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1.
Sci Data ; 7(1): 409, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33219237

RESUMO

Automated detection of exudates from fundus images plays an important role in diabetic retinopathy (DR) screening and evaluation, for which supervised or semi-supervised learning methods are typically preferred. However, a potential limitation of supervised and semi-supervised learning based detection algorithms is that they depend substantially on the sample size of training data and the quality of annotations, which is the fundamental motivation of this work. In this study, we construct a dataset containing 1219 fundus images (from DR patients and healthy controls) with annotations of exudate lesions. In addition to exudate annotations, we also provide four additional labels for each image: left-versus-right eye label, DR grade (severity scale) from three different grading protocols, the bounding box of the optic disc (OD), and fovea location. This dataset provides a great opportunity to analyze the accuracy and reliability of different exudate detection, OD detection, fovea localization, and DR classification algorithms. Moreover, it will facilitate the development of such algorithms in the realm of supervised and semi-supervised learning.

2.
JMIR Med Inform ; 8(11): e23472, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33139242

RESUMO

BACKGROUND: Retinal imaging has been applied for detecting eye diseases and cardiovascular risks using deep learning-based methods. Furthermore, retinal microvascular and structural changes were found in renal function impairments. However, a deep learning-based method using retinal images for detecting early renal function impairment has not yet been well studied. OBJECTIVE: This study aimed to develop and evaluate a deep learning model for detecting early renal function impairment using retinal fundus images. METHODS: This retrospective study enrolled patients who underwent renal function tests with color fundus images captured at any time between January 1, 2001, and August 31, 2019. A deep learning model was constructed to detect impaired renal function from the images. Early renal function impairment was defined as estimated glomerular filtration rate <90 mL/min/1.73 m2. Model performance was evaluated with respect to the receiver operating characteristic curve and area under the curve (AUC). RESULTS: In total, 25,706 retinal fundus images were obtained from 6212 patients for the study period. The images were divided at an 8:1:1 ratio. The training, validation, and testing data sets respectively contained 20,787, 2189, and 2730 images from 4970, 621, and 621 patients. There were 10,686 and 15,020 images determined to indicate normal and impaired renal function, respectively. The AUC of the model was 0.81 in the overall population. In subgroups stratified by serum hemoglobin A1c (HbA1c) level, the AUCs were 0.81, 0.84, 0.85, and 0.87 for the HbA1c levels of ≤6.5%, >6.5%, >7.5%, and >10%, respectively. CONCLUSIONS: The deep learning model in this study enables the detection of early renal function impairment using retinal fundus images. The model was more accurate for patients with elevated serum HbA1c levels.

3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1976-1979, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018390

RESUMO

In this paper, we proposed and validated a probability distribution guided network for segmenting optic disc (OD) and optic cup (OC) from fundus images. Uncertainty is inevitable in deep learning, as induced by different sensors, insufficient samples, and inaccurate labeling. Since the input data and the corresponding ground truth label may be inaccurate, they may actually follow some potential distribution. In this study, a variational autoencoder (VAE) based network was proposed to estimate the joint distribution of the input image and the corresponding segmentation (both the ground truth segmentation and the predicted segmentation), making the segmentation network learn not only pixel-wise information but also semantic probability distribution. Moreover, we designed a building block, namely the Dilated Inception Block (DIB), for a better generalization of the model and a more effective extraction of multi-scale features. The proposed method was compared to several existing state-of-the-art methods. Superior segmentation performance has been observed over two datasets (ORIGA and REFUGE), with the mean Dice overlap coefficients being 96.57% and 95.81% for OD and 88.46% and 88.91% for OC.


Assuntos
Glaucoma , Disco Óptico , Animais , Fundo de Olho , Fundo Gástrico , Disco Óptico/diagnóstico por imagem , Probabilidade
4.
BMC Pediatr ; 19(1): 485, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822277

RESUMO

BACKGROUND: This study was performed to identify risk factors associated with recurrence of hepatoblastoma. METHODS: A retrospective study was conducted on 56 patients with hepatoblastoma from 2012 to 2015 in Beijing Children's Hospital. Pretreatment extension stage (PRETEXT), serum alpha fetoprotein (AFP) value, change trend of tumors after treatment and some other clinical characteristics were collected and analyzed. The comparison of independent variables that were not distributed normally was performed with the log-rank test. RESULTS: Twenty-eight patients with tumour recurrence and 28 patients without recurrence were included in this study, and the median age at presentation was 46.5 (26, 71.5) months. There was a significant difference in the 3-year recurrence-free survival (RFS) probability between patients aged over 54 months and those younger than 54 months (p = 0.007). After neoadjuvant chemotherapy, the chance of recurrence in partial response (PR) patients was significantly lower than that in stable disease (SD) patients (p = 0.004). The 3-year RFS rate of patients with a reduction in AFP of more than 60% after neoadjuvant chemotherapy was significantly higher than that of patients with a reduction of less than 60% (p = 0.005). The postoperative follow-up revealed that patients whose postoperative AFP fell to normal levels within 6 months of the start of treatment had a 3-year RFS rate of 68.6%, which is higher than that of patients whose AFP fell below the normal range after 6 months (p = 0.0005). Finally, the multivariate analysis by Cox regression showed that AFP decreased by less than 60% and tumour size decreased by less than 50% after neoadjuvant chemotherapy were significant independent prognostic risk factors for the 3-year RFS rate. The other clinical features were not significantly associated with tumour recurrence in this study. CONCLUSIONS: Through this study, we concluded that the prognosis of childhood HB is related to the age at presentation and the response of chemotherapy. The results of the multivariate analysis showed that AFP decreased by less than 60% and tumour size decreased by less than 50% after neoadjuvant chemotherapy were significant independent prognostic risk factors. These findings can be helpful to evaluate therapeutic effects and predict prognosis.


Assuntos
Hepatoblastoma/epidemiologia , Neoplasias Hepáticas/epidemiologia , Recidiva Local de Neoplasia/epidemiologia , Pré-Escolar , Feminino , Hepatoblastoma/patologia , Hepatoblastoma/terapia , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Masculino , Estudos Retrospectivos , Fatores de Risco
5.
Pediatr Surg Int ; 35(11): 1231-1238, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31338582

RESUMO

BACKGROUND: Pancreatoblastoma is a very rare malignant pancreatic tumor in children. Pancreatoblastoma is the most common pancreatic tumor in children less than 10 years of age, accounting for 25% of the pancreatic neoplasm. There were only a few published literatures about the standardized diagnostic and management protocol for PB in the last decade. OBJECTIVE: To summarize our experience in the management of pancreatoblastoma in children and adolescents with emphasis on the presentation, diagnosis, treatment, and outcomes. A management strategy will also be discussed. METHODS: This was a retrospective case-series study of all pancreatoblastoma in patients < 18 years of age who were treated at Beijing children's hospital (BCH) from January 2002-January 2015. The diagnoses of PB were confirmed by histopathology analysis of the resected specimen. The variables being analyzed included patient demographics, age at diagnosis, clinical presentation, tumor size, metastasis if present, tumor markers (AFP), type of surgery, length of follow-up, and outcome. The assessment of the tumor location, size, extent of the tumor, and distant metastasis was made by ultrasound (US), computed tomography (CT), and/or magnetic resonance imaging (MRI). RESULT: 21 patients with pancreatoblastoma were diagnosed at a median age of 4 years, 7 girls, and 14 boys. The diagnosis of pancreatoblastoma was identified by the histology examination. The most common syndrome was abdominal mass (n = 11), followed by abdominal pain (N = 10), elevated serum AFP levels were noted in almost all cases (17/18), 17 patients with disease initially unresectable on diagnosis accepted neo-adjuvant chemotherapy consisting of CDV, OPEC, PLADO, IEV, and AVCP. All patients underwent surgery, including pancreaticoduodenectomy (Whipple's procedure), the Pylorus-preserving pancreaticoduodenectomy (traverse-Longmire procedure), Spleen-preserving distal pancreatectomy, and distal pancreatectomy with en bloc splenectomy, Roux-en-Y end-to-end pancreatojejunostomy. In all, 13 children were disease free with a median follow-up of 53 months (range 11-156 months). CONCLUSIONS: The pancreatoblastoma in children and adolescents is a malignant tumor. Complete resection combined with chemotherapy is associated with long-term survival. For the unresectable tumor at diagnosis, preoperative chemotherapy was recommended to reduce tumor volume. AFP is critical for diagnosis and monitoring the disease as a tumors marker.


Assuntos
Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/terapia , Dor Abdominal/etiologia , Quimioterapia Adjuvante , Criança , Pré-Escolar , China/epidemiologia , Intervalo Livre de Doença , Feminino , Hospitais Pediátricos , Humanos , Masculino , Pancreatectomia , Neoplasias Pancreáticas/mortalidade , Pancreaticoduodenectomia , Pancreaticojejunostomia , Estudos Retrospectivos , alfa-Fetoproteínas/análise
6.
Arch Dermatol Res ; 310(7): 561-566, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29931443

RESUMO

Keloids are skin fibroproliferative tumors characterized by locally invasive growth of fibroblasts and excessive collagen deposition. The objective of this study is to investigate the molecular basis of the keloid scar by studying the mutation of related genes. We performed gene screening of mechanoreceptors by quantitative polymerase chain reaction (qPCR), Sanger sequencing to detect the CXCR1gene mutation, and immuno-histochemistry to determine CXCR1 protein expression. Among the genes encoding mechanoreceptors, the expression of CXCR1 mRNA was significantly higher in keloid scar tissues than in the surrounding tissues of normal controls (P < 0.05). Sequencing analysis identified a novel missense mutation, c.574G > A (p.Gly192Glu). Immunohistochemistry showed heightened protein expression of CXCR1 in keloid scars as compared to controls. Our findings indicate that CXCR1 gene mutation and altered protein expression are associated with keloid scar development. Identification of the CXCR1 gene mutation might provide insights into the molecular mechanism underlying keloid scar and underscores the potential importance of mechanoreceptors in keloid scar pathogenesis.


Assuntos
Cicatriz Hipertrófica/genética , Queloide/genética , Mutação de Sentido Incorreto/genética , RNA Mensageiro/genética , Receptores de Interleucina-8A/genética , Pele/patologia , China , Cicatriz Hipertrófica/metabolismo , Feminino , Testes Genéticos , Humanos , Imuno-Histoquímica , Queloide/metabolismo , Masculino , Mecanorreceptores/metabolismo , Receptores de Interleucina-8A/metabolismo , Estudos Retrospectivos , Pele/metabolismo , Regulação para Cima
7.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 33(5): 645-8, 2016 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-27577213

RESUMO

OBJECTIVE: To identify potential mutations of the FLG gene in two Chinese families affected with ichthyosis vulgaris. METHODS: All coding exons and exon-intron boundary of the FLG gene were amplified by polymerase chain reaction (PCR) and analyzed by direct sequencing. The results were compared with those of 100 unrelated healthy controls. RESULTS: Two novel missense mutations, c.1360A>G (p.T454A) and c.10363G>T (p.D3455Y), were detected in all affected individuals from family 1 and family 2 respectively but none of the controls. CONCLUSION: The c.1360A>G (p.T454A) and c.10363G>T (p.D3455Y) of the FLG gene may lead to alteration of the structure and function of the FLG protein and cause ichthyosis vulgaris in the two families.


Assuntos
Predisposição Genética para Doença/genética , Ictiose Vulgar/genética , Proteínas de Filamentos Intermediários/genética , Mutação de Sentido Incorreto , Grupo com Ancestrais do Continente Asiático/genética , Sequência de Bases , China , Análise Mutacional de DNA , Éxons/genética , Saúde da Família , Feminino , Predisposição Genética para Doença/etnologia , Humanos , Ictiose Vulgar/etnologia , Íntrons/genética , Masculino , Linhagem
8.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 31(3): 294-7, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-24928005

RESUMO

OBJECTIVE: To investigate STK11 gene mutation in a pedigree with Peutz-Jeghers syndrome (PJS). METHODS: A pedigree of PJS was investigated. DNA was extracted from peripheral blood samples from affected and unaffected members of the pedigree and 100 unrelated healthy controls. PCR was performed to amplify all of the 9 coding exons of STK11 gene. PCR products were directly sequenced to detect mutation. RESULTS: A missense mutation p.F354L (c.1062C>G) in exon 8 of the STK11 gene has been identified in all patients with PJS, but was not found in normal individuals from the pedigree and 100 unrelated controls. CONCLUSION: A missense mutation p.F354L of STK11 gene probably underlies the disease in this pedigree.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Síndrome de Peutz-Jeghers/enzimologia , Síndrome de Peutz-Jeghers/genética , Proteínas Serina-Treonina Quinases/genética , Adulto , Sequência de Bases , Análise Mutacional de DNA , Éxons , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Síndrome de Peutz-Jeghers/diagnóstico
9.
Nat Commun ; 5: 2870, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24399259

RESUMO

Severe acne is a chronic inflammatory skin disorder characterized by widespread inflammatory lesions including nodules, cysts and potential scarring. Here we perform the first genome-wide association study of severe acne in a Chinese Han population comprising 1,056 cases and 1,056 controls using the Illumina HumanOmniZhongHua-8 BeadChip. In an independent cohort of 1,860 cases and 3,660 controls of Chinese Han, we replicate 101 SNPs of which 3 showed consistent association. We identify two new susceptibility loci at 11p11.2 (DDB2, rs747650, P(combined)=4.41 × 10⁻9 and rs1060573, P(combined)=1.28 × 10⁻8) and 1q24.2 (SELL, rs7531806, P(combined)=1.20 × 10⁻8) that are involved in androgen metabolism, inflammation processes and scar formation in severe acne. These results point to new genetic susceptibility factors and suggest several new biological pathways related to severe acne.


Assuntos
Acne Vulgar/genética , Proteínas de Ligação a DNA/genética , Adolescente , Adulto , Grupo com Ancestrais do Continente Asiático , Estudos de Coortes , Feminino , Predisposição Genética para Doença , Humanos , Selectina L , Masculino , Polimorfismo de Nucleotídeo Único , Adulto Jovem
12.
Electrophoresis ; 30(22): 3964-70, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19885883

RESUMO

Functionalized multiwalled carbon nanotubes (f-MWCNTs) can serve as the pseudostationary phase (PSP) for the capillary EKC separation of non-steroidal anti-inflammatory drugs (NSAIDs). To increase their hydrophilicity, we treated MWCNTs, with a sonochemical process in a concentrated nitric/sulfuric acid mixture. The oxidized MWCNTs were then characterized by FT-IR, transmission electron microscopy, and X-ray photoelectron spectroscopy. We evaluated the potential of the PSP and the effects of buffer composition, pH, addition of organic modifier, and injection temperature on the NSAID separation. The PSP created a network structure of pi-pi interactions, hydrophobic forces, hydrogen bonding, and electrostatic interactions to separate NSAIDs, providing a different separation mode from SDS micelles. We achieved complete separation of six NSAIDs using a mixture of a borate buffer (75 mM, pH 10) with methanol (5%, v/v) containing 0.02 mg/mL f-MWCNTs, an applied voltage of +12 kV and detection at 214 nm. Better precision was obtained with a low injection temperature. The method was also satisfactorily applied to the analysis of NSAIDs spiked into a urine sample.


Assuntos
Anti-Inflamatórios não Esteroides/isolamento & purificação , Cromatografia Capilar Eletrocinética Micelar/métodos , Nanotubos de Carbono/química , Anti-Inflamatórios não Esteroides/urina , Humanos , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Oxirredução , Reprodutibilidade dos Testes , Solventes/farmacologia , Eletricidade Estática , Temperatura
13.
Exp Dermatol ; 15(12): 966-70, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17083363

RESUMO

Brooke-Spiegler syndrome (BSS) is an autosomal dominant disease characterized by cylindromas, trichoepitheliomas and occasionally spiradenomas. The disease gene was mapped to 16q12-13, and mutations in the CYLD gene were identified in families with BSS. In the present report, we describe a large consanguineous Chinese family with BSS showing an intra-family phenotypic variability. Clinically, some affected individuals only revealed discrete small skin-coloured tumors whereas the proband showed an expansion of multiple large tumors on the back of nose and numerous dome-shaped papules on her scalp. Histologically, both trichoepitheliomas and cylindromas were found in the affected individuals. By sequence analysis, we identified a recurrent mutation 2272C>T (R758X) of the CYLD gene in the affected individuals of this family, which was previously identified in other ethnic families with familial cylindromatosis. Our result provided additional information for phenotype-genotype correlation in BSS.


Assuntos
Carcinoma Adenoide Cístico/genética , Carcinoma de Apêndice Cutâneo/genética , Códon sem Sentido , Neoplasias Cutâneas/genética , Proteínas Supressoras de Tumor/genética , Adulto , Carcinoma Adenoide Cístico/patologia , Carcinoma de Apêndice Cutâneo/patologia , China , Análise Mutacional de DNA , Enzima Desubiquitinante CYLD , Saúde da Família , Feminino , Humanos , Masculino , Neoplasias Primárias Múltiplas/genética , Neoplasias Primárias Múltiplas/patologia , Linhagem , Fenótipo , Neoplasias Cutâneas/patologia
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