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1.
Front Immunol ; 13: 1028435, 2022.
Article in English | MEDLINE | ID: mdl-36466878

ABSTRACT

Inflammatory skin conditions are the 4th leading cause of non-fatal health burden in the general population worldwide. The diagnosis of skin lesions due to systemic drug reactions, viral or bacterial exanthems, or in patients with psoriasis, atopic dermatitis or contact dermatitis is often difficult and relies heavily upon conventional histopathologic examination. Conversely, it is widely accepted that the cutaneous profile of inflammatory markers, or 'inflammatory signature', is differentially expressed in various skin conditions. In this pilot study, we investigated the possibility of inflammatory skin disease diagnosis from an immunological perspective in small punch biopsies. We collected lesional and perilesional punch biopsies from 139 patients suffering from a variety of inflammatory skin conditions and attending the Dermatology Department at the Princess Alexandra Hospital in Brisbane, Australia. Using bead-based immunoassays we were able to measure 13 out of 17 inflammatory markers from a pre-selected multi-analyte panel and to detect significant differences between lesional and perilesional biopsies from each individual patient. Hierarchical and unbiased clustering methods based on inflammatory signatures grouped psoriasis and atopic dermatitis lesions into individual clusters in contrast to other skin conditions, highlighting the potential of inflammatory signatures to be used as diagnostic differentiators and to inform alternative targets in anti-inflammatory treatment strategies.


Subject(s)
Dermatitis, Atopic , Psoriasis , Humans , Cytokines , Dermatitis, Atopic/diagnosis , Pilot Projects , Chemokines , Psoriasis/diagnosis
2.
Anal Chem ; 94(42): 14573-14582, 2022 10 25.
Article in English | MEDLINE | ID: mdl-36222247

ABSTRACT

Immune checkpoint blockade (ICB) therapy has achieved remarkable success in many cancers including melanoma. However, ICB therapy benefits only a small proportion of patients and produces severe side effects for some patients. Thus, there is an urgent need to identify patients who are more likely to respond to ICB therapy to improve outcomes and minimize side effects. To predict ICB therapy responses, we design a surface-enhanced Raman scattering (SERS) assay for multiplex profiling of circulating tumor cells (CTCs) under basal and interferon-γ (IFN-γ) stimulation. Through simultaneous ensemble and single-cell measurements of CTCs, the SERS assay can reveal tumor heterogeneity and offer a comprehensive CTC phenotype for decision-making. Anisotropic gold-silver alloy nanoboxes are utilized as SERS plasmonic substrates for improved signal readouts of CTC surface biomarkers. By generating a unique CTC signature with four surface biomarkers, the developed assay enables the differentiation of CTCs from three different patient-derived melanoma cell lines. Significantly, in a cohort of 14 melanoma patients who received programmed cell death-1 blockade therapy, the changes of CTC signature induced by IFN-γ stimulation to CTCs show the potential to predict responders. We expect that the SERS assay can help select patients for receiving ICB therapy in other cancers.


Subject(s)
Melanoma , Neoplastic Cells, Circulating , Humans , Immune Checkpoint Inhibitors , Silver , Interferon-gamma , Melanoma/drug therapy , Melanoma/pathology , Gold , Biomarkers , Alloys
3.
ISME Commun ; 2(1): 13, 2022 Feb 01.
Article in English | MEDLINE | ID: mdl-37938715

ABSTRACT

Actinic keratoses (AK) arise in severely photo-damaged skin and can progress to squamous cell carcinomas (SCC). AK and SCC are common in Caucasian populations, and immunosuppressed individuals have a markedly higher risk of developing SCC. An overabundance of Staphylococcus aureus has been reported in AK and SCC lesions of immunocompetent individuals, however, the AK/SCC microbiome in immunosuppressed cohorts has not been investigated. Here, the microbial profile and bacterial load of AK, SCC and control skin swabs from 32 immunosuppressed organ transplant recipients were characterised via SSU rRNA gene sequencing and qPCR, and compared to a previously described immunocompetent cohort. Although the taxonomic composition of skin swab samples was mostly subject-specific, significant differences were observed between control skin, AK, and SCC in both cohorts. Surface bacterial load was increased and alpha diversity decreased in AK and SCC compared to control skin due to an increased abundance of Staphylococcus species and relative decrease of skin commensals. Staphylococcus epidermidis predominated on SCC from transplant recipients in contrast to SCC of immunocompetent subjects dominated by S. aureus. In conclusion, AK and SCC of immunosuppressed and immunocompetent subjects present with distinctive microbial dysbioses, which may be relevant to SCC pathogenesis and progression.

4.
Anal Chem ; 93(50): 16787-16795, 2021 12 21.
Article in English | MEDLINE | ID: mdl-34889595

ABSTRACT

Epithelial to mesenchymal transition (EMT) results in the genesis of circulating tumor cells (CTCs) from tumor sites and promotes the metastatic capability of CTCs in circulation. In this study, we develop a multiplex surface-enhanced Raman scattering nanotechnology for comprehensive characterization of EMT-associated phenotypes in CTCs, to monitor cancer metastasis. We observe the downregulation of the CTC marker (EpCAM) and the epithelial marker (E-cadherin), as well as the upregulation of a mesenchymal marker (N-cadherin) and a stem cell marker (ABCB5) during the transforming growth factor-ß-induced EMT process in breast cancer cell line models. Additionally, we also find changes in the heterogeneity levels of these selected markers in cells. With this method, we successfully detect the presence of disease in samples from breast cancer patients and characterize EMT-associated phenotypes in their CTCs. Overall, this approach and findings provide a new means for monitoring the EMT process in cancer, insights into the detailed mechanistic progress of the diseases, and have potential for detecting the early occurrence of cancer metastasis.


Subject(s)
Epithelial-Mesenchymal Transition , Neoplasms , Humans
5.
Int J Cosmet Sci ; 43(6): 738-747, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34757625

ABSTRACT

OBJECTIVE: Microneedle or fractional laser applications are the most common topical delivery enhancement platforms. However, these methods of drug delivery are not skin strata specific. Drug delivery approaches which could target specific stratum of the skin remains a challenge. Elongated microparticles (EMPs) have been used in enhancing drug delivery into the skin. The aim of this study was to evaluate, for the first time, elongated silica microparticles with two different length profiles to enhance delivery of hyaluronic acid into different strata of human skin. METHODS: Two types of EMPs-long (milled EMPs) or short (etched EMPs) length ranges were characterized. A prototypical liquid formulation (Fluorescent hyaluronic acid) with and without EMP enhancement were evaluated for hyaluronic acid delivery in ex-vivo human skin. High performance liquid chromatography, Typhoon fluorescence scanning system, laser scanning confocal microscopy and reflectance confocal microscopy (RCM) were used to validate F-HA stability, visualize fluorescein in the skin, image the depth of F-HA delivery in the skin and define EMP penetration in skin strata, respectively. Statistical analysis was conducted using GraphPad Prism 6 software (GraphPad Software Inc, USA). RESULTS: Fluorescein-hyaluronic acid was stable and EMP enhanced skin penetration. RCM revealed that 'etched EMP' penetrated the skin to the stratum spinosum level. The vast majority (97.8%; p < 0.001) of the etched EMP did not penetrate completely through the viable epidermis and no obvious penetration into the dermis. In contrast, milled EMP showed 41-fold increase in penetration compared to the etched EMP but penetrated beyond the dermoepidermal junction. CONCLUSION: EMPs can enhance delivery of hyaluronic acid. Using EMPs with defined length distributions, which can be tuned for a specific stratum of the skin, can achieve targeted hyaluronic acid delivery.


OBJECTIF: Les microaiguilles ou le laser fractionné sont couramment utilisés pour augmenter l'absorption d'actif appliqué par voie topique. Toutefois, ces approches ne permettent de cibler une strate spécifique de la peau. Ainsi les méthodes permettant de cibler spécifiquement l'épiderme reste un défi. Les microparticules allongées (EMP) ont déjà été utilisé pour augmenter l'absorption cutanée. L'objectif de l'étude est d'évaluer pour la première fois, la capacité de microparticules allongées de silice (de deux longueurs différentes) à délivrer l'acide hyaluronique dans les différentes couches de la peau. MÉTHODES: Deux types d'EMP, longues (EMP broyé) ou courtes (EMP gravé), ont été caractérisées. Une formulation liquide contenant de l'acide hyaluronique marquée avec une sonde fluorescente (F-HA) a été évaluée avec et sans EMP sur peau humaine ex vivo. La chromatographie liquide haute performance, le scanner à fluorescence Typhoon, la microscopie laser confocal à balayage et la microscopie confocale par réflectance (RCM) ont été utilisées respectivement pour contrôler la stabilité de la F-HA, visualiser le signal de la fluorescéine dans la peau, imager l'absorption du F-HA dans la peau en fonction de la profondeur et caractériser la pénétration des EMP. Les analyses statistiques ont été réalisées avec le logiciel GraphPad Prims 6 (GraphPad Software Inc, USA). RÉSULTATS: L'acide hyaluronique marquée avec la fluorescéine est stable et les EMP permettent d'augmenter son absorption cutanée. Le RCM a montré que les EMP gravées pénètrent dans la peau jusqu'au niveau du stratum spinosum. La grande majorité des EMP gravés (97.8% ; p < 0,001) ne pénètre pas complétement dans l'épiderme viable et aucune pénétration mesurable dans le derme. Au contraire, les EMP broyées ont montrées une pénétration 41 fois plus importantes que les EMP gravées et peuvent aller au-delà de la jonction derme-épiderme. CONCLUSION: Les EMP peuvent augmenter l'absorption cutanée de l'acide hyaluronique. En utilisant des EMP de longueur définie et en ajustant celle-ci, il est même possible de cibler spécifiquement une strate cutanée.


Subject(s)
Administration, Cutaneous , Drug Delivery Systems/methods , Hyaluronic Acid/administration & dosage , Silicon Dioxide/chemistry , Skin/drug effects , Humans
6.
Int J Cosmet Sci ; 42(5): 462-470, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32619281

ABSTRACT

OBJECTIVE: This proof-of-concept study demonstrated that using minimally invasive skin microsampling could enable significantly higher throughput of cosmetic testing in volunteers than conventional biopsy. Nanoparticle sunscreen was used as a model to test toxicity based on oxidative stress using microbiopsy and confocal imaging. METHODS: Six volunteers were recruited for this study (3 males and 3 females). Zinc oxide nanoparticle containing topical formulation was prepared at 10% w/v. Each volunteer had 3 areas of 4 cm2 each mapped on each inner forearm for a total of 6 treatment areas (intact/ tape-stripped and with/without treatment). The topical zinc-nanoparticle formulation was applied directly to volunteer skin (2mg/cm2 ) for 2 hrs. Microbiopsied tissue from each treatment group was stained for reactive oxygen and nitrogen species in addition to mitochondrial superoxide. The stained samples were then imaged using confocal microscopy prior to image analysis. RESULTS: Skin exposed to zinc oxide nanoparticles did not show any significant increases in oxidative stress. Zinc oxide nanoparticle tape-stripped skin resulted in signal significantly lower (P < 0.001) oxidative stress levels than t-butylated hydroxytoluene treated tape-stripped skin for oxidative stress markers. Topically applied zinc oxide nanoparticles had no detectable effect on the oxidative status in volunteer skin. No adverse reactions or effects were observed after all treatments including microbiopsy. CONCLUSION: The data support the hypothesis that microbiopsy is a viable approach to study cosmeceutical- skin interactions in volunteers with capacity for molecular assays and high throughput with very low risk to the volunteer.


OBJECTIFS: Cette étude de validation de concept a démontré que le microprélèvement cutané minimalement invasif pouvait augmenter considérablement la cadence des essais de produits cosmétiques sur des volontaires par rapport à une biopsie conventionnelle. Un écran solaire contenant des nanoparticules a été utilisé comme modèle pour tester la toxicité liée au stress oxydatif à l'aide de la microbiopsie et de l'imagerie confocale. MÉTHODES: Six volontaires ont été recrutés pour cette étude (3 hommes et 3 femmes). Une formulation topique contenant des nanoparticules d'oxyde de zinc a été préparée à 10 % p/v. Chaque volontaire disposait de 3 zones de 4 cm2 situées sur chaque pliure de coude pour un total de 6 zones de traitement (intactes / strippée et avec / sans traitement). La formulation topique contenant des nanoparticules d'oxyde de zinc a été appliquée directement sur la peau des volontaires (2 mg/cm2 ) pendant 2 heures. Les tissus microbiopsiés de chaque groupe de traitement ont été colorés pour détecter des espèces réactives de l'oxygène et de l'azote en plus de la superoxyde mitochondriale. Les échantillons colorés ont ensuite été examinés par microscopie confocale avant l'analyse des images. RÉSULTATS: La peau exposée aux nanoparticules d'oxyde de zinc n'a pas montré de hausse significative de stress oxydatif. La peau strippée traitée aux nanoparticules d'oxyde de zinc a entraîné des niveaux de stress oxydatif nettement inférieurs (p<0,001) comparés à ceux de la peau strippée traitée à l'hydroxytoluène t-butylé en ce que concerne les marqueurs de stress oxydatif. Les nanoparticules d'oxyde de zinc appliquées par voie topique n'ont eu aucun effet détectable sur l'état oxydatif de la peau des volontaires. Aucune réaction ou effet indésirable n'a été observé(e) après tous les traitements, y compris la microbiopsie. CONCLUSION: Les données obtenues étayent l'hypothèse selon laquelle la microbiopsie est une approche viable pour étudier les interactions des produits cosmétiques sur la peau des volontaires, avec la possibilité de réaliser des dosages moléculaires et à haut débit, avec un risque très faible pour les volontaires.


Subject(s)
Biopsy/methods , Microscopy, Confocal/methods , Oxidative Stress , Sunscreening Agents/toxicity , Humans , Metal Nanoparticles/chemistry , Proof of Concept Study , Zinc Oxide/administration & dosage
7.
Sci Adv ; 6(9): eaax3223, 2020 02.
Article in English | MEDLINE | ID: mdl-32133394

ABSTRACT

Monitoring targeted therapy in real time for cancer patients could provide vital information about the development of drug resistance and improve therapeutic outcomes. Extracellular vesicles (EVs) have recently emerged as a promising cancer biomarker, and EV phenotyping shows high potential for monitoring treatment responses. Here, we demonstrate the feasibility of monitoring patient treatment responses based on the plasma EV phenotypic evolution using a multiplex EV phenotype analyzer chip (EPAC). EPAC incorporates the nanomixing-enhanced microchip and the multiplex surface-enhanced Raman scattering (SERS) nanotag system for direct EV phenotyping without EV enrichment. In a preclinical model, we observe the EV phenotypic heterogeneity and different phenotypic responses to the treatment. Furthermore, we successfully detect cancer-specific EV phenotypes from melanoma patient plasma. We longitudinally monitor the EV phenotypic evolution of eight melanoma patients receiving targeted therapy and find specific EV profiles involved in the development of drug resistance, reflecting the potential of EV phenotyping for monitoring treatment responses.


Subject(s)
Extracellular Vesicles/metabolism , Melanoma/blood , Microarray Analysis , Spectrum Analysis, Raman , Cell Line, Tumor , Extracellular Vesicles/pathology , Female , Humans , Male , Melanoma/pathology , Melanoma/therapy
8.
Small ; 16(13): e1905614, 2020 04.
Article in English | MEDLINE | ID: mdl-32141228

ABSTRACT

Epithelial-mesenchymal transition (EMT) is a primary mechanism for cancer metastasis. Detecting the activation of EMT can potentially convey signs of metastasis to guide treatment management and improve patient survival. One of the classic signatures of EMT is characterized by dynamic changes in cellular expression levels of E-cadherin and N-cadherin, whose soluble active fragments have recently been reported to be biomarkers for cancer diagnosis and prognosis. Herein, a microfluidic immunoassay (termed "SERS immunoassay") based on sensitive and simultaneous detection of soluble E-cadherin (sE-cadherin) and soluble N-cadherin (sN-cadherin) for EMT monitoring in patients' plasma is presented. The SERS immunoassay integrates in situ nanomixing and surface-enhanced Raman scattering readout to enable accurate detection of sE-cadherin and sN-cadherin from as low as 10 cells mL-1 . This assay enables tracking of a concurrent decrease in sE-cadherin and increase in sN-cadherin in breast cancer cells undergoing drug-induced mesenchymal transformation. The clinical potential of the SERS immunoassay is further demonstrated by successful detection of sE-cadherin and sN-cadherin in metastatic stage IV breast cancer patient plasma samples. The SERS immunoassay can potentially sense the activation of EMT to provide early indications of cancer invasions or metastasis.


Subject(s)
Breast Neoplasms , Epithelial-Mesenchymal Transition , Immunoassay , Pharmaceutical Preparations , Spectrum Analysis, Raman , Breast Neoplasms/physiopathology , Cadherins/metabolism , Cell Line, Tumor , Epithelial-Mesenchymal Transition/drug effects , Humans , Microfluidics
9.
Neurosurgery ; 85(4): E641-E649, 2019 10 01.
Article in English | MEDLINE | ID: mdl-31069381

ABSTRACT

BACKGROUND: Fluorescence-guided surgery (FGS) can improve extent of resection in gliomas. Tozuleristide (BLZ-100), a near-infrared imaging agent composed of the peptide chlorotoxin and a near-infrared fluorophore indocyanine green, is a candidate molecule for FGS of glioma and other tumor types. OBJECTIVE: To perform a phase 1 dose-escalation study to characterize the safety, pharmacokinetics, and fluorescence imaging of tozuleristide in adults with suspected glioma. METHODS: Patients received a single intravenous dose of tozuleristide 3 to 29 h before surgery. Fluorescence images of tumor and cavity in Situ before and after resection and of excised tissue ex Vivo were acquired, along with safety and pharmacokinetic measures. RESULTS: A total of 17 subjects received doses between 3 and 30 mg. No dose-limiting toxicity was observed, and no reported adverse events were considered related to tozuleristide. At doses of 9 mg and above, the terminal serum half-life for tozuleristide was approximately 30 min. Fluorescence signal was detected in both high- and low-grade glial tumors, with high-grade tumors generally showing greater fluorescence intensity compared to lower grade tumors. In high-grade tumors, signal intensity increased with increased dose levels of tozuleristide, regardless of the time of dosing relative to surgery. CONCLUSION: These results support the safety of tozuleristide at doses up to 30 mg and suggest that tozuleristide imaging may be useful for FGS of gliomas.


Subject(s)
Brain Neoplasms/diagnostic imaging , Glioma/diagnostic imaging , Indocyanine Green/analogs & derivatives , Neoplasm Recurrence, Local/diagnostic imaging , Optical Imaging/methods , Scorpion Venoms/administration & dosage , Scorpion Venoms/pharmacokinetics , Adult , Aged , Brain Neoplasms/metabolism , Brain Neoplasms/surgery , Dose-Response Relationship, Drug , Female , Fluorescent Dyes/administration & dosage , Fluorescent Dyes/pharmacokinetics , Glioma/metabolism , Glioma/surgery , Humans , Indocyanine Green/administration & dosage , Indocyanine Green/pharmacokinetics , Injections, Intravenous , Male , Middle Aged , Neoplasm Recurrence, Local/metabolism , Neoplasm Recurrence, Local/surgery
10.
J Vis Exp ; (144)2019 02 21.
Article in English | MEDLINE | ID: mdl-30855573

ABSTRACT

Conventional skin biopsy limits the clinical research that involves cosmetically sensitive areas or pediatric applications due to its invasiveness. Here, we describe the protocol for using an absorbent microneedle-based device, absorbent microbiopsy, for minimally invasive sampling of skin and blood mixture. Our goal is to help facilitate rapid progress in clinical research, the establishment of biomarkers for skin disease and reducing the risk for clinical research participants. In contrast to conventional skin biopsy techniques, the absorbent microbiopsy can be performed within seconds and does not require intensive training due to its simple design. In this report, we describe the use of absorbent microbiopsy, including loading and application, on a volunteer. Then, we show how to isolate RNA from the absorbed sample. Finally, we demonstrate the use of quantitative reverse transcription PCR (RT-qPCR) to quantify mRNA expression levels of both blood (CD3E and CD19) and skin (KRT14 and TYR). The methods that we describe utilize off the shelf kits and reagents. This protocol offers a minimally invasive approach for simultaneous sampling of skin and blood within the same absorbent microbiopsy matrix. We have found human ethics committees, clinicians and volunteers to be supportive of this approach to dermatological research.


Subject(s)
Biopsy/methods , RNA/blood , RNA/isolation & purification , Skin/pathology , Specimen Handling/methods , Absorption, Physicochemical , Biomarkers/metabolism , Biopsy/instrumentation , Humans , Male , Needles , RNA/genetics , Specimen Handling/instrumentation , Time Factors
11.
J Colloid Interface Sci ; 537: 536-546, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30469121

ABSTRACT

The colloidal stability of surface-enhanced Raman scattering (SERS) nanotags (Raman reporter-conjugated plasmonic nanoparticles) significantly affects the accuracy and reproducibility of SERS measurements, particularly in biological systems. Limited understanding of SERS nanotag stability may partly hamper the translation of SERS nanotags from the laboratory to their use in the clinic. In this contribution, we utilized differential centrifugal sedimentation (DCS), a reliable and straightforward technique to comprehensively analyze the colloidal stability of SERS nanotags in biological systems. Compared with other particle characterization techniques, DCS has been shown to have a unique advantage for high-resolution and high-throughput polydisperse particle characterization. DCS data revealed that the universal aggregation prevention practice of coating SERS nanotags with silica or bovine serum albumin layers did not sufficiently stabilize them in common measurement environments (e.g., 1 × PBS). Combined DCS and SERS measurements established a strong correlation between the degrees of nanotag aggregation and signal intensities, further reinforcing the necessity of characterizing SERS nanotag stability for every condition in which they are used. We also found that increasing the protein thickness by the inclusion of extra protein components in the detection environments and antibody functionalization can improve the stability of SERS nanotags. We believe that this study can provide guidelines on appropriate measurement techniques and particle design considerations to assess and improve SERS nanotag stability in complex biological systems.


Subject(s)
Benzoates/chemistry , Gold/chemistry , Nanoparticles/chemistry , Spectrum Analysis, Raman , Sulfhydryl Compounds/chemistry , Animals , Cattle , Humans , Particle Size , Serum Albumin, Bovine/chemistry , Silicon Dioxide/chemistry , Surface Properties
12.
Lasers Surg Med ; 50(1): 70-77, 2018 01.
Article in English | MEDLINE | ID: mdl-29193173

ABSTRACT

BACKGROUND: Ablative fractional laser (AFXL) is an acknowledged technique to increase uptake of topical agents in skin. Micro thermal ablation zones (MAZs) consist of ablated vertical channels surrounded by a coagulation zone (CZ). Laser scanning confocal microscopy (LSCM) images individual MAZs at 733 nm (reflectance confocal microscopy (RCM)). Further, LSCM can image sodium fluorescein (NaF) fluorescence with 488 nm excitation (fluorescence confocal microcopy (FCM)), a small hydrophilic test molecule (370 MW, log P -1.52), which may simulate uptake, bio-distribution and kinetics of small hydrophilic drugs. OBJECTIVES: To explore LSCM for combined investigations of CZ thickness and uptake, bio-distribution and kinetics of NaF in AFXL-exposed skin. STUDY DESIGNS/METHODS AND MATERIALS: Excised human abdominal skin samples were exposed to AFXL (15 mJ/microbeam, 2% density) and NaF gel (1000 µg/ml, 10 µl/cm2) in six repetitions, including untreated control samples. CZ thickness and spatiotemporal fluorescence intensities (FI) were quantified up to four hours after NaF application by RCM and FCM. Test sites were scanned to a depth of 200 µm, quantifying thickness of skin compartments (stratum corneum, epidermis, upper dermis), individual CZ thicknesses and FI in CZ and surrounding skin. RESULTS: RCM images established skin morphology to a depth of 200 µm. The CZ thickness measurements were feasible to a depth of 50 µm, and remained unchanged over time at 50 µm (P > 0.5). FI were detected to a depth of 160 µm and remained constant in CZ up to four hours after NaF application (15 minutes: 79 AU (73-92 AU), 60 minutes: 72 AU (58-82 AU), four hours: 78 AU (71-90 AU), P > 0.1). In surrounding skin, FI increased significantly over time, but remained lower than FI in CZ (15 minutes: 21 AU (17-22 AU), 60 minutes: 21 AU (19-26 AU), four hours: 42 (31- 48 AU), P = 0.03). AFXL-processed skin generated higher FI compared to non-laser processed skin in epidermis and upper dermis at 60 minutes and four hours (P = 0.03). CONCLUSIONS: By LSCM, assessment of the AFXL-induced CZ thickness was feasible to a depth of 50 µm, and assessment of FI from a small hydrophilic test molecule, NaF in CZ and surrounding skin feasible to a depth of 160 µm. Lasers Surg. Med. 50:70-77, 2018. © 2017 Wiley Periodicals, Inc.


Subject(s)
Laser Coagulation/methods , Lasers, Solid-State/therapeutic use , Microscopy, Confocal , Skin/diagnostic imaging , Skin/radiation effects , Humans , Proof of Concept Study , Tissue Culture Techniques
13.
PeerJ ; 5: e3631, 2017.
Article in English | MEDLINE | ID: mdl-28852586

ABSTRACT

Identification of appropriate reference genes (RGs) is critical to accurate data interpretation in quantitative real-time PCR (qPCR) experiments. In this study, we have utilised next generation RNA sequencing (RNA-seq) to analyse the transcriptome of a panel of non-melanoma skin cancer lesions, identifying genes that are consistently expressed across all samples. Genes encoding ribosomal proteins were amongst the most stable in this dataset. Validation of this RNA-seq data was examined using qPCR to confirm the suitability of a set of highly stable genes for use as qPCR RGs. These genes will provide a valuable resource for the normalisation of qPCR data for the analysis of non-melanoma skin cancer.

14.
JAMA Dermatol ; 151(4): 417-21, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25607474

ABSTRACT

IMPORTANCE: The BRAF V600E mutation accounts for the majority of BRAF mutations found in cutaneous melanoma and is also commonly found in nevi. We used dermoscopy-targeted sampling and a microbiopsy device coupled with DNA sequence analysis to highlight BRAF V600E heterogeneity within a multicomponent melanocytic proliferation. This sampling technique demonstrates the prospect of in vivo application in a clinical setting. OBSERVATIONS: A man in his 50s with Fitzpatrick skin type II presented with an irregularly pigmented melanocytic lesion on his back that met melanoma-specific dermoscopic criteria, and diagnostic shave excision of the lesion was performed. Histopathologic analysis revealed a melanoma in situ arising in a dysplastic nevus. Dermoscopy-targeted microbiopsy specimens were taken across the lesion, and genotyping was carried out on extracted DNA samples for BRAF and NRAS mutations. The melanoma in situ showed only BRAF wild-type results, while the dysplastic nevus showed both BRAF wild-type and BRAF V600E mutations. Sequencing in all DNA samples revealed NRAS wild-type genotype. CONCLUSIONS AND RELEVANCE: Dermoscopy-targeted sampling and genotyping of a melanoma in situ arising in a dysplastic nevus revealed a phenotype-genotype paradox that confounds the exclusive significance of BRAF and NRAS mutations in melanoma pathogenesis. Further studies are required to investigate the importance of other candidate genes linked to melanomagenesis.


Subject(s)
Dysplastic Nevus Syndrome/genetics , Melanoma/genetics , Proto-Oncogene Proteins B-raf/genetics , Skin Neoplasms/genetics , Dermoscopy/methods , Dysplastic Nevus Syndrome/pathology , Genotype , Humans , Male , Melanoma/pathology , Middle Aged , Mutation , Sequence Analysis, DNA , Skin Neoplasms/pathology
15.
PLoS One ; 9(7): e101956, 2014.
Article in English | MEDLINE | ID: mdl-25033398

ABSTRACT

Peptides and proteins play an important role in skin health and well-being. They are also found to contribute to skin aging and melanogenesis. Microneedles have been shown to substantially enhance skin penetration and may offer an effective means of peptide delivery enhancement. The aim of this investigation was to assess the influence of microneedles on the skin penetration of peptides using fluorescence imaging to determine skin distribution. In particular the effect of peptide chain length (3, 4, 5 amino acid chain length) on passive and MN facilitated skin penetration was investigated. Confocal laser scanning microscopy was used to image fluorescence intensity and the area of penetration of fluorescently tagged peptides. Penetration studies were conducted on excised full thickness human skin in Franz type diffusion cells for 1 and 24 hours. A 2 to 22 fold signal improvement in microneedle enhanced delivery of melanostatin, rigin and pal-KTTKS was observed. To our knowledge this is the first description of microneedle enhanced skin permeation studies on these peptides.


Subject(s)
Cosmetic Techniques , Microinjections/methods , Peptides/administration & dosage , Skin Physiological Phenomena , Surgery, Plastic/methods , Abdominoplasty , Administration, Cutaneous , Drug Delivery Systems/methods , Humans , MSH Release-Inhibiting Hormone/administration & dosage , Microscopy, Confocal , Oligopeptides/administration & dosage , Optical Imaging , Peptides/therapeutic use , Skin
16.
JAMA Dermatol ; 150(10): 1079-82, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24695877

ABSTRACT

IMPORTANCE: Recent advances in targeting BRAFV600E mutations, which occur in roughly 50% of melanomas and 70% of benign nevi, have improved response rates and survival in patients with melanoma. With increased survival, the importance of other comorbidities increases and requires consideration in long-term management. This case report discusses dynamic dermoscopic nevus changes that occur during dabrafenib therapy and offers some conclusions regarding BRAF mutations and the changes. OBSERVATIONS: A man in his 30s had been monitored with whole-body dermoscopy at roughly 7-month intervals as part of a nevus surveillance study. Fourteen months after his initial visit, metastases were found, and the patient entered a clinical trial of dabrafenib with or without trametinib therapy. Continued dermoscopic monitoring for the next 12 months revealed that approximately 50% of the existing acquired melanocytic nevi involuted, while the remaining nevi did not change. Biopsy findings from 1 unchanged and 1 involuted nevus showed BRAF wild type in the unchanged nevus, BRAFV600E mutation in the involuting nevus, and no malignant histopathologic characteristics in either one. CONCLUSIONS AND RELEVANCE: Our observations indicate that a previously suggested hypothesis regarding involuting nevi in BRAF inhibitor therapy is correct: Nevi that involute while a patient is undergoing BRAF V600E inhibitor therapy possess the BRAF V600E mutation, while others that grow or remain unchanged are wild type. However larger-scale trials are required to gather conclusive data and create a more complete clinical picture.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Melanoma/drug therapy , Mutation , Nevus/drug therapy , Proto-Oncogene Proteins B-raf/genetics , Skin Neoplasms/drug therapy , Adult , Dermoscopy , Humans , Imidazoles/administration & dosage , Male , Melanoma/secondary , Nevus/genetics , Nevus/pathology , Oximes/administration & dosage , Pyridones/administration & dosage , Pyrimidinones/administration & dosage , Skin Neoplasms/genetics , Skin Neoplasms/pathology
17.
Adv Healthc Mater ; 3(6): 860-6, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24421280

ABSTRACT

Delivery of therapeutics into skin is hindered by the epidermal barriers. To overcome these barriers for the treatment of skin diseases, a cutaneous delivery method capable of field treatment using silica-elongated microparticles is developed. The microparticles are massaged into the skin using a 3D-printed microtextured applicator resulting in significant field-directed drug delivery enhancement.


Subject(s)
Drug Carriers/chemistry , Microspheres , Skin/metabolism , Administration, Cutaneous , Fluorescein/administration & dosage , Fluorescein/chemistry , Healthy Volunteers , Humans , In Vitro Techniques , Microscopy, Confocal , Silicon Dioxide/chemistry
20.
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