Publications by authors named "Hong Liang Tey"

118 Publications

Response to Momen et al.'s "Discriminating 'DRESS minor' from 'DRESS major': facial oedema aligns to the severe phenotype."

J Am Acad Dermatol 2021 Jul 21. Epub 2021 Jul 21.

Department of Dermatology, National Skin Centre, 1 Mandalay Road, 308205; Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore. Electronic address:

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http://dx.doi.org/10.1016/j.jaad.2021.05.066DOI Listing
July 2021

Intranasal octenidine for methicillin-resistant (MRSA) carriers and universal octenidine bathing reduced MRSA acquisition in an acute-care general ward.

Infect Control Hosp Epidemiol 2021 Jul 16:1-4. Epub 2021 Jul 16.

Department of Clinical Epidemiology, Office of Clinical Epidemiology, Analytics and Knowledge, Tan Tock Seng Hospital, Singapore.

In this quasi-experimental before-and-after study in a methicillin-resistant staphylococcus aureus (MRSA) high-prevalence acute-care dermatology ward from August 2016 to November 2018, patients admitted during intervention period who received additional topical intranasal octenidine were 63% less likely to acquire MRSA than those receiving universal daily octenidine bathing alone during baseline period (aOR, 0.37; 95% CI, 0.14-0.98).
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http://dx.doi.org/10.1017/ice.2021.300DOI Listing
July 2021

Bullous eosinophilic annular erythema.

Dermatol Online J 2021 May 15;27(5). Epub 2021 May 15.

National Skin Centre.

Eosinophilic annular erythema is an idiopathic acute eosinophilic dermatosis. It is a rare condition, with approximately 30 cases reported in the English literature. It features annular, figurate urticarial edematous plaques primarily affecting the trunk and proximal limbs. During evaluation of a patient, secondary causes of eosinophilic inflammation such as allergy-related conditions (eczema, drug, urticaria, contact dermatitis), parasitic infestations, and autoimmune dermatoses will need to be excluded. We present an unusual case of a 47-year-old patient who developed this condition.
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http://dx.doi.org/10.5070/D327553623DOI Listing
May 2021

A clinico-pathological approach to management of atopic dermatitis.

Ann Acad Med Singap 2021 02;50(2):171-173

Dermatology, National Skin Centre, Singapore.

Recent research in atopic dermatitis (AD) has identified it to be a heterogeneous inflammatory skin disorder of different endotypes (immune polarisation of T-cell subsets and genetic mutations) underlying various phenotypes (age of onset, ethnicity, disease severity, etc.). The corresponding heterogeneity in underlying patho-mechanisms of the disease has resulted in an impetus towards an endotype-driven management of AD. We propose a practical approach that is based on classifying AD patients into intrinsic and extrinsic phenotypes and their corresponding underlying endotypes. This approach aims to provide a practical method that integrates recent understanding of AD pathogenesis for a targeted endotype-driven management of AD.
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February 2021

Acquired hypohidrosis following a drug reaction.

Ann Acad Med Singap 2021 Jan;50(1):103-104

Internal Medicine, Tan Tock Seng Hospital, Singapore.

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January 2021

The accuracy of healthcare worker versus self collected (2-in-1) Oropharyngeal and Bilateral Mid-Turbinate (OPMT) swabs and saliva samples for SARS-CoV-2.

PLoS One 2020 16;15(12):e0244417. Epub 2020 Dec 16.

Department of Respiratory & Critical Care Medicine, Changi General Hospital, Singapore, Singapore.

Background: Self-sampling for SARS-CoV-2 would significantly raise testing capacity and reduce healthcare worker (HCW) exposure to infectious droplets personal, and protective equipment (PPE) use.

Methods: We conducted a diagnostic accuracy study where subjects with a confirmed diagnosis of COVID-19 (n = 401) and healthy volunteers (n = 100) were asked to self-swab from their oropharynx and mid-turbinate (OPMT), and self-collect saliva. The results of these samples were compared to an OPMT performed by a HCW in the same patient at the same session.

Results: In subjects confirmed to have COVID-19, the sensitivities of the HCW-swab, self-swab, saliva, and combined self-swab plus saliva samples were 82.8%, 75.1%, 74.3% and 86.5% respectively. All samples obtained from healthy volunteers were tested negative. Compared to HCW-swab, the sensitivities of a self-swab sample and saliva sample were inferior by 8.7% (95%CI: 2.4% to 15.0%, p = 0.006) and 9.5% (95%CI: 3.1% to 15.8%, p = 0.003) respectively. The combined detection rate of self-swab and saliva had a sensitivity of 2.7% (95%CI: -2.6% to 8.0%, p = 0.321). The sensitivity of both the self-collection methods are higher when the Ct value of the HCW swab is less than 30. The specificity of both the self-swab and saliva testing was 100% (95% CI 96.4% to 100%).

Conclusion: Our study provides evidence that sensitivities of self-collected OPMT swab and saliva samples were inferior to a HCW swab, but they could still be useful testing tools in the appropriate clinical settings.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0244417PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7744114PMC
December 2020

Chilblain-like eruption in COVID-19 disease: possible pathogenetic role of temperature.

Eur J Dermatol 2020 Dec;30(6):764-765

National Skin Centre, Singapore, Woodlands Health Campus, Singapore, Yong Loo Lin School of Medicine, National University of Singapore, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.

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http://dx.doi.org/10.1684/ejd.2020.3943DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7880645PMC
December 2020

Isolated hypohidrosis: pathogenesis and treatment.

Eur J Dermatol 2020 Dec;30(6):680-687

National Skin Centre, Singapore, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore.

Background: Hypohidrosis can result in heat injury, a potentially fatal condition. The majority of hypohidrosis cases have no associated abnormalities or secondary causes, and are termed "isolated hypohidrosis". These are clinically divided into miliaria profunda (MP), acquired idiopathic generalized anhidrosis (AIGA) and idiopathic partial hypohidrosis (IPH). The pathogenesis of isolated hypohidrosis remains largely unknown and there is no established effective treatment.

Objectives: To elucidate the pathogenesis of isolated hypohidrosis using in vivo high-definition optical coherence tomography (HD-OCT) imaging and assess the therapeutic profile of oral retinoids for this condition.

Materials & Methods: We conducted a retrospective analysis on all patients with isolated hypohidrosis in our neuro-dermatology clinic over a 5.75-year period. All patients routinely underwent standardised exercising and whole-body starch-iodine testing, followed by non-invasive HD-OCT skin imaging. Patients' demographics, disease characteristics, histology and treatment history were analysed.

Results: Of the 51 patients identified with isolated hypohidrosis; 23 were diagnosed with MP, 14 with AIGA, and 14 with IPH. In these patients, HD-OCT imaging led to the identification of sub-stratum corneal hypo-refractile material with underlying dilated sweat ducts, not present in healthy controls. The size of this material was most pronounced in MP, followed by AIGA, and then IPH. Post-treatment, the material decreased in size. Treatment response was reported in 90.6% patients with isotretinoin and 75.0% with acitretin. No recurrence has been reported to date. Side effects were largely anticipated and common.

Conclusion: The pathogenesis of isolated hypohidrosis involves obstruction of sweat orifices at the stratum corneum. Treatment with oral retinoids, particularly isotretinoin, is effective and safe.
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http://dx.doi.org/10.1684/ejd.2020.3931DOI Listing
December 2020

Vitamin E in Atopic Dermatitis: From Preclinical to Clinical Studies.

Dermatology 2021 16;237(4):553-564. Epub 2020 Oct 16.

Research and Development Department, Davos Life Science, Singapore, Singapore.

Background: Oxidative stress and inflammation are some of the proposed mechanisms involved in the pathogenesis of atopic dermatitis (AD). Current pharmacotherapeutic approaches are effective yet they are not without adverse effects. Vitamin E has great potential as an adjunctive treatment for AD owing to its antioxidant and anti-inflammatory bioactivities.

Summary: This review article summarizes the current available evidence from cellular, animal and clinical studies on the relationship between vitamin E and AD. The future prospects of vitamin E are also discussed. Vitamin E in practice does not show any toxicity to humans within a range of reasonable dosage. Albeit rarely, vitamin E as a contact allergen should be considered. Collectively, this review envisaged vitamin E as an adjunctive treatment for AD patients. Future research on the distinct effects of different vitamin E isoforms as well as their delivery system in skin disorders is needed.
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http://dx.doi.org/10.1159/000510653DOI Listing
October 2020

Combinatorial Single-Cell Analyses of Granulocyte-Monocyte Progenitor Heterogeneity Reveals an Early Uni-potent Neutrophil Progenitor.

Immunity 2020 08 23;53(2):303-318.e5. Epub 2020 Jun 23.

Singapore Immunology Network (SIgN), A∗STAR (Agency for Science, Technology and Research), Biopolis, Singapore 138648, Singapore.

Granulocyte-monocyte progenitors (GMPs) have been previously defined for their potential to generate various myeloid progenies such as neutrophils and monocytes. Although studies have proposed lineage heterogeneity within GMPs, it is unclear if committed progenitors already exist among these progenitors and how they may behave differently during inflammation. By combining single-cell transcriptomic and proteomic analyses, we identified the early committed progenitor within the GMPs responsible for the strict production of neutrophils, which we designate as proNeu1. Our dissection of the GMP hierarchy led us to further identify a previously unknown intermediate proNeu2 population. Similar populations could be detected in human samples. proNeu1s, but not proNeu2s, selectively expanded during the early phase of sepsis at the expense of monocytes. Collectively, our findings help shape the neutrophil maturation trajectory roadmap and challenge the current definition of GMPs.
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http://dx.doi.org/10.1016/j.immuni.2020.06.005DOI Listing
August 2020

Research Techniques Made Simple: Optical Clearing and Three-Dimensional Volumetric Imaging of Skin Biopsies.

J Invest Dermatol 2020 07;140(7):1305-1314.e1

Singapore Immunology Network (SIgN), A*STAR (Agency for Science, Technology and Research), Biopolis, Singapore. Electronic address:

Skin histology is traditionally carried out using two-dimensional tissue sections, which allows for rapid staining, but these sections cannot accurately represent three-dimensional structures in skin such as nerves, vasculature, hair follicles, and sebaceous glands. Although it may be ideal to image skin in a three-dimensional manner, it is technically challenging to image deep into tissue because of light scattering from collagen fibrils in the dermis and refractive index mismatch owing to the presence of differing biological materials such as cytoplasm, and lipids in the skin. Different optical clearing methods have been developed recently, making it possible to render tissues transparent using different approaches. Here, we discuss the steps involved in tissue preparation for three-dimensional volumetric imaging and provide a brief overview of the different optical clearing methods as well as different imaging modalities for three-dimensional imaging.
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http://dx.doi.org/10.1016/j.jid.2020.04.014DOI Listing
July 2020

Reprint of "Multi-modal image cytometry approach - From dynamic to whole organ imaging".

Cell Immunol 2020 04 10;350:104086. Epub 2020 Mar 10.

Singapore Immunology Network (SIgN), A*STAR (Agency for Science, Technology and Research), Biopolis, 8A Biomedical Grove, Singapore 138648, Singapore; National Skin Centre, 1 Mandalay Road, Singapore 308205, Singapore. Electronic address:

Optical imaging is a valuable tool to visualise biological processes in the context of the tissue. Each imaging modality provides the biologist with different types of information - cell dynamics and migration over time can be tracked with time-lapse imaging (e.g. intra-vital imaging); an overview of whole tissues can be acquired using optical clearing in conjunction with light sheet microscopy; finer details such as cellular morphology and fine nerve tortuosity can be imaged at higher resolution using the confocal microscope. Multi-modal imaging combined with image cytometry - a form of quantitative analysis of image datasets - provides an objective basis for comparing between sample groups. Here, we provide an overview of technical aspects to look out for in an image cytometry workflow, and discuss issues related to sample preparation, image post-processing and analysis for intra-vital and whole organ imaging.
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http://dx.doi.org/10.1016/j.cellimm.2020.104086DOI Listing
April 2020

Techniques and Applications in Skin OCT Analysis.

Adv Exp Med Biol 2020 ;1213:149-163

Institute for Health Technologies, Nanyang Technological University, Singapore, Singapore.

The skin is the largest organ of our body. Skin disease abnormalities which occur within the skin layers are difficult to examine visually and often require biopsies to make a confirmation on a suspected condition. Such invasive methods are not well-accepted by children and women due to the possibility of scarring. Optical coherence tomography (OCT) is a non-invasive technique enabling in vivo examination of sub-surface skin tissue without the need for excision of tissue. However, one of the challenges in OCT imaging is the interpretation and analysis of OCT images. In this review, we discuss the various methodologies in skin layer segmentation and how it could potentially improve the management of skin diseases. We also present a review of works which use advanced machine learning techniques to achieve layers segmentation and detection of skin diseases. Lastly, current challenges in analysis and applications are also discussed.
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http://dx.doi.org/10.1007/978-3-030-33128-3_10DOI Listing
February 2020

Topical glycopyrrolate followed by microneedling: a novel treatment option for eccrine hidrocystomas.

J Dermatolog Treat 2020 Jan 23:1-2. Epub 2020 Jan 23.

Department of Dermatology, National Skin Centre, Singapore.

Eccrine hidrocystomas (EH) are benign cystic tumors of the eccrine glands with no established treatment yet. Eccrine glands are activated by acetylcholine released from innervating sympathetic nerve fibers. Use of oral anti-cholinergic agents is rare due to the possibility of systemic side effects while topical atropine and scopolamine have been found to be ineffective. In our patient, we tried using topical glycopyrrolate over the entire affected region followed by microneedling. Our aim was to create micro-channels through the epidermis and dermis, delivering the drug to EH lesions in the deeper dermis. We only performed microneedling over the left half of the chest to compare the difference made by microneedling. The effective percutaneous delivery of topical glycol was evident by our patient's transient systemic side effects and reduction of the EH lesions. Specifically, the lesions were reduced more significantly over the left where microneedles were applied. Our treatment was effective for our patient and he was satisfied with the improvement in cosmesis. The method described may serve as a therapeutic option for patients with EH.
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http://dx.doi.org/10.1080/09546634.2020.1716929DOI Listing
January 2020

Validating high-definition optical coherence tomography in filament measurements: A tool for in vivo measurement of hair shaft diameters.

Skin Res Technol 2020 05 27;26(3):447-448. Epub 2019 Nov 27.

National Skin Centre, Singapore City, Singapore.

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http://dx.doi.org/10.1111/srt.12808DOI Listing
May 2020

Dissolving Triamcinolone-Embedded Microneedles for the Treatment of Keloids: A Single-Blinded Intra-Individual Controlled Clinical Trial.

Dermatol Ther (Heidelb) 2019 Sep 2;9(3):601-611. Epub 2019 Aug 2.

National Skin Centre, Singapore, Singapore.

Introduction: Keloids are a prevalent chronic skin disorder with significant psychosocial morbidity. Intralesional corticosteroid injections are the first-line treatment but are painful and require repeated injections by medical professionals. Dissolving microneedles are a novel method of cutaneous drug delivery that induces minimal/no pain and can be self-administered. The objective of the study was to evaluate the efficacy and safety of triamcinolone-embedded dissolving microneedles in treatment of keloids.

Methods: This was a single-blind, intra-individual controlled two-phase clinical trial of 8-week duration each. Two keloids per subject were selected for (1) once-daily 2-min application with microneedles for 4 weeks, followed by no treatment for the next 4 weeks, or (2) non-intervention as control. Primary outcome was change in keloid volume as assessed by a high-resolution 3D scanner.

Results: There was significant reduction in keloid volume compared with controls after 4 weeks of treatment. This reduction was greater with a higher dosage of triamcinolone used.

Conclusions: Once-daily application of dissolving triamcinolone-embedded microneedles significantly reduced the volume of keloids. The treatment was safe, can be self-administered and can serve as an alternative for patients unsuitable for conventional treatments.

Trial Registration: Trial Registry: Health Science Authority (Singapore) Clinical Trials Register Registration number: 2015/00440.
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http://dx.doi.org/10.1007/s13555-019-00316-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6704225PMC
September 2019

Multi-modal image cytometry approach - From dynamic to whole organ imaging.

Cell Immunol 2019 Oct 2;344:103946. Epub 2019 Jul 2.

Singapore Immunology Network (SIgN), A*STAR (Agency for Science, Technology and Research), Biopolis, 8A Biomedical Grove, Singapore 138648, Singapore; National Skin Centre, 1 Mandalay Road, Singapore 308205, Singapore. Electronic address:

Optical imaging is a valuable tool to visualise biological processes in the context of the tissue. Each imaging modality provides the biologist with different types of information - cell dynamics and migration over time can be tracked with time-lapse imaging (e.g. intra-vital imaging); an overview of whole tissues can be acquired using optical clearing in conjunction with light sheet microscopy; finer details such as cellular morphology and fine nerve tortuosity can be imaged at higher resolution using the confocal microscope. Multi-modal imaging combined with image cytometry - a form of quantitative analysis of image datasets - provides an objective basis for comparing between sample groups. Here, we provide an overview of technical aspects to look out for in an image cytometry workflow, and discuss issues related to sample preparation, image post-processing and analysis for intra-vital and whole organ imaging.
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http://dx.doi.org/10.1016/j.cellimm.2019.103946DOI Listing
October 2019

Inter- and intra-observer agreement in dermatologists' diagnoses of hyperpigmented facial lesions and development of an algorithm for automated diagnosis.

Skin Res Technol 2019 Nov 22;25(6):777-786. Epub 2019 May 22.

Procter & Gamble International Operations SA SG Branch, Singapore, Singapore.

Background: Hyperpigmentation has varied aetio-pathologies. Hence, accurate and reproducible diagnosis of the type of hyperpigmentation is essential for effective management. It is typically made clinically by dermatologists but the rate of inter- and intra-observer agreement/variability is unknown. Hyperpigmented facial lesions are extremely common but access to dermatological services is difficult or costly in most countries. Thus, it is desired to evaluate dermatologists' inter- and intra-observer agreement in the diagnosis and to develop an algorithm for automated diagnosis.

Materials And Methods: Hyperpigmented lesions on 392 facial images were diagnosed by three experienced dermatologists either jointly or independently, and this process was subsequently repeated for 52 randomly selected images. When there was non-concordance amongst the dermatologists for the diagnosis, a majority decision was taken as correct diagnosis. Inter-observer and intra-observer agreement were analysed for the diagnosis of the hyperpigmented lesions. Thereafter, a multiclass classification method was developed to perform the task in an automatic manner. The developed algorithm was compared and validated against the ground truth derived from the dermatologists.

Results: Both inter- and intra-observer agreements are in the moderate range. The algorithm agreed well with the derived ground truth, with a Kappa value of 0.492, which is similar to the Kappa values of inter- and intra- observer agreements.

Conclusion: The rates of inter- and intra-observer agreement in the diagnosis of hyperpigmented facial lesions amongst dermatologists were moderate in this study. Compared to visual assessment from the dermatologists, automated diagnosis using the developed algorithm achieved a high rate of concordance.
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http://dx.doi.org/10.1111/srt.12717DOI Listing
November 2019

Idiopathic Generalized Exfoliative Dermatitis and Association with Antihypertensive Drugs and Statins: A Retrospective Case-Control Study.

Dermatology 2019 4;235(2):107-111. Epub 2019 Feb 4.

National Skin Centre, Singapore, Singapore.

Background/aims: We aim to examine the hypothesis that antihypertensive drugs and statins may be responsible for the development of idiopathic generalized exfoliative dermatitis (GED) with a case-control study.

Methods: All inpatients who were hospitalized under the dermatology service at the Tan Tock Seng Hospital, Singapore, between 1 May 2013 and 31 May 2015, were analysed. Idiopathic GED cases had consistent clinical and histological features but no apparent cause despite comprehensive evaluation. Controls were randomly selected from inpatients with other dermatological conditions in a 1: 1 ratio during the same period. Their relationship was analysed using univariate (χ2 or Fisher exact tests) and multivariate logistic regression analysis.

Results: There were 78 cases and 83 controls. Of the 78 cases, 42 patients had a history of treatment with antihypertensive drugs or statins. Cases were not found to be more likely on angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, β-blockers, calcium channel blockers, thiazides or statins compared to controls (OR: 0.81; 95% CI: 0.43-1.51; p = 0.507).

Conclusions: There was insufficient evidence to suggest a significant relationship between the chronic use of antihypertensive drugs or statins and idiopathic GED in this study, despite previous evidence reporting this might be so. Further case-control studies with larger sample sizes are needed to evaluate this association.
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http://dx.doi.org/10.1159/000495836DOI Listing
June 2019

Mapping of γ/δ T cells reveals Vδ2+ T cells resistance to senescence.

EBioMedicine 2019 Jan 7;39:44-58. Epub 2018 Dec 7.

Singapore Immunology Network (SIgN), Agency for Science Technology and Research (A*STAR), Immunos Building, Singapore 138648, Singapore; School of Biological Sciences, Nanyang Technological University, Singapore, Singapore; Department of Microbiology, National University of Singapore, Singapore, Singapore; Department of Biology, Faculty of Science, University Tunis El Manar, Tunis, Tunisia. Electronic address:

Background: Immune adaptation with aging is a major of health outcomes. Studies in humans have mainly focus on αβ T cells while γδ T cells have been neglected despite their role in immunosurveillance. We investigated the impact of aging on γδ T cell subsets phenotypes, functions, senescence and their molecular response to stress.

Methods: Peripheral blood of young and old donors in Singapore have been used to assess the phenotype, functional capacity, proliferation capacity and gene expression of the various γδ T cell subsets. Peripheral blood mononuclear cells from apheresis cones and young donors have been used to characterize the telomere length, epigenetics profile and DNA damage response of the various γδ T cell subsets phenotype.

Findings: Our data shows that peripheral Vδ2+ phenotype, functional capacity (cytokines, cytotoxicity, proliferation) and gene expression profile are specific when compared against all other αβ and γδ T cells in aging. Hallmarks of senescence including telomere length, epigenetic profile and DNA damage response of Vδ2+ also differs against all other αβ and γδ T cells.

Interpretation: Our results highlight the differential impact of lifelong stress on γδ T cells subsets, and highlight possible mechanisms that enable Vδ2+ to be resistant to cellular aging. The new findings reinforce the concept that Vδ2+ have an "innate-like" behavior and are more resilient to the environment as compared to "adaptive-like" Vδ1+ T cells.
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http://dx.doi.org/10.1016/j.ebiom.2018.11.053DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6354624PMC
January 2019

3-Dimensional Optical Clearing and Imaging of Pruritic Atopic Dermatitis and Psoriasis Skin Reveals Downregulation of Epidermal Innervation.

J Invest Dermatol 2019 05 22;139(5):1201-1204. Epub 2018 Nov 22.

National Skin Centre, Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore. Electronic address:

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http://dx.doi.org/10.1016/j.jid.2018.11.006DOI Listing
May 2019

Papular Purpuric Glove and Socks Syndrome with Evolution into Pemphigus Vulgaris.

Ann Acad Med Singap 2018 Oct;47(10):429-430

National Skin Centre, Singapore.

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October 2018

Three-dimensional graph-based skin layer segmentation in optical coherence tomography images for roughness estimation.

Biomed Opt Express 2018 Aug 6;9(8):3590-3606. Epub 2018 Jul 6.

National Skin Center, 1 Mandalay Road, 308205, Singapore.

Automatic skin layer segmentation in optical coherence tomography (OCT) images is important for a topographic assessment of skin or skin disease detection. However, existing methods cannot deal with the problem of shadowing in OCT images due to the presence of hair, scales, etc. In this work, we propose a method to segment the topmost layer of the skin (or the skin surface) using 3D graphs with a novel cost function to deal with shadowing in OCT images. 3D graph cuts use context information across B-scans when segmenting the skin surface, which improves the segmentation as compared to segmenting each B-scan separately. The proposed method reduces the segmentation error by more than 20% as compared to the best performing related work. The method has been applied to roughness estimation and shows a high correlation with a manual assessment. Promising results demonstrate the usefulness of the proposed method for skin layer segmentation and roughness estimation in both normal OCT images and OCT images with shadowing.
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http://dx.doi.org/10.1364/BOE.9.003590DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6191621PMC
August 2018

Streamlining volumetric multi-channel image cytometry using hue-saturation-brightness-based surface creation.

Commun Biol 2018 6;1:136. Epub 2018 Sep 6.

Singapore Immunology Network (SIgN), A*STAR (Agency for Science, Technology and Research), Biopolis, 138648, Singapore, Singapore.

Image cytometry is the process of converting image data to flow cytometry-style plots, and it usually requires computer-aided surface creation to extract out statistics for cells or structures. One way of dealing with structures stained with multiple markers in three-dimensional images, is carrying out multiple rounds of channel co-localization and image masking before surface creation, which is cumbersome and laborious. We propose the application of the hue-saturation-brightness color space to streamline this process, which produces complete surfaces, and allows the user to have a global view of the data before flexibly defining cell subsets. Spectral compensation can also be performed after surface creation to accurately resolve different signals. We demonstrate the utility of this workflow in static and dynamic imaging datasets of a needlestick injury on the mouse ear, and we believe this scalable and intuitive approach will improve the ease of performing histocytometry on biological samples.
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http://dx.doi.org/10.1038/s42003-018-0139-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6127105PMC
September 2018

Serum carcinoembryonic antigen as a clinical marker in hypohidrosis.

Int J Dermatol 2018 Dec 24;57(12):e162-e164. Epub 2018 Sep 24.

National Skin Centre, Singapore.

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http://dx.doi.org/10.1111/ijd.14229DOI Listing
December 2018

Delusion of Parasitosis: A Descriptive Analysis of 88 Patients at a Tertiary Skin Centre.

Ann Acad Med Singap 2018 07;47(7):266-268

Dermatology, National Skin Centre, Singapore.

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July 2018

Methotrexate for the Treatment of Recalcitrant Primary Localized Cutaneous Amyloidosis: A Case Series.

Acta Derm Venereol 2018 Oct;98(9):900-901

Department of Dermatology, Rush University, Chicago, USA.

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http://dx.doi.org/10.2340/00015555-2991DOI Listing
October 2018

Chronic Pruritus in the Geriatric Population.

Dermatol Clin 2018 Jul 20;36(3):199-211. Epub 2018 Mar 20.

Department of Dermatology and Cutaneous Surgery, Itch Center Miller School of Medicine, 1295 NW 14th Street, University of Miami Hospital South Building Suites K-M, Miami, FL 33125, USA.

Chronic pruritus (>6 week's duration) in the geriatric population (≥65 years old), is an increasing health care problem. The pathophysiologic predisposing factors are abnormalities of the epidermal barrier, immune system, and nervous system. Causes can be dichotomized into histaminergic and nonhistaminergic pruritus. Topical treatments are generally safe. Systemic treatments are chosen depending on the condition, comorbid diseases, and drug interactions. Treatment options are limited. Progress has been made in identifying itch-selective mediators over the last decade. Numerous new medications are currently undergoing clinical trials and they are anticipated to enter the clinics in the near future.
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http://dx.doi.org/10.1016/j.det.2018.02.004DOI Listing
July 2018
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