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1.
Biomacromolecules ; 25(6): 3731-3740, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38712827

RESUMO

Interface engineering is essential for cellulosic fiber-reinforced polymer composites to achieve high strength and toughness. In this study, carboxymethyl cellulose (CMC) functionalized with hydrophobic quaternary ammonium ions (QAs) were utilized to modify the interface between holocellulose fibers (HF) and acrylic resin. The wet HF/CMC papers were prepared by vacuum filtration, akin to papermaking, followed by cationic ion exchange with different hydrophobic QAs. Subsequently, the modified papers were dried, impregnated with an acrylic resin monomer, and cured to produce transparent composite films. The effect of the hydrophobic QA moieties on the structure and optical and mechanical properties of the HF/CMC/acrylic resin composites were investigated. The composite film with cetyltrimethylammonium (CTA)-functionalized CMC showed high optical transmittance (87%) with low haze (43%), while the composite film with phenyltrimethylammonium (PTMA)-functionalized CMC demonstrated high Young's modulus of 7.6 GPa and high tensile strength of 180 MPa. These properties are higher than those of the composites prepared through covalent interfacial modification strategies. The results highlighted the crucial role of hydrophobic functionalized CMCs in facilitating homogeneous resin impregnation in the HF fiber network, producing a composite with enhanced interfacial adhesion strength, increased optical transparency, and mechanical strength. This facile use of hydrophobic CMCs as interfacial compatibilizers provides an energy-efficient route for preparing transparent, thin, and flexible composite films favorable in optoelectronic applications.


Assuntos
Resinas Acrílicas , Carboximetilcelulose Sódica , Interações Hidrofóbicas e Hidrofílicas , Resistência à Tração , Carboximetilcelulose Sódica/química , Resinas Acrílicas/química , Compostos de Amônio Quaternário/química , Celulose/química , Módulo de Elasticidade
2.
Biomacromolecules ; 25(8): 4797-4808, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38976360

RESUMO

Interfibrillar phases and bonding in cellulose nanofibril (CNF)-based composites are crucial for materials performances. In this study, we investigated the influence of CNF surface characteristics, the guluronic acid/mannuronic acid ratio, and the molecular weight of alginates on the structure, mechanical, and barrier properties of CNF/alginate composite films. Three types of CNFs with varying surface charges and nanofibril dimensions were prepared from wood pulp fibers. The interfacial bonding through calcium ion cross-linking between alginate and carboxylated CNFs (TCNFs) led to significantly enhanced stiffness and strength due to the formation of an interpenetrating double network, compared to composites from alginates and CNFs with native negative or cationic surface charges. Various alginates extracted from Alaria esculenta (AE) and Laminaria hyperborea (LH) were also examined. The TCNF/AE composite, prepared from alginate with a high mannuronic acid proportion and high molecular weight, exhibited a Young's modulus of 20.3 GPa and a tensile strength of 331 MPa under dry conditions and a Young's modulus of 430 MPa and a tensile strength of 9.3 MPa at the wet state. Additionally, the TCNF/AE composite demonstrated protective properties as a barrier coating for fruit, significantly reducing browning of banana peels and weight loss of bananas stored under ambient conditions.


Assuntos
Alginatos , Celulose , Nanofibras , Resistência à Tração , Alginatos/química , Celulose/química , Nanofibras/química , Laminaria/química , Módulo de Elasticidade , Peso Molecular , Ácidos Hexurônicos/química
3.
Dent Traumatol ; 40(4): 435-443, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38459650

RESUMO

BACKGROUND/AIM: Results of studies investigating the association between traumatic brain injury (TBI) and maxillofacial fractures (MFs) have varied considerably. The present study aimed to evaluate the correlation between TBIs and MFs, as well as the impact of age, sex, trauma mechanism, and season on TBIs. MATERIALS AND METHODS: This 12-year retrospective study of 2841 patients used univariate and multivariate logistic regression to assess the association between MFs and other factors impacting TBIs. RESULTS: Among 2841 patients, 1978 TBIs occurred in 829 (29.2%), with intracranial injuries (n = 828) is the most common. Of 829 patients with TBIs, 688 were male and 141 were female, corresponding to a male-to-female ratio of 4.9:1.0. The most common age group was 40-49 years (24.6%). Vehicles (including motor vehicles and electric vehicles) accidents were the primary causes of injuries. Multivariate regression analyses revealed an increased risk for TBIs among males (odds ratio [OR] 0.632, p < 0.001). Patients >40 years of age were at higher risk for TBIs, especially those ≥70 years (OR 3.966, p = 0.001). Vehicle accidents were a high-risk factor for TBIs (OR 6.894, p < 0.001), and winter was the most prevalent season for such injuries (OR 1.559, p = 0.002). Risk for TBI increased by 136.4% in combined midfacial and mandibular fractures (p = 0.016) and by 101.6% in multiple midfacial fractures (p = 0.045). TBIs were less common in single mandibular fractures, notably in single-angle fractures, with a risk of only 0.204-fold. CONCLUSION: TBIs in MFs were significantly correlated with sex, age, aetiology, season and fracture location. Maxillofacial surgeons and emergency physicians must be aware of the possible association between TBIs and MFs to assess and manage this complicated relationship in a timely manner.


Assuntos
Lesões Encefálicas Traumáticas , Traumatismos Maxilofaciais , Humanos , Masculino , Estudos Retrospectivos , Feminino , Adulto , Pessoa de Meia-Idade , Lesões Encefálicas Traumáticas/epidemiologia , Lesões Encefálicas Traumáticas/complicações , Idoso , Adolescente , Criança , Fatores de Risco , Traumatismos Maxilofaciais/epidemiologia , Pré-Escolar , Estações do Ano , Idoso de 80 Anos ou mais , Fatores Sexuais , Lactente , Fatores Etários , Fraturas Cranianas/epidemiologia , Fraturas Cranianas/complicações
4.
AAPS PharmSciTech ; 25(3): 40, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38366100

RESUMO

Respiratory tract infections caused by multi-drug-resistant (MDR) bacteria have been a severe risk to human health. Colistin is often used to treat the MDR Gram-negative bacterial infections as a last-line therapy. Inhaled colistin can achieve a high concentration in the lung but none of aerosolized colistin products has been approved in the USA. Liposome has been reported as an advantageous formulation strategy for antibiotics due to its controlled release profile and biocompatibility. We have developed colistin liposomal formulations in our previous study. In the present study, the cellular uptake and transport of colistin in colistin liposomes were examined in two human lung epithelium in vitro models, Calu-3 monolayer and EpiAirway 3D tissue models. In both models, cellular uptake (p < 0.05) and cellular transport (p < 0.01) of colistin were significantly reduced by the colistin liposome compared to the colistin solution. Our findings indicate that inhaled colistin liposomes could be a promising treatment for extracellular bacterial lung infections caused by MDR Pseudomonas aeruginosa (P. aeruginosa).


Assuntos
Colistina , Infecções por Pseudomonas , Humanos , Colistina/farmacologia , Lipossomos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pulmão , Pseudomonas aeruginosa
5.
Small ; 19(17): e2205056, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36703510

RESUMO

Nature has evolved elegant ways to alter the wood cell wall structure through carbohydrate-active enzymes, offering environmentally friendly solutions to tailor the microstructure of wood for high-performance materials. In this work, the cell wall structure of delignified wood is modified under mild reaction conditions using an oxidative enzyme, lytic polysaccharide monooxygenase (LPMO). LPMO oxidation results in nanofibrillation of cellulose microfibril bundles inside the wood cell wall, allowing densification of delignified wood under ambient conditions and low pressure into transparent anisotropic films. The enzymatic nanofibrillation facilitates microfibril fusion and enhances the adhesion between the adjacent wood fiber cells during densification process, thereby significantly improving the mechanical performance of the films in both longitudinal and transverse directions. These results improve the understanding of LPMO-induced microstructural changes in wood and offer an environmentally friendly alternative for harsh chemical treatments and energy-intensive densification processes thus representing a significant advance in sustainable production of high-performance wood-derived materials.


Assuntos
Celulose , Madeira , Celulose/química , Madeira/química , Polissacarídeos , Oxirredução , Oxigenases de Função Mista/metabolismo , Estresse Oxidativo
6.
Crit Rev Food Sci Nutr ; 63(15): 2348-2365, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34590971

RESUMO

Docosahexaenoic acid (C22: 6n-3, DHA) and eicosapentaenoic acid (C20: 5n-3, EPA) have been shown to provide the opportunity to inhibit onset and escalation of chronic diseases. Nevertheless, their undesirable characteristics including poor water solubility, oxidation sensitivity, high melting point and unpleasant sensory attributes hinder their application in the food industry. In recent years, utilizing food-grade delivery systems to deliver DHA/EPA and improve their biological efficacy has emerged as an attractive approach with fascinating prospects. This review focuses on introducing potential delivery systems for DHA/EPA, including microemulsions, nanoemulsions, Pickering emulsions, hydrogels, lipid particles, oleogels, liposomes, microcapsules and micelles. The opportunities, fabrication and characterization of these delivery systems loaded with DHA/EPA are highlighted. Besides, food sources of DHA/EPA, their benefits to the human body and a series of challenges for effective utilization of DHA/EPA are discussed. Promising future research trends of food-grade systems for delivery of DHA/EPA are also presented. Conducting in vivo experiments, applying DHA/EPA-loaded delivery systems into real food, improving the applicability of such delivery systems in industrial production, co-encapsulating DHA/EPA with other substances, seeking measures to improve the performance of existing delivery systems and developing novel food-grade delivery systems inspired by other fields are various future considerations.


Assuntos
Ácidos Docosa-Hexaenoicos , Ácido Eicosapentaenoico , Humanos , Ácidos Docosa-Hexaenoicos/farmacologia , Alimentos , Oxirredução , Lipossomos
7.
Soft Matter ; 19(28): 5249-5261, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37282665

RESUMO

Microcapsules with liquid cores encapsulated by thin membranes have many applications in science, medicine and industry. In this paper, we design a suspension of microcapsules which can flow and deform like red blood cells (RBCs), as a valuable tool to investigate microhaemodynamics. A reconfigurable and easy-to-assemble 3D nested glass capillary device is used to robustly fabricate water-oil-water double emulsions which are then converted into spherical microcapsules with hyperelastic membranes by cross-linking the polydimethylsiloxane (PDMS) layer coating the droplets. The resulting capsules are monodisperse to within 1% and can be made in a wide range of size and membrane thickness. We use osmosis to deflate by 36% initially spherical capsules of diameter 350 µm and a membrane thickness of 4% of their radius. Hence, we can match the reduced volume of RBCs but not their biconcave shape, since our capsules adopt a buckled shape. We compare the propagation of initially spherical and deflated capsules under constant volumetric flow in cylindrical capillaries of different confinements. We find that only deflated capsules deform broadly like RBCs over a similar range of capillary numbers Ca - the ratio of viscous to elastic forces. Similarly to the RBCs, the microcapsules transition from a symmetric 'parachute' to an asymmetric 'slipper'-like shape as Ca increases within the physiological range, demonstrating intriguing confinement-dependent dynamics. In addition to biomimetic RBC properties, high-throughput fabrication of tunable ultra-soft microcapsules could be further functionalized and find applications in other areas of science and engineering.


Assuntos
Biomimética , Eritrócitos , Cápsulas , Água , Dimetilpolisiloxanos , Emulsões
8.
Analyst ; 147(6): 1055-1059, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35191913

RESUMO

Herein, we report an extended-gate-type organic field-effect transistor (OFET) sensor for oxytocin. The fabricated OFET-based immunosensor has successfully detected oxytocin at a ppt level in human saliva with high recovery rates (96-102%). We believe our sensor would pave the way for the realization of portable sensors for healthcare monitoring.


Assuntos
Técnicas Biossensoriais , Ocitocina , Eletrodos , Humanos , Imunoensaio , Saliva , Transistores Eletrônicos
9.
BMC Cancer ; 21(1): 661, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078317

RESUMO

PURPOSE: To evaluate the effectiveness and safety of pegylated recombinant human granulocyte colony stimulating factor (PEG-rhG-CSF) in preventing neutropenia during chemoradiotherapy in patients with cervical cancer. METHODS: From August 2018 to April 2020, 60 patients who were pathologically confirmed as cervical cancer were randomly divided into two groups at a ratio of 2:1: PEG-modified-rhG-CSF experimental group and control group. The primary endpoints were the incidence of grade 3-4 neutropenia. Secondary endpoints included the duration of grade 3-4 neutropenia, the incidence of grade 4 neutropenia, the incidence of febrile neutropenia (FN), delay rate of chemotherapy, prolonged time of chemotherapy, time to complete radiotherapy and safety. RESULTS: The incidence of grade 3-4 neutropenia in the experimental group was significantly lower than the control group (10% vs. 77.78%, P < 0.001). However, there was no statistical significance between the two groups in the duration of grade 3-4 neutropenia (3.75 days vs. 5.07 days, P = 0.871). The experimental group was better than the control group in the incidence of grade 4 neutropenia, the incidence of FN and delay rate of chemotherapy, and the difference was statistically significant (P < 0.05). Besides, the prolonged time of chemotherapy and the time to complete radiotherapy in the experimental group were less than those in the control group, but the difference was not statistically significant (P > 0.05). The incidence of adverse events in the experimental group and control group were 55.00 and 94.44%, respectively, and the difference was statistically significant (P = 0.003). CONCLUSION: PEG-rhG-CSF preventive treatment used in the course of chemoradiotherapy for patients with cervical cancer can reduce the incidence of neutropenia and improve the incidence of delayed chemotherapy cycles. TRIAL REGISTRATION: ClinicalTrials.gov , NCT04542356 . Registered 9 September 2020 - Retrospectively registered.


Assuntos
Carcinoma de Células Escamosas/terapia , Quimiorradioterapia/efeitos adversos , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Neutropenia/epidemiologia , Polietilenoglicóis/administração & dosagem , Neoplasias do Colo do Útero/terapia , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Escamosas/patologia , Quimiorradioterapia/métodos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Feminino , Fator Estimulador de Colônias de Granulócitos/efeitos adversos , Humanos , Incidência , Injeções Subcutâneas , Pessoa de Meia-Idade , Neutropenia/diagnóstico , Neutropenia/etiologia , Neutropenia/prevenção & controle , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Polietilenoglicóis/efeitos adversos , Índice de Gravidade de Doença , Resultado do Tratamento , Neoplasias do Colo do Útero/patologia , Adulto Jovem
10.
Pharmacol Res ; 169: 105636, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33932606

RESUMO

Proparacaine (PPC) is a previously discovered topical anesthetic for ophthalmic optometry and surgery by blocking the central Nav1.3. In this study, we found that proparacaine hydrochloride (PPC-HCl) exerted an acute robust antiepileptic effect in pilocarpine-induced epilepsy mice. More importantly, chronic treatment with PPC-HCl totally terminated spontaneous recurrent seizure occurrence without significant toxicity. Chronic treatment with PPC-HCl did not cause obvious cytotoxicity, neuropsychiatric adverse effects, hepatotoxicity, cardiotoxicity, and even genotoxicity that evaluated by whole genome-scale transcriptomic analyses. Only when in a high dose (50 mg/kg), the QRS interval measured by electrocardiography was slightly prolonged, which was similar to the impact of levetiracetam. Nevertheless, to overcome this potential issue, we adopt a liposome encapsulation strategy that could alleviate cardiotoxicity and prepared a type of hydrogel containing PPC-HCl for sustained release. Implantation of thermosensitive chitosan-based hydrogel containing liposomal PPC-HCl into the subcutaneous tissue exerted immediate and long-lasting remission from spontaneous recurrent seizure in epileptic mice without affecting QRS interval. Therefore, this new liposomal hydrogel formulation of proparacaine could be developed as a transdermal patch for treating epilepsy, avoiding the severe toxicity after chronic treatment with current antiepileptic drugs in clinic.


Assuntos
Anticonvulsivantes/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Epilepsia/tratamento farmacológico , Propoxicaína/uso terapêutico , Animais , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/efeitos adversos , Eletroencefalografia , Elevação dos Membros Posteriores , Hidrogéis , Lipossomos/administração & dosagem , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Teste de Campo Aberto/efeitos dos fármacos , Propoxicaína/administração & dosagem , Propoxicaína/efeitos adversos
11.
Nanomedicine ; 29: 102262, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32623017

RESUMO

Tenacious sputum poses a critical diffusion barrier for aerosol antibiotics used to treat cystic fibrosis (CF) lung infection. We conducted a proof-of-concept study using dense poly(ethylene glycol) coated polystyrene nanoparticles (PS-PEG NPs) as model muco-inert particles (MIPs) formulated as a powder using an excipient enhanced growth (EEG) strategy, aiming to minimize extrathoracic airway loss, maximize deposition in the airway and further overcome the sputum barrier in the CF lungs. The EEG aerosol formulation containing PS-PEG MIPs was prepared by spray drying and produced discrete spherical particles with geometric diameter of approximately 2 µm; and >80% of the powder dose was delivered from a new small-animal dry powder inhaler (DPI). The MIPs released from the EEG aerosol had human airway mucus and CF sputum diffusion properties comparable to the suspension formulation. These properties make this formulation a promising pulmonary drug delivery system for CF lung infections.


Assuntos
Fibrose Cística/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Pneumopatias/tratamento farmacológico , Pulmão/efeitos dos fármacos , Nanopartículas/química , Administração por Inalação , Fibrose Cística/patologia , Inaladores de Pó Seco/métodos , Excipientes/química , Humanos , Pulmão/crescimento & desenvolvimento , Pneumopatias/patologia , Muco/efeitos dos fármacos , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Poliestirenos/química , Poliestirenos/farmacologia
12.
Mol Pharm ; 15(5): 2045-2053, 2018 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-29641898

RESUMO

Surface composition critically impacts stability (e.g., crystallization) and performance (e.g., dissolution) of spray dried amorphous solid dispersion (ASD) formulations; however, traditional characterization techniques such as Raman and infrared spectroscopies may not provide useful information on surface composition on the spray dried ASD particles due to low spatial resolution, high probing depth, and lack of quantitative information. This study presents an advanced surface characterization platform consisting of two complementary techniques: X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Such a platform enables qualitative and quantitative measurements of surface composition for the fine spray dried ASD particles with ultrasurface-sensitivity (less than 10 nm from the surface) and superior spatial resolution (approximately 250 nm for ToF-SIMS). Both XPS and ToF-SIMS demonstrated that the polymer (PVPVA) was dominantly enriched on the surface of our spray dried naproxen-PVPVA ASD particles. Of a particular note was that XPS could differentiate two batches of spray dried ASD particles with a subtle difference in surface composition produced by varying feed solution solvents. This advanced surface characterization platform will provide essential surface information to understand the mechanisms underlying the impact of surface composition on stability (e.g., crystallization) and functionality (e.g., dissolution) in future studies.


Assuntos
Naproxeno/química , Química Farmacêutica/métodos , Estabilidade de Medicamentos , Espectrometria de Massas/métodos , Espectroscopia Fotoeletrônica/métodos , Polímeros/química , Povidona/análogos & derivados , Povidona/química , Solubilidade/efeitos dos fármacos , Solventes/química , Propriedades de Superfície
13.
Biomacromolecules ; 19(10): 4075-4083, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30130395

RESUMO

Multifunctional lightweight, flexible, yet strong polymer-based nanocomposites are highly desired for specific applications. However, the control of orientation and dispersion of reinforcing nanoparticles and the optimization of the interfacial interaction still pose substantial challenges in nanocellulose-reinforced polymer composites. In this study, poly(ethylene glycol) (PEG)-grafted cellulose nanofibers have demonstrated much better dispersion in a poly(lactic acid) (PLA) matrix as compared to unmodified nanocellulose. Through a uniaxial drawing method, aligned PLA/nanocellulose nanocomposites with high strength, high toughness, and unique optical behavior can be obtained. With the incorporation of 0.1 wt % of the PEG-grafted cellulose nanofibers in PLA, the ultimate strength of the aligned nanocomposite reaches 343 MPa, which is significantly higher than that of other aligned PLA-based nanocomposites reported previously. Moreover, its ultimate strength and toughness are enhanced by 39% and 70%, respectively, as compared to the aligned nanocomposite reinforced with unmodified cellulose nanofibers. In addition, the aligned nanocomposite film is highly transparent and possesses an anisotropic light scattering effect, revealing its significant potential for optical applications.


Assuntos
Celulose/química , Nanocompostos/química , Nanofibras/química , Poliésteres/química , Polietilenoglicóis/química , Polímeros/química , Difusão Dinâmica da Luz , Resistência à Tração
14.
Biomacromolecules ; 19(7): 2423-2431, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29620880

RESUMO

Although research on nanopaper structures from cellulose nanofibrils (CNFs) is well established, the mechanical behavior is not well understood, especially not when CNF is combined with hard nanoparticles. Cationic CNF (Q-CNF) was prepared and successfully decorated by anionic nanodiamond (ND) nanoparticles in hydrocolloidal form. The Q-CNF/ND nanocomposites were filtered from a hydrocolloid and dried. Unlike many other carbon nanocomposites, the Q-CNF/ND nanocomposites were optically transparent. Reinforcement effects from the nanodiamond were remarkable, such as Young's modulus (9.8 → 16.6 GPa) and tensile strength (209.5 → 277.5 MPa) at a content of only 1.9% v/v of ND, and the reinforcement mechanisms are discussed. Strong effects on CNF network deformation mechanisms were revealed by loading-unloading experiments. Scratch hardness also increased strongly with increased addition of ND.


Assuntos
Celulose/química , Nanodiamantes/química , Nanofibras/química , Coloides/química , Módulo de Elasticidade , Resistência à Tração
15.
Int Ophthalmol ; 38(2): 697-703, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28444523

RESUMO

PURPOSE: To compare the postoperative intraocular pressure (IOP) of eyes following pars plana vitrectomy (PPV) combined with intravitreal silicone oil (SO) tamponade by Corneal Visualization Scheimpflug Technology (CST), Goldmann applanation tonometry (GAT) and non-contact tonometry (NCT). METHODS: Thirty-eight participants who had undergone PPV combined with SO tamponade to treat vitreoretinal diseases were enrolled. Postoperative IOP measurements were obtained using CST, NCT and GAT. Inter-device agreement was assessed by Bland-Altman analysis. The correlation coefficient was used to describe the potential postoperative factors affecting the postoperative IOP differences between each device. RESULTS: Bland-Altman analysis revealed the bias between CST and GAT, between CST and NCT, and between GAT and NCT to be -0.2, 2.1 and 2.4 mmHg, respectively. CST and GAT correlated well with each other. NCT values were lower than those of GAT and CST (all p < 0.05), whereas CST values did not differ from the GAT readings. Central corneal thickness, corneal biomechanical properties and age showed significant correlation with the differences of CST-NCT and GAT-NCT. CONCLUSIONS: In SO tamponade eyes, NCT obtains lower IOP than other tonometry techniques, and CST is highly consistent with GAT. CST offers an optional non-contact method for measuring postoperative IOP in SO tamponade eyes.


Assuntos
Pressão Intraocular , Hipertensão Ocular/diagnóstico , Óleos de Silicone/efeitos adversos , Tonometria Ocular/instrumentação , Adulto , Idoso , Tamponamento Interno/efeitos adversos , Tamponamento Interno/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hipertensão Ocular/etiologia , Óleos de Silicone/administração & dosagem , Vitrectomia/efeitos adversos , Vitrectomia/métodos
16.
J Oral Pathol Med ; 46(5): 398-404, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27766688

RESUMO

OBJECTIVE: To evaluate microarchitectural changes in condylar cartilage and associated subchondral bone after bisphosphonates treatment using an ovariectomized (OVX) osteoporosis rat model. METHODS: Thirty six-month-old female Sprague-Dawley rats were randomly divided into sham, OVX, and risedronate (RIS)-treated groups. Both OVX and RIS groups received bilateral ovariectomy. OVX group was treated subcutaneously with saline, whereas RIS group received risedronate treatment (2.4 µg/kg) subcutaneously for 3 months. At the end of 3 months, animals were sacrificed and the entire condyles were harvested for micro-CT and histological analyses. Immunohistochemistry (IHC) was performed to assess the expression of type I/II collagen protein by semiquantitative imaging analysis. RESULTS: Micro-CT analysis showed OVX group had significant condylar subchondral bone loss compared to sham as shown by significant decrease in bone volume fraction (P = 0.028), trabecular thickness (P = 0.041), and significant increase in trabecular spacing (P = 0.003). In RIS group, partial inhibition of OVX-induced bone loss was detected. HE staining showed proliferative layer of condylar cartilage reduced, while hypertrophic chondrocyte layer increased significantly in RIS group compared to sham and OVX groups. IHC showed reduced expression of Col I in both the OVX and RIS groups, whereas expression of Col II was reduced in the OVX group but increased in the RIS group. CONCLUSION: Our findings suggest that systemic bisphosphonate treatment influences the structure and ossification of condylar cartilage and it has a dual action on condyle in a postmenopausal osteoporosis rat model which raises the concerns for the potential side effects of BPs on condyle to elder patients.


Assuntos
Difosfonatos/efeitos adversos , Côndilo Mandibular/efeitos dos fármacos , Osteoporose/patologia , Animais , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/diagnóstico por imagem , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/patologia , Feminino , Côndilo Mandibular/diagnóstico por imagem , Côndilo Mandibular/patologia , Osteoporose/diagnóstico por imagem , Ovariectomia , Ratos , Ratos Sprague-Dawley , Ácido Risedrônico/efeitos adversos , Microtomografia por Raio-X
17.
Water Sci Technol ; 76(7-8): 1939-1949, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29068326

RESUMO

Swine manure wastewater was treated in an anaerobic membrane bioreactor (AnMBR) that combined a continuous stirred tank reactor (CSTR) and a hollow-fiber ultrafiltration membrane, and the feasibility of ammonia and phosphorus recovery in the permeate was investigated. The AnMBR system was operated steadily with a high mixed liquor suspended solids (MLSS) concentration of 32.32 ± 6.24 g/L for 120 days, achieving an average methane yield of 280 mL/gVSadded and total chemical oxygen demand removal efficiency of 96%. The methane yield of the AnMBR is 83% higher than that of the single CSTR. The membrane fouling mechanism was examined, and MLSS and the polysaccharide contents of the extracellular polymeric substances were found to be the direct causes of membrane fouling. The effects of the permeation/relaxation rate and physical, chemical cleaning on membrane fouling were assessed for membrane fouling control, and results showed that a decrease in the permeation/relaxation rate together with chemical cleaning effectively reduced membrane fouling. In addition, a crystallization process was used for ammonia and phosphorus recovery from the permeate, and pH 9 was the optimal condition for struvite formation. The study has an instructive significance to the industrial applications of AnMBRs in treating high strength wastewater with nutrient recovery.


Assuntos
Reatores Biológicos , Carbono/química , Esterco , Nitrogênio/química , Suínos , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Animais , Análise da Demanda Biológica de Oxigênio , Membranas Artificiais , Metano/química , Fósforo/química , Águas Residuárias/química
18.
J Environ Sci (China) ; 48: 200-208, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27745665

RESUMO

Alkaline treatment with steel slag and NaOH addition were investigated under different pH conditions for the fermentation of waste activated sludge. Better performance was achieved in steel slag addition scenarios for both sludge hydrolysis and acidification. More solubilization of organic matters and much production of higher VFA (volatile fatty acid) in a shorter time can be achieved at pH10 when adjusted by steel slag. Higher enzyme activities were also observed in steel slag addition scenarios under the same pH conditions. Phosphorus concentration in the supernatant increased with fermentation time and pH in NaOH addition scenarios, while in contrast most phosphorus was released and captured by steel slag simultaneously in steel slag addition scenarios. These results suggest that steel slag can be used as a substitute for NaOH in sludge alkaline treatment.


Assuntos
Eliminação de Resíduos/métodos , Aço , Resíduos/análise , Ácidos Graxos Voláteis/química , Fermentação , Concentração de Íons de Hidrogênio , Hidrólise , Fósforo , Hidróxido de Sódio/química
19.
Biomacromolecules ; 16(12): 3916-24, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26505077

RESUMO

In this work, the problem to disperse cellulose nanocrystals (CNC) in hydrophobic polymer matrices has been addressed through application of an environmentally friendly chemical modification approach inspired by clay chemistry. The objective is to compare the effects of unmodified CNC and modified CNC (modCNC) reinforcement, where degree of CNC dispersion is of interest. Hydrophobic functionalization made it possible to disperse wood-based modCNC in organic solvent and cast well-dispersed nanocomposite films of poly(vinyl acetate) (PVAc) with 1-20 wt % CNC. Composite films were studied by infrared spectroscopy (FT-IR), UV-vis spectroscopy, dynamic mechanical thermal analysis (DMTA), tensile testing, and field-emission scanning electron microscopy (FE-SEM). Strongly increased mechanical properties were observed for modCNC nanocomposites. The reinforcement efficiency was much lower in unmodified CNC composites, and specific mechanisms causing the differences are discussed.


Assuntos
Celulose/química , Nanocompostos/química , Nanopartículas/química , Polivinil/química , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Nanocompostos/ultraestrutura , Nanopartículas/ultraestrutura , Propriedades de Superfície , Resistência à Tração
20.
Biomacromolecules ; 16(4): 1426-32, 2015 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-25738860

RESUMO

Multifunctional cellulose nanocrystals have been synthesized and applied as a new type of glyconanomaterial in lectin binding and bacterial imaging. The cellulose nanocrystals were prepared by TEMPO-mediated oxidation and acidic hydrolysis, followed by functionalization with a quinolone fluorophore and carbohydrate ligands. The cellulose nanocrystals were subsequently applied in interaction studies with carbohydrate-binding proteins and in bacterial imaging. The results show that the functional cellulose nanocrystals could selectively recognize the corresponding cognate lectins. In addition, mannosylated nanocrystals were shown to selectively interact with FimH-presenting E. coli, as detected by TEM and confocal fluorescence microscopy. These glyconanomaterials provide a new application of cellulose nanocrystals in biorecognition and imaging.


Assuntos
Celulose/química , Escherichia coli/ultraestrutura , Lectinas/metabolismo , Nanofibras/química , Nanopartículas/química , Microscopia Eletrônica de Transmissão/métodos , Ligação Proteica
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