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1.
Endocr Connect ; 11(2)2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-35015696

RESUMO

Background: Graves' orbitopathy (GO) is an autoimmune disease with mechanical impairment of orbital muscles and lacrimal gland dysfunction. The frequently used methods of assessing GO activity include Clinical Activity Score (CAS), CT, and MRI. These approaches are mainly associated with orbital muscles; however, there are not many studies that focus on the lacrimal gland inflammation of GO patients. Objective: The aim of this study is to assess the usefulness of 99mTc-DTPA single-photon emission (SPE) CT/CT in evaluating the lacrimal gland inflammation in GO, as compared with other methods. Methods: A retrospective analysis of 48 patients with active GO compared with 33 controls was conducted. All subjects underwent clinical-endocrinological analyses, CAS evaluation, CT scans, and SPECT/CT examination. Lacrimal gland dimensions were determined and analyzed. Results: The lacrimal glands in patients with GO were significantly larger in all measured dimensions (P < 0.001) on CT scans relative to those in controls. Increased lacrimal gland diethylene triamine pentaacetic acid (DTPA) uptake ratios (P < 0.001) were displayed in active GO patients compared to controls and were also correlated with thyrotropin receptor antibody levels. The cut-off value for discriminating active and inactive disease was calculated to be 1.735, with specificity of 82.6% and sensitivity of 74.2%. SPECT/CT uptake ratios and CAS values were positively correlated in all GO patients. SPECT/CT uptake ratios were also positively correlated with CT measurements including lacrimal gland volume and coronal width in GO patients. Conclusions: These data indicated that lacrimal gland SPECT/CT images can serve as a good tool for assessing the inflammation and disease activity of GO.

2.
Endocr Connect ; 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32508316

RESUMO

BACKGROUND: The pathogenesis underlying the alterations of orbital architecture in Graves' orbitopathy (GO) is not yet fully understood. The present study aimed to investigate the association of DNA methylation in peripheral blood and orbital volumetry in Chinese patients with GO. METHODS: A total of 35 GO subjects (70 orbits) were subjected to computed tomography (CT) scan. The total cross-sectional area of the extraocular muscles (orbital muscles, OM), total orbit area (TOA), and the exophthalmometry were measured, and OM/TOA ratio was calculated. Targeted bisulfite sequencing was performed on seven candidate genes. RESULTS: No significant correlation was established between the DNA methylation levels of these genes and exophthalmometry. The MBP methylation level was found to be correlated with OM/TOA ratio (P<0.05). Multiple linear regression analysis on parameters, including age, sex, TRAb, duration of GO, and DNA methylation levels of seven genes with OM/TOA ratio confirmed that MBP and OM/TOA ratio had a significant correlation (P<0.05). The partial least squares analysis showed that the top three genes with the highest loadings were MBP, BOLL, and BECN1, and OM/TOA ratio affected the DNA methylation block than exophthalmometry. CONCLUSIONS: This study provided preliminary evidence that MBP is a potential gene associated with OM enlargement in GO patients according to the combination of DNA methylation sequencing and orbital CT measurement.

3.
Microsc Res Tech ; 82(7): 953-960, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30636063

RESUMO

A thorough understanding of inner ear anatomy is important for investigators. However, investigation of the mouse inner ear is difficult due to the limitations of imaging techniques. X-ray phase contrast tomography increases contrast 100-1,000 times compared with conventional X-ray imaging. This study aimed to investigate inner ear anatomy in a fresh post-mortem mouse using X-ray phase contrast tomography and to provide a comprehensive atlas of microstructures with less tissue deformation. All experiments were performed in accordance with our institution's guidelines on the care and use of laboratory animals. A fresh mouse cadaver was scanned immediately after sacrifice using an inline phase contrast tomography system. Slice images were reconstructed using a filtered back-projection (FBP) algorithm. Standardized axial and coronal planes were adjusted with a multi-planar reconstruction method. Some three-dimensional (3D) objects were reconstructed by surface rendering. The characteristic features of microstructures, including otoconia masses of the saccular and utricular maculae, superior and inferior macula cribrosae, single canal, modiolus, and osseous spiral lamina, were described in detail. Spatial positions and relationships of the vestibular structures were exhibited in 3D views. This study investigated mouse inner ear anatomy and provided a standardized presentation of microstructures. In particular, otoconia masses were visualized in their natural status without contrast for the first time. The comprehensive anatomy atlas presented in this study provides an excellent reference for morphology studies of the inner ear.


Assuntos
Orelha Interna/anatomia & histologia , Microscopia de Contraste de Fase , Tomografia Computadorizada por Raios X , Animais , Orelha Interna/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional/instrumentação , Imageamento Tridimensional/métodos , Camundongos , Membrana dos Otólitos/anatomia & histologia , Membrana dos Otólitos/diagnóstico por imagem
4.
Artigo em Inglês | MEDLINE | ID: mdl-29994633

RESUMO

Existing learning-based atmospheric particle-removal approaches such as those used for rainy and hazy images are designed with strong assumptions regarding spatial frequency, trajectory, and translucency. However, the removal of snow particles is more complicated because they possess additional attributes of particle size and shape, and these attributes may vary within a single image. Currently, hand-crafted features are still the mainstream for snow removal, making significant generalization difficult to achieve. In response, we have designed a multistage network named DesnowNet to in turn deal with the removal of translucent and opaque snow particles. We also differentiate snow attributes of translucency and chromatic aberration for accurate estimation. Moreover, our approach individually estimates residual complements of the snow-free images to recover details obscured by opaque snow. Additionally, a multi-scale design is utilized throughout the entire network to model the diversity of snow. As demonstrated in the qualitative and quantitative experiments, our approach outperforms state-of-the-art learning-based atmospheric phenomena removal methods and one semantic segmentation baseline on the proposed Snow100K dataset. The results indicate our network would benefit applications involving computer vision and graphics.

5.
IEEE Trans Image Process ; 25(7): 2971-2982, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-28113172

RESUMO

Digital multitoning is an extension of halftoning for rendering more than two tones at each pixel for higher image quality. Although a lot of effort has been put in generating dispersed dots previously, the blue-noise feature can hardly be achieved for those printers utilizing the electrophotography (EP) process to avoid the physically unstable isolated dots. To overcome this issue, Chandu et al. proposed a screening method for yielding green-noise dot clusters, yet noisy multitone texture was accompanied. This degrades the visual quality and the stability of tone rendering. In this paper, a significantly improved homogeneity of clustered dots can be achieved by the proposed screening method based upon the new inter-iterative clustered-dot direct multi-bit search algorithm. Compared with the former approaches, the inter-iteration design leads to less error by the updated initial multitone patterns. As demonstrated in the experimental results, both of the high homogenous multitone texture and less noisy perception at all absorptance levels are offered in contrast to the former Chandu et al.'s results. The high-quality output proves it as a very competitive candidate for EP printers, e.g., laser printers.

6.
IEEE Trans Image Process ; 24(11): 4581-91, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26316124

RESUMO

Compared with the error diffusion, dot diffusion provides an additional pixel-level parallelism for digital halftoning. However, even though its periodic and blocking artifacts had been eased by the previous works, it was still far from satisfactory in terms of the blue noise spectrum perspective. In this paper, we strengthen the relation among the pixel locations of the same processing order by an iterative halftoning method, and the results demonstrate a significant improvement. Moreover, a new approach of deriving the averaged power spectrum density is proposed to avoid the regular sampling of the well-known Bartlett's procedure which inaccurately presents the halftone periodicity of certain halftoning techniques with parallelism. As a result, the proposed dot diffusion is substantially superior to the state-of-the-art parallel halftoning methods in terms of visual quality and artifact-free property, and competitive runtime to the theoretical fastest ordered dithering is offered simultaneously.

7.
IEEE Trans Image Process ; 24(11): 4312-21, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26219093

RESUMO

Error diffusion is an efficient halftone method for mainly being applied on printers. The promising high image quality and processing efficiency endorse it as a popular and competitive candidate in halftoning and multitoning applications. The multitoning is an extension of halftoning, adopting more than two-tone levels for the improvement of the similarity between an original image and the converted image. Yet, the banding effect, indicating the areas with discontinuous tone level, disturbs the visual perception, and thus seriously degrades image quality. To solve the banding effect, the tone-replacement strategy is proposed in this paper. As documented in the experimental results, excellent tone-similarity as that of the original image and promising reconstructed dot-distribution can be provided simultaneously. Comparing with the former banding-free methods, the apparent improvements/features suggest that the proposed method can be a very competitive candidate for multitoning applications.

8.
IEEE Trans Image Process ; 22(11): 4522-31, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23955745

RESUMO

Look-up table (LUT) halftoning is an efficient way to construct halftone images and approximately simulate the dot distribution of the learned halftone image set. In this paper, a general mechanism named multiple look-up table (MLUT) halftoning is proposed to generate the halftones of direct binary search (DBS), whereas the high efficient characteristic of the LUT is still preserved. In the MLUT, the standard deviation is adopted as an important feature to classify various tables. In addition, the proposed quick standard deviation evaluation is employed to yield an extremely low computational complexity in calculating the standard deviation. In the parameter optimization, the autocorrelation is adopted because it can fully characterize the periodicity of dot distribution. Experimental results demonstrate that the dot distribution generated by the proposed method approximates to that of the DBS, which enables the proposed scheme as a very competitive candidate in the copying and printing industry.


Assuntos
Algoritmos , Cor , Colorimetria/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Armazenamento e Recuperação da Informação/métodos , Reconhecimento Automatizado de Padrão/métodos , Gráficos por Computador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
IEEE Trans Image Process ; 22(3): 1199-208, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23192555

RESUMO

In this paper, a new class tiling designed dot diffusion along with the optimized class matrix and diffused matrix are proposed. The result of this method presents a nearly periodic-free halftone when compared to the former schemes. Formerly, the class matrix of the dot diffusion is duplicated and orthogonally tiled to fulfill the entire image for further thresholding and quantized-error diffusion, which accompanies subsequent periodic artifacts. In our observation, this artifact can be solved by manipulating the class tiling with comprising rotation, transpose, and alternatively shifting of the class matrices. As documented in the experimental results, the proposed dot diffusion has been compared with the former halftoning methods with parallelism in terms of image quality, processing efficiency, periodicity, and memory consumption; the proposed dot diffusion exhibits as a very competitive candidate in the printing/display market.


Assuntos
Algoritmos , Gráficos por Computador , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Impressão/métodos , Cor , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Asian-Australas J Anim Sci ; 26(1): 30-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25049702

RESUMO

The myostatin (MSTN) gene, as a negative regulator of skeletal muscle growth, has been proposed to be associated with production traits in farm animals. In the present study, a T/C variant at -125 bp (relative to ATG start codon) of 5'regulatory region of rabbit MSTN was identified by direct sequencing. Two hundred and twenty two rabbits, which were randomly sampled from 3 breeds (Ira rabbits, Champagne rabbits and Tianfu black rabbits), were genotyped by high-resolution melting (HRM). Comparing the genotyping results of 47 samples with direct sequencing, the HRM showed high sensitivity (0.96) and high specificity (0.98). In the three rabbit breeds, the allele C was the predominant allele. The polymorphic site showed high heterozygosity (He = 0.48) and high effective number of alleles (Ne = 1.91). The genetic diversity was reasonably informative (0.25

11.
Asian-Australas J Anim Sci ; 26(8): 1072-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25049887

RESUMO

The NLRP12 (NLR family, pyrin domain containing 12) serves as a suppressor factor in the inflammatory response and protects the host against inflammation-induced damage. In the present study, we aimed to study the polymorphisms of NLRP12 gene and its association with susceptibility to non-specific digestive disorder (NSDD) in rabbits. We re-sequenced the entire coding region of the rabbit NLRP12 gene and detected a total of 19 SNPs containing 14 synonymous and five non-synonymous variations. Among them, the coding SNP (c.1682A>G), which would carry a potential functional implication, was subsequently subjected to genotyping for case-control association study (272 cases and 267 controls). The results revealed that allele A was significantly protective against NSDD with an odds ratio value of 0.884 (95% confidence interval, 0.788 to 0.993; p = 0.038). We also experimentally induced NSDD in growing rabbits by feeding a fibre-deficient diet and subsequently investigated NLRP12 mRNA expression. The mRNA expression of NLRP12 in healthy status was significantly higher than that in severe NSDD (p = 0.0016). The highest expression was observed in individuals carrying the protective genotype AA (p = 0.0108). These results suggested that NLRP12 was significantly associated with the NSDD in rabbits. However, the precise molecular mechanism of NLRP12 involving in the development of rabbit NSDD requires further research.

12.
IEEE Trans Image Process ; 21(12): 4808-18, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22851260

RESUMO

Block truncation coding (BTC) is an efficient compression technique with extremely low computational complexity. However, the blocking and false contour effects are two major deficiencies in BTC which cause severe perceptual artifacts. The former scheme, error-diffused BTC (EDBTC), can significantly improve the above issues through the visual low-pass compensation on the bitmap, which thus widens its possible application market, yet the corresponding security issue may limit its value. In this paper, a method namely complementary hiding EDBTC is developed to cope the above issue. This paper is managed by firstly discussing when a single watermark is embedded, and then multiple watermarks are employed to test the limitation of the proposed scheme. Herein, an adaptive external bias factor is employed to control the watermark embedding, and this factor also affects the image quality and robustness simultaneously. Experimental results demonstrate that the proposed method only requires an extremely small external bias factor to carry watermarks, which enables a high capacity scenario without significantly damaging image quality.

13.
IEEE Trans Image Process ; 21(9): 4117-27, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22581134

RESUMO

In this paper, a halftoning-based watermarking method is presented. This method enables high pixel-depth watermark embedding, while maintaining high image quality. This technique is capable of embedding watermarks with pixel depths up to 3 bits without causing prominent degradation to the image quality. To achieve high image quality, the parallel oriented high-efficient direct binary search (DBS) halftoning is selected to be integrated with the proposed orientation modulation (OM) method. The OM method utilizes different halftone texture orientations to carry different watermark data. In the decoder, the least-mean-square-trained filters are applied for feature extraction from watermarked images in the frequency domain, and the naïve Bayes classifier is used to analyze the extracted features and ultimately to decode the watermark data. Experimental results show that the DBS-based OM encoding method maintains a high degree of image quality and realizes the processing efficiency and robustness to be adapted in printing applications.

14.
IEEE Trans Image Process ; 21(6): 3092-101, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22311863

RESUMO

In this paper, the impact of the lips for identity recognition is investigated. In fact, it is a challenging issue for identity recognition solely by the lips. In the first stage of the proposed system, a fast box filtering is proposed to generate a noise-free source with high processing efficiency. Afterward, five various mouth corners are detected through the proposed system, in which it is also able to resist shadow, beard, and rotation problems. For the feature extraction, two geometric ratios and ten parabolic-related parameters are adopted for further recognition through the support vector machine. Experimental results demonstrate that, when the number of subjects is fewer or equal to 29, the correct accept rate (CAR) is greater than 98%, and the false accept rate (FAR) is smaller than 0.066%. (CAR > 95.02%, FAR < 0.095% # Subjects ≤ 57). Moreover, the processing speed of the overall system achieves 34.43 frames per second, which meets the real-time requirement. Thus, the proposed system can be an effective candidate for facial biometrics applications when other facial organs are covered or when it is applied for an access control system.


Assuntos
Identificação Biométrica/métodos , Lábio/anatomia & histologia , Algoritmos , Bases de Dados Factuais , Humanos
15.
Cancer Lett ; 320(1): 40-7, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22266187

RESUMO

Frequent downregulation of microRNA-449a (miR-449a) was detected in 14 human bladder cancer tissues. The restoration of miR-449a inhibited cell growth and induced G1-phase arrest in T24 and 5637 human bladder cancer cells. CDK6 and CDC25a were downregulated after miR-449a treatment, resulting in the functional accumulation of the pocket proteins Rb and p130. The growth of T24 tumor xenografts was suppressed by exogenous miR-449a, and the nuclear proliferation antigen Ki-67 was downregulated in miR-449a-treated tumors. These results suggest a tumor-suppressive role for miR-449a in human bladder cancer.


Assuntos
Proteína Substrato Associada a Crk/genética , MicroRNAs/genética , Proteína do Retinoblastoma/genética , Neoplasias da Bexiga Urinária/genética , Idoso , Idoso de 80 Anos ou mais , Animais , Sequência de Bases , Processos de Crescimento Celular/genética , Linhagem Celular Tumoral , Proteína Substrato Associada a Crk/metabolismo , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Regulação para Baixo , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/administração & dosagem , MicroRNAs/biossíntese , Pessoa de Meia-Idade , Proteínas Mitocondriais , Dados de Sequência Molecular , Fosforilação , Proteína do Retinoblastoma/metabolismo , Transplante Heterólogo , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia , Fosfatases cdc25/antagonistas & inibidores
16.
IEEE Trans Image Process ; 20(10): 2837-47, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21926004

RESUMO

Former research on inverse halftoning most focus on developing a general-purpose method for all types of halftone patterns, such as error diffusion, ordered dithering, etc., while fail to consider the natural discrepancies among various halftoning methods. To achieve optimal image quality for each halftoning method, the classification of halftone images is highly demanded. This study employed the least mean-square filter for improving the robustness of the extracted features, and employed the naive Bayes classifier to verify all the extracted features for classification. Nine of the most well-known halftoning methods were involved for testing. The experimental results demonstrated that the classification performance can achieve a 100% accuracy rate, and the number of distinguishable halftoning methods is more than that of a former method established by Chang and Yu.

17.
IEEE Trans Image Process ; 20(10): 2800-12, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21435977

RESUMO

For image-based data hiding, it is difficult to achieve good image quality when high embedding capacity and 100% data extraction are also demanded. In this study, the proposed method, namely, overall minimal-error searching (OMES) is developed to meet the aforementioned requirements. Moreover, the concept of secret sharing is also adopted to distribute watermarks into multiple halftone images, and the embedded information can only be extracted when all of the marked images are gathered. The OMES modifies the halftone values at the same position of all host images with the trained substitution table (S-Table). The S-Table makes the original combination of these halftone values as another meaningful combination for embedding watermark, which is the key part in determining the image quality. Thus, an optimization procedure is proposed to achieve the optimized S-Table. Two different encoders, called error-diffused-based and least-mean-square-based approaches are also developed to cooperate with the proposed OMES to cope with high processing speed and high image quality applications, respectively. Finally, for resisting the issues caused by the print-and-scan attack, such as zooming, rotation, and dot gain effect, a compensation correction procedure is also proposed. As demonstrated in the experimental results, the proposed approach provides good image quality, and is able to guard against some frequent happened attacks in printing applications.

18.
IEEE Trans Image Process ; 20(4): 1077-84, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20959269

RESUMO

This study proposes a method which can generate high quality inverse halftone images from halftone images. This method can be employed prior to any signal processing over a halftone image or the inverse halftoning used in JBIG2. The proposed method utilizes the least-mean-square (LMS) algorithm to establish a relationship between the current processing position and its corresponding neighboring positions in each type of halftone image, including direct binary search, error diffusion, dot diffusion, and ordered dithering. After which, a referenced region called a support region (SR) is used to extract features. The SR can be obtained by relabeling the LMS-trained filters with the order of importance. Moreover, the probability of black pixel occurrence is considered as a feature in this work. According to this feature, the probabilities of all possible grayscale values at the current processing position can be obtained by the Bayesian theorem. Consequently, the final output at this position is the grayscale value with the highest probability. Experimental results show that the proposed method offers better visual quality than that of Mese-Vaidyanathan's and Chang et al's methods in terms of human-visual peak signal-to-noise ratio (HPSNR). In addition, the memory consumption is also superior to Mese-Vaidyanathan's method.


Assuntos
Algoritmos , Inteligência Artificial , Cor , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Teorema de Bayes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
IEEE Trans Image Process ; 19(8): 2056-69, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20236887

RESUMO

In this paper, a watermarking scheme, called majority-parity-guided error-diffused block truncation coding (MPG-EDBTC), is proposed to achieve high image quality and embedding capacity. EDBTC exploits the error diffusion to effectively reduce blocking effect and false contour which inherently exhibit in traditional BTC. In addition, the coding efficiency is significantly improved by replacing high and low means evaluation with extreme values substitution. The proposed MPG-EDBTC embeds a watermark simultaneously during compression by evaluating the parity value in a predefined parity-check region (PCR). As documented in the experimental results, the proposed scheme can provide good robustness, image quality, and processing efficiency. Finally, the proposed MPG-EDBTC is extended to embed multiple watermarks and achieves excellent image quality, robustness, and capacity. Nowadays, most multimedia is compressed before it is stored. It is more appropriate to embed information such as watermarks during compression. The proposed method has been proved to solve effectively the inherent problems in traditional BTC, and provide excellent performance in watermark embedding.


Assuntos
Algoritmos , Compressão de Dados/métodos , Interpretação de Imagem Assistida por Computador/métodos , Rotulagem de Produtos/métodos , Medidas de Segurança , Cor , Aumento da Imagem/métodos
20.
IEEE Trans Image Process ; 18(8): 1804-16, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19556199

RESUMO

Dot diffusion is an efficient approach which utilizes concepts of block-wise and parallel-oriented processing to generate halftones. However, the block-wise nature of processing reduces image quality much more significantly as compared to error diffusion. In this work, four types of filters with various sizes are employed in co-optimization procedures with class matrices of size 8 n 8 and 16 x 16 to improve the image quality. The optimal diffused weighting and area are determined through simulations. Many well-known halftoning methods, some of which includes direct binary search (DBS), error diffusion, ordered dithering, and prior dot diffusion methods, are also included for comparisons. Experimental results show that the proposed dot diffusion achieved quality close to some forms of error diffusion, and additionally, superior to the well-known Jarvis and Stucki error diffusion and Mese's dot diffusion. Moreover, the inherent parallel processing advantage of dot diffusion is preserved, allowing us to reap higher executing efficiency than both DBS and error diffusion.

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