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1.
Plant J ; 119(2): 1014-1029, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38805573

RESUMO

Cassava, a pivotal tropical crop, exhibits rapid growth and possesses a substantial biomass. Its stem is rich in cellulose and serves as a crucial carbohydrate storage organ. The height and strength of stems restrict the mechanised operation and propagation of cassava. In this study, the triple helix transcription factor MeGT2.6 was identified through yeast one-hybrid assay using MeCesA1pro as bait, which is critical for cellulose synthesis. Over-expression and loss-of-function lines were generated, and results revealed that MeGT2.6 could promote a significant increase in the plant height, stem diameter, cell size and thickness of SCW of cassava plant. Specifically, MeGT2.6 upregulated the transcription activity of MeGA20ox1 and downregulated the expression level of MeGA2ox1, thereby enhancing the content of active GA3, resulting in a large cell size, high plant height and long stem diameter in cassava. Moreover, MeGT2.6 upregulated the transcription activity of MeCesA1, which promoted the synthesis of cellulose and hemicellulose and produced a thick secondary cell wall. Finally, MeGT2.6 could help supply additional substrates for the synthesis of cellulose and hemicellulose by upregulating the invertase genes (MeNINV1/6). Thus, MeGT2.6 was found to be a multiple regulator; it was involved in GA metabolism and sucrose decomposition and the synthesis of cellulose and hemicellulose.


Assuntos
Celulose , Regulação da Expressão Gênica de Plantas , Giberelinas , Manihot , Proteínas de Plantas , Manihot/genética , Manihot/metabolismo , Celulose/metabolismo , Celulose/biossíntese , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Giberelinas/metabolismo , Parede Celular/metabolismo , Crescimento Celular , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Caules de Planta/genética , Caules de Planta/metabolismo , Caules de Planta/crescimento & desenvolvimento , Polissacarídeos/metabolismo
2.
Ann Plast Surg ; 92(6): 647-652, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38717142

RESUMO

BACKGROUND: The repair of facial skin and soft tissue defects remains a clinical challenge. The author introduced a novel "table tennis racquet" random skin flap for wound repair after facial skin cancer excision and discussed its survival mechanisms. METHODS: A lateral mandibular neck skin flap shaped like a table tennis racquet with no well-known blood vessels at the narrow pedicle was designed in 31 cases to repair tissue defects. Among them, there were 8 cases of skin carcinoma in the frontotemporal area and 23 cases of skin carcinoma in the cheek. The flap area was 8.0 × 7.0 cm at maximum and 3.0 × 2.5 cm at minimum, with a pedicle width of 1.0-2.0 cm and a pedicle length of 2.0-6.0 cm. RESULTS: All 31 "table tennis racquet" random skin flaps survived, although there were 3 cases with delayed healing of distal flap bruising. All of them had an ideal local shape after repair with a concealed donor area and inconspicuous scars. CONCLUSIONS: This flap has a "table tennis racquet" shape with a pedicle without well-known blood vessels and has a length-to-width ratio that exceeds that of conventional random flaps, making it unconventional. Because of its long and narrow pedicle, it not only has a large rotation and coverage area but also can be designed away from the defect area, avoiding the defect of no donor tissue being localized near the defect. Overall, this approach is an ideal option for repairing tissue defects after enlarged excision of facial skin carcinoma.


Assuntos
Neoplasias Faciais , Procedimentos de Cirurgia Plástica , Neoplasias Cutâneas , Retalhos Cirúrgicos , Humanos , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias Faciais/cirurgia , Idoso , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/irrigação sanguínea , Resultado do Tratamento , Transplante de Pele/métodos , Adulto , Cicatrização/fisiologia , Idoso de 80 Anos ou mais , Sobrevivência de Enxerto
3.
J Oral Maxillofac Surg ; 81(5): 536-545, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36852757

RESUMO

PURPOSE: Although midazolam is commonly used to sedate patients with dental anxiety, it has shortcomings that reduce the satisfaction of patients and doctors. The aim of this study was therefore to explore the advantages of remimazolam as a sedative. METHODS: The study design was a prospective randomized controlled trial. Patients with dental anxiety and who were to undergo impacted tooth removal were randomized into remimazolam and midazolam groups. They were sedated with remimazolam or midazolam prior to receiving nerve blocker. The predictor variable was the type of sedative, while the primary outcome variables were the onset time, awakening time, recovery time, and postoperative side effects. Secondary outcome variables were the Modified Dental Anxiety Scale score before and after surgery, patient satisfaction and comfort levels scores, and doctor satisfaction level scores. Other variables included the patient demographics and the operation time. Data were analyzed using the Student's t-test, Mann-Whitney test, χ2 test, and two-way repeated measurement ANOVA test (SPSS Version 25.0). RESULTS: A total of 83 patients were included in this study, with 42 randomized to the remimazolam group and 41 to the midazolam group. There were no significant differences between the two groups in terms of demographic features and operation time. Patients in the remimazolam group had significantly shorter onset time, awakening time, and recovery time compared to those in the midazolam group (each P < .001). Postoperative side effects were more frequent in the midazolam group (P < .001). Following surgery, the Modified Dental Anxiety Scale scores in both groups were significantly lower than prior to surgery (P < .001). Satisfaction levels scores for the patients and doctor were higher in the remimazolam group than in the midazolam group (P < .001). CONCLUSIONS: The use of remimazolam results in faster onset, more rapid recovery, and lower incidence of postoperative side effects compared to midazolam, leading to improved satisfaction for patients and doctors. Remimazolam therefore appears to have several advantages over midazolam for the sedation of patients with dental anxiety associated with the removal of impacted teeth.


Assuntos
Midazolam , Dente Impactado , Humanos , Midazolam/uso terapêutico , Dente Impactado/cirurgia , Ansiedade ao Tratamento Odontológico/prevenção & controle , Estudos Prospectivos , Método Duplo-Cego , Hipnóticos e Sedativos/uso terapêutico
4.
World J Surg Oncol ; 21(1): 30, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36721264

RESUMO

OBJECTIVE: According to the different characteristics of patients and cervical lymph node metastasis of oral and oropharyngeal cancer, the marginal mandibular branches of facial nerves were treated by different surgical procedures, and the safety and protective effects of different surgical procedures were investigated. METHODS: One hundred ninety-seven patients with oral and oropharyngeal cancer satisfying the inclusion criteria were selected. According to the different characteristics of patients and cervical metastatic lymph nodes, three different surgical procedures were used to treat the marginal mandibular branches of the facial nerve: finding and exposing the marginal mandibular branches of the facial nerves at the mandibular angles of the platysma flaps, finding and exposing the marginal mandibular branches of facial nerves at the intersections of the distal ends of facial arteries and veins with the mandible, and not exposing the marginal mandibular branches of the facial nerves. The anatomical position, injury, and complications of the marginal mandibular branches of the facial nerves were observed. RESULTS: The marginal mandibular branches of the facial nerves were found and exposed at the mandibular angles of the platysma flaps in 102 patients; the marginal mandibular branches of facial nerves were found and exposed at the intersections of the distal ends of the facial arteries and veins with the mandibles in 64 patients; the marginal mandibular branches of facial nerves were not exposed in 31 patients; among them, four patients had permanent injury of the marginal mandibular branches of the facial nerves, and temporary injury occurred in seven patients. There were statistically significant differences in the protection of the mandibular marginal branch of the facial nerve among the three different surgical methods (P = 0.0184). The best protective effect was to find and expose the mandibular marginal branch of the facial nerve at the mandibular angle of the platysma muscle flap, and the injury rate was only 2.94%. CONCLUSION: The three different surgical procedures were all safe and effective in treating the marginal mandibular branches of the facial nerves, the best protective effect was to find and expose the mandibular marginal branch of the facial nerve at the mandibular angle of the platysma muscle flap.


Assuntos
Nervo Facial , Neoplasias Orofaríngeas , Humanos , Excisão de Linfonodo , Neoplasias Orofaríngeas/cirurgia , Linfonodos/cirurgia , Metástase Linfática
5.
Surg Endosc ; 36(11): 8202-8213, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35536485

RESUMO

BACKGROUND AND AIMS: The main limitation of plastic stents is the relatively short stent patency due to occlusion. We designed enteral extended biliary stents with lengths of 26 cm (EEBS-26 cm) and 30 cm (EEBS-30 cm) to prolong stent patency. This study aimed to compare patency among EEBS-26 cm, EEBS-30 cm, and conventional plastic biliary stent (CPBS). METHODS: A single-center prospective randomized controlled study was conducted. Eligible patients were randomized into the EEBS-26 cm, EEBS-30 cm, and CPBS groups, respectively. All patients were followed up every 3 months until stent occlusion, patient death, or at 12-month follow-up. The primary outcome was stent patency. The secondary outcomes included stent occlusion rate, patient survival, mortality, the rate of technical success, and adverse events. RESULTS: Totally 117 patients were randomized into the three groups. There were no significant differences among the three groups in technical success rate, hospital stay, mortality, patient survival, and adverse events (P = 1.000, 0.553, 0.965, 0.302, and 0.427, respectively). Median stent patency durations in the EEBS-26 cm, EEBS-30 cm, and CPBS groups were 156.0 (95% CI 81.6-230.4) days, 81.0 (95% CI 67.9-94.1) days, and 68.0 (95% CI 20.0-116.0) days, respectively (P = 0.002). The EEBS-26 cm group had longer stent patency compared with the CPBS (P = 0.007) and EEBS-30 cm (P < 0.001) groups. The EEBS-26 cm group had lower stent occlusion rates compared with the other groups at 6 months (48.1% vs. 90.5% vs. 82.8%, P = 0.001) and 9 months (75.0% vs. 100.0% vs. 92.9%, P = 0.022). CONCLUSION: EEBS-26 cm has prolonged stent patency and is safe and effective for the alleviation of unresectable extrahepatic malignant biliary obstruction.


Assuntos
Colestase Extra-Hepática , Colestase , Neoplasias , Humanos , Estudos Prospectivos , Plásticos , Resultado do Tratamento , Colestase Extra-Hepática/etiologia , Stents/efeitos adversos , Cuidados Paliativos , Colestase/etiologia , Colestase/cirurgia
6.
Angew Chem Int Ed Engl ; 61(46): e202213178, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36131490

RESUMO

This study presents interesting self-assembly of peapod-like micrometer tubes from a planet-satellite-type supramolecular megamer, which was constructed through the specific host-guest molecular recognition between azobenzene (AZO)-functionalized hyperbranched poly(ethyl-3-oxetanemethanol)-star-poly(ethylene oxide) (HSP-AZO) and ß-cyclodextrin(CD)-based hydrophilic hyperbranched polyglycerol (CD-g-HPG). A peapod-like structure with micrometer-sized tube as the pod and vesicles encapsulated inside as the peas was formed through sequential vesicle entosis, linear association, and fusion processes. Dissipative particle dynamics (DPD) simulations support the structural possibility of the supramolecular peapod formation and its mechanism. UV light irradiation could lead to the disassembly of the peapod-like structure. This study expands the family of supramolecular polymers and opens a new avenue to develop bioinspired complex hierarchical nanoarchitectures at the microscopic level.


Assuntos
Compostos Azo , Planetas , Compostos Azo/química , Interações Hidrofóbicas e Hidrofílicas , Polietilenoglicóis/química
7.
J Neurochem ; 158(4): 980-996, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34033116

RESUMO

Postoperative delirium (POD) is a common post-operative complication in elderly patients that is associated with increased morbidity and mortality. However, the neuropathogenesis of this complication remains unknown. The blood-cerebrospinal fluid barrier (BCB) and brain-blood barrier (BBB) are composed of tight junctions between cells that form physical barriers, and BBB damage plays an important role in the neuropathogenesis of POD. Nevertheless, the role of BCB in POD remains to be elucidated. Herein, we investigated the effect of adenosine A2A receptor (A2A R), a key regulator of the permeability of barriers, on surgery-induced increased permeability of BCB and POD-like behaviors. Open field, buried food, and Y maze tests were used to evaluate behavioral changes in rats after surgery. Levels of tight junction proteins, adherens junction proteins, A2A R, GTP-RhoA, and ROCK2 in the choroid plexus were assessed by western blotting. The concentrations of NaFI and FITC-dextran in the cerebrospinal fluid (CSF) were detected by fluorescence spectrophotometry. Transmission electron microscopy was applied to observe the ultrastructure of the choroid plexus. Surgery/anesthesia decreased the levels of tight junction (e.g., ZO-1, occludin, and claudin1) proteins, increased concentrations of NaFI and FITC-dextran in CSF, damaged the ultrastructure of choroid plexus, and induced POD-like behaviors in rats. An A2A R antagonist alleviated POD-like behaviors in rats. Furthermore, the A2A R antagonist increased the levels of tight junction proteins and restored the permeability of BCB in rats with POD. Fasudil, a selective Rho-associated protein kinase 2 (ROCK2) inhibitor, ameliorated POD-like behaviors induced by A2A R activation. Moreover, fasudil also abolished the increased levels of GTP-RhoA/ROCK2, decreased levels of tight junction proteins, and increased permeability of BCB caused by A2A R activation. Our findings demonstrate that A2A R might participate in regulating BCB permeability in rats with POD via the RhoA/ROCK2 signaling pathway, which suggests the potential of A2A R as a therapeutic target for POD.


Assuntos
Antagonistas do Receptor A2 de Adenosina/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Delírio/tratamento farmacológico , Delírio/psicologia , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/psicologia , Receptor A2A de Adenosina/efeitos dos fármacos , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/uso terapêutico , Animais , Plexo Corióideo/patologia , Delírio/induzido quimicamente , Feminino , Aprendizagem em Labirinto/efeitos dos fármacos , Permeabilidade , Ratos , Ratos Sprague-Dawley , Fluoreto de Sódio/líquido cefalorraquidiano , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/efeitos dos fármacos
8.
Nat Chem Biol ; 15(1): 34-41, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30510190

RESUMO

Bacterial biofilms can be programmed to produce living materials with self-healing and evolvable functionalities. However, the wider use of artificial biofilms has been hindered by limitations on processability and functional protein secretion capacity. We describe a highly flexible and tunable living functional materials platform based on the TasA amyloid machinery of the bacterium Bacillus subtilis. We demonstrate that genetically programmable TasA fusion proteins harboring diverse functional proteins or domains can be secreted and can assemble into diverse extracellular nano-architectures with tunable physicochemical properties. Our engineered biofilms have the viscoelastic behaviors of hydrogels and can be precisely fabricated into microstructures having a diversity of three-dimensional (3D) shapes using 3D printing and microencapsulation techniques. Notably, these long-lasting and environmentally responsive fabricated living materials remain alive, self-regenerative, and functional. This new tunable platform offers previously unattainable properties for a variety of living functional materials having potential applications in biomaterials, biotechnology, and biomedicine.


Assuntos
Bacillus subtilis/fisiologia , Materiais Biocompatíveis/química , Biofilmes , Bacillus subtilis/genética , Proteínas de Bactérias/genética , Materiais Biocompatíveis/metabolismo , Biodegradação Ambiental , Composição de Medicamentos , Elasticidade , Engenharia Genética/métodos , Nanopartículas/química , Paraoxon/metabolismo , Impressão Tridimensional , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
9.
J Craniofac Surg ; 32(1): 179-183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33196618

RESUMO

BACKGROUND: With aging, the facial contour shows a double-concave deformity. Conventional facial contouring procedure, including face lifting and fat grafting, cannot yield a smooth facial contour line. This study was the first to propose a combination of reduction malarplasty and 2nd-stage autologous fat grafting so as to achieve the aesthetic goals of facial contour rejuvenation. METHODS: The study group comprised patients seeking facial contour rejuvenation from January 2017 to May 2018 (28 patients: 28 females and 0 males) at the Department of Plastic Surgery, Tian Tan Pu Hua Hospital. All of the cases underwent bilateral malarplasty with 2nd-stage autologous facial fat grafting. Radiologic and photographic documentation was completed preoperatively. The mean follow-up period was 12 months. Patients' pre-op photographs and 3 months follow-up pictures were blindly assessed. RESULTS: Most of the patients were satisfied with their results after 1-time fat grafting. Eleven patients demanded re-injection after the 1st fat grafting in temporal area, and 6 patients demanded 3rd time fat grafting in temporal area. Eleven patients demanded re-injection insubmalar area, and 8 patients demanded 3rd time fat grafting in submalar area. Meanwhile, 9 of those patients underwent fat grafting in other sites other than temporal and submalar region. The amount of fat injected was also recorded in this study. The appearance of double-concave deformity was greatly improved in all cases. Complications included infection (3.6%), hematoma (7.1%), and malar prominence relapse (7.1%), and so on. CONCLUSION: Reduction malarplasty combined with several times of fat grafting could effectively overcome the malar prominence and soft tissue deflation. Complications were minimal after these procedures. Therefore, this technique is useful to restore the youthful facial contour in Asian patients with aging double-concave deformity.


Assuntos
Procedimentos de Cirurgia Plástica , Ritidoplastia , Tecido Adiposo , Estética Dentária , Feminino , Humanos , Masculino , Rejuvenescimento
10.
J Craniofac Surg ; 32(3): 883-887, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33038180

RESUMO

ABSTRACT: This study summarized the literature regarding the application of pre-bent titanium miniplates in orthognathic surgery and evaluated the extra deformation of the manually pre-bent titanium miniplates via finite element analysis for acquiring higher surgical accuracy. The literature was reviewed with a chart. Three models of titanium miniplates with different thicknesses (1.0 mm, 0.8 mm, 0.6 mm) were created using COMSOL Multiphysics software for biomechanical behavior analysis. The 3 models were virtually bent into 5 angles (15 degree, 30 degree, 45 degree, 60 degree, 80 degree). respectively to simulate the preoperative virtual bending, then to simulate the practical manual bending via finite element analysis. The stresses and displacements of these models were recorded. The models from virtual bending simulation and manual bending simulation were registered to analyze the deviations. The results showed that the maximum stress and the displacement deviations between the virtual bending models and the manual bending models increased with the thickness and bending angle of the pre-bent miniplate models. To improve the surgical accuracy, measures should be applied to the manually pre-bent titanium miniplates to reduce the extra deformation when the plate being thicker and the bending angle being larger.


Assuntos
Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Placas Ósseas , Análise de Elementos Finitos , Fixação Interna de Fraturas , Humanos , Estresse Mecânico , Titânio
11.
Waste Manag Res ; 39(9): 1210-1213, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33832373

RESUMO

Bioplastics are developed to replace oil-derived plastics due to the high consumption of oil and related environmental impacts of oil-derived plastics. It was predicted that bioplastics can potentially replace 94% of conventional plastic production. With their increasing market share, more bioplastics will end in conventional post-consumer plastic waste streams. Although part of bioplastics is biodegradable and could be biologically decomposed, mechanical recycling achieves higher ecological benefits mainly because of its low pollution risk and the reduction in requirement for virgin feedstock. In this study, the classification of lightweight packaging waste with inflow of bioplastics, more specifically polylactic acid (PLA), was analysed with near-infrared spectroscopy to evaluate the influence of bioplastics on sorting processes of conventional plastics. Besides which, the sortability of PLA was determined through investigating the physical and the spectroscopic characteristics of both non-degraded and degraded PLA. The results show that the classification of all the materials was possible with a pixel-based accuracy of higher than 97.4% and PLA does not influence the sorting process of conventional plastics regarding detection and classification. Furthermore, the sorting of PLA from post-consumer waste is possible, which makes further recycling theoretically achievable.


Assuntos
Plásticos , Poliésteres , Embalagem de Produtos , Reciclagem
12.
J Am Chem Soc ; 142(10): 4565-4569, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32100539

RESUMO

Combining synthetic chemistry and biocatalysis is a promising but underexplored approach to intracellular catalysis. We report a strategy to codeliver a single-chain nanoparticle (SCNP) catalyst and an exogenous enzyme into cells for performing bioorthogonal reactions. The nanoparticle and enzyme reside in endosomes, creating engineered artificial organelles that manufacture organic compounds intracellularly. This system operates in both concurrent and tandem reaction modes to generate fluorophores or bioactive agents. The combination of SCNP and enzymatic catalysts provides a versatile tool for intracellular organic synthesis with applications in chemical biology.


Assuntos
Nanopartículas/metabolismo , beta-Galactosidase/metabolismo , Antineoplásicos/farmacologia , Células Artificiais/metabolismo , Catálise , Engenharia Celular/métodos , Complexos de Coordenação/química , Complexos de Coordenação/metabolismo , Cumarínicos/síntese química , Doxorrubicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Endossomos/metabolismo , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Nanopartículas/química , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacologia , Estudo de Prova de Conceito , Rodaminas/síntese química , Rutênio/química , Estilbenos/farmacologia
13.
J Am Chem Soc ; 142(32): 13966-13973, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32664734

RESUMO

Synthetic polymer scaffolds may serve as gatekeepers preventing the adhesion of biomacromolecules. Herein, we use gating to develop a copper-containing single-chain nanoparticle (SCNP) catalyst as an artificial "clickase" that operates selectively on small molecules that are able to penetrate the polymeric shell. Whereas the analogous clickase with surface ammonium groups performs highly efficient copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC) reactions on both alkynylated proteins and small molecule substrates, the new SCNP clickase with polyethylene glycol (PEG) groups is only active on small molecules. Further, the new SCNP resists uptake by cells allowing extracellular click chemistry to be performed. We describe two proof of principle applications that illustrate the utility of the bioorthogonal activity. First, the SCNP catalyst is able to screen for ligands that bind proteins, including proteolysis targeting chimera (PROTAC)-like molecules. Second, the nonmembrane permeable SCNP can efficiently catalyze the click reaction extracellularly, thereby enabling in situ anticancer drug synthesis and screening without the catalyst perturbing intracellular functions.


Assuntos
Polímeros/química , Bibliotecas de Moléculas Pequenas/química , Anidrase Carbônica II/química , Anidrase Carbônica II/metabolismo , Catálise , Química Click , Cobre/química , Células HeLa , Humanos , Ligantes , Nanopartículas Metálicas/química , Modelos Moleculares , Estrutura Molecular , Polímeros/síntese química
14.
Phys Chem Chem Phys ; 22(39): 22324-22331, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33020779

RESUMO

CNT-based reverse osmosis membranes have long been regarded as one of the most promising candidates for water desalination. However, it is a pity that there is no complete understanding of the exact role of CNTs in those nanocomposite membranes. To address this issue, three atomistic models of PA (pure polyamide membrane), PA-CNT1 (polyamide nanocomposite membrane with an embedded carbon nanotube oriented vertical to the membrane surface) and PA-CNT2 (polyamide nanocomposite with an embedded carbon nanotube oriented parallel to the membrane surface) were constructed respectively in this work. Then, equilibrium molecular dynamics (EMD) and non-equilibrium molecular dynamics (NEMD) simulations were conducted to investigate the structure and water dynamics in these three models. The EMD simulations revealed a better stacking of the PA matrix due to the addition of the CNT and this impact was more significant in PA-CNT1 than in PA-CNT2. Meanwhile, PA matrix near the mouth of the CNT was found to behave as an obstruction that hindered the exchange of water molecules inside and outside the CNT. In NEMD simulations, we found that water molecules were guided away from the CNT because of the better stacked surrounding PA matrix. The partially covered CNT might not help to increase water flux in PA-CNT1 while guided water molecules and the smaller polymer region afftected by the CNT contributed to a relatively high flux in PA-CNT2. The current work might serve as a comprehensive understanding of the role of CNTs in the reverse osmosis process.

15.
J Craniofac Surg ; 31(8): 2193-2198, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33136853

RESUMO

The aim of this study is to evaluate the osteogenesis around titanium implant and in bone defect or fracture in jaw bones and long bones in ovariectomized (OVX) animal models. The literature on the osteogenesis around titanium implant and in bone defect or fracture in jaw bones and long bones was reviewed with charts. Fourty-eight rats were randomly divided into OVX group with ovariectomy and SHAM (sham-surgery) group with sham surgery. Titanium implants were inserted in the right mandibles and tibiae; bone defects were created in the left mandibles and tibiae. Two-week postoperatively, mandibles and tibiae of 8 rats were harvested and examined by hematoxylin and eosin staining and histological analysis; 4-week postoperatively, all mandibles and tibiae were harvested and examined by Micro-CT and histological analysis. A total of 52 articles were included in this literature review. Tibial osteogenesis around titanium implant and in bone defect in OVX group were significantly decreased compared with SHAM group. However, osteogenesis differences in the mandible both around titanium implant and in bone defect between groups were not statistically significant. OVX-induced osteoporosis suppresses osteogenesis around titanium implant and in the bone defect or fracture in long bones significantly while has less effect on that in the jaw bones.


Assuntos
Implantes Experimentais/efeitos adversos , Arcada Osseodentária/efeitos dos fármacos , Tíbia/efeitos dos fármacos , Titânio/farmacologia , Animais , Feminino , Procedimentos Cirúrgicos Ortognáticos , Osteogênese/efeitos dos fármacos , Osteoporose/induzido quimicamente , Osteoporose/patologia , Ovariectomia , Ratos , Tíbia/cirurgia
16.
J Am Chem Soc ; 141(24): 9693-9700, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31124359

RESUMO

Recent work has shown that polymeric catalysts can mimic some of the remarkable features of metalloenzymes by binding substrates in proximity to a bound metal center. We report here an unexpected role for the polymer: multivalent, reversible, and adaptive binding to protein surfaces allowing for accelerated catalytic modification of proteins. The catalysts studied are a group of copper-containing single-chain polymeric nanoparticles (CuI-SCNP) that exhibit enzyme-like catalysis of the copper-mediated azide-alkyne cycloaddition reaction. The CuI-SCNP use a previously observed "uptake mode", binding small-molecule alkynes and azides inside a water-soluble amphiphilic polymer and proximal to copper catalytic sites, but with unprecedented rates. Remarkably, a combined experimental and computational study shows that the same CuI-SCNP perform a more efficient click reaction on modified protein surfaces and cell surface glycans than do small-molecule catalysts. The catalysis occurs through an "attach mode" where the SCNPs reversibly bind protein surfaces through multiple hydrophobic and electrostatic contacts. The results more broadly point to a wider capability for polymeric catalysts as artificial metalloenzymes, especially as it relates to bioapplications.


Assuntos
Cobre/química , Proteínas de Membrana/química , Nanopartículas/química , Polímeros/química , Polissacarídeos/química , Alcinos/química , Animais , Azidas/química , Catálise , Bovinos , Linhagem Celular Tumoral , Química Click , Reação de Cicloadição , Humanos , Simulação de Dinâmica Molecular
17.
J Gene Med ; 21(10): e3122, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31420900

RESUMO

BACKGROUND: Tumor protein p63 (TP63)-related disorders can be divided into at least six categories, including ectrodactyly-ectodermal dysplasia-cleft lip/palate syndrome 3 (EEC syndrome 3), ankyloblepharon-ectodermal defects-cleft lip/palate syndrome (AEC syndrome), acro-dermo-ungual-lacrimal-tooth syndrome (ADULT syndrome), limb-mammary syndrome (LMS), Rapp-Hodgkin syndrome (RHS) and split-hand/foot malformation 4 (SHFM4), and are all a result of heterozygous mutations of TP63. The phenotypes of TP63-related disorders broadly involve ectodermal dysplasias, acromelic malformation and orofacial cleft. SHFM and hypodontia are prominent clinical manifestations of TP63-related disorders. METHODS: The present study investigated a family with SHFM and hypodontia; determined the sequences of DLX5, WNT8B, WNT10B, BHLHA9, CDH3, DYNC1I1 and FGFR1; and performed single nucleotide polymorphism-array analysis. We detected the mutation by multiple sequence alignments and a bioinformatic prediction. RESULTS: We identified a novel missense mutation of TP63 (c.1010G>T; R337L) in the family without mutations of DLX5, WNT8B, WNT10B, BHLHA9, CDH3, DYNC1I1, FGFR1 and copy number variants causing SHFM. CONCLUSIONS: A mutation of TP63 (c.1010G>T; R337L) leads to SHFM with hypodontia. The identification of this mutation expands the spectrum of known TP63 mutations and also may contribute to novel approaches for the genetic diagnosis and counseling of families with TP63-related disorders.


Assuntos
Alelos , Substituição de Aminoácidos , Anodontia/diagnóstico , Anodontia/genética , Deformidades Congênitas dos Membros/diagnóstico , Deformidades Congênitas dos Membros/genética , Mutação , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Adulto , Criança , Biologia Computacional , Análise Mutacional de DNA , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Linhagem , Fenótipo , Polimorfismo de Nucleotídeo Único , Radiografia , Síndrome
18.
Exp Cell Res ; 371(1): 50-62, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30055135

RESUMO

DESI2 is a novel pro-apoptotic gene. We previously reported that DESI2 overexpression induces S phase arrest and apoptosis by activating checkpoint kinases. This work was to test whether the combination of endostatin, an endogenous antiangiogenic inhibitor, with DESI2 could improve the therapy efficacy in vitro and in vivo. The recombinant plasmid co-expressing DESI2 and endostatin was encapsulated with DOTAP/Cholesterol cationic liposome. Mice bearing CT26 colon carcinoma and LL2 lung cancer were treated with the DNA-liposome complex. We found that, in vitro, the combination of DESI2 and endostatin more efficiently inhibited proliferation of CT26, LL2, HCT116 and A549 cancer cells via apoptosis, as assessed by MTT assay, colony-formation assays, flow cytometric analysis, hoechst staining and activation of caspase-3, respectively. In addition, DESI2 overexpression caused up-regulation of RPS7, a substrate of DESI2 deubiquitination. Furthermore, siRNA targeting RPS7 partially abrogated, whereas RPS7 overexpression enhanced DESI2-induced inhibition of cell proliferation. Importantly, the combination also caused DNA lesions accumulation, which further promotes apoptosis. Mechanistic rationale suggested that endostatin first inhibits DNA-PKcs kinase, and partly abrogated DESI2-induced phosphorylation of DNA-PKcs, leading to increase of DNA damage, then contributes to DESI2-induced apoptosis. In vivo, the combined gene therapy more significantly inhibited tumor growth and efficiently prolonged the survival of tumor bearing mice than mono therapy. The improved antitumor effect was associated with inhibition of cell proliferation via apoptosis, as analyzed by TUNEL assay and PCNA immunostaining. The combination also inhibited angiogenesis, as assessed by alginate-encapsulated tumor cell assay and CD31 staining. Our data suggest that the combined gene therapy of DESI2 and endostatin can significantly enhance the antitumor activity as a DNA lesions accumulator, apoptosis inducer and angiogenesis inhibitor. The present study may provide a novel method for the treatment of cancer.


Assuntos
Carbono-Nitrogênio Liases/genética , Neoplasias do Colo/genética , Endostatinas/genética , Regulação Neoplásica da Expressão Gênica , Terapia Genética/métodos , Neoplasias Pulmonares/genética , Plasmídeos/metabolismo , Células A549 , Inibidores da Angiogênese/química , Inibidores da Angiogênese/metabolismo , Animais , Apoptose/genética , Carbono-Nitrogênio Liases/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Proliferação de Células , Colesterol/química , Colesterol/metabolismo , Neoplasias do Colo/mortalidade , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Fragmentação do DNA , Endostatinas/metabolismo , Ácidos Graxos Monoinsaturados/química , Ácidos Graxos Monoinsaturados/metabolismo , Feminino , Células HCT116 , Humanos , Lipossomos/administração & dosagem , Lipossomos/química , Lipossomos/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Camundongos , Camundongos Endogâmicos C57BL , Plasmídeos/administração & dosagem , Plasmídeos/química , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas Ribossômicas/antagonistas & inibidores , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Transdução de Sinais , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Acta Pharmacol Sin ; 40(4): 539-545, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29921887

RESUMO

Tumor-targeted drug delivery systems (Tt-DDSs) are proposed as a promising strategy for cancer care. However, the dense collagen network in tumors stroma significantly reduces the penetration and efficacy of Tt-DDS. In order to investigate the effect of asiatic acid (AA) on antitumor effect of pegylated liposomal doxorubicin (PLD) by attenuating stroma-collagen, colon cancer xenograft mice (SW620 cell line) were treated by PLD, AA, or combined regimes, respectively; the collagen levels were estimated by Sirius red/fast green dual staining and immunohistochemistry (IHC) staining; the intratumor exposure of doxorubicin was visualized by ex vivo fluorescence imaging and quantified by HPLC/MS analysis. In addition, the impact of AA on collagen synthesis of fibroblast cell (HFL-1) and cytotoxic effect of PLD and doxorubicin to cancer cell (SW620) were studied in vitro. In the presence of AA (4 mg/kg), the intratumor collagen level was restricted in vivo (reduced by 22%, from 4.14% ± 0.30% to 3.24% ± 0.25%, P = 0.051) and in vitro. Subsequently, doxorubicin level was increased by ~30%. The antitumor activity of PLD was significantly improved (57.3% inhibition of tumor growth and 44% reduction in tumor weight) by AA combination. Additionally, no significant improvement in cytotoxic effect of PLD or doxorubicin induced by AA was observed. In conclusion, AA is a promising sensitizer for tumor treatment by enhancing intratumor drug exposure via stromal remodeling.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/análogos & derivados , Sistemas de Liberação de Medicamentos , Triterpenos Pentacíclicos/farmacologia , Animais , Antibióticos Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Colágeno/análise , Colágeno/antagonistas & inibidores , Colágeno/metabolismo , Relação Dose-Resposta a Droga , Doxorrubicina/química , Doxorrubicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Imagem Óptica , Triterpenos Pentacíclicos/química , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Relação Estrutura-Atividade
20.
J Opt Soc Am A Opt Image Sci Vis ; 36(9): 1585-1590, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31503855

RESUMO

The conventional concave diffraction grating (CDG) is commonly operated as a coarse demultiplexer device due to significant increases in the chip size and cost for large dispersion. Compact dense wavelength multiplexing is proposed and demonstrated by utilizing a dual-input CDG integrated with dielectric multidirectional reflectors. This structure allows light beams incident from two different directions to be efficiently reflected and get diffracted into the respective output waveguides by a single grating, thus creating a doubled channel number and halved channel spacing while keeping the chip size constant. The dielectric multidirectional reflector is designed by one-dimensional photonic crystal theory and used as the grating tooth to provide high reflectivities over a wide angular range. Simulation results suggest that the dual-input CDG with incident angles of 1° and 6° exhibits efficiency of more than $-0.564 \,\,{\rm{dB}} $ and crosstalk less than $-21.2 \,\,{\rm{dB}} $.

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