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1.
Ultrasound Med Biol ; 49(3): 761-772, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463005

RESUMO

Early stages of diabetic kidney disease (DKD) are difficult to diagnose in patients with type 2 diabetes. This work was aimed at identifying contrast-enhanced ultrasound (CEUS) perfusion parameters, a microcirculatory biomarker indicative of early DKD progression. CEUS kidney flash-replenishment data were acquired in control, insulin resistant and diabetic vervet monkeys (N = 16). By use of a mono-exponential model, time-intensity curve parameters related to blood volume (A), velocity (ß) and flow rate (perfusion index [PI]) were extracted from 10 concentric kidney layers to study spatial perfusion patterns that could serve as strong indicators of disease. Mean squared error (MSE) was used to assess model performance. Features calculated from the perfusion parameters were inputs for the linear regression models to determine which features could distinguish between cohorts. The mono-exponential model performed well, with average MSEs (±standard deviation) of 0.0254 (±0.0210), 0.0321 (±0.0242) and 0.0287 (±0.0130) for the control, insulin resistant and diabetic cohorts, respectively. Perfusion index features, with blood pressure, were the best classifiers between cohorts (p < 0.05). CEUS has the potential to detect early microvascular changes, providing insight into disease-related structural changes in the kidney. The sensitivity of this technique should be explored further by assessing various stages of DKD.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Insulinas , Animais , Chlorocebus aethiops , Meios de Contraste , Microcirculação , Rim/irrigação sanguínea , Ultrassonografia/métodos , Nefropatias Diabéticas/diagnóstico por imagem , Perfusão
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 2437-2443, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891773

RESUMO

Among males, prostate cancer (Pca) is the cancer type with the highest prevalence and the second leading cause of cancer deaths. The current screening methods for prostate cancer lack effectiveness such as prostate-specific antigen (PSA) and digital rectal exam (DRE). Machine learning models have been used to predict Pca progression, Gleason score, and laterality. In this research paper, we have employed novel Machine learning techniques such as Bayesian approach, Support vector machines (SVM), Decision Trees, Logistic Regression, K-Nearest Neighbors, Random Forest and AdaBoost for detecting malignant prostate cancers from benign ones. Moreover, different feature extracting strategies are proposed to improve the detection performance and identify potential genomic biomarkers. The results show the Lasso feature set yielded high performance from the models with SVM achieving exemplary classification accuracy of 97%. The Lasso and SVM combination reported many significant biomarker genes and gene mutations including but not restricted to CA2320112, CA2328529, and CA2436168.


Assuntos
Neoplasias da Próstata , Teorema de Bayes , Humanos , Masculino , Mutação , Gradação de Tumores , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética , Máquina de Vetores de Suporte
3.
Biomed Res Int ; 2016: 4628592, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27747230

RESUMO

Internally symmetric proteins are proteins that have a symmetrical structure in their monomeric single-chain form. Around 10-15% of the protein domains can be regarded as having some sort of internal symmetry. In this regard, we previously published SymD (symmetry detection), an algorithm that determines whether a given protein structure has internal symmetry by attempting to align the protein to its own copy after the copy is circularly permuted by all possible numbers of residues. SymD has proven to be a useful algorithm to detect symmetry. In this paper, we present a new parallelized algorithm called Parallel-SymD for detecting symmetry of proteins on clusters of computers. The achieved speedup of the new Parallel-SymD algorithm scales well with the number of computing processors. Scaling is better for proteins with a larger number of residues. For a protein of 509 residues, a speedup of 63 was achieved on a parallel system with 100 processors.


Assuntos
Conformação Proteica , Domínios Proteicos/genética , Proteínas/química , Algoritmos , Sequência de Aminoácidos/genética , Biologia Computacional , Proteínas/genética
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