Enhanced classification of left ventricular hypertrophy in cardiac patients using extended Siamese CNN.

Objective.Left ventricular hypertrophy (LVH) is the thickening of the left ventricle wall of the heart. The objective of this study is to develop a novel approach for the accurate assessment of LVH) severity, addressing the limitations of traditional manual grading systems.Approach.We propose the Multi-purpose Siamese Weighted Euclidean Distance Model (MSWED), which utilizes convolutional Siamese neural networks and zero-shot/few-shot learning techniques. Unlike traditional methods, our model introduces a cutoff distance-based approach for zero-shot learning, enhancing accuracy. We also incorporate a weighted Euclidean distance targeting informative regions within echocardiograms.Main results.We collected comprehensive datasets labeled by experienced echocardiographers, including Normal heart and various levels of LVH severity. Our model outperforms existing techniques, demonstrating significant precision enhancement, with improvements of up to 13% for zero-shot and few-shot learning approaches.Significance.Accurate assessment of LVH severity is crucial for clinical prognosis and treatment decisions. Our proposed MSWED model offers a more reliable and efficient solution compared to traditional grading systems, reducing subjectivity and errors while providing enhanced precision in severity classification.

A data-efficient zero-shot and few-shot Siamese approach for automated diagnosis of left ventricular hypertrophy.

Left ventricular hypertrophy (LVH) is a life-threatening condition in which the muscle of the left ventricle thickens and enlarges. Echocardiography is a test performed by cardiologists and echocardiographers to diagnose this condition. The manual interpretation of echocardiography tests is time-consuming and prone to errors. To address this issue, we have developed an automated LVH diagnosis technique using deep learning. However, the availability of medical data is a significant challenge due to varying industry standards, privacy laws, and legal constraints. To overcome this challenge, we have proposed a data-efficient technique for automated LVH classification using echocardiography. Firstly, we collected our own dataset of normal and LVH echocardiograms from 70 patients in collaboration with a clinical facility. Secondly, we introduced novel zero-shot and few-shot algorithms based on a modified Siamese network to classify LVH and normal images. Unlike traditional zero-shot learning approaches, our proposed method does not require text vectors, and classification is based on a cutoff distance. Our model demonstrates superior performance compared to state-of-the-art techniques, achieving up to 8% precision improvement for zero-shot learning and up to 11% precision improvement for few-shot learning approaches. Additionally, we assessed the inter-observer and intra-observer reliability scores of our proposed approach against two expert echocardiographers. The results revealed that our approach achieved better inter-observer and intra-observer reliability scores compared to the experts.

Cardiac phase detection in echocardiography using convolutional neural networks.

Echocardiography is a commonly used and cost-effective test to assess heart conditions. During the test, cardiologists and technicians observe two cardiac phases-end-systolic (ES) and end-diastolic (ED)-which are critical for calculating heart chamber size and ejection fraction. However, non-essential frames called Non-ESED frames may appear between these phases. Currently, technicians or cardiologists manually detect these phases, which is time-consuming and prone to errors. To address this, an automated and efficient technique is needed to accurately detect cardiac phases and minimize diagnostic errors. In this paper, we propose a deep learning model called DeepPhase to assist cardiology personnel. Our convolutional neural network (CNN) learns from echocardiography images to identify the ES, ED, and Non-ESED phases without the need for left ventricle segmentation or electrocardiograms. We evaluate our model on three echocardiography image datasets, including the CAMUS dataset, the EchoNet Dynamic dataset, and a new dataset we collected from a cardiac hospital (CardiacPhase). Our model outperforms existing techniques, achieving 0.96 and 0.82 area under the curve (AUC) on the CAMUS and CardiacPhase datasets, respectively. We also propose a novel cropping technique to enhance the model's performance and ensure its relevance to real-world scenarios for ES, ED, and Non ES-ED classification.

Upregulation and inhibition of the nuclear translocation of Oct4 during multistep gastric carcinogenesis.

Gastric cancer is the fourth most commonly diagnosed malignancy and the second leading cause of cancer-related mortality worldwide. Recent research suggests that tissue stem cells and the self renewal transcription factor, octamer-binding transcription factor 4 (Oct4), could be involved in the development of certain tumors. The aim of this study was to investigate the expression pattern of Oct4 in normal human stomach and during multistep gastric carcinogenesis. Pyloric antral mucosal tissues were obtained from consenting individuals undergoing endoscopy (due to upper gastrointestinal symptoms) and gastrectomy (due to pyloric antral adenocarcinoma). Some tissue samples were processed to assemble an array of tissue sections representing multistep carcinogenesis and probed using anti-Oct4 antibodies and lectins specific for α-L-fucose or N-acetyl-D-glucosamine. Some tissue samples were processed for subcellular fractionation and western blot analysis using the same antibodies. The results revealed that Oct4-expressing cells were found in the proliferative cell compartment of the pit-gland units of microscopically normal gastric mucosal biopsies. Mucosal tissues with evidence of severe gastritis, metaplastic/dysplastic transformation and gastric cancer showed a significant increase in the expression of Oct4 (the labeled area increased from 2% in the control to 6 and 16% in the gastritis and cancerous tissues, respectively), suggesting a role for Oct4 in the early stages of cancer development. Furthermore, the data revealed an alteration in the subcellular distribution of Oct4, possibly due to the inhibition of cytoplasm-to-nucleus translocation during carcinogenesis. In conclusion, this study demonstrates an alteration in the expression pattern and nuclear translocation of Oct4 during gastric carcinogenesis and may be helpful in designing new modalities for the early detection and/or therapy of gastric cancer.