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1.
BMC Oral Health ; 23(1): 139, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36899301

RESUMO

BACKGROUND: Children's dental anxiety is common in dental clinics. This study aimed to determine the interrater agreement between children's self-reported and their mothers' proxy-reported dental anxiety and its affecting factors. METHODS: In this cross-sectional study performed in a dental clinic, primary school students and their mothers were assessed for enrollment eligibility. The Modified Dental Anxiety Scale plus Facial Image Scale (MDAS-FIS) was employed to test both the children's self-reported and their mothers' proxy-reported dental anxiety independently. The interrater agreement was analyzed using percentage agreement and the linear weighted kappa (k) coefficient. Factors affecting children's dental anxiety were analyzed using univariate and multivariate logistic regression models. RESULTS: One hundred children and their mothers were enrolled. The median ages of the children and mothers were 8.5 and 40.0 years old, respectively, and 38.0% (38/100) of the children were female. The scores of children's self-reported dental anxiety were significantly higher than their mothers' proxy-reported dental anxiety (MDAS-Questions 1-5, all p < 0.05); moreover, there was no agreement between the two groups in terms of all anxiety hierarchies (kappa coefficient = 0.028, p = 0.593). In the univariate model, a total of seven factors (age, gender, maternal anxiety, number of dental visits, mother's presence or absence, oral health status, and having siblings or not) were involved for analysis, and age [every 1-year increase, odds ratio (OR) = 0.661, 95% confidence interval (CI) = 0.514-0.850, p = 0.001], several dental visits (every 1 visit increase, OR = 0.409, 95% CI = 0.190-0.880, p = 0.022), and mother presence (OR = 0.286, 95% CI = 0.114-0.714, p = 0.007) were affecting factors. In the multivariate model, only age (every 1 year increase) and maternal presence were associated with 0.697-fold (95% CI = 0.535-0.908, p = 0.007) and 0.362-fold (95% CI = 0.135-0.967, p = 0.043) decreases in the risk of children's dental anxiety during dental visits and treatment, respectively. CONCLUSION: There was no significant agreement between elementary school students' self-reported dental anxiety and mothers' proxy ratings of children's dental anxiety, which suggests that self-reported dental anxiety by children should be encouraged and adopted, and the mother's presence during dental visits is strongly recommended.


Assuntos
Ansiedade ao Tratamento Odontológico , Mães , Adulto , Criança , Feminino , Humanos , Estudos Transversais , População do Leste Asiático , Autorrelato
2.
BMC Oral Health ; 18(1): 190, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30463548

RESUMO

BACKGROUND: Dental and periodontal tissue development is a complicated process involving a finely regulated network of communication among various cell types. Understanding the mechanisms involved in regulating dental mesenchymal stem cells (MSCs) and osteoclast cell differentiation is critical. However, it is still unclear whether histone deacetylase HDAC6 is involved in dental MSCs fate determination and osteoclast differentiation. METHODS: We used shRNA and siRNA knockdown to explore the role of HDAC6 in dental MSCs odontogenic differentiation and osteoclasts maturation. RESULTS: Based on HDAC6 knockdown dental MSCs, our data suggest that HDAC6 knockdown significantly increases alkaline phosphate activity and mineralized nodules formation. Additionally, mRNA expression of odontogenic marker genes (OSX, OCN, and OPN) was induced by HDAC6 knockdown. By using HDAC6 siRNA, we knocked down HDAC6 in osteoclast precursor RAW 264.7 cells. Our data suggests that HDAC6 knockdown significantly inhibited osteoclasts differentiation. Additionally, mRNA expression of osteoclast marker genes Trap, Mmp9, and Ctsk was decreased by HDAC6 knockdown. CONCLUSIONS: Our study demonstrated that HDAC6 plays an important role in regulating dental MSCs and osteoclasts differentiation.


Assuntos
Diferenciação Celular/fisiologia , Desacetilase 6 de Histona/fisiologia , Células-Tronco Mesenquimais/citologia , Osteoclastos/citologia , Adulto , Células Cultivadas , Polpa Dentária/citologia , Técnicas de Silenciamento de Genes , Vetores Genéticos , Desacetilase 6 de Histona/genética , Humanos , Lentivirus , RNA Interferente Pequeno/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transfecção
3.
Plant Physiol ; 158(1): 264-72, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22100644

RESUMO

Primexine deposition and plasma membrane undulation are the initial steps of pollen wall formation. However, little is known about the genes involved in this important biological process. Here, we report a novel gene, NO PRIMEXINE AND PLASMA MEMBRANE UNDULATION (NPU), which functions in the early stage of pollen wall development in Arabidopsis (Arabidopsis thaliana). Loss of NPU function causes male sterility due to a defect in callose synthesis and sporopollenin deposition, resulting in disrupted pollen in npu mutants. Transmission electronic microscopy observation demonstrated that primexine deposition and plasma membrane undulation are completely absent in the npu mutants. NPU encodes a membrane protein with two transmembrane domains and one intracellular domain. In situ hybridization analysis revealed that NPU is strongly expressed in microspores and the tapetum during the tetrad stage. All these results together indicate that NPU plays a vital role in primexine deposition and plasma membrane undulation during early pollen wall development.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Membrana Celular/metabolismo , Gametogênese Vegetal/genética , Proteínas de Membrana/metabolismo , Proteínas de Arabidopsis/genética , Biopolímeros , Carotenoides , Membrana Celular/genética , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Glucanos/biossíntese , Meiose , Proteínas de Membrana/genética , Mutação , Infertilidade das Plantas/genética , Pólen/genética , Pólen/crescimento & desenvolvimento , Pólen/metabolismo , Estrutura Terciária de Proteína
4.
Int J Biol Macromol ; 245: 125511, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37356693

RESUMO

Large bone defects have presented a significant challenge in orthopedic treatments, and the emergence of tissue-engineered scaffolds has introduced new avenues for treatment. Nonetheless, the clinical application of such scaffolds has been hindered by drawbacks like inadequate mechanical properties, and deficient osteogenesis. Herein, a biocompatible polylactic acid (PLA) based composite was proposed to emulate cancellous bone's morphology by incorporating nano-hydroxyapatite (nHA). In addition, a quantity of Mg2+ and chitosan (CS) as active osteogenic factors were adopted to imitate the bone marrow mesenchymal components in vivo. Using a pre-evaporated solvent and sacrificial multi-template techniques, the cellular PLA-based tissue engineering scaffolds containing macropores larger than 100 µm and micropores smaller than 10 µm were developed. The scaffold's bionic structure, osteogenic active component, and multi-scale cellular make it comparable to cancellous bone, with favorable mechanical properties and hydrophilicity. Vitro tests using Sprague-Dawley (SD) rat bone marrow mesenchymal stem cells (rBMSCs) demonstrated the scaffold's excellent biocompatibility to induce high efficiency of osteogenic differentiation. The bionic porous scaffold with multi-scale cellular structure also can recruit rBMSCs, promote bone regrowth and osteogenic differentiation, and facilitate the regeneration of defective bone tissue for repair. This contribution presented a promising strategy for future advancements in bone tissue engineering.


Assuntos
Biônica , Osteogênese , Ratos , Animais , Ratos Sprague-Dawley , Alicerces Teciduais/química , Osso e Ossos , Poliésteres/farmacologia , Poliésteres/química , Engenharia Tecidual/métodos , Diferenciação Celular , Regeneração Óssea
5.
Biochem Soc Trans ; 40(6): 1257-60, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23176464

RESUMO

The mineral-respiring bacterium Shewanella oneidensis uses a protein complex, MtrCAB, composed of two decahaem cytochromes brought together inside a transmembrane porin to transport electrons across the outer membrane to a variety of mineral-based electron acceptors. A proteoliposome system has been developed that contains Methyl Viologen as an internalized electron carrier and valinomycin as a membrane-associated cation exchanger. These proteoliposomes can be used as a model system to investigate MtrCAB function.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Lipossomos/química , Shewanella/metabolismo , Proteínas da Membrana Bacteriana Externa/fisiologia , Transporte de Elétrons , Modelos Biológicos , Oxirredução , Paraquat/química , Valinomicina
6.
J Mater Sci Mater Med ; 23(4): 1063-72, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22426652

RESUMO

Keratoprosthetic devices are subject to chronic inflammatory, pathological processes and the external environment that affect their stability and biocompatibility with the ocular surface and adjacent ocular tissues. We compared the corrosion resistance property and tissue-implant reaction of titanium oxide (TiO(2)) with hydroxyapatite (HA) in artificial tear fluid and a rabbit skin implantation model. The dissolution properties of the implant surfaces were evaluated with scanning electronic microscope (SEM) and atomic force microscope (AFM). Tissue inflammatory reactions were evaluated by Hematoxylin & Eosin staining, avidin biotin peroxidase complex (ABC) immunoassay and immunofluorescence. SEM and AFM images showed that there was less pitting corrosion on the surface of TiO(2) implants compared with HA. TiO(2) and HA exhibited a similar pattern of foreign body capsule formation and inflammatory cellular responses. The Collagen I/Collagen III ratio of the TiO(2) capsule was higher than that of the HA capsule. TiO(2) implants possess a high corrosion resistance property both in vitro and in vivo and the inflammatory cellular response to TiO(2) is similar to HA. With regards to corrosion resistance and inflammatory tissue responses, TiO(2) appears to be a promising material for keratoprosthetic skirt devices.


Assuntos
Materiais Biocompatíveis , Córnea , Durapatita/farmacologia , Próteses e Implantes , Titânio/farmacologia , Animais , Corrosão , Técnicas Eletroquímicas , Imuno-Histoquímica , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Coelhos
7.
Acta Biomater ; 140: 492-505, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34879292

RESUMO

Ferroptosis is a newly discovered non-apoptotic cell death form but its therapeutic efficacy triggered by traditional iron-based nanomaterials or classic drug inducers has been far from satisfactory due to the high glutathione (GSH) level in cancer cells and insufficient lipid peroxide production. Here we reported a ferroptosis/apoptosis combinational therapy by depleting GSH and downregulating GPX4 to disrupt redox homeostasis and amplify ferroptosis-related oxidation effect. In this study, we developed reactive oxygen species (ROS)-responsive serum-resistant nanoparticles with thioketal-crosslinked fluorinated polyethyleneimine 1.8K (TKPF) as the core, which were wrapped with hyaluronic acid (HA) as the shell (TKPFH NP) to co-deliver shGPX4 and shMTHFD2 plasmids for cancer treatment. The highly efficient and tumor-selective gene carrier TKPFH NPs revealed outstanding transfection efficiency (∼100 %) and sustained the efficiency (∼50 %) even in media containing 90 % FBS. Mediated by HA, TKPFH NPs actively targeted CD44 receptors, thus enabling efficient uptake by tumor cells and experiencing surface charge conversion to induce subsequent lysosomal escape. Then the TKPF NPs were effectively disintegrated by the abundant ROS in cancer cells, which facilitated the release of plasmids and avoided the cytotoxicity of cationic polymers. shGPX4 plasmid induced ferroptosis by producing ROS and lipid peroxides via downregulating GPX4, while shMTHFD2 triggered apoptosis by modulating NADPH/NADP and depleting GSH of the cancer cells. Moreover, GSH consumption caused by shMTHFD2 indirectly suppressed GPX4 and further augmented ferroptosis, showing synergistic anticancer effect against B16-F10 cells. Taken together, the rationally designed dual-gene loaded TKPFH NPs provided a safe and high-performance platform for enhanced ferroptosis-apoptosis combined anticancer efficacy based on gene therapy. STATEMENT OF SIGNIFICANCE: The therapeutic efficacy of ferroptosis has been far from satisfactory due to high GSH level and insufficient lipid peroxide production in cancer cells. Herein, we reported a ferroptosis/apoptosis combinational therapy by depleting GSH and downregulating GPX4 to disrupt redox homeostasis and amplify ferroptosis-related oxidation effect. ROS-responsive serum-resistant nanoparticles were fabricated with thioketal-crosslinked fluorinated PEI 1.8K (TKPF) as the core and hyaluronic acid (HA) as the shell (TKPFH NP) to co-deliver shGPX4 and shMTHFD2 plasmids. The shGPX4 plasmid induced ferroptosis by producing ROS and lipid peroxides via downregulating GPX4, while shMTHFD2 triggered apoptosis by modulating NADPH/NADP and depleting GSH. The rationally designed dual-gene loaded TKPFH NPs provided a safe and high-performance platform aimed for enhanced ferroptosis-apoptosis combined anticancer efficacy.


Assuntos
Ferroptose , Neoplasias , Apoptose , Linhagem Celular Tumoral , Plasmídeos , Polietilenoimina/farmacologia , Espécies Reativas de Oxigênio/metabolismo
8.
Anal Bioanal Chem ; 399(10): 3345-57, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20852850

RESUMO

In this review the focus is on application of porous monoliths to miniaturized extraction of biological analysis, with emphasis on porous monolithic materials and different miniaturized extraction formats. The general approaches used to synthesize organic polymer and silica monolithic materials are highlighted, and their properties and applicability are described and compared. Several extraction formats, including in-tube microextraction, chip-based microextraction, tip-based microextraction, among others, are reviewed in depth.


Assuntos
Polímeros/química , Dióxido de Silício/química , Microextração em Fase Sólida/instrumentação , Absorção , Polímeros/síntese química , Porosidade , Dióxido de Silício/síntese química
9.
BMC Musculoskelet Disord ; 12: 286, 2011 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-22188765

RESUMO

BACKGROUND: The operative treatment of adult degenerative scoliosis combined with osteoporosis increase following the epidemiological development. Studies have confirmed that screws in osteoporotic spines have significant lower-screw strength with more frequent screw movements within the vertebra than normal spines. Screws augmented with polymethylmethacrylate (PMMA) or with autogenous bone can offer more powerful corrective force and significant advantages. METHODS: A retrospective analysis was conducted on 31 consecutive patients with degenerative lumbar scoliosis combined with osteoporosis who had surgery from December 2000. All had a minimum of 2-year follow-up. All patients had posterior approach surgery. 14 of them were fixed with pedicle screw by augmentation with polymethylmethacrylate (PMMA) and the other 17 patients with autogenous bone. Age, sex and whether smoking were similar between the two groups. Surgical time, blood loss, blood transfusion, medical cost, post surgery ICU time, hospital day, length of oral pain medicines taken, Pre-and postoperative Oswestry disability index questionnaire and surgical revision were documented and compared. Preoperative, postoperative and final follow up Cobb angle, sagittal lumbar curve, correction rate, and Follow up Cobb loss were also compared. RESULTS: No significant differences were found between the autogenous bone group and polymethylmethacrylate group with regards to all the targets above except for length of oral pain medicines taken and surgery cost. 2 patients were seen leakage during operation, but there is neither damage of nerve nor symptom after operation. No revision was needed. CONCLUSION: Both augmentation pedicle screw with polymethylmethacrylate (PMMA) and autogenous bone treating degenerative lumbar scoliosis combined with osteoporosis can achieve a good surgical result. Less oral pain medicines taken are the potential benefits of polymethylmethacrylate augmentation, but that is at the cost of more medical spending.


Assuntos
Cimentos Ósseos/uso terapêutico , Parafusos Ósseos , Transplante Ósseo , Vértebras Lombares/cirurgia , Osteoporose/complicações , Polimetil Metacrilato/uso terapêutico , Escoliose/cirurgia , Fusão Vertebral/instrumentação , Absorciometria de Fóton , Adulto , Idoso , Cimentos Ósseos/efeitos adversos , Densidade Óssea , Transplante Ósseo/efeitos adversos , China , Avaliação da Deficiência , Desenho de Equipamento , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico , Polimetil Metacrilato/efeitos adversos , Estudos Retrospectivos , Escoliose/complicações , Escoliose/diagnóstico , Fusão Vertebral/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
10.
J Chromatogr A ; 1623: 461154, 2020 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-32505273

RESUMO

Chiral stationary phases (CSPs) have always been research hotspot in enantiomer separation. Currently, most of the CSPs are based on silica platform. In this research, monodisperse, porous glycidyl methacrylate-divinylbenzene copolymer particles (poly(GMA-DVB)) were designed and prepared. Then the GMA was further reacted with ethylenediamine to introduce amino groups onto the polymer, which provide anchoring sites for cellulose derivatives. Herein, Cellulose-tris (3,5-dimethylphenylcarbamate) (CDMPC) was successfully coated onto the polymer microspheres, achieving a stable and successful CSP. The porous structure and the surface moieties of the CSPs were studied in detail. The chromatographic separation was optimized. Hexaconazole,methyl DL-mandelate,benzoin and tebuconazole have been successfully separated on the CSP column, with column efficiency as high as 10,200 plates/m, which is comparable with some silica-based CSPs. The research has indicated that the poly(GMA-DVB) is a promising candidate for constructing CSPs for chiral separation.


Assuntos
Celulose/análogos & derivados , Microesferas , Fenilcarbamatos/química , Polímeros/química , Celulose/química , Cromatografia Líquida de Alta Pressão/métodos , Compostos de Epóxi/química , Metacrilatos/química , Porosidade , Dióxido de Silício/química , Estereoisomerismo , Triazóis/química , Compostos de Vinila/química
11.
Theranostics ; 10(21): 9808-9829, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32863961

RESUMO

Rationale: Prostate cancer has become one of the most threatening malignant tumors in men, leading to an imperative need to develop effective and safe therapies. Because of the unique metabolism of tumor cells, the tumor microenvironment (TME) exhibits distinctive properties compared with normal tissues, among which the pH difference has been utilized as an ideal antitumor strategy. Herein, we introduce a reactive oxygen species (ROS)-controlled-release nanosystem with TME-responsiveness by applying hollow mesoporous silica nanoparticles (HMSNs) as carriers loaded with calcium peroxide (CaO2) and coated with polyacrylic acid (PAA) to construct the functional material CaO2@HMSNs-PAA. The differences in pH values and exogenous ROS scavenging abilities between the tumor tissue and normal tissues and the dual pH-responsiveness from CaO2 and PAA lay a scientific foundation for the application of CaO2@HMSNs-PAA in the tumor-selective therapy for prostate cancer. Methods: The morphology and the structure of the nanosystem were characterized by the transmission electron microscope, scanning electron microscope, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, zeta potential, dynamic light scattering measurement, low-angle X-ray diffraction patterns and nitrogen adsorption/desorption isotherm. The CaO2 loading capacity and release profiles in different buffer solutions were determined by inductively coupled plasma-mass spectrometry. The in vitro intracellular uptake of CaO2@HMSNs-PAA was explored on the PC-3 prostate cancer cell line via confocal laser scanning microscopy. The CCK-8 cell proliferation assay was conducted to evaluate the cytotoxicity of CaO2@HMSNs-PAA against PC-3 cells. ROS produced by CaO2@HMSNs-PAA was observed by a fluorescence microscope. The flow cytometry was utilized to analyze the apoptosis of PC-3 cells induced by CaO2@HMSNs-PAA. The Western blot analysis was performed to detect expressions of critical mitochondria-mediated apoptosis markers in PC-3 cells after incubation with CaO2@HMSNs-PAA. The in vivo biosafety and antitumor efficacy were evaluated out on BALB/c mice and BALB/c nude mice subcutaneously transplanted with PC-3 cells, respectively. Results: Comprehensive characterizations indicated the successful synthesis of CaO2@HMSNs-PAA with significant TME-responsiveness. The experimental results demonstrated that the well-developed nanocarrier could efficiently deliver CaO2 to the tumor site and release ROS in response to the decreased pH value of TME, exerting ideal antitumor effects both in vitro and in vivo by activating the mitochondria-mediated apoptosis pathway. Simultaneously, this nanoplatform caused no detectable damage to normal tissues. Conclusions: After loading into the above nanocomposite, the free CaO2 without a significant antitumor effect can exert excellent antitumor efficacy by responsively releasing ROS under the acidic TME to induce the mitochondria-mediated apoptosis via remarkable oxidative stress and simultaneously minimize damages to normal tissues. The current study presents a new concept of "efficacy-shaping nanomedicine" for the tumor-selective treatment of prostate cancer.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Nanopartículas/química , Peróxidos/química , Neoplasias da Próstata/tratamento farmacológico , Microambiente Tumoral/efeitos dos fármacos , Resinas Acrílicas/química , Animais , Linhagem Celular , Linhagem Celular Tumoral , Portadores de Fármacos/química , Humanos , Concentração de Íons de Hidrogênio , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanomedicina/métodos , Estresse Oxidativo/efeitos dos fármacos , Células PC-3 , Porosidade , Neoplasias da Próstata/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Dióxido de Silício/química
12.
Zhongguo Gu Shang ; 33(6): 564-6, 2020 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-32573164

RESUMO

OBJECTIVE: To evaluate the effects of membrane induced by antibiotic-loaded bone cement in skin grafting for tendon exposed wound healing. METHODS: A total of 10 traumatic patients with tendon exposed wound were admitted to our department between February 2016 and December 2018, including 6 males and 4 females, with a mean age of 34.6 years old (ranged, 19 to 43 years old), and treatment duration ranged from 2 to 6 months. There were 7 cases of traffic accidents, 3 cases of mechanical belt injuries, including 8 cases of lower leg and foot wounds and 2 cases of hand back wounds. These tendons exposed wound were covered by antibiotic-loaded bone cement at the earlier stageto induce the formation of the biomembrane, and then skin grafting were performed on the induced membrane. The survival, appearance, texture, sensation of the skin grafting and healing condition of the wounds were studied. RESULTS: Among the 10 patients, skin graft survived well in 8 patients. Partial skin graft necrosis occurred in 2 patients and cured by dressing. CONCLUSION: Using antibiotic bone cement to seal the wound to form induction membrane followed by skin grafting can effectively repair the tendon exposed wound, which has the characteristics of simple operation and less trauma.


Assuntos
Cicatrização , Adulto , Antibacterianos , Cimentos Ósseos , Feminino , Humanos , Masculino , Procedimentos de Cirurgia Plástica , Transplante de Pele , Lesões dos Tecidos Moles , Tendões , Resultado do Tratamento , Adulto Jovem
13.
J Sep Sci ; 32(15-16): 2592-600, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19606442

RESUMO

A poly(N-isopropylacrylamide-co-ethylene dimethacrylate) (poly(NIPAAm-co-EDMA)) monolith was in situ prepared in the capillary and was investigated for in-tube solid-phase microextraction (SPME). NIPAAm, an acrylamide monomer with isopropyl group, was crosslinked with EDMA. PEG of 400-20,000 Da molecular weight and methanol were selected as the binary porogens. The porous structures of the resulting monoliths have been assessed by SEM, nitrogen adsorption-desorption, and pressure drop measurements. To investigate the extraction mechanism, several groups of model analytes (including neutral, acidic, and basic) were examined. The result showed that this monolithic material exhibited high extraction efficiencies for compounds under highly acidic and basic conditions, which was due to the hydrophobic interactions and excellent pH stability of the monolith. The equilibrium extraction time profiles were also monitored for model compounds to evaluate the extraction capacity of monolithic capillary. Finally, the developed monolith in-tube SPME-HPLC method was applied to the determination of three tricyclic antidepressants from urine samples.


Assuntos
Acrilamidas/química , Cromatografia Líquida de Alta Pressão/instrumentação , Reagentes de Ligações Cruzadas/química , Metacrilatos/química , Microextração em Fase Sólida/instrumentação , Antidepressivos Tricíclicos/isolamento & purificação , Antidepressivos Tricíclicos/urina , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Concentração de Íons de Hidrogênio , Peso Molecular , Polietilenoglicóis/química , Porosidade , Reprodutibilidade dos Testes , Microextração em Fase Sólida/métodos
14.
Br J Neurosurg ; 23(1): 71-5, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19234912

RESUMO

Duraplasty is critical to the maintenance of anatomical integrity and the protection of brain tissue. Allotransplantation of cadaveric dura mater was abandoned after it was found to transmit Creutzfeldt-Jakob disease (CJD). In this study, the usefulness of a xenogeneic dura mater for dural reconstruction was tested. Twelve dogs were randomly assigned to 4 groups. To simulate the condition of patients with brain surface injury, an area of approximately 2 cm x 1.5 cm of the dura mater was removed to create a defect. Xenogeneic dura mater derived from porcine pericardium was trimmed to the shape and size of the defect and sutured to the endogenous dura mater. Muscles at the apex of the skull and scalp were also sutured. Three dogs were euthanized at 3, 6, 9, and 12 months after implantation and the xenogeneic dura mater and surrounding endogenous tissue were examined macroscopically and microscopically. Three months after implantation, the graft site had begun to heal. Macroscopically, at 6, 9, and 12 months after implantation, the graft had healed completely with the surrounding tissue. No boundary between the graft and surrounding tissue was distinguishable, and the two could not be separated. The graft was smoothly epithelialized and nonadherent to the brain surface. Microscopically, the inner surface of the implant was covered with epithelial cells, and internal capillaries, subepithelial fibrous tissue deposition, and fibroblast proliferation were observed. The xenogeneic dura mater progressively degraded over time. No cysts and no neutrophilic or lymphocytic inflammatory cell response developed between the implant and the recipient brain parenchyma. The modified xenogeneic dura mater is sufficiently biocompatible to allow epithelialization of its inner surface without adherence to brain tissue. No abnormalities develop in recipients, and the xenograft is gradually biodegraded and replaced by endogenous tissue identical to the endogenous dura mater.


Assuntos
Síndrome de Creutzfeldt-Jakob/prevenção & controle , Dura-Máter/transplante , Transplante Heterólogo/métodos , Cicatrização/fisiologia , Animais , Materiais Biocompatíveis/normas , Cães , Feminino , Masculino , Modelos Animais , Distribuição Aleatória , Aderências Teciduais
15.
J Chromatogr A ; 1212(1-2): 61-7, 2008 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-18950778

RESUMO

Novel pH-responsive polymer-grafted silica was successfully synthesized through the radical "grafting from" polymerization on azo initiator-immobilized silica. The immobilization of azo initiator onto the silica surface was achieved by the reaction of surface amino groups with 4,4'-azobis(4-cyanovaleric acid chloride). The polymer-grafted silica was prepared by stirring suspension of the azo initiator-immobilized silica in anhydrous dioxane containing acrylic acid (AAc) and butyl acrylate (BA). The resulting polymer-grafted silica was demonstrated to be pH responsive to hydrophobic/hydrophilic property by reversed-phase liquid chromatography (RPLC) and hydrophilic interaction chromatography (HILIC). In RPLC mode, the retention of aromatic compounds decreased with the increase in the pH of mobile phase. However, the opposite result was obtained in HILIC mode; the retention of soybean isoflavones was stronger with the mobile phase at higher pH. Finally, the separations of sulfonamides and soybean isoflavones were carried out in RPLC mode and the separation of some nucleotides was achieved in HILIC mode.


Assuntos
Cromatografia Líquida/métodos , Nitrilas/síntese química , Ácidos Pentanoicos/síntese química , Polímeros/síntese química , Dióxido de Silício/síntese química , Acrilatos/síntese química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Isoflavonas/química , Microscopia Eletrônica de Varredura , Nucleotídeos/química , Tamanho da Partícula , Extração em Fase Sólida/métodos , Solventes/química , Sulfonamidas/química , Temperatura
16.
Talanta ; 178: 583-587, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29136866

RESUMO

The demand for fast chromatographic enantioseparation aroused the hot research in stationary phase matrix. In the present study, the flow-through silica, which is characterized by hierarchical pores of through pores in several hundred nanometer range and mesopores about 20nm, was attempted for fast enantioseparation. Thanks to the large surface area and full openness of the through pores, the flow-through silica had comparable cellulose derivative loading amount as the commercial wide-pore silica, which was impracticable for most of the core-shell particles and sub-2-µm fully porous silica. In addition, the backpressure was about two times lower in the case of the flow-through silica of the same particle size to the commercial wide-pore silica, due to the highly porous structure of the former. Another appreciated merit of the flow-through silica in small size (~2µm) was the less dependence of column efficiency on the flow rate. All of the above features rendered the flow-through silica a tremendous potential for fast enantioseparation with desired enantioselectivity, especially suitable for the polysaccharide chiral selector.


Assuntos
Celulose/análogos & derivados , Celulose/química , Cromatografia Líquida de Alta Pressão/métodos , Fenilcarbamatos/química , Dióxido de Silício/química , Porosidade , Estereoisomerismo
17.
Int J Nanomedicine ; 11: 121-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26792989

RESUMO

Tanshinones, the major lipid-soluble pharmacological constituents of the Chinese medicinal herb Tanshen (Salvia miltiorrhiza), have attracted growing scientific attention because of the prospective biomedical applications of these compounds. Numerous pharmacological activities, including anti-inflammatory, anticancer, and cardio-cerebrovascular protection activities, are exhibited by the three primary bioactive constituents among the tanshinones, ie, tanshinone I (TNI), tanshinone IIA (TNIIA), and cryptotanshinone (CPT). However, due to their poor solubility and low dissolution rate, the clinical applications of TNI, TNIIA, and CPT are limited. To solve these problems, many studies have focused on loading tanshinones into liposomes, nanoparticles, microemulsions, cyclodextrin inclusions, solid dispersions, and so on. In this review, we aim to offer an updated summary of the biological activities and drug delivery systems of tanshinones to provide a reference for these constituents in clinical applications.


Assuntos
Abietanos/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Fenantrenos/farmacologia , Abietanos/administração & dosagem , Ciclodextrinas/administração & dosagem , Ciclodextrinas/química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Emulsões/química , Emulsões/farmacologia , Humanos , Lipossomos/administração & dosagem , Lipossomos/química , Lipossomos/farmacologia , Nanopartículas/administração & dosagem , Nanopartículas/química , Fenantrenos/administração & dosagem , Salvia miltiorrhiza/química , Solubilidade
18.
Am J Transl Res ; 8(2): 670-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27158359

RESUMO

Odontogenic ameloblast associated protein (ODAM) is a protein contributed to cell adhesion and has been shown to express in normal prostate tissue, but the expression and significance of ODAM in prostate cancer remain unknown. In this study, we detected the protein expressions of ODAM in 88 prostate cancer tissues with immunohistochemical staining, and found that 53 cases (60.2%) was high expression of ODAM, which was shown in the cytoplasm and paranuclear regions. Furthermore, low expression of ODAM was significantly correlated with lymph node metastasis, preoperative PSA and Gleason score, but not with mean age, follow-up duration, PSM rate and distribution of pathological T stage. Additionally, our results of multivariate analysis showed that low ODAM expression was an independent predictor of biomedical recurrence, while the positive lymph node metastasis, Gleason score, and preoperative PSA were not the independent risks for biomedical recurrence. Overexpression of ODAM did not inhibit the growth of prostate cancer cells PC3, but significant suppressed their invasion and migration with decrease of the protein levels of MMP-2. These results suggest that ODAM is a predictor for biomedical recurrence and inhibits the migration and invasion of prostate cancer.

19.
Macromol Biosci ; 5(10): 974-82, 2005 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-16208631

RESUMO

Surface-active microporous membranes were prepared from the poly(vinylidene fluoride)-graft-poly(2-(2-bromoisobutyryloxy)ethyl acrylate) copolymer (PVDF-g-PBIEA copolymer) by phase inversion in water. The PBIEA side chains could function as initiators for the atom transfer radical polymerization (ATRP) of 2-(N,N-dimethylamino)ethyl methacrylate on the membrane surfaces to give rise to the PVDF-g-PBIEA-ar-PDMAEMA membranes. N-alkylation with hexyl bromide and nitromethane gave rise to the quanternized PVDF-g-PBIEA-ar-QPDMAEMA membranes with polycation chains chemically tethered on the membrane surface, including the pore surfaces. The changes in the surface morphology and the surface chemical composition were confirmed by scanning electron microscopy and X-ray photoelectron spectroscopy. The scanning electron microscopy revealed that, in comparison to the pristine PVDF-g-PBIEA membranes, not only could the PVDF-g-PBIEA-ar-QPDMAEMA membranes remove the Gram-negative bacterium Escherichia coli but also inhibited the bacterial reproduction on the membranes to a significant extent.


Assuntos
Antibacterianos/química , Membranas Artificiais , Polivinil/química , Acrilatos/química , Escherichia coli/química , Microscopia Eletrônica de Varredura , Polímeros/química , Espectrometria por Raios X , Propriedades de Superfície
20.
Di Yi Jun Yi Da Xue Xue Bao ; 25(5): 488-92, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15897116

RESUMO

OBJECTIVE: To investigate the impact of one versus two distal locking bolts on the mechanical properties of tibial interlocking intramedullary nails. METHODS: Twenty 9-mm titanium alloy locking nails were divided into two equal groups in which the nails were fixed with only one and two distal locking bolts, respectively. Each group was further divided into two sub-groups for compression and torsion tests separately using a universal material-testing machine. RESULTS: In the compression tests, the average maximum strength of double bolts was greater than that of the single bolt (P<0.05), but the number of the bolts did not significantly affect the results of the torsion tests in terms of the either the maximum torsion moment or angle (P>0.05). CONCLUSION: One distal bolt is sufficient for fixing stable fractures and double bolts are recommended for management of serious fractures. The model we used is convenient and economic for examining the biomechanics of the tibial nails, especially for comparative purposes.


Assuntos
Pinos Ortopédicos , Fixação Intramedular de Fraturas/instrumentação , Teste de Materiais , Tíbia/cirurgia , Ligas , Fenômenos Biomecânicos , Fraturas da Tíbia/cirurgia , Titânio
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