Nevin Manimala

J Imaging. 2021 Mar 8;7(3):49. doi: 10.3390/jimaging7030049.

ABSTRACT

Visual features and representation learning strategies experienced huge advances in the previous decade, mainly supported by deep learning approaches. However, retrieval tasks are still performed mainly based on traditional pairwise dissimilarity measures, while the learned representations lie on high dimensional manifolds. With the aim of going beyond pairwise analysis, post-processing methods have been proposed to replace pairwise measures by globally defined measures, capable of analyzing collections in terms of the underlying data manifold. The most representative approaches are diffusion and ranked-based methods. While the diffusion approaches can be computationally expensive, the rank-based methods lack theoretical background. In this paper, we propose an efficient Rank-based Diffusion Process which combines both approaches and avoids the drawbacks of each one. The obtained method is capable of efficiently approximating a diffusion process by exploiting rank-based information, while assuring its convergence. The algorithm exhibits very low asymptotic complexity and can be computed regionally, being suitable to outside of dataset queries. An experimental evaluation conducted for image retrieval and person re-ID tasks on diverse datasets demonstrates the effectiveness of the proposed approach with results comparable to the state-of-the-art.

PMID:34460705 | DOI:10.3390/jimaging7030049

J Imaging. 2020 Jul 30;6(8):75. doi: 10.3390/jimaging6080075.

ABSTRACT

The goal of no-reference image quality assessment (NR-IQA) is to predict the quality of an image as perceived by human observers without using any pristine, reference images. In this study, an NR-IQA algorithm is proposed which is driven by a novel feature vector containing statistical and perceptual features. Different from other methods, normalized local fractal dimension distribution and normalized first digit distributions in the wavelet and spatial domains are incorporated into the statistical features. Moreover, powerful perceptual features, such as colorfulness, dark channel feature, entropy, and mean of phase congruency image, are also incorporated to the proposed model. Experimental results on five large publicly available databases (KADID-10k, ESPL-LIVE HDR, CSIQ, TID2013, and TID2008) show that the proposed method is able to outperform other state-of-the-art methods.

PMID:34460690 | DOI:10.3390/jimaging6080075

J Imaging. 2021 Apr 28;7(5):81. doi: 10.3390/jimaging7050081.

ABSTRACT

The COVID-19 pandemic has been deemed a global health pandemic. The early detection of COVID-19 is key to combating its outbreak and could help bring this pandemic to an end. One of the biggest challenges in combating COVID-19 is accurate testing for the disease. Utilizing the power of Convolutional Neural Networks (CNNs) to detect COVID-19 from chest X-ray images can help radiologists compare and validate their results with an automated system. In this paper, we propose a carefully designed network, dubbed CORONA-Net, that can accurately detect COVID-19 from chest X-ray images. CORONA-Net is divided into two phases: (1) The reinitialization phase and (2) the classification phase. In the reinitialization phase, the network consists of encoder and decoder networks. The objective of this phase is to train and initialize the encoder and decoder networks by a distribution that comes out of medical images. In the classification phase, the decoder network is removed from CORONA-Net, and the encoder network acts as a backbone network to fine-tune the classification phase based on the learned weights from the reinitialization phase. Extensive experiments were performed on a publicly available dataset, COVIDx, and the results show that CORONA-Net significantly outperforms the current state-of-the-art networks with an overall accuracy of 95.84%.

PMID:34460677 | DOI:10.3390/jimaging7050081

J Imaging. 2020 Jul 2;6(7):60. doi: 10.3390/jimaging6070060.

ABSTRACT

Image fusion is a process that integrates similar types of images collected from heterogeneous sources into one image in which the information is more definite and certain. Hence, the resultant image is anticipated as more explanatory and enlightening both for human and machine perception. Different image combination methods have been presented to consolidate significant data from a collection of images into one image. As a result of its applications and advantages in variety of fields such as remote sensing, surveillance, and medical imaging, it is significant to comprehend image fusion algorithms and have a comparative study on them. This paper presents a review of the present state-of-the-art and well-known image fusion techniques. The performance of each algorithm is assessed qualitatively and quantitatively on two benchmark multi-focus image datasets. We also produce a multi-focus image fusion dataset by collecting the widely used test images in different studies. The quantitative evaluation of fusion results is performed using a set of image fusion quality assessment metrics. The performance is also evaluated using different statistical measures. Another contribution of this paper is the proposal of a multi-focus image fusion library, to the best of our knowledge, no such library exists so far. The library provides implementation of numerous state-of-the-art image fusion algorithms and is made available publicly at project website.

PMID:34460653 | DOI:10.3390/jimaging6070060

J Orthop Res. 2021 Aug 30. doi: 10.1002/jor.25176. Online ahead of print.

ABSTRACT

Injured tendons do not regain their native structure except at fetal or very young ages. Healing tendons often show mucoid degeneration involving accumulation of sulfated glycosaminoglycans (GAGs), but its etiology and molecular base have not been studied substantially. We hypothesized that quality and quantity of gene expression involving synthesis of proteoglycans having sulfated GAGs are altered in injured tendons and that a reduction in synthesis of sulfated GAGs improves structural and functional recovery of injured tendons. C57BL6/j mice were subjected to the Achilles tendon tenotomy surgery. The injured tendons accumulated sulfate proteoglycans as early as 1-week postsurgery and continued so by 4-week postsurgery. Transcriptome analysis revealed upregulation of a wide range of proteoglycan genes that have sulfated GAGs in the injured tendons 1 and 3 weeks postsurgery. Genes critical for enzymatic reaction of initiation and elongation of chondroitin sulfate GAG chains were also upregulated. After the surgery, mice were treated with the 2-deoxy-D-glucose (2DG) that inhibits conversion of glucose to glucose-6-phosphate, an initial step of glucose metabolism as an energy source and precursors of monosaccharides of GAGs. The 2DG treatment reduced accumulation of sulfated proteoglycans, improved collagen fiber alignment and reduced the cross-sectional area of the injured tendons. The modulus of the 2DG-treated groups were higher than that in the vehicle group, but not of statistical significance. Our findings suggest that mucoid degeneration in injured tendons may result from upregulated expression of genes involved synthesis of sulfate proteoglycans and can be inhibited by reduction of glucose utilization. This article is protected by copyright. All rights reserved.

PMID:34460123 | DOI:10.1002/jor.25176

J Med Virol. 2021 Aug 30. doi: 10.1002/jmv.27311. Online ahead of print.

ABSTRACT

OBJECTIVE: to analyze the distribution of HPV genotype, cytology and the clinical characteristics of VaIN.

METHODS: All patients with histological-proven VaIN at West China Second University Hospital, between January 1, 2014, and October 1, 2020 were retrospectively identified. Demographics, medical history, HPV genotype, viral load and cytology results were retrieved. Standard statistical analyses were conducted.

RESULTS: Of 3229 patients included, 42.3% were diagnosed with VaIN 1, 30.3% with VaIN 2 and 27.4% with VaIN 3. Patients with VaIN 3 were the oldest (p<0.001). The leading HPV genotypes were HPV 16, 52, 58, 53, 56 and 81. The positive rate HPV 16 was positively correlated with the grade of VaIN and infected most of VaIN 3 patients (76.0%). The sensitivities of cytology for VaIN only, concomitant VaIN and VaIN after hysterectomy were 75.6%, 78.8% and 82.9%, respectively (p=0.013), and the sensitivities of HPV were 91.1%, 93.5% and 91.7%, respectively (p=0.205). Cotesting improved the sensitivities, up to 96.9%, 97.1% and 98.1%, respectively.

CONCLUSIONS: VaIN can occur alone or be concomitant with cervical or vulvar intraepithelial neoplasia. Most of VaIN 2/3 are infected with HPV 16. The sensitivity of cytology and HPV testing is non-inferior to that of CIN 2+. Therefore, these testing might be helpful in the early detection of VaIN. This article is protected by copyright. All rights reserved.

PMID:34460120 | DOI:10.1002/jmv.27311

Int J Cancer. 2021 Aug 30. doi: 10.1002/ijc.33786. Online ahead of print.

ABSTRACT

Acidity in the tumor microenvironment has been reported to promote cancer growth and metastasis. In this study, we examined a potential relation between extracellular acidity and expression level of the immune checkpoint molecule PD-L1 in murine squamous cell carcinoma (SCC) and melanoma cell lines. PD-L1 expression in the tumor cells was upregulated by culturing in a low pH culture medium. Tumor-bearing mice were allowed to ingest sodium bicarbonate, resulting in neutralization of acidity in the tumor tissue, a decrease in PD-L1 expression in tumor cells, and suppression of tumor growth in vivo. Proton-sensing G protein-coupled receptors (GPCRs), T cell death-associated gene 8 (TDAG8) and ovarian cancer G-protein-coupled receptor 1 (OGR1), were upregulated by low pH, and essentially involved in the acidity-induced elevation of PD-L1 expression in the tumor cells. Human head and neck SCC RNAseq data from the Cancer Genome Atlas also suggested a statistically significant correlation between expression levels of the proton sensors and PD-L1 mRNA expression. These findings strongly suggest that neutralization of acidity in tumor tissue may result in reduction of PD-L1 expression, potentially leading to inhibition of an immune check point and augmentation of anti-tumor immunity.

PMID:34460096 | DOI:10.1002/ijc.33786

Ther Innov Regul Sci. 2021 Aug 30. doi: 10.1007/s43441-021-00336-2. Online ahead of print.

ABSTRACT

BACKGROUND: Growing interest in improving patient participation convenience and the feasible execution of clinical trials has increased demand for new approaches to leverage patient input in the protocol design process.

METHODS: This study builds on prior work conducted by the Tufts Center for the Study of Drug Development in collaboration with ZS. A comprehensive participant burden algorithm based on protocol procedures, participation requirements and lifestyle preferences was developed and tested. Clinical trial preferences and perceptions from 3002 global patients were analyzed to inform and derive the algorithm. It was next tested against a convenience sample of 266 completed protocols. Descriptive statistics, significance tests, and regression analyses were performed.

RESULTS: Mean participant burden scores were highly associated with, and predictive (p < 0.01) of, screen failure rates, overall clinical trial duration and the number of substantial protocol amendments; and predictive (p < 0.05) of protocol treatment duration. Of 11 subgroups assessed, those that most influenced the algorithm and drove higher overall burden scores included disease condition, caregiver reliance, race, prior experience as a clinical trial participant and participant age. Geographic area and participant sex showed only minimal influence.

CONCLUSION: This study presents advancement and refinement in measuring participation burden that will assist drug development teams and protocol authors in retrospectively understanding clinical trial performance outcomes and in prospectively informing protocol design decisions.

PMID:34460095 | DOI:10.1007/s43441-021-00336-2

Neurol Ther. 2021 Aug 30. doi: 10.1007/s40120-021-00277-w. Online ahead of print.

ABSTRACT

INTRODUCTION: According to the official Russian source, in 2017 only 0.27% of the population of Russia was diagnosed with International Classification of Diseases, tenth revision (ICD-10) F4 category disorders (neurotic, stress-related and somatoform disorders), despite these disorders being among the most prevalent mental disorders worldwide. Here we report the results of a large-scale survey among Russian psychiatrists with the primary objective to assess the proportion of psychiatrists who use the diagnoses of interest (mixed anxiety and depression disorder [MADD], adjustment disorder [AdD], panic disorder [PD], agoraphobia, generalized anxiety disorder [GAD], social phobia, simple phobia, acute stress disorder and posttraumatic stress disorder) and compare results with those of a recent World Psychiatric Association (WPA) and World Health Organization (WHO) survey. We also compared the incidence of these diagnoses between state and non-state psychiatric services in Russia.

METHODS: Mean proportions and distribution of proportions of participants who made diagnoses of interest at different rates were calculated and compared with the results of the recent WPA and WHO survey. Risk ratios (RR) of the incidence of these diagnoses made at a frequency of at least once a week were calculated to compare state and non-state psychiatric services. The 95% confidence intervals of the RRs were calculated using the Koopman asymptotic score method.

RESULTS: Responses of 960 Russian psychiatrists were included in the analysis. Of these 95, 89 and 87% reported making diagnoses of MADD, AdD and PD, respectively, during the preceding 12 months, a far larger proportion compared to other disorders of interest. In general, a significantly smaller proportion of participants in our survey made diagnoses of anxiety disorders compared to respondents in the international WPA-WHO survey. Based on RRs, diagnoses of MADD, AdD, PD, GAD and acute stress disorder were less frequently made in the state-operated psychiatric service.

CONCLUSION: Our survey revealed a serious underdiagnosis of anxiety disorders in Russia that may be associated with complex factors that include, but are not limited to the current stigma associated with the state-operated psychiatric service, which is still the exclusive source of official statistical data in Russia.

PMID:34460079 | DOI:10.1007/s40120-021-00277-w

Inflammation. 2021 Aug 30. doi: 10.1007/s10753-021-01520-0. Online ahead of print.

ABSTRACT

Plasminogen activator inhibitor-1 (PAI-1) antagonists are known for their neuroprotective effects. In this study, it was aimed to investigate the possible protective effects of PAI-1 antagonists in a rat mild traumatic brain injury (TBI) model. Sprague-Dawley male rats were grouped as sham (n = 7), TBI (n = 9), and TBI + PAI-1 antagonist (5 and 10 mg/kg TM5441 and TM5484; n = 6-7). Under anesthesia, TBI was induced by dropping a metal 300-g weight from a height of 1 m on the skull. Before and 24-h after trauma neurological examination, tail suspension, Y-maze, and novel object recognition tests were performed. Twenty-four hours after TBI, the rats were decapitated and activities of myeloperoxidase, nitric oxide release, luminol-, and lucigenin-enhanced chemiluminescence were measured. Also, interleukin-1β, interleukin-6, tumor necrosis factor, interleukin-10, tumor growth factor-β, caspase-3, cleaved caspase-3, and PAI levels were measured with the ELISA method in the brain tissue. Brain injury was graded histopathologically following hematoxylin-eosin staining. Western blot and immunohistochemical investigation for low-density lipoprotein receptor, matrix metalloproteinase-3, and nuclear factor-κB were also performed. Data were analyzed using GraphPad Prism 8.0 (GraphPad Software, San Diego, CA, USA) and expressed as means ± SEM. Values of p < 0.05 were considered to be statistically significant. Higher levels of myeloperoxidase activity in the TBI group (p < 0.05) were found to be suppressed in 5 and 10 mg/kg TM5441 treatment groups (p < 0.05-p < 0.01). The tail suspension test score was increased in the TBI group (p < 0.001) and decreased in all treatment groups (p < 0.05-0.001). The histologic damage score was increased statistically significantly in the cortex, dentate gyrus, and CA3 regions in the TBI group (p < 0.01-0.001), decreased in the treatment groups in the cortex and dentate gyrus (p < 0.05-0.001). PAI antagonists, especially TM5441, have antioxidant and anti-inflammatory properties against mild TBI in the acute period. Behavioral test results were also improved after PAI antagonist treatment after mild TBI.

PMID:34460025 | DOI:10.1007/s10753-021-01520-0