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1.
Dent J (Basel) ; 12(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38275677

RESUMO

The current digital dentistry workflow has streamlined dental restoration production, but the effectiveness of digital virtual design and 3D printing for restorations still needs evaluation. This study explores the impact of model-free digital design and 3D-printing placement angles on restorations, including single crowns and long bridges produced with and without casts. The restorations are 3D printed using resin at placement angles of 0°, 60°, and 90°. Each group of samples was replicated ten times, resulting in a total of 120 restorations. The Root Mean Square Error (RMSE) value was used to evaluate the surface integrity of the restoration. In addition, the contact space, edge gap, and occlusal space of restorations produced by different processes were recorded. The results indicate that there was no significant difference in the RMSE value of the crown group (p > 0.05). Changing the bridge restoration angle from 0° to 90° resulted in RMSE values increasing by 2.02 times (without casts) and 2.39 times (with casts). Furthermore, the marginal gaps in the crown group were all less than 60 µm, indicating good adaptation. In contrast, the bridge group showed a significant increase in marginal gaps at higher placement angles (p > 0.05). Based on the findings, virtual fabrication without casts does not compromise the accuracy of dental restorations. When the position of the long bridge exceeds 60 degrees, the error will increase. Therefore, designs without casts and parallel placement result in higher accuracy for dental restorations.

2.
Front Psychol ; 13: 836865, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35936276

RESUMO

While the Ganong lexicality effect has been observed for phonemic and tonal categorization, the effects of frequency and markedness are less clear, especially in terms of tonal categorization. In this study, we use Mandarin Chinese to investigate the effects of lexicality, tone frequency and markedness. We examined Mandarin speakers' tonal categorization of tokens on all possible tonal continua with one end being a word and the other being a tonotactic gap (i.e., an unattested syllable-tone combination). The results of a forced-choice identification experiment showed a general bias against the gap endpoints, with the noted exception of continua involving T4 (X51), the most frequent lexical tone. Specifically, when T4 served as the gap endpoint, no obvious bias against it was observed regardless of its lexical status. Moreover, on the T3-T4 continua, there was an apparent bias against T3 (X214), the tone with the most complex contour, again, regardless of lexicality, suggesting a strong markedness effect. Taken together, the results of this study show the individual effects of lexicality, tone frequency and markedness, as well as their interactions, which contribute to our understanding of tonal categorization in relation to lexical statistics (tone frequency) and phonology (markedness).

3.
BMC Ophthalmol ; 22(1): 168, 2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35421960

RESUMO

BACKGROUND: Posterior ischemic optic neuropathy (PION) is a rare cause of visual loss, especially in young patients who are more prone to inflammatory demyelinating optic neuritis (ON) compared to other types of optic neuropathy. The diagnosis of PION is usually a diagnosis of exclusion; however, the emergence of modern neuroimaging technique with diffuse-weighted image (DWI) and apparent diffusion coefficient (ADC) sequences in Magnetic Resonance Imaging (MRI) provides more evidence for accurate diagnosis and management. CASE PRESENTATION: A 30-year-old man with a history of hypertension and chronic renal failure secondary to glomerulonephritis presented with sudden onset of blurred vision, dyschromatopsia, pain, and positive relative afferent pupillary defect (RAPD) in the left eye for 1 week. He was initially admitted for steroid pulse therapy and was further monitored due to suspicion of optic neuritis oculus sinister (OS). However, his brain MRI revealed a focal high hyperintensity signal at the left optic nerve on the T2 DWI series. The area was corresponded with the hypointensity area in the ADC series, which was a powerful clue for PION. We explained the poor visual prognosis of PION to the patient after finishing steroid pulse therapy and referred him to the Nephrology and Neurology department for hypertension control to prevent additional hypertension related complication. CONCLUSIONS: The diagnosis of PION is usually a diagnosis of exclusion; however, carefully interpreting the DWI and ADC sequence in MRI may give the clinician more evidence for the definite diagnosis and leads to proper management.


Assuntos
Hipertensão , Neurite Óptica , Neuropatia Óptica Isquêmica , Adulto , Humanos , Hipertensão/complicações , Imageamento por Ressonância Magnética , Masculino , Neurite Óptica/diagnóstico , Neurite Óptica/etiologia , Neuropatia Óptica Isquêmica/etiologia , Esteroides , Transtornos da Visão
4.
Opt Lett ; 43(2): 271-274, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29328257

RESUMO

Electrically tunable lenses offer the possibility to control the focal distance by applying an electric field. Different liquid crystal tunable lenses have been demonstrated. In order to minimize lens aberrations, multi-electrode designs allow us to fine-tune the applied voltages for every possible focal distance. In this Letter, we provide a novel multi-electrode design in which only one lithography step is necessary, thereby offering a greatly simplified fabrication procedure compared to earlier proposed designs. The key factor is the use of a high-permittivity layer, in combination with floating electrodes.

5.
Chemosphere ; 100: 71-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24461425

RESUMO

This study attempts to elucidate the relationship between neurological effects and mercury/methylmercury concentrations in various biomarkers, including meconium, hair, fingernail, and toenail. Eight-three mother-infant pairs were recruited between August 2008 and December 2009, and follow-up examinations on these children were completed after three years. The Bayley Scales of Infant and Toddler Development (Bayley-III) for evaluating the cognitive, language, and motor development of three-year-old children were calculated and validated. The geometric mean of the total mercury concentration in meconium was 89.6 ng g(-1). The methylmercury concentrations in hair, fingernail, and toenail samples were 1.96, 0.64, and 0.55 µg g(-1), respectively. Seventy percent of children had hair methylmercury concentrations exceeding the U.S. environmental protection agency (EPA) reference of 1 µg g(-1). A significantly positive correlation was obtained between methylmercury levels in hair, fingernail, and toenail. These methylmercury levels were also significantly positively correlated with the children's fish intake and negatively correlated with a Bayley-III scale score of expressive language. The prenatal mercury exposure, however, did not show significant influence on neurological development. High fish consumption appears to be a critical risk factor for methylmercury levels in children and may cause a lower expressive language score.


Assuntos
Exposição Ambiental/efeitos adversos , Mercúrio/toxicidade , Compostos de Metilmercúrio/toxicidade , Testes Neuropsicológicos , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Adulto , Animais , Pré-Escolar , Cognição/efeitos dos fármacos , Feminino , Peixes , Humanos , Lactente , Masculino , Mercúrio/metabolismo , Compostos de Metilmercúrio/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Taiwan , Estados Unidos
6.
Int J Equity Health ; 12: 87, 2013 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-24165541

RESUMO

INTRODUCTION: The concept of social cohesion has invoked debate due to the vagueness of its definition and the limitations of current measurements. This paper attempts to examine the concept of social cohesion, develop measurements, and investigate the relationship between social cohesion and individual health. METHODS: This study used a multilevel study design. The individual-level samples from 29 high-income countries were obtained from the 2000 World Value Survey (WVS) and the 2002 European Value Survey. National-level social cohesion statistics were obtained from Organization of Economic Cooperation and Development datasets, World Development Indicators, and Asian Development Bank key indicators for the year 2000, and from aggregating responses from the WVS. In total 47,923 individuals were included in this study. The factor analysis was applied to identify dimensions of social cohesion, which were used as entities in the cluster analysis to generate a regime typology of social cohesion. Then, multilevel regression models were applied to assess the influences of social cohesion on an individual's self-rated health. RESULTS AND DISCUSSION: Factor analysis identified five dimensions of social cohesion: social equality, social inclusion, social development, social capital, and social diversity. Then, the cluster analysis revealed five regimes of social cohesion. A multi-level analysis showed that respondents in countries with higher social inclusion, social capital, and social diversity were more likely to report good health above and beyond individual-level characteristics. CONCLUSIONS: This study is an innovative effort to incorporate different aspects of social cohesion. This study suggests that social cohesion was associated with individual self-rated after controlling individual characteristics. To achieve further advancement in population health, developed countries should consider policies that would foster a society with a high level of social inclusion, social capital, and social diversity. Future research could focus on identifying possible pathways by which social cohesion influences various health outcomes.


Assuntos
Nível de Saúde , Apoio Social , Autoavaliação Diagnóstica , Análise Fatorial , Humanos , Análise Multinível , Classe Social , Isolamento Social , Fatores Socioeconômicos
7.
J Epidemiol Community Health ; 66(7): e23, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21880645

RESUMO

BACKGROUND: This longitudinal study builds on the cross-sectional work of Karim et al and examines the influence of welfare state regime on population health with a particular focus on East Asian welfare states (eg, Hong Kong, Japan, Korea, Singapore and Taiwan). METHODS: Data were extracted from the Organisation of Economic Co-operation and Development Data Set, World Development Indicators and Asian Development Bank's key indicators from 1980 to 2006. Infant mortalities and life expectancy were used as health-outcome varables. Thirty-one countries were categorised into six types of welfare regimes: Scandinavian, Anglo-Saxon, Bismarckian, Southern, Eastern European and East Asian. Mixed models were applied to analyse the data with repeated measurements. RESULTS: In keeping with Karim et al, Scandinavian and Eastern European welfare states have lower and higher infant mortalities respectively compared with East Asian welfare states. Eastern European welfare states had a lower life expectancy than East Asian welfare states. Most welfare states had a higher social, health and education expenditure, and higher densities of physicians than East Asian welfare states. CONCLUSION: East Asian welfare states did not have worse health than most welfare states. Future studies should continue to incorporate East Asian countries in the typology of welfare regimes that include more social, economic, political and healthcare system characteristic variables to provide insight on the mechanism by which welfare-state regimes influence population health.


Assuntos
Governo , Mortalidade Infantil , Expectativa de Vida/tendências , Seguridade Social , Idoso , Ásia Oriental/epidemiologia , Feminino , Humanos , Recém-Nascido , Estudos Longitudinais , Masculino , Classe Social
8.
Transgenic Res ; 20(1): 73-83, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20373020

RESUMO

Multiple advantages-including the short generation time, large numbers of fertilized eggs, low cost of cultivation and easy maintenance favor the use of fish as bioreactors for the production of pharmaceutical proteins. In the present study, zebrafish eggs were used as bioreactors to produce mature tilapia insulin-like growth factors (IGFs) proteins using the oocyte-specific zona pellucida (zp3) promoter. The chimeric expression plasmids, pT2-ZP-tIGFs-IRES-hrGFP, in which hrGFP was used as reporter of tilapia IGFs expression, were designed to established Tg (ZP:tIGFs:hrGFP) transgenic lines for the expression of tilapia IGF-1 and IGF-2. Recombinant tilapia IGF-1 and IGF-2 were expressed as soluble forms in cytoplasm of fertilized eggs. The content level of tilapia IGF-1 and IGF-2 were 6.5 and 5.0% of the soluble protein, respectively. Using a simple Ni-NTA affinity chromatography purification process, 0.58 and 0.49 mg of purified tilapia IGF-1 and IGF-2 were obtained, respectively, from 650 fertilized eggs. The biological activity of the purified tilapia IGF-1 and IGF-2 was confirmed via a colorimetric bioassay to monitor the growth stimulation of zebrafish embryonic cells (ZF4), tilapia ovary cells (TO-2) and human osteosarcoma epithelial cells (U2OS). These results demonstrate that the use of zebrafish eggs as bioreactors is a promising approach for the production of biological recombinant proteins.


Assuntos
Oócitos/metabolismo , Somatomedinas/biossíntese , Tilápia/metabolismo , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Reatores Biológicos , Linhagem Celular , Humanos , Fator de Crescimento Insulin-Like I/biossíntese , Fator de Crescimento Insulin-Like I/química , Fator de Crescimento Insulin-Like II/biossíntese , Fator de Crescimento Insulin-Like II/química , Oócitos/citologia , Óvulo/citologia , Óvulo/metabolismo , Proteínas Recombinantes/biossíntese , Somatomedinas/química , Tilápia/genética , Peixe-Zebra/crescimento & desenvolvimento , Zona Pelúcida/metabolismo
9.
Comp Biochem Physiol B Biochem Mol Biol ; 151(4): 373-80, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18790071

RESUMO

Gonadotropin-releasing hormone (GnRH) is a neuropeptide that plays a major role in releasing pituitary gonadotropin and controlling vertebrate reproduction. In this study, three GnRH cDNAs, GnRH-I (sbGnRH; 348 bp), GnRH-II (cGnRH-II; 557 bp), and GnRH-III (sGnRH; 483 bp), were cloned from the brain of the silver sea bream (Sparus sarba). In order to understand how the expression of the GnRH isoforms was regulated in the brain, the promoter of each gene was cloned and analyzed. We found regulatory motifs in the promoters that were conserved in the GnRH promoters of tilapia and zebrafish, suggesting that these motifs play a critical role in GnRH regulation. We performed functional analyses and examined tissue-specific expression for each GnRH promoter using EGFP reporter fusions in zebrafish. The GnRH-I promoter was active in the forebrain area, including the olfactory bulb-terminal nerve area and peripheral preoptic areas; the GnRH-II promoter was active in the midbrain; and the GnRH-III promoter was active in the olfactory bulb. These results show that the GnRH promoters of the silver sea bream GnRH genes exhibit tissue-specific activity.


Assuntos
Química Encefálica , Hormônio Liberador de Gonadotropina/genética , Regiões Promotoras Genéticas/genética , Animais , Clonagem Molecular , Sequência Conservada , Mesencéfalo , Bulbo Olfatório , Área Pré-Óptica , Prosencéfalo , Isoformas de Proteínas , Dourada
10.
J Neurosci Res ; 85(13): 2950-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17628501

RESUMO

Bone morphogenetic proteins (BMPs), members of the TGF-beta superfamily, have been implicated in nervous system development and in response to injury. Previous studies have shown that recombinant BMP7 can enhance dendritic growth and protect cultured neurons from oxidative stress. Because of the presence of extracellular BMP antagonists, BMP7 seems to act locally. Therefore, the present study uses BMP7 overexpression using adenovirus (Ad)-mediated gene transfer to examine its effect in mixed neuronal cultures. Enhanced BMP7 expression selectively induces neuronal CGRP expression in a time-dependent manner. BMP7 overexpression not only significantly protects cultures from H2O2 toxicity but reduces lipopolysaccharide (LPS) stimulation. Concurrently, it profoundly reduces microglial numbers, but increases oligodendroglial and endothelial cells. Together, low-dose and continuously expressed BMP7 is both neuroprotective and differentiation-inductive.


Assuntos
Adenoviridae/fisiologia , Proteínas Morfogenéticas Ósseas/fisiologia , Diferenciação Celular/fisiologia , Neuroglia/fisiologia , Neurônios/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Animais , Proteína Morfogenética Óssea 7 , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Contagem de Células/métodos , Células Cultivadas , Córtex Cerebral/citologia , Técnicas de Cocultura/métodos , Ectodisplasinas/metabolismo , Embrião de Mamíferos , Humanos , Peróxido de Hidrogênio/farmacologia , Lipopolissacarídeos/farmacologia , Proteínas do Tecido Nervoso/metabolismo , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transfecção/métodos
11.
J Cell Biochem ; 85(3): 572-82, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11967997

RESUMO

Restenosis may develop in response to cytokine activation and smooth muscle cell proliferation. Ginkgo biloba extract (EGb) has been used to treat cardiovascular and cerebrovascular diseases. In the present study, the effects of EGb on the growth of cultured vascular smooth muscle cells (VSMC), as well as on the expression of interleukin-1beta (IL-1beta) and the intimal response in balloon-injured arteries of cholesterol-fed rabbits, were investigated. Using bromodeoxyuridine incorporation as an index of cell proliferation, EGb was found to inhibit serum-induced mitogenesis of cultured rat aorta VSMC in a dose-dependent manner. In vivo, EGb and probucol ( positive control) reduced the atheroma area in thoracic aortas of male New Zealand white rabbits fed a 2% cholesterol diet for 6 weeks with balloon denudation of the abdominal aorta being performed at the end of the third week. Intimal hyperplasia, expressed as the intimal/medial area ratio, in the abdominal aortas was significantly inhibited in the both the EGb group (0.61 +/- 0.06) and the probucol group (0.55 +/- 0.03) compared to the C group (0.87 +/- 0.02). In the balloon-injured abdominal aorta, both EGb and probucol significantly reduced IL-1beta mRNA and protein expression and the percentage of proliferating cells. The inhibitory effects of EGb on the intimal response might be attributed to its antioxidant capacity. EGb may have therapeutic potential for the prevention of restenosis after angioplasty.


Assuntos
Angioplastia com Balão/efeitos adversos , Colesterol/farmacologia , Ginkgo biloba , Músculo Liso Vascular/efeitos dos fármacos , Extratos Vegetais/farmacologia , Túnica Íntima/efeitos dos fármacos , Animais , Anticolesterolemiantes/farmacologia , Aorta Abdominal/efeitos dos fármacos , Aorta Abdominal/lesões , Aorta Abdominal/patologia , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/patologia , Arteriosclerose/tratamento farmacológico , Arteriosclerose/patologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Cobre/farmacologia , Modelos Animais de Doenças , Interleucina-1/genética , Interleucina-1/metabolismo , Lipoproteínas LDL/efeitos dos fármacos , Lipoproteínas LDL/metabolismo , Masculino , Músculo Liso Vascular/citologia , Probucol/farmacologia , Coelhos , Ratos , Ratos Sprague-Dawley , Túnica Íntima/lesões , Túnica Íntima/patologia
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