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1.
Soft Matter ; 20(1): 192-200, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38073481

RESUMEN

Biofilms are initially formed by substances such as proteins secreted by bacteria adhering to a surface. To achieve a durable antibacterial material, biodegradable dihydroxyl-terminated poly[(ethylene oxide)-co-(ethylene carbonate)] (PEOC(OH)2) with anti-protein adsorption properties was synthesized in this study. Further polycondensation of PEOC(OH)2 and isophorone diisocyanate (IPDI) led to biodegradable polyurethane (PEOC-PU) with PEOC as the soft segment. For comparison, polyurethanes with polyethylene glycol (PEG-PU) and polypropylene glycol (PPG-PU) as soft segments were also synthesized. The chemical structures of the polyurethanes were characterized by 1H NMR and FTIR. The biodegradation behavior of PEOC-PU promoted by lipase due to the presence of ethylene carbonate units was also studied. Their resistance to proteins was studied using quartz crystal microbalance with dissipation (QCM-D) and the results revealed that PEOC-PU exhibited excellent nonspecific resistance to proteins. The colonization of microorganisms on PU in the liquid culture medium was further examined and the results showed that PEOC-PU exhibited excellent antibacterial adhesion performance due to its protein resistance and biodegradation.


Asunto(s)
Poliuretanos , Proteínas , Poliuretanos/química , Adsorción , Polietilenglicoles/química , Antibacterianos , Materiales Biocompatibles/química
2.
Dent Traumatol ; 38(5): 367-373, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35605156

RESUMEN

BACKGROUND/AIMS: Pediatric oral and maxillofacial surgeons have faced severe challenges in ward management due to their high risk of exposure during the COVID-19 epidemic. The aim of this study was to analyze and summarize the treatment methods and infection prevention and control measures applied in emergency cases in the Department of Pediatric Oral and Maxillofacial Surgery, Children's Hospital of Chongqing Medical University, during the COVID-19 epidemic. METHODS: In this retrospective study, information was collected from 256 pediatric emergency patients who were treated from January 23, 2020 to August 9, 2021. The patients' data were statistically analyzed according to age, gender, disease and pathogenesis, operation time, and the main treatment applied in pediatric oral and maxillofacial emergency cases during the COVID-19 epidemic. RESULTS: During the epidemic period, 256 pediatric emergency patients were successfully treated. Among them, there were 170 boys and 86 girls. In all, 182 patients were diagnosed with oral or facial lacerations; 43 had jaw fractures; 26 had maxillofacial infections; and five had dento-alveolar fractures. A total of 246 patients underwent surgery under negative pressure with level 3 protection standards. No doctors or patients infected with COVID-19 were found throughout the stury period. CONCLUSIONS: Pediatric oral and maxillofacial emergency in-patients mainly experienced maxillofacial trauma during the COVID-19 epidemic, followed by infection. Effective diagnosis and treatment, and avoidance of COVID-19 infection can be achieved by strictly following epidemic prevention and treatment procedures.


Asunto(s)
COVID-19 , Traumatismos Maxilofaciales , Fracturas Craneales , Niño , Brotes de Enfermedades , Femenino , Humanos , Masculino , Traumatismos Maxilofaciales/epidemiología , Traumatismos Maxilofaciales/terapia , Estudios Retrospectivos , Fracturas Craneales/epidemiología
3.
Biomacromolecules ; 22(5): 2033-2042, 2021 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-33880924

RESUMEN

Efficient enzymatic hydrolysis of cellulose in lignocellulose to glucose is one of the most critical steps for the production of biofuels. The nonproductive adsorption of lignin to expensive cellulase highly impedes the development of biorefinery. Understanding the lignin-cellulase interaction mechanism serves as a vital basis for reducing such nonproductive adsorption in their practical applications. Yet, limited report is available on the direct characterization of the lignin-cellulase interactions. Herein, for the first time, the nanomechanics of the biomacromolecules including lignin, cellulase, and cellulose were systematically investigated by using a surface force apparatus (SFA) at the nanoscale in aqueous solutions. Interestingly, a cation-π interaction was discovered and demonstrated between lignin and cellulase molecules through SFA measurements with the addition of different cations (Na+, K+, etc.). The complementary adsorption tests and theoretical calculations further confirmed the validity of the force measurement results. This finding further inspired the investigation of the interaction between lignin and other noncatalytic-hydrolysis protein (i.e., soy protein). Soy protein was demonstrated as an effective, biocompatible, and inexpensive lignin-blocker based on the molecular force measurements through the combined effects of electrostatic, cation-π, and hydrophobic interactions, which significantly improved the enzymatic hydrolysis efficiencies of cellulose in pretreated lignocellulosic substrates. Our results offer quantitative information on the fundamental understanding of the lignin-cellulase interaction mechanism. Such unraveled nanomechanics provides new insights into the development of advanced biotechnologies for addressing the nonproductive adsorption of lignin to cellulase, with great implications on improving the economics of lignocellulosic biorefinery.


Asunto(s)
Celulasa , Adsorción , Celulosa , Hidrólisis , Lignina
4.
Macromol Rapid Commun ; 42(14): e2100186, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33987942

RESUMEN

This study reports for the first time the excellent nonvolatile and volatile digital memory characteristics of polymers bearing 2-pyrrolidone and succinimide moieties. A series of new polymers is synthesized from poly(ethylene-alt-maleic anhydride) and four alcohol derivatives with and without 2-pyrrolidone and succinimide moieties. All polymers, including polyvinylpyrrolidone, are found to be thermally stable up to 195 °C or higher, and characterized regarding their molecular orbital energy levels, bandgap, and resistive digital memory behaviors. Excitingly, the polymers bearing either 2-pyrrolidone or succinimide moiety demonstrate p-type digital memory behaviors with high ON/OFF current ratios and long reliabilities. Nonvolatile digital memory performance is achieved over the film thickness range of 10-80 nm, whereas volatile digital memory is demonstrated over a much narrower range of film thickness. All digital memory performances can be originated from the 2-pyrrolidone and succinimide moieties possessing high affinity and stabilization power to charges via charge traps and transformations based on a hopping conduction process. Hence, these new polymers are suitable for the production of high-performance p-type nonvolatile and volatile digital memory devices. Moreover, 2-pyrrolidone and succinimide can be used as new and economical electroactive building blocks for the development of advanced digital memory materials.


Asunto(s)
Polímeros , Pirrolidinonas , Succinimidas
5.
Langmuir ; 34(38): 11593-11601, 2018 09 25.
Artículo en Inglés | MEDLINE | ID: mdl-30156852

RESUMEN

A bioinspired zwitterionic polyelectrolyte coating with excellent hydration ability has been regarded as a promising lubricating candidate for modifying artificial joint cartilage surface. In physiological fluids, the ubiquitous proteins play an important role in achieving outstanding boundary lubrication; however, a comprehensive understanding of the hydration lubrication between polyelectrolyte coatings and proteins still remains unclear. In this work, a facile fabrication of ultrasmooth polyelectrolyte coatings was developed via codeposition of synthesized poly(dopamine methacrylamide- co-2-methacryloyloxyethyl phosphorylcholine) (P(DMA- co-MPC)) and dopamine (DA) in a mild condition. Upon optimization of the feeding ratio of P(DMA- co-MPC) and DA, the as-fabricated PDA/P(DMA- co-MPC) coatings exhibit excellent lubricating properties when sliding with each other (friction coefficient µ = 0.036 ± 0.002, ∼2.8 MPa), as well as sliding with a model protein (bovine serum albumin (BSA)) layer (µ = 0.041 ± 0.005, ∼4.8 MPa) in phosphate-buffered saline (PBS, pH 7.4). Intriguingly, the lubrication in both systems shows Amontons-like behaviors: the friction is directly proportional to the applied load but independent of the shear velocity. Moreover, the PDA/P(DMA- co-MPC) coatings could resist the protein fouling (i.e., BSA) in PBS, which is crucial to prevent the surfaces from being contaminated when applied in biological media, thus maintaining their lubricating properties. Our results provide a versatile approach for facilely fabricating polyelectrolyte coatings with superior lubrication properties to both polyelectrolyte coatings and protein surfaces, with useful implications into the development of novel lubricating coatings for bioengineering applications (e.g., artificial joints).


Asunto(s)
Materiales Biomiméticos/química , Indoles/química , Lubricantes/química , Fosforilcolina/análogos & derivados , Polielectrolitos/química , Polímeros/química , Ácidos Polimetacrílicos/química , Animales , Incrustaciones Biológicas/prevención & control , Materiales Biomiméticos/síntesis química , Bovinos , Fricción , Indoles/síntesis química , Lubricantes/síntesis química , Lubrificación , Fosforilcolina/síntesis química , Fosforilcolina/química , Polielectrolitos/síntesis química , Polímeros/síntesis química , Ácidos Polimetacrílicos/síntesis química , Albúmina Sérica Bovina/química , Humectabilidad
6.
J Stomatol Oral Maxillofac Surg ; : 102032, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39233053

RESUMEN

BACKGROUND: The imaging manifestations of oral and maxillofacial myofibroma/myofibromatosis can vary among patients. Although many clinical cases have been reported, a consensus on the clinicopathological features of and treatment principles for this disease is lacking. PURPOSE: This study aimed to summarize the clinicopathological features of solitary myofibroma of the oral and maxillofacial regions in pediatric patients. METHODS: The clinical data, histological features, and immunohistochemical characteristics of ten pediatric patients who underwent surgical removal and subsequent pathological diagnosis of myofibroma were collected and retrospectively and cross-sectionally analyzed. RESULTS: Seven patients were male, and 3 were female, with ages ranging from 3 months to 6 years (mean: 2.6 years). The patients presented with solitary lesions involving the mandibular gingiva and adjacent mandible (4 patients), mandible (2 patients), oral floor and submandibular area and adjacent mandible (1 patient), gingiva (1 patient), maxilla (1 patient), and oropharynx (1 patient). Light microscopy revealed spindle-shaped tumor cells organized in bundles or vortex patterns, forming a hemangiopericytoma-like perivascular pattern, whereas immunohistochemical staining revealed diffuse smooth muscle actin (SMA) positivity. All patients underwent surgical resection, and none experienced recurrence over the 12- to 82-month follow-up. CONCLUSIONS: Solitary myofibroma in the oral and maxillofacial regions is predominantly observed in infants and young children, with a higher incidence among males. The prognosis is favorable following localized lesion resection or curettage of jawbone lesions. Accurate recognition of the clinical, radiological, and pathological features of the disease will reduce the misdiagnosis rate.

7.
ACS Appl Mater Interfaces ; 15(1): 2030-2042, 2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36571106

RESUMEN

As the central cellular player in fibrogenesis, activated hepatic stellate cells (aHSCs) are the major target of antifibrotic nanomedicines. Based on our finding that activated HSCs increase the expression of folate receptor alpha (FRα), we tried to apply folic acid (FA) decoration to generate an active drug-targeting at aHSCs and suppress hepato-fibrogenesis. FA-conjugated poly(ethylene glycol)-poly(ε-caprolactone) copolymers (PEG-PCL) were synthesized and self-assembled into the spherical micelles that owned a uniform size distribution averaging at 60 nm, excellent hemo- and cyto-compatibility, and pH-sensitive stability. These FA-modified micelles were preferentially ingested by aHSCs as expected and accumulated more in acutely CCl4 injured mouse livers compared to nondecorated counterparts. Such an aHSC targetability facilitated the loaded medicinal camptothecin (CPT) to achieve a greater therapeutic efficacy and inhibition of MF phenotypic genes in aHSCs. Encouragingly, though free CPT and nontargeting CPT micelles produced negligible curative outcomes, FA-decorated CPT micelles yielded effectively remedial effects in chronically CCl4-induced fibrotic mice, as represented by a significant shrinkage of aHSC population, suppression of fibrogenesis, and recovery of liver structure and function, clearly indicating the success of the folate decoration-supported aHSC-targeted strategy for antifibrotic nanomedicines in fibrosis resolution.


Asunto(s)
Ácido Fólico , Micelas , Ratones , Animales , Ácido Fólico/química , Células Estrelladas Hepáticas , Sistemas de Liberación de Medicamentos , Polietilenglicoles/química , Camptotecina/farmacología , Camptotecina/química , Portadores de Fármacos
8.
Adv Mater ; 35(6): e2208824, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36367362

RESUMEN

Implantable medical devices have been widely applied in diagnostics, therapeutics, organ restoration, and other biomedical areas, but often suffer from dysfunction and infections due to irreversible biofouling. Inspired by the self-defensive "vine-thorn" structure of climbing thorny plants, a zwitterion-conjugated protein is engineered via grafting sulfobetaine methacrylate (SBMA) segments on native bovine serum albumin (BSA) protein molecules for surface coating and antifouling applications in complex biological fluids. Unlike traditional synthetic polymers of which the coating operation requires arduous surface pretreatments, the engineered protein BSA@PSBMA (PolySBMA conjugated BSA) can achieve facile and surface-independent coating on various substrates through a simple dipping/spraying method. Interfacial molecular force measurements and adsorption tests demonstrate that the substrate-foulant attraction is significantly suppressed due to strong interfacial hydration and steric repulsion of the bionic structure of BSA@PSBMA, enabling coating surfaces to exhibit superior resistance to biofouling for a broad spectrum of species including proteins, metabolites, cells, and biofluids under various biological conditions. This work provides an innovative paradigm of using native proteins to generate engineered proteins with extraordinary antifouling capability and desired surface properties for bioengineering applications.


Asunto(s)
Incrustaciones Biológicas , Incrustaciones Biológicas/prevención & control , Biónica , Polímeros/química , Propiedades de Superficie , Albúmina Sérica Bovina/química , Adsorción
9.
Int J Radiat Oncol Biol Phys ; 117(4): 914-924, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37356553

RESUMEN

PURPOSE: The objective of this study was to estimate the long-term survival, late toxicity profile, and quality of life of patients with locoregionally advanced nasopharyngeal carcinoma (NPC) treated with combined induction chemotherapy (IC) and concurrent chemoradiotherapy from a clinical trial focused on reducing the target volume of intensity modulated radiation therapy (IMRT). METHODS AND MATERIALS: This prospective, randomized clinical trial was conducted across 6 Chinese hospitals and included 212 patients with stage III-IVB NPC who were randomly allocated to a pre-IC or post-IC group. Eligible patients were treated with 2 cycles of IC + CCRT. All patients underwent radical IMRT. Gross tumor volumes of the nasopharynx were delineated according to pre-IC and post-IC tumor extent in the pre-IC and post-IC groups, respectively. RESULTS: After a median follow-up of 98.4 months, 32 of 97 (32.9%) and 33 of 115 (28.7%) patients experienced treatment failure or died in the pre-IC and post-IC groups, respectively. None of the patients developed grade 4 late toxicity. Late radiation-induced toxicity predominantly manifested as grade 1 to 2 subcutaneous fibrosis, hearing loss, tinnitus, and xerostomia, whereas grade 3 late toxicity included xerostomia and hearing loss. The 5-year estimated overall, progression-free, locoregional recurrence-free, and distant metastasis-free survival rates in the pre-IC and post-IC groups were 78.2% versus 83.3%, 72.0% versus 78.1%, 90.2% versus 93.5%, and 78.1% versus 82.1%, respectively. The pre-IC group had a significantly higher incidence of xerostomia and hearing damage than the post-IC group. In terms of quality of life, compared with the pre-IC group, the post-IC group showed significant improvement in cognitive function (P = .045) and symptoms including dry mouth (P = .004), sticky saliva (P = .047), and feeling ill (P = .041). CONCLUSIONS: After long-term follow-up, we confirmed that reducing the target volumes of IMRT after IC in locoregionally advanced NPC showed no inferiority in terms of the risk of locoregional relapse and potentially improved quality of life and alleviated late toxicity.


Asunto(s)
Pérdida Auditiva , Neoplasias Nasofaríngeas , Traumatismos por Radiación , Radioterapia de Intensidad Modulada , Xerostomía , Humanos , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Cisplatino , Pérdida Auditiva/etiología , Quimioterapia de Inducción/efectos adversos , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Estudios Prospectivos , Calidad de Vida , Traumatismos por Radiación/etiología , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Xerostomía/etiología
10.
Artículo en Inglés | MEDLINE | ID: mdl-35206336

RESUMEN

Iron-rich rolling sludge (FeRS) represents a kind of typical solid waste produced in the iron and steel industry, containing a certain amount of oil and large amounts of iron-dominant minerals. Pyrolysis under anaerobic environment can effectively eliminate organics at high temperatures without oxidation of Fe. This paper firstly investigated comprehensively the pyrolysis characteristics of FeRS. The degradation of organics in FeRS mainly occurred before 400 °C. The activation energy for pyrolysis of FeRS was extremely low, ca. 5.44 kJ/mol. The effects of pyrolytic temperature, atmosphere, heating rate, and stirring on pyrolysis characteristics were conducted. Commonly, the yield of solid residues maintained around 85 wt.%, with approximately 13 wt.% oil and 2 wt.% gas. Due to the low yield of oil and gas, their further utilization remains difficult despite CO2 introduction which could upgrade their quality. The solid residues after pyrolysis exhibited porous properties with co-existence of micropores and mesopores. Combined with the high content of zero-valent iron, magnetic property, hydrophobic characteristic, and low density, the solid residues could be further utilized for water pollution control and soil remediation. Moreover, the solid residues were suitable for sintering to recover valuable iron resources. However, the solid residues also contained certain heavy metals, such as Cd, Cr, Cu, Ni, Pb, and Zn, which might cause secondary pollution during their utilization. In particular, the toxic Cr possessed high content, which should be treated with detoxification and removal. This paper provides fundamental information for pyrolysis of FeRS and utilization of solid residues.


Asunto(s)
Metales Pesados , Pirólisis , Hierro , Metales Pesados/química , Aguas del Alcantarillado/química , Acero
11.
Sci Total Environ ; 806(Pt 1): 150213, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34571232

RESUMEN

Tissue-nonspecific alkaline phosphatase (ALPL) and alpha-amylase (AMY) are essential in the immune and digestive systems, respectively. Microplastics (MPs) pose a risk to zooplankton which may be in a state of feeding, starvation, or subsequent refeeding. However, molecular characterization of both enzymes and the regulated mechanisms affected by nutritional statuses and MPs remain unclear in zooplankton. In the present study, four full-length genes encoding ALPL and two genes encoding AMY were cloned and characterized from an isolated marine rotifer, Brachionus rotundiformis, including alplA, alplB, alplC, alplD, amy2a, and amy2al. AMY activity and expression of amy2a and amy2al were reduced by starvation and recovered after refeeding compared with feeding. ALPL activity remained unchanged among different statuses, while alplA, alplB and alplD were down-regulated by starvation and refeeding compared with feeding. ALPL activity was not affected by exposure to 10, 100 and 1000 µg/L MPs in rotifers subjected to feeding, starvation and refeeding, whereas AMY activity was significantly enhanced by 1000 µg/L MPs in rotifers subjected to refeeding. Gene expression of the tested genes, except amy2a, was significantly responsive to MPs, especially in the feeding rotifers, depending on MPs concentrations and nutritional statuses. Two-way ANOVA confirmed that these changes were strongly associated with the interaction between MPs concentrations and nutritional statuses. The present study is the first to demonstrate a nutritional status-dependent impact of MPs on immune and digestive responses, and provides more sensitive molecular biomarkers for assessing MPs toxicity using the species as model animals.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Fosfatasa Alcalina , Animales , Estado Nutricional , Plásticos , Contaminantes Químicos del Agua/toxicidad , alfa-Amilasas
12.
Aquat Toxicol ; 243: 106055, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34954476

RESUMEN

Microplastics (MPs) pollution has attracted worldwide attention. Superoxide dismutase (SOD) is a sensitive indicator for assessing the toxic effects of MPs in aquatic organisms. However, few studies have been performed to identify all genes encoding SOD in aquatic invertebrates. Especially, effects of MPs on SOD activity and expression in aquatic organisms under starvation or a subsequent refeeding status are unclear. In the present study, all full-length genes encoding SOD were cloned and characterized from the marine rotifer Brachionus rotundiformis, including CuZnSOD1, CuZnSOD2, CuZnSOD3, CuZnSOD4, CuZnSOD5, MnSOD1, and MnSOD2. The CuZnSOD1, CuZnSOD2 and MnSOD2 are homologous to SODs from vertebrates and the other SOD proteins are rotifer-specific according to the results from the phylogenetic tree. The conserved signature sequences and binding sites of Cu2+, Zn2+and Mn2+ were also identified in the seven SOD proteins. Compared with feeding, starvation down-regulated SOD activity and mRNA expression of CuZnSOD2, CuZnSOD4, CuZnSOD5, MnSOD1 and MnSOD2 while refeeding maintained SOD activity comparable to the feeding level and up-regulated CuZnSOD5 and MnSOD2. Intake of MPs by B. rotundiformis was observed by examining fluorescence signals from the fluorescently-labeled microplastics under different nutritional status. Exposure to MPs reduced rotifer density and increased malondialdehyde (MDA) content and SOD activity in the rotifers under the refeeding condition, but did not affect these indicators under the feeding and starvation conditions. However, mRNA expression of some tested genes was responsive to MPs in the fed, starved and refed rotifers. The present study for the first time demonstrated a nutritional status-dependent effect of MPs on oxidative stress response, and provided more sensitive molecular biomarkers for assessing the toxicity of MPs using B. rotundiformis as a model animal.


Asunto(s)
Rotíferos , Contaminantes Químicos del Agua , Animales , Microplásticos , Estado Nutricional , Filogenia , Plásticos , Rotíferos/genética , Superóxido Dismutasa/genética , Contaminantes Químicos del Agua/toxicidad
13.
Nat Commun ; 12(1): 3613, 2021 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-34127656

RESUMEN

The development of biomedical glues is an important, yet challenging task as seemingly mutually exclusive properties need to be combined in one material, i.e. strong adhesion and adaption to remodeling processes in healing tissue. Here, we report a biocompatible and biodegradable protein-based adhesive with high adhesion strengths. The maximum strength reaches 16.5 ± 2.2 MPa on hard substrates, which is comparable to that of commercial cyanoacrylate superglue and higher than other protein-based adhesives by at least one order of magnitude. Moreover, the strong adhesion on soft tissues qualifies the adhesive as biomedical glue outperforming some commercial products. Robust mechanical properties are realized without covalent bond formation during the adhesion process. A complex consisting of cationic supercharged polypeptides and anionic aromatic surfactants with lysine to surfactant molar ratio of 1:0.9 is driven by multiple supramolecular interactions enabling such strong adhesion. We demonstrate the glue's robust performance in vitro and in vivo for cosmetic and hemostasis applications and accelerated wound healing by comparison to surgical wound closures.


Asunto(s)
Péptidos/química , Péptidos/genética , Proteínas/química , Proteínas/genética , Adhesivos/química , Adulto , Animales , Cianoacrilatos/química , Modelos Animales de Enfermedad , Femenino , Regeneración Tisular Dirigida/métodos , Hemostasis , Humanos , Hígado/patología , Ratones , Ratas , Ratas Wistar , Piel/patología , Porcinos , Adhesivos Tisulares/química , Cicatrización de Heridas
14.
Int J Biol Macromol ; 152: 1002-1009, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31751695

RESUMEN

Hydroxypropyl methylcellulose (HPMC)/sodium citrate (SC)/lipid tea polyphenol (LTP) photophobic films with different pore sizes from micron scale to nanometer scale were prepared by regulating the SC content (1-7%). The microstructures, physical and sustained antioxidant properties of these films were studied by using wide angel X-ray diffraction, small angle X-ray scattering (SAXS), scanning electron microscope, whiteness meter, ultraviolet spectrophotometer, texture analyzer and peroxide value test. Composite films with higher SC content showed larger pore size and whiteness. With the increasing SC content, crystallinity first increased then decreased. The addition of SC decreased the Ds (surface fractal dimension) value, smoothness of the cross-section structure, tensile strength, elongation and modulus of composite films. HPMC/SC/LTP microporous films possessed control-release property in oil system, reflected by the lowest peroxide value of peanut oil enclosed in film with 3% SC during three weeks, meaning this film showed the best sustained antioxidant property.


Asunto(s)
Antioxidantes/química , Antioxidantes/farmacología , Derivados de la Hipromelosa/química , Derivados de la Hipromelosa/farmacología , Luz , Fenómenos Mecánicos , Porosidad
15.
J Arthroplasty ; 24(4): 543-8, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18534409

RESUMEN

The aim of the study is to explore the impact of storage time on wear rates. Two groups of acetabular liners with a storage time of 1 and 4 years were tested on 2 hip simulators of the same type. There were 6 liners in each group. Gravimetric analysis was performed every 500 000 cycles for a total of 3 million cycles. The mean wear rate for the group of 4-year-old liners (36.3 mg/million cycles) was significantly higher than that for the 1-year-old group (23.1 mg/million cycles) (P < .05). After the last gravimetric analysis, scanning electron microscopy was used to observe the wear patterns of the bearing surfaces. This study found that wear resistance decreased as storage time increased.


Asunto(s)
Artroplastia de Reemplazo de Cadera/instrumentación , Prótesis de Cadera/normas , Ensayo de Materiales/métodos , Polietileno , Falla de Prótesis , Acetábulo , Análisis de Falla de Equipo , Humanos , Microscopía Electrónica de Rastreo , Factores de Tiempo
16.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(5): 505-508, 2019 Oct 01.
Artículo en Zh | MEDLINE | ID: mdl-31721498

RESUMEN

OBJECTIVE: To study the clinical features and treatments of congenital submandibular duct dilatation. METHODS: Seven children with congenital submandibular duct dilatation from January 2008 to March 2018 were included in this study, whose average age was 5 months and 22 days. The clinical manifestations are unilateral swelling of the mouth floor. All seven children underwent sublingual gland resection, submandibular gland dilatation catheter resection, and catheter reroute under general anesthesia. Intraoperatively, the orifice of the submandibular gland was constricted and part of the catheter was dilated. RESULTS: All seven patients had good healing without swelling or cyst formation. CONCLUSIONS: Congenital submandibular duct dilatation occurs at a young age. Early diagnosis and treatment can help prevent further expansion of the catheter and avoid gland atrophy, feeding difficulty, and breathing obstruction. Simultaneous excision of the sublingual gland can avoid the formation of postoperative sublingual cyst.


Asunto(s)
Ránula , Conductos Salivales , Niño , Dilatación , Humanos , Lactante , Glándula Sublingual , Glándula Submandibular
17.
Int J Mol Med ; 40(5): 1602-1610, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28901385

RESUMEN

The aim of the present study was to assess the effectiveness of Rhizoma Dioscoreae extract (RDE) on preventing rat alveolar bone loss induced by ovariectomy (OVX), and to determine the role of interleukin-6 (IL-6)/signal transducer and activator of transcription 3 (STAT3) signaling pathway in this effect. Female Wistar rats were subjected to OVX or sham surgery. The rats that had undergone OVX were treated with RDE (RDE group), vehicle (OVX group) or 17ß-estradiol subcutaneous injection (E2 group). Subsequently, bone metabolic activity was assessed by analyzing 3-D alveolar bone construction, bone mineral density, as well as the plasma biomarkers of bone turnover. The gene expression of alveolar bone in the OVX and RDE groups was evaluated by IL-6/STAT3 signaling pathway polymerase chain reaction (PCR) arrays, and differentially expressed genes were determined through reverse transcription-quantitative PCR. The inhibitory effect of RDE on alveolar bone loss in the OVX group was demonstrated in the study. In comparison with the OVX group, the RDE group exhibited 19 downregulated genes and 1 upregulated gene associated with the IL-6/STAT3 signaling pathway in alveolar bone. Thus, RDE was shown to relieve OVX-induced alveolar bone loss in rats, an effect which was likely associated with decreased abnormal bone remodeling via regulation of the IL-6/STAT3 signaling pathway.


Asunto(s)
Pérdida de Hueso Alveolar/etiología , Pérdida de Hueso Alveolar/metabolismo , Araceae/química , Interleucina-6/metabolismo , Extractos Vegetales/farmacología , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/efectos de los fármacos , Pérdida de Hueso Alveolar/diagnóstico , Pérdida de Hueso Alveolar/tratamiento farmacológico , Animales , Biomarcadores , Peso Corporal/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Expresión Génica , Perfilación de la Expresión Génica , Tamaño de los Órganos/efectos de los fármacos , Ovariectomía/efectos adversos , Extractos Vegetales/química , Ratas , Transcriptoma , Microtomografía por Rayos X
18.
Artículo en Inglés | MEDLINE | ID: mdl-26439523

RESUMEN

As complicated mixture systems, active components of Chuanxiong Rhizoma are very difficult to identify and discriminate. In this paper, the macroscopic IR fingerprint method including Fourier transform infrared spectroscopy (FT-IR), the second derivative infrared spectroscopy (SD-IR) and two-dimensional correlation infrared spectroscopy (2DCOS-IR), was applied to study and identify Chuanxiong raw materials and its different segmented production of HPD-100 macroporous resin. Chuanxiong Rhizoma is rich in sucrose. In the FT-IR spectra, water eluate is more similar to sucrose than the powder and the decoction. Their second derivative spectra amplified the differences and revealed the potentially characteristic IR absorption bands and combined with the correlation coefficient, concluding that 50% ethanol eluate had more ligustilide than other eluates. Finally, it can be found from 2DCOS-IR spectra that proteins were extracted by ethanol from Chuanxiong decoction by HPD-100 macroporous resin. It was demonstrated that the above three-step infrared spectroscopy could be applicable for quick, non-destructive and effective analysis and identification of very complicated and similar mixture systems of traditional Chinese medicines.


Asunto(s)
Medicamentos Herbarios Chinos/análisis , Espectroscopía Infrarroja por Transformada de Fourier/métodos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/análisis , Porosidad , Resinas Sintéticas/química , Sacarosa/análisis
19.
Mol Med Rep ; 13(6): 5342-8, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27122061

RESUMEN

Rhizoma Dioscoreae extract (RDE) exhibits a protective effect on alveolar bone loss in ovariectomized (OVX) rats. The aim of this study was to predict the pathways or targets that are regulated by RDE, by re­assessing our previously reported data and conducting a protein­protein interaction (PPI) network analysis. In total, 383 differentially expressed genes (≥3­fold) between alveolar bone samples from the RDE and OVX group rats were identified, and a PPI network was constructed based on these genes. Furthermore, four molecular clusters (A­D) in the PPI network with the smallest P­values were detected by molecular complex detection (MCODE) algorithm. Using Database for Annotation, Visualization and Integrated Discovery (DAVID) and Ingenuity Pathway Analysis (IPA) tools, two molecular clusters (A and B) were enriched for biological process in Gene Ontology (GO). Only cluster A was associated with biological pathways in the IPA database. GO and pathway analysis results showed that cluster A, associated with cell cycle regulation, was the most important molecular cluster in the PPI network. In addition, cyclin­dependent kinase 1 (CDK1) may be a key molecule achieving the cell­cycle­regulatory function of cluster A. From the PPI network analysis, it was predicted that delayed cell cycle progression in excessive alveolar bone remodeling via downregulation of CDK1 may be another mechanism underling the anti­osteopenic effect of RDE on alveolar bone.


Asunto(s)
Pérdida de Hueso Alveolar/tratamiento farmacológico , Pérdida de Hueso Alveolar/metabolismo , Ciclo Celular/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Pinellia/química , Extractos Vegetales/farmacología , Pérdida de Hueso Alveolar/patología , Animales , Femenino , Extractos Vegetales/química , Ratas
20.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 48(1): 23-6, 2013 Jan.
Artículo en Zh | MEDLINE | ID: mdl-23534517

RESUMEN

OBJECTIVE: To observe the peri-implant osseointegration after the application of exogenous nerve growth factor (NGF)-gelatin sponge (GS) composite. METHODS: Six beagle dogs were used to establish bi-mandible simultaneous implant model after the first and second premolar extraction. Then the dental implants were implanted into the distal socket while the bone defect was made in the mesial socket of each mandible. Then the NGF-GS was implanted into the defects as NGF-GS group, the gelatin sponge alone was implanted as GS control and the control group was left empty. Two dogs were sacrificed each time at 4 weeks, 8 weeks and 12 weeks postoperatively. Specimens were subjected to general observation, radiography, bone histological and histomorphometric analysis for the new bone formation. The data were analyzed with SPSS 11.5 software package. RESULTS: The bone density in the defects around implants at 4 and 8 weeks postoperatively was lower than the normal bone. The bone-implant contact ratio in the NGF-GS group [(57.7 ± 6.4)%] was significantly higher than that in the GS control group and the control group [the ratio were (44.2 ± 3.3)% and (31.2 ± 3.1)%] (P < 0.01) at 4 weeks postoperatively, the bone-implant contact ratio in the GS control group was also significantly higher than that in the control group (P < 0.01) at that time. The bone-implant contact ratio in the NGF-GS group [(94.8 ± 7.7)%] was slightly higher than that in the GS control group and the control group [the ratio were (83.0 ± 4.1)% and (86.4 ± 6.3)%] at 8 weeks postoperatively, but there was no statistical difference (P > 0.05). The bone density in the defects around implants at 12 weeks was almost the same as the normal bone, there was no difference of the bone-implant contact ratio. CONCLUSIONS: NGF-GS application could increase new bone formation, accelerate maturation of trabecular bone around the implants and shorten the period of osseointegration.


Asunto(s)
Implantación Dental Endoósea/métodos , Esponja de Gelatina Absorbible/uso terapéutico , Factor de Crecimiento Nervioso/uso terapéutico , Animales , Implantes Dentales , Perros , Masculino
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