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1.
Environ Sci Technol ; 57(48): 19663-19677, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37948609

RESUMO

A lack of mechanistic understanding of nanomaterial interactions with plants and algae cell walls limits the advancement of nanotechnology-based tools for sustainable agriculture. We systematically investigated the influence of nanoparticle charge on the interactions with model cell wall surfaces built with cellulose or pectin and performed a comparative analysis with native cell walls of Arabidopsis plants and green algae (Choleochaete). The high affinity of positively charged carbon dots (CDs) (46.0 ± 3.3 mV, 4.3 ± 1.5 nm) to both model and native cell walls was dominated by the strong ionic bonding between the surface amine groups of CDs and the carboxyl groups of pectin. In contrast, these CDs formed weaker hydrogen bonding with the hydroxyl groups of cellulose model surfaces. The CDs of similar size with negative (-46.2 ± 1.1 mV, 6.6 ± 3.8 nm) or neutral (-8.6 ± 1.3 mV, 4.3 ± 1.9 nm) ζ-potentials exhibited negligible interactions with cell walls. Real-time monitoring of CD interactions with model pectin cell walls indicated higher absorption efficiency (3.4 ± 1.3 10-9) and acoustic mass density (313.3 ± 63.3 ng cm-2) for the positively charged CDs than negative and neutral counterparts (p < 0.001 and p < 0.01, respectively). The surface charge density of the positively charged CDs significantly enhanced these electrostatic interactions with cell walls, pointing to approaches to control nanoparticle binding to plant biosurfaces. Ca2+-induced cross-linking of pectin affected the initial absorption efficiency of the positively charged CD on cell wall surfaces (∼3.75 times lower) but not the accumulation of the nanoparticles on cell wall surfaces. This study developed model biosurfaces for elucidating fundamental interactions of nanomaterials with cell walls, a main barrier for nanomaterial translocation in plants and algae in the environment, and for the advancement of nanoenabled agriculture with a reduced environmental impact.


Assuntos
Arabidopsis , Nanopartículas , Eletricidade Estática , Celulose/metabolismo , Plantas/metabolismo , Arabidopsis/metabolismo , Pectinas/metabolismo , Parede Celular/metabolismo
2.
Proteins ; 89(10): 1365-1375, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34085313

RESUMO

The coxsackievirus A16 (CVA16) is a highly contagious virus that causes the hand, foot, and mouth disease, which seriously threatens the health of children. At present, there are still no available antiviral drugs or effective treatments against the infection of CVA16, and thus it is of great significance to develop anti-CVA16 vaccines. However, the intrinsic uncoating property of the capsid may destroy the neutralizing epitopes and influence its immunogenicity, which hinders the vaccine developments. In the present work, the functional-quantity-based elastic network model analysis method developed by our group was extended to combine with group theory to investigate the uncoating motions of the CVA16 capsid, and then the functionally key residues controlling the uncoating motions were identified by our functional-quantity-based perturbation method. Several motion modes encoded in the topological structure of the capsid were revealed to be responsible for the uncoating of CVA16 particle. These modes predominantly contribute to the fluctuation of the gyration radius of the capsid. Then, by using the perturbation method, four clusters of key sites involved in the uncoating motions were identified, whose perturbations induce significant changes in the fluctuation of the gyration radius. These key residues are mainly located at the 2-fold channels, the quasi 3-fold channels, the bottom of the canyons, and the inter-subunit interfaces around the 3-fold axes. Our studies are helpful for better understanding the uncoating mechanism of the CVA16 capsid and provide potential target sites to prevent the uncoating motions, which is valuable for the vaccine design against CVA16.


Assuntos
Proteínas do Capsídeo/química , Capsídeo/química , Infecções por Coxsackievirus/virologia , Enterovirus/metabolismo , Humanos
3.
BMC Oral Health ; 19(1): 164, 2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31345197

RESUMO

BACKGROUND: Otodental syndrome is an exceptionally rare autosomal dominant condition characterized by a delayed eruption of posterior teeth, globodontia, lisping, and sensorineural hearing loss. In this case report, we reported a 3-year-old Chinese boy with the otodental syndrome. CASE PRESENTATION: A 3-year-old Chinese boy was referred to our hospital with complaint of no eruption of primary canines and molars. Three years follow-up showed lately erupted bulbous primary canines with hypoplastic enamel spot, globe-shaped primary molars and sensorineural hearing loss at 4 and a half-year-old age. We diagnosed otodental syndrome in the patient's mother with hearing loss at 16-year-old age. Gene sequencing and analysis of deafness-related genes GJB2, GJB3, SLC26A4, and mtDNA did not reveal any mutation or SNPs in the patient and his mother. CONCLUSIONS: This case report highlights the importance of detailed medical, dental, and family history examination, as well as multi-disciplinary teamwork for diagnosis and treatment of otodental syndrome.


Assuntos
Transtornos Cromossômicos/diagnóstico , Coloboma/diagnóstico , Perda Auditiva Neurossensorial/diagnóstico , Anormalidades Dentárias/diagnóstico , Anormalidades Múltiplas/genética , Adolescente , Povo Asiático , Pré-Escolar , Deleção Cromossômica , Cromossomos Humanos Par 11 , Coloboma/genética , Perda Auditiva Neurossensorial/genética , Humanos , Masculino , Mutação , Odontoma/diagnóstico , Odontoma/genética , Anormalidades Dentárias/genética
4.
Neurobiol Dis ; 108: 73-82, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28823935

RESUMO

Intravenously infused synthetic 500nm nanoparticles composed of poly(lactide-co-glycolide) are taken up by blood-borne inflammatory monocytes via a macrophage scavenger receptor (macrophage receptor with collagenous structure), and the monocytes no longer traffic to sites of inflammation. Intravenous administration of the nanoparticles after experimental spinal cord injury in mice safely and selectively limited infiltration of hematogenous monocytes into the injury site. The nanoparticles did not bind to resident microglia, and did not change the number of microglia in the injured spinal cord. Nanoparticle administration reduced M1 macrophage polarization and microglia activation, reduced levels of inflammatory cytokines, and markedly reduced fibrotic scar formation without altering glial scarring. These findings thus implicate early-infiltrating hematogenous monocytes as highly selective contributors to fibrosis that do not play an indispensable role in gliosis after SCI. Further, the nanoparticle treatment reduced accumulation of chondroitin sulfate proteoglycans, increased axon density inside and caudal to the lesion site, and significantly improved functional recovery after both moderate and severe injuries to the spinal cord. These data provide further evidence that hematogenous monocytes contribute to inflammatory damage and fibrotic scar formation after spinal cord injury in mice. Further, since the nanoparticles are simple to administer intravenously, immunologically inert, stable at room temperature, composed of an FDA-approved material, and have no known toxicity, these findings suggest that the nanoparticles potentially offer a practical treatment for human spinal cord injury.


Assuntos
Fatores Imunológicos/administração & dosagem , Nanopartículas/administração & dosagem , Poliglactina 910/administração & dosagem , Traumatismos da Medula Espinal/tratamento farmacológico , Administração Intravenosa , Animais , Axônios/efeitos dos fármacos , Axônios/imunologia , Axônios/patologia , Tamanho Celular , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Cicatriz/tratamento farmacológico , Cicatriz/imunologia , Cicatriz/patologia , Modelos Animais de Doenças , Feminino , Fibrose/tratamento farmacológico , Fibrose/imunologia , Fibrose/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/patologia , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/imunologia , Microglia/patologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Monócitos/patologia , Atividade Motora/efeitos dos fármacos , Recuperação de Função Fisiológica/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Medula Espinal/imunologia , Medula Espinal/patologia , Traumatismos da Medula Espinal/imunologia , Traumatismos da Medula Espinal/patologia
5.
Acta Odontol Scand ; 75(3): 161-165, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28121195

RESUMO

OBJECTIVE: The objective of this study is to evaluate the relationship between tooth agenesis and the occurrence of other dental anomalies in children and adolescents. MATERIAL AND METHODS: Panoramic radiographs of 195 subjects with tooth agenesis, except for the third molar, were retrospectively examined and compared with a non-agenesis control group of 600 subjects. Their ages ranged from 7 to 15 years. Panoramic and periapical radiographs were used to analyze the presence of other associated dental anomalies. The occurrences of these anomalies were compared with those in the non-agenesis group. RESULTS: Subjects with tooth agenesis showed a significantly higher prevalence of a small maxillary lateral incisor (17.7%), distoangulation of the mandibular second premolar (6.5%), delayed development of a permanent tooth (10.8%), and hypo-occlusion of a primary molar (11.8%). In contrast, the prevalence of a supernumerary tooth was higher in the control group, and no difference was observed in the prevalence of ectopic eruption of a first molar. According to the agenesis area, microdontia of the maxillary lateral incisors occurred more often in patients with anterior or premolar agenesis than in the molar agenesis groups. Distoangulation of the mandibular second premolars, delayed tooth development, and hypo-occlusion of the primary molars were associated with premolar tooth agenesis. CONCLUSIONS: A small maxillary lateral incisor, distoangulation of the mandibular second premolar, delayed development of a permanent tooth, and hypo-occlusion of a primary molar were frequently associated with tooth agenesis, providing additional evidence of a genetic interrelationship in the causes of these dental anomalies.


Assuntos
Anodontia/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Anormalidades Dentárias/diagnóstico por imagem , Adolescente , Anodontia/epidemiologia , Criança , Oclusão Dentária , Dentição Permanente , Feminino , Humanos , Incisivo/anormalidades , Masculino , Dente Molar/anormalidades , Radiografia Panorâmica , Anormalidades Dentárias/epidemiologia , Erupção Ectópica de Dente/diagnóstico por imagem , Dente Supranumerário/diagnóstico por imagem
6.
J Cosmet Dermatol ; 23(1): 236-243, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37415450

RESUMO

BACKGROUND: Collagen is a major component of the extracellular matrix that supports the epidermal layers of the skin; thus, many strategies have been made to enhance the topical delivery of collagen for antiaging purposes. In addition, our previous study indicated that liposome can help the penetration of active ingredients into the skin. AIMS: To produce stable collagen-encapsulated liposomes to improve the topical delivery of collagen. METHODS: Collagen-encapsulated liposomes were fabricated using high-pressure homogenization method. The colloidal stability and adhesion ability were confirmed using dynamic light scattering, and spectrofluorophotometer, respectively. Keratinocyte differentiations of 3D skin before and after treatment with collagen-encapsulated liposomes were confirmed by real-time PCR. RESULTS: In comparison with native collagen, collagen-encapsulated liposomes enhanced collagen retention in artificial membranes by twofold, even after repeated washings with water. In addition, real-time PCR results indicated that 3D skin treated with collagen-encapsulated liposomes exhibited higher levels of collagen, keratin, and involucrin, even after ethanol treatment. CONCLUSION: Liposomes could serve as efficient delivery vehicles for collagen, thereby enhancing its antiaging effects.


Assuntos
Lipossomos , Pele , Humanos , Colágeno
7.
Biochem Biophys Res Commun ; 435(3): 361-6, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23669037

RESUMO

In this study, we developed a 2-step delivery system to enhance transdermal permeation of quercetin and its glycoside rutin, an antioxidant. Liposome-in-hydrogel complex systems were prepared by incorporating ceramide liposomes, which consist of biocompatible lipid membranes, into cellulose hydrogel. We evaluated the encapsulation efficiency, in vitro release behavior, and skin permeability of formulations that remained stable for over 3 weeks. Rutin had greater encapsulation efficiency and better in vitro release properties than quercetin. However, quercetin demonstrated greater skin permeability than rutin. We also found that liposome-in-hydrogel complex systems (quercetin, 67.42%; rutin 59.82%) improved skin permeability of quercetin and rutin compared to control (phosphate buffer, pH 7.4) (quercetin, 2.48%; rutin, 1.89%) or single systems of hydrogel (quercetin, 31.77%; rutin, 26.35%) or liposome (quercetin, 48.35%; rutin, 37.41%). These results indicate that liposome-in-hydrogel systems can function as potential drug delivery systems to enhance transdermal permeation of the water-insoluble antioxidants quercetin and rutin.


Assuntos
Antioxidantes/administração & dosagem , Antioxidantes/farmacocinética , Sistemas de Liberação de Medicamentos , Quercetina/administração & dosagem , Quercetina/farmacocinética , Rutina/administração & dosagem , Rutina/farmacocinética , Administração Cutânea , Animais , Ceramidas , Feminino , Hidrogéis , Lipossomos , Teste de Materiais , Camundongos , Camundongos Endogâmicos ICR , Quercetina/metabolismo , Rutina/metabolismo
8.
Biomedicines ; 11(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37760883

RESUMO

Oral cancer is a malignant tumor that primarily affects areas such as the lips, tongue, buccal mucosa, salivary gland, and gingiva and has a very high malignancy. Piperlongumine (PL), isolated from long pepper (Piper longum L.), is a natural alkaloid with pharmacological effects, such as anti-inflammatory and anti-atherosclerotic effects. The effect and mechanism of PL in oral cancer cell lines has not been explored. Therefore, this study aimed to investigate the mechanism of anticancer effects of PL in the human oral cancer cell lines MC-3 and HSC-4 in vitro. This study demonstrated that PL inhibits cell proliferation by inducing apoptosis and autophagy in human oral cancer cell lines, which was confirmed by the levels of apoptosis- and autophagy-related proteins through Western blotting. Moreover, the pharmacological blockade of autophagy activation by hydroxychloroquine (HCQ), an autophagy inhibitor, significantly improved PL-induced apoptosis in MC-3 cells, suggesting a cytoprotective effect. In addition, activation of the mitogen-activated protein kinase (MAPK) signaling pathway contributed to PL-induced apoptosis. Collectively, the study suggested that combining an autophagy inhibitor with PL treatment can exert effective anticancer properties in oral cancer cells by inducing apoptosis and cytoprotective autophagy via the JNK-mediated MAPK pathway.

9.
World J Clin Cases ; 10(16): 5317-5323, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35812652

RESUMO

BACKGROUND: Crouzon syndrome (CS; OMIM 123500) is an autosomal dominant inherited craniofacial disorder caused by mutations in the fibroblast growth factor receptor 2 (FGFR2) gene. CS is characterized by craniofacial dysostosis, exophthalmos, and facial anomalies with hypoplastic maxilla and relative mandibular prognathism. CASE SUMMARY: Our report involves a 6-year-old fraternal twin boy with many caries in the oral cavity who presented with characteristic features of CS based on clinical and radiographic examinations along with Sanger sequencing. The fraternal girl did not show any abnormalities indicating CS. Carious teeth and poor oral hygiene were managed promptly through administering appropriate behavior guidance, orthodontic treatment was planned, and preventive procedures were described. CONCLUSION: CS could occur in a fraternal twin caused by a de novo mutation of the FGFR2 gene. Oral hygiene instruction, preventive programs on oral hygiene, orthodontic treatment, and maxillary osteotomy were required for treatment.

10.
J Cosmet Dermatol ; 21(12): 6822-6829, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36052771

RESUMO

BACKGROUND: Cationic liposomes can enhance the permeability of drugs in 3-D skin. Chitosan is considered a safe material for percutaneous delivery; thus, this study uses chitosan-incorporated cationic liposomes. AIMS: This study investigated the improvement in skin brightness, melanin, and melasma after treatment niacinamide-incorporated chitosan cationic liposomes. METHODS: A skin brightening agent, niacinamide, was formulated into cationic liposomes to facilitate percutaneous absorption and was clinically tested in 21 Korean female subjects. Cationic liposomes were prepared using a high-pressure homogenizer after mixing an oil phase containing lecithin and cholesterol and an aqueous phase containing niacinamide and chitosan. RESULTS: The cationic liposomes exhibited stability over 28 days, with a particle size of 255-275 nm and zeta potential of 10-14 mV. Cationic liposomes containing niacinamide and a control formulation were applied to the left and right side of the face, respectively, twice daily for 28 days. Skin brightness, melanin index, and area of melasma were significantly enhanced where cationic liposomes were used, in comparison with formulations without cationic liposomes, demonstrating a 1.38-2.08-fold improvement. CONCLUSION: Thus, we established that chitosan liposomes augmented the percutaneous absorption of niacinamide and improved the appearance of the skin.


Assuntos
Quitosana , Melanose , Humanos , Feminino , Lipossomos , Melaninas , Niacinamida
11.
Science ; 377(6614): 1561-1566, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36173865

RESUMO

The conversion of polyolefins to monomers would create a valuable carbon feedstock from the largest fraction of waste plastic. However, breakdown of the main chains in these polymers requires the cleavage of carbon-carbon bonds that tend to resist selective chemical transformations. Here, we report the production of propylene by partial dehydrogenation of polyethylene and tandem isomerizing ethenolysis of the desaturated chain. Dehydrogenation of high-density polyethylene with either an iridium-pincer complex or platinum/zinc supported on silica as catalysts yielded dehydrogenated material containing up to 3.2% internal olefins; the combination of a second-generation Hoveyda-Grubbs metathesis catalyst and [PdP(tBu)3(µ-Br)]2 as an isomerization catalyst selectively degraded this unsaturated polymer to propylene in yields exceeding 80%. These results show promise for the application of mild catalysis to deconstruct otherwise stable polyolefins.


Assuntos
Alcenos , Etilenos , Polietileno , Gerenciamento de Resíduos , Alcenos/síntese química , Carbono/química , Catálise , Etilenos/química , Irídio , Platina , Polienos , Polietileno/química , Dióxido de Silício , Gerenciamento de Resíduos/métodos
12.
ACS Nano ; 16(3): 4467-4478, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35179875

RESUMO

Plant abiotic stress induces reactive oxygen species (ROS) accumulation in leaves that can decrease photosynthetic performance and crop yield. Materials that scavenge ROS and simultaneously provide nutrients in vivo are needed to manage this stress. Here, we incorporated both ROS scavenging and ROS triggered agent release functionality into an ∼20 nm ROS responsive star polymer (RSP) poly(acrylic acid)-block-poly((2-(methylsulfinyl)ethyl acrylate)-co-(2-(methylthio)ethyl acrylate)) (PAA-b-P(MSEA-co-MTEA)) that alleviated plant stress by simultaneous ROS scavenging and nutrient agent release. Hyperspectral imaging indicates that all of the RSP penetrates through the tomato leaf epidermis, and 32.7% of the applied RSP associates with chloroplasts in mesophyll. RSP scavenged up to 10 µmol mg-1 ROS in vitro and suppressed ROS in vivo in stressed tomato (Solanum lycopersicum) leaves. Reaction of the RSP with H2O2in vitro enhanced the release of nutrient agent (Mg2+) from star polymers. Foliar applied RSP increased photosynthesis in plants under heat and light stress compared to untreated controls, enhancing the carbon assimilation, quantum yield of CO2 assimilation, Rubisco carboxylation rate, and photosystem II quantum yield. Mg loaded RSP improved photosynthesis in Mg deficient plants, mainly by promoting Rubisco activity. These results indicate the potential of ROS scavenging nanocarriers like RSP to alleviate abiotic stress in crop plants, allowing crop plants to be more resilient to heat stress, and potentially other climate change induced abiotic stressors.


Assuntos
Polímeros , Solanum lycopersicum , Peróxido de Hidrogênio , Fotossíntese , Folhas de Planta , Espécies Reativas de Oxigênio , Ribulose-Bifosfato Carboxilase
13.
Macromol Biosci ; 21(5): e2000413, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33713560

RESUMO

Charged phospholipids are employed to formulate liposomes with different surface charges to enhance the permeation of active ingredients through epidermal layers. Although 3D skin tissue is widely employed as an alternative to permeation studies using animal skin, only a small number of studies have compared the difference between these skin models. Liposomal delivery strategies are investigated herein, through 3D skin tissue based on their surface charges. Cationic, anionic, and neutral liposomes are formulated and their size, zeta-potential, and morphology are characterized using dynamic light scattering and cryogenic-transmission electron microscopy (cryo-TEM). A Franz diffusion cell is employed to determine the delivery efficiency of various liposomes, where all liposomes do not exhibit any recognizable difference of permeation through the synthetic membrane. When the fluorescence liposomes are applied to 3D skin, considerable fluorescence intensity is observed at the stratum cornea and epithelium layers. Compared to other liposomes, cationic liposomes exhibit the highest fluorescence intensity, suggesting the enhanced permeation of liposomes through the 3D skin layers. Finally, the ability of niacinamide (NA)-incorporated liposomes to suppress melanin transfer in pigmented 3D skin is examined, where cationic liposomes exhibit the highest degree of whitening effects.


Assuntos
Lipossomos , Modelos Biológicos , Absorção Cutânea , Preparações Clareadoras de Pele/farmacocinética , Pigmentação da Pele , Pele/metabolismo , Cátions , Microscopia Crioeletrônica/métodos , Portadores de Fármacos , Células HEK293 , Humanos , Microscopia Eletrônica de Transmissão/métodos
14.
Int J Pharm ; 579: 119162, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32081793

RESUMO

Herein, we report on a ceramide-coassembled lipid nanovehicle (CLNV) system that can enhance the penetration of active ingredients through the skin barrier by taking advantage of molecular associations between ceramide and lipids in the stratum corneum (SC) layer. For this purpose, we fabricated CLNVs consisting of an asymmetric lipid and a cholesterol derivative. They showed excellent long-term dispersion stability without molecular crystallization of ceramide. Upon forming a stable aqueous dispersion, the CLNVs retained their initial vehicle structure even under harsh conditions including high storage temperatures or salinity conditions. From in vitro skin barrier recovery tests, we observed that topical treatment with CLNVs induced the SC to restore its lamellar structure to the same condition as that prior to chemical damage. An in vivo skin penetration study additionally confirmed that skin penetration was enhanced, since the CLNVs were able to effectively interact with the SC layer. From these results, the CLNVs with robust molecular layer endow various applications in wide range applications including transdermal pharmaceutics delivery systems and cosmetics field.


Assuntos
Ceramidas/química , Lipídeos/química , Nanopartículas/química , Polietilenoglicóis/química , Absorção Cutânea/efeitos dos fármacos , Administração Tópica , Portadores de Fármacos , Estabilidade de Medicamentos , Humanos
15.
J Zhejiang Univ Sci B ; 8(5): 296-301, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17542055

RESUMO

OBJECTIVE: To discuss possible relationships between class III malocclusion and perioral forces by measuring the pressure from the lips and the tongue of children with class III malocclusion. METHODS: Thirty-one children with class III malocclusion were investigated and their perioral forces were measured at rest and during swallowing under natural head position by a custom-made miniperioral force computer measuring system. RESULTS: The resting pressures exerted on the labial side and palatine side of the upper left incisor, as well as the labial side and lingual side of the lower left incisor, were 0 g/cm(2), 0 g/cm(2), 0.57 g/cm(2) and 0.23 g/cm(2), respectively. Correspondingly, the swallowing forces were 2.87 g/cm(2), 5.97 g/cm(2), 4.09 g/cm(2) and 7.89 g/cm(2), respectively. No statistical difference between muscular pressure and gender existed. During swallowing, the lingual forces were significantly higher than the labial forces (P<0.01), however, at rest there was no significantly different force between these two sides. Compared to the normal occlusion patients, children with class III malocclusion had lower perioral forces. The upper labial resting forces (P<0.01), the lower labial resting forces (P<0.05) and all the swallowing pressures from the lips and the tongue (P<0.01) showed statistical differences between the two different occlusion conditions. Meanwhile, no significant difference was found for the resting pressure from the tongue between class III malocclusion and normal occlusion. CONCLUSION: Patients with class III malocclusion have lower perioral forces and this muscle hypofunction may be secondary to the spatial relations of the jaws. The findings support the spatial matrix hypothesis.


Assuntos
Força de Mordida , Análise do Estresse Dentário/métodos , Lábio/fisiopatologia , Má Oclusão Classe III de Angle/fisiopatologia , Contração Muscular , Músculo Esquelético/fisiopatologia , Língua/fisiopatologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pressão
16.
J Tissue Eng Regen Med ; 11(1): 99-108, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-24888975

RESUMO

The retinal pigment epithelium (RPE) plays a critical role in the maintenance of the normal functions of the retina, particularly the photoreceptors. RPE dysfunction, vision loss and degeneration have been implicated as the cause of many retinal diseases, including retinitis pigmentosa and age-related macular degeneration (AMD). To overcome such disorders, tissue engineering could offer useful strategies, using biodegradable polymeric films to replace diseased or lost RPE. Synthetic/natural hybrid films have been studied as a temporary substrate for growing RPEs in biological implantations. In this study, we prepared small intestinal submucosa (SIS)-poly(lactic-co-glycolic) (PLGA) hybrid films and seeded human RPE cells (ARPE-19 cells) onto the film surface. We investigated the film suitability for RPE cell proliferation by MTT assay. The morphology of cellular adhesion on the film was confirmed by scanning electron microscopy (SEM). Reverse transcription-polymerase chain reaction (RT-PCR) and 3-amino-9-ethylcarbazole (AEC) staining were performed to examine mRNA expression and to compare cell proliferation on the films, using cytokeratin as a marker of RPE. Conclusively, we confirmed the higher cell survival rate and much stronger phenotype expression of RPEs on SIS-PLGA films compared to pure PLGA films. These results demonstrated the potential application of SIS-PLGA films in tissue-engineering strategies. Copyright © 2014 John Wiley & Sons, Ltd.


Assuntos
Técnicas de Cultura de Células/métodos , Mucosa Intestinal/citologia , Intestino Delgado/citologia , Medicina Regenerativa/instrumentação , Epitélio Pigmentado da Retina/citologia , Engenharia Tecidual/instrumentação , Materiais Biocompatíveis , Adesão Celular , Linhagem Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Humanos , Ácido Láctico/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Medicina Regenerativa/métodos , Resistência à Tração , Engenharia Tecidual/métodos
17.
Angle Orthod ; 75(5): 785-90, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16279824

RESUMO

This study evaluated the distributing characteristic of the forces exerting on the normal deciduous dentition and the relationship between the muscular forces, sex, and oral function. The pressure measurements were made with a computer-aided perioral force-measuring system designed by the authors. The forces were measured when the subject's head position was in a state of natural head position and oral function was at rest or with swallowing. The results indicated that the forces from lips, cheeks, and tongue at rest were about 37-208 N/m2, whereas the pressure during swallowing was about 1009-1679 N/m2. At rest, the pressure from lips and cheeks was higher than that from tongue (P < .05), whereas during swallowing, the lingual pressure was statistically larger (P < .001). A significant correlation existed between the muscular pressure and sex. When at rest, the boy's force from cheeks was higher than that of the girl's (P < .05) but during swallowing the boy's labial pressure was statistically higher than that of the girl's (P < .01). It was concluded that (1) the deciduous teeth are not in a state of absolute balance between external and internal forces, (2) the distributing manner and unbalanced mode of the forces are different with the different oral functions, (3) the lingual side of the mandibular anterior teeth endures great differences during oral functions and it may account for high incidence of malocclusion in this segment, and (4) a statistical difference between muscular forces and sex exists.


Assuntos
Análise do Estresse Dentário , Músculos Faciais/fisiologia , Dente Decíduo/fisiologia , Bochecha/fisiologia , Criança , Pré-Escolar , Deglutição/fisiologia , Análise do Estresse Dentário/instrumentação , Feminino , Humanos , Lábio/fisiologia , Masculino , Fatores Sexuais , Processamento de Sinais Assistido por Computador , Estatísticas não Paramétricas , Língua/fisiologia , Transdutores de Pressão
18.
J Biomater Sci Polym Ed ; 26(2): 92-110, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25431827

RESUMO

The aim of this study was to investigate the effect of demineralized bone particle/ poly(lactic-co-glycolic acid) (DBP/PLGA) scaffolds on the proliferation of mesenchymal stem cells (MSCs). DBP/PLGA hybrid scaffolds were fabricated by solvent casting/salt-leaching with DBP contents of 0, 20, 40, and 80 wt%. MSCs were seeded on the DBP/PLGA scaffolds and then evaluated by a series of analytical process: SEM, MTT, RT-PCR, and in vivo histological assay. As the DBP contents increased, the cell attachment behavior and cell viability also increased. A DBP content of 80 wt% marked the best water absorption performance and the highest cell viability. Gene expression of aggrecan on DBP/PLGA scaffolds tended to increase, whereas that on PLGA scaffolds was decreased at 1 week. However, strong expression of aggrecan was observed at 2 weeks regardless of the contents of DBP. Scaffolds showed a trend of increasing type II and I collagen at 2 weeks. The results showed that MSCs on DBP/PLGA scaffolds showed more efficient cell proliferation and tissue formation in the presence of tissue-inductive stimuli. Suitable biomaterials could be more conducive to proliferation of MSCs. These results suggest that the DBP/PLGA scaffolds are a feasible biomaterial for intervertebral disc regeneration.


Assuntos
Adesão Celular , Proliferação de Células , Ácido Láctico/química , Células-Tronco Mesenquimais/fisiologia , Ácido Poliglicólico/química , Alicerces Teciduais , Agrecanas/metabolismo , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Técnica de Desmineralização Óssea , Bovinos , Sobrevivência Celular , Células Cultivadas , Colágeno Tipo I/metabolismo , Colágeno Tipo II/metabolismo , Feminino , Expressão Gênica , Humanos , Ácido Láctico/síntese química , Teste de Materiais , Células-Tronco Mesenquimais/ultraestrutura , Ácido Poliglicólico/síntese química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos Wistar , Água/química
19.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 33(4): 344-8, 2004 07.
Artigo em Zh | MEDLINE | ID: mdl-15269988

RESUMO

OBJECTIVE: To measure the muscle pressure exerted on the deciduous normal occlusion and to explore the relationship between the denture,occlusion, skeleton and muscle pressure. METHODS: Thirty volunteers of deciduous normal occlusion were included in the study. The muscle pressure of natural head posture (NHP) was measured at rest and during swallowing by a PC real-time measuring system and the data were analyzed by statistical software SAS. RESULT: The forces from lips, cheeks and tongue at rest were 0 approximate, equals 1.47 g/cm(2), while the pressure were increased to 9.60 approximate, equals 20.13 g/cm(2) during swallowing. The lip pressure was higher than the lingual side but there was no statistical difference at rest. The boys had higher pressure than girls,but there was also no statistical difference at rest. The pressure of normal occlusion was related to sex at the position of the upper labial incisor and the side of the dental arch during swallowing. The pressure of both sides of the dental arch increased significantly during swallowing. CONCLUSION: The deciduous dentition is in a state of dynamic equilibrium. This equilibrium may result in a special facial morphology.


Assuntos
Oclusão Dentária , Músculos/fisiologia , Dente Decíduo , Criança , Pré-Escolar , Deglutição , Feminino , Humanos , Masculino , Postura , Pressão , Fatores Sexuais
20.
J Colloid Interface Sci ; 394: 44-8, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23348001

RESUMO

Quantum dot (QD)-assembled silica nanoparticles bearing a polydiacetylene (PDA) supramolecule on their surface (SiO(2)@QDs@PDA NPs) were developed for label-free and multiplexed detection of biological molecules. Two types of QD-assembled silica NPs (SiO(2)@QDs NPs) were prepared and coated with the PDA supramolecule via photo-induced polymerization of 10,12-pentacosadiynoic acid. One of the SiO(2)@QDs NPs was embedded with blue-QDs, and the other was embedded with green-QDs for encoding. The resulting SiO(2)@QDs@PDA NPs showed discrete QD photoluminescence for encoding as well as PDA fluorescence for sensing a target without interference or overlap. Under heating stress of the SiO(2)@QDs@PDA NPs, the color of the PDA changed from blue to red, which allowed us to observe the fluorescence emitted from red PDA. The mixture of two different SiO(2)@QDs@PDA NPs, SiO(2)@QDs@blue-PDA NPs not emitting the fluorescence of PDA and SiO(2)@QDs@red-PDA NPs where stress was brought onto turn on the PDA fluorescence, was effectively imaged and readily distinguished via fluorescence microscopy, indicating their potential for label-free and multiplexed detection of target molecules.


Assuntos
Corantes Fluorescentes/química , Nanopartículas/química , Polímeros/química , Poli-Inos/química , Pontos Quânticos , Dióxido de Silício/química , Microscopia de Fluorescência , Nanopartículas/ultraestrutura , Polímero Poliacetilênico
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