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1.
Anal Chem ; 94(33): 11500-11507, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35943850

RESUMO

The development of new technologies for the separation, selection, and isolation of microparticles such as rare target cells, circulating tumor cells, cancer stem cells, and immune cells has become increasingly important in the last few years. Microparticle separation technologies are usually applied to the analysis of disease-associated cells, but these procedures often face a cell separation problem that is often insufficient for single specific cell analyses. To overcome these limitations, a highly accurate size-based microparticle separation technique, herein called "rotating magnetic chromatography", is proposed in this work. Magnetic nanoparticles, placed in a microfluidic separation channel, are forced to move in well-defined trajectories by an external magnetic field, colliding with microparticles that are in this way separated on the basis of their dimensions with high accuracy and reproducibility. The method was optimized by using fluorescein isothiocyanate-modified polystyrene particles (chosen as a reference standard) and then applied to the analysis of cancer cells like Hep-3B and SK-Hep-1, allowing their fast and high-resolution chromatographic separation as a function of their dimensions. Due to its unmatched sub-micrometer cell separation capabilities, RMC can be considered a break-through technique that can unlock new perspectives in different scientific fields, that is, in medical oncology.


Assuntos
Cromatografia , Magnetismo , Separação Celular , Fenômenos Magnéticos , Poliestirenos/química , Reprodutibilidade dos Testes
2.
J Virol ; 91(13)2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28424289

RESUMO

Coxsackievirus A16 (CV-A16), CV-A6, and enterovirus D68 (EV-D68) belong to the Picornaviridae family and are major causes of hand, foot, and mouth disease (HFMD) and pediatric respiratory disease worldwide. The biological characteristics of these viruses, especially their interplay with the host innate immune system, have not been well investigated. In this study, we discovered that the 3Cpro proteins from CV-A16, CV-A6, and EV-D68 bind melanoma differentiation-associated gene 5 (MDA5) and inhibit its interaction with MAVS. Consequently, MDA5-triggered type I interferon (IFN) signaling in the retinoic acid-inducible gene I-like receptor (RLR) pathway was blocked by the CV-A16, CV-A6, and EV-D68 3Cpro proteins. Furthermore, the CV-A16, CV-A6, and EV-D68 3Cpro proteins all cleave transforming growth factor ß-activated kinase 1 (TAK1), resulting in the inhibition of NF-κB activation, a host response also critical for Toll-like receptor (TLR)-mediated signaling. Thus, our data demonstrate that circulating HFMD-associated CV-A16 and CV-A6, as well as severe respiratory disease-associated EV-D68, have developed novel mechanisms to subvert host innate immune responses by targeting key factors in the RLR and TLR pathways. Blocking the ability of 3Cpro proteins from diverse enteroviruses and coxsackieviruses to interfere with type I IFN induction should restore IFN antiviral function, offering a potential novel antiviral strategy.IMPORTANCE CV-A16, CV-A6, and EV-D68 are emerging pathogens associated with hand, foot, and mouth disease and pediatric respiratory disease worldwide. The pathogenic mechanisms of these viruses are largely unknown. Here we demonstrate that the CV-A16, CV-A6, and EV-D68 3Cpro proteins block MDA5-triggered type I IFN induction. The 3Cpro proteins of these viruses bind MDA5 and inhibit its interaction with MAVS. In addition, the CV-A16, CV-A6, and EV-D68 3Cpro proteins cleave TAK1 to inhibit the NF-κB response. Thus, our data demonstrate that circulating HFMD-associated CV-A16 and CV-A6, as well as severe respiratory disease-associated EV-D68, have developed a mechanism to subvert host innate immune responses by simultaneously targeting key factors in the RLR and TLR pathways. These findings indicate the potential merit of targeting the CV-A16, CV-A6, and EV-D68 3Cpro proteins as an antiviral strategy.


Assuntos
Cisteína Endopeptidases/metabolismo , Enterovirus/imunologia , Enterovirus/patogenicidade , Interações Hospedeiro-Patógeno , Evasão da Resposta Imune , Imunidade Inata , Helicase IFIH1 Induzida por Interferon/antagonistas & inibidores , Proteínas Virais/metabolismo , Proteases Virais 3C , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Proteólise , Transdução de Sinais
3.
Br J Clin Pharmacol ; 79(4): 650-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25297637

RESUMO

AIMS: The aims of the study were to assess the pharmacokinetics, pharmacodynamics, safety and tolerability of a novel, pegylated recombinant human consensus interferon-α variant (PEG-IFN-SA) in healthy volunteers. A pharmacokinetic and pharmacodynamic comparison of PEG-IFN-SA and peginterferon-α-2a in healthy subjects was evaluated. METHODS: A randomized, dose-escalating, single administration dose phase I clinical study was conducted. Thirty healthy subjects received PEG-IFN-SA as a single dose of 0.5-2.0 µg kg(-1) by subcutaneous (s.c.) injection in four parallel groups. Eight subjects received peginterferon-α-2a as a single dose of 180 µg s.c. RESULTS: The incidence rates of adverse events for PEG-IFN-SA and peginterferon-α-2a were 29 of 30 and 7 of 8, respectively. The adverse events for PEG-IFN-SA were mild to moderate and similar to those of peginterferon-α-2a. Within 168 h after injection, the mean values of maximal concentration and area under the plasma concentration-time curve from time of dosing to 168 h [AUC(0-168h) ] for 2',5'-oligoadenylate, neopterin and ß2 -microglobulin for PEG-IFN-SA at 1.5 µg kg(-1 ) s.c. were similar to or higher than those for peginterferon-α-2a at a dose of 180 µg s.c. After s.c. injection of PEG-IFN-SA at 1.5 µg kg(-1) , the mean geometric mean values of plasma half-life, time to maximal concentration, maximal concentration and AUC(0-168h) were 55.3 h, 26.9 h, 0.53 µg l(-1) and 44.0 µg l(-1) h, respectively. CONCLUSIONS: The tolerance, pharmacokinetic and pharmacodynamic characteristics of PEG-IFN-SA support its administration by s.c. injection as a single dose of 1.5 µg kg(-1) or at 2.0 µg kg(-1) per week.


Assuntos
Antivirais/farmacologia , Antivirais/farmacocinética , Interferon-alfa/farmacologia , Interferon-alfa/farmacocinética , Polietilenoglicóis/farmacologia , Polietilenoglicóis/farmacocinética , Nucleotídeos de Adenina/sangue , Nucleotídeos de Adenina/imunologia , Adolescente , Adulto , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Voluntários Saudáveis , Humanos , Injeções Subcutâneas , Interferon-alfa/administração & dosagem , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Neopterina/sangue , Neopterina/imunologia , Oligorribonucleotídeos/sangue , Oligorribonucleotídeos/imunologia , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/farmacologia , Adulto Jovem
4.
Environ Pollut ; 346: 123554, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38395130

RESUMO

In the past few decades, mercury (Hg) discharged into the coastal bays of China has significantly increased; however, long-term trends regarding the pollution status and sources of Hg in these bays have yet to be clear. Focusing on this issue, surface sediments and core sediments were collected in the Jiaozhou Bay (JZB), a typical bay highly affected by human activities in China, to analyze the concentrations and stable isotopic composition of Hg. Total mercury (THg) concentrations in surface sediment varied from 7 to 163 ng/g, with higher levels located in the eastern JZB, possibly attributed to intensive industrial and population density. THg in sediment cores 14 and 20 displayed fluctuating increasing trends from 1936 to 2019, reflecting the deterioration of Hg pollution. In contrast, THg in sediment core 28 near the river mouth exhibited a declining trend, possibly due to the river dam construction. Using a stable isotope mixing model, contributions of various sources (atmospheric, riverine, and industrial emissions) to Hg in the JZB were estimated. The results showed that industrial emissions were the main source (over 50%) of mercury in the JZB in 2019. Sediment cores recorded an increase in industrial Hg due to early industrialization and Reform and Opening-up before 2000. In addition, sediment core 20 demonstrated a rise in the percentage of riverine Hg due to land reclamation at the bay's mouth during 2000-2007.


Assuntos
Mercúrio , Poluentes Químicos da Água , Humanos , Mercúrio/análise , Baías , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos , Isótopos , China
5.
Colloids Surf B Biointerfaces ; 222: 113061, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36508890

RESUMO

Articular cartilage is essential for normal daily joint function activities. However, it is difficult for articular cartilage to repair itself after injury due to the lack of nerves and blood vessels, so an effective cartilage repair method is necessary. As a three-dimensional polymer network structure with high water content, hydrogel is a good candidate material for cartilage repair, and it is also a research hotspot in the treatment of cartilage injury. Here, a porous dual-crosslinked hydrogel containing sodium alginate (SA) and silk sericin (SS) was designed for in situ repair of cartilage damage. The degradation rate of the hydrogel was regulated by changing the content of SS to match the rate of cartilage regeneration. The hydrogel had excellent mechanical properties (compressive strength≈245 kPa, compressibility≈60%), high water content (85%-88%) and porosity(>20%), and when the content of SS is 1%, the scaffold has the best comprehensive performance. Existing excellent cytocompatibility, the scaffold can promote the adhesion and proliferation of chondrocytes while reducing inflammatory cell infiltration. The cartilage defect repair experiments in vivo showed that artificial cartilage was formed at 4 weeks with molecular structure similar to natural cartilage. It is expected to be applied to clinical cartilage repair through the dual-crosslinked three-dimensional cartilage scaffold.


Assuntos
Cartilagem Articular , Sericinas , Hidrogéis/química , Sericinas/farmacologia , Sericinas/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/metabolismo , Condrócitos/metabolismo , Água/metabolismo , Engenharia Tecidual , Alicerces Teciduais
6.
J Hazard Mater ; 455: 131597, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37182462

RESUMO

Riverine mercury (Hg) is the largest global source of Hg in coastal oceans. The Yellow River delivers the majority of Hg to the semi-enclosed Bohai Sea, where Hg contamination adversely affects the surrounding heavily populated provinces in northern China. Mercury distribution patterns in the river-estuary interacting area provides essential information to understand the riverine Hg transport and biogeochemical cycling of Hg in the estuary. Analyzing the spatial distributions of total- (THg) and methyl-Hg (MeHg) in the lower end of Yellow River (∼105 km) and adjacent estuary, we found the dominant role of suspended particulate matter (SPM) in Hg transport, with 99.1% and 86.3% of THg and MeHg being in particulate phase. The SPM dynamics, such as transport, retention, sorting and sedimentation, governs Hg transport with water flow and particle-water partition of Hg. While THg decreased along the water flow to the river mouth with the settlement of particulate THg (about 27.5% onto the riverbed and the rest entering the sea), MeHg and particulate MeHg increased by 110% and 117%, respectively. This study highlights the distinct patterns in THg and MeHg distribution and transport and suggests potential Hg methylation and external MeHg input in the river-estuary mixed zone.

7.
PeerJ ; 11: e15757, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37601264

RESUMO

The objective of this study was to investigate the cellulose degradation rate (CDR) and lignin degradation rate (LDR) of Codonopsis pilosula straw (CPS) and the optimal fermentation parameters for mixed fungal fermentation. Single-factor tests were used to study the effects of the fungal ratio (Trichoderma reesei: Coprinus comatus), fungal inoculum, corn flour content, and fermentation time on the degradation rate of cellulose and lignin. Based on the results of this experiment, the optimal fermentation factors were identified, and the effects of various factors and their interactions on the degradation rates of cellulose and lignin were further evaluated using the response surface method. The quadratic polynomial mathematical model of degradation rates of the cellulose and lignin in CPS by mixed fungus fermentation was established using Design Expert software v8.0.6. Under the optimal parameters for fungal fermentation of CPS straw (fungal ratio 4:6, fungal inoculum 8%, corn flour content 10%, fermentation time of 15 d), the CDR and LDR reached 13.65% and 10.73%, respectively. Collectively, the mixed fungal fermentation of CPS resulted in decreased lignin and cellulose content, better retention of nutrients, and enhanced fermentation quality. The results of this study indicate that fermentation using Trichoderma reesei and Coprinus comatus is a productive method for straw degradation, providing a theoretical basis for the development of CPS as feed.


Assuntos
Codonopsis , Lignina , Fermentação , Celulose , Amido
8.
Front Pharmacol ; 14: 1272744, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026958

RESUMO

Background: Until now, there have been no randomized controlled trials directly evaluating the efficacy of high-dose ilaprazole-amoxicillin dual therapy (HT) in comparison to other standard treatments for H. pylori (Helicobacter pylori) infection. This study aimed to compare the effectiveness and safety of HT with bismuth quadruple therapy (BQT) as an initial treatment for H. pylori. Methods: This single-center, prospective, randomized clinical controlled trial recruited 225 consecutive patients. They were assigned to either HT group (ilaprazole, 10 mg, twice daily; amoxicillin 1,000 mg, three times daily) or BQT group (compound bismuth aluminate granules, 2.6 g, three times daily; ilaprazole, 5 mg, twice daily; amoxicillin, 1,000 mg, twice daily; clarithromycin, 500 mg, twice daily) for 14 days. The 13C-urea breath test assessed eradication success 4 weeks after treatment. The primary outcome focused on the eradication rate, with secondary outcomes including safety and compliance. Results: From February 2023 to March 2023, 228 subjects were screened, and 225 were randomized. The HT and BQT groups showed eradication rates of 76.3% and 61.3% (p = 0.015) both by intention-to-treat (ITT) analysis and per-protocol (PP) analysis. HT was associated with fewer adverse events than BQT (27.2% vs. 81.8%, p = 0.002). The most commonly reported adverse events was bitter taste of mouth (3.5% vs. 60.4%, p < 0.001). There was no significant difference in compliance between the two groups (89.5% vs. 92.8%, p = 0.264). Conclusion: The 14-day HT treatment demonstrates better efficacy in H. pylori eradication treatment and improved safety and compliance compared to BQT. The results provide supporting evidence for 14-day HT can be potentially considered as a first-line regimen for empirical treatment. Clinical Trial Registration: https://www.chictr.org.cn/showproj.html?proj=186562, identifier ChiCTR2200066284.

9.
J Sep Sci ; 34(21): 3083-91, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21972216

RESUMO

A novel magnetic material Fe(3)O(4)/SiO(2)/P(MAA-co-VBC-co-DVB) was prepared via the hypercrosslinking of its precursor which was produced via precipitation polymerization of methacrylic acid (MAA), vinylbenzyl chloride (VBC), and divinylbenzene (DVB) in the presence of Fe(3)O(4)/SiO(2) submicrospheres with the surface containing abundant reactive double bonds. The resultant sorbent was characterized by scan electron microscopy, N(2) adsorption, and Fourier transform infrared spectroscopy. It was found that this material had remarkable features such as large surface area (500 m(2)/g) and pore volume (0.32 cm(3)/g), as well as desirable chemical composition (including hydrophobic and ion-exchange moieties). Taking advantages of the Fe(3)O(4)/SiO(2)/P(MAA-co-VBC-co-DVB), a magnetic SPE (MSPE) coupled with capillary electrophoresis (CE) method was developed for the determination of illegal drugs in urine samples. The extraction time could be clearly shortened up to 3 min. The recoveries of these drug compounds were in the range of 84.0-123% with relative standard deviations ranging between 1.7 and 10.5%; the limit of detection was in the range of 4.0-6.0 µg/L. The proposed method is simple, effective, and low-cost, and provides an accurate and sensitive detection platform for abused drug analysis.


Assuntos
Anfetaminas/urina , Reagentes de Ligações Cruzadas/química , Ketamina/urina , Fenômenos Magnéticos , Polímeros/química , Extração em Fase Sólida , Transtornos Relacionados ao Uso de Substâncias/urina , Reagentes de Ligações Cruzadas/síntese química , Humanos , Magnetismo , Valores de Referência , Transtornos Relacionados ao Uso de Substâncias/diagnóstico
11.
Yao Xue Xue Bao ; 44(5): 506-9, 2009 May.
Artigo em Zh | MEDLINE | ID: mdl-19618727

RESUMO

To study the pharmacokinetics of rhGH decorated by polyethylene glycol (PEG-rhGH) after sc administration in rat, serum PEG-rhGH concentrations were measured by 125I labeled method after sc in rat, the pharmacokinetic model and parameters were fitted and calculated by the 3P97 program. After sc injection at doses of 150, 300, and 600 microg x kg(-1) in rat, the serum PEG-rhGH concentration-time curves were fitted to a one-compartment model. The rhGH decorated by polyethylene glycol could prolong the action duration of rhGH in vivo, and reach the goal of long-action.


Assuntos
Hormônio do Crescimento Humano/farmacocinética , Polietilenoglicóis/química , Animais , Área Sob a Curva , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Feminino , Hormônio do Crescimento Humano/administração & dosagem , Hormônio do Crescimento Humano/sangue , Injeções Subcutâneas , Masculino , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/sangue , Proteínas Recombinantes/farmacocinética
12.
ChemSusChem ; 11(5): 843-847, 2018 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-29417754

RESUMO

A simple, clean, and efficient method has been developed for generating hydroxyl radicals on a nitrocellulose membrane (NCM) under light of wavelengths greater than 280 nm. Hydroxyl radicals formed on the NCM surface, diffusing into the bulk solution under irradiation. Radical generation was shown to be dependent on the nature of the NCM and light, and independent of the properties of the bulk solution. The quantum yield for hydroxyl radicals from the NCM was 1.72×10-4 , which is approximately 2.46 times that from TiO2 . This hydroxyl radical generation method was preliminarily applied in the photodegradation of organic pollutants, in which electrostatic interactions between the pollutant molecules and the NCM surface were found to play a key role. Further applications of this hydroxyl radical generation method should be assessed.


Assuntos
Recuperação e Remediação Ambiental/métodos , Radical Hidroxila/síntese química , Compostos Orgânicos/química , Processos Fotoquímicos , Fotólise , Colódio , Luz , Membranas Artificiais , Compostos Orgânicos/efeitos da radiação , Eletricidade Estática , Poluentes Químicos da Água/química
13.
Nanoscale ; 10(1): 184-194, 2017 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-29210401

RESUMO

Image-guided drug delivery is an emerging strategy in the field of nanomedicine. The addition of image guidance to a traditional drug delivery system is expected to achieve highly efficient treatment by tracking the drug carriers in the body and monitoring their effective accumulation in the targeted tissues. In this study, we developed multifunctional magneto-plasmonic liposomes (MPLs), a hybrid system combining liposomes and magneto-plasmonic nanoparticles for a triple-modality image-guided drug delivery. Tenofovir disoproxil fumarate, an antiretroviral drug used to treat human immunodeficiency virus type 1 (HIV-1), was encapsulated into the MPLs to enable the treatment in the brain microenvironment, which is inaccessible to most of the drugs. We found strong negative and positive contrasts originating from the magnetic core of MPLs in magnetic resonance imaging (MRI) and magnetic particle imaging (MPI), respectively. The gold shell of MPLs showed bright positive contrast in X-ray computed tomography (CT). MPLs achieved enhanced transmigration across an in vitro blood-brain barrier (BBB) model by magnetic targeting. Moreover, MPLs provided desired therapeutic effects against HIV infected microglia cells.


Assuntos
Encéfalo/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Infecções por HIV/diagnóstico por imagem , Infecções por HIV/tratamento farmacológico , Lipossomos , Antirretrovirais/administração & dosagem , Barreira Hematoencefálica , Linhagem Celular , Ouro , Humanos , Magnetismo , Nanopartículas Metálicas , Microglia/efeitos dos fármacos , Microglia/virologia , Imagem Multimodal , Nanomedicina , Tenofovir/administração & dosagem
14.
Chemosphere ; 156: 14-20, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27156211

RESUMO

Laboratory experiments suggest that polymeric Cr(III) could exist in aqueous solution for a relative long period of time. However, the occurrence of polymeric Cr(III) has not been reported in environmental media due partially to the lack of method for speciating polymeric Cr. We observed an unknown Cr species during the course of study on speciation of Cr in the leachates of chromated-copper-arsenate (CCA)-treated wood. Efforts were made to identify structure of the unknown Cr species. Considering the forms of Cr existed in the CCA-treated woods, we mainly focused our efforts to determine if the unknown species were polymeric Cr(III), complex of Cr/As or complex of Cr with dissolved organic matter (DOM). In order to evaluate whether polymeric Cr(III) largely exist in wood leachates, high performance liquid chromatography coupled with inductively coupled mass spectrometry (HPLC-ICPMS was used) for simultaneous speciation of monomeric Cr(III), polymeric Cr(III), and Cr(VI). In addition to wood leachates where polymeric Cr (III) ranged from 39.1 to 67.4%, occurrence of the unknown Cr species in other environmental matrices, including surface waters, tap and waste waters, was also investigated. It was found that polymeric Cr(III) could exist in environmental samples containing µg/L level of Cr, at a level up to 60% of total Cr, suggesting that polymeric Cr(III) could significantly exist in natural environments. Failure in quantifying polymeric Cr(III) would lead to the underestimation of total Cr and bias in Cr speciation. The environmental implication of the presence of polymeric Cr(III) species in the environment deserves further study.


Assuntos
Arseniatos/química , Carcinógenos Ambientais/análise , Cromo/análise , Madeira/química , Carcinógenos Ambientais/química , Cromatografia Líquida de Alta Pressão/métodos , Cromo/química , Monitoramento Ambiental , Espectrometria de Massas/métodos , Polímeros/análise , Polímeros/química
15.
Technol Health Care ; 23(3): 299-305, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25669206

RESUMO

BACKGROUND: The objective of this study was to investigate how treatment strategies in the same treatment affected the canine's initial displacement and the stress in periodontal ligament using three-dimensional finite element analysis. And to find out the way to design an effective treatment plan. METHODS: Based on computed tomography images of the teeth and their supporting tissues, solid models were used to build finite element models. Three treatment plans of three different transparent tooth correction therapies finite element-analyses were operated. RESULTS: The canine's initial displacement and stresses' distribution in periodontal ligament were obtained. CONCLUSIONS: For rotation movement, the canine should rotate along tooth long axis, and not combine with other kinds of tooth movement as possible. For translation movement, the combination of translation and inclination movement is helpful for the treatment.


Assuntos
Análise de Elementos Finitos/estatística & dados numéricos , Ortodontia/estatística & dados numéricos , Fenômenos Biomecânicos , Simulação por Computador , Humanos , Incisivo/metabolismo , Modelos Biológicos , Ligamento Periodontal/metabolismo , Estresse Mecânico , Técnicas de Movimentação Dentária/estatística & dados numéricos
16.
Medicine (Baltimore) ; 94(45): e1974, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26559274

RESUMO

Schwannoma comprises a group of nerve sheath tumors. Morphologic variants of schwannoma have no distinct relationship to clinical behavior, but unawareness of rare variants may lead to diagnostic pitfall and risk of mistreatment. Microcystic/reticular schwannoma is a recently described rare variant of schwannoma. We report a case of a 61-year-old female with a 5.0 cm × 3.5 cm × 3.0 cm mass in the right mandible, which has never been reported to date. Light microscopic evaluation showed that the mass was circumscribed with focal infiltration. Arranged in a prominent microcystic and reticular growth pattern, tumor cells were spindle-shaped with eosinophilic cytoplasm. No evidence of cytologic atypia, mitosis, or necrosis was observed. The stroma of the tumor mainly contained myxoid material with local infiltration of hyalinized collagen. Tumor cells showed diffuse and strong nuclear and cytoplasmic immunoreactivity for S100 protein. Tumor cells were also positive for CD34, CD99, and NSE, but negative for CK, EMA, CK5/6, P63, Calponin, CD10, SMA, Desmin, GFAP, NF, Syn, and CgA. The proliferation marker MIB-1 showed <1% nuclear reaction. Furthermore, we reviewed the clinical and pathological features of 24 previously reported cases of microcystic/reticular schwannoma. Unlike classic schwannoma, the reticular variant showed striking microcystic and reticular architecture microscopically. Recognition of these distinct entities is essential in avoiding misdiagnosis. Unlike classic schwannoma with a complete capsule, some masses were reported to lack encapsulation or contain focal infiltration. Further follow-up of tentative or identified cases is necessary to better understand this schwannoma.


Assuntos
Mandíbula/patologia , Neoplasias Mandibulares/patologia , Neurilemoma/patologia , Feminino , Humanos , Pessoa de Meia-Idade
17.
Proc Inst Mech Eng H ; 229(9): 619-28, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26163521

RESUMO

Surgical treatment is one of the effective methods of treatment in cervical spondylosis. The traditional method of operation is decompression fusion; however, this surgery results in restricted movement of cervical vertebra and adjacent segment degeneration. Due to the deficiency of traditional surgery, scholars have widely carried out artificial cervical disk replacement surgery and have achieved good clinical effects. Comparing to the characteristics of the common artificial cervical disk which is used frequently, we developed a new artificial cervical intervertebral disk prosthesis. The purpose of this study was to determine the wear behavior in a cervical total disk replacement system. The total disk replacement system tested consists of a ultra-high-molecular-weight polyethylene inlay articulating between a Ti6Al4V alloy superior plate and an inferior plate, using a spine wear simulator, per the ISO 18192-1:2011 standard test methods. Three rotations and axial force were applied on each station. The specimens were removed at 5 × 10(5) and 10(6) cycles and at intervals of 10(6) cycles thereafter to determine the actual mass loss. The serum was replaced every 5 × 10(5) cycles. The specimens were changed periodically among the different stations. A mean ultrahigh molecular weight polyethylene inlay wear rate of 0.53 mg per million cycles (standard = 0.13 mg per 10(6) cycles) was found after 10(7) cycles. All inferior plates showed slight scratching after 10(7) cycles. The impingement wear simulation introduced here proved to be suitable to predict in vivo impingement behavior in regard to the contact pattern seen on retrieved devices of the Pretic-I disk arthroplasty design in a preclinical test.


Assuntos
Vértebras Cervicais/fisiologia , Prótese Articular , Substituição Total de Disco , Adulto , Ligas , Fenômenos Biomecânicos/fisiologia , Análise de Falha de Equipamento , Humanos , Modelos Teóricos , Polietilenos , Desenho de Prótese , Titânio
18.
Acta Biomater ; 9(10): 8631-42, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23261923

RESUMO

Magnesium has attracted much attention as a class of biodegradable metallic biomaterials. In this study, a silicate electrolyte-based micro-arc oxidation (MAO) treatment was adopted to prepare forsterite-containing MAO coatings on a ZK60 magnesium alloy in order to decrease the degradation rate and increase the biological property of the alloy. Four anodization voltages were chosen to prepare the MAO coatings. The cell experiment showed a cytotoxicity of grade 0 for the MAO-coated alloy to L929 cells and the hemolytic ratio was dramatically decreased for the MAO-coated alloy compared with the bare one. The corrosion resistance and the degradation behavior of the MAO-coated ZK60 alloy were studied using drop tests, electrochemical measurements and immersion tests. The results indicate that the MAO coating could effectively decrease the initial degradation rate of the alloy. The corrosion resistance of MAO coating was increased with the elevation of the preparation voltage. A degradation model for ZK60 alloy with a forsterite-containing MAO coating was proposed. Based on the model, the MAO-coated alloy experiences destruction and restoration simultaneously, and the coating fails in a peeling-off mode.


Assuntos
Implantes Absorvíveis , Ligas/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Teste de Materiais , Compostos de Silício/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Corrosão , Técnicas Eletroquímicas , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Camundongos , Oxirredução , Soluções , Espectrometria por Raios X , Difração de Raios X
19.
Nan Fang Yi Ke Da Xue Xue Bao ; 30(11): 2581-2, 2010 Nov.
Artigo em Zh | MEDLINE | ID: mdl-21097439

RESUMO

OBJECTIVE: To investigate the influences of varying lingual traction forces on the space-closing speed in a typodont model. METHODS: Forty-two Angle Class I standard typodont models of bimaxillary teeth protrusion were divided into 7 equal groups. Four regions of the model were paired to groups, and in the odd-numbered models, the top left and bottom left regions served as the experimental group and the top right and bottom right regions as the control group; in the even-numbered models, the regions in the model were grouped oppositely. In the experimental group, the space was closed by niti wire extension spring in the buccal ridge combined with lingual elastic traction of 0, 5, 10, 15, 20, 25 and 30 g. In the control group, the space was closed by exclusive niti wire extension spring in the buccal ridge. The space-closing speed were analyzed in all the groups. RESULTS: The space-closing speed was significantly lower in the control group than in the experimental groups with lingual traction forces of 5, 10, 15, 20 and 25 g (P<0.05), but a traction force of 30 g resulted in a significantly lower speed than that in the control group (P<0.05). The space closing speed was the greatest in the experimental group with a traction force of 15 g (P<0.05). CONCLUSION: Niti wire extension spring in the buccal ridge combined with lingual elastic traction results in faster space-closing speed than traditional exclusive niti wire extension spring. The speed is the fastest by applying 15 g lingual traction, which is also associated with the lowest slip resistance.


Assuntos
Análise do Estresse Dentário , Modelos Dentários , Extração Dentária/métodos , Tração
20.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 26(5): 519-21, 2008 Oct.
Artigo em Zh | MEDLINE | ID: mdl-19007075

RESUMO

OBJECTIVE: To study the clinical effect of Gelatamp colloidal silver gelatin sponge on preventing the complication of teeth extraction. METHODS: 672 teeth were divided into experimental group and control group semi-randomly. All teeth were extracted after local anesthesia and sockets were cleaned. Gelatamp colloidal silver gelatin sponge was implanted into socket in experimental group and nothing was implanted into alveolar socket in control group. The complication of teeth extraction was observed on 0.5 h, 2 d and 7 d after extraction. The incidence rate of complication was calculated. RESULTS: The incidence rate of complication of teeth extraction in experimental group was 7.72%, which was lower than that of control group (24.43%). There was significant difference in the incidence rates of complication between experimental group and control group (P < 0.05). The incidence rate of bleeding, infection, pain, swelling and dry socket after teeth extraction in experimental group was lower than those of control group, and the difference between them was statistically significant (P < 0.05). CONCLUSION: The results demonstrate that Gelatamp colloidal silver gelatin sponge can prevent the occurrence of complication of teeth extraction, this can be used in clinic.


Assuntos
Gelatina , Prata , Animais , Alvéolo Seco , Humanos , Masculino , Poríferos , Extração Dentária
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