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Dermatology Practical & Conceptual Apr 2024Studies focused on dermoscopic aspects of pigmented Bowen disease (pBD) in Latin American population are scarce and limited to only case reports or small series.
INTRODUCTION
Studies focused on dermoscopic aspects of pigmented Bowen disease (pBD) in Latin American population are scarce and limited to only case reports or small series.
OBJECTIVES
To report dermoscopic findings in a large series of 147 pBD diagnosed in Ibero-Latin American population.
METHODS
We conducted a multicentric, retrospective study on 147 histologically proven pBD under the auspices of the Dermoscopy Chapter of the Ibero-Latin American College of Dermatology.
RESULTS
The study population consisted of 77 females (52%) and 70 males (48%) with a mean age of 68.6 years. 70.1% of patients had skin phototype 3, 15.6% to skin phototype 2, and 14.3% to skin phototype 4. On clinical examination, near 60% of pBD were flat, 70% presented with scales, and 90% were asymmetric. Under dermoscopy, structureless hypopigmented areas, dots brown and pink color were the most frequently observed. Regarding specific dermoscopic clues to pBD, the most prevalent were structureless hypopigmented areas, vessels arranged in linear fashion at the periphery, and pigmented lines or pigmented dots distributed in a linear fashion. Clustered, coiled, and dotted vessels were observed in 55.8%, 45.6%, and 45.6% of the cases, respectively.
CONCLUSIONS
We report a large series of cases of pBD in Latin American patients, with most patients being skin phototype 3 and 4. Distinctively in our study, the pigmented structures and the clues derived from the presence of melanin were much more frequent than in previous reports in fair skin.
PubMed: 38810038
DOI: 10.5826/dpc.1402a86 -
Microbiology Spectrum May 2024The complex (Bcc) is a group of Gram-negative opportunistic bacteria often associated with fatal pulmonary infections in patients with impaired immunity, particularly...
Mutation of , encoding homogentisate 1,2-dioxygenase, is responsible for pyomelanin production but does not impact the virulence of in a chronic granulomatous disease mouse lung infection.
The complex (Bcc) is a group of Gram-negative opportunistic bacteria often associated with fatal pulmonary infections in patients with impaired immunity, particularly those with cystic fibrosis (CF) and chronic granulomatous disease (CGD). Some Bcc strains are known to naturally produce pyomelanin, a brown melanin-like pigment known for scavenging free radicals; pigment production has been reported to enable Bcc strains to overcome the host cell oxidative burst. In this work, we investigated the role of pyomelanin in resistance to oxidative stress and virulence in strains J2315 and K56-2, two epidemic CF isolates belonging to the ET-12 lineage. We previously reported that a single amino acid change from glycine to arginine at residue 378 in homogentisate 1,2-dioxygenase (HmgA) affects the pigment production phenotype: pigmented J2315 has an arginine at position 378, while non-pigmented K56-2 has a glycine at this position. Herein, we performed allelic exchange to generate isogenic non-pigmented and pigmented strains of J2315 and K56-2, respectively, and tested these to determine whether pyomelanin contributes to the protection against oxidative stress as well as in a respiratory infection in CGD mice . Our results indicate that the altered pigment phenotype does not significantly impact these strains' ability to resist oxidative stress with HO and NO and did not change the virulence and infection outcome in CGD mice suggesting that other factors besides pyomelanin are contributing to the pathophysiology of these strains.IMPORTANCEThe complex (Bcc) is a group of Gram-negative opportunistic bacteria that are often associated with fatal pulmonary infections in patients with impaired immunity, particularly those with cystic fibrosis and chronic granulomatous disease (CGD). Some Bcc strains are known to naturally produce pyomelanin, a brown melanin-like pigment known for scavenging free radicals and overcoming the host cell oxidative burst. We investigated the role of pyomelanin in strains J2315 (pigmented) and K56-2 (non-pigmented) and performed allelic exchange to generate isogenic non-pigmented and pigmented strains, respectively. Our results indicate that the altered pigment phenotype does not significantly impact these strains' ability to resist HO or NO and did not alter the outcome of a respiratory infection in CGD mice . These results suggest that pyomelanin may not always constitute a virulence factor and suggest that other features are contributing to the pathophysiology of these strains.
PubMed: 38809005
DOI: 10.1128/spectrum.00410-24 -
Autopsy & Case Reports 2024Esophageal melanocytosis is a rare entity defined by the proliferation of a melanocytic basal layer of the esophageal squamous lining and deposition of melanin in the...
Esophageal melanocytosis is a rare entity defined by the proliferation of a melanocytic basal layer of the esophageal squamous lining and deposition of melanin in the esophageal mucosa. Esophageal melanocytosis is considered a benign entity of unknown etiology; however, it has been reported as a melanoma precursor. We report a case of esophageal melanocytosis in a diabetic and hypertensive 67-year-old male with recurrent dizziness and syncope for the past 6 months. Given his complaint of dyspepsia, he underwent an upper gastrointestinal endoscopy, in which an esophageal biopsy revealed the diagnosis of esophageal melanocytosis. The definitive diagnosis of esophageal melanocytosis can only be made by histological analysis. The histologic differential diagnoses include melanocytic nevi and malignant melanoma. Therefore, they need to be ruled out.
PubMed: 38803486
DOI: 10.4322/acr.2024.487 -
Clinical, Cosmetic and Investigational... 2024Melasma is a common challenge in the field of pigmentary skin disorders, exerting a significant emotional and psychosocial burden on patients. The persistent and... (Review)
Review
Melasma is a common challenge in the field of pigmentary skin disorders, exerting a significant emotional and psychosocial burden on patients. The persistent and recurring nature of melasma complicates its management in routine clinical practice. This comprehensive review outlines a stepwise, practical approach encompassing diagnostic, preventive and therapeutic strategies for the management of melasma. A thorough exploration of aggravating and exacerbating factors, including sun exposure, hormonal imbalances, photosensitizing medication and cosmetics, is essential for a holistic assessment of the disease. With an emphasis on consistent and effective photoprotection, initial topical treatment modalities target the melanin production and/or the transfer of melanosomes to keratinocytes. Topical tyrosine inhibitors emerge as the first choice for reducing and preventing hyperpigmentation, with compounds such as thiamidol or tranexamic acid (TXA) being preferred for their safety profile over hydroquinone (HQ), kojic acid and arbutin. Combination with chemical peels can further enhance the therapeutic efficacy, even in cases with resistant melasma. In more severe cases, laser- and light-based interventions may be considered, but with the caveat of the likelihood of recurrence within 3-6 months. Assisted TXA delivery, via either fractional non-ablative laser or microneedling techniques, can further improve clinical outcomes. In conclusion, an optimal melasma management strategy is a multimodal approach, which includes effective photoprotection and a mix of different topical treatments targeting melanin synthesis, the anti-inflammatory environment, senescence and vascularity. Complementary procedures, such as chemical peels, and laser, light-based or microneedling procedures, with or without TXA, can further expedite melanin clearance in more severely affected instances. Individual discussions with patients regarding treatment expectations, recurrence likelihood and potential side effects are paramount to a comprehensive and successful therapeutic journey.
PubMed: 38800358
DOI: 10.2147/CCID.S372456 -
Cureus Apr 2024A new injectable solution containing low-molecular-weight hyaluronic acid (HA) and a specific amino acid mixture was formulated with proper aesthetic performance for the...
A new injectable solution containing low-molecular-weight hyaluronic acid (HA) and a specific amino acid mixture was formulated with proper aesthetic performance for the main signs of facial skin photoaging. The present study aimed to investigate its new application for rejuvenating and augmenting labia majora using clinical and biometric assessments. Three sessions of intradermal injections were performed using 3 ml of test extracellular matrix (ECM) for 10 eligible post-menopause female subjects (age 53.6 ± 7.93 years). The effectiveness of the intervention was assessed by an independent physician using before-and-after pictures based on the physician's global assessment score. Objective biophysical skin assessments, including skin hydration, skin erythema, and melanin index, as well as elasticity parameters including firmness (R0), gross elasticity (R2), and net elasticity (R5), were also performed before the first injection and then on the 2nd and 12th weeks after the last session. Patients' satisfaction and all reported or observed adverse events were documented. At week 12, all the subjects reported an aesthetic improvement of 25% or more in rejuvenation and sagging of the labia major area. A statistically significant improvement was also detected in R0 and R5 at week 12 (p-values 0.005 and 0.022, respectively). Patient satisfaction surveys revealed a median score of 8 at both follow-up visits. The results showed a new indication of the tested HA ECM for providing a beneficial, durable, rejuvenating effect on the labia majora with a good safety profile.
PubMed: 38800301
DOI: 10.7759/cureus.58970 -
Plants (Basel, Switzerland) May 2024fructus is widely used in traditional Oriental medicine for treating female genital disorders, male impotence, frigidity, and skin-related conditions in East Asia....
fructus is widely used in traditional Oriental medicine for treating female genital disorders, male impotence, frigidity, and skin-related conditions in East Asia. However, the role of fructus extract (CMFE) in melanin synthesis is not well elucidated. This study aimed to investigate the anti-melanogenesis effect and mechanism of action of CMFE in α-MSH-stimulated B16F10 cells. Intracellular melanin content and tyrosinase activity were measured in α-MSH-stimulated B16F10 cells treated with various concentrations of CMFE (0.5-5 μg/mL). mRNA and protein levels of tyrosinase and MITF were evaluated using qRT-PCR and ting. CMFE's effect on the proteasomal degradation of tyrosinase was confirmed using a proteasomal degradation inhibitor, MG132. CMFE treatment activated p38, a protein associated with proteasomal degradation. Treatment with CMFE at up to 5 μg/mL showed no significant cytotoxicity. CMFE significantly reduced α-MSH-stimulated melanin production (43.29 ± 3.55% decrease, < 0.05) and cellular tyrosinase activity (31.14 ± 3.15% decrease, < 0.05). Although mRNA levels of MITF and tyrosinase increased, CMFE suppressed tyrosinase protein levels. The suppressive effect of CMFE on tyrosinase protein was blocked by MG132. CMFE inhibited melanogenesis by promoting the proteasome degradation of tyrosinase through p38 activation. These findings suggest that CMFE has the potential to be a natural whitening agent for inhibiting melanogenesis.
PubMed: 38794376
DOI: 10.3390/plants13101305 -
International Journal of Molecular... May 2024Epidermal melanin synthesis determines an individual's skin color. In humans, melanin is formed by melanocytes within the epidermis. The process of melanin synthesis...
Epidermal melanin synthesis determines an individual's skin color. In humans, melanin is formed by melanocytes within the epidermis. The process of melanin synthesis strongly depends on a range of cellular factors, including the fine-tuned interplay with reactive oxygen species (ROS). In this context, a role of cold atmospheric plasma (CAP) on melanin synthesis was proposed due to its tunable ROS generation. Herein, the argon-driven plasma jet kINPen MED was employed, and its impact on melanin synthesis was evaluated by comparison with known stimulants such as the phosphodiesterase inhibitor IBMX and UV radiation. Different available model systems were employed, and the melanin content of both cultured human melanocytes (in vitro) and full-thickness human skin biopsies (in situ) were analyzed. A histochemical method detected melanin in skin tissue. Cellular melanin was measured by NIR autofluorescence using flow cytometry, and a highly sensitive HPLC-MS method was applied, which enabled the differentiation of eu- and pheomelanin by their degradation products. The melanin content in full-thickness human skin biopsies increased after repeated CAP exposure, while there were only minor effects in cultured melanocytes compared to UV radiation and IBMX treatment. Based on these findings, CAP does not appear to be a useful option for treating skin pigmentation disorders. On the other hand, the risk of hyperpigmentation as an adverse effect of CAP application for wound healing or other dermatological diseases seems to be neglectable.
Topics: Humans; Melanins; Melanocytes; Plasma Gases; Epidermis; Ultraviolet Rays; Skin Pigmentation; Cells, Cultured; Reactive Oxygen Species; Biopsy; Melanogenesis
PubMed: 38791225
DOI: 10.3390/ijms25105186 -
Antioxidants (Basel, Switzerland) Apr 2024Hyperpigmentation occurs due to irregular secretion of melanin pigment in the skin. This can affect quality of life depending on its severity, so prevention and...
Hyperpigmentation occurs due to irregular secretion of melanin pigment in the skin. This can affect quality of life depending on its severity, so prevention and management are essential. Oats ( L.), a grain consumed worldwide, are known to offer improved health benefits upon germination and fermentation. This study is aimed to investigate the protective effects of lactobacilli-fermented sprouted oat extracts on oxidative stress and melanin overproduction in vitro. The anti-melanogenic effect was investigated using melanin content and tyrosinase activity assays in B16F10 cells, as well as a mushroom tyrosinase-based enzyme inhibition assay. The results showed that -fermented oat extracts were the most effective for reducing melanin formation by reducing the mRNA expression of microphthalmia-associated transcription factor, tyrosinase, and tyrosinase-related protein 2. Furthermore, fermentation was effective in improving the total phenolic, flavonoid, and avenanthramide A contents of sprouted oat extracts. The results also demonstrated the antioxidant effects of -fermented sprouted oat extracts in promoting DPPH radical-scavenging activity, superoxide dismutase-like activity, and reduction in reactive oxygen species levels. Overall, the findings indicate that fermented sprouted oat extracts are promising candidates for antioxidant and anti-hyperpigmentation treatments.
PubMed: 38790649
DOI: 10.3390/antiox13050544 -
Toxics May 2024In this study, a semi-static water exposure method was employed to investigate the early developmental and neurotoxic effects of four benzothiazole substances (BTHs),...
In this study, a semi-static water exposure method was employed to investigate the early developmental and neurotoxic effects of four benzothiazole substances (BTHs), namely benzothiazole (BTH), 2-mercaptobenzothiazole (MBT), 2-hydroxybenzothiazole (BTON), and 2-aminobenzothiazole (2-ABTH), on zebrafish at an equimolar concentration of 10 μM. The findings revealed that all four BTHs exerted certain impacts on early development in zebrafish. MBT stimulated spontaneous movement in juvenile zebrafish, whereas BTON inhibited such movements. Moreover, all four BTHs hindered the hatching process of zebrafish larvae, with MBT exhibiting the strongest inhibition at 24 h post-fertilization (hpf). Notably, MBT acted as a melanin inhibitor by suppressing melanin production in juvenile zebrafish eyes and weakening phototaxis. Additionally, both BTH and BTON exhibited significantly lower speeds than the control group and other test groups under conditions without bright field stimulation; however, their speeds increased to average levels after percussion stimulation, indicating no significant alteration in motor ability among experimental zebrafish groups. Short-term exposure to these four types of BTHs induced oxidative damage in zebrafish larvae; specifically, BTH-, MBT-, and BTON-exposed groups displayed abnormal expression patterns of genes related to oxidative damage. Exposure to both BTH and MBT led to reduced fluorescence intensity in transgenic zebrafish labeled with central nervous system markers, suggesting inhibition of central nervous system development. Furthermore, real-time quantitative PCR results demonstrated abnormal gene expression associated with neural development. However, no significant changes were observed in 2-ABTH gene expression at this concentration. Overall findings indicate that short-term exposure to BTHs stimulates neurodevelopmental gene expression accompanied by oxidative damage.
PubMed: 38787120
DOI: 10.3390/toxics12050341 -
Marine Drugs May 2024In regions reliant on fisheries for livelihoods, a significant number of fish by-products are generated annually due to processing. These discarded parts contain... (Review)
Review
In regions reliant on fisheries for livelihoods, a significant number of fish by-products are generated annually due to processing. These discarded parts contain valuable biological resources, such as proteins, fish oils, and trace elements, thus holding enormous potential for reutilization. In recent years, fish by-product proteins have been widely utilized in skincare products due to their rich collagen content, biosafety, and biocompatibility. This review summarizes the research into and applications of fish by-product proteins in skin health, including alleviating oxidative stress and skin inflammation, reducing DNA damage, mitigating melanin production, improving skin hydration, slowing skin matrix degradation, and promoting synthesis. Additionally, the possibility of improving skin health by improving the abundance of gut microbiota is also discussed. This review underscores the importance of fish by-product proteins in the fisheries, food processing, cosmetics, and biomedical industries.
Topics: Animals; Humans; Skin; Fish Proteins; Fishes; Cosmetics; Oxidative Stress
PubMed: 38786606
DOI: 10.3390/md22050215