Primary cutaneous apocrine carcinoma: A challenging case report.

INTRODUCTION: Primary cutaneous apocrine carcinomas of the axilla represents an extremely rare entity, with <200 cases reported in the literature. It can be challenging, even almost impossible, to distinguish histologically from metastases of breast origin. We herein present the first case of an axillary cutaneous apocrine adenocarcinoma followed and treated in our institute. CASE PRESENTATION: A 58-year-old man with a history of myopathy, presented for a right axillary swelling. Physical examination revealed the presence of a 10 cm right axillary mass, no palpable adenopathy, and bilateral gynecomastia. A biopsy of the mass was performed, showing a pattern consistent with a secondary localization of mammary neoplasia. Breast and distant radiological examinations were negative. The tumor markers' levels were not raised. Therefore, the patient underwent surgery with a large excision, a right axillary lymph node dissection, covered with a pedicled pectoralis major flap. Histological and immunohistochemical examinations showed a high expression of CK7 with a negative expression of TTF1, RH, PSA, and CK20. The diagnosis of an apocrine adenocarcinoma from cutaneous origin was confirmed. CLINICAL DISCUSSION: Primary cutaneous apocrine carcinomas are a group of uncommon malignant adnexal tumors, whose diagnosis is almost impossible to confirm preoperatively. Wide, local excision with clear margins, with or without lymph node dissection is the standard treatment. CONCLUSION: This case illustrates the importance of clinico-pathological correlation of skin cancers, especially apocrine ones. Clinical particularity and careful histological analysis are used to guide the diagnostic approach.

Pregnancy-Related Eccrine Angiomatous Hamartoma: Case Report.

Eccrine angiomatous hamartoma is rare, slow-growing, and benign neoplasm that is diagnosed based on clinical characteristics and histological findings. It usually presents as a solitary nodule on the extremities and may arise at birth or in childhood. Although it is usually asymptomatic, in some cases it can cause pain and hyperhidrosis. From a histological perspective, it is characterized by an increase in the number of eccrine glands and a proliferation of vascular channels. We present the case of a 26-year-old woman who developed an eccrine angiomatous hamartoma in her right leg. The rapid growth of the lesion during pregnancy coupled with the challenges posed by a superficial biopsy, complicated the differential diagnosis.

Primary cutaneous mucinous carcinoma of the scalp masquerading as a benign dermatological mass - A case report.

INTRODUCTION AND IMPORTANCE: Primary cutaneous mucinous carcinoma (PCMC) is a rare low-grade malignant neoplasm derived from the sweat glands. Local recurrence of PCMC occurs frequently, but these lesions rarely metastasize. Due to the absence of classical demographic and clinical characteristics, PCMCs masquerade as sebaceous cyst, lipoma, pilomatrixoma, chalazion, or squamous cell carcinoma. This misdiagnosis frequently leads to incomplete surgical excision which necessitates further surgical therapy for a curative intent. CASE PRESENTATION: We present a case of PCMC in a 45-year-old woman which presented as a slow- growing and symptomless nodule in the scalp. After clinical evaluation, the patient had a typical surgical excision for a benign-looking lesion. Histological evaluation of the specimen confirmed a localized PCMC in the scalp with involved surgical margins. CLINICAL DISCUSSION: A thorough oncological assessment by PET-CT scan and radionuclide scintigraphy was performed. Later, a wide local excision using a gamma probe for intra-operative radionuclide localization of the tumor area and sentinel lymph nodes was done. CONCLUSION: The patient did not have any regional or distant metastases and remained stable at the time of reporting this case.

Epidermal and dermal cells from adult rat eccrine sweat gland-containing skin can reconstruct the three-dimensional structure of eccrine sweat glands.

BACKGROUND: Previously, we have demonstrated that eccrine sweat gland cells (ESGCs) can reconstruct the three-dimensional (3D) structure of eccrine sweat glands (ESGs). However, there is still a need to explore source cells capable of regenerating ESG to address the issue of ESG regeneration in ESGC-deficient conditions, such as severe burns. METHODS: The epidermal cells and dermal cells in adult rat ventral foot skin (ESG-bearing) were isolated. The isolated single epidermal cells and dermal cells were mixed with Matrigel, and then the mixture was implanted into the axillary/inguinal fat pads of nude mice. Five weeks after implantation, the Matrigel plugs were harvested and the morphology and differentiation of the cells were examined by H&E staining and fluorescent immunohistochemical staining for ESG markers, such as Na+ -K+ -2Cl- cotransporter 1 (NKCC1), Na+ -K+ -ATPase (NKA), Foxa1 and K14. RESULTS: The epidermal cells and dermal cells of adult rat ventral foot skin can reconstruct 3D structure and express specific markers of ESGs in skin, such as NKCC1, NKA and Foxa1, indicating the ESG-phenotypic differentiation of the 3D structures. Double immunofluorescence staining showed that some 3D structures expressed both the myoepithelial cell marker alpha-SMA and the common marker K14 of duct cells and myoepithelial cells, while some 3D structures expressed only K14, indicating that ESG-like 3D structures differentiated into duct-like and secretory coiled cells. CONCLUSION: Epidermal and dermal cells from adult ESG-bearing skin can be used as a cell source for ESG regeneration.

Development of Physiologically Relevant Skin Organoids from Human Induced Pluripotent Stem Cells.

The development of skin organs for studying developmental pathways, modeling diseases, or regenerative medicine purposes is a major endeavor in the field. Human induced pluripotent stem cells (hiPSCs) are successfully used to derive skin cells, but the field is still far from meeting the goal of creating skin containing appendages, such as hair follicles and sweat glands. Here, the goal is to generate skin organoids (SKOs) from human skin fibroblast or placental CD34+ cell-derived hiPSCs. With all three hiPSC lines, complex SKOs with stratified skin layers and pigmented hair follicles are generated with different efficacies. In addition, the hiPSC-derived SKOs develop sebaceous glands, touch-receptive Merkel cells, and more importantly eccrine sweat glands. Together, physiologically relevant skin organoids are developed by direct induction of embryoid body formation, along with simultaneous inactivation of transforming growth factor beta signaling, activation of fibroblast growth factor signaling, and inhibition of bone morphogenetic protein signaling pathways. The skin organoids created in this study can be used as valuable platforms for further research into human skin development, disease modeling, or reconstructive surgeries.

Primary Cutaneous Apocrine Carcinoma and Syringocystadenoma Papilliferum Arising in Nevus Sebaceus: A Case Report and Review of the Literature.

Nevus sebaceus is a hamartomatous lesion characterized by epidermal, follicular, sebaceus, and apocrine gland abnormalities. Approximately 25% of affected individuals may develop benign or malignant secondary neoplasms within the preceding nevus sebaceus. Primary cutaneous apocrine carcinoma (PCAC) is a rare malignant skin tumor affecting elderly adults in their sixth decade of life. Histologically, PCAC appears as a dermal tumor displaying apocrine differentiation with decapitation secretion and malignant features. Secondary malignancy arising from nevus sebaceus is a rare complication, especially for apocrine carcinoma. To date, approximately 200 cases of PCAC have been reported in the literature, and only a few cases have developed PCAC on the scalp. Very few cases (approximately only 12) of PCACs developing in nevus sebaceus have been reported. Here, we report an extremely rare case of the coexistence of PCAC and syringocystadenoma papilliferum arising within nevus sebaceus of the scalp.

Epithelial polarity-driven membrane separation but not cavitation regulates lumen formation of rat eccrine sweat glands.

BACKGROUND: Each eccrine sweat gland (ESG) is a single-tubular structure with a central lumen, and the formation of hollow lumen in the initial solid cell mass is a key developmental process. To date, there are no reports on the mechanism of native ESG lumen formation. METHODS: To investigate the lumen morphogenesis and the lumen formation mechanisms of Sprague-Dawley (SD) rat ESGs, SD rat hind-footpads at E20.5, P1-P5, P7, P9, P12, P21, P28 and P56 were obtained. The lumen morphogenesis of ESGs was examined by HE staining and immunofluorescence staining for polarity markers. The possible mechanisms of lumen formation were detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) apoptosis assay and autophagy marker LC3B immunofluorescence staining, and further explored by ouabain intervention experiment. RESULTS: In SD rat ESGs, the microlumen was formed at P1, and the small intact lumen with apical-basal polarity appeared at P3. The expression of apical marker F-actin, basal marker Laminin, basolateral marker E-cadherin was consistent with the timing of lumen formation of SD rat ESGs. During rat ESG development, apoptosis and autophagy were not detected. However, inhibition of Na+-K+-ATPase (NKA) with ouabain resulted in decreased lumen size, although neither the timing of lumen formation nor the expression of polarity proteins was altered. CONCLUSIONS: Epithelial polarity-driven membrane separation but not cavitation regulates lumen formation of SD rat ESGs. NKA-regulated fluid accumulation drives lumen expansion.

Genetics of adnexal tumors: An update.

Cutaneous adnexal tumors form a vast heterogeneous group that include frequent entities that are mostly benign, as well as rare tumors that are occasionally malignant. In contrast to cutaneous tumors arising from the interfollicular epidermis that develop as a result of accumulation of UV-induced DNA damage (basal cell carcinoma, squamous cell carcinoma), the oncogenesis of adnexal tumors is related to a broad spectrum of genetic mechanisms (e.g., point mutation, fusion genes, viral integration, etc.). In this setting, specific and recurrent genetic alterations have been progressively reported, and these allow better classification of these entities. For certain of them, immunohistochemical tools are now available, enabling precise integrated histological and molecular diagnosis since certain entities are linked to well-defined alterations. In this context, we aim in this review to summarize the main molecular tools currently available for the classification of adnexal tumors.

Decay of Skin-Specific Gene Modules in Pangolins.

The mammalian skin exhibits a rich spectrum of evolutionary adaptations. The pilosebaceous unit, composed of the hair shaft, follicle, and the sebaceous gland, is the most striking synapomorphy. The evolutionary diversification of mammals across different ecological niches was paralleled by the appearance of an ample variety of skin modifications. Pangolins, order Pholidota, exhibit keratin-derived scales, one of the most iconic skin appendages. This formidable armor is intended to serve as a deterrent against predators. Surprisingly, while pangolins have hair on their abdomens, the occurrence of sebaceous and sweat glands is contentious. Here, we explore various molecular modules of skin physiology in four pangolin genomes, including that of sebum production. We show that genes driving wax monoester formation, Awat1/2, show patterns of inactivation in the stem pangolin branch, while the triacylglycerol synthesis gene Dgat2l6 seems independently eroded in the African and Asian clades. In contrast, Elovl3 implicated in the formation of specific neutral lipids required for skin barrier function is intact and expressed in the pangolin skin. An extended comparative analysis shows that genes involved in skin pathogen defense and structural integrity of keratinocyte layers also show inactivating mutations: associated with both ancestral and independent pseudogenization events. Finally, we deduce that the suggested absence of sweat glands is not paralleled by the inactivation of the ATP-binding cassette transporter Abcc11, as previously described in Cetacea. Our findings reveal the sophisticated and complex history of gene retention and loss as key mechanisms in the evolution of the highly modified mammalian skin phenotypes.

Impact of Brahman genetics on skin histology characteristics with implications for heat tolerance in cattle.

Cattle lose heat predominantly through cutaneous evaporation at the skin-hair coat interface when experiencing heat stress. Sweating ability, sweat gland properties, and hair coat properties are a few of the many variables determining the efficacy of evaporative cooling. Sweating is a significant heat dissipation mechanism responsible for 85% of body heat loss when temperatures rise above 86°F. The purpose of this study was to characterize skin morphological parameters in Angus, Brahman, and their crossbred cattle. Skin samples were taken during the summer of 2017 and 2018 from a total of 319 heifers from six breed groups ranging from 100% Angus to 100% Brahman. Epidermis thickness decreased as the percentage of Brahman genetics increased where the 100% Angus group had a significantly thicker epidermis compared to the 100% Brahman animals. A more extended epidermis layer was identified in Brahman animals due to more pronounced undulations in this skin layer. Breed groups with 75% and 100% Brahman genes were similar and had the largest sweat gland area, indicative of superior resilience to heat stress, compared to breed groups with 50% or lower Brahman genetics. There was a significant linear breed group effect on sweat gland area indicating an increase of 862.0 µm2 for every 25% increase in Brahman genetics. Sweat gland length increased as the Brahman percentage increased, while the sweat gland depth showed an opposite trend, decreasing from 100% Angus to 100% Brahman. The number of sebaceous glands was highest in 100% Brahman animals which had about 1.77 more sebaceous glands (p < 0.05) per 4.6 mm2area. Conversely, the sebaceous gland area was greatest in the 100% Angus group. This study identified significant differences in skin properties related to heat exchange ability between Brahman and Angus cattle. Equally important, these differences are also accompanied by significant levels of variation within each breed, which is indicative that selection for these skin traits would improve the heat exchange ability in beef cattle. Further, selecting beef cattle for these skin traits would lead to increased resilience to heat stress without disrupting production traits.

In vivo assessments of microneedle arrays and iontophoresis of pilocarpine in human palmar sweating.

Emotional stress-induced sweating in glabrous skin of the palm and sole, which can be excessive in some individuals (hyperhidrosis), can negatively impact quality of life. Understanding the mechanisms underlying this response can lead to potential treatments. Transdermal iontophoresis is a method to administer ionized sudorific agents to sweat glands within the dermis. However, due to the reduced permeability of pharmacological agents in thicker skin such as the palms, this technique has been shown to be less effective when applied in thicker skin. Thus, we assessed the effectiveness of pre-treating palmar skin with microneedles to create micropores on the stratum corneum of the palm to enhance the iontophoretic delivery of pilocarpine to modulate sweat production. On three separate sessions, we applied microneedles (0.78 cm2, 190 needles with a length of 875 µm) to palm and forearm skin sites. Upon removal of the microneedles, we assessed the number of perforations colored by gentian violet in the forearm only (Protocol 1, n = 20), skin barrier function indexed by transepidermal water loss (TEWL) (Protocol 2, n = 21), and sweating induced by the iontophoretic application of 1% pilocarpine (Protocol 3, n = 43). Briefly, we measured 1) ∼172 dyed spots on forearm skin, 2) an increase of ∼300% and âˆ¼ 900% in TEWL on palm and forearm skin, respectively; and 3) a 2-fold increase in sweating on the palm only following the application of the microneedles. Notably, the microneedle array failed to enhance pilocarpine delivery at either the palm or forearm skin sites. We showed the application of a microneedle array enhanced skin permeability and sweat production on the palm without a concomitant increase in pilocarpine delivery. Therefore, this methodology could be employed to advance our understanding of the causes and treatments of medical conditions such as hyperhidrosis.

A Causal Treatment for X-Linked Hypohidrotic Ectodermal Dysplasia: Long-Term Results of Short-Term Perinatal Ectodysplasin A1 Replacement.

X-linked hypohidrotic ectodermal dysplasia (XLHED), caused by a genetic deficiency of ectodysplasin A1 (EDA1), is a rare developmental disorder of ectodermal derivatives such as hair, sweat glands, and teeth. The absence of sweat glands and perspiration can evoke life-threatening hyperthermia. As molecular genetic findings are not always conclusive, the concentrations of circulating EDA1 may help to distinguish between total and partial EDA1 deficiencies. We previously treated nine male patients with obvious signs of XLHED with a recombinant EDA1 replacement protein, Fc-EDA, either shortly after birth (n = 3) or by prenatal administration in gestational week 26 and beyond (n = 6). Here, we present the long-term follow-up for up to six years. In patients who had received Fc-EDA after birth, neither sweat glands nor sweating ability were detected at the age of 12-60 months. In contrast, prenatal EDA1 replacement resulted in ample sweat gland development and pilocarpine-inducible sweating in all treated subjects, who also attained more permanent teeth than their untreated affected relatives. Normal perspiration has persisted for six years in the two oldest boys treated repeatedly with Fc-EDA in utero. When they had a sauna, adequate thermoregulation was evidenced. Lower sweat production after single prenatal dosing may indicate a dose-response relationship. The absence of circulating EDA1 in five prenatally treated subjects proved that these children would have been unable to perspire if they had been left untreated. The sixth infant was shown to produce an EDA1 molecule that, albeit interacting with its cognate receptor, cannot activate EDA1 signaling. In conclusion, a causal treatment of XLHED before birth is feasible.

Case Report and Review of the Pathophysiology and Therapeutics of Adult Hematohidrosis.

Hematohidrosis is an extremely rare condition characterized by the oozing or secretion of blood through intact skin and mucosa, particularly through eccrine glands. Although there is not much literature available on the condition, examples of Hematohidrosis include the crying and sweating of blood. The fluid may have a bloody tinge or may be frank blood. The anomaly has no identifiable etiology, and patients generally present in a good state of health. In this report, we present a 19-year-old female who had weekly occurrences of bloody diaphoresis that had been present consistently for one year. During her presentation at the hematology clinic, she was investigated thoroughly for alternative causes, but none were found. The patient was diagnosed with hematohidrosis and was offered treatment with propranolol, which she declined. She continues to follow up routinely in the hematology clinic with persistent symptoms.

Deodorants and antiperspirants: New trends in their active agents and testing methods.

Sweating is the human body's thermoregulation system but also results in unpleasant body odour which can diminish the self-confidence of people. There has been continued research in finding solutions to reduce both sweating and body odour. Sweating is a result of increased sweat flow and malodour results from certain bacteria and ecological factors such as eating habits. Research on deodorant development focuses on inhibiting the growth of malodour-forming bacteria using antimicrobial agents, whereas research on antiperspirant synthesis focuses on technologies reducing the sweat flow, which not only reduces body odour but also improves people's appearance. Antiperspirant's technology is based on the use of aluminium salts which can form a gel plug at sweat pores, obstructing the sweat fluid from arising onto the skin surface. In this paper, we perform a systematic review on the recent progress in the development of novel antiperspirant and deodorant active ingredients that are alcohol-free, paraben-free, and naturally derived. Several studies have been reported on the alternative class of actives that can potentially be used for antiperspirant and body odour treatment including deodorizing fabric, bacterial, and plant extracts. However, a significant challenge is to understand how the gel-plugs of antiperspirant actives are formed in sweat pores and how to deliver long-lasting antiperspirant and deodorant benefits.

La transpiration est le système de thermorégulation de l'organisme, mais elle entraîne également une odeur corporelle désagréable qui peut diminuer la confiance en soi. Des nombreuses recherches ont été menées afin de trouver des solutions pour réduire à la fois la transpiration et l'odeur corporelle. La transpiration est le résultat de l'augmentation du flux de sueur, et les mauvaises odeurs sont dues à certaines bactéries et à certains facteurs écologiques tels que les habitudes alimentaires. Les recherches sur le développement des déodorants se concentrent sur l'inhibition de la croissance des bactéries responsables des mauvaises odeurs à l'aide d'agents antimicrobiens, tandis que les recherches sur la synthèse des anti-transpirants se concentrent sur les technologies diminuant le flux de sueur, ce qui réduire non seulement les odeurs corporelles, mais améliore également l'apparence des personnes. La technologie des anti-transpirants repose sur l'utilisation de sels d'aluminium qui peuvent former un bouchon de gel au niveau des pores sudoripares, empêchant le liquide sudoral d'apparaître à la surface de la peau. Dans cet article, nous effectuons une revue systématique des progrès récents réalisés dans le développement de nouveaux principes actifs anti-transpirants et déodorants qui sont sans alcool, sans parabène et d'origine naturelle. Plusieurs études ont été rapportées sur la classe alternative de principes actifs qui peuvent potentiellement être utilisés pour le traitement anti-transpirant et des odeurs corporelles, y compris les tissus désodorisants, les bactéries et les extraits végétaux. Cependant, un défi important consiste à comprendre comment les bouchons de gel des actifs anti-transpirants se forment au niveau des pores sudoripares, et comment offrir des effets anti-transpirants et déodorants durables.

Protocol for the Phase 2 EDELIFE Trial Investigating the Efficacy and Safety of Intra-Amniotic ER004 Administration to Male Subjects with X-Linked Hypohidrotic Ectodermal Dysplasia.

X-linked hypohidrotic ectodermal dysplasia (XLHED) is a rare genetic disorder characte-rised by abnormal development of the skin and its appendages, such as hair and sweat glands, the teeth, and mucous glands of the airways, resulting in serious, sometimes life-threatening complications like hyperthermia or recurrent respiratory infections. It is caused by pathogenic variants of the ectodysplasin A gene (EDA). Most affected males are hemizygous for EDA null mutations that lead to the absence or inactivity of the signalling protein ectodysplasin A1 (EDA1) and, thus, to the full-blown phenotype with inability to perspire and few if any teeth. There are currently no long-term treatment options for XLHED. ER004 represents a first-in-class protein replacement molecule designed for specific, high-affinity binding to the endogenous EDA1 receptor (EDAR). Its proposed mechanism of action is the replacement of missing EDA1 in yet unborn patients with XLHED. Once bound to EDAR, ER004 activates the EDA/NFκB signalling pathway, which triggers the transcription of genes involved in the normal development of multiple tissues. Following preclinical studies, named-patient use cases demonstrated significant potential of ER004 in affected males treated in utero during the late second and third trimesters of pregnancy. In order to confirm these results, we started the EDELIFE trial, a prospective, open-label, genotype-match controlled, multicentre clinical study to investigate the efficacy and safety of intra-amniotic ER004 administration as a prenatal treatment for male subjects with XLHED. This article summarises the rationale, the study protocol, ethical issues of the trial, and potential pitfalls.

Effect of reflex and mechanical decreases in skin perfusion on thermal- and agonist-induced eccrine sweating in humans.

In humans, skin blood flux (SkBF) and eccrine sweating are tightly coupled, suggesting common neural control and regulation. This study was designed to separate these two sympathetic nervous system end-organ responses via nonadrenergic SkBF-decreasing mechanical perturbations during heightened sudomotor drive. We induced sweating physiologically via whole body heat stress using a high-density tube-lined suit (protocol 1; 2 women, 4 men), and pharmacologically via forearm intradermal microdialysis of two steady-state doses of a cholinergic agonist, pilocarpine (protocol 2; 4 women, 3 men). During sweating induction, we decreased SkBF via three mechanical perturbations: arm and leg dependency to engage the cutaneous venoarteriolar response (CVAR), limb venous occlusion to engage the CVAR and decrease perfusion pressure, and limb arterial occlusion to cause ischemia. In protocol 1, heat stress increased arm cutaneous vascular conductance and forearm sweat rate (capacitance hygrometry). During heat stress, despite decreases in SkBF during each of the acute (3 min) mechanical perturbations, eccrine sweat rate was unaffected. During heat stress with extended (10 min) ischemia, sweat rate decreased. In protocol 2, both pilocarpine doses (ED50 and EMAX) increased SkBF and sweat rate. Each mechanical perturbation resulted in decreased SkBF but minimal changes in eccrine sweat rate. Taken together, these data indicate that a wide range of acute decreases in SkBF do not appear to proportionally decrease either physiologically- or pharmacologically induced eccrine sweating in peripheral skin. This preservation of evaporative cooling despite acutely decreased SkBF could have consequential impacts for heat storage and balance during changes in body posture, limb position, or blood flow restrictive conditions.

Effect of Boron on Sympathetic Skin Response in Rats.

Background: Boron effects on reproduction and growth have been extensively studied in animals. Electrodermal activity (EDA) reflects the activity of eccrine sweat glands stimulated by the release of acetylcholine from sympathetic nerves. Aim: In the presen study, it was aimed to examine the effect of boron, which was turned into cream, on sweat glands. Methods: A cream form mixed with thyme oil was prepared for EDA recording. Our groups were formed as EDA recording gel (Group 1), cream with thyme oil (Group 2), cream containing 10% boron (Group 3) and cream containing 30% boron (Group 4). In each group, 3 months old, 10 male rats were used, and creams were applied to the soles of the hind extremities of the rats, EDA was recorded from this region after half an hour, and skin conductivity levels (SCL) were recorded as tonic (at rest) and phasic (with auditory sound stimulation). Results: EDA results recorded in the morning were analysed with tonic and phasic recordings. In the morning SCL measurements, tonic SCL value of Group 4 was higher than the other groups (P < 0.001). Although the phasic SCL value was measured, it was significantly higher in Group 4 than in all groups (P < 0.0s). Conclusion: EDA measurements showed that boron increased sweat gland activity by increasing sympathetic nerve activity.

Nevus apocrino puro: una entidad raramente sospechada / Pure apocrine nevus: a rarely suspected entity

Los nevus apocrinos puros son hamartomas de las unidades pilosebáceas caracterizadas por proliferaciones benignas de glándulas apocrinas maduras, la cual es una descripción microscópica realizada en los reportes de patología sin que se nombre el diagnóstico exacto. Considerando además, los diagnósticos diferenciales clínicos y la baja frecuencia de este diagnóstico, presentamos un caso clínico y una revisión del tema

Pure apocrine nevi are hamartomas of the pilosebaceous units characterized by benign proliferations of mature apocrine glands, which is a microscopic description made in pathology reports without the exact diagnosis being named. Considering the clinical differential diagnoses and its low frequency, we present a case report and a review of the literature on this topic

Separate extraction of human eccrine sweat gland activity and peripheral hemodynamics from high- and low-quality thermal imaging data.

Sweat gland activity and peripheral hemodynamics, which characterize the function of sympathetic cholinergic nerve fibers and the manifestation mechanisms of vascular tone regulation, respectively, can be detected via dynamic thermography of the skin. Thus, they are useful parameters for diagnosing various forms of neuropathy and functional circulatory disorders. Both parameters affect the dynamics of the skin temperature; therefore, for an adequate description of thermographic data, it is necessary to build models that consider both these coexisting components simultaneously. PURPOSE: The objective of this study was to determine the spatiotemporal and statistical features of dynamic thermograms of skin areas with sweat glands and to develop methods for the extraction of temperature components mediated by sweat gland activity (Tsweat) separately from hemodynamics (Tblood) based on thermograms of high and low temperature resolutions. METHODS: To separate the Tsweat and Tblood components, simultaneous thermographic and photoplethysmographic (PPG) measurements were performed in the area of the fingers during a deep inspiratory gasp (DIG). PPG data, which were obtained solely by hemodynamics, were converted into a temperature signal (Tblood) using the spectral filtering approach. By calculating the difference between the skin (Tskin) and blood (Tblood) temperature components, the Tsweat component was determined, which characterizes sweat gland activity and the integrity of the cholinergic sympathetic nerve fibers that innervate them. The Tsweat component was compared with the active sweat pore count curve, which was determined by the adaptive detection of local temperature minima. Thermographic and PPG measurements were performed for 3 min on a group of 15 volunteers during the DIG test. The skin temperature was measured using a cooled thermal imaging camera in the spectral range of 8-9 µm with a temperature sensitivity of 0.02 °C. PPG measurements were performed using a reflectance sensor with a central wavelength of 800 nm. Wavelet analysis with the Morlet basis function was used to preliminarily determine the spectrum of spontaneous temperature oscillations in an area of the skin with and without sweat pores. Statistical parameters of the histogram, such as the standard deviation and the statistical pore activation index (SPAI) - which is proposed in this paper were used in the DIG test to detect sweat gland activity with low-temperature resolution thermograms. The temporal dynamics of the statistical parameters were compared with the dynamics of the sweat pore count. RESULTS: The Tsweat component was correlated with the sweat pore count on the thermogram with a coefficient of 0.75, confirming the dependence of this temperature component on the sweat gland activity and the need for considering this activity in the analysis of the spatiotemporal dynamics of the human skin temperature. The use of the proposed SPAI and standard deviation allows the detection of sweat gland activity even with thermograms of a low temperature resolution. The use of an integrated map of the sweat gland activity will help the specialist to assess the degree of integrity of the innervation of skin areas in a single image. The primary assessment of the spectrum of temperature oscillations at rest indicated that spontaneous sweat gland activity is accompanied by high-frequency oscillations in the skin temperature localized in the area of sweat pores, within the frequency range of 0.07-0.3 Hz. This suggests the possibility of spectral separation of the temperature component mediated by sweat gland activity from the hemodynamic component, which dominates in the region of <0.1 Hz. The proposed two-component approach for the analysis of skin temperature dynamics allows separate assessment of sympathetic innervation and rhythms of hemodynamic regulation using dynamic thermograms.