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Smoky rubyspot damselflies (Hetaerina titia Drury, 1773) are one of the most commonly encountered odonates along streams and rivers on both slopes of Central America and the Atlantic drainages in the United States and southern Canada. Owing to their highly variable wing pigmentation, they have become a model system for studying sexual selection and interspecific behavioral interference. Here, we sequence and assemble the genome of a female smoky rubyspot. Of the primary assembly (i.e. the principle pseudohaplotype), 98.8% is made up of 12 chromosomal pseudomolecules (2N = 22A + X). There are 75 scaffolds in total, an N50 of 120 Mb, a contig-N50 of 0.64 Mb, and a high arthropod BUSCO score [C: 97.6% (S: 97.3%, D: 0.3%), F: 0.8%, M: 1.6%]. We then compare our assembly to that of the blue-tailed damselfly genome (Ischnura elegans), the most complete damselfly assembly to date, and a recently published assembly for an American rubyspot damselfly (Hetaerina americana). Collectively, these resources make Hetaerina a genome-enabled genus for further studies of the ecological and evolutionary forces shaping biological diversity.

Animal pigment patterns are excellent models to elucidate mechanisms of biological organization. Although theoretical simulations, such as Turing reaction-diffusion systems, recapitulate many animal patterns, they are insufficient to account for those showing a high degree of spatial organization and reproducibility. Here, we study the coat of the African striped mouse (Rhabdomys pumilio) to uncover how periodic stripes form. Combining transcriptomics, mathematical modelling and mouse transgenics, we show that the Wnt modulator Sfrp2 regulates the distribution of hair follicles and establishes an embryonic prepattern that foreshadows pigment stripes. Moreover, by developing in vivo gene editing in striped mice, we find that Sfrp2 knockout is sufficient to alter the stripe pattern. Strikingly, mutants exhibited changes in pigmentation, revealing that Sfrp2 also regulates hair colour. Lastly, through evolutionary analyses, we find that striped mice have evolved lineage-specific changes in regulatory elements surrounding Sfrp2, many of which may be implicated in modulating the expression of this gene. Altogether, our results show that a single factor controls coat pattern formation by acting both as an orienting signalling mechanism and a modulator of pigmentation. More broadly, our work provides insights into how spatial patterns are established in developing embryos and the mechanisms by which phenotypic novelty originates.

Coloration facilitates evolutionary investigations in nature because the interaction between genotype, phenotype and environment is relatively accessible. In a landmark set of studies, Endler addressed this complexity by demonstrating that the evolution of male Trinidadian guppy coloration is shaped by the local balance between selection for mate attractiveness versus crypsis. This became a textbook paradigm for how antagonistic selective pressures may determine evolutionary trajectories in nature. However, recent studies have challenged the generality of this paradigm. Here, we respond to these challenges by reviewing five important yet underappreciated factors that contribute to colour pattern evolution: (i) among-population variation in female preference and correlated variation in male coloration, (ii) differences in how predators versus conspecifics view males, (iii) biased assessment of pigmentary versus structural coloration, (iv) the importance of accounting for multi-species predator communities, and (v) the importance of considering the multivariate genetic architecture and multivariate context of selection and how sexual selection encourages polymorphic divergence. We elaborate these issues using two challenging papers. Our purpose is not to criticize but to point out the potential pitfalls in colour research and to emphasize the depth of consideration necessary for testing evolutionary hypotheses using complex multi-trait phenotypes such as guppy colour patterns.

Temperature affects the distribution and success of Apis mellifera subspecies. To survive high temperatures in their natural habitats, unique adaptive traits have been evolved by various A. mellifera subspecies. A. mellifera jemenitica is a sub-tropical subspecies that is native to the Arabian Peninsula. It is one of the most thermotolerant A. mellifera subspecies and the only subspecies that can successfully survive long summers with daily temperatures exceeding 45°C in the Arabian Peninsula. In hot, dry conditions and short seasons, A. m. jemenitica can successfully establish its colonies. In this article, the different morphological, behavioural and physiological aspects of the thermal adaptation of A. m. jemenitica, which are its size, pigmentation, brood cell size, seasonal cycle, foraging behaviour, heat shock proteins and life genes are discussed. These aspects account for how A. m. jemenitica can withstand and survive the high summer temperatures on the Arabian Peninsula.

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.

Objective This study aimed to identify genes regulated by cyclin dependent kinases 5 (CDK5) that participate in hair pigmentation in mice. Methods The mRNA expression profiles of skin samples from CDK5-knockdown mice were constructed using high-throughput RNA sequencing and compared with those of wild-type mice. Results In total, 8,002 known genes were differentially expressed between CDK5-knockdown and wild-type mice. Of these, 3,658 were upregulated and 4,344 were downregulated in the skin of CDK5-knockdown mice. An additional 318 previously unknown genes were also differentially expressed, with 171 downregulated and 147 upregulated genes in the skin of CDK5-knockdown mice. Of the known genes expressed in mouse skin, 80 were associated with hair color, with 61 showing lower expression and 19 exhibiting higher expression in skin of CDK5-knockdown mice. Importantly, the expression of the tyrosinase-related protein 1 (TYRP1) and the calcium signaling pathway were also found to be regulated by CDK5, suggesting that pigmentation is regulated by CDK5 via the calcium signaling pathway and TYRP1. Conclusion The transcriptome profiles obtained from the skin of CDK5-knockdown mice compared to wild-type mice provide a valuable resource to help understand the mechanism by which CDK5 regulates melanogenesis in mice and other animals.

Abstract In the present study, we characterise a strain isolated from the wastewater aeration lagoon of a sugar processing plant in Schleswig (Northern Germany) by Heinz Schlesner. As a pioneer in planctomycetal research, he isolated numerous strains belonging to the phylum Planctomycetota from aquatic habitats around the world. Phylogenetic analyses show that strain SH412T belongs to the family Planctomycetaceae and shares with 91.6% the highest 16S rRNA gene sequence similarity with Planctopirus limnophila DSM 3776T. Its genome has a length of 7.3 Mb and a G + C content of 63.6%. Optimal growth of strain SH412T occurs at pH 7.0–7.5 and 28 °C with its pigmentation depending on sunlight exposure. Strain SH412T reproduces by polar asymmetric division (“budding”) and forms ovoid cells. The cell size determination was performed using a semi-automatic pipeline, which we first evaluated with the model species P. limnophila and then applied to strain SH412T. Furthermore, the data acquired during time-lapse analyses suggests a lifestyle switch from flagellated daughter cells to non-flagellated mother cells in the subsequent cycle. Based on our data, we suggest that strain SH412T represents a novel species within a novel genus, for which we propose the name Planctoellipticum variicoloris gen. nov., sp. nov., with strain SH412T (= CECT 30430T = STH00996T, the STH number refers to the Jena Microbial Resource Collection JMRC) as the type strain of the new species.

Epidermal melanin unit integrity is crucial for skin homeostasis and pigmentation. Epidermal growth factor (EGF) receptor (EGFR) is a pivotal player in cell growth, wound healing, and maintaining skin homeostasis. However, its influence on skin pigmentation is relatively unexplored. This study investigates the impact and underlying mechanisms of EGFR inhibitors on skin pigmentation. We evaluated EGF and EGFR expression in various skin cells using quantitative real‐time PCR, Western blot, and immunofluorescence. EGF and EGFR were predominantly expressed in epidermal keratinocytes, and treatment with the EGFR tyrosine kinase inhibitors (EGFR‐TKIs) gefitinib and PD153035 significantly increased stem cell factor (SCF) and endothelin‐1 (ET‐1) expression in cultured keratinocytes. Enhanced melanocyte migration and proliferation were observed in co‐culture, as evidenced by time‐lapse live imaging and single‐cell tracking assays. Furthermore, topical application of gefitinib to guinea pig dorsal skin induced increased pigmentation and demonstrated efficacy in mitigating rhododendrol‐induced leukoderma. Suppression of EGF signaling indirectly enhanced skin pigmentation by upregulating SCF and ET‐1 in epidermal keratinocytes. This novel mechanism highlights the pivotal role of EGF signaling in regulating skin pigmentation, and topical EGFR‐TKI therapy at an appropriate dose may be a promising approach for depigmentation disorder management. [ABSTRACT FROM AUTHOR]

Post‐inflammatory hyperpigmentation (PIH) is a hypermelanosis that often occurs secondary to skin irritation or injury, especially in darker skin tones, for which there is currently a lack of effective treatment options. Few preclinical models are available to study PIH. Here, we show that the Yucatan miniature pig consistently develops PIH after skin injuries. Skin wounds were produced on Yucatan pigs by needle punches, full‐thickness excisions, or burns. Wound sites were monitored and photographed regularly. Tissue samples were collected after 24 weeks and processed for histology/immunohistochemistry. Skin pigmentation and histologic changes were quantified by computer‐assisted image analyses. All injury methods resulted in hyperpigmentation. Melanin content at the histologic level was quantified in the larger (burn and excision) wounds, showing a significant increase compared to uninjured skin. Increased melanin was found for both epidermal and dermal regions. Dermal melanin deposits were primarily clustered around the papillary vasculature, and were associated not with melanocytes but with leukocytes. The Yucatan miniature pig model recapitulates key clinical and histologic features of PIH in humans, including skin hyperpigmentation at both gross and histologic levels, and persistence of dermal melanin subsequent to injury. This model could be used to further our understanding of the etiology of PIH, and for new therapy development. [ABSTRACT FROM AUTHOR]

Background: The COVID‐19 pandemic brought about a new normal, necessitating the use of personal protective equipment (PPE) like face shields, surgical masks, gloves, and goggles. However, prolonged mask‐wearing introduced skin‐related issues due to changes in the skin's microenvironment, including increased humidity and temperature, as well as pressure on the skin. These factors led to skin deformation, vascular issues, edema, and inflammation, resulting in discomfort and cosmetic concerns. Clinical reports quickly highlighted the consequences of long‐term mask use, including increased cases of "maskne" (mask‐related acne) or mask‐wearing related disorders such as rosacea flare‐ups, skin‐barrier defects, itching, erythema, redness, hyperpigmentation, and lichenification. Some of these issues, like inflammation, oxidative stress, and poor wound healing, could be directly linked to acne‐related disorders or skin hypoxia. Aim: To address these problems, researchers turned to rutin, a well‐known flavonoid with antioxidant, vasoactive, and anti‐inflammatory properties. However, rutin's poor water solubility presented a challenge for cosmetic formulations. To overcome this limitation, a highly water‐soluble form of rutin was developed, making it suitable for use at higher concentrations. Methods: In vitro and ex vivo tests were conducted, as well as an innovative clinical trial including volunteers wearing surgical masks for at least 2 h, to evaluate the biological activity of this soluble rutin on the main skin concerns associated with mask‐wearing (inflammation, oxidative stress, skin repair, hyperpigmentation, and skin redness). Results: The in vitro results showed that the active ingredient significantly reduced oxidative stress, improved wound healing, and reduced inflammation. In dark skin explants, the active ingredient significantly reduced melanin content, indicating its lightening activity. This effect was confirmed in the clinical study, where brown spots decreased significantly after 4 days of application. Moreover, measurements on volunteers demonstrated a decrease in skin redness and vascularization after the active ingredient application, indicating inflammation and erythema reduction. Volunteers reported improved skin comfort. Conclusion: In summary, the COVID‐19 pandemic led to various skin issues associated with mask‐wearing. A highly soluble form of rutin was developed, which effectively addressed these concerns by reducing inflammation, oxidative stress, and hyperpigmentation while promoting wound healing. This soluble rutin offers a promising solution for the rapid treatment of maskne‐related disorders and other skin problems caused by prolonged mask use. [ABSTRACT FROM AUTHOR]

The yellow gene family plays a crucial role in insect pigmentation. It has potential for use as a visible marker gene in genetic manipulation and transgenic engineering in several model and non‐model insects. Sadly, yellow genes have rarely been identified in Stratiomyidae species and the functions of yellow genes are relatively unknown. In the present study, we first manually annotated and curated 10 yellow genes in the black soldier fly (BSF), Hermetia illucens (Stratiomyidae). Then, the conserved amino acids in the major royal jelly proteins (MRJPs) domain, structural architecture and phylogenetic relationship of yellow genes in BSF were analyzed. We found that the BSF yellow‐y, yellow‐c and yellow‐f genes are expressed at all developmental stages, especially in the prepupal stage. Using the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR‐associated protein 9 (Cas9) system, we successfully disrupted yellow‐y, yellow‐c and yellow‐f in the BSF. Consequently, the mutation of yellow‐y clearly resulted in a pale‐yellow body color in prepupae, pupae and adults, instead of the typical black body color of the wild type. However, the mutation of yellow‐c or yellow‐f genes did not result in any change in color of the insects, when compared with the wild type. Our study indicates that the BSF yellow‐y gene plays a role in body pigmentation, providing an optimal marker gene for the genetic manipulation of BSF. [ABSTRACT FROM AUTHOR]

Background Aims Patients/Methods Results Conclusions 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.This study aims to assess whether a serum containing both THDA and AZ can improve photoaging and the appearance of uneven facial pigmentation.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.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.Overall, these findings provide evidence for the combined use of THDA and AZ to address skin photoaging and dyspigmentation changes. [ABSTRACT FROM AUTHOR]

Background: Previous studies have shown that visible light (VL), especially blue light (BL), could cause significant skin damage. With the emergence of VL protection products, a harmonization of light protection methods has been proposed, but it has not been widely applied in the Chinese population. Objective: Based on this framework, we propose an accurate and simplified method to evaluate the efficacy of BL photoprotection for the Chinese population. Methods: All subjects (n = 30) were irradiated daily using a blue LED light for four consecutive days. Each irradiation dose was 3/4 MPPD (minimum persistent pigmentation darkening). The skin pigmentation parameters, including L*, M, and ITA°, were recorded. We proposed the blue light protection factor (BPF) metric based on the skin pigmentation parameters to evaluate the anti-blue light efficacies of different products. Results: We found that the level of pigmentation rose progressively and linearly as blue light exposure increased. We proposed a metric, BPF, to reflect the anti-blue light efficacy of products based on the linear changes in skin pigment characteristics following daily BL exposure. Moreover, we discovered that the BPF metric could clearly distinguish the anti-blue light efficacies between two products and the control group, suggesting that BPF is an efficient and simple-to-use metric for anti-blue light evaluation. Conclusion: Our study proposed an accurate and simplified method with an easy-to-use metric, BPF, to accurately characterize the anti-blue light efficacies of cosmetic products, providing support for further development of anti-blue light cosmetics. [ABSTRACT FROM AUTHOR]

Background Aims Patients/Methods Results Conclusions Tetrahexydecyl ascorbate (THDA) is a lipophilic precursor to ascorbic acid that may be stabilized by acetyl zingerone (AZ). Studies have shown that the topical application of THDA may have photoprotective effects. Similarly, AZ has been shown to mitigate oxidative and inflammatory stress, thereby improving the appearance of photoaging.To examine the effects of THDA and AZ (THDA‐AZ) on skin photoaging compared to THDA alone.In this double‐blind, randomized controlled trial, healthy individuals aged 30 to 65 were included and 44 participants were randomized to receive either THDA‐AZ (THDA 5% + AZ 1%) or THDA only (THDA 5%) for 8 weeks. Facial photographs were taken at 0, 4, and 8 weeks to analyze wrinkle severity, pigment intensity, and redness intensity. A skin colorimeter was used to assess infraorbital pigmentation and erythema. Self‐perception of skin and tolerability were assessed through questionnaires.Average wrinkle severity was significantly decreased in the THDA‐AZ group at Weeks 4 and 8 by 0.75% (p = 0.023) and 3.72% (p = 0.048), respectively, compared to the THDA group where wrinkle severity at Weeks 4 and 8 was increased by 7.88% and 4.48%, respectively. Facial pigment intensity was significantly decreased in the THDA‐AZ group by 4.10% (p = 0.0002) at Week 8 compared to a 0.69% decrease in the THDA group. Facial redness intensity was decreased in the THDA‐AZ group at Weeks 4 and 8 by 3.73% (p = 0.0162) and 14.25% (p = 0.045), respectively, compared to the THDA group where at Weeks 4 and 8 erythema increased by 27.5% and 8.34%, respectively. There were no significant differences in either group for infraorbital pigmentation or erythema.Daily use of combined THDA and AZ may improve facial wrinkle severity, pigment intensity, and erythema to a greater extent than THDA. While THDA alone increases facial wrinkle severity and erythema, the addition of AZ reduces both. [ABSTRACT FROM AUTHOR]

Melasma is a frequent condition worldwide, and it represents one of the most challenging disorders to treat in cosmetic dermatology. One of the critical factors for treatment prognosis is the assessment of the depth and distribution of pigment within the hyperpigmented area. Nowadays, non‐invasive skin imaging techniques, such as reflectance confocal microscopy (RCM), have been used to estimate pigment distribution and depth within different skin layers. This article aims to provide a systematic review of RCM applications in melasma, providing terminology and investigating characteristics of melasma at baseline and after medical and laser treatment. Our results support the recognition of two main types of melasma, epidermal and mixed type, thanks to the role of RCM in highlighting the precise pigment depth location in the skin non‐invasively. RCM treatment monitoring enables the objectification of pigment variations after treatment and the identification of prognostic factors for different treatment modalities. After the era of the application of RCM as a technique applied strictly to skin cancers, additional cosmetic applications are emerging, such as the application of melasma treatment monitoring. [ABSTRACT FROM AUTHOR]

The study was conducted at Dry Land Agriculture Research Station (DARS), Rangreth, Srinagar, Jammu and Kashmir, India aimed to comprehensively assess 40 genotypes, alongside 5 checks, for Distinctness, Uniformity and Stability (DUS) characterization. Employing an Augmented Block Design in the field in kharif season of April-August, 2022 and a Completely Randomized Design (CRD) in the laboratory from September-March 2023, the genotypes underwent evaluation for 21 DUS traits and 43 morphological, maturity, yield and quality traits. The evaluation followed descriptors specific to rajmash genotypes, utilizing frequency distribution based on "state" and "code" for each trait. The results indicated that majority of genotypes exhibited early flowering (<50 days), with 91% displaying an absence of anthocyanin coloration. Erect plant types were prevalent (51.11%), with 51% and 60% being viny and determinate, respectively. Most genotypes featured medium-sized, light green, ovate leaves (46.66%, 53%, and 22%, respectively). White-colored flowers (48.88%) with striped petal surfaces (57.77%) and medium curvature (40.00%) were predominant. Seed-related traits, such as cordate pod shapes (51%) and concave pod sutures (50%), along with acute pod distal shapes (69%), were observed. Pale green pods (57.77%) and 76% of genotypes exhibiting pod stringiness were noted. Seed shapes were mainly kidney-shaped (60%), and absent pigmentation in pod shells (73%) was observed. Large-sized seeds (40%) with dark red testa color (44%) were common, and seed testa variegation was "absent" in 75.55% of genotypes. [ABSTRACT FROM AUTHOR]

Background and Objective: Skin thermal diffusivity plays a crucial role in various applications, including laser therapy and cryogenic skin cooling.This study investigates the correlation between skin thermal diffusivity and two important skin parameters, melanin content and erythema, in a cohort of 102 participants. Methods: An in‐house developed device based on transient temperature measurement was used to assess thermal diffusivity at different body locations. Melanin content and erythema were measured using a colorimeter. Statistical analysis was performed to examine potential correlations. Results: The results showed that the measured thermal diffusivity values were consistent with previous reports, with variations observed among subjects. No significant correlation was found between thermal diffusivity and melanin content or erythema. This suggests that other factors, such as skin hydration or epidermis thickness, may have a more dominant influence on skin thermal properties. Conlcusion: This research provides valuable insights into the complex interplay between skin thermal properties and physiological parameters, with potential implications for cosmetic and clinical dermatology applications. [ABSTRACT FROM AUTHOR]

Background: Ichthyoses are a heterogeneous group of skin disorders characterized by scaling and erythema. Recognizing the variability of scale and erythema by region and ichthyosis subtype, we developed the Ichthyosis Scoring System (ISS) to quantify severity. We previously found ISS to have high inter‐ and intrarater reliability in evaluating photographic images. To confirm ISS clinical utility, we examined its performance at the 2022 Foundation for Ichthyosis and Related Skin Types conference. Methods: Sixty‐five participants were evaluated by 3 of 9 medical professionals trained to score ichthyosis scale and erythema using ISS. Intrarater and interrater intraclass correlation coefficients (ICC) were analyzed using one‐way and two‐way random effects models, respectively. Results: Intrarater reliability was excellent (ICC = 0.931, 95% CI, 0.921–0.940) for scale and good (ICC = 0.876, 95% CI, 0.853–0.899) for erythema scoring. Compared to photo validation with excellent intrarater reliability ratings for both scale (ICC = 0.956, 95% CI, 0.925–0.974) and erythema (ICC = 0.913, 95% CI, 0.855–0.949), ISS demonstrated equivalent reliability for live use. Overall interrater reliability for 10 body sites showed excellent (ICC >0.9) and good (ICC >0.75) agreement and consistency for both scale and erythema. Palms were an exception, demonstrating moderate (ICC >0.5) interrater agreement and consistency for erythema evaluation. Conclusions: ISS is a reliable measure of global and regional ichthyosis severity during in‐person evaluations. Ease‐of‐use, accessibility, and content validity in both live and photographic evaluation endorse ISS as a standard for ichthyosis severity analysis. [ABSTRACT FROM AUTHOR]

Background: The 1064 nm Q-switched neodymium-doped yttrium aluminum garnet (QS Nd:YAG) laser was developed to treat unwanted pigmentation in the skin such as lentigines caused by photoaging, and tattoos from dye/ink insertion. This laser has also been used for non-ablative epidermal rejuvenation (skin toning). Objective: To evaluate changes in skin tone, skin texture and overall improvement after a series of treatments with the QS Nd:YAG laser. Methods: Participants received seven full-face treatments with M22 or Stellar M22, a 1064 nm QS Nd:YAG laser, at 2-week intervals. The investigators and participants evaluated the improvement in skin tone and texture at 1, 3 and 6 months after the last treatment. Patient satisfaction, patient discomfort, downtime and adverse events were recorded. Histological changes in the treated area were also evaluated. Results: Thirteen women with a median age of 45 years (range, 34–61 years) were included in the study. The majority of the participants (53.9%) had skin type VI. One month after the last treatment session, 38% of participants reported good to very good improvement. This value increased to 100% participant improvement at both the 3-month and 6-month follow-up visits. The reduction in melanin index and the histological analysis demonstrated that the laser procedure contributed to a reduction in epidermal melanin content. Treatments were not associated with high levels of pain or discomfort. The most common immediate post-treatment response was erythema and edema. Most participants were satisfied with the resulting treatment outcome. Conclusion: Skin treatment with the 1064 nm QS Nd:YAG laser module on the M22 and Stellar M22 devices, using a large spot size, low fluence, moderately high repetition rate, improves skin tone and texture in patients with skin types II–VI. [ABSTRACT FROM AUTHOR]

MFSD12 functions as a transmembrane protein required for import of cysteine into melanosomes and lysosomes. The MFSD12 locus has been associated with phenotypic variation in skin color across African, Latin American, and East Asian populations. The frequency of a particular MFSD12 coding variant, rs2240751 (MAF = 0.08), has been reported to correlate with solar radiation and occur at highest frequency in Peruvian (PEL MAF = 0.48) and Han Chinese (CHB MAF = 0.40) populations, suggesting it could be causative for associated phenotypic variation in skin color. We have generated a mouse knock‐in allele, Mfsd12Y182H, to model the human missense p.Tyr182His human variant. We demonstrate that the variant transcript is stably expressed and that agouti mice homozygote for the variant allele are viable with an altered coat color. This in vivo data confirms that the MFSD12 p.Tyr182His variant functions as a hypomorphic allele sufficient to alter mammalian pigmentation. [ABSTRACT FROM AUTHOR]

Giant Congenital Melanocytic Naevi (GCMN) is a very rare condition that mostly occurs due to an oncogenic mutation involving the NRAS (neuroblastoma RAS viral oncogene homologue) gene. GCMNs can be clinically diagnosed due to their typical features, but histopathology confirms the diagnosis. GCMN has a high propensity for transforming into malignant melanoma and leptomeningeal melanocytosis, leading to neurological deficits such as epilepsy and neurofibromatosis. As it is associated with Central Nervous System (CNS) melanosis, Magnetic Resonance Imaging (MRI) of the brain and spine is crucial. Here, three cases are reported of the babies born with GCMN from August 2022 to July 2023 in a tertiary care hospital among a total of 11,915 live births, where the incidence is much higher than found in the literature. Present series describes three cases with GCMN, including clinical features, MRI findings, short-term outcomes, risk factors, and modalities of the management. All three cases showed extensive blackish pigmented patches involving most of the body surface and MRI evidence of Neurocutaneous Melanosis (NCM). The third baby succumbed to death due to fulminant sepsis on day 2 of life. Management of GCMN requires a multimodal approach, including medical, surgical, chemotherapeutic, palliative, and psychological support for patients as well as parents, and follow-up is necessary for the early detection of malignant transformation. Detailed knowledge of this very rare condition may enable us to develop newer treatment modalities to achieve better outcomes in the near future.

The goal of this research was to evaluate the effect of light, temperature, sucrose and PEG on the growth of Fragaria vesca in vitro and the expression of regulatory Myb10, WD40 and enzyme-coding genes CHI, CHS, DFR, EGL, F3H and UFGT, which are essential for anthocyanin biosynthesis. We observed plants’ response to osmotic stress, the decrease in growth and microshoot weight. A change in the expression of the investigated genes was evident under the suboptimal concentration of sucrose. The addition of PEG to the medium caused a decrease in microshoot weight and gene expression. Blue + red lights of the LED lighting system significantly affected microshoot growth in vitro. Red and blue + red + UV lights slightly reduced microshoot weight and caused a reddish colour of petioles, which indicate increased anthocyanin synthesis. Moreover, most of the studied genes’ expression tended to increase when shoots were exposed to blue, blue + red and blue + red + UV lights. A temperature of 15°C (vs 22°C) significantly reduced the mean fresh weight of microshoots while increasing CHI and CHS gene expression and decreasing WD40 gene expression. Exposure to a higher temperature (30°C) induced the vitrification of microshoots, although the fresh weight did not differ from that of the control. Gene expression also depended on the duration of exposure. In the case of CHS, gene expression remained the same or increased after exposure for 1 week and then decreased after exposure for 4 weeks.

Objective This study aimed to explore the effects of different types of xanthophyll extracted from marigold on the growth performance, skin color, and carcass pigmentation. Methods A total of 192 healthy 60-day-old yellow-feathered broilers weighing an average of 1,279±81 g were randomly allocated to 4 groups, each with 6 replicates and 8 broilers. The 4 treatments were as follows: i) CON group, fed with basal diet; ii) LTN group, supplemented with lutein; iii) MDP group, supplemented with monohydroxyl pigment including dehydrated lutein, β-cryptoxanthin, and α-cryptoxanthin; iv) LTN+MDP group, supplemented with lutein and monohydroxyl pigment in proportion to 1:1. The supplementary content of LTN, MDP, and LTN+MDP was 2 g/kg. Skin color was measured after 7, 14, 21, and 28 days of feeding the dietary treatments. The breast, thigh, and abdominal fat of slaughtered chickens were stored in cold storage at 4°C for 24 hours and then the meat color of lightness (L*), redness (a*), and yellowness (b*) values was determined. Results The results showed that all treatments enhanced the yellow scores of subwing skin on day 14, 21, and 28 (p

A critical function of animal coloration is avoiding attack, either by warning predators or reducing detectability. Evolution of these divergent strategies may depend on prey palatability and apparency to predators: conspicuous coloration may be favoured if species are distasteful, or habitats make hiding difficult; by contrast, camouflage may be effective if prey lack defences or environments are visually complex. For insect herbivores, host plants provide both chemical defence and the background against which they are detected or obscured; thus, plant traits may be key to coloration in these foundational terrestrial organisms. We use 1808 species of larval Lepidoptera to explore macroevolution of protective coloration strategy. We find that colour and pattern evolve jointly in caterpillars, similar to an array of species across the animal kingdom, while individual elements of coloration evolve closely with diet ecology. Consistent with key tenets of plant defence and plant-herbivore coevolutionary theory, conspicuous colours are associated with herbaceous host plants-thought to be defended by toxins-while camouflage colours and patterns are associated with woody plants and grasses. Contrary to theory, dietary specialization is not associated with conspicuous coloration. Our results add valuable insights into the evolutionary forces shaping colour and pattern in nature.

IntroductionDaily solar ultraviolet (UV) radiation has an important impact on skin health. Understanding the initial events of the UV-induced response is critical to prevent deleterious conditions. However, studies in human volunteers have ethical, technical, and economic implications that make skin equivalents a valuable platform to investigate mechanisms related to UV exposure to the skin. In vitro human skin equivalents can recreate the structure and function of in vivo human skin and represent a valuable tool for academic and industrial applications. Previous studies have utilised non-pigmented full-thickness or pigmented epidermal skin equivalents to investigate skin responses to UV exposure. However, these do not recapitulate the dermal-epidermal crosstalk and the melanocyte role in photoprotection that occurs in vivo. In addition, the UV radiation used in these studies is generally not physiologically representative of real-world UV exposure.MethodsWell-characterised pigmented and non-pigmented skin equivalents that contain human dermal fibroblasts, endogenous secreted extracellular matrix proteins (ECM) and a well-differentiated and stratified epidermis have been developed. These constructs were exposed to UV radiation for ×5 consecutive days with a physiologically relevant UV dose and subsequently analysed using appropriate end-points to ascertain photodamage to the skin.ResultsWe have described that repeated irradiation of full-thickness human skin equivalents in a controlled laboratory environment can recreate UV-associated responses in vitro, mirroring those found in photoexposed native human skin: morphological damage, tanning, alterations in epidermal apoptosis, DNA lesions, proliferation, inflammatory response, and ECM-remodelling.DiscussionWe have found a differential response when using the same UV doses in non-pigmented and pigmented full-thickness skin equivalents, emphasising the role of melanocytes in photoprotection.

Objectives: Gingival pigmentation, the most common etiological factor of which is smoking, is a clinical condition that causes aesthetic complaints. Due to the dose-dependent effect of smoking, gingival pigmentation may present regression following cessation. This cross-sectional study aimed to evaluate gingival pigmentation in former tobacco consumers and compare with current ones. Material and Methods: A total of 110 people, 70 of whom were current smokers (Group CS) and 40 of whom were former smokers (Group FS), were included in the study. Participants filled out the data collection forms containing questions on demographic features and information related to tobacco consumption. In addition, all individuals were examined with Hedin’s melanin index (HMI) to evaluate gingival pigmentation. Statistical significance was set at the P < 0.05 level. Results: The population consisted of 57.3% male, and the mean age of all participants was 39.43 (SD 12.3) years. The mean duration of tobacco consumption did not differ between groups, whereas the mean HMI score of Group FS was significantly lower (P = 0.001). The correlation analyses showed that while the HMI score of Group CS was in relation to both daily consumption amount and duration of consumption (for both, P < 0.01), the HMI score of Group FS showed a negative association with only time elapsed after cessation (P = 0.000). Conclusions: Considering the limitations of this study, the outcomes revealed a dose- and a time-dependent relation of gingival pigmentation in smokers. However, gingival pigmentation in former tobacco consumers was negatively correlated only with time elapsed after cessation.

Carbon baby syndrome also known as universal acquired melanosis is one of the rare causes of diffuse and progressive hyperpigmentation of the skin. A case of a 9-year-old Nepali child was reported in whom darkening of the skin began at the age of 5 months. At presentation, generalized hyperpigmentation was observed with characteristic sparing of pressure areas over the palms and soles. The diagnosis was established by histopathological evidence of epidermal and dermal melanization after the exclusion of all cutaneous and systemic causes for such hyperpigmentation. This case is reported for its rarity and unusual clinicohistopathological features.

Giant Congenital Melanocytic Naevi (GCMN) is a very rare condition that mostly occurs due to an oncogenic mutation involving the NRAS (neuroblastoma RAS viral oncogene homologue) gene. GCMNs can be clinically diagnosed due to their typical features, but histopathology confirms the diagnosis. GCMN has a high propensity for transforming into malignant melanoma and leptomeningeal melanocytosis, leading to neurological deficits such as epilepsy and neurofibromatosis. As it is associated with Central Nervous System (CNS) melanosis, Magnetic Resonance Imaging (MRI) of the brain and spine is crucial. Here, three cases are reported of the babies born with GCMN from August 2022 to July 2023 in a tertiary care hospital among a total of 11,915 live births, where the incidence is much higher than found in the literature. Present series describes three cases with GCMN, including clinical features, MRI findings, short-term outcomes, risk factors, and modalities of the management. All three cases showed extensive blackish pigmented patches involving most of the body surface and MRI evidence of Neurocutaneous Melanosis (NCM). The third baby succumbed to death due to fulminant sepsis on day 2 of life. Management of GCMN requires a multimodal approach, including medical, surgical, chemotherapeutic, palliative, and psychological support for patients as well as parents, and follow-up is necessary for the early detection of malignant transformation. Detailed knowledge of this very rare condition may enable us to develop newer treatment modalities to achieve better outcomes in the near future. [ABSTRACT FROM AUTHOR]

Temperature affects the distribution and success of Apis mellifera subspecies. To survive high temperatures in their natural habitats, unique adaptive traits have been evolved by various A. mellifera subspecies. A. mellifera jemenitica is a sub-tropical subspecies that is native to the Arabian Peninsula. It is one of the most thermotolerant A. mellifera subspecies and the only subspecies that can successfully survive long summers with daily temperatures exceeding 45°C in the Arabian Peninsula. In hot, dry conditions and short seasons, A. m. jemenitica can successfully establish its colonies. In this article, the different morphological, behavioural and physiological aspects of the thermal adaptation of A. m. jemenitica, which are its size, pigmentation, brood cell size, seasonal cycle, foraging behaviour, heat shock proteins and life genes are discussed. These aspects account for how A. m. jemenitica can withstand and survive the high summer temperatures on the Arabian Peninsula. [ABSTRACT FROM AUTHOR]

Background: Ocular melanocytosis was originally described as pigmentary glaucoma and reported in seven dogs of the Cairn Terrier breed. Subsequently, the occurrence of this condition was reported in other breeds of dogs among them a Shih Tzu, recently described. With progression, black pigment spots in the sclera and episclera cover the ciliary cleft. Pigment particles can often be seen suspended in the aqueous and, as they sediment, cover the ventral drainage angle, causing secondary glaucoma. The aim of this study was to describe the clinical and sonographic findings of a Shih Tzu dog with melanocytosis and unilateral secondary glaucoma. Case: A 8-year-old, male, Shih Tzu dog, with a history of progressive darkening of the sclera for 5 years, was referred to the ophthalmological service. The patient underwent routine ophthalmic examination. Slit lamp biomicroscopy revealed anisocoria. In the right eye, diffuse pigmentation of the sclera was observed in almost the entire perilimbal region, and in the iris signs of advanced atrophy with tissue loss between 9 h and 12 h. Nevertheless, zonular ligaments could be observed in this region, as well as a large amount of pigment deposits in the ventral region of the ciliary cleft. Applanation tonometry showed intraocular pressure (IOP) of 14 mmHg. Fundoscopic examination did not reveal abnormal pigmentation, but attenuation of the retinal vessels and in the optic disc was observed. In the left eye, no change was observed to demonstrate the bilaterality of the disease. One month later, the patient returned to the ophthalmology service complaining of an increase in the size of the right eye. Ophthalmic examination revealed moderate buftalmia in the right eye, IOP of 30 mmHg and increased ocular melanosis. Treatment was instituted to control intraocular pressure. Fifteen days after the start of treatment, the IOP decreased to 18 mmHg and it was found that the ophthalmic signs had improved, with a decrease in ocular discomfort. Ultrasound examination showed an increase in the anteroposterior axis and expansion of the anterior chamber, with scattered hyperechogenic spots in the periphery. Ultrasound biomicroscopy (UBM) was performed, in which the presence of obstruction in the ciliary fissure and the presence of punctate echoes between the ciliary fissure and the iris were observed. Four months later, the ophthalmic signs were stable, as well as the IOP (20 mmHg). Currently, the animal is visual in both eyes and with a stable condition in the progression of the disease. Discussion: This condition also known as melanocytosis, pigmentary glaucoma or abnormal pigment deposition, involves the gradual accumulation of pigment-laden cells mainly, melanocytes but also melanophages, in the anterior segment structures including the iris and ciliary body. It is seen in dogs of the Cairn Terriers breed as a hereditary defect, but has been reported in other breeds. Recently the condition was reported in a Shih Tzu, however differently from our work where the condition was unilateral and with a controllable glaucoma. The disorder initially manifests clinically with a progressive bilateral dark peripheral thickening of the iris base, followed by scleral/episcleral plaques of pigment adjacent to the limbus. Signs increase slowly, with pigment clusters in the aqueous and pigmentation in the ventral iridocorneal angle and peripheral endothelium, symptoms are usually bilateral, although not always symmetrical. This is the 1st case of a Shih Tzu with melanocytosis and controlled secondary glaucoma, unilateral, reported in the literature. This is a disease that should be considered as a differential diagnosis of uveal melanomas and melanocytomas. [ABSTRACT FROM AUTHOR]

Karakul (KAR) is one of the resistant sheep breeds to harsh desert conditions, which is also known for its excelent lamb pelt quality. This study was performed to identify the signature of selections in the KAR breed using whole-genome sequencing data (WGS) compared with five other Iranian native sheep. Three methods, including population differentiation index (Fst), nucleotide diversity (π), and cross-population extended haplotype homozygosity (XP-EHH) applied to detect the genomic signature of selection. Data analysis leads to identifying 38 shared genes among three methods as positively selected genes for the KAR breed. The most of mentioned genes were associated with coat color (KIT, DVL3, YPEL3, ERBB4, ZNF451, and CTSO), fat and energy metabolism (GDPD3, STARD13, ZNF106, MAPK3, RGS6, PHYH, AP2M1, SPAG9, DNAH9, NDUFAF6, and ARSK), muscle function (MYOCD and MCTP1), growth (CPNE4), altitude adaptation (DNAH9 and SERGEF), and reproduction (TBX6, PHYH, SPAG9, and ARSK). Based on our results, these candidate genes may have a positive effect on the adaptation of the KAR breed to a desert environment. [ABSTRACT FROM AUTHOR]

Background: Long wavelength ultraviolet‐A1 in combination with visible light induces hyperpigmentation, particularly in dark‐skin phototypes. This study evaluated the efficacy of four sunscreen formulations in protecting against VL + UVA1 (370–700 nm). Methods: The test products (A–D) were applied to the back of 12 volunteers, then irradiated with 320 J/cm2 VL + UVA1 (3.5% UVA1 [370–400 nm]). Immediately after irradiation, and at Days 1, 7, and 14, erythema and pigmentation were assessed by investigator global assessment (IGA), colorimetry (Δa* and ΔITA) and diffuse reflectance spectroscopy (DRS)‐measured relative dyschromia (area under the curve AUC). Control areas were irradiated without sunscreen. Results: Product D, containing titanium dioxide 11%, iron oxides 1%, and antioxidants, provided the highest and most consistent protection. Compared with unprotected irradiated control, it had statistically significantly less erythema on IGA, DRS (Δoxyhemoglobin), and colorimetry (Δa*) at Day 0; less pigmentation on IGA at all time points, on DRS (relative dyschromia) at Days 7 and 14, and on colorimetry (ΔITA) at Day 0. Product B, containing zinc oxide 12% plus organic UV filters, iron oxides 4%, and antioxidants, also showed some efficacy. Conclusion: Of the sunscreens tested, the tinted products provided better protection against VL + UVA1 than the non‐tinted products. Since the product with 1% iron oxides was superior to the product with 4% iron oxides, further studies are needed to evaluate whether iron oxide content correlates with better protection. [ABSTRACT FROM AUTHOR]

The influence of feeding Atlantic salmon for 90 days on diets that excluded fishmeal (FM) and fish oil (FO) was examined for influence on various quality traits. In addition, the effect of adding krill meal (KM; 0%, 2.5%, and 5%), as a putative feed palatant was also examined. Total replacement of FM/FO had a limited effect on production characteristics, affecting percentage yields of headed and gutted control fish and their standard length (p < 0.05). Variances between dietary groups were observed for pigmentation, and plant protein-based KM-free-fed fish returned deeper hues across their belly, NQC (Norwegian Quality Cut), and back portions (p < 0.03). No differences were measured for relative fin condition. δ13C and δ15N concentrations were lower and higher, respectively (p < 0.05) for fish fed the FM/FO-based diet. δ13C:δ15N likewise differed between treatments with FM/FO-fed salmon expressing higher ratios. Fillet mechanical characteristics varied with fish fed on animal protein-based diets, without KM expressing higher springiness and resilience (p < 0.05). Fish fed plant-based diets were generally preferred by younger taste testers. The results from this trial illustrate that FM/FO can be completely removed from salmon diets without problematic effects on quality and palatability attributes. [ABSTRACT FROM AUTHOR]

The US standard for maize commercially grown for grain specifies that yellow corn can contain at maximum 5% corn of other colors. Inbred parents of commercial hybrids typically have clear pericarp, but transgressive segregants in breeding populations can display variation in pericarp pigmentation. We identified 10 doubled haploid biparental populations segregating for pigmented pericarp and evaluated qualitative genetic models using chi-square tests of observed and expected frequencies. Pigmentation ranged from light to dark brown color, and pigmentation intensity was quantitatively measured across 1,327 inbred lines using hue calculated from RGB pixel values. Genetic mapping was used to identify loci associated with pigmentation intensity. For 9 populations, pigmentation inheritance best fit a hypothesis of a 2- or 3-gene epistatic model. Significant differences in pigment intensity were observed across populations. W606S-derived inbred lines with the darkest pericarp often had clear glumes, suggesting the presence of a novel P1-rw allele, a hypothesis supported by a significant quantitative trait locus peak at P1. A separate quantitative trait locus region on chromosome 2 between 221.64 and 226.66 Mbp was identified in LH82-derived populations, and the peak near p1 was absent. A genome-wide association study using 416 inbred lines from the Wisconsin Diversity panel with full genome resequencing revealed 4 significant associations including the region near P1. This study supports that pericarp pigmentation among dent maize inbreds can arise by transgressive segregation when pigmentation in the parental generation is absent and is partially explained by functional allelic variation at the P1 locus. [ABSTRACT FROM AUTHOR]

Melanoma accounts for the majority of skin cancer‐related mortality, highlighting the need to better understand melanoma initiation and progression. In‐depth molecular analysis of neoplastic melanocytes in whole tissue biopsies may be diluted by inflammatory infiltration, which may obscure gene signatures specific to neoplastic cells. Thus, a method is needed to precisely uncover molecular changes specific to tumor cells from a limited sample of primary melanomas. Here, we performed laser capture microdissection (LCM) and gene expression profiling of patient‐derived frozen sections of pigmented lesions and primary cutaneous melanoma. Compared to bulk tissue analysis, analysis of LCM‐derived samples identified 9528 additional differentially expressed genes (DEGs) including melanocyte‐specific genes like PMEL and TYR, with enriched of pathways related to cell proliferation. LCM methodology also identified potentially targetable kinases specific to melanoma cells that were not detected by bulk tissue analysis. Taken together, our data demonstrate that there are marked differences in gene expression profiles depending on the method of sample isolation. We found that LCM captured higher expression of melanoma‐related genes while whole tissue biopsy identified a wider range of inflammatory markers. Taken together, our data demonstrate that LCM is a valid approach to identify melanoma‐specific changes using a relatively small amount of primary patient‐derived melanoma sample. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study is to determine the prevalence of oral pigmentation caused by Zidovudine in individuals with HIV infection in the Kodagu region of India. Methods: The study included a total of 91 HIV-infected individuals who were undergoing treatment with Zidovudine. Thorough muco-cutaneous examinations were conducted to assess the presence of oral pigmentation. The location of the pigmented lesions, the duration since their appearance, and the duration of treatment were carefully documented. Subsequently, all the collected data were recorded and subjected to statistical analysis. Results: Out of the 91 subjects receiving Zidovudine, 48 (52.7%) exhibited oral mucosal pigmentation, and 8 (8.8%) showed both intraoral and extraoral pigmentation. The most commonly affected intraoral sites were the buccal mucosa (47.3%), hard palate (30.8%), tongue (16.5%), gingiva (7.7%), lower alveolar ridge (3.3%), and upper alveolar ridge (1.1%). Additionally, 8 subjects (8.8%) exhibited pigmentation along the face and nails. Notably, 84.9% of individuals had been on Zidovudine for more than 5 years. Conclusion: Prolonged treatment with Zidovudine is known to cause oral hyperpigmentation, which is a significant side effect. By providing prior explanations about the potential adverse reactions associated with the antiviral drug regimen, adherence to the treatment can be improved. [ABSTRACT FROM AUTHOR]

The identification of candidate genes related to pigmentation and under selective sweep provides insights into the genetic basis of pigmentation and the evolutionary forces that have shaped this variation. The selective sweep events in the genes responsible for normal coat color in Indian cattle groups are still unknown. To find coat color genes displaying signs of selective sweeps in the indigenous cattle, we compiled a list of candidate genes previously investigated for their association with coat color and pigmentation. After that, we performed a genome-wide scan of positive selection signatures using the BovineSNP50K Bead Chip in 187 individuals of seven indigenous breeds. We applied a wide range of methods to find evidence of selection, such as Tajima's D, CLR, iHS, varLD, ROH, and FST. We found a total of sixteen genes under selective sweep, that were involved in coat color and pigmentation physiology. These genes are CRIM1 in Gir, MC1R in Sahiwal, MYO5A, PMEL and POMC in Tharparkar, TYRP1, ERBB2, and ASIP in Red Sindhi, MITF, LOC789175, PAX3 and TYR in Ongole, and IRF2, SDR165 and, KIT in Nelore, ADAMTS19 in Hariana. These genes are related to melanin synthesis, the biology of melanocytes and melanosomes, and the migration and survival of melanocytes during development. [ABSTRACT FROM AUTHOR]

Although neuromelanin is a dark pigment characteristic of dopaminergic neurons in the human substantia nigra pars compacta, its potential role in the pathogenesis of Parkinson's disease (PD) has often been neglected since most commonly used laboratory animals lack neuromelanin. Here we took advantage of adeno-associated viral vectors encoding the human tyrosinase gene for triggering a time-dependent neuromelanin accumulation within substantia nigra pars compacta dopaminergic neurons in macaques up to similar levels of pigmentation as observed in elderly humans. Furthermore, neuromelanin accumulation induced an endogenous synucleinopathy mimicking intracellular inclusions typically observed in PD together with a progressive degeneration of neuromelanin-expressing dopaminergic neurons. Moreover, Lewy body-like intracellular inclusions were observed in cortical areas of the frontal lobe receiving dopaminergic innervation, supporting a circuit-specific anterograde spread of endogenous synucleinopathy by permissive trans-synaptic templating. In summary, the conducted strategy resulted in the development and characterization of a new macaque model of PD matching the known neuropathology of this disorder with unprecedented accuracy. Most importantly, evidence is provided showing that intracellular aggregation of endogenous α-synuclein is triggered by neuromelanin accumulation, therefore any therapeutic approach intended to decrease neuromelanin levels may provide appealing choices for the successful implementation of novel PD therapeutics. [ABSTRACT FROM AUTHOR]

Discus (Symphysodon spp.) is a popular freshwater ornamental fish with high market value due to its extraordinary skin pigmentation. The molecular mechanisms that govern skin colouration have yet to be identified. Six skin samples from wild discus were collected in the D1 (dorsal intense black bar stripe), D2 (ventral lighter bar stripes and orange carotenoid spots) and D3 (posterior without stripe nor spot) regions of wild discus for transcriptomic profiling and analysis. Differential analysis was conducted in 3 pair-wise comparisons, D1vsD3, D2vsD3 and D2vsD1. The results demonstrated that the melanin synthesis-associated genes (ERBB4, ADCY9, WNT2, 14-3-3 proteins and TSPAN genes) were upregulated in D1 and D2 regions, whereas carotenoids metabolism-associated genes (PLIN2, AHCY, RETSAT, STARD10, TTC39B and RDH1 genes) were uniquely expressed in D2 region. Amino acid metabolism-related pathways were enriched in both the D1 and D2 regions. MAPK pathway enrichment was detected merely in the D1 region, while various transporter activities were enriched in the D2 region. Further investigations speculated the key regulator roles of GNAQ, ADCY9, 14-3-3 and TSPAN genes in black vertical bar formation. This is the first fundamental report on discus skin pigment genes that could be extended into more detailed studies in the future. [ABSTRACT FROM AUTHOR]

Background: To determine the composition of skin pigmentation in chronic venous insufficiency (CVI) and other less common vascular conditions of lower limbs. Methods: Forty-five skin biopsies were obtained from 17 patients. Samples were taken from pigmented regions and compared with control non-lesional samples from the same patient. Perl's Prussian Blue was used to identify haemosiderin and Schmorl's for melanin. Results: Seven patients presented with CVI, one with concurrent livedo vasculopathy (LV). One patient had LV only. Two patients had acroangiodermatitis (AAD). Six patients had post-sclerotherapy pigmentation (PSP), one with concurrent post-inflammatory hyperpigmentation (PIH). One patient had PIH only. The predominant pigment in CVI samples was haemosiderin. C5-C6 patients showed increased epidermal melanin. LV, AAD, and PSP samples showed dermal haemosiderin but no increase in epidermal melanin. PIH samples showed prominent epidermal melanin whilst no haemosiderin was detected. Conclusion: The predominant pigment in CVI and other vascular conditions was haemosiderin. Melanin was present in later stages of CVI (C5-C6) and in PIH. [ABSTRACT FROM AUTHOR]

Phenotypic sexual dimorphism often involves the hormonal regulation of sex-biased expression for underlying genes. However, it is generally unknown whether the evolution of hormonally mediated sexual dimorphism occurs through upstream changes in tissue sensitivity to hormone signals, downstream changes in responsiveness of target genes, or both. Here, we use comparative transcriptomics to explore these possibilities in 2 species of Sceloporus lizards exhibiting different patterns of sexual dichromatism. Sexually dimorphic S. undulatus develops blue and black ventral coloration in response to testosterone, while sexually monomorphic S. virgatus does not, despite exhibiting similar sex differences in circulating testosterone levels. We administered testosterone implants to juveniles of each species and used RNAseq to quantify gene expression in ventral skin. Transcriptome-wide responses to testosterone were stronger in S. undulatus than in S. virgatus , suggesting species differences in tissue sensitivity to this hormone signal. Species differences in the expression of genes for androgen metabolism and sex hormone-binding globulin were consistent with this idea, but expression of the androgen receptor gene was higher in S. virgatus , complicating this interpretation. Downstream of androgen signaling, we found clear species differences in hormonal responsiveness of genes related to melanin synthesis, which were upregulated by testosterone in S. undulatus , but not in S. virgatus. Collectively, our results indicate that hormonal regulation of melanin synthesis pathways contributes to the development of sexual dimorphism in S. undulatus , and that changes in the hormonal responsiveness of these genes in S. virgatus contribute to the evolutionary loss of ventral coloration. [ABSTRACT FROM AUTHOR]

Splashed white in horses is characterized by extensive white patterning on the legs, face and abdomen and may be accompanied by deafness. To date, seven variants in microphthalmia‐associated transcription factor (MITF) and two variants in Paired Box 3 (PAX3) have been identified to explain this phenotype. A splashed white Thoroughbred stallion, whose sire and dam were not patterned, was hypothesized to have a de novo variant leading to his white coat pattern. A whole‐genome sequencing candidate gene approach identified two single nucleotide variants (SNVs) in SOX10, four SNVs in MITF and a 2.3 kb deletion in MITF with the alternative allele present in this stallion but absent in the other 18 horses analyzed. All six SNVs were annotated as modifiers and were not further considered. The deletion in MITF (NC_009159.3:g.21555811_21558139delinsAAAT) encompasses exon 9 encoding a part of the helix–loop–helix domain required for DNA binding. Sanger sequencing and parentage testing confirmed that this deletion was a de novo mutation of maternal origin. Consistent with the published nomenclature, we denote this likely causal variant as SW8. Genotyping three of this stallion's offspring identified SW8 only in the nearly all‐white foal that was confirmed deaf by brainstem auditory evoked response testing. This foal was also a compound heterozygote for dominant white variants (W20/W22), but to date, W variants alone have not been connected to deafness. SW8 marks the fourth de novo MITF variant in horses reported to cause white patterning. The link between deafness and all MITF variants with and without other variants impacting melanocyte development and function needs to be further explored. [ABSTRACT FROM AUTHOR]

Background: Hyperpigmented scars, particularly in exposed body areas, can be difficult to conceal and may evoke psychological distress. While the precise causes of scar dyschromia are not fully understood, alterations in melanogenic activity appear to hold more significance than changes in melanocyte quantity. Current treatments encompass laser interventions. However, it is essential to consider their costs and potential complications in relation to their limited proven effectiveness. Fat grafting has gained interest as a scar modulation technique due to its regenerative properties, and its efficacy in reducing scar hyperpigmentation is currently under investigation. Methods: A systematic review and meta-analysis was reported according to PRISMA guidelines. PubMed, Embase, and Cochrane Library databases were accessed. PROSPERO registration number is CRD42023457778. The primary outcome was a change in scar pigmentation after fat grafting. Pigmentation changes after fat grafting were calculated using the standardized mean difference (SMD) between baseline and postoperative scores according to POSAS and VSS scales. Bias assessment was conducted according to the National Institute for Health and Clinical Excellence quality assessment tool. Results: A total of 8 articles meeting inclusion and exclusion criteria were identified, involving 323 patients with hyperpigmented scars treated with fat grafting. A significant difference in scar pigmentation was noted after treatment with fat grafting according to observers' ratings, with a SMD of − 1.09 [95% CI: − 1.32; − 0.85], p<0.01. The SMD for patient-reported scar pigmentation after treatment with fat grafting was − 0.99 [96% CI: − 1.31; − 0.66], p<0.01. Four studies provided objective measurements of melanin changes after fat grafting and revealed inconsistent findings compared to subjective observations. Conclusions: Fat grafting shows promise in ameliorating hyperpigmented scars based on subjective assessments, but further corroborating evidence from objective measures is required. Level of Evidence IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266. [ABSTRACT FROM AUTHOR]

Vitiligo is a chronic skin disorder characterized by the loss of pigmentation, resulting in white patches on the skin. The condition arises from the destruction of melanocytes, the cells responsible for producing melanin, the pigment that gives colour to the skin, hair, and eyes. Although the exact etiology of vitiligo remains elusive, it is believed to involve a complex interplay of genetic, autoimmune, and environmental factors. This overview provides the key aspects of vitiligo, including its epidemiology, pathogenesis, clinical manifestations, and current treatment approaches. The prevalence of vitiligo varies globally, affecting individuals of all ethnic backgrounds and age groups. The autoimmune hypothesis proposes that the immune system mistakenly targets and attacks melanocytes, leading to their destruction. Triggering factors, such as oxidative stress, viral infections, and neural factors, may contribute to the initiation and progression of vitiligo. Clinically, vitiligo can significantly impact the quality of life for affected individuals, both psychologically and socially. The distribution and extent of involvement vary, and the condition can affect any part of the body. Various treatment modalities are available for vitiligo, ranging from topical corticosteroids and calcineurin inhibitors to phototherapy and surgical interventions. While these approaches may help to re-pigment the skin to some extent, there is no definitive cure, and the outcomes can be unpredictable. Ongoing research is focused on understanding the molecular mechanisms underlying vitiligo and developing targeted therapies to address the root causes of the disease. [ABSTRACT FROM AUTHOR]

Researchers and consumers are highly interested in wild edible fruits around the world. Prunus jenkinsii grows in the wild and produces edible fruits, substantially contributing to the health, food, and livelihood of the people living in the eastern Himalayas, India. Although this species is extremely valuable, research on it is negligible. In this study, we investigated the changes in biochemical and functional properties at four different stages of fruit growth, including the immature, mature, ripe, and over-ripe stages, and determined the best stages for harvesting. Our findings showed that the fruit at the ripe stage had the highest fruit weight (6.57 ± 0.04 g), pulp content (43.33 ± 1.34%), total soluble solids (15.04 ± 1.14 °Brix), carbohydrate content (34.74 ± 0.08 mg glucose/g fw), phenols (552.41 ± 11.63 mg GAE/100 g fw), flavonoids (153.81 ± 3.44 mg QE/100 g fw), anthocyanins (313.03 ± 11.79 mg cyd-3-glu eq./100 g fw), and FRAP value (1374.54 ± 92.47 mM FeSO4 eq./100 g fw). These characteristics and their corresponding values increased from the immature stage to the ripe stage; then, they decreased in the over-ripe stage. The number of fruits, firmness, acidity, and ascorbic acid content decreased after ripening. The a* value of the peel changed abruptly from green colour (a*, − 9.44 ± 0.59) at the immature stage to red at the mature stage (a*, 3.13 ± 1.03), and then, to reddish-purple (a*, 5.36 ± 0.76 and b* value, − 1.82 ± 0.30) at the ripe stage and dark purple at the over-ripe stage. Therefore, the stages of fruit maturity strongly influenced the biochemical and antioxidant properties of the fruits and also indicated the ideal harvesting period for obtaining fruits of optimum quality. [ABSTRACT FROM AUTHOR]

Pigment production and distribution is controlled through multiple genes, resulting in a wide range of coat color phenotypes in dogs. Dogs that produce only the pheomelanin pigment vary in intensity from white to deep red. The Poodle breed has a wide range of officially recognized coat colors, including the pheomelanin-based white, cream, apricot, and red coat colors, which are not fully explained by the previously identified genetic variants involved in pigment intensity. Here, a genome-wide association study for pheomelanin intensity was performed in Poodles which identified an association on canine chromosome 18. Whole-genome sequencing data revealed an SNN retrocopy insertion (SNNL1) in apricot and red Poodles within the associated region on chromosome 18. While equal numbers of melanocytes were observed in all Poodle skin hair bulbs, higher melanin content was observed in the darker Poodles. Several genes involved in melanogenesis were also identified as highly overexpressed in red Poodle skin. The most differentially expressed gene however was GPR22, which was highly expressed in red Poodle skin while unexpressed in white Poodle skin (log2 fold change in expression 6.1, P

Since domestication, horses have been selectively bred for various coat colors and white spotting patterns. To investigate breed distribution, allele frequencies, and potential lethal variants for recommendations on genetic testing, 29 variants within 14 genes were investigated in 11,281 horses from 28 breeds. The recessive chestnut ea allele in melanocortin 1 receptor (MC1R) (p.D84N) was identified in four breeds: Knabstrupper, Paint Horse, Percheron, and Quarter Horse. After filtering for relatedness, ea allele frequency in Knabstruppers was estimated at 0.035, thus illustrating the importance of testing for mate selection for base coat color. The Rocky Mountain Horse breed had the highest allele frequency for two of the dilution variants under investigation (Za.f. = 0.32 and Cha.f. = 0.026); marker-assisted selection in this breed could aid in the production of horses with desirable dilute coats with less severe ocular anomalies caused by the silver (Z) allele. With regard to white patterning, nine horses homozygous for the paired box 3 (PAX3) splashed white 2 (SW2) allele (p.C70Y) and six horses homozygous for the KIT proto-oncogene, receptor tyrosine kinase (KIT) sabino 1 (SB1) allele (ECA3g.79544206A>T) were identified, thus determining they are rare and confirming that homozygosity for SW2 is not embryonic lethal. The KIT dominant white 20 (W20) allele (p.R682H) was identified in all but three breeds: Arabian (n = 151), Icelandic Horse (n = 66), and Norwegian Fjord Horse (n = 90). The role of W20 in pigmentation across breeds is not well understood; given the different selection regimes of the breeds investigated, these data provide justification for further evaluating the functional role of this allele in pigmentation. Here, we present the largest dataset reported for coat color variants in horses to date, and these data highlight the importance of breed-specific studies to inform on the proper use of marker-assisted selection and to develop hypotheses related to pigmentation for further testing in horses.

Introduction: Gingival hyperpigmentation is a common aesthetic concern that often requires treatment to achieve a pleasing smile. While various methods for depigmentation have been described in the literature, the scalpel method is widely advocated. Laser technology, particularly diode lasers, has emerged as a preferred treatment option due to their unique properties. Aim: To compare the efficacy of two different diode wavelengths, namely Denlase and Bluelase lasers, in terms of pain intensity, aesthetic appraisal, and the rate of repigmentation. Materials and Methods: This split-mouth randomised clinical trial was conducted in the Department of Periodontics at Vishnu Dental College, Bhimavarm, Andhra Pradesh, India. over a period of one year with follow-up. A total of 16 patients were included, and the right and left quadrants (both maxilla and mandible) were randomly assigned to either the Denlase or Bluelase group using the coin toss method. Depigmentation using diode lasers at 810 nm and 470 nm wavelengths was carried out in the respective groups. Pain perception, aesthetic appraisal, and recurrence of pigmentation were evaluated at 1, 3, 6, 9 months, and one year. The data were analysed using Friedman’s analysis and the Mann-Whitney U-test. Results: A total of 16 subjects, with a mean age of 27.64±7.64 years and of both genders, were included in the study. Statistically significant differences (p=0.001) were reported in pain perception, aesthetic appraisal, and the rate of repigmentation at 1, 3, 6, 9 months, and one year, respectively. Intergroup comparison revealed an increase in the mean amount of repigmentation at three months in the Denlase group, indicating a recurrence of pigmentation after three months. Conclusion: The Bluelase diode laser (470 nm) demonstrated superior results compared to the Denlase diode laser (810 nm) in terms of pain intensity, aesthetic appraisal, and repigmentation.

Abstract Background The characteristic pink-reddish color in the salmonids fillet is an important, appealing quality trait for consumers and producers. The color results from diet supplementation with carotenoids, which accounts for up to 20–30% of the feed cost. Pigment retention in the muscle is a highly variable phenotype. In this study, we aimed to understand the molecular basis for the variation in fillet color when rainbow trout (Oncorhynchus mykiss) fish families were fed an Astaxanthin-supplemented diet. We used RNA-Seq to study the transcriptome profile in the pyloric caecum, liver, and muscle from fish families with pink-reddish fillet coloration (red) versus those with lighter pale coloration (white). Results More DEGs were identified in the muscle (5,148) and liver (3,180) than in the pyloric caecum (272). Genes involved in lipid/carotenoid metabolism and transport, ribosomal activities, mitochondrial functions, and stress homeostasis were uniquely enriched in the muscle and liver. For instance, the two beta carotene genes (BCO1 and BCO2) were significantly under-represented in the muscle of the red fillet group favoring more carotenoid retention. Enriched genes in the pyloric caecum were involved in intestinal absorption and transport of carotenoids and lipids. In addition, the analysis revealed the modulation of several genes with immune functions in the pyloric caecum, liver, and muscle. Conclusion The results from this study deepen our understanding of carotenoid dynamics in rainbow trout and can guide us on strategies to improve Astaxanthin retention in the rainbow trout fillet.