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1.
Comput Biol Med ; 172: 108255, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38461696

RESUMO

Retinal fundus images serve as a non-invasive modality to obtain information pertaining to retinal vessels through fundus photography, thereby offering insights into cardiovascular and cerebrovascular diseases. Retinal arteriolar morphometry has emerged as the most convenient and fundamental clinical methodology in the realm of patient screening and diagnosis. Nevertheless, the analysis of retinal arterioles is challenging attributable to imaging noise, stochastic fuzzy characteristics, and blurred boundaries proximal to blood vessels. In response to these limitations, we introduce an innovative methodology, named PKSEA-Net, which aims to improve segmentation accuracy by enhancing the perception of edge information in retinal fundus images. PKSEA-Net employs the universal architecture PVT-v2 as the encoder, complemented by a novel decoder architecture consisting of an Edge-Aware Block (EAB) and a Pyramid Feature Fusion Module (PFFM). The EAB block incorporates prior knowledge for supervision and multi-query for multi-task learning, with supervision information derived from an enhanced Full Width at Half Maximum (FWHM) algorithm and gradient map. Moreover, PFFM efficiently integrates multi-scale features through a novel attention fusion method. Additionally, we have collected a Retinal Cross-Sectional Vessel (RCSV) dataset derived from approximately 200 patients in Quzhou People's Hospital to serve as the benchmark dataset. Comparative evaluations with several state-of-the-art (SOTA) networks confirm that PKSEA-Net achieves exceptional experimental performance, thereby establishing its status as a SOTA approach for precise boundary delineation and retinal vessel segmentation.


Assuntos
Aprendizagem , Vasos Retinianos , Humanos , Arteríolas/diagnóstico por imagem , Estudos Transversais , Vasos Retinianos/diagnóstico por imagem , Algoritmos , Processamento de Imagem Assistida por Computador
2.
BMC Pediatr ; 15: 77, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26174701

RESUMO

BACKGROUND: Fragile X syndrome is the most common genetic disorder of intellectual developmental disorder/mental retardation (IDD/MR). The prevalence of FXS in a Chinese IDD children seeking diagnosis/treatment in mainland China is unknown. METHODS: Patients with unknown moderate to severe IDD were recruited from two children's hospitals. Informed consent was obtained from the children's parents. The size of the CGG repeat was identified using a commercial TP-PCR assay. The influence of AGG interruptions on the CGG expansion during maternal transmission was analyzed in 24 mother-son pairs (10 pairs with 1 AGG and 14 pairs with 2 AGGs). RESULTS: 553 unrelated patients between six months and eighteen years of age were recruited. Specimens from 540 patients (male:female = 5.2:1) produced high-quality TP-PCR data, resulting in the determination of the FMR1 CGG repeat number for each. The most common repeat numbers were 29 and 30, and the most frequent interruption pattern was 2 or 3 AGGs. Five full mutations were identified (1 familial and 4 sporadic IDD patients), and size mosaicism was apparent in 4 of these FXS patients (4/5 = 80%). The overall yield of FXS in the IDD cohort was 0.93% (5/540). Neither the mean size of CGG expansion (0.20 vs. 0.79, p > 0.05) nor the frequency of CGG expansion (2/10 vs. 9/14, p > 0.05) was significantly different between the 1 and 2 AGG groups following maternal transmission. CONCLUSIONS: The FMR1 TP-PCR assay generates reliable and sensitive results across a large number of patient specimens, and is suitable for clinical genetic diagnosis. Using this assay, the prevalence of FXS was 0.93% in Chinese children with unknown IDD.


Assuntos
Síndrome do Cromossomo X Frágil/diagnóstico , Síndrome do Cromossomo X Frágil/epidemiologia , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Feminino , Proteína do X Frágil da Deficiência Intelectual/genética , Genótipo , Humanos , Lactente , Deficiência Intelectual/etiologia , Masculino , Linhagem , Reação em Cadeia da Polimerase , Prevalência
3.
Ophthalmic Genet ; 36(1): 64-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23834559

RESUMO

BACKGROUND: Retinitis pigmentosa (RP) is a group of inherited retinal dystrophies characterized by night blindness, progressive peripheral visual field loss, and loss of central vision. Fifty-three RP pathogenic genes are responsible for RP. Pre-mRNA processing factor 31(PRPF31) gene is the third most common cause of autosomal dominant retinitis pigmentosa (adRP), and so far more than 40 mutations in PRPF31 have been detected. PURPOSE: To identify the underlying genetic defect in a five-generation Chinese family affected with adRP and to study the genotype-phenotype relationship of this family. METHODS: Detailed clinical investigations were undertaken and peripheral blood samples were collected from 25 individuals. Microsatellite (STR) markers tightly linked to genes known to be responsible for adRP were selected for linkage analysis. Exons and adjacent splice junctions of the candidate gene were amplified and sequenced. RESULTS: This adRP family exhibited an incomplete penetrance of the RP phenotype. In affected individuals, age of disease onset was from infancy to 4 years of age. Typical RP features were associated with this mutation. Linkage analysis identified a maximum two-point LOD score of 3.20 with D19S418, which is close to PRPF31. A mutation PRPF31: (c.358-359 del AA) was identified by linkage analysis. CONCLUSIONS: A PRPF31 mutation was identified to be responsible for adRP in a large Chinese family. Our findings expand the mutation spectrum of RP in the Chinese population.


Assuntos
Povo Asiático/genética , Proteínas do Olho/genética , Genes Dominantes/genética , Mutação , Retinose Pigmentar/genética , Adulto , Idoso , China/epidemiologia , Análise Mutacional de DNA , Eletrorretinografia , Éxons/genética , Feminino , Angiofluoresceinografia , Estudos de Associação Genética , Ligação Genética , Humanos , Escore Lod , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Linhagem , Reação em Cadeia da Polimerase , Retinose Pigmentar/diagnóstico , Tomografia de Coerência Óptica , Adulto Jovem
4.
Ultramicroscopy ; 108(6): 579-88, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18036739

RESUMO

It is a major issue to improve the thermo-mechanical sensitivity of uncooled optomechanical focal plane arrays (FPAs) for infrared imaging. This work presents an optimized multi-fold interval metallized leg (IML) configuration to increase the thermo-mechanical sensitivity of an uncooled optomechanical bi-material micro-cantilever array. The inclination angle changes of the cantilever elements are measured in the IR imaging system using an optical readout with a knife-edge filtering operation in the spectrum plane. The multi-fold IML configuration consists of alternately connected unmetallized and metallized legs. With the optimized fold number, the thermo-mechanical sensitivity of a micro-cantilever array can be amplified to two times of one-fold IML for a 120 microm x 120 microm element with 1 microm thick SiNx/0.2 microm thick Au films. Room temperature objects are imaged with the fabricated FPA containing 160 x 160 elements and a 12-bit CCD. Further modeling analysis shows that the experimental results are well accordant with the theoretical calculation. An important practical feature of the implemented approach is its straightforward fabrication for a large FPA, without growing complexity and cost.

5.
Ultramicroscopy ; 107(8): 610-6, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17317012

RESUMO

In this study, we present an uncooled infrared imaging detector using knife-edge filter optical readout method. The tilt angle change of each cantilever in a focal plane array (FPA) can be simultaneously detected with a resolution of 10(-5) degrees. A deformation magnifying substrate-free microcantilever unit is specially designed. The multi-fold legs of microcantilever are interval metal coated to form a thermal deformation magnifying structure. Thermal and thermomechanical performance of this microcantilever unit are modeled and analyzed. An FPA with 100 x 100 pixels is fabricated and thermal images of human body are obtained by this detector.


Assuntos
Raios Infravermelhos , Microscopia/métodos , Desenho de Equipamento , Humanos , Mecânica , Microscopia/instrumentação , Óptica e Fotônica/instrumentação , Termodinâmica , Termografia/instrumentação , Termografia/métodos
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