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1.
Int J Mol Sci ; 22(7)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33916310

RESUMO

Epidemiological evidence shows that smoking causes a thrombophilic milieu that may play a role in the pathophysiology of chronic obstructive pulmonary disease (COPD) as well as pulmonary thromboembolism. The increased nicotine level induces a prothrombotic status and abnormal blood coagulation in smokers. Since several anticoagulants increase bleeding risk, alternative therapies need to be identified to protect against thrombosis without affecting hemostasis. Astragalin is a flavonoid present in persimmon leaves and green tea seeds and exhibits diverse activities of antioxidant and anti-inflammation. The current study investigated that astragalin attenuated smoking-induced pulmonary thrombosis and alveolar inflammation. In addition, it was explored that molecular links between thrombosis and inflammation entailed protease-activated receptor (PAR) activation and oxidative stress-responsive mitogen-activated protein kinase (MAPK)-signaling. BALB/c mice were orally administrated with 10-20 mg/kg astragalin and exposed to cigarette smoke for 8 weeks. For the in vitro study, 10 U/mL thrombin was added to alveolar epithelial A549 cells in the presence of 1-20 µM astragalin. The cigarette smoking-induced the expression of PAR-1 and PAR-2 in lung tissues, which was attenuated by the administration of ≥10 mg/kg astragalin. The oral supplementation of ≥10 mg/kg astragalin to cigarette smoke-challenged mice attenuated the protein induction of urokinase plasminogen activator, plasminogen activator inhibitor-1and tissue factor, and instead enhanced the induction of tissue plasminogen activator in lung tissues. The astragalin treatment alleviated cigarette smoke-induced lung emphysema and pulmonary thrombosis. Astragalin caused lymphocytosis and neutrophilia in bronchoalveolar lavage fluid due to cigarette smoke but curtailed infiltration of neutrophils and macrophages in airways. Furthermore, this compound retarded thrombin-induced activation of PAR proteins and expression of inflammatory mediators in alveolar cells. Treating astragalin interrupted PAR proteins-activated reactive oxygen species production and MAPK signaling leading to alveolar inflammation. Accordingly, astragalin may interrupt the smoking-induced oxidative stress-MAPK signaling-inflammation axis via disconnection between alveolar PAR activation and pulmonary thromboembolism.


Assuntos
Quempferóis/uso terapêutico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Embolia Pulmonar/prevenção & controle , Enfisema Pulmonar/prevenção & controle , Receptores Ativados por Proteinase/antagonistas & inibidores , Animais , Fumar Cigarros/efeitos adversos , Avaliação Pré-Clínica de Medicamentos , Quempferóis/farmacologia , Masculino , Camundongos Endogâmicos BALB C , Estresse Oxidativo , Embolia Pulmonar/etiologia
2.
Radiology ; 297(3): 640-649, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32990513

RESUMO

Background Large vessel occlusion (LVO) stroke is one of the most time-sensitive diagnoses in medicine and requires emergent endovascular therapy to reduce morbidity and mortality. Leveraging recent advances in deep learning may facilitate rapid detection and reduce time to treatment. Purpose To develop a convolutional neural network to detect LVOs at multiphase CT angiography. Materials and Methods This multicenter retrospective study evaluated 540 adults with CT angiography examinations for suspected acute ischemic stroke from February 2017 to June 2018. Examinations positive for LVO (n = 270) were confirmed by catheter angiography and LVO-negative examinations (n = 270) were confirmed through review of clinical and radiology reports. Preprocessing of the CT angiography examinations included vasculature segmentation and the creation of maximum intensity projection images to emphasize the contrast agent-enhanced vasculature. Seven experiments were performed by using combinations of the three phases (arterial, phase 1; peak venous, phase 2; and late venous, phase 3) of the CT angiography. Model performance was evaluated on the held-out test set. Metrics included area under the receiver operating characteristic curve (AUC), sensitivity, and specificity. Results The test set included 62 patients (mean age, 69.5 years; 48% women). Single-phase CT angiography achieved an AUC of 0.74 (95% confidence interval [CI]: 0.63, 0.85) with sensitivity of 77% (24 of 31; 95% CI: 59%, 89%) and specificity of 71% (22 of 31; 95% CI: 53%, 84%). Phases 1, 2, and 3 together achieved an AUC of 0.89 (95% CI: 0.81, 0.96), sensitivity of 100% (31 of 31; 95% CI: 99%, 100%), and specificity of 77% (24 of 31; 95% CI: 59%, 89%), a statistically significant improvement relative to single-phase CT angiography (P = .01). Likewise, phases 1 and 3 and phases 2 and 3 also demonstrated improved fit relative to single phase (P = .03). Conclusion This deep learning model was able to detect the presence of large vessel occlusion and its diagnostic performance was enhanced by using delayed phases at multiphase CT angiography examinations. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Ospel and Goyal in this issue.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Redes Neurais de Computação , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Angiografia Cerebral , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
3.
Int J Mol Sci ; 21(15)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32752252

RESUMO

Pulmonary fibrosis is a disease in which lung tissues become fibrous and thereby causes severe respiratory disturbances. Various stimuli induce infiltration of macrophages to the respiratory tract, secreting inflammatory cytokines, which subsequently leads to the development of pulmonary fibrosis. Aesculetin, a major component of the sancho tree and chicory, is known to biologically have antioxidant and anti-inflammatory effects. Human alveolar epithelial A549 cells were cultured for 24 h in conditioned media of THP-1 monocyte-derived macrophages (mCM) with 1-20 µM aesculetin. Micromolar aesculetin attenuated the cytotoxicity of mCM containing inflammatory tumor necrosis factor-α (TNF)-α and interleukin (IL)-8 as major cytokines. Aesculetin inhibited alveolar epithelial induction of the mesenchymal markers in mCM-exposed/IL-8-loaded A549 cells (≈47-51% inhibition), while epithelial markers were induced in aesculetin-treated cells subject to mCM/IL-8 (≈1.5-2.3-fold induction). Aesculetin added to mCM-stimulated A549 cells abrogated the collagen production and alveolar epithelial CXC-chemokine receptor 2 (CXCR2) induction. The production of matrix metalloproteinase (MMP) proteins in mCM-loaded A549 cells was reduced by aesculetin (≈52% reduction), in parallel with its increase in tissue inhibitor of metalloproteinases (TIMP) proteins (≈1.8-fold increase). In addition, aesculetin enhanced epithelial induction of tight junction proteins in mCM-/IL-8-exposed cells (≈2.3-2.5-fold induction). The inhalation of polyhexamethylene guanidine (PHMG) in mice accompanied neutrophil predominance in bronchoalveolar lavage fluid (BALF) and macrophage infiltration in alveoli, which was inhibited by orally administrating aesculetin to mice. Treating aesculetin to mice alleviated PHMG-induced IL-8-mediated subepithelial fibrosis and airway barrier disruption. Taken together, aesculetin may antagonize pulmonary fibrosis and alveolar epithelial barrier disruption stimulated by the infiltration of monocyte-derived macrophages, which is typical of PHMG toxicity, involving interaction of IL-8 and CXCR2. Aesculetin maybe a promising agent counteracting macrophage-mediated inflammation-associated pulmonary disorders.


Assuntos
Células Epiteliais Alveolares/efeitos dos fármacos , Interleucina-8/metabolismo , Macrófagos/metabolismo , Alvéolos Pulmonares/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Umbeliferonas/farmacologia , Células A549 , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Animais , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fibrose , Humanos , Masculino , Camundongos Endogâmicos BALB C , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Fibrose Pulmonar/prevenção & controle , Células THP-1
4.
Int J Mol Sci ; 21(22)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33203061

RESUMO

For the optimal resorption of mineralized bone matrix, osteoclasts require the generation of the ruffled border and acidic resorption lacuna through lysosomal trafficking and exocytosis. Coumarin-type aesculetin is a naturally occurring compound with anti-inflammatory and antibacterial effects. However, the direct effects of aesculetin on osteoclastogenesis remain to be elucidated. This study found that aesculetin inhibited osteoclast activation and bone resorption through blocking formation and exocytosis of lysosomes. Raw 264.7 cells were differentiated in the presence of 50 ng/mL receptor activator of nuclear factor-κB ligand (RANKL) and treated with 1-10 µM aesculetin. Differentiation, bone resorption, and lysosome biogenesis of osteoclasts were determined by tartrate-resistance acid phosphatase (TRAP) staining, bone resorption assay, Western blotting, immunocytochemical analysis, and LysoTracker staining. Aesculetin inhibited RANKL-induced formation of multinucleated osteoclasts with a reduction of TRAP activity. Micromolar aesculetin deterred the actin ring formation through inhibition of induction of αvß3 integrin and Cdc42 but not cluster of differentiation 44 (CD44) in RANKL-exposed osteoclasts. Administering aesculetin to RANKL-exposed osteoclasts attenuated the induction of autophagy-related proteins, microtubule-associated protein light chain 3, and small GTPase Rab7, hampering the lysosomal trafficking onto ruffled border crucial for bone resorption. In addition, aesculetin curtailed cellular induction of Pleckstrin homology domain-containing protein family member 1 and lissencephaly-1 involved in lysosome positioning to microtubules involved in the lysosomal transport within mature osteoclasts. These results demonstrate that aesculetin retarded osteoclast differentiation and impaired lysosomal trafficking and exocytosis for the formation of the putative ruffled border. Therefore, aesculetin may be a potential osteoprotective agent targeting RANKL-induced osteoclastic born resorption for medicinal use.


Assuntos
Reabsorção Óssea/metabolismo , Lisossomos/metabolismo , Osteoclastos/metabolismo , Umbeliferonas/farmacologia , Animais , Antígenos de Diferenciação/metabolismo , Transporte Biológico Ativo/efeitos dos fármacos , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/patologia , Lisossomos/patologia , Camundongos , Osteoclastos/patologia , Células RAW 264.7
5.
Arch Biochem Biophys ; 653: 97-106, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30018019

RESUMO

Glu-267 is highly conserved in alcohol dehydrogenases and buried as a negatively-charged residue in a loop of the NAD coenzyme binding domain. Glu-267 might have a structural role and contribute to a rate-promoting vibration that facilitates catalysis. Substitutions of Glu-267 with histidine or asparagine residues increase the dissociation constants for the coenzymes (NAD+ by ∼40-fold, NADH by ∼200-fold) and significantly decrease catalytic efficiencies by 16-1200-fold various substrates and substituted enzymes. The turnover numbers modestly change with the substitutions, but hydride transfer is at least partially rate-limiting for turnover for alcohol oxidation. X-ray structures of the E267H and E267 N enzymes are similar to the apoenzyme (open) conformation of the wild-type enzyme, and the substitutions are accommodated by local changes in the structure. Surprisingly, the E267H and E267 N enzymes have endogenous (from the expression in E. coli) 3'-dephosphocoenzyme A bound in the active site with the ADP moiety in the NAD binding site and the pantethiene sulfhydryl bound to the catalytic zinc. The kinetics and crystallography show that the substitutions of Glu-267 hinder the conformational change, which occurs when wild-type enzyme binds coenzymes, and affect productive binding of substrates.


Assuntos
Álcool Desidrogenase/metabolismo , Coenzima A/metabolismo , Ácido Glutâmico/metabolismo , Fígado/enzimologia , Álcool Desidrogenase/química , Álcool Desidrogenase/genética , Animais , Catálise , Cristalografia por Raios X , Cavalos , Cinética , Ligantes , Mutagênese Sítio-Dirigida , Conformação Proteica , Especificidade por Substrato
6.
Phys Chem Chem Phys ; 19(23): 15521-15529, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28581548

RESUMO

We developed a facile method for treating polyimide-based organic gate insulator (OGI) surfaces with self-assembled monolayers (SAMs) by introducing metal-oxide interlayers, called the metal-oxide assisted SAM treatment (MAST). To create sites for surface modification with SAM materials on polyimide-based OGI (KPI) surfaces, the metal-oxide interlayer, here amorphous alumina (α-Al2O3), was deposited on the KPI gate insulator using spin-coating via a rapid sol-gel reaction, providing an excellent template for the formation of a high-quality SAM with phosphonic acid anchor groups. The SAM of octadecylphosphonic acid (ODPA) was successfully treated by spin-coating onto the α-Al2O3-deposited KPI film. After the surface treatment by ODPA/α-Al2O3, the surface energy of the KPI thin film was remarkably decreased and the molecular compatibility of the film with an organic semiconductor (OSC), 2-decyl-7-phenyl-[1]benzothieno[3,2-b][1]benzothiophene (Ph-BTBT-C10), was increased. Ph-BTBT-C10 molecules were uniformly deposited on the treated gate insulator surface and grown with high crystallinity, as confirmed by atomic force microscopy (AFM) and X-ray diffraction (XRD) analysis. The mobility of Ph-BTBT-C10 thin-film transistors (TFTs) was approximately doubled, from 0.56 ± 0.05 cm2 V-1 s-1 to 1.26 ± 0.06 cm2 V-1 s-1, after the surface treatment. The surface treatment of α-Al2O3 and ODPA significantly decreased the threshold voltage from -21.2 V to -8.3 V by reducing the trap sites in the OGI and improving the interfacial properties with the OSC. We suggest that the MAST method for OGIs can be applied to various OGI materials lacking reactive sites using SAMs. It may provide a new platform for the surface treatment of OGIs, similar to that of conventional SiO2 gate insulators.

7.
Acta Pharmacol Sin ; 38(8): 1129-1140, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28502979

RESUMO

Glomerular epithelial podocytes are highly specialized cells that play a crucial role in maintaining normal function of the glomerular filtration barrier via their foot processes. Chrysin (5,7-dihydroxyflavone) is a natural flavonoid found in propolis and mushrooms that has anti-inflammatory, antioxidant and anticancer properties. This study aimed to evaluate the renoprotective effects of chrysin on podocyte apoptotic loss and slit diaphragm protein deficiency in high glucose-exposed podocytes and in db/db mouse kidneys. Exposure to high glucose (33 mmol/L) caused glomerular podocyte apoptosis in vitro, which was dose-dependently attenuated by nontoxic chrysin (1-20 µmol/L) through reduction of DNA fragmentation. Chrysin treatment dose-dependently restored the increased Bax/Bcl-2 ratio, and suppressed Apaf-1 induction and the elevated cytochrome c release in high glucose-exposed renal podocytes. In diabetic db/db mice, oral administration of chrysin (10 mg·kg-1·d-1, for 10 weeks) significantly attenuated proteinuria, and alleviated the abnormal alterations in glomerular ultrastructure, characterized by apoptotic podocytes and foot process effacement. In addition, this compound improved the induction of slit diaphragm proteins podocin/nephrin in the diabetic glomeruli. Exposure to high glucose elevated the unfolded protein response (UPR) to ER stress in renal podocytes, evidenced by up-regulation of PERK-eIF2α-ATF4-CHOP. Chrysin treatment blocked such ER stress responses pertinent to podocyte apoptosis and reduced synthesis of slit diaphragm proteins in vitro and in vivo. These observations demonstrate that targeting ER stress is an underlying mechanism of chrysin-mediated amelioration of diabetes-associated podocyte injury and dysfunction.


Assuntos
Nefropatias Diabéticas/prevenção & controle , Flavonoides/farmacologia , Podócitos/efeitos dos fármacos , Proteinúria/prevenção & controle , Transdução de Sinais/efeitos dos fármacos , Fator 4 Ativador da Transcrição/metabolismo , Animais , Apoptose/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Relação Dose-Resposta a Droga , Glucose/farmacologia , Masculino , Camundongos , Fator de Transcrição CHOP/metabolismo , eIF-2 Quinase/metabolismo
8.
Nano Lett ; 16(7): 3969-75, 2016 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-27223230

RESUMO

The moderate band gap of black phosphorus (BP) in the range of 0.3-2 eV, along a high mobility of a few hundred cm(2) V(-1) s(-1) provides a bridge between the gapless graphene and relatively low-mobility transition metal dichalcogenides. Here, we study the mechanism of electrical and thermoelectric transport in 10-30 nm thick BP devices by measurements of electrical conductance and thermopower (S) with various temperatures (T) and gate-electric fields. The T dependences of S and the sheet conductance (σ□) of the BP devices show behaviors of T(1/3) and exp[-(1/T)(1/3)], respectively, where S reaches ∼0.4 mV/K near room T. This result indicates that two-dimensional (2D) Mott's variable range hopping (VRH) is a dominant mechanism in the thermoelectric and electrical transport in our examined thin BP devices. We consider the origin of the 2D Mott's VRH transport in our BPs as trapped charges at the surface of the underlying SiO2 based on the analysis with observed multiple quantum dots.

9.
Langmuir ; 32(50): 13418-13426, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27993016

RESUMO

Controlling the organization of self-assembling building blocks over a large area is crucial for lithographic tools based on the bottom-up approach. However, the fabrication of liquid crystal (LC) defect patterns with a particular ordering still remains a challenge because of the limited close-packed morphologies of LC defects. Here, we introduce a multiple-stamping domain separation method for the control of the dimensions and organization of LC defect structures. Prepatterns with various grid shapes on planar polyimide (PI) surfaces were fabricated by pressing a line-shaped stamp into the PI surfaces in two different directions, and then these surfaces were used to prepare LC defect structures confined to these grid domains. The dimensions of the LC defect structures, namely, the equilibrium diameter and the center to center spacing, are controlled by varying the line spacing of the stamps and the film thickness. A variety of arrangements of LC defects, including square, rhombic, hexagonal, and other oblique lattices, can be obtained by simply varying the stamping angle (Ω) between the first and second stamping directions. Furthermore, we demonstrate that the resulting controllable LC defect arrays can be used as templates for generating various patterns of nanoparticle clusters by trapping quantum dots (QDs) within the cores of the LC defects.

10.
Phys Chem Chem Phys ; 18(12): 8522-8, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-26940136

RESUMO

This study investigates a spin-coating method for modifying the surface properties of a poly(ethylene-alt-maleic anhydride) (PEMA) gate insulator. The 60 nm-thick PEMA thin film exhibits excellent electrical insulating properties, and its surface properties could be easily modified by surface grafting of octylamine. Due to surface treatment via spin-coating, the surface energy of the PEMA gate insulator decreased, the crystal quality of the organic semiconductor improved, and consequently the performance of low-voltage organic thin-film transistors (TFTs) was enhanced. Our results suggest that the surface treatment of the PEMA gate insulator could be a simple and effective method for enhancing the performance of organic TFTs.

11.
Proc Natl Acad Sci U S A ; 110(48): 19263-7, 2013 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-24218602

RESUMO

Layering is found and exploited in a variety of soft material systems, ranging from complex macromolecular self-assemblies to block copolymer and small-molecule liquid crystals. Because the control of layer structure is required for applications and characterization, and because defects reveal key features of the symmetries of layered phases, a variety of techniques have been developed for the study of soft-layer structure and defects, including X-ray diffraction and visualization using optical transmission and fluorescence confocal polarizing microscopy, atomic force microscopy, and SEM and transmission electron microscopy, including freeze-fracture transmission electron microscopy. Here, it is shown that thermal sublimation can be usefully combined with such techniques to enable visualization of the 3D structure of soft materials. Sequential sublimation removes material in a stepwise fashion, leaving a remnant layer structure largely unchanged and viewable using SEM, as demonstrated here using a lamellar smectic liquid crystal.


Assuntos
Imageamento Tridimensional/métodos , Teste de Materiais/métodos , Nanoestruturas/ultraestrutura , Propriedades de Superfície , Cristais Líquidos/química , Microscopia de Força Atômica , Microscopia Eletrônica , Microscopia de Fluorescência , Termogravimetria , Difração de Raios X
12.
J Orthop Sci ; 21(3): 299-305, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26992270

RESUMO

BACKGROUND: Pain catastrophizing is a key variable that contributes to disability not only in chronic pain disorders but also after trauma. However, there is little evidence concerning the effect of catastrophizing on pain intensity and disability after osteoporotic vertebral compression fracture. Therefore, the purpose of this study was to evaluate the contribution of catastrophizing to disability and pain intensity after osteoporotic vertebral compression fracture. METHOD: We analyzed 35 patients with acute single-level osteoporotic vertebral compression fractures within 3 days of trauma. Data on demographics, education level, Charlson comorbidity index, pain catastrophizing scale (PCS) score, visual analog scale (VAS) score for back pain, and Oswestry Disability Index (ODI) were collected. VAS score for back pain and ODI were assessed at enrollment as well as at 2, 6, and 12 weeks after fracture. RESULTS: Each VAS score for back pain and ODI significantly improved compared to the initial values (P < 0.001). Among the independent variables, age and/or PCS score significantly correlated with VAS score for back pain and/or ODI over follow-up assessments. Hierarchical regression analysis finally showed that PCS score was a significant predictor for disability only in the acute period such as immediately and 2 weeks after fracture, whereas age was significantly associated with ODI at 6 and 12 weeks after fracture. CONCLUSIONS: The present study shows that catastrophizing can contribute to disability only in the acute period after osteoporotic vertebral compression fracture. As the compression fracture heals, however, age is the critical determinant of disability.


Assuntos
Avaliação da Deficiência , Fraturas por Compressão/psicologia , Fraturas por Osteoporose/prevenção & controle , Medição da Dor/métodos , Fraturas da Coluna Vertebral/psicologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Braquetes , Estudos de Coortes , Escolaridade , Feminino , Fraturas por Compressão/diagnóstico por imagem , Fraturas por Compressão/terapia , Humanos , Japão , Modelos Lineares , Masculino , Análise Multivariada , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/terapia , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores Sexuais , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/terapia
13.
Nano Lett ; 15(11): 7552-7, 2015 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-26437237

RESUMO

Developing large-area, single domain of organic soft-building blocks such as block copolymers, colloids, and supramolecular materials is one of the most important issues in the materials science and nanotechnology. Owing to their small sizes, complex molecular architectures, and high mobility, supramolecular materials are not well-suited for building large area, single domain structures. In the described study, a single domain of supramolecular columnar dendrimers was created over large area. The columnar structures in these domains have smaller (4.5 nm) diameters, higher area densities (ca. 36 Tera-dots/in(2)) and larger domains (>0.1 × 0.1 mm(2)) than those of all existing BCP and colloidal assemblies. By simply annealing dendrimer thin films between two flat solid surfaces, single domains of hexagonal columnar structures are created over large macroscopic areas. Observations made in this effort should serve as the foundation for the design of new routes for bottom-up lithography based on supramolecular building blocks.

14.
Nano Lett ; 15(1): 229-34, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25494827

RESUMO

Because the properties of molybdenum disulfide (MoS2) are strongly influenced by the sizes and boundaries of its domains, the direct visualization of large-area MoS2 domains is one of the most important challenges in MoS2 research. In the current study, we developed a simple and rapid method to observe and determine the boundaries of MoS2 domains. The technique, which depends on observations of nematic liquid crystal textures on the MoS2 surface, does not damage the sample and is not limited by domain size. Thus, this approach should significantly aid not only efforts aimed at gaining an understanding of the relationships between grain boundaries and properties of MoS2 but also those focusing on how domain sizes are controlled during large-area synthesis.

15.
Int Wound J ; 13 Suppl 1: 33-41, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26847937

RESUMO

To investigate whether diabetes mellitus affects the wound-healing-promoting potential of adipose tissue-derived stem cells, we designed a wound-healing model using diabetic mice. We compared the degree of wound healing between wounds treated with normal adipose tissue-derived stem cells and wounds treated with diabetic adipose tissue-derived stem cells. We evaluated the wound-healing rate, the epithelial tongue distance, the area of granulation tissue, the number of capillary and the number of Ki-67-stained cells. The wound-healing rate was significantly higher in the normal adipose tissue-derived stem cells group than in the diabetic adipose tissue-derived stem cells group; it was also significantly higher in the normal adipose tissue-derived stem cells group than in the control group. Although the diabetic adipose tissue-derived stem cells group showed a better wound-healing rate than the control group, the difference was not statistically significant. Similar trends were observed for the other parameters examined: re-epithelisation and keratinocyte proliferation; granulation tissue formation; and dermal regeneration. However, with regard to the number of capillary, diabetic adipose tissue-derived stem cells retained their ability to promote neovasculisation and angiogenesis. These results reflect the general impairment of the therapeutic potential of diabetic adipose tissue-derived stem cells in vivo.


Assuntos
Tecido Adiposo/citologia , Diabetes Mellitus Experimental/fisiopatologia , Células-Tronco/fisiologia , Cicatrização/fisiologia , Animais , Capilares/patologia , Tecido de Granulação/patologia , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Ferimentos e Lesões/patologia
16.
J Craniofac Surg ; 26(3): 849-52, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25901673

RESUMO

We conducted this study to identify preoperative factors that are associated with the postoperative nasal synechiae in patients with nasal bone fracture who underwent closed reduction.In the current single-center, retrospective study, we evaluated the fracture type, septal deviation angle (SDA), synechia scores (SSs) and visual analog scale (VAS) scores through a retrospective review of the medical records and computed tomography scans of 42 patients (n = 42) who had undergone closed reduction for nasal bone fracture at our medical institution during a period ranging from April to August 2013.The mean SS was significantly lower in the plane I group (n = 25) as compared with the plane II group (n = 17) (1.28 ± 1.77 vs 2.76 ± 1.89, P = 0.013). There was a significant positive correlation between the SDA and the SS with a formula of SS = 0.216SDA - 0.322 (r(2) = 0.532, P < 0.001) and between the SS and the VAS with a formula of VAS = 1.280SS + 0.612 (r(2) = 0.648, P < 0.001). Both the SS and VAS were significantly higher on the convex side as compared with the concave side of the nasal cavity.Our results indicate that patients with higher SDA or combined septal fractures might be at increased risks of developing the postoperative synechiae. Further large-scale, prospective studies are warranted to establish our results.


Assuntos
Fixação de Fratura/efeitos adversos , Osso Nasal/lesões , Complicações Pós-Operatórias/diagnóstico , Fraturas Cranianas/diagnóstico , Aderências Teciduais/diagnóstico , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osso Nasal/diagnóstico por imagem , Osso Nasal/cirurgia , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Fraturas Cranianas/cirurgia , Aderências Teciduais/etiologia , Aderências Teciduais/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
17.
Int J Mol Sci ; 16(12): 29980-95, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26694364

RESUMO

Asthma is characterized by aberrant airways including epithelial thickening, goblet cell hyperplasia, and smooth muscle hypertrophy within the airway wall. The current study examined whether kaempferol inhibited mast cell degranulation and prostaglandin (PG) release leading to the development of aberrant airways, using an in vitro model of dinitrophenylated bovine serum albumin (DNP-BSA)-sensitized rat basophilic leukemia (RBL-2H3) mast cells and an in vivo model of BSA-challenged asthmatic mice. Nontoxic kaempferol at 10-20 µM suppressed ß-hexosaminidase release and cyclooxygenase 2 (COX2)-mediated production of prostaglandin D2 (PGD2) and prostaglandin F2α (PGF2α) in sensitized mast cells. Oral administration of ≤20 mg/kg kaempferol blocked bovine serum albumin (BSA) inhalation-induced epithelial cell excrescence and smooth muscle hypertrophy by attenuating the induction of COX2 and the formation of PGD2 and PGF2α, together with reducing the anti-α-smooth muscle actin (α-SMA) expression in mouse airways. Kaempferol deterred the antigen-induced mast cell activation of cytosolic phospholipase A2 (cPLA2) responsive to protein kinase Cµ (PKCµ) and extracellular signal-regulated kinase (ERK). Furthermore, the antigen-challenged activation of Syk-phospholipase Cγ (PLCγ) pathway was dampened in kaempferol-supplemented mast cells. These results demonstrated that kaempferol inhibited airway wall thickening through disturbing Syk-PLCγ signaling and PKCµ-ERK-cPLA2-COX2 signaling in antigen-exposed mast cells. Thus, kaempferol may be a potent anti-allergic compound targeting allergic asthma typical of airway hyperplasia and hypertrophy.


Assuntos
Asma/complicações , Asma/tratamento farmacológico , Dieta , Hipersensibilidade/tratamento farmacológico , Hipersensibilidade/patologia , Quempferóis/uso terapêutico , Pulmão/patologia , Animais , Asma/patologia , Bovinos , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/biossíntese , Modelos Animais de Doenças , Indução Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Hexosaminidases/metabolismo , Hipersensibilidade/complicações , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Quempferóis/química , Quempferóis/farmacologia , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Pulmão/efeitos dos fármacos , Masculino , Camundongos Endogâmicos BALB C , Modelos Biológicos , Fosfolipases A2 , Prostaglandinas/metabolismo , Proteínas Tirosina Quinases/metabolismo , Ratos , Soroalbumina Bovina , Quinase Syk , Fatores de Tempo
18.
Angew Chem Int Ed Engl ; 54(50): 15266-70, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26412162

RESUMO

Cholesteric liquid crystals (CLCs) reflect selected wavelengths of light owing to their periodic helical structures. The encapsulation of CLCs leads to photonic devices that can be easily processed and might be used as stand-alone microsensors. However, when CLCs are enclosed by polymeric membranes, they usually lose their planar alignment, leading to a deterioration of the optical performance. A microfluidics approach was employed to integrate an ultrathin alignment layer into microcapsules to separate the CLC core and the elastomeric solid membrane using triple-emulsion drops as the templates. The thinness of the alignment layer provides high lubrication resistance, preserving the layer integrity during elastic deformation of the membrane. The CLCs in the microcapsules can thus maintain their planar alignment, rendering the shape and optical properties highly reconfigurable.

19.
Opt Express ; 22(25): 30707-12, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25607018

RESUMO

A low-voltage-tunable one-dimensional nanobeam laser is realized by employing lithographically defined lateral electrodes. An InGaAsP nanobeam with a sub-micrometer width is transfer-printed in the middle of two electrodes using a polydimethylsiloxane stamp. Spectral tuning is achieved by controlling the molecular alignment of the surrounding liquid crystals (LCs). From µm-scale-gap structures, a total wavelength shift that exceed 6 nm is observed at a low voltage of less than 10 V. A measured spectral tuning rate of 0.87 nm/V, which is the largest value ever reported to our knowledge among LC-tuned photonic crystal lasers, was also noted.

20.
Opt Express ; 22(4): 4699-704, 2014 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-24663788

RESUMO

We demonstrate large-area, closely-packed optical vortex arrays using self-assembled defects in smectic liquid crystals. Self-assembled smectic liquid crystals in a three-dimensional torus structure are called focal conic domains. Each FCD, having a micro-scale feature size, produces an optical vortex with consistent topological charge of 2. The spiral profile in the interferometry confirms the formation of an optical vortex, which is predicted by Jones matrix calculations.

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