Computer Based Melanocytic and Nevus Image Enhancement and Segmentation

Digital dermoscopy aids dermatologists in monitoring potentially cancerous skin lesions. Melanoma is the 5th common form of skin cancer that is rare but the most dangerous. Melanoma is curable if it is detected at an early stage. Automated segmentation of cancerous lesion from normal skin is the most critical yet tricky part in computerized lesion detection and classification. The effectiveness and accuracy of lesion classification are critically dependent on the quality of lesion segmentation. In this paper, we have proposed a novel approach that can automatically preprocess the image and then segment the lesion. The system filters unwanted artifacts including hairs, gel, bubbles, and specular reflection. A novel approach is presented using the concept of wavelets for detection and inpainting the hairs present in the cancer images. The contrast of lesion with the skin is enhanced using adaptive sigmoidal function that takes care of the localized intensity distribution within a given lesion’s images. We then present a segmentation approach to precisely segment the lesion from the background. The proposed approach is tested on the European database of dermoscopic images. Results are compared with the competitors to demonstrate the superiority of the suggested approach.

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Review of Various Tasks Performed in the Preprocessing Phase of a Diabetic Retinopathy Diagnosis System

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405615666190219102427 ◽

2020 ◽

Vol 16 (4) ◽

pp. 397-426

Author(s):

Muhammad Nadeem Ashraf ◽

Muhammad Hussain ◽

Zulfiqar Habib

Keyword(s):

Diabetic Retinopathy ◽

Blood Vessels ◽

Early Stage ◽

Spherical Shape ◽

Cost Effective ◽

Lesion Detection ◽

Diabetic Patients ◽

Cad System ◽

Non Invasive ◽

Optic Discs

Diabetic Retinopathy (DR) is a major cause of blindness in diabetic patients. The increasing population of diabetic patients and difficulty to diagnose it at an early stage are limiting the screening capabilities of manual diagnosis by ophthalmologists. Color fundus images are widely used to detect DR lesions due to their comfortable, cost-effective and non-invasive acquisition procedure. Computer Aided Diagnosis (CAD) of DR based on these images can assist ophthalmologists and help in saving many sight years of diabetic patients. In a CAD system, preprocessing is a crucial phase, which significantly affects its performance. Commonly used preprocessing operations are the enhancement of poor contrast, balancing the illumination imbalance due to the spherical shape of a retina, noise reduction, image resizing to support multi-resolution, color normalization, extraction of a field of view (FOV), etc. Also, the presence of blood vessels and optic discs makes the lesion detection more challenging because these two artifacts exhibit specific attributes, which are similar to those of DR lesions. Preprocessing operations can be broadly divided into three categories: 1) fixing the native defects, 2) segmentation of blood vessels, and 3) localization and segmentation of optic discs. This paper presents a review of the state-of-the-art preprocessing techniques related to three categories of operations, highlighting their significant aspects and limitations. The survey is concluded with the most effective preprocessing methods, which have been shown to improve the accuracy and efficiency of the CAD systems.

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Morphologic Features of Cutaneous T-Cell Lymphomas Using Dermoscopy and High Frequency Ultrasound

Journal of Clinical Medicine ◽

10.3390/jcm10010017 ◽

2020 ◽

Vol 10 (1) ◽

pp. 17

Author(s):

Iris Wohlmuth-Wieser ◽

Joel M. Ramjist ◽

Neil Shear ◽

Raed Alhusayen

Keyword(s):

T Cell ◽

High Frequency ◽

Early Stage ◽

Skin Lesions ◽

Diagnostic Tools ◽

Skin Thickness ◽

High Frequency Ultrasound ◽

T Cell Lymphomas ◽

Standardized Parameters ◽

Frequency Ultrasound

The diagnosis of cutaneous T-cell lymphomas (CTCL) is frequently delayed by a median of three years and requires the clinical evaluation of an experienced dermatologist and a confirmatory skin biopsy. Dermoscopy and high-frequency ultrasound (HFUS) represent two non-invasive diagnostic tools. While dermoscopy is inexpensive and widely used for the diagnosis of melanoma and non-melanoma skin cancers, HFUS of skin lymphomas represents a novel diagnostic approach that is not yet implemented in the routine dermatologic practice. The aim of our study was to prospectively assess skin lesions of patients with either CTCL patches or plaques with dermoscopy and HFUS and to compare the findings with atopic dermatitis (AD) and psoriasis. Thirteen patients with an established diagnosis of CTCL, psoriasis, or AD were studied: Dermoscopy features including spermatozoa-like structures and the presence of white scales could assist in differentiating between early-stage CTCL and AD. HFUS measurements of the skin thickness indicated increased epidermal-, thickness in CTCL, and psoriasis compared with AD. Our results support the use of dermoscopy as a useful tool to diagnose CTCL. HFUS could augment the dermatologic assessment, but further studies will be needed to define standardized parameters.

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Inhibition of Hippo Signaling Improves Skin Lesions in a Rosacea-Like Mouse Model

International Journal of Molecular Sciences ◽

10.3390/ijms22020931 ◽

2021 ◽

Vol 22 (2) ◽

pp. 931

Author(s):

Jihyun Lee ◽

Yujin Jung ◽

Seo won Jeong ◽

Ga Hee Jeong ◽

Gue Tae Moon ◽

...

Keyword(s):

Mouse Model ◽

Signaling Pathway ◽

Normal Skin ◽

Skin Lesions ◽

Hippo Signaling ◽

Vascular Endothelial ◽

Expression Levels ◽

Hippo Signaling Pathway ◽

Endothelial Growth Factor

The Hippo signaling pathway plays a key role in regulating organ size and tissue homeostasis. Hippo and two of its main effectors, yes-associated protein (YAP) and WWTR1 (WW domain-containing transcription regulator 1, commonly listed as TAZ), play critical roles in angiogenesis. This study investigated the role of the Hippo signaling pathway in the pathogenesis of rosacea. We performed immunohistochemical analyses to compare the expression levels of YAP and TAZ between rosacea skin and normal skin in humans. Furthermore, we used a rosacea-like BALB/c mouse model induced by LL-37 injections to determine the roles of YAP and TAZ in rosacea in vivo. We found that the expression levels of YAP and TAZ were upregulated in patients with rosacea. In the rosacea-like mouse model, we observed that the clinical features of rosacea, including telangiectasia and erythema, improved after the injection of a YAP/TAZ inhibitor. Additionally, treatment with a YAP/TAZ inhibitor reduced the expression levels of YAP and TAZ and diminished vascular endothelial growth factor (VEGF) immunoreactivity in the rosacea-like mouse model. Our findings suggest that YAP/TAZ inhibitors can attenuate angiogenesis associated with the pathogenesis of rosacea and that both YAP and TAZ are potential therapeutic targets for patients with rosacea.

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Possible Involvement of F1F0-ATP synthase and Intracellular ATP in Keratinocyte Differentiation in normal skin and skin lesions

Scientific Reports ◽

10.1038/srep42672 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 7

Author(s):

Xie Xiaoyun ◽

Han Chaofei ◽

Zeng Weiqi ◽

Chen Chen ◽

Lu Lixia ◽

...

Keyword(s):

Atp Synthase ◽

Normal Skin ◽

Skin Lesions ◽

Keratinocyte Differentiation ◽

Intracellular Atp ◽

F1f0 Atp Synthase

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Cutis Tricolor

Journal of Pediatric Neurology ◽

10.1055/s-0038-1667013 ◽

2018 ◽

Vol 16 (05) ◽

pp. 276-281

Author(s):

Martino Ruggieri ◽

Agata Polizzi ◽

Selene Mantegna ◽

Chiara Battaglini ◽

Concetta Pirrone ◽

...

Keyword(s):

Normal Skin ◽

Distinct Type ◽

Skin Lesions ◽

Nasal Bridge ◽

Phacomatosis Pigmentovascularis ◽

Skeletal Defects ◽

Skin Abnormalities ◽

Vertebral Defects ◽

Postzygotic Mutations ◽

Over Time

AbstractCutis tricolor is a skin abnormality consisting in a combination of congenital hyper- and hypopigmented skin lesions (in the form of paired macules, patches, or streaks) in close proximity to each other in a background of normal skin. It is currently regarded as a twin-spotting (mosaic) phenomenon. This phenomenon has been reported so far as a purely cutaneous trait, as a part of a complex malformation phenotype (Ruggieri–Happle syndrome), which includes distinct facial features, cataract, skull and vertebral defects, long bones dysplasia, corpus callosum, cerebellar and white matter anomalies, cavum vergae and holoprosencephaly, and other systemic abnormalities. Cutis tricolor has been also reported as a distinct type with multiple, disseminated smaller skin macules (cutis tricolor parvimaculata) or in association with other skin disturbances (e.g., phacomatosis achromico-melano-marmorata) or in the context of other neurocutaneous phenotypes (e.g., ataxia-telangiectasia and phacomatosis pigmentovascularis) or as a sign of complex malformation phenotypes (e.g., microcephaly and dwarfism). More than 20 studies reporting 40 cases are present in the literature with pure cutaneous or syndromic cutis tricolor phenomena and are analyzed in the present study, confirming and expanding the overall phenotype of cutis tricolor. In particular, (1) the skin abnormalities of the cutis tricolor do not evolve over time; (2) there is a typical facial phenotype with long, elongated face, thick and brushy eyebrows, hypertelorism, deep nasal bridge with large bulbous nose, and anteverted nostrils; (3) the skeletal defects are mild-to-moderate and do not progress or cause relevant orthopedic complications; (4) the neurological/behavioral phenotype does not progress and the paroxysmal events (if present) tend to decrease over time; (5) only three patients developed early onset (treatable) cataracts. Different pathologic hypotheses have been postulated, including, early or late postzygotic mutations involving the same gene loci (in the context of the so-called dydymotic theory): such mechanisms can explain the overall skin, bone, lens, and nervous system phenomena of migration of different streaks of clones in the different tissues.

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Rational Programming of Cas12a for Early-Stage Detection of COVID-19 by Lateral Flow Assay and Portable Real-Time Fluorescence Readout Facilities

Biosensors ◽

10.3390/bios12010011 ◽

2021 ◽

Vol 12 (1) ◽

pp. 11

Author(s):

Zhijian Yi ◽

Jean de Dieu Habimana ◽

Omar Mukama ◽

Zhiyuan Li ◽

Nelson Odiwuor ◽

...

Keyword(s):

Real Time ◽

Early Stage ◽

Limited Resource ◽

Lateral Flow ◽

Lateral Flow Assay ◽

Capture Probe ◽

Fluorescence Detector ◽

Lateral Flow Strip ◽

Global Pandemic ◽

Novel Approach

Coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 virus has led to a global pandemic with a high spread rate and pathogenicity. Thus, with limited testing solutions, it is imperative to develop early-stage diagnostics for rapid and accurate detection of SARS-CoV-2 to contain the rapid transmission of the ongoing COVID-19 pandemic. In this regard, there remains little knowledge about the integration of the CRISPR collateral cleavage mechanism in the lateral flow assay and fluorophotometer. In the current study, we demonstrate a CRISPR/Cas12a-based collateral cleavage method for COVID-19 diagnosis using the Cas12a/crRNA complex for target recognition, reverse transcription loop-mediated isothermal amplification (RT-LAMP) for sensitivity enhancement, and a novel DNA capture probe-based lateral flow strip (LFS) or real-time fluorescence detector as the parallel system readout facility, termed CRICOLAP. Our novel approach uses a customized reporter that hybridizes an optimized complementary capture probe fixed at the test line for naked-eye result readout. The CRICOLAP system achieved ultra-sensitivity of 1 copy/µL in ~32 min by portable real-time fluorescence detection and ~60 min by LFS. Furthermore, CRICOLAP validation using 60 clinical nasopharyngeal samples previously verified with a commercial RT-PCR kit showed 97.5% and 100% sensitivity for S and N genes, respectively, and 100% specificity for both genes of SARS-CoV-2. CRICOLAP advances the CRISPR/Cas12a collateral cleavage result readout in the lateral flow assay and fluorophotometer, and it can be an alternative method for the decentralized field-deployable diagnosis of COVID-19 in remote and limited-resource locations.

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Atomic Force Microscopy Applied to Atopic Dermatitis Study

Internal Medicine ◽

10.2478/inmed-2021-0171 ◽

2021 ◽

Vol 18 (4) ◽

pp. 21-28

Author(s):

Simona Maria Ţîrcă ◽

Ion Ţîrcă ◽

Marius Sorin Ciontea ◽

Florin Dumitru Mihălţan

Keyword(s):

Atomic Force Microscopy ◽

Atopic Dermatitis ◽

Structural Integrity ◽

Clinical Investigation ◽

Normal Skin ◽

Skin Lesions ◽

Force Microscopy ◽

Atomic Force ◽

Child Patient ◽

Surface Morphologies

Abstract Atopic dermatitis (AD)-the commonest inflammatory skin disease affects up to 25% of children and 2% to 5% of adults. Methods of the diagnostic provide expanded recommendations founded on available evidence. Morphological evaluation remains a principal feature of clinical investigation and the main criteria of diagnosis. Methods. We collected normal and affected skin from a 6-month child patient who was diagnosed through dermatologic examination. Clinical characteristics and the diagnosis of atopic dermatitis were in accordance with Hanifin and Rajka criteria. Morphology and structural integrity were investigated by Atomic Force Microscopy. Results. Optical and topography images indicate that in the case of AD skin lesions the cuticle structure was severely damaged and distorted with the flattening and grading of the plates, which have an irregular appearance. From the surface morphologies of the samples, we demonstrate that the shape of the corneocytes, with granular and elongated appearance, specific to normal skin is transformed by AD into broken and collapsed plates with discontinuous appearance. Conclusions. In the initial diagnosis of AD changes of the skin properties can be an indicator. Hanifin and Rajka criteria together with Atomic Force Microscopy can be a useful and necessary technique diagnosing cases of atopic dermatitis.

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AN EFFICIENT CHAOS-BASED OPTIMIZATION ALGORITHM APPROACH FOR CRYPTOGRAPHY

International Journal of Communication Networks and Security ◽

10.47893/ijcns.2012.1056 ◽

2012 ◽

pp. 75-79

Author(s):

RASHI VOHRA ◽

BRAJESH PATEL

Keyword(s):

Genetic Algorithm ◽

Optimization Algorithm ◽

Negative Impact ◽

Chaotic Map ◽

Pseudorandom Sequence ◽

Secure Communications ◽

Security Threats ◽

Suggested Approach ◽

Novel Approach ◽

Algorithm Operation

The utmost negative impact of advancement of technology is an exponential increase in security threats, due to which tremendous demand for effective electronic security is increasing importantly. The principles of any security mechanism are confidentiality, authentication, integrity, non-repudiation, access control and availability. Cryptography is an essential aspect for secure communications. Many chaotic cryptosystem has been developed, as a result of the interesting relationship between the two field chaos and cryptography phenomenological behavior. In this paper, an overview of cryptography, optimization algorithm and chaos theory is provided and a novel approach for encryption and decryption based on chaos and optimization algorithms is discussed. In this article, the basic idea is to encrypt and decrypt the information using the concept of genetic algorithm with the pseudorandom sequence further used as a key in genetic algorithm operation for encryption: which is generated by application of chaotic map. This attempt result in good desirable cryptographic properties as a change in key will produce undesired result in receiver side. The suggested approach complements standard, algorithmic procedures, providing security solutions with novel features.

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