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1.
Int J Oral Maxillofac Surg ; 53(2): 146-155, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37391321

RESUMO

Bilateral maxillary defects are a challenge for fibula free flap reconstruction (FFFR) surgery due to limitations in virtual surgical planning (VSP) workflows. While meshes of unilateral defects can be mirrored to virtually reconstruct missing anatomy, Brown class c and d defects lack a contralateral reference and associated anatomical landmarks. This often results in poor placement of osteotomized fibula segments. This study was performed to improve the VSP workflow for FFFR using statistical shape modeling (SSM) - a form of unsupervised machine learning - to virtually reconstruct premorbid anatomy in an automated, reproducible, and patient-specific manner. A training set of 112 computed tomography scans was sourced from an imaging database by stratified random sampling. The craniofacial skeletons were segmented, aligned, and processed via principal component analysis. Reconstruction performance was validated on a set of 45 unseen skulls containing various digitally generated defects (Brown class IIa-d). Validation metrics demonstrated promising accuracy: mean 95th percentile Hausdorff distance of 5.47 ± 2.39 mm, mean volumetric Dice coefficient of 48.8 ± 14.5%, compactness of 7.28 × 105 mm2, specificity of 1.18 mm, and generality of 8.12 × 10-6 mm. SSM-guided VSP will allow surgeons to create patient-centric treatment plans, increasing FFFR accuracy, reducing complications, and improving postoperative outcomes.


Assuntos
Implantes Dentários , Retalhos de Tecido Biológico , Reconstrução Mandibular , Procedimentos de Cirurgia Plástica , Cirurgia Assistida por Computador , Humanos , Maxila/cirurgia , Crânio/cirurgia , Tomografia Computadorizada por Raios X/métodos , Cirurgia Assistida por Computador/métodos , Reconstrução Mandibular/métodos , Fíbula
2.
Opt Express ; 31(2): 1594-1603, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785191

RESUMO

The NV centers in a diamond were successfully created by the femtosecond laser single pulse. We also investigated the effect on the diamond lattice induced by the different laser pulse widths from both experimental and theoretical perspectives. Interestingly, in spite of the high thermal conductivity of a diamond, we found that there is a suitable pulse repetition rate of several tens kHz for the formation of NV center ensembles by the femtosecond laser pulse irradiation.

3.
Science ; 376(6595): 857-860, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35587979

RESUMO

In plants, many invading microbial pathogens are recognized by cell-surface pattern recognition receptors, which induce defense responses. Here, we show that the ceramide Phytophthora infestans-ceramide D (Pi-Cer D) from the plant pathogenic oomycete P. infestans triggers defense responses in Arabidopsis. Pi-Cer D is cleaved by an Arabidopsis apoplastic ceramidase, NEUTRAL CERAMIDASE 2 (NCER2), and the resulting 9-methyl-branched sphingoid base is recognized by a plasma membrane lectin receptor-like kinase, RESISTANT TO DFPM-INHIBITION OF ABSCISIC ACID SIGNALING 2 (RDA2). 9-Methyl-branched sphingoid base is specific to microbes and induces plant immune responses by physically interacting with RDA2. Loss of RDA2 or NCER2 function compromised Arabidopsis resistance against an oomycete pathogen. Thus, we elucidated the recognition mechanisms of pathogen-derived lipid molecules in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ceramidas , Interações Hospedeiro-Patógeno , Ceramidase Neutra , Phytophthora infestans , Doenças das Plantas , Arabidopsis/genética , Arabidopsis/imunologia , Arabidopsis/microbiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ceramidas/metabolismo , Ceramidase Neutra/genética , Ceramidase Neutra/metabolismo , Phytophthora infestans/patogenicidade , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Receptores Mitogênicos/genética , Receptores Mitogênicos/metabolismo
6.
Environ Sci Process Impacts ; 23(4): 580-587, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33725038

RESUMO

Contamination of drinking water by per- and polyfluoroalkyl substances (PFASs) emitted from manufacturing plants, fire-fighting foams, and urban waste streams has received considerable attention due to concerns over toxicity and environmental persistence; however, PFASs in ambient air remain poorly understood, especially in the United States (US). We measured PFAS concentrations in ambient fine particulate matter (PM2.5) at 5 locations across North Carolina over a 1 year period in 2019. Thirty-four PFASs, including perfluoroalkyl carboxylic, perfluoroalkane sulfonic, perfluoroalkyl ether carboxylic and sulfonic acids were analyzed by UHPLC/ESI-MS/MS. Quarterly averaged concentrations ranged from <0.004-14.1 pg m-3. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) ranged from <0.18 to 14.1 pg m-3, comparable to previous PM2.5 measurements from Canada and Europe (<0.02-3.5 pg m-3). Concentrations above 1 pg m-3 were observed in July-September at Charlotte (14.1 pg m-3, PFOA), Wilmington (4.75 pg m-3, PFOS), and Research Triangle Park (1.37 pg m-3, PFOS). Notably, PM2.5 has a short atmospheric lifetime (<2 weeks), and thus, the presence of PFOS in these samples raises questions about their sources, since PFOS production was phased out in the US ∼20 years ago. This is the first US study to provide insights into ambient PFAS concentrations in PM2.5.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Ácidos Alcanossulfônicos/análise , Canadá , Europa (Continente) , Fluorocarbonos/análise , North Carolina , Material Particulado , Espectrometria de Massas em Tandem
7.
Sci Rep ; 9(1): 1252, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30718745

RESUMO

Root caries is an increasingly problem in aging societies with severe implications for the general health and wellbeing of large numbers of people. Strengthening type-I collagen, a major organic component of human dentin, has proved effective in preventing root caries. This study sought to determine whether exposure to riboflavin followed by UVA irradiation (RF/UVA) could promote additional collagen crosslinking, and thus improve the acid and enzymatic resistance of human dentin under simulated oral environments. If so, it could offer potential for treatment of the intractable problem of root caries. The greatest flexural strengths were found in dentin exposed to a 0.1% riboflavin solution for 1 minute followed by 1,600 mW/cm2 UVA irradiation for 10 minutes. Mineral loss and lesion depth were significantly lower in the RF/UVA group than in the control group. The microstructures of dentinal tubules and collagen networks after RF/UVA treatment retained their original forms after acidic and enzymatic degradation. In conclusion, RF/UVA treatment may be a new method for preventing root caries with promising prospects for clinical application.


Assuntos
Colágeno/metabolismo , Riboflavina/farmacologia , Cárie Radicular/prevenção & controle , Complexo Vitamínico B/farmacologia , Dentina/metabolismo , Humanos , Cárie Radicular/metabolismo , Raios Ultravioleta , Terapia Ultravioleta
8.
HLA ; 2018 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-29653015

RESUMO

We describe the identification of alternatively expressed HLA allele C*07:02:01:17N.

9.
Faraday Discuss ; 206: 523-534, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28933473

RESUMO

Various types of piperidinium ionic liquids (ILs) equipped with an oxygen atom-containing alkyl side chain on the positively charged nitrogen atom were systematically synthesized and their physical properties investigated. The thermal stability, viscosity, electrochemical window, and ion conductivity were influenced significantly by changing the position of the oxygen atom in the alkyl chain. Although the lowest viscosity was recorded for 1-((2-methoxyethoxy)methyl)-1-methylpiperidin-1-ium bis(trifluoromethylsulfonyl)amide ([PP1MEM][Tf2N]), 1-methyl-1-(2-propoxyethyl)piperidin-1-ium bis(trifluoromethylsulfonyl)amide ([PP1PE][Tf2N]) can be recommended as the best IL as an electrolyte due to its low viscosity and high thermal and electrochemical stability among the seven ILs tested.

10.
Clin Exp Immunol ; 191(3): 349-355, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28815559

RESUMO

To investigate the clinical significance of soluble tumour necrosis factor receptor (sTNF-R) II/I ratio as an indicator of the diagnosis of macrophage activation syndrome (MAS) complicating systemic juvenile idiopathic arthritis (s-JIA), we measured the serum sTNF-RI and II levels in 117 patients with s-JIA, including 29 patients with MAS, 15 with Epstein-Barr virus-induced haemophagocytic lymphohistiocytosis (EBV-HLH), 15 with Kawasaki disease (KD) and 28 healthy controls (HCs). We determined their correlation with measurements of disease activity and severity. Furthermore, we measured serum interleukin (IL)-18 levels in patients with EBV-HLH and compared these in levels in patients with MAS. The sTNF-RII/I ratio was elevated significantly in MAS and EBV-HLH patients compared with those in the acute phase of s-JIA and KD patients, whereas there were no significant differences between HCs and those in the acute phase of s-JIA. The sTNF-RII/I ratio increased profoundly as MAS developed and correlated positively with disease activity. Serum IL-18 levels were elevated significantly in MAS patients compared with EBV-HLH patients. The monitoring of serum IL-18 and sTNF-RII/I might be useful for the diagnosis of MAS and the differentiation between MAS and EBV-HLH.


Assuntos
Artrite Juvenil/diagnóstico , Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4/imunologia , Linfo-Histiocitose Hemofagocítica/diagnóstico , Síndrome de Ativação Macrofágica/diagnóstico , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Receptores Tipo II do Fator de Necrose Tumoral/sangue , Receptores Tipo I de Fatores de Necrose Tumoral/sangue , Doença Aguda , Artrite Juvenil/complicações , Artrite Juvenil/imunologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Progressão da Doença , Infecções por Vírus Epstein-Barr/imunologia , Feminino , Humanos , Interleucina-18/sangue , Linfo-Histiocitose Hemofagocítica/imunologia , Síndrome de Ativação Macrofágica/complicações , Síndrome de Ativação Macrofágica/imunologia , Masculino , Síndrome de Linfonodos Mucocutâneos/imunologia , Regulação para Cima
11.
Nanoscale Horiz ; 3(1): 28-34, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32254107

RESUMO

The nematic structuring of cellulose nanofibers (CNFs) is proposed as a nanostructural engineering tool for exploiting the potential of CNFs in conceptually new "transparent papers". The nematic-structured CNF papers exhibit superior mechanical properties, optical transparency, gas-barrier properties, heat transfer properties and electrical resistivity, compared with conventional randomly-structured CNF papers.

12.
Braz J Med Biol Res ; 50(7): e6037, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28591380

RESUMO

The Quechua term ayahuasca refers to a beverage obtained from decoctions of the liana Banisteriopsis caapi with leaves of Psychotria viridis. The ritualistic use of ayahuasca is becoming a global phenomenon, with some individuals using this beverage throughout life, including in old age. Cognitive impairment is a common manifestation during aging. There are conflicting reports on the ability of some ayahuasca compounds to exert neuroprotective or neurotoxic effects that could improve or impair learning and memory. Animal models provide a relevant and accessible means of investigating the behavioral effects of ayahuasca without the environmental conditions associated with the ritualistic use of the beverage. In this study, we investigated the influence of chronic ayahuasca exposure throughout aging on the spatial reference and habituation memories of mice. Twenty-eight male c57bl/6 mice (6 months old) received ayahuasca or water (1.5 mL/kg, orally) twice a week for 12 months and were tested in the Morris water maze (MWM), open field and elevated plus maze (EPM) tasks before and after treatment. During aging, there was significant impairment in the evocation (but not acquisition) of spatial reference memory and in habituation to the open field. There was also a decrease in locomotor activity in the open field and EPM tests, whereas the anxiety parameters were unaltered. Ayahuasca treatment did not alter any of these parameters associated with aging. These findings indicate that chronic exposure to ayahuasca during aging did not affect memory in mice.


Assuntos
Banisteriopsis/química , Bebidas , Locomoção/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Psychotria/química , Envelhecimento/fisiologia , Animais , Ansiedade/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Fatores de Tempo
13.
Eur J Clin Microbiol Infect Dis ; 36(10): 1839-1845, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28477235

RESUMO

Daptomycin (DAP) is widely used in the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infection. The emergence of DAP non-susceptible MRSA strains during therapy is a major concern in clinical settings. Recent studies revealed that MRSA spontaneously reverts to a subsequent methicillin-susceptible S. aureus (MSSA) strain. However, it is not clear whether DAP non-susceptible MRSA has the ability to revert to a susceptible strain. We obtained an MRSA strain pair, DAP non-susceptible strain and subsequent DAP susceptible strain, from a patient. To understand the underlying mechanism by which DAP non-susceptible MRSA reverts to a susceptible strain, we performed genetic and phenotypic analysis in the strain pair. Although whole-genome analysis revealed four missense mutations, including L826F in mprF, in both strains, the net cell-surface charge was similar between the DAP non-susceptible and susceptible strains. However, the thickness of the cell wall was higher in the DAP non-susceptible strain, which was decreased to the same level as the control after reversion to the DAP susceptible strain. Moreover, the non-susceptible strain showed higher mRNA expression of the two-component system (TCS), such as VraSR, yycG and GraS, with the up-regulated transcription levels of cell-wall biosynthesis-related genes. The expression levels of those genes were decreased after reversion to the susceptible strain. These results indicated that DAP non-susceptibility due to up-regulation of the TCS and cell-wall biosynthesis-related genes may be reversible by the discontinuation of DAP, leading to reversion to the DAP susceptible phenotype.


Assuntos
Antibacterianos/farmacologia , Parede Celular/metabolismo , Daptomicina/farmacologia , Regulação Bacteriana da Expressão Gênica , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Idoso , Análise Mutacional de DNA , Feminino , Perfilação da Expressão Gênica , Genótipo , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Mutação de Sentido Incorreto , Fenótipo
14.
J Dent Res ; 95(13): 1528-1534, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27523626

RESUMO

Advanced glycation end-products (AGEs) are generated via nonenzymatic glycation of dentinal collagen, resulting in accumulation of AGEs in dentin tissue. Since accumulated AGEs cause crosslinking between amino acid polypeptides in the collagen molecule and modify mechanical properties of dentinal collagen, the authors assumed that there would be a significant interaction between the generation of AGEs and progression of caries in dentin. To confirm such an interaction, spectroscopic imaging analyses (i.e., nanosecond fluorescence lifetime imaging and second harmonic generation light imaging) were performed in addition to biochemical and electron microscopic analyses in the present study. Seven carious human teeth were fixed in paraformaldehyde and cut longitudinally into 1-mm sections using a low-speed diamond saw for the following analyses. In transmission electron microscopy (TEM) analysis, nondecalcified specimens were embedded in epoxy resin and sliced into thin sections for observation. For the immunohistochemical analysis, the specimens were paraffin embedded after decalcification for 2 wk and sectioned with a microtome. Resultant sections were stained with anti-AGE and anticollagen antibodies. The demineralized specimens were used for spectroscopic analyses without additional treatment. For Western blotting analysis, specimens were separated into carious and sound dentin. Each specimen was homogenized with a bead crusher and an ultrasonic homogenizer and then treated with hydrochloric acid. In carious dentin, the collagen fibers showed an amorphous structure in the TEM image, and the AGEs were localized in the areas of bacterial invasion in the immunostaining image. The total amount of AGEs in carious dentin was higher than in sound dentin in Western blotting. The ultrastructure of type I collagen and total amount of AGEs varied markedly in the dentinal caries region. The fluorescence lifetime was shorter in the carious area than that in the sound areas, indicating an increase of AGEs in the carious area. The increase of AGEs could influence the progression of dentinal caries.


Assuntos
Colágeno/metabolismo , Cárie Dentária/patologia , Dentina/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Western Blotting , Colágeno/ultraestrutura , Reagentes de Ligações Cruzadas , Dentina/ultraestrutura , Progressão da Doença , Fluorescência , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Reação de Maillard , Microscopia Eletrônica
15.
Int J Cosmet Sci ; 38(6): 599-606, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27028411

RESUMO

OBJECTIVE: Washing the hands using cleansers with antiseptic materials is the most popular method for hand hygiene and helps maintain health by preventing food poisoning and bacterial infections. However, repeated hand washing tends to induce eczema of the hand, such as dryness, cracking and erythema. Moreover, eczema on the hand leads to increased levels in Staphylococcus aureus (S. aureus) on the skin surface in contrast to expectations. Thus, mild hand cleansers which induce less eczema even with repeated washings are desired. Here, we evaluated the efficacy of a hand cleanser formulated with alkyl ether sulphate (AES), alkyl ether carboxylic acid (AEC) and alkyl glucoside (AG) that contains isopropyl methylphenol (IPMP) on skin symptoms and S. aureus levels. METHODS: Eczema of the hand and the presence of S. aureus on the skin surface were analysed prior to and following 4 weeks of usage of the hand cleanser. A soap-based hand cleanser with IPMP was used as a reference cleanser. Eczema and cutaneous conditions were evaluated by visual grading, transepidermal water loss (TEWL), stratum corneum moisture-retention ability (MRA) and skin surface pH. RESULTS: The repeated use of the soap-based hand cleanser significantly worsened the hand dryness, scaling and cracks on the tips of the fingers and significantly increased the TEWL and decreased the MRA. In contrast, usage of the test cleanser only induced a significant increase in skin dryness but did not induce skin scaling or cracking and did not increase TEWL or decrease the MRA. Corresponding to these changes in skin symptoms, the presence of S. aureus increased the following use of the reference cleanser but not the test cleanser. There was no significant difference in skin surface pH between the two cleansers. Moreover, the increase in S. aureus was significantly correlated to the worsening of skin dryness and scaling. CONCLUSION: These results suggest that not only antimicrobial activity but also the mildness, which minimizes cutaneous effects, are important for hand cleansers to prevent the growth of S. aureus. The cleanser formulated with AES, AEC and AG containing IPMP is mild and is effective to promote hand hygiene.


Assuntos
Eczema/terapia , Mãos/microbiologia , Sabões , Staphylococcus aureus/crescimento & desenvolvimento , Feminino , Humanos
16.
Aliment Pharmacol Ther ; 43(1): 114-24, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26503582

RESUMO

BACKGROUND: The Wisteria floribunda agglutinin-positive human Mac-2-binding protein (WFA(+) -M2BP) is a new liver fibrosis glycobiomarker with unique fibrosis-related glyco-alteration. WFA(+) -M2BP is also a useful surrogate marker for the risk of developing hepatocellular carcinoma and for the liver functional reserve. AIM: To evaluate the diagnostic ability of WFA(+) -M2BP for liver fibrosis in the clinical setting and the clinical utility of WFA(+) -M2BP for predicting the efficacy of direct-acting anti-viral (DAA) treatment for chronic hepatitis C patients. METHODS: The study included 159 genotype 1 hepatitis C patients who received DAA-based treatment (telaprevir or simeprevir) combined with pegylated-interferon alpha plus ribavirin (108 telaprevir- and 51 simeprevir-based triple treatment). The relation between baseline serum WFA(+) -M2BP and treatment efficacy was evaluated. RESULTS: The serum WFA(+) -M2BP level significantly increased with the progress of liver fibrosis. Area under the receiver operating characteristic curve analysis identified 2.17 as the cut-off index (COI) for WFA(+) -M2BP for diagnosing advanced fibrosis. The sustained virological response (SVR) rate was significantly, negatively correlated with the serum WFA(+) -M2BP level. Multiple logistic regression analysis found a low serum WFA(+) -M2BP level (<2.17 COI) to be independently associated with SVR (odds ratio, 4.35, P = 0.027). Even for prior nonresponders and patients with the interleukin-28B minor allele or histological advanced fibrosis, treatment outcome was favourable for patients with a low serum WFA(+) -M2BP level. CONCLUSION: Serum WFA(+) -M2BP is a non-invasive liver fibrosis marker useful for predicting the efficacy of DAA-based triple therapy for chronic hepatitis C patients.


Assuntos
Antígenos de Neoplasias/sangue , Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Cirrose Hepática/patologia , Glicoproteínas de Membrana/sangue , Lectinas de Plantas/sangue , Polietilenoglicóis/uso terapêutico , Receptores de N-Acetilglucosamina/sangue , Idoso , Biomarcadores , Carcinoma Hepatocelular/tratamento farmacológico , Feminino , Hepacivirus/genética , Hepatite C Crônica/sangue , Humanos , Interferon alfa-2 , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Simeprevir/uso terapêutico , Resultado do Tratamento
17.
Int J Infect Dis ; 34: 119-21, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25841635

RESUMO

A food-poisoning outbreak due to enterohemorrhagic Escherichia coli (EHEC) occurred in Toyama, Japan. The case of a 26-year-old pregnant woman with hemolytic-uremic syndrome who developed acute encephalopathy due to EHEC infection after eating raw meat is presented herein. On day 2 following admission, a cesarean section was performed because of a non-reassuring fetal status. Fecal bacterial culture confirmed an O111/O157 superinfection. Intensive care therapies including continuous hemodiafiltration and plasma exchange were performed. After the operation, the patient developed encephalopathy for which steroid pulse therapy was added. Her condition improved gradually and she was discharged 55 days after delivery.


Assuntos
Encefalopatias/diagnóstico , Encéfalo/patologia , Escherichia coli Êntero-Hemorrágica/isolamento & purificação , Epidemias , Doenças Transmitidas por Alimentos/complicações , Síndrome Hemolítico-Urêmica/complicações , Complicações Infecciosas na Gravidez/diagnóstico , Adulto , Encefalopatias/microbiologia , Encefalopatias/terapia , Citocinas/sangue , Fezes/microbiologia , Feminino , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/terapia , Hemodiafiltração , Síndrome Hemolítico-Urêmica/terapia , Humanos , Japão/epidemiologia , Carne/microbiologia , Neuroimagem , Troca Plasmática , Gravidez , Complicações Infecciosas na Gravidez/terapia , Resultado do Tratamento
18.
Sci Technol Adv Mater ; 16(2): 025001, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27877770

RESUMO

Controlling the thermal radiation spectra of materials is one of the promising ways to advance energy system efficiency. It is well known that the thermal radiation spectrum can be controlled through the introduction of periodic surface microstructures. Herein, a method for the large-area fabrication of periodic microstructures based on multi-step wet etching is described. The method consists of three main steps, i.e., resist mask fabrication via photolithography, electrochemical wet etching, and side wall protection. Using this method, high-aspect micro-holes (0.82 aspect ratio) arrayed with hexagonal symmetry were fabricated on a stainless steel substrate. The conventional wet etching process method typically provides an aspect ratio of 0.3. The optical absorption peak attributed to the fabricated micro-hole array appeared at 0.8 µm, and the peak absorbance exceeded 0.8 for the micro-holes with a 0.82 aspect ratio. While argon plasma etching in a vacuum chamber was used in the present study for the formation of the protective layer, atmospheric plasma etching should be possible and will expand the applicability of this new method for the large-area fabrication of high-aspect materials.

19.
Radiat Prot Dosimetry ; 164(3): 181-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25209996

RESUMO

The authors report the results of an indirect comparison of the standards of absorbed dose to water in high-energy photon beams from a clinical linac and (60)Co radiation beam performed between the National Metrology Institute of Japan (NMIJ) and the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA). Three ionisation chambers were calibrated by the NMIJ in April and June 2013 and by the ARPANSA in May 2013. The average ratios of the calibration coefficients for the three ionisation chambers obtained by the NMIJ to those obtained by the ARPANSA were 0.9994, 1.0040 and 1.0045 for 6-, 10- and 15-MV (18 MV at the ARPANSA) high-energy photon beams, respectively. The relative standard uncertainty of the value was 7.2 × 10(-3). The ratio for (60)Co radiation was 0.9986(66), which is consistent with the results published in the key comparison of BIPM.RI(I)-K4.


Assuntos
Calibragem/normas , Aceleradores de Partículas/normas , Fótons , Radiometria/normas , Radioterapia de Alta Energia/normas , Água/química , Academias e Institutos , Austrália , Radioisótopos de Cobalto/análise , Radioisótopos de Cobalto/normas , Humanos , Japão , Aceleradores de Partículas/instrumentação , Radiometria/instrumentação , Radioterapia de Alta Energia/instrumentação , Padrões de Referência , Reprodutibilidade dos Testes
20.
J Dent Res ; 94(1): 140-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25376720

RESUMO

In this study, we first investigated the expressions of Jagged1, Notch2, the receptor activator of nuclear factor-kappa B ligand (RANKL), and interleukin (IL)-6 in areas of root resorption during experimental tooth movement in rats in vivo. We then assessed the effects of compression force (CF) with or without GSI (an inhibitor of Notch signaling) on Jagged1, RANKL, and IL-6 release from human periodontal ligament (hPDL) cells. Twelve male 6-wk-old Wistar rats were subjected to an orthodontic force of 50 g to induce mesially tipping movement of the upper first molars for 7 d. The expression levels of tartrate-resistant acid phosphatase, Jagged1, Notch2, IL-6, and RANKL proteins in the dental root were determined using an immunohistochemical analysis. Furthermore, the effects of the CF on Jagged1, IL-6, and RANKL production were investigated using hPDL cells in vitro. The effects of the cell-conditioned medium obtained from the hPDL cells subjected to CF (CFM) and Jagged 1 on osteoclastogenesis of human osteoclast precursor cells (hOCPs) were also investigated. Under the conditions of experimental tooth movement in vivo, resorption lacunae with multinucleated cells were observed in the 50 g group. In addition, immunoreactivity for Jagged1, Notch2, IL-6, and RANKL was detected on day 7 in the PDL tissue subjected to the orthodontic force. In the in vitro study, the compression force increased the production of Jagged1, IL-6, and RANKL from the hPDL cells, whereas treatment with GSI inhibited the production of these factors in vitro. The osteoclastogenesis increased with the CFM and rhJagged1, and the increase in the osteoclastogenesis was almost inhibited by GSI. These results suggest that the Notch signaling response to excessive orthodontic forces stimulates the process of root resorption via RANKL and IL-6 production from hPDL cells.


Assuntos
Proteínas de Ligação ao Cálcio/análise , Peptídeos e Proteínas de Sinalização Intercelular/análise , Interleucina-6/análise , Proteínas de Membrana/análise , Ligamento Periodontal/química , Ligante RANK/análise , Receptor Notch2/análise , Reabsorção da Raiz/etiologia , Transdução de Sinais/fisiologia , Fosfatase Ácida/análise , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Animais , Biomarcadores/análise , Técnicas de Cultura de Células , Meios de Cultivo Condicionados , Fibroblastos/patologia , Humanos , Isoenzimas/análise , Proteína Jagged-1 , Masculino , Oligopeptídeos/farmacologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/patologia , Ligamento Periodontal/patologia , Distribuição Aleatória , Ratos , Ratos Wistar , Receptor Notch2/antagonistas & inibidores , Reabsorção da Raiz/patologia , Proteínas Serrate-Jagged , Transdução de Sinais/efeitos dos fármacos , Fosfatase Ácida Resistente a Tartarato , Técnicas de Movimentação Dentária/efeitos adversos , Raiz Dentária/química
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