety of clinical manifestations. Host immune response is a factor that influences disease susceptibility and severity. We investigated the potential association of gene polymorphisms in the pattern recognition receptor (PRR) pathway with the risk and severity of EV71 infection. A total of 180 EV71 HFMD cases (108 severe case; 72 mild cases) were enrolled. A group of 201 sex- and age-matched children was included as a control. All subjects were genotyped for the most common single-nucleotide polymorphisms (SNPs) in the PRR and the PRR signaling pathway using the SNPscan multiple SNP typing method. Binary logistic regression analysis revealed statistically significant differences in polymorphism of RIG-1 between patients and controls (rs3739674 G vs C: OR = 1.502, 95%CI: 1.120-2.014; rs9695310 G vs C: OR = 1.782, 95%CI: 1.312-2.419). Polymorphisms of RIG-1 rs3739674 (G vs C: OR = 2.047, 95%CI: 1.307-3.205) and TLR3 rs5743305 (A vs T: OR = 0.346, 95%CI: 0.212-0.566) were found to be associated with disease severity. The results indicated that RIG-1 (rs3739674 and rs9695310) polymorphisms are associated with an increased risk of EV71-induced HFMD in Chinese children, whereas RIG-1 rs3739674 and TLR3 rs5743305 polymorphisms are associated with disease severity. These findings support an important role of innate immune mechanism in EV71 infection.


Asunto(s)
Enterovirus Humano A/inmunología , Predisposición Genética a la Enfermedad , Enfermedad de Boca, Mano y Pie/genética , Receptores de Reconocimiento de Patrones/genética , Receptores de Ácido Retinoico/genética , Índice de Severidad de la Enfermedad , Transducción de Señal , Pueblo Asiatico , Niño , Preescolar , China , Femenino , Técnicas de Genotipaje , Enfermedad de Boca, Mano y Pie/patología , Humanos , Lactante , Masculino , Polimorfismo de Nucleótido Simple , Medición de Riesgo
9.
Anal Bioanal Chem ; 409(1): 133-141, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27783124

RESUMEN

A fast and ultrasensitive test-strip system combining quantum dots (QDs) with a lateral-flow immunoassay strip (LFIAS) was established for detection of Peste des petits ruminants virus (PPRV) antibody. The highly luminescent water-soluble carboxyl-functionalized QDs were used as the signal output and were conjugated to streptococcal protein G (SPG), which was capable of binding to immunoglobulin G (IgG) from many species through an amide bond to capture the target PPRV IgGs. The PPRV N protein, which was immobilized on the detection zone of the test strip, was expressed by transfecting recombinant Bacmid-PPRV-N with Lipofect into Sf9 insect cells. When exposed to PPRV IgG, QD-SPG bound to PPRV N protein, resulting in the formation of a complex that subsequently produced a bright fluorescent band in response to 365 nm ultraviolet excitation. Sensitivity evaluation showed that the QD-LFIAS limit of detection (LOD) for PPRV antibody was superior to competitive enzyme-linked immunosorbent assay (c-ELISA) and the immunochromatographic strip. No cross reaction was observed when the positive sera of bluetongue virus, canine distemper virus, goat pox virus, and foot-and-mouth disease virus were tested. Further evaluation using field samples indicated that the diagnostic specificity and sensitivity of the QD-LFIAS was 99.47 and 97.67 %, respectively, with excellent agreement between QD-LFIAS and c-ELISA. The simple analysis step and objective results that can be obtained within 15 min indicate that this new method shows great promise for rapid, sensitive detection of PPRV IgG for onsite, point-of-care diagnosis and post vaccination evaluation (PVE). Graphical Abstract Ultrasensitive fluorescent QD immunochromotography in combination with recombinant PPRV N protein could be used to detect PPRV antibody in serum.


Asunto(s)
Anticuerpos Antivirales/sangre , Inmunoensayo/instrumentación , Peste de los Pequeños Rumiantes/sangre , Virus de la Peste de los Pequeños Rumiantes/inmunología , Puntos Cuánticos/química , Tiras Reactivas/análisis , Animales , Anticuerpos Antivirales/inmunología , Diseño de Equipo , Cabras , Límite de Detección , Peste de los Pequeños Rumiantes/inmunología , Virus de la Peste de los Pequeños Rumiantes/aislamiento & purificación , Sistemas de Atención de Punto , Células Sf9
10.
Plant Biotechnol J ; 14(1): 231-9, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25879277

RESUMEN

We describe a novel strategy to produce vaccine antigens using a plant cell-suspension culture system in lieu of the conventional bacterial or animal cell-culture systems. We generated transgenic cell-suspension cultures from Nicotiana benthamiana leaves carrying wild-type or chimeric Bamboo mosaic virus (BaMV) expression constructs encoding the viral protein 1 (VP1) epitope of foot-and-mouth disease virus (FMDV). Antigens accumulated to high levels in BdT38 and BdT19 transgenic cell lines co-expressing silencing suppressor protein P38 or P19. BaMV chimeric virus particles (CVPs) were subsequently purified from the respective cell lines (1.5 and 2.1 mg CVPs/20 g fresh weight of suspended biomass, respectively), and the resulting CVPs displayed VP1 epitope on the surfaces. Guinea pigs vaccinated with purified CVPs produced humoral antibodies. This study represents an important advance in the large-scale production of immunopeptide vaccines in a cost-effective manner using a plant cell-suspension culture system.


Asunto(s)
Quimera/metabolismo , Epítopos/metabolismo , Nicotiana/genética , Células Vegetales/metabolismo , Potexvirus/fisiología , Virión/metabolismo , Animales , Especificidad de Anticuerpos/inmunología , Epítopos/inmunología , Epítopos/ultraestructura , Cobayas , Inmunización , Plantas Modificadas Genéticamente , Recombinación Genética/genética , Suspensiones , Nicotiana/citología , Nicotiana/virología , Virión/ultraestructura
11.
Exp Parasitol ; 166: 68-74, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27004468

RESUMEN

Toxoplasma gondii pathogen is a threat to human health that results in economic burden. Unfortunately, there are very few high-efficiency and low-toxicity drugs for toxoplasmosis in the clinic. (+)-Usnic acid derived from lichen species has been reported to have anti-inflammatory, antibacterial, anti-parasitology, and even anti-cancer activities. Herein, the systematic effect of (+)-usnic acid and (+)-usnic acid-liposome on toxoplasma were studied in vitro and in vivo. The viability of toxoplasma tachyzoite was assayed with trypan blue and Giemsa staining; while the invasive capability of tachyzoite to cardiofibroblasts was detected using Giemsa staining. The survival time of mice and the changes in tachyzoite ultrastructure were studied in vivo. The results showed that (+)-usnic acid inhibited the viability of tachyzoite; pretreatment with (+)-usnic acid significantly decreased the invasion of tachyzoite to cardiofibroblasts in vitro; (+)-usnic acid and (+)-usnic acid-liposome extensively prolonged the survival time of mice about 90.9% and 117%, respectively; and improved the ultrastructural changes of tachyzoite, especially in dense granules, rhoptries, endoplasmic reticulum, mitochondria and other membrane organelles. In summary, these results demonstrate that (+)-usnic acid and (+)-usnic acid-liposome with low toxicity have an inhibitory effect on the viability of toxoplasma tachyzoite, and mainly destructed membrane organelles which are connected with the virulence of toxoplasma. These findings provide the basis for further study and development of usnic acid as a potential agent for treating toxoplasmosis.


Asunto(s)
Antiprotozoarios/farmacología , Benzofuranos/farmacología , Toxoplasma/efectos de los fármacos , Animales , Antiprotozoarios/administración & dosificación , Benzofuranos/administración & dosificación , Células Cultivadas , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/parasitología , Liposomas , Masculino , Ratones , Microscopía Electrónica de Transmisión , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/parasitología , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Toxoplasma/ultraestructura , Toxoplasmosis Animal/tratamiento farmacológico , Usnea/química
12.
Pak J Pharm Sci ; 28(5 Suppl): 1875-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26525018

RESUMEN

Ultrasonic scaling and antibiotic therapy are traditional therapeutic methods for inflammation around the implant but therapeutic effect is not ideal. In view of maintaining flora balance around the implant and implant long-term solid holdup, this experiment observes impact and clinical effect of lactobacillus metabolite on inflammation around the impact to explore a new kind of ecological drug. This drug has little or no side effect, good curative effect and low recurrence rate, which can be applied for broad groups of people. 16 cases with inflammation around the impact were divided into experimental group and control group, 8 cases for each group. Lactobacillus metabolites gargle was offered to experimental group; purified water was offered to control group. Gargle way is 3 times/day, 20 ml/time, 3 min/time and for 7 days. Two groups of cases were clinical and microbiological tested before gargle, 3 days, 7 days and 30 days after gargle. Based on clinical and microbiological test of 8 cases of health implant, we observe sub gingival flora variation trend and clinical effects of infectors with inflammation around implant. Lactobacillus metabolite can improve clinical index of inflammation around the impact including MPLI, GI, MBI and PD. Lactobacillus metabolite has a strong treatment effect on inflammation around the implant and has no side effect.


Asunto(s)
Implantes Dentales/microbiología , Inflamación/prevención & control , Lactobacillus , Adulto , Carga Bacteriana , Implantes Dentales/efectos adversos , Femenino , Encía/microbiología , Humanos , Inflamación/etiología , Inflamación/patología , Masculino , Persona de Mediana Edad , Adulto Joven
13.
J Stomatol Oral Maxillofac Surg ; : 101895, 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38685355

RESUMEN

OBJECTIVE: Bell's palsy, also referred to as clinical manifestations of unilateral facial nerve palsy, encompasses downward angling of the corners of the mouth, the absence of forehead creases, and unilateral incomplete eyelid closure. The incidence of Bell's palsy has increased progressively in recent years, but the underlying mechanism of its occurrence remains unknown; therefore, it is essential to investigate both the cause and treatment of Bell's palsy. Member 2 of the Subfamily V Transient Receptor Potential Cation Channel is a mechanically and thermally sensitive ion channel that plays a crucial role in neural growth and development. Using a novel modeling technique, we endeavored to develop an animal model of Bell's palsy and determine whether TRPV2 expression is altered throughout the course of a facial nerve injury. MATERIALS AND METHODS: The rats were categorized into 3 groups, and their facial nerve function was assessed using RT-qPCR, WB, and pathologic testing, respectively, after undergoing unilateral cold air stimulation for 1, 3, and 7 days. TRPV2 expression was identified using these techniques. RESULTS: In response to cold stimulation, rats exhibited facial nerve paralysis symptoms, demyelinating lesions in the facial nerve, and increased TRPV2 expression. CONCLUSIONS: Extended cold stimulation of the facial nerve in rats may lead to an imbalance in facial nerve homeostasis and increased TRPV2 expression. These findings will contribute to the understanding of the potential mechanism by which cold stimulation affects the facial nerve. Moreover, this finding implies that TRPV2 could possibly function as an additional diagnostic marker or therapeutic target in the context of Bell's palsy.

14.
Nat Commun ; 15(1): 802, 2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38280863

RESUMEN

The skin is intrinsically a cell-membrane-compartmentalized hydrogel with high mechanical strength, potent antimicrobial ability, and robust immunological competence, which provide multiple protective effects to the body. Methods capable of preparing hydrogels that can simultaneously mimic the structure and function of the skin are highly desirable but have been proven to be a challenge. Here, dual structurally and functionally skin-mimicking hydrogels are generated by crosslinking cell-membrane compartments. The crosslinked network is formed via free radical polymerization using olefinic double bond-functionalized extracellular vesicles as a crosslinker. Due to the dissipation of stretching energy mediated by vesicular deformation, the obtained compartment-crosslinked network shows enhanced mechanical strength compared to hydrogels crosslinked by regular divinyl monomers. Biomimetic hydrogels also exhibit specific antibacterial activity and adequate ability to promote the maturation and activation of dendritic cells given the existence of numerous extracellular vesicle-associated bioactive substances. In addition, the versatility of this approach to tune both the structure and function of the resulting hydrogels is demonstrated through introducing a second network by catalyst-free click reaction-mediated crosslinking between alkyne-double-ended polymers and azido-decorated extracellular vesicles. This study provides a platform to develop dual structure- and function-controllable skin-inspired biomaterials.


Asunto(s)
Hidrogeles , Piel , Hidrogeles/química , Materiales Biocompatibles/química , Polímeros , Membrana Celular
15.
Bioresour Technol ; 394: 130268, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38154737

RESUMEN

The complexity of biomass components leads to significant variations in the performance of biomass-based carbon dots (CDs). To shed light on this matter, this study presents a comparative analysis of the fluorescence properties of CDs using pure cellulose, lignin, and protein as models. Three CDs showed different fluorescent properties, resulting from the structure difference and carbonization behavior in the hydrothermal. The relatively gentle thermal degradation of proteins allows the macromolecular structure of amino acids to be preserved. This preservation results in a more regular lattice structure, a larger sp2 domain size, and N-doping, which contribute to the highest quantum yield (QY) of 8.7% of the CDs. In contrast, cellulose undergoes more severe thermal degradation with large amounts of small molecules generated, resulting in the CDs with fewer surface defects, more irregular lattice structures, and lower QY. These results provide a guideline for the design of carbon dots from different biomass.


Asunto(s)
Celulosa , Lignina , Celulosa/química , Carbono/química , Biomasa , Fluorescencia , Colorantes , Colorantes Fluorescentes/química
16.
Environ Sci Technol ; 47(17): 9866-73, 2013 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-23919591

RESUMEN

Molecular diffusion across the sediment-water interface, as one of the key geochemical processes, dictates whether a sediment is a source or sink of chemicals, providing useful data in designing remedial actions. Despite ample previous efforts in quantifying sediment-water diffusion fluxes, the resulting methods are largely unsatisfactory. Herein, we introduce a novel passive sampling device capable of measuring vertical profiles of chemical concentrations near the sediment-water interface, from which diffusion fluxes can be calculated based on a model that we developed. In laboratory testing, diffusion fluxes (0.032-310 ng m(-2) d(-1)) of dichlorodiphenyltrichloroethane and its metabolites obtained from the present sampling device were consistent with those (0.38-610 ng m(-2) d(-1)) determined by using a conventional active sampling method, solid-phase extraction/liquid-liquid extraction. Field deployment of the sampling device yielded individual diffusion fluxes of p,p'-DDD, p,p'-DDE, p,p'-DDMU, o,p'-DDMU, p,p'-DDNU, and p,p'-DBP in the range of 5.9-150 ng m(-2) d(-1), which were comparable to those (5.5-85 ng m(-2) d(-1)) obtained with a benthic chamber. Moreover, diffusion fluxes of p,p'-DDT and o,p'-DDT obtained with the sampling device were negative; i.e., the sediment is acting as a sink for these chemicals, while that could not be found using the benthic chamber. Thus, the passive sampling device can provide better information about the movement of chemicals through the sediment and overlying water for the choice of remedial strategies.


Asunto(s)
Monitoreo del Ambiente/métodos , Agua Dulce/análisis , Sedimentos Geológicos/análisis , Hidrocarburos Clorados/análisis , Extracción Líquido-Líquido/métodos , Extracción en Fase Sólida/métodos , Contaminantes Químicos del Agua/análisis , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Teóricos , Polietileno/química
17.
Huan Jing Ke Xue ; 44(8): 4717-4727, 2023 Aug 08.
Artículo en Zh | MEDLINE | ID: mdl-37694664

RESUMEN

In recent years, China's air environment, water environment, and soil environmental quality have been improved, and a "clear water blue sky" has become a normal state. However, as persistent organic pollutants, endocrine-disrupting chemicals, antibiotics, microplastics, and other emerging contaminants are continuously detected in the environment, these emerging contaminants have gradually been attracting wide attention. Nonylphenol, as a typical endocrine disrupting chemical, has also attracted the attention of researchers. The environmental behaviors and exposure levels of nonylphenol in Chinese water bodies were summarized systematically, and the ecological risks caused by nonylphenol were evaluated based on the risk quotient method and joint probability curve method. The results showed that the toxic effects of nonylphenol on aquatic organisms mainly included acute toxicity, growth and development toxicity, and estrogenic effect and reproductive toxicity. Nonylphenol was commonly found in the water bodies of major drainage areas in China, and the average concentration of nonylphenol ranged from 60 to 1000 ng·L-1, with the highest concentration being as high as 4628 ng·L-1. The results of risk assessment based on the risk quotient method and joint probability curve method showed that nonylphenol had certain risks to aquatic life in the major basins of China. Finally, the commonly used nonylphenol treatment, disposal, and risk management and control technologies were summarized, and the international supervision methods of endocrine-disrupting chemicals were compared. Aiming at addressing the problems existing in China's environmental management, targeted policy suggestions were put forward. The research results can provide reference for the management and control of emerging contaminants in China.


Asunto(s)
Disruptores Endocrinos , Plásticos , Antibacterianos , China , Disruptores Endocrinos/toxicidad , Agua
18.
Environ Sci Pollut Res Int ; 30(49): 107365-107370, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36710310

RESUMEN

Plastic pollution has become a global environmental problem of major concern. However, the plastic contamination in the marine top predators, particularly in endangered species, is incompletely understood because of the limited amount of data on their presence in the digestive system and prey. This study investigated the stomach contents of an endangered but poorly known shark species, the longfin mako shark (Isurus paucus), found in the tropical western Pacific Ocean. We examined the plastics in this female specimen (1.22-m fork length) and her prey to assess the potential for trophic transfer of microplastics. Polypropylene bottle cap and lollipop packaging, longnose lancetfish (Alepisaurus ferox), and squid were found in the stomach of I. paucus, while no apparent internal injuries were noted. The microplastic fragments and granules, confirmed by laser direct infrared spectroscopy, were found in the digestive system of the intact squid ingested by I. paucus, suggesting that trophic transfer may occur between shark and prey. These results indicate that I. paucus is vulnerable to plastic ingestion and provide evidence of trophic transfer of microplastics in shark species. Our study emphasizes the need to evaluate the potential ecotoxicological consequences of increasing plastic pollution to endangered marine top predators.


Asunto(s)
Tiburones , Contaminantes Químicos del Agua , Animales , Femenino , Plásticos , Microplásticos , Océano Pacífico , Peces , Contaminantes Químicos del Agua/análisis , Ingestión de Alimentos , Monitoreo del Ambiente
19.
Adv Mater ; 35(5): e2208157, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36398497

RESUMEN

Chirality is ubiquitous in biological systems, which is closely related to biological functions, life processes, and even the pathogenesis of diseases. However, the interface between the chirality of synthetic materials and organisms, particularly the immune system, remains poorly understood. Here, supramolecular chiral polymer micelles (SCPMs) are prepared by complexing antigenic proteins with chiral amino acid-modified polyethyleneimine. The introduction of chirality not only reduces the toxicity of cationic polymer, but also benefits cell uptake and antigen presentation. Especially, D-chirality presents the lowest cytotoxicity, while promoting the highest expression level of costimulatory molecules on dendritic cells compared to L-chirality and achirality. The superiority of D-chirality to stimulate dendritic cell maturation is supported by immunization with D-SCPMs, which achieves significant antigen-specific proliferation of T cells in the spleen, lymph nodes, and tumor of mice. Chirality-mediated antigen processing and presentation are demonstrated by D-SCPMs self-assembled from chiral alkaline histidine or neutral phenylalanine modified polyethyleneimine and tumor associated ovalbumin or severe acute respiratory syndrome coronavirus 2 spike 1 antigenic protein. Immunoactivation enabled by D-chirality opens a window to prepare potent nanotherapeutics for disease prevention and treatment.


Asunto(s)
COVID-19 , Neoplasias , Animales , Ratones , Presentación de Antígeno , Micelas , Polietileneimina , Antígenos , Polímeros/química
20.
Chemosphere ; 295: 133802, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35149023

RESUMEN

In this comment paper, some critical shortcomings and errors in the original paper [Chemosphere, 290, 133,307] are discussed. The authors have not adhered to the 12 Principles of Green Chemistry by incorporating the highly toxic metal Cd in their ferrite nanocomposite photocatalyst, despite its synthesis being described as green. Neither the necessity nor the effectiveness of Cd addition in relation to catalytic activity were explained. Although adsorption of the substrates on the catalyst is necessary for the photocatalytic process, excessive adsorption may give a false impression of efficient removal as opposed to true degradation or mineralization. This issue is extremely important for experimental design when the solubility of the substances is very low. The authors have disregarded the solvent effect of organic scavengers for the reactive species, potentially attributing a greater contribution of the degradation of substances to hydroxyl radicals. Some suggestions are also provided to improve their work in the field of photocatalysis.


Asunto(s)
Nanocompuestos , Luz Solar , Cadmio , Catálisis , Compuestos Férricos , Cinética , Nanocompuestos/química , Plásticos , Titanio/química
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