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1.
Epidemiol Infect ; 150: e131, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35726737

RESUMEN

Severe fever with thrombocytopenia syndrome (SFTS) virus has caused a large number of human infections since discovered in 2009. This study elucidated epidemiological features and fatal risk factors of SFTS cases accumulated up to ten years in Taizhou, a coastal prefecture of Zhejiang Province in Eastern China. A total of 188 hospitalised SFTS cases (including 40 deaths) reported to Taizhou Center for Disease Control and Prevention (CDC) during 2011-2020 were enrolled in the study. In the past decade, the annual incidence of SFTS increased over the years (P < 0.001) along with an expanding epidemic area, and the case fatality of hospitalised cases has remained high (21.3%). Although most cases occurred in hilly areas, a coastal island had the highest incidence and case fatality. The majority of cases were over the age of 60 years (72.3%), and both incidence and case fatality of SFTS increased with age. Multivariate logistic regression analysis showed that age (OR 7.47, 95% CI 1.32-42.33; P = 0.023), and haemorrhagic manifestations including petechiae (OR 7.76, 95% CI 1.17-51.50; P = 0.034), gingival haemorrhage (OR 5.38, 95% CI 1.25-23.15; P = 0.024) and melena (OR 5.75, 95% CI 1.18-28.07; P = 0.031) were significantly associated with the death of SFTS cases. Five family clusters identified were farmers, among four of which the index patients were female with a history of hypertension. Based on the study, age is a critical risk factor for incidence and case fatality of SFTS. With an increased annual incidence over the last ten years, SFTS remains a public health threat that should not be ignored. Further study is needed to look at the natural foci in the coastal islands.


Asunto(s)
Infecciones por Bunyaviridae , Phlebovirus , Síndrome de Trombocitopenia Febril Grave , Trombocitopenia , China/epidemiología , Femenino , Fiebre/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Trombocitopenia/epidemiología
2.
J Asian Nat Prod Res ; 22(6): 509-520, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30963782

RESUMEN

Two new xanthones smilone A (1), smilone B (2), and a new lignin smilgnin A (3) were isolated from the rhizomes of Smilax china L., together with three known xanthones (4-6), four lignins (7-10), two flavones (11, 12), two stilbenoids (13, 14), and ten organic phenoloids (15-24). Of them, compounds 4-6 were isolated from the genus Smilax for the first time. The structures of 1-24 were elucidated by the extensive analysis of spectral data and compared with the literature. All compounds were evaluated for their inhibitory effects against LPS-induced NO production in RAW264.7 macrophages. Among them, compound 24 exhibited significant inhibitory activity against NO production (IC50 = 1.26 µM), while compounds 3, 6, and 7 showed weak activities at the concentration of 50 µM.[Formula: see text].


Asunto(s)
Smilax , Xantonas , China , Lignina , Estructura Molecular
3.
Mikrochim Acta ; 186(11): 695, 2019 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-31612312

RESUMEN

This work reports on a modularized electrochemical method for the determination of the hormones cortisol, progesterone, testosterone and 17ß-estradiol in urine. These hormones were employed as templates when generating molecular imprints from aniline and metanilic acid by electropolymerization on the surface of screen-printed electrodes. The electrically conductive imprint was characterized by SEM, AFM and cyclic voltammetry. A four-channel system was then established to enable simultaneous determination of the hormones by cyclic voltammetry. The detection limits for cortisol, progesterone, testosterone and 17ß-estradiol are as low as 2, 2.5, 10 and 9 ag·mL-1 (for S/N = 3). Graphical abstract A four-channel system was established to enable simultaneous determination of 4 steroid hormones by cyclic voltammetry and by using moleculalry imprinted polymers.


Asunto(s)
Técnicas Electroquímicas/métodos , Estradiol/orina , Hidrocortisona/orina , Polímeros/química , Progesterona/orina , Testosterona/orina , Compuestos de Anilina/química , Técnicas Electroquímicas/instrumentación , Electrodos , Diseño de Equipo , Humanos , Límite de Detección , Impresión Molecular , Polimerizacion , Polímeros/síntesis química , Ácidos Sulfanílicos/química
4.
Environ Sci Pollut Res Int ; 30(7): 19356-19366, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36239887

RESUMEN

Pharmaceuticals and personal care products (PPCPs) as typical emerging pollutant have attracted extensive attention due to the risks to human health and environment. As a kind of harmful PPCPs, diclofenac sodium (DCF) has been frequently detected in water environment, which needs to be removed effectively. Herein, we successfully fabricated network structure composite membranes consisting of one-dimensional (1D) well-defined core-shell bacterial cellulose (BC)@MIL-100 (Fe) nanofibers by a simple but effective step-by-step strategy. The BC@MIL-100(Fe) composite membrane has three-dimensional network utilizing bacterial cellulose nanofiber as template, which was observed as the MIL-100(Fe) grew on the nanofiber uniformly and obvious core-shell structure. Impressively, the BC@MIL-100(Fe) not only possessed favorable architecture but also behaved good properties to adsorb DCF from water. As we expected, the as-obtained BC@MIL-100(Fe) composite membrane exhibited convenient recycling, high chemical stability, and short equilibrium time (30 min) with high adsorption capacity (296 mg g-1). Strikingly, in low DCF concentration solution, BC@MIL-100(Fe) composite showed high adsorption efficiency in periodic test, which can still reach 70% after five successive adsorptions without desorption. The results demonstrated that the adsorption mechanism may involve π-π interaction, H-bond interaction, and electrostatic interaction. This work proposes the new finding to understand the removing of DCF from water environment.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Humanos , Agua , Diclofenaco/química , Celulosa , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Adsorción
5.
Medicine (Baltimore) ; 101(30): e29519, 2022 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-35905211

RESUMEN

We performed a novel hydroxyapatite (HA) prosthesis implantation method in which an HA implant was implanted into the scleral shell with an autogenous scleral cap. Twenty-six patients who had undergone the novel HA prosthesis implantation method and 32 patients who had undergone traditional HA prosthesis implantation were retrospectively reviewed. The postoperative activity of the artificial eye was measured by the Hirschberg test combined with arc perimetry. The visual analog score (VAS) was used to evaluate 2-month postoperative pain and 2-month postoperative discomfort. HA implant vascularization was measured with enhanced magnetic resonance imaging (MRI) 2 and 6 months after the operation. The enhancement volume (VE) and the volume of the HA implant (VHA) were measured. All cases were followed up for 2 years. Measurement data were processed using SAS 6.12. There was a statistically significant difference (P = .016) between the percentages of excellent grade in the two groups. Two months after implantation, the median pain scores of the study and control groups were 2 and 2.5, respectively, and there was a statistically significant difference (W = 585.0, P = .004); there was a statistically significant difference (W = 535.5, P = .000) between the median discomfort scores of the study group (score = 1) and control group (score = 2); the mean VE/VHA values of the study and control groups were 0.3075 and 0.1535, respectively, and there was a statistically significant difference (t = -8.196, P = .000). Six months after implantation, the VE/VHA values of the study and control groups were 0.9686 and 0.5934, respectively, and there was a statistically significant difference (W = 549.0, P = .000). Within 2 years of postoperative follow-up, there were no serious complications in the study group. In the study group, in which the hydroxyapatite implant was implanted into a preserved scleral shell with unaltered muscles and covered with an autogenous scleral cap, postoperative activity and the fibrovascularization of the HA implant were significantly increased, and postoperative pain and discomfort were significantly reduced.


Asunto(s)
Durapatita , Esclerótica , Materiales Biocompatibles , Estudios de Cohortes , Ojo Artificial , Humanos , Órbita/cirugía , Dolor Postoperatorio/etiología , Dolor Postoperatorio/cirugía , Implantación de Prótesis/métodos , Estudios Retrospectivos , Esclerótica/trasplante
6.
Drug Des Devel Ther ; 16: 213-235, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35087267

RESUMEN

Indeed, the body articulation units, commonly referred to as body joints, play significant roles in the musculoskeletal system, enabling body flexibility. Nevertheless, these articulation units suffer from several pathological conditions, such as osteoarthritis (OA), rheumatoid arthritis (RA), ankylosing spondylitis, gout, and psoriatic arthritis. There exist several treatment modalities based on the utilization of anti-inflammatory and analgesic drugs, which can reduce or control the pathophysiological symptoms. Despite the success, these treatment modalities suffer from major shortcomings of enormous cost and poor recovery, limiting their applicability and requiring promising strategies. To address these limitations, several engineering strategies have been emerged as promising solutions in fabricating the body articulation as unit models towards local articulation repair for tissue regeneration and high-throughput screening for drug development. In this article, we present challenges related to the selection of biomaterials (natural and synthetic sources), construction of 3D articulation models (scaffold-free, scaffold-based, and organ-on-a-chip), architectural designs (microfluidics, bioprinting, electrospinning, and biomineralization), and the type of culture conditions (growth factors and active peptides). Then, we emphasize the applicability of these articulation units for emerging biomedical applications of drug screening and tissue repair/regeneration. In conclusion, we put forward the challenges and difficulties for the further clinical application of the in vitro 3D articulation unit models in terms of the long-term high activity of the models.


Asunto(s)
Materiales Biocompatibles/farmacología , Bioimpresión/métodos , Artropatías/terapia , Articulaciones/anatomía & histología , Articulaciones/fisiología , Impresión Tridimensional , Evaluación Preclínica de Medicamentos , Humanos , Medicina Regenerativa
7.
ACS Biomater Sci Eng ; 7(3): 939-962, 2021 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-33539071

RESUMEN

Indocyanine green (ICG), a near-infrared (NIR) agent with an excellent imaging performance, has captivated enormous interest from researchers owing to its excellent therapeutic and imaging abilities. Although various nanoplatforms-based drug delivery systems (DDS) with the ability to overcome the clinical limitations of ICG has been reported, ICG-medicated conventional cancer diagnosis and photorelated therapies still lack in exhibiting the therapeutic efficacy, resulting in incomplete or partly tumor elimination. In the view of addressing these concerns, various DDSs have been engineered for the efficient codelivery of combined therapeutic agents with ICG, aiming to achieve promising therapeutic results due to multifunctional imaging-guided synergistic antitumor effects. In this article, we will systematically review currently available nanoplatforms based on polymers, inorganic, proteins, and metal-organic frameworks (MOFs), among others, for codelivery of ICG along with other therapeutic agents, providing a foundation for future clinical development of ICG. In addition, codelivery systems for ICG and different mechanism-based therapeutic agents will be illustrated. In summary, we conclude the review with the challenges and perspectives of ICG-based versatile nanoplatforms in detail.


Asunto(s)
Estructuras Metalorgánicas , Neoplasias , Humanos , Verde de Indocianina , Polímeros
8.
Food Funct ; 11(6): 5133-5141, 2020 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-32432306

RESUMEN

The applications of carvacrol are limited due to its poor stability and water solubility, and high volatility; however, ovalbumin can be used to encapsulate hydrophobic molecules, improve their aqueous solubility, and reduce their volatility. In this study, we fabricated ovalbumin-carvacrol nanoparticles (OCGns) under different pH (2, 5, 7, and 9) conditions using a gel embedding method and investigated their physicochemical and antibacterial properties. Rheological experiments revealed that the G' of ovalbumin gels (OGs) prepared under different pH conditions were OG-2 > OG-7 > OG-9 > OG-5. Carvacrol addition reduced the tight structure of ovalbumin and carvacrol under pH 5 and 7 conditions, with hardness first decreasing and then increasing, but increasing under pH 2 and 9 conditions. Fluorescence and infrared spectroscopy indicated complex formation, with carvacrol increasing the average diameter of nanoparticles prepared at pH 2, 5, 7, and 9. Encapsulation reached 89.34 and 91.86% at pH 2 and 9, respectively; however, inhibition experiments revealed that the minimum inhibitory concentration of OCGn-2 against Gram-positive Bacillus cereus and Salmonella (0.08 and 0.16 mg mL-1, respectively) was lower than that of OCGn-9 (both 0.28 mg mL-1). Moreover, OCGn-2 possessed a better dense gel structure and a higher stability, encapsulation rate, and antibacterial activity, suggesting that pH affects gel microstructure and thus the encapsulation efficiency and bacteriostatic properties of the prepared nanoparticles. These results contribute to our knowledge of the design and fabrication of polymeric nanoparticle delivery systems for bioactive compounds with beneficial properties.


Asunto(s)
Antibacterianos/farmacología , Bacillus cereus/efectos de los fármacos , Cimenos/farmacología , Nanogeles , Ovalbúmina , Salmonella/efectos de los fármacos , Cimenos/química , Concentración de Iones de Hidrógeno , Pruebas de Sensibilidad Microbiana , Nanocápsulas , Tamaño de la Partícula , Reología , Solubilidad
9.
Biosens Bioelectron ; 150: 111901, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-31767344

RESUMEN

Molecularly imprinted polymers (MIPs) have been developed to replace antibodies for the recognition of target molecules (such as antigens), and have been integrated into electrochemical sensing approaches by polymerization onto an electrode. Electrochemical sensing is inexpensive and flexible, and has demonstrated utility in point-of-care devices. In this work, several 2D (conductive) materials were employed to improve the performance of MIP sensors. Screen-printed electrodes were coated by the electropolymerization of aniline and metanilic acid, commingled with target molecules and various 2D materials. Tungsten disulfide (WS2) with an average particle size of 2 µm was found to increase the sensitivity of detection of molecularly imprinted conductive polymer-coated electrodes to 17ß-estradiol. As estradiol concentrations are important to eel aquaculture, we screened eel serum samples to determine their 17ß-estradiol concentrations, which were found to be in the range 28.2 ± 3.6 to 73.0 ± 11.6 pg/mL after dilution. These results were in agreement with measurements using commercial immunoanalysis.


Asunto(s)
Anguilas/sangre , Estradiol/sangre , Polímeros/química , Animales , Técnicas Biosensibles/métodos , Conductividad Eléctrica , Electrodos , Femenino , Límite de Detección , Metales/química , Impresión Molecular/métodos , Polimerizacion
10.
Adv Mater ; 32(29): e2001459, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32484308

RESUMEN

Near-infrared (NIR) activatable upconversion nanoparticles (UCNPs) enable wireless-based phototherapies by converting deep-tissue-penetrating NIR to visible light. UCNPs are therefore ideal as wireless transducers for photodynamic therapy (PDT) of deep-sited tumors. However, the retention of unsequestered UCNPs in tissue with minimal options for removal limits their clinical translation. To address this shortcoming, biocompatible UCNPs implants are developed to deliver upconversion photonic properties in a flexible, optical guide design. To enhance its translatability, the UCNPs implant is constructed with an FDA-approved poly(ethylene glycol) diacrylate (PEGDA) core clad with fluorinated ethylene propylene (FEP). The emission spectrum of the UCNPs implant can be tuned to overlap with the absorption spectra of the clinically relevant photosensitizer, 5-aminolevulinic acid (5-ALA). The UCNPs implant can wirelessly transmit upconverted visible light till 8 cm in length and in a bendable manner even when implanted underneath the skin or scalp. With this system, it is demonstrated that NIR-based chronic PDT is achievable in an untethered and noninvasive manner in a mouse xenograft glioblastoma multiforme (GBM) model. It is postulated that such encapsulated UCNPs implants represent a translational shift for wireless deep-tissue phototherapy by enabling sequestration of UCNPs without compromising wireless deep-tissue light delivery.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Fotoquimioterapia/instrumentación , Polietilenglicoles/química , Tecnología Inalámbrica , Ácido Aminolevulínico/química , Ácido Aminolevulínico/farmacología , Animales , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Transformación Celular Neoplásica , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Ratones , Nanopartículas/química , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología
11.
J Hazard Mater ; 364: 645-653, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30408766

RESUMEN

The treatment of low-level radioactive wastewater is a critical and considerable challenge. Bacterial cellulose membrane (BCM) modified with ethylenediaminetetraacetic acid (EDTA) using (3-aminopropyl) triethoxysilane (APTES) as a crosslinker were used to remove Sr2+ in this work. SEM, XPS, and FTIR were used to characterize the morphology, structure, chemical shift, and functional groups of the as-prepared adsorbent. The synthesized BCM@APTES-EDTA presented a three-layer structure of membrane-net-membrane with nano-sized fibers (<100 nm). The adsorption of Sr2+ onto BCM@APTES-EDTA was investigated as a function of contact time and initial concentration of Sr2+. Results showed that the adsorption of Sr2+ followed the pseudo second-order kinetic model (R2 = 0.999), and fitted well with the Langmuir isotherm model (R2 = 0.996). The maximum adsorption capacity was calculated to be 44.86 mg g-1, which was comparable to other adsorbents. Additionally, the mechanism of Sr2+ adsorbed by the as-prepared adsorbent was studied through FTIR and XPS analysis, which indicated that the tertiary amines and carboxylate from grafted EDTA participated in the adsorption of Sr2+.


Asunto(s)
Celulosa/química , Quelantes/química , Ácido Edético/química , Nanofibras/química , Estroncio/química , Contaminantes Químicos del Agua/química , Acetobacter , Adsorción , Membranas Artificiales , Propilaminas/química , Silanos/química , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos
12.
Food Res Int ; 126: 108604, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31732021

RESUMEN

This work aimed to develop a novel colorimetric indicator film for monitoring of food freshness based on gelatin/polyvinyl alcohol matrix incorporated with anthocyanin extracts from mulberry. The color of anthocyanin extracts solutions obviously changed from bright red to dark green in the pH range of 2.0-11.0. FTIR spectra and isothermal titration calorimetry showed that the anthocyanin extracts were successfully combined with gelatin/polyvinyl alcohol matrix by hydrogen binding and electrostatic interaction, which enhanced the stability of anthocyanin. The scanning electric microscopy showed that the compatibility between polyvinyl alcohol and gelatin were improved owing to the addition of anthocyanin extracts. With the anthocyanin extracts addition from 0 to 45 mg/100 mL mixed solution, the tensile strength decreased from 30.80 to 21.01 MPa and the elongation at break increased from 589.22% to 905.86%. The color response of film in buffer solution of different pH were in accordance with anthocyanin extracts solutions, and its color changes were clearly visible with naked eye. Finally, the film was evaluated by a test on monitoring fish spoilage, which presented visible color changes due to volatile nitrogenous compounds formed over time. These results showed that this developed film could be used as an effective method for the monitoring of food freshness.


Asunto(s)
Antocianinas/química , Embalaje de Alimentos/instrumentación , Indicadores y Reactivos/química , Morus/química , Alcohol Polivinílico/química , Alimentos Marinos , Animales , Colorimetría , Peces , Almacenamiento de Alimentos/instrumentación , Gelatina/química , Enlace de Hidrógeno , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Extractos Vegetales/química , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática
13.
Front Public Health ; 7: 344, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31824910

RESUMEN

Background: The growth rate of centenarians was unusually rapid in recent decades, ushering in an era of longevity. This study aims to explore the difference between centenarians and non-centenarians using quantitative research, and to scientifically guide residents to develop the correct lifestyle and health care ways. Methods: From October 2013 to August 2017. A cross-sectional survey was conducted on 271 centenarians and 570 non-centenarians by using a questionnaire to assess longevity and health issues which was developed for the needs of the study, who came from 29 counties and districts in 11 cities of Zhejiang province, China. Two hundred and fifty-five valid questionnaires were returned, with an effective response rate of 94.1%. Meanwhile, data of 526 non-centenarians from Zhejiang province was collected as a control group, with an effective response rate of 92.3%. Results: The prevalence rates of tumor, stomach and duodenal ulcer, diabetes, bronchial asthma, and chronic obstructive pulmonary disease, tuberculosis among centenarians were all lower than those among non-centenarians. The oral health of centenarians is better than that of non-centenarians. The consumption of coarse cereals, pasta, other staple foods and fruits among centenarians was higher than that of non-centenarians. The percentage of centenarians who smoke or engage in recreational activities every day was lower than that of non-centenarians. Conclusions: We should give full play to the role of preventive medicine and health management to safeguard the health of residents. Pay attention to oral health, and develop the good habit of loving teeth. The diet should be rich and varied, and increase the intake of grains and fruits. Give up smoking, limit alcohol, spirit-preserving with calming, follow the law of scientific regimen.

14.
Environ Sci Pollut Res Int ; 24(35): 26919-26926, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26146370

RESUMEN

Measuring the content of hydrogen chloride (HCl) in exhaust gas used to take time and energy. In this paper, we introduce a new online monitoring system which can output real-time data to the monitoring center. The system samples and cools exhaust gas, and after a series of processing, it will be analyzed by a specific instrument. The core part of this system is remote terminal unit (RTU) which is designed on Cortex-A8 embedded architecture. RTU runs a scaled-down version of Linux which is a good choice of OS for embedded applications. It controls the whole processes, does data acquisition and data analysis, and communicates with monitoring center through Ethernet. In addition, through a software developed for windows, the monitoring process can be remotely controlled. The new system is quite beneficial for steel industry to do environment monitoring.


Asunto(s)
Monitoreo del Ambiente/instrumentación , Ácido Clorhídrico/análisis , Metalurgia , Sistemas en Línea , Acero , Emisiones de Vehículos/análisis
15.
Mol Med Rep ; 15(1): 305-308, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27959436

RESUMEN

Joubert syndrome (JS) is an autosomal recessive disorder, which is characterized by hypotonia, ataxia, psychomotor delay, and variable occurrences of oculomotor apraxia and neonatal breathing abnormalities. JS is clinically and genetically heterogeneous. The present study investigated a typical JS family. The 'molar tooth sign' was observed in the proband through magnetic resonance imaging. Other symptoms of JS include cerebellar vermis hypoplasia/dysplasia, oculomotor apraxia and intellectual disability. High­throughput sequencing revealed that JS was caused by coiled­coil and C2 domain containing 2A (CC2D2A) compound heterozygous mutations. One CC2D2A allele was affected with a missense mutation, c.2581G>A, which led to a p.Asp861Asn amino acid replacement. The other allele was affected with a c.2848C>T nonsense mutation, which resulted in a truncated CC2D2A protein (p.Arg950Ter). Both of these alterations are novel. Further investigation indicated that the proband's father was the c.2581G>A carrier, whereas the mother was the c.2848C>T carrier. These results indicated that JS in the proband was caused by novel compound heterozygous mutations in CC2D2A, which were inherited from both parents. These findings may be used to establish prenatal molecular diagnostic criteria, which may be beneficial in future pregnancies.


Asunto(s)
Anomalías Múltiples/genética , Cerebelo/anomalías , Anomalías del Ojo/genética , Enfermedades Renales Quísticas/genética , Mutación , Proteínas/genética , Retina/anomalías , Anomalías Múltiples/diagnóstico por imagen , Anomalías Múltiples/patología , Tronco Encefálico/diagnóstico por imagen , Tronco Encefálico/patología , Cerebelo/diagnóstico por imagen , Cerebelo/patología , Proteínas del Citoesqueleto , Análisis Mutacional de ADN , Anomalías del Ojo/diagnóstico por imagen , Anomalías del Ojo/patología , Femenino , Heterocigoto , Humanos , Lactante , Enfermedades Renales Quísticas/diagnóstico por imagen , Enfermedades Renales Quísticas/patología , Masculino , Linaje , Retina/diagnóstico por imagen , Retina/patología
16.
Bioresour Technol ; 227: 102-111, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28013126

RESUMEN

Membrane fouling is an important issue for membrane bioreactor (MBR) operation. This paper aims at the investigation and the controlling of reversible membrane fouling due to cake layer formation and foulants deposition by optimizing MBR hydrodynamics through the combination of computational fluid dynamics (CFD) and design of experiment (DOE). The model was validated by comparing simulations with measurements of liquid velocity and dissolved oxygen (DO) concentration in a lab-scale submerged MBR. The results demonstrated that the sludge concentration is the most influencing for responses including shear stress, particle deposition propensity (PDP), sludge viscosity and strain rate. A medium sludge concentration of 8820mgL-1 is optimal for the reduction of reversible fouling in this submerged MBR. The bubble diameter is more decisive than air flowrate for membrane shear stress due to its role in sludge viscosity. The optimal bubble diameter was at around 4.8mm for both of shear stress and PDP.


Asunto(s)
Reactores Biológicos , Modelos Teóricos , Incrustaciones Biológicas , Simulación por Computador , Diseño de Equipo , Hidrodinámica , Membranas Artificiales , Oxígeno/metabolismo , Tamaño de la Partícula , Aguas del Alcantarillado , Estrés Mecánico , Viscosidad
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(8): 1483-6, 2006 Aug.
Artículo en Zh | MEDLINE | ID: mdl-17058952

RESUMEN

A pH sensitive polymer was prepared by copolymerization of methacrylic acid as monomer, diethylene glycol dimethacrylate as cross-linking reagent, heptane as porogen, and fluorescent dye eosin as indicator. The factors of influence on the preparation, and the character of the pH sensitive polymer for pH were studied. The maximal emission wavelength of eosin was red shifted in the polymer than in solution, the apparent Ka largened, and the dissociation equilibrium of indicator was shifted to acidity direction, because the polarity of polymer diminished. Under the optimal condition, the calibration curve of the pH sensitive polymer covered the range of pH 0-3.0 with good reproduction and reversibility.


Asunto(s)
Metacrilatos/química , Polímeros/química , Acrilatos/química , Eosina Amarillenta-(YS)/química , Glicoles de Etileno/química , Heptanos/química , Concentración de Iones de Hidrógeno , Polímeros/síntesis química , Espectrometría de Fluorescencia
18.
Water Res ; 88: 293-300, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26512807

RESUMEN

Sodium hypochlorite (NaClO) is a commonly used reagent for membrane cleaning in membrane bioreactors (MBRs), while it, being a kind of disinfectant (oxidant), may impair viability of microbes or even totally inactivate them upon its diffusion into mixed liquor during membrane cleaning. In this study, we systematically examine the effects of NaClO on microorganisms in terms of microbial cell integrity, metabolism behaviours (key enzymes), and intracellular reactive oxygen species (ROS) under various NaClO concentrations. Different proportions of microbial cells in activated sludge were damaged within several minutes dependent on NaClO dosages (5-50 mg/g-SS), and correspondingly organic matters were released to bulk solution. Inhibition of key enzymes involved in organic matter biodegradation, nitrification and denitrification was observed in the presence of NaClO above 1 mg/g-SS, and thus organic matter and nitrogen removal efficiencies were decreased. It was also demonstrated that intracellular ROS production was increased with the NaClO dosage higher than 1 mg/g-SS, which likely induced further damage to microbial cells.


Asunto(s)
Incrustaciones Biológicas/prevención & control , Reactores Biológicos/microbiología , Membranas Artificiales , Consorcios Microbianos/efectos de los fármacos , Hipoclorito de Sodio/farmacología , Adenosina Trifosfato/metabolismo , Membrana Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Consorcios Microbianos/fisiología , Oxidorreductasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Aguas del Alcantarillado/microbiología , Hipoclorito de Sodio/administración & dosificación , Hipoclorito de Sodio/química , Eliminación de Residuos Líquidos/instrumentación , Eliminación de Residuos Líquidos/métodos
19.
Adv Healthc Mater ; 5(21): 2813-2822, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27717239

RESUMEN

Benzaldehyde-terminated telechelic four-armed polyethylene glycol (PEG-BA) is synthesized and cross-linked with carboxymethyl chitosan (CMC) to form dynamic hydrogels with strong mechanical performance. The gelation temperature and time, mechanical performance, and self-healing behaviors are systematically investigated. The hydrogels have good storage modulus up to 3162.06 ± 21.06 Pa, comparable to conventional bulk hydrogels. The separated alternate hydrogel lines connect together to become an integrated hydrogel film after 5 min at room temperature without any external intervention. This is due to the dynamic equilibrium between the Schiff base linkages and the aldehyde groups of PEG-BA and amine groups on CMC backbone. The hydrogel shows excellent cytocompatibility and the cell viability is as high as 90.7 ± 6.8% after 2 d 3D encapsulation in the hydrogel. In vivo tests indicate that the hydrogels can effectively stop bleeding when the hydrogel is directly injected into a rabbit liver incision. The total blood loss is reduced from 0.65 ± 0.10 g to 0.29 ± 0.11 g, and the hemostasis time is decreased from 167 ± 21 s to 120 ± 10 s, when compared to a gauze treatment with physical compression. These self-healing hydrogels have potential to be used as a novel hemostatic material.


Asunto(s)
Hemostáticos/química , Hemostáticos/farmacología , Hidrogeles/química , Hidrogeles/farmacología , Animales , Benzaldehídos/química , Benzaldehídos/farmacología , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Hemorragia/tratamiento farmacológico , Humanos , Imidas/química , Hígado/efectos de los fármacos , Morfolinas/química , Polietilenglicoles/química , Conejos , Temperatura
20.
Bioresour Technol ; 219: 566-575, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27540633

RESUMEN

Cost-effective membrane fouling control and nitrogen removal performance are of great concern in airlift external circulation membrane bioreactors (AEC-MBRs). Computational fluid dynamics (CFD) model incorporating sub-models of bio-kinetics, oxygen transfer and sludge rheology was developed for the cost-effective optimization of a lab-scale AEC-MBR. The model was calibrated and validated by extensive measurements of water velocities and water quality parameters in the AEC-MBR. The validated results demonstrated that the optimized height of gas-liquid dispersion was at around 300mm. The shear stress on membrane surface was equalized and had an average value of 1.2Pa under an air flowrate of 1.0m(3)h(-1). The model further revealed that the high nitrogen removal efficiency (>90%) was achieved due to the high recirculation ratio driven by airlift force without destroying the oxygen deprivation and enrichment in the anoxic and oxic zone, respectively.


Asunto(s)
Reactores Biológicos , Simulación por Computador , Membranas Artificiales , Modelos Teóricos , Nitrógeno/aislamiento & purificación , Aguas del Alcantarillado/química , Biodegradación Ambiental , Desnitrificación , Hidrodinámica , Cinética , Oxígeno
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