52 research outputs found

    Multi-Method Analysis of MRI Images in Early Diagnostics of Alzheimer's Disease

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    The role of structural brain magnetic resonance imaging (MRI) is becoming more and more emphasized in the early diagnostics of Alzheimer's disease (AD). This study aimed to assess the improvement in classification accuracy that can be achieved by combining features from different structural MRI analysis techniques. Automatically estimated MR features used are hippocampal volume, tensor-based morphometry, cortical thickness and a novel technique based on manifold learning. Baseline MRIs acquired from all 834 subjects (231 healthy controls (HC), 238 stable mild cognitive impairment (S-MCI), 167 MCI to AD progressors (P-MCI), 198 AD) from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database were used for evaluation. We compared the classification accuracy achieved with linear discriminant analysis (LDA) and support vector machines (SVM). The best results achieved with individual features are 90% sensitivity and 84% specificity (HC/AD classification), 64%/66% (S-MCI/P-MCI) and 82%/76% (HC/P-MCI) with the LDA classifier. The combination of all features improved these results to 93% sensitivity and 85% specificity (HC/AD), 67%/69% (S-MCI/P-MCI) and 86%/82% (HC/P-MCI). Compared with previously published results in the ADNI database using individual MR-based features, the presented results show that a comprehensive analysis of MRI images combining multiple features improves classification accuracy and predictive power in detecting early AD. The most stable and reliable classification was achieved when combining all available features

    A deletion of IDUA exon 10 in a family of Golden Retriever dogs with an attenuated form of mucopolysaccharidosis type 1

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    Background: Mucopolysaccharidosis type I (MPS‐I) is a lysosomal storage disorder caused by a deficiency of the enzyme α‐l‐iduronidase, leading to accumulation of undegraded dermatan and heparan sulfates in the cells and secondary multiorgan dysfunction. In humans, depending upon the nature of the underlying mutation(s) in the IDUA gene, the condition presents with a spectrum of clinical severity. Objectives: To characterize the clinical and biochemical phenotypes, and the genotype of a family of Golden Retriever dogs. Animals: Two affected siblings and 11 related dogs. Methods: Family study. Urine metabolic screening and leucocyte lysosomal enzyme activity assays were performed for biochemical characterization. Whole genome sequencing was used to identify the causal mutation. Results: The clinical signs shown by the proband resemble the human attenuated form of the disease, with a dysmorphic appearance, musculoskeletal, ocular and cardiac defects, and survival to adulthood. Urinary metabolic studies identified high levels of dermatan sulfate, heparan sulfate, and heparin. Lysosomal enzyme activities demonstrated deficiency in α‐l‐iduronidase activity in leucocytes. Genome sequencing revealed a novel homozygous deletion of 287 bp resulting in full deletion of exon 10 of the IDUA gene (NC_006585.3(NM_001313883.1):c.1400‐76_1521+89del). Treatment with pentosan polyphosphate improved the clinical signs until euthanasia at 4.5 years. Conclusion and Clinical Importance: Analysis of the genotype/phenotype correlation in this dog family suggests that dogs with MPS‐I could have a less severe phenotype than humans, even in the presence of severe mutations. Treatment with pentosan polyphosphate should be considered in dogs with MPS‐I

    Evaluation and Outcomes of Women with a Breast Lump and a Normal Mammogram Result

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    BACKGROUND: Many women experience a breast lump. Clinical guidelines suggest that a normal mammogram result alone is not adequate to exclude a diagnosis of cancer. OBJECTIVE: To examine the characteristics of women with a breast lump and a normal mammogram that were associated with receiving further evaluation, and to examine cancer outcomes. DESIGN: Observational cohort. PARTICIPANTS: Women aged 35 to 70 years who participated in a population-based mammography registry and who did not have a history of breast cancer noted at the time of their mammogram that they had a breast lump, and had a “normal” (Breast Imaging Reporting and Data System 1 or 2) mammogram result (n=771). MEASUREMENTS: Telephone survey performed 6 months after the mammogram to ascertain information about evaluation. Cancer outcomes within 12 months of the index mammogram were confirmed through linkage with a cancer registry. RESULTS: Only 56.9% of women reported receiving an adequate evaluation for their breast lump, including a subsequent clinical breast exam, a visit to a breast specialist, an ultrasound, a biopsy, or aspiration. Latinas were less likely than white women to have received adequate evaluation, as were obese women compared with normal-weight women, and uninsured women compared with women with insurance. Among women with at least 12 months of follow-up, 1.4% were diagnosed with cancer. CONCLUSIONS: Many women do not receive adequate evaluation for a recent breast lump. Interventions should be designed to improve the follow-up of women with this common clinical problem
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