Case report: Iatrogenic tattoos caused by skin marking pen in a postoperative patient.

In this report, a female patient suffering from pigment retention caused by a skin marking pen was elucidated. The patient underwent blepharoplasty 6 months ago and presented with blue-black linear marks at the upper eyelid incision 2 weeks after surgery. Under dermoscopy, scattered pigments were observed to accumulate in the epidermis of the upper eyelid. The patient was diagnosed with iatrogenic tattoo by a surgical marking pen. We chose surgical excision of the skin with the pigmentation. Previous studies have established that the risk of bacterial contamination, contact dermatitis, and allergies may increase with the surgical marking pens, while pigment retention has not yet been mentioned yet. Here, we present a case with a pigment retention in the incision. The selection of the surgical labelling methods and the management of the pigmentation were also addressed. According to our clinical findings, the risk of pigment retention by marking pens needs to be mentioned in the patient's informed consent. Therefore, the practitioner should ensure that the ink is cleaned by the end of each invasive procedure.

RNAi of yellow-y, required for normal cuticle pigmentation, impairs courtship behavior and oviposition in the German cockroach (Blattella germanica).

The insect cuticle plays a key role in maintaining the insect's physiological function and behavior. Herein, the yellow-y protein is required to produce black melanin, and is expressed in a pattern that correlates with the distribution of this pigment. However, yellow-y can also have other functions, for instance, in insect behavior, but not much is known. In this study, we have studied the yellow-y gene in one important model and pest species, namely the German cockroach (Blattella germanica), which is to our knowledge the first time reported. In essence, we identified the yellow-y gene (BgY-y) and characterized its function by using RNA interference (RNAi). Silencing of BgY-y gene led to different developmental abnormalities (body weight and wings) in both genders. Specifically, there was an abundant decrease in melanin, turning the body color in pale yellow and the cuticle softer and more transparent. Interestingly, we also observed that the knockdown of BgY-y impaired the male cockroaches to display a weaker response to female-emitted contact sex pheromones, and also that the oviposition ability was weakened in the RNAi females. This study comprehensively analyzed the biological functions of the yellow-y gene in German cockroaches from the perspectives of development, body color, courtship behavior and oviposition, and as a consequence, this may opens new avenues to explore it as a novel pest control gene.

Extracellular vesicles released by keratinocytes regulate melanosome maturation, melanocyte dendricity, and pigment transfer.

Extracellular vesicles (EVs) facilitate the transfer of proteins, lipids, and genetic material between cells and are recognized as an additional mechanism for sustaining intercellular communication. In the epidermis, the communication between melanocytes and keratinocytes is tightly regulated to warrant skin pigmentation. Melanocytes synthesize the melanin pigment in melanosomes that are transported along the dendrites prior to the transfer of melanin pigment to keratinocytes. EVs secreted by keratinocytes modulate pigmentation in melanocytes [(A. Lo Cicero et al., Nat. Commun. 6, 7506 (2015)]. However, whether EVs secreted by keratinocytes contribute to additional processes essential for melanocyte functions remains elusive. Here, we show that keratinocyte EVs enhance the ability of melanocytes to generate dendrites and mature melanosomes and promote their efficient transfer. Further, keratinocyte EVs carrying Rac1 induce important morphological changes, promote dendrite outgrowth, and potentiate melanin transfer to keratinocytes. Hence, in addition to modulating pigmentation, keratinocytes exploit EVs to control melanocyte plasticity and transfer capacity. These data demonstrate that keratinocyte-derived EVs, by regulating melanocyte functions, are major contributors to cutaneous pigmentation and expand our understanding of the mechanism underlying skin pigmentation via a paracrine EV-mediated communication.

Development of an Undergraduate Cell Biology Laboratory to Assess Pigmentation and Cell Size in a Zebrafish Model of Uveal Melanoma.

This study outlines a 2-week laboratory module for an authentic cell biology undergraduate research experience that uses zebrafish (Danio rerio), a popular model organism for research. Previous research has indicated that course-based undergraduate research experiences such as this one increase student confidence, active learning, and retention. During this research experience, students investigate variations in pigmentation in the caudal fins of wild type (WT) and transgenic fish [Tg(mitfa:GNAQQ209L)]. The transgenic fish express a hyperactive Gα protein, GNAQQ209L, under the melanocyte-specific mitfa promoter, offering insights into uveal melanoma, a common eye cancer. Students specifically analyze the black pigmented cells, melanophores, within the caudal fin. We determined that the transgenic zebrafish have increased pigmentation in their caudal fins, but smaller melanophores. These results suggest there are more melanophores in the Tg(mitfa:GNAQQ209L) fish compared to the WT. Future undergraduate research could investigate these cellular differences. This research experience imparts microscopy and image analysis skills and instills the ability to grapple with large datasets, statistical tests, and data interpretation in alignment with biology education principles. Post-laboratory surveys reveal students attain confidence in the above skills and in handling animals, along with a deeper appreciation for model organism research and its relevance to cancer cell biology.

Successful repigmentation of hypopigmented scars with micropunch grafting with a skin-seeding technique.

Hypopigmented scars are challenging to treat, and the focus for successful treatment is to cause pigment cells to produce more melanin. In this study, we evaluated the repigmentation effects of 0.4 mm motorized-micropunch grafting with skin-seeding for hypopigmented scars. Twenty-one patients with hypopigmented scars on the face and neck that had been resistant to conventional treatment and who had finally undergone micropunch grafting with a skin-seeding technique (SST) were retrospectively reviewed. Repigmentation outcomes were evaluated with global assessment by a physician using a 4-point repigmentation scale. Adverse events were noted. The subjects were followed for a 2-year follow-up period post grafting. All 21 subjects exhibited excellent to complete repigmentation of more than 75% of the hypopigmented scars. More than 90% repigmentation was observed in 17 patients. The mean duration for repigmentation that the subjects were satisfied with was 5.5 months. No adverse effects or recurrence instances were observed. Motorized micropunch grafting is an effective and promising alternative treatment for repigmentation of hypopigmented scars.

Presentations of Cutaneous Disease in Various Skin Pigmentations: Acne Vulgaris - Comedonal Acne.

Description Acne vulgaris is a common inflammatory skin condition of the pilosebaceous unit in adolescents and young adults and is primarily characterized by the presence of open and closed comedones. In patients of various skin pigmentations, skin-colored comedones may be difficult to appreciate and lead to incorrect or delayed diagnosis of acne. To aid in the identification of acne vulgaris in patients of various skin pigmentations, we present comedonal acne in different skin types and commonly encountered differential diagnoses. With its significant volume and burden of disease, acne vulgaris should be correctly identified in various skin pigmentations by primary care clinicians for the initiation of appropriate management.

White horses - non-coding sequences drive premature hair greying and predisposition to melanoma.

The Grey allele in horses is causing premature hair greying and susceptibility to melanoma. The causal mutation is a 4.6 kb tandem duplication in intron 6 of the Syntaxin 17 gene. A recent study demonstrated that the most common allele at the Grey locus (G3) involves three tandem copies of this sequence, whilst a more rare allele (G2) has two tandem copies and the wild-type allele (G1) only one copy. The G3 allele is causing fast greying and high incidence of skin melanoma, whereas the G2 allele is causing slow greying and no obvious increase in melanoma incidence. Further somatic copy number expansion has been documented in melanoma tissue from Grey horses. Functional studies showed that this intronic sequence acts as a weak melanocyte-specific enhancer that becomes substantially stronger by the copy number expansion. The Grey mutation is associated with upregulated expression of both Syntaxin 17 and the neighbouring NR4A3 gene in Grey horse melanomas. It is still an open question which of these genes is most important for the phenotypic effects or if causality is due to the combined effect of upregulation of both genes. Interestingly, RNAseq data in the Human Protein Atlas give support for a possible role of NR4A3 because it is particularly upregulated in human skin cancer, and it belongs to a cluster of genes associated with skin cancer and melanin biosynthesis. The Grey mutation and its association with melanoma provide a possibility to study the path to tumour development in numerous Grey horses carrying exactly the same predisposing mutation.

Determining factors of pulse oximetry accuracy: A literature review.

OBJECTIVE: Identify and reach consensus on the variables that affect the measurement of oxygen saturation using pulse oximetry. METHODS: We applied inclusion and exclusion criteria to select relevant studies in databases such as Ebsco and PubMed. The search strategies, carried out until December 2023, focused on publications that addressed the technology of pulse oximeters and variables that influence their accuracy. We assessed the risk of bias of the included studies and used standardized methods for synthesis of results. RESULTS: 23 studies were included. The synthesis of the results highlighted that equipment with tetrapolar technology showed greater precision in oxygen saturation measurements. Increased skin pigmentation, hemoglobinopathies and high skin temperatures can lead to an overestimation of SpO2, while factors such as low perfusion, cold skin temperature, nail polish or tattoos, hypoxemia, anemia and high altitude training, they may underestimate it. On the other hand, motion artifacts, light pollution, frequency >150 beats per minute, electromagnetic interference and location of the sensor can cause distortion of the photoplethymography signal. CONCLUSIONS: The synthesis of the results highlighted that skin pigmentation and light interference can lead to an overestimation of SpO2, while other factors such as low perfusion and altitude tend to underestimate it. The studies presented variability and heterogeneity in their designs, evidencing limitations in the consistency and precision of the evidence. Despite these limitations, the results underscore the importance of considering multiple variables when interpreting pulse oximetry measurements to ensure their reliability. The findings have significant implications for clinical practice and future research.

A randomised investigation of film-forming silicone gel in superficial partial thickness face and neck burn patients: Indication of improved early scar pigmentation outcomes.

INTRODUCTION: Burns to the face and neck are a source of considerable distress and a challenge to manage with dressings. Further, these often superficial injuries pose a risk of scarring and altered pigmentation. Silicone gels have emerged as a potential solution to the challenges of conservative management for face and neck burn injuries. The aims of this study were to explore the effect of topical silicone compared to routine treatment of conservatively managed burns to the face and neck. METHODS: This single-blind, randomised, controlled trial compared topical silicone film-forming dressing to standard of care for superficial partial thickness burns to the face and neck. Time to healing was the primary outcome and secondary outcomes included: 1) scar assessments (modified Vancouver Scar Scale, Dermalab Combo and Patient and Observer Scar Assessment Scale) at six weeks and three months; and 2) pain intensity scale at wound review appointments. RESULTS: Of the 55 participants in the face/neck study, 34 were male and 21 were female. Median age was 36 years (range from 25 to 47 years). The median time to healing for the silicone group was 9 days (CI 7.6 -10.4) and the control group was 7 days (CI 5.3- 8.7), p = 0.056. Analysis demonstrated significantly reduced pigmentation at six weeks in mVSS scores for the silicone group (Md = 0, IQR = 0) compared to the control group (Md = 0, IQR = 0 - 3), p = 0.043. We found no evidence of differences in reported pain between the groups (Silicone - Md = 1.15, IQR 0.3 - 4.5 vs control group - Md = 1.5, IQR 0.6 - 3.8, z = -0.63, p = 0.53). No other differences were observed, and no adverse events were associated with the topical silicone in the study whereas an infection and a reaction were experienced in the control group. CONCLUSION: Film-forming silicone gel had comparable effects to standard of care emollient on wound healing of superficial partial thickness burns of the face and neck. Silicone treated wounds were associated with a significant improvement in scar pigmentation outcome at six weeks post-burn.

Open-label topical application of tetrahexyldecyl ascorbate and acetyl zingerone containing serum improves the appearance of photoaging and uneven pigmentation.

BACKGROUND: Skin photoaging and uneven pigmentation are common dermatological concerns. Tetrahexyldecyl ascorbate (THDA) and acetyl zingerone (AZ) are potent antioxidants that have been shown to have anti-photoaging and anti-pigmentation effects. THDA is a more stable and penetrable form of vitamin C. AZ is an antioxidant derived from ginger which has clinical evidence for improving photoaging. However, no studies have assessed how they may synergistically act on the skin. AIMS: This study aims to assess whether a serum containing both THDA and AZ can improve photoaging and the appearance of uneven facial pigmentation. PATIENTS/METHODS: This open-label study was conducted on 35 healthy individuals aged 21-55. All subjects were instructed to use three to five drops of the topical serum (Power-C Serum, Image Skincare, Lantana, FL) daily for 12 weeks. Videomicroscopy and high-resolution photography and various skin biophysical measurements were taken at baseline, 1, 4, and 12 weeks. Outcomes included skin tone and pigmentation, transepidermal water loss (TEWL), skin smoothness, firmness, and elasticity. RESULTS: Compared to baseline, the results at 12 weeks revealed significant decreases in skin pigmentation (p < 0.0001), decreased fine lines and wrinkles (p < 0.0001), and increased smoothness (p < 0.0001), firmness (p < 0.0001), and elasticity (p < 0.0001). Additionally, transepidermal water loss was significantly decreased at 4 weeks compared to baseline (p = 0.01), indicating an increased epidermal barrier integrity. CONCLUSIONS: Overall, these findings provide evidence for the combined use of THDA and AZ to address skin photoaging and dyspigmentation changes.

Relationship of skin complexion with gingival tissue color and hyperpigmentation. A multi-ethnic comparative study.

BACKGROUND AND OBJECTIVE: The most frequently seen intra-oral soft tissue is the gingiva. Most often, it is seen as coral-pink tissue that surrounds the neck of the teeth. Gingiva that encircles the tooth necks and covers the alveolar processes of the jaws is an intra-oral tissue that exhibits biomimetic features. The wide range of colors of the gingiva depends on the configuration of gingival vascularity, the degree of epithelial cornification, level of melanogenesis, and the depth of epithelialization. However, the color of the gingiva varies depending on the degree of melanin pigmentation. The current study aimed to identify the different distribution patterns of gingival color and determine the correlation between skin color, gender, and geographical area of origin. MATERIALS AND METHODS: A total of 839 subjects were involved in the study where the gingival color and skin tone were measured using the Dummett-Gupta Oral pigmentation Index (DOPI) combined with VITA VMK MASTER and skin shade method developed by Revlon (USA) and L'Oreal (France) for makeup foundation shades. One investigator was calibrated for the examination of the colors after being tested for normal color vision and color aptitude using the line test. RESULTS: A significant association was found between skin color and gingival pigmentation (χ2 value (6) = 114.48; P = 0.001). It was also found that females (67.1%) significantly had darker gingiva than males (58.3%). The study statistics display that location of the individual was also statistically associated with melanin pigmentation of the gingiva (χ2 value (57) = 559.33; P = 0.001). CONCLUSION: The study concluded that gender, skin color, and individual location are significantly associated with gingival melanin pigmentation.

Dye stability of black cherry plum anthocyanins in the interaction with co-pigments and sucrose sweetener.

In this research, the co-pigmentation reactions between black cherry plum (Prunus cerasifera Ehrh. cv. Pissardii Nigra) anthocyanins and caffeic, gallic, 4-hydroxybenzoic, malic, and tannic acids with different concentrations (0, 120, 240, 480, and 960 mg L-1) at various temperatures (20, 40, 60, 80, and 100°C) were investigated at pH 3.5. The strongest immediate co-pigmentations resulted at 960 mg L-1, being significantly highest using tannic acid at all temperatures. In addition, the anthocyanin stability and the brown polymeric color formation were investigated in the presence of different concentrations of sucrose sweetener (0, 30, and 60%) and different pHs (2 and 3) in the range of 0-60 h. Also, the amount of furfural was measured in the presence of 0% and 30% sucrose concentrations at pH 2 after 20 h at 90°C by HPLC (high-performance liquid chromatography), and the most polymeric color formation was observed in the concentration of 60% sucrose at pH 2 after 60 h.

Genomic insights into shank and eggshell color in Italian local chickens.

Eggshell and shank color in poultry is an intriguing topic of research due to the roles in selection, breed recognition, and environmental adaptation. This study delves into the genomics foundations of shank and eggshell pigmentation in Italian local chickens through genome-wide association studies analysis to uncover the mechanisms governing these phenotypes. To this purpose, 483 animals from 20 local breeds (n = 466) and 2 commercial lines (n = 17) were considered and evaluated for shank and eggshell color. All animals were genotyped using the Affymetrix Axiom 600 K Chicken Genotyping Array. As regards shank color, the most interesting locus was detected on chromosome Z, close to the TYRP1 gene, known to play a key role in avian pigmentation. Additionally, several novel loci and genes associated with shank pigmentation, skin pigmentation, UV protection, and melanocyte regulation were identified (e.g., MTAP, CDKN2A, CDKN2B). In eggshell, fewer significant loci were identified, including SLC7A11 and MITF on chromosomes 4 and 12, respectively, associated with melanocyte processes and pigment synthesis. This comprehensive study shed light on the genetic architecture underlying shank and eggshell color in Italian native chicken breeds, contributing to a better understanding of this phenomenon which plays a role in breed identification and conservation, and has ecological and economic implications.

Investigating the impact of pigmentation variation of breast muscle on growth traits, melanin deposition, and gene expression in Xuefeng black-bone chickens.

The blackness traits, considered an important economic factor in the black-bone chicken industry, still exhibits a common phenomenon of significant difference in blackness of breast muscle. To improve this phenomenon, this study compared growth traits, blackness traits, and transcriptome of breast muscles between the High Blackness Group (H group) and Low Blackness Group (L group) in the Xuefeng black-bone chickens. The results are as follows: 1) There was no significant difference in growth traits between the H group and the L group (P > 0.05). 2) The skin/breast muscle L values in the H group were significantly lower than those in the L group, while the breast muscle melanin content exhibited the opposite trend (P < 0.05). 3) A significant negative correlation was observed between breast muscle melanin content and skin/breast muscle L value (P < 0.05), and skin L value exhibiting a significant positive correlation with breast muscle L value (P < 0.05). 4) The breast muscle transcriptome comparison between the H group and L group revealed 831 and 405 DEGs in female and male chickens, respectively. This included 37 shared DEGs significantly enriched in melanosome, pigment granule, and the melanogenesis pathway. Seven candidate genes (DCT, PMEL, MLANA, TYRP1, OCA2, EDNRB2, and CALML4) may play a crucial role in the melanin production of breast muscle in Xuefeng black-bone chicken. The findings could accelerate the breeding process for achieving desired levels of breast muscle blackness and contribute to the exploration of the mechanisms underlying melanin production in black-bone chickens.

Empowering veterinary clinical diagnosis in industrial poultry production by ambient mass spectrometry and chemiometrics: a new approach for precise poultry farming.

Untargeted metabolomic profiling, by ambient mass spectrometry and chemometric tools, has made a dramatic impact on human disease detection. In a similar vein, this study attempted the translation of this clinical human disease experience to farmed poultry for precise veterinary diagnosis. As a proof of principle, in this diagnostic/prognostic study, direct analysis in real-time high resolution mass spectrometry (DART-HRMS) was used in an untargeted manner to analyze fresh tissues (abdominal fat, leg skin, liver, and leg muscle) of pigmented and non-pigmented broilers to investigate the causes of lack of pigmentation in an industrial poultry farm. Afterwards, statistical analysis was applied to the DART-HRMS data to retrieve the molecular features that codified for 2 broiler groups, that is, properly pigmented and non-pigmented broilers. Higher abundance of oxidized lipids, high abundance of oxidized bile derivatives, and lower levels of tocopherol isomers (Vitamin E) and retinol (Vitamin A) were captured in nonpigmented than in pigmented broilers. In addition, conventional rapid analyses were used: 1) color parameters of the tissues of pigmented and non-pigmented broilers were measured to rationalize the color differences in abdominal fat, leg skin and leg muscle, and 2) macronutrients were determined in broiler leg muscle, to capture a detailed picture of the pathology and exclude other possible causes. In this study, the DART-HRMS system performed well in retrieving valuable chemical information from broilers that explained the differences between the 2 groups of broilers in absorption of xanthophylls and the subsequent lack of proper broiler pigmentation in affected broilers. The results suggest this technology could be useful in providing near real-time feedback to aid in veterinary decision-making in poultry farming.

Role of kinin receptors in skin pigmentation.

Previous studies have shown that all kinin system is constitutively expressed in the normal and inflamed skin, with a potential role in both physiological and pathological processes. However, the understanding regarding the involvement of the kinin system in skin pigmentation and pigmentation disorders remains incomplete. In this context, the present study was designed to determine the role of kinins in the Monobenzone (MBZ)-induced vitiligo-like model. Our findings showed that MBZ induces higher local skin depigmentation in kinin receptors knockout mice (KOB1R, KOB2R and KOB1B2R) than in wild type (WT). Remarkably, lower levels of melanin content and reduced ROS generation were detected in KOB1R and KOB2R mice treated with MBZ. In addition, both KOB1R and KOB2R show increased dermal cell infiltrate in vitiligo-like skin, when compared to WT-MBZ. Additionally, lack of B1R was associated with greater skin accumulation of IL-4, IL-6, and IL-17 by MBZ, while KOB1B2R presented lower levels of TNF and IL-1. Of note, the absence of both kinin B1 and B2 receptors demonstrates a protective effect by preventing the increase in polymorphonuclear and mononuclear cell infiltrations, as well as inflammatory cytokine levels induced by MBZ. In addition, in vitro assays confirm that B1R and B2R agonists increase intracellular melanin synthesis, while bradykinin significantly enhanced extracellular melanin levels and proliferation of B16F10 cells. Our findings highlight that the lack of kinin receptors caused more severe depigmentation in the skin, as well as genetic deletion of both B1/B2 receptors seems to be linked with changes in levels of constitutive melanin levels, suggesting the involvement of kinin system in crucial skin pigmentation pathways.

Uveal melanoma: Current evidence on prognosis, treatment and potential developments.

Uveal Melanoma (UM) is a rare disease, yet it is the most common primary intraocular malignancy in adult patients. Despite continuous advancements and research, the risk of metastasis remains high. It is possible to stratify patients according to their risk of metastases using a variety of known risk factors. Even though there is no gold standard for the prognostication of patients with uveal melanoma, it is becoming increasingly clear that combining histo-pathological, patient-related and molecular prognostic markers allows a more accurate prediction of the metastatic risk than by using one parameter. Primary UM in the eye are treated very effectively with eye-sparing radiation-based techniques or enucleation. However, it is not yet possible to prevent or treat metastases with the current therapeutic options. Nonetheless, the efforts to find new therapeutic targets continue and progress is being made, especially in the field of targeted therapy, as exemplified by the anti-gp100 bispecific molecule Tebentafusp. This review delves into the history of uveal melanoma, its incidence, presentation and diagnosis, the known prognostic factors and the treatment options, both for the primary tumour and for metastases. We show that different populations may have different risks for developing UM, and that each country should evaluate their own patients.

Hydroxychloroquine-induced pigmentation in rheumatic diseases: prevalence, clinical features and influencing factors.

OBJECTIVE: To describe the clinical features of Chinese patients with hydroxychloroquine (HCQ)-induced pigmentation and analyze the potential risk factors associated with HCQ-induced pigmentation. METHODS: A cross-sectional study was conducted over a duration of 7 months, during which patients who had received HCQ treatment for >6 months were included. Data was collected through a structured questionnaire that encompassed demographic and geographic characteristics, information on HCQ and concomitant medication usage, sun exposure characteristics, and hyperpigmentation-related characteristics. Univariate and multivariate analyses were employed to calculate the statistical association between HCQ-induced pigmentation and multiple variables. RESULTS: Out of 316 patients, 83 (26.3%) patients presented hyperpigmentation during HCQ treatment. Hyperpigmentation presented after a median duration of HCQ treatment of 12 months (interquartile range, 6.0 months-30.0 months) with a median cumulative dose of 108 g of HCQ (interquartile range, 36-288 g). The most frequently affected sites of pigmentation were the face (60.2%), lower limbs (36.1%), and hands (20.5%). There was a linear decrease in the incidence of pigmentation with increasing daily sun exposure time (p= 0.030). In the multivariate analysis, variables (cumulative HCQ dose and daily sun exposure time) were included in the final models. The results revealed an independent correlation between HCQ-induced pigmentation and daily sun exposure exceeding 1 h (OR: 0.431; 95%CI: 0.208-0.892; p= 0.023). CONCLUSIONS: The occurrence of HCQ-induced pigmentation is not uncommon, with an incidence rate of 26.3%. Daily sun exposure time exhibited a protective effect against HCQ-induced pigmentation.