Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Biomacromolecules ; 14(7): 2305-16, 2013 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-23701412

RESUMO

We show for the first time the possibility of using networks of amyloid fibrils, adsorbed to solid supports and with plasma polymer coatings, for the fabrication of chemically homogeneous surfaces with well-defined nanoscale surface features reminiscent of the topography of the extracellular matrix. The robust nature of the fibrils allows them to withstand the plasma polymer deposition conditions used with no obvious deleterious effect, thus enabling the underlying fibril topography to be replicated at the polymer surface. This effect was seen despite the polymer coating thickness being an order of magnitude greater than the fibril network. The in vitro culture of fibroblast cells on these surfaces resulted in increased attachment and spreading compared to flat plasma polymer films with the same chemical composition. The demonstrated technique allows for the rapid and reproducible fabrication of substrates with nanoscale fibrous topography that we believe will have applications in the development of new biomaterials allowing, for example, the investigation of the effect of extracellular matrix mimicking nanoscale morphology on cellular phenotype.


Assuntos
Amiloide/química , Materiais Biocompatíveis/química , Nanoestruturas , Animais , Adesão Celular/fisiologia , Linhagem Celular , Matriz Extracelular/química , Camundongos , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Polímeros/química , Propriedades de Superfície
2.
Front Bioeng Biotechnol ; 11: 1273318, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026888

RESUMO

Oromandibular tumors or osteoradionecrosis often lead to extensive composite defects encompassing intraoral, bone and extraoral tissues. A single flap cannot simultaneously offer sufficient bone and soft tissue. The combination of free flaps could be a prospective approach to overcome the challenge. The study aims to assess the efficacy of virtual surgical planning (VSP) and 3D printing assisted fibula osteoseptocutaneous flap (FOSCF) combined with anterolateral thigh flaps (ALT) in reconstructing extensive composite defects in the oromandibular region. A retrospective analysis was conducted on 8 patients who underwent reconstruction using FOSCFs combined with ALTs. Post-surgical excision of the lesions, we obtained mean values for the defects of intraoral soft tissue, bone, extraoral soft tissue, namely, being 42.7 cm2, 96 mm, and 68.9 cm2. The mean surgical procedures took 712.5 min. A total of 16 flaps were harvested and transplanted for the 8 patients, with all successfully surviving. Postoperatively, complications manifested as localized intraoral infections in 2 cases, intermuscular vein thrombosis in another 2 cases, and pulmonary infections in 2 patients. Two patients unfortunately experienced tumor recurrence, at 12 and 3 months post-operation respectively. For the surviving 6 patients, the average follow-up period was 12.2 months. Regarding patient satisfaction, one expressed dissatisfaction with the contour of the mandible, and two exhibited moderate trismus. Objective assessments identified 1 case of oral incontinence and 2 cases where external flap contractures were observed. All 8 patients experienced restoration of masticatory function and were able to consume a soft diet within a month post-surgery. VSP/3D printing assisted FOSCFs combined with ALTs can be performed safely to reconstruct the extensive composite tissue defects in our study, with desirable esthetic and functional results, and it is a reliable option in selecting patients with defects involving multiple tissue types. However, the benefits of this method needed more cases to validate.

3.
J Am Chem Soc ; 134(2): 1235-42, 2012 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-22257265

RESUMO

Comparative studies of bulk samples of hydrolytically degradable poly(lactic acid) (PLA) vs core-shell block copolymer micelles having PLA cores revealed remarkable acceleration in the proteinase K enzymatic hydrolysis of the nanoparticulate forms and demonstrated that even with amidation-based shell cross-linking the core domain remained accessible. Kinetic analyses by (1)H NMR spectroscopy showed less than 20% lactic acid released from enzymatically catalyzed hydrolysis of poly(l-lactic acid) in bulk, whereas ca. 70% of the core degraded within 48 h for block copolymer micelles of poly(N-(acryloyloxy)succinimide-copolymer-N-acryloylmorpholine)-block-poly(L-lactic acid) (P(NAS-co-NAM)-b-PLLA), with only a slight reduction to ca. 50% for the shell cross-linked derivatives. Rigorous characterization measurements by NMR spectroscopy, fluorescence spectroscopy, dynamic light scattering, atomic force microscopy, and transmission electron microscopy were employed to confirm core excavation. These studies provide important fundamental understanding of the effects of nanoscopic dimensions on protein-polymer interactions and polymer degradability, which will guide the development of these degradable nanoconstructs to reach their potential for controlled release of therapeutics and biological clearance.


Assuntos
Endopeptidase K/metabolismo , Ácido Láctico/química , Nanopartículas/química , Polímeros/química , Cinetina , Espectroscopia de Ressonância Magnética , Micelas , Modelos Moleculares , Estrutura Molecular , Poliésteres
4.
J Am Chem Soc ; 134(9): 3938-41, 2012 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-22360307

RESUMO

Amphiphilic block copolymer nanoparticles are conjugated with uropathogenic Escherichia coli type 1 pilus adhesin FimH(A) through amidation chemistry to enable bladder epithelial cell binding and internalization of the nanoparticles in vitro.


Assuntos
Adesinas de Escherichia coli/química , Células Epiteliais/citologia , Escherichia coli/química , Escherichia coli/citologia , Proteínas de Fímbrias/química , Nanopartículas/química , Polímeros/síntese química , Modelos Moleculares , Tamanho da Partícula , Polímeros/química , Propriedades de Superfície
5.
Open Med (Wars) ; 17(1): 768-780, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35529473

RESUMO

This study examined the potential mechanism of zoledronate on interleukin (IL)-1ß-induced temporomandibular joint osteoarthritis (TMJOA) chondrocytes, using IL-1ß-induced rabbit immortalized mandibular condylar chondrocytes cultured with zoledronate. Cell viability, apoptosis, mRNA, and protein expression of relevant genes involved in extracellular matrix (ECM) degradation, apoptosis, and Wnt/ß-catenin signaling were examined. The involvement of the Wnt/ß-catenin signaling was examined using Wnt/ß-catenin inhibitor (2-(4-(trifluoromethyl)phenyl)-7,8-dihydro-5H-thiopyrano[4,3-d]pyrimidin-4-ol (XAV-939)) and activator lithium chloride (LiCl). Aggrecan and type II collagen were downregulated by zoledronate, especially with 100 nM for 48 h (p < 0.01), consistently with the upregulation of A disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4) (p < 0.001), matrix metalloprotease-9 (MMP-9) (p < 0.01), caspase-3 (p < 0.001) and downregulation of proliferating cell nuclear antigen (PCNA) (p < 0.01). The apoptotic rate increased from 34.1% to 45.7% with 100 nM zoledronate for 48 h (p < 0.01). The effects of zoledronate on ADAMTs4 (p < 0.001), MMP-9 (p < 0.001), caspase-3 (p < 0.001), and PCNA (p < 0.01) were reversed by XAV-939, while LiCl increased caspase-3 expression (p < 0.01). In conclusion, zoledronate enhances IL-1ß-induced ECM degradation and cell apoptosis in TMJOA chondrocytes. Wnt/ß-catenin signaling might be involved in this process, but additional studies are necessary to determine the exact involvement of Wnt/ß-catenin signaling in chondrocytes after zoledronate treatment.

6.
J Org Chem ; 76(10): 3654-63, 2011 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-21462999

RESUMO

Clemoarmanoside A and Clemahexapetoside A, two novel cyclic dimers of 4-(glycosyloxy)benzoates containing the unusual d-allopyranose as one of the sugar units, were synthesized for the first time. The convenient synthetic approach was adapted to the assembly of the symmetrical trimeric, tetrameric, and pentameric congeners. The synthesis clarified the discrepancy in the NMR data reported for the natural products. X-ray diffraction analysis of Clemahexapetoside A revealed that it adopted an armchair conformation with two carbohydrate rings as the arms and two aromatic rings as the back and seat, respectively.


Assuntos
Benzoatos/química , Glicosídeos/química , Glicosídeos/síntese química , Compostos Macrocíclicos/química , Compostos Macrocíclicos/síntese química , Polímeros/química , Polímeros/síntese química , Glicosilação
7.
Shanghai Kou Qiang Yi Xue ; 30(2): 219-224, 2021 Apr.
Artigo em Zh | MEDLINE | ID: mdl-34109367

RESUMO

PURPOSE: To use three-dimensional reconstruction measurement, preoperative diagnosis, surgical design, surgical simulation, guide plate production, navigation verification and effect evaluation of orthognathic surgery assisted by digital technology, in order to explore more scientific and reasonable programs and procedures of orthognathic surgery. METHODS: Twenty-five patients with congenital dental and maxillofacial deformity were selected as the experimental subjects, craniofacial spiral CT was conducted before surgery and CT data were imported into Mimics 20.0 software to establish a 3D head digital model. The bone landmarks in three-dimensional reconstruction digital model were selected, measured, analyzed and diagnosed, and the design of the surgical plan and the production of the guide plates were performed. Surgical navigation system was used to confirm the maxillary position, verify the bone retention and guide precise bone grinding during operation. Craniofacial spiral CT was conducted 1 week after surgery for postoperative validation of the surgical design protocol. Statistical analysis was performed using SPSS 24.0 software package. RESULTS: All 25 patients were operated according to the digital orthognathic surgery design and procedure.There were no significant differences in X, Y and Z three-dimensional directions in 10 actual landmarks between the postoperative actual head model and the preoperative predictive head model(P>0.05). CONCLUSIONS: Orthognathic surgery assisted by digital technology has the advantages of precision and minimal invasiveness.


Assuntos
Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Cirurgia Assistida por Computador , Tecnologia Digital , Humanos , Imageamento Tridimensional , Maxila/diagnóstico por imagem , Maxila/cirurgia , Tomografia Computadorizada Espiral
8.
Shanghai Kou Qiang Yi Xue ; 30(4): 394-401, 2021 Aug.
Artigo em Zh | MEDLINE | ID: mdl-34693433

RESUMO

PURPOSE: To investigate the influence of the position of the upper and lower jaws on the anatomical structure of pharynx before and after orthognathic surgery in patients with skeletal Class Ⅲ malocclusion. METHODS: Craniofacial CT scan and speech data were collected from 31 patients with skeletal Class Ⅲ malocclusion before and 3 months after surgery. The collected CT data was imported into Dolphin imaging 11.95 software to establish a digital original model, and the anatomical structure of the pharynx was measured and analyzed. Speech data were analyzed objectively and subjectively by Computerized Speech Lab 4500b and professional speech specialists. Statistical analysis was performed using SPSS 24.0 software package. RESULTS: The distance from the lower edge of the soft palate to the posterior pharyngeal wall, the shortest distance from the posterior margin of the tongue to the posterior pharyngeal wall and its corresponding cross-sectional area were significantly different from those before surgery (P<0.05). The changes of SNA, SNB, ANB, OJ, and OBJ before and after surgery were significant in this series. Importantly, the speech intelligibility of orthognathic patients before and after surgery changed significantly subjectively (P<0.05). Objectively, the postoperative vowels /a/B2, B3, B4, /i/B1,B2, /u/B1,B2 and B4 of the patients were significantly different from those before surgery. There was no significant difference in the lower limit frequency of the consonants /x/, /zh/, /s/, the energy value of /zh/ and the grammatical form of /z/ before and after surgery. The maxillary advancement distance was highly correlated or significantly correlated with △S1, △VOP, and voice changes. CONCLUSIONS: Orthognathic surgery moves the upper and lower jaws to cause changes in the anatomy of the pharyngeal cavity, leading to changes of postoperative speech.


Assuntos
Má Oclusão Classe III de Angle , Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Cefalometria , Humanos , Má Oclusão Classe III de Angle/diagnóstico por imagem , Má Oclusão Classe III de Angle/cirurgia , Mandíbula , Maxila , Faringe/diagnóstico por imagem , Faringe/cirurgia , Fala
9.
Shanghai Kou Qiang Yi Xue ; 28(2): 158-164, 2019.
Artigo em Zh | MEDLINE | ID: mdl-31384901

RESUMO

PURPOSE: To investigate the change ratios of soft and hard tissue after orthognathic surgery three-dimensionally in osseous Class Ⅲ patients, in order to predict postoperative soft tissue three-dimensionally. METHODS: Twenty adult patients were selected as the experimental group, craniofacial spiral CT and three-dimensional (3D) stereophotogrammetry were conducted 2 weeks before surgery and 3 months after surgery. Dolphin imaging software was used to establish 3D image digitizing model and 3D measurement coordinate system. Nineteen soft and hard tissue land marks were selected and matched into 12 pairs. 3D coordinate value of these landmarks were read both before and after surgery and were used for statistical analysis with SPSS 22.0 software package. RESULTS: There was a linear relationship only in Pn/A, Gn'/Gn and Me'/Me in X axis, in Gn'/Gn in Y axis and all pairs of landmarks had a close correlation except UL'/UI and UL/SPr in Z axis. Additionally, the change ratio between soft and hard tissue landmarks of mandible was greater than maxilla. CONCLUSIONS: The changes of soft and hard tissue after orthognathic surgery only lie in Z axis(forward and backward), each pair of matched landmarks exhibits a linear relationship, and the change ratio of mandible is greater than the maxilla.


Assuntos
Imageamento Tridimensional , Má Oclusão Classe III de Angle , Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Adulto , Cefalometria , Humanos , Má Oclusão Classe III de Angle/diagnóstico por imagem , Mandíbula , Maxila
10.
Environ Pollut ; 245: 965-974, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30682753

RESUMO

At present, the study of microplastic sources is in a relatively preliminary stage due to the complexity of microplastic features in the environment. Based on a literature review, we developed a source-specific classification system for the quantitative analysis of microplastic sources. The classification system includes ten types of microplastics based on morphology and composition and can identify their main sources and the associated probabilities. To reflect the complexity of types and sources in the regional combination of microplastics, we first propose a microplastic diversity index (D1-D'(MP)). We use the South China Sea as an example to carry out quantitative source analysis and calculate the diversity index. Eight types of microplastics were found, mainly consisting of maritime coatings (type "Gran_coat") (33.0%) and synthetic fibers (type "Fib_thin") (29.6%). We also found that the diversity increased with offshore distance. In addition, we partitioned surface microplastics globally according to a two-dimensional microplastic abundance-diversity index. We believe that these indicators can effectively reflect pollution status and ultimately lead to different types of control measures. In the future, additional indicators for the characterization of microplastics must be included in the classification system to establish a one-to-one source analysis system for microplastic characteristics and source apportionment. In general, our study may provide new insights into the establishment of more accurate and quantitative source apportionment techniques and effective pollution control.


Assuntos
Monitoramento Ambiental/métodos , Poluição Difusa/análise , Plásticos/análise , Água do Mar/química , Poluentes Químicos da Água/análise , China , Oceanos e Mares , Plásticos/classificação , Poluentes Químicos da Água/classificação
11.
Arch Oral Biol ; 102: 16-25, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30954805

RESUMO

OBJECTIVES: To develop PLGA/nHA scaffold containing BMP-2 cell growth factor chitosan sustained release system as tissue engineered bone for repairing large jaw defects, test its sustained release rhBMP-2 efficiency in vitro, and evaluate its Osteogenesis in rabbit mandibular defects. METHODS: Tissue engineered bone scaffold complexes were prepared by complexing rhBMP-2 loaded chitosan (CS / rhBMP-2) nano sustained release carrier with PLGA / nHA scaffold carrier by 3D printing. In vitro, the porosity, pore size and degradation rate and the dose-time effect relationship of cytokine release were examined. Micro-CT, hematoxylin/eosin staining, Masson staining and immunohistochemistry were determined at week 4, week 8 and week 12 in 18 rabbits. RESULTS: In vitro, the porosity was (73.64 ± 1.82)%, and the average pore diameter was (431.31 ± 18.40) µm. The cumulative release was only 9.54 ± 0.86% within 48 h and 61.38 ± 2.39% on the 30th day. In vivo, Micro-CT examination showed that the BMD and the bone volume fraction at 4, 8, and 12 weeks were higher in the implantation group than in the control group. In the 12th week, Masson staining showed that new bone occupied 19.2% of the defect area in the control group, whereas the proportion of new bone reached 45.5% in the experimental group. CONCLUSIONS: PLGA/nHA/CS/rhBMP-2 scaffold complex effectively controlled the early burst effect of rhBMP-2. The bone tissue engineering scaffold complex had good biocompatibility and induced osteogenic effects. It successfully repaired the experimental bone defect area of the rabbit mandible.


Assuntos
Mandíbula , Animais , Proteína Morfogenética Óssea 2 , Regeneração Óssea , Quitosana , Preparações de Ação Retardada , Osteogênese , Coelhos , Proteínas Recombinantes , Engenharia Tecidual , Alicerces Teciduais , Fator de Crescimento Transformador beta
12.
Water Res ; 162: 214-224, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31276985

RESUMO

Primary microplastics are mostly produced as part of the daily plastic product use. The emission process is often invisible but poses potential ecological hazards. Thus, primary microplastics deserve public attention. Due to China's huge population base and its rapid economic development, primary microplastics emissions are of both regional and global significance. This study is the first to establish the emission inventory of primary microplastics in mainland China. It was estimated that the primary microplastic waste from mainland China amounts to 737.29 Gg, and one-sixth of this amount entered the aquatic environment in 2015. The highest proportion of this waste was attributable to tire dust and synthetic fiber, accounting for 53.91% and 28.77% of the total respectively, in mainland China. The primary microplastics emissions mainly depend on the population, followed by the level of economic development. It was roughly estimated that 538 g of microplastics is produced by each person in China. At the grid scale, the spatial difference in the total primary microplastics emissions in mainland China primarily depends on the population density distribution and transportation network. We studied the entire life cycle of several sources of microplastics, from production to discharge into the aquatic environment. We suggested different control measures under different nodes. Increasing microplastics treatment in sewage treatment plants should be a short-term viable way to achieve some measure of reduction in their entry to the environment in mainland China. Our research can not only raise public awareness about primary microplastics, but can also guide the development of environmental policies to reduce plastic pollution.


Assuntos
Plásticos , Poluentes Químicos da Água , China , Monitoramento Ambiental , Poluição Ambiental
13.
Biomacromolecules ; 9(10): 2826-33, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18795785

RESUMO

Three hyperbranched fluoropolymers were synthesized and their micelles were constructed as potential (19)F MRI agents. A hyperbranched star-like core was first synthesized via atom transfer radical self-condensing vinyl (co)polymerization (ATR-SCVCP) of 4-chloromethyl styrene (CMS), lauryl acrylate (LA), and 1,1,1-tris(4'-(2''-bromoisobutyryloxy)phenyl)ethane (TBBPE). The polymerization gave a small core with M n of 5.5 kDa with PDI of 1.6, which served as a macroinitiator. Trifluoroethyl methacrylate (TFEMA) and tert-butyl acrylate (tBA) in different ratios were then "grafted" from the core to give three polymers with M(n) of about 120 kDa and PDI values of about 1.6-1.8. After acidolysis of the tert-butyl ester groups, amphiphilic, hyperbranched star-like polymers with M(n) of about 100 kDa were obtained. These structures were subjected to micelle formation in aqueous solution to give micelles having TEM-measured diameters ranging from 3-8 nm and DLS-measured hydrodynamic diameters from 20-30 nm. These micelles gave a narrow, single resonance by (19)F NMR spectroscopy, with a half-width of approximately 130 Hz. The T1/T2 parameters were about 500 and 50 ms, respectively, and were not significantly affected by the composition and sizes of the micelles. (19)F MRI phantom images of these fluorinated micelles were acquired, which demonstrated that these fluorinated micelles maybe useful as novel (19)F MRI agents for a variety of biomedical studies.


Assuntos
Radioisótopos de Flúor/química , Imageamento por Ressonância Magnética/métodos , Polímeros/química , Acetatos/química , Varredura Diferencial de Calorimetria/métodos , Meios de Contraste/farmacologia , Ácidos Láuricos/química , Espectroscopia de Ressonância Magnética , Metacrilatos/química , Micelas , Microscopia de Força Atômica/métodos , Microscopia Eletrônica de Transmissão , Peso Molecular , Poli-Hidroxialcanoatos/química , Poliestirenos/química , Propriedades de Superfície
14.
Chem Asian J ; 11(2): 207-10, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26548455

RESUMO

Metal-organic framework (MOF) UiO-66 thin films are solvothermally grown on conducting substrates. The as-synthesized MOF thin films are subsequently dried by a supercritical process or treated with polydimethylsiloxane (PDMS). The obtained UiO-66 thin films show excellent molecular sieving capability as confirmed by the electrochemical studies for redox-active species with different sizes.


Assuntos
Ácidos Carboxílicos/química , Zircônio/química , Técnicas Eletroquímicas , Membranas Artificiais , Microscopia Eletrônica de Varredura , Estrutura Molecular , Oxirredução , Porosidade , Propriedades de Superfície , Termodinâmica
15.
Arch Oral Biol ; 68: 105-15, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27127843

RESUMO

OBJECTIVE: Temporomandibular joint osteoarthritis (TMJOA) is a complex disease with strong genetic and epigenetic components in its pathogenesis. The aim of this study was to evaluate DNA methylation in mandibular head cartilage in different phases of experimentally-induced TMJOA in rats. DESIGN: DNA methylation was evaluated using microarrays in the mandibular head cartilage of early, intermediate and late stage experimentally-induced TMJOA, and of the normal age-matched control groups. Genes with differentially methylated CpG sites were analyzed to reveal the over-represented gene ontologies and pathways at different stages, and were compared with published expression profiles to assess their overlappings. The DNA methylation patterns of the target genes were validated by methylated DNA immunoprecipitation qPCR in additional independent cartilage samples and mRNA levels were analyzed by real-time PCR. RESULTS: We observed 9489 differentially methylated regions between the TMJOA and controls. A total of 440 consistently altered genes were revealed in all three stages; most (80%) were hypomethylated and many were associated with cell cycle regulation. We also detected different DNA methylation changes in early and late stage TMJOA (Rearly=0.68, Rlate=0.47), while the differences between age-matched healthy cartilage were subtle. Strong inverse changes between methylation status and mRNA levels were confirmed in Adamts5, Chad, Cldn11 and Tnf. CONCLUSIONS: Our data reveals dynamic DNA methylation patterns during the progression of TMJOA, with a different host of genes and pathways. The changes of cartilage DNA methylation patterns might contribute to understand the etiologic mechanisms of TMJOA epigenetically.


Assuntos
Metilação de DNA , Osteoartrite/genética , Transtornos da Articulação Temporomandibular/genética , Articulação Temporomandibular/fisiopatologia , Proteína ADAMTS5 , Animais , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Ciclo Celular/genética , Claudinas , Impressões Digitais de DNA , Modelos Animais de Doenças , Progressão da Doença , Masculino , Mandíbula/patologia , Redes e Vias Metabólicas , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Osteoartrite/metabolismo , Osteoartrite/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Articulação Temporomandibular/metabolismo , Articulação Temporomandibular/patologia , Transtornos da Articulação Temporomandibular/metabolismo , Transtornos da Articulação Temporomandibular/patologia
16.
Clin Lung Cancer ; 17(2): 119-27, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26781346

RESUMO

BACKGROUND: Mecapegfilgrastim (code name HHPG-19K) is a biosimilar to pegylated recombinant human granulocyte-colony stimulating factor (PEG-rhG-CSF). The efficacy and safety of mecapegfilgrastim, using a regimen of once-per-cycle injection of 100-µg/kg or a fixed 6-mg dose, were evaluated for the prophylactic therapy for neutropenia in patients with advanced non-small-cell lung cancer (NSCLC) who were treated with myelosuppressive chemotherapy. MATERIALS AND METHODS: Patients were randomized (1:1:1) blindly to 3 treatment arms to receive a single injection of mecapegfilgrastim 100 µg/kg, a 6-mg fixed dose of mecapegfilgrastim, or saline (control) in cycle 1. In cycles 2 to 4 following unblinding at the end of cycle 1, patients in the control arm received daily injections of short-acting rhG-CSF at a dose of 5 µg/kg, whereas patients in the 2 mecapegfilgrastim arms continued the same treatment as in cycle 1. All patients received 4 chemotherapy cycles of docetaxel combined with cisplatin or carboplatin every 21 days. The primary endpoint was the incidence of grade ≥ 3 neutropenia in cycle 1. RESULTS: A single dose of 100 µg/kg or a fixed 6-mg dose of mecapegfilgrastim per cycle effectively reduced chemotherapy-induced neutropenia and was comparable to daily rhG-CSF with regard to all efficacy endpoints, including incidence of grade ≥ 3 neutropenia, incidence of febrile neutropenia, duration of grade ≥ 3 neutropenia, and time to neutrophil recovery. No difference in efficacy parameters was observed between the 2-dose regimens of mecapegfilgrastim across all cycles. Mecapegfilgrastim was well-tolerated and was as safe as daily rhG-CSF. CONCLUSION: Once-per-cycle injection of mecapegfilgrastim is as effective and safe as daily rhG-CSF for prophylaxis of chemotherapy-induced neutropenia in patients with NSCLC. Mecapegfilgrastim (fixed 6-mg dose) is recommended in clinical practice for its convenient dose management.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Medicamentos Biossimilares/administração & dosagem , Carcinoma de Células Pequenas/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Neutropenia/prevenção & controle , Neutrófilos/efeitos dos fármacos , Polietilenoglicóis/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Pequenas/complicações , Carcinoma de Células Pequenas/patologia , China , Protocolos Clínicos , Feminino , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mielopoese/efeitos dos fármacos , Estadiamento de Neoplasias , Neutropenia/etiologia , Neutrófilos/fisiologia , Proteínas Recombinantes/administração & dosagem , Resultado do Tratamento
17.
J Biomed Mater Res A ; 73(2): 171-81, 2005 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15759258

RESUMO

A surface modification technique was developed for the covalent immobilization of poly(vinyl alcohol) (PVA)-heparin hydrogel onto electrically conductive polypyrrole (PPY) film with the objective of achieving controlled release of heparin. First, aldehyde groups were introduced onto PPY film through poly(ethylene glycol) monomethacrylate graft copolymerization and subsequent oxidation in acetic anhydride and dimethyl sulfoxide mixture. Then, the prepared PVA-heparin hydrogel was cast onto the PPY film and covalently immobilized to the film through the reaction between the aldehyde groups on the PPY film and the hydroxyl groups of PVA. X-ray photoelectron spectroscopy was used to characterize the surface-modified film after each stage. The strong attachment of the PVA-heparin layer on the PPY film was confirmed by peel test and scanning electron microscopy. The release behavior of heparin from the substrate with and without electrical stimulation was studied and the experimental results showed that the heparin release rate from the prepared substrate using an electric current of 3.5 mA is twofold higher than that without current.


Assuntos
Materiais Biocompatíveis , Heparina/metabolismo , Polímeros , Álcool de Polivinil , Pirróis , Preparações de Ação Retardada , Estimulação Elétrica , Fatores de Tempo
18.
Shanghai Kou Qiang Yi Xue ; 24(1): 107-10, 2015 Feb.
Artigo em Zh | MEDLINE | ID: mdl-25858380

RESUMO

PURPOSE: To assess the change of patients' psychological status before and after orthognathic surgery. METHODS: The psychological status in 36 patients were assessed before and after orthognathic surgery using the SCL-90 questionnaire. The patients were allowed to evaluate the changes of mastication, facial aesthetics, pronunciation and function of temporomandibular joint subjectively through the questionnaire. The data were analyzed using SPSS13.0 software package. RESULTS: Six factors including obsessive-compulsive symptoms, interpersonal sensitivity, depression, anxiety, phobic anxiety and psychoticism were significantly higher than norm preoperatively. No obvious abnormalities were found 2 years after operation. The self-evaluated quotas by patients after operation were significantly improved compared with those preoperatively. CONCLUSIONS: The patients' psychosomatic symptoms are significantly improved after operation. No significant difference is found compared with ordinary people concerning psychological health.


Assuntos
Cirurgia Ortognática , Transtornos Psicofisiológicos , Humanos , Mastigação , Inquéritos e Questionários
19.
ACS Nano ; 7(6): 4977-87, 2013 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-23718195

RESUMO

The use of nebulizable, nanoparticle-based antimicrobial delivery systems can improve efficacy and reduce toxicity for treatment of multi-drug-resistant bacteria in the chronically infected lungs of cystic fibrosis patients. Nanoparticle vehicles are particularly useful for applying broad-spectrum silver-based antimicrobials, for instance, to improve the residence time of small-molecule silver carbene complexes (SCCs) within the lung. Therefore, we have synthesized multifunctional, shell cross-linked knedel-like polymeric nanoparticles (SCK NPs) and capitalized on the ability to independently load the shell and core with silver-based antimicrobial agents. We formulated three silver-loaded variants of SCK NPs: shell-loaded with silver cations, core-loaded with SCC10, and combined loading of shell silver cations and core SCC10. All three formulations provided a sustained delivery of silver over the course of at least 2-4 days. The two SCK NP formulations with SCC10 loaded in the core each exhibited excellent antimicrobial activity and efficacy in vivo in a mouse model of Pseudomonas aeruginosa pneumonia. SCK NPs with shell silver cation-load only, while efficacious in vitro, failed to demonstrate efficacy in vivo. However, a single dose of core SCC10-loaded SCK NPs (0.74 ± 0.16 mg Ag) provided a 28% survival advantage over sham treatment, and administration of two doses (0.88 mg Ag) improved survival to 60%. In contrast, a total of 14.5 mg of Ag(+) delivered over 5 doses at 12 h intervals was necessary to achieve a 60% survival advantage with a free-drug (SCC1) formulation. Thus, SCK NPs show promise for clinical impact by greatly reducing antimicrobial dosage and dosing frequency, which could minimize toxicity and improve patient adherence.


Assuntos
Anti-Infecciosos/farmacologia , Nanopartículas/química , Prata/química , Aerossóis , Animais , Anti-Infecciosos/efeitos adversos , Anti-Infecciosos/química , Técnicas de Química Sintética , Inflamação/induzido quimicamente , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Modelos Moleculares , Conformação Molecular , Polímeros/química , Pseudomonas aeruginosa/efeitos dos fármacos
20.
Bioresour Technol ; 104: 473-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22113070

RESUMO

The influence of introduction of cyanuric chloride on glucose's yield (Y) in acid-catalyzed hydrolysis of microcrystalline cellulose (MCC) has been studied. The content of cyanuric chloride (C) in modified MCCs was determined by X-ray photoelectric spectroscopy. The chemical structures of modified MCCs were analyzed by Fourier transformation-infrared spectroscopy and cross polarization/magic angle spinning (13)C nuclear magnetic resonance. Crystal index (CI) and the ratio (R) representing the sum of content of (1 ̅10) and (110) to that of (200) were calculated based on diffraction intensity in wide angle X-ray diffraction (WAXD). Hydrolysis experiment and WAXD show that Y, CI and R vary with C. The modified MCC containing 3.9 mol% of cyanuric chloride has the highest Y, the highest R and the lowest CI. Variations of CI and R show that the chemical modification changed the proportion of crystal/amorphous and crystal planes, both of which influence glucose's generation in hydrolysis of cellulose.


Assuntos
Celulose/química , Cristalização/métodos , Glucose/síntese química , Triazinas/química , Hidrólise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA