Skin Areas Research Articles

Synthesis, characterization, and application potential of chitosan/acrylamide composite hydrogels as skin expanders

Hydrogels are currently widely used in regenerative medicine and wound repair due to their superior biocompatibility, reliable mechanical strength, and good morphological memory. We aimed to prepare a self-expanding hydrogel that can be used as a skin expander for the repair of large soft skin tissue defects. Self-expanding hydrogels were prepared by chemical cross-linking, which consisted of water-soluble chitosan (CS), acrylamide (AM), methylene bisacrylamide (NMBA), etc. Five groups of in vitro experiments, including (CS-AM) of 0% (pure AM group), 13.9%, 27.8%, 41.7%, and 55.6%, were conducted to determine mechanical properties, swelling properties, cytotoxicity, etc. In the rat model, both a tight skin area (neck) and a loose skin area (back) were selected for expansion with hydrogels. A total of 27.8% of the CS-AM samples expanded stably under the skin of the rats, achieving 370% expansion in the tight zone and 490% expansion in the flaccid zone. Subcutaneous histopathological examination suggested that the inflammation index of the pericolloid tissue was lower in the CS-AM group than in the pure AM group. Our results demonstrate that self-expanding CS-AM hydrogels have great potential for application as skin expanders.Graphical

Therapeutic Potential of Hydrogen as a Radioprotective Agent for the Prevention of Radiation Dermatitis

Radiation dermatitis (RD) is a common side effect in patients receiving radiotherapy. Currently, clinical skincare approaches for acute RD vary widely among institutions and lack consensus. Hydrogen molecules, acting as radioprotective agents by selectively scavenging free radicals, have the potential to protect against RD. In this study, we demonstrate that hydrogen reduces double-strand breaks, mitochondrial depolarization, and inflammatory cytokines induced by irradiation damage in HaCaT cells. Furthermore, in vivo experiments reveal that exposing irradiated skin areas to a hydrogen gas environment alleviates RD. Assessment of skin appearance grade and histology staining revealed that direct transdermal application of hydrogen can prevent radiation-induced follicle damage, dermal thickening, and leukocyte infiltration, thereby reducing the severity of RD. In addition, hydrogen enhances the skin’s antioxidant capacity, leading to a reduction in the Bcl-2-associated X protein/B-cell lymphoma 2 (Bax/Bcl-2) ratio, the number of apoptotic cells, and the expression of pro-inflammatory cytokines. Our data demonstrate that hydrogen possesses antioxidant, anti-inflammatory, and anti-apoptotic properties, and could be a preventive strategy for RD.

Potential Utility of Laser Speckle Contrast Imaging to Detect Early Microcirculatory Changes Associated With Erythema Nodosum in Crohn's Disease: A Case Report.

Lay Summary In this case report of a young female patient with Crohn’s disease, presenting with erythema nodosum, laser speckle contrast imaging was able to detect blood flow changes in the affected skin area before clinical signs of the skin lesion emerged.

Potential application of matrine microneedles for the treatment of atopic dermatitis in joint skin

Atopic dermatitis (AD) commonly manifests in skin areas subjected to flexion, particularly joints. This underscores the importance of dissolving microneedles (DMNs) used in AD treatment having strong skin adhesion to prevent drug delivery interruption due to patch detachment during patient activity. Moreover, matrine (MAT), a prominent active ingredient derived from the natural plant Sophora flavescens, is known for its significant efficacy in treating skin inflammation, itching, and allergic diseases. Herein, we presented MAT-loaded DMNs (MAT-DMNs) specifically tailored for joint skin application in AD treatment. MAT-DMNs can rapidly dissolve and hydrate after application, demonstrating adhesive properties on ex vivo pig skin, rat abdominal skin, and finger joint skin, thereby ensuring sustained and uninterrupted drug delivery to the skin. In vitro evaluations revealed that MAT-DMNs exhibited 24-hour first-order release profiles with cumulative penetration rates of 78.70 ± 4.24 % and 77.14 ± 6.65 % for the low-dose and high-dose groups, respectively. Furthermore, these DMNs showed excellent skin compatibility and therapeutic efficacy in AD mice models. Specifically, the skin lesion score in MAT-DMNs group was significantly lower (2.67 ± 0.40) compared to the model group (11.60 ± 1.62) and the blank DMNs group (10.80 ± 1.67). MAT-DMNs effectively alleviated AD symptoms such as itching and inflammation by reducing epidermal thickening, decreasing mast cell infiltration, and lowering the expression of Th2 cytokines (IL-4 and IL-10) and pro-inflammatory factors (IL-1β, IL-6, and TNF-α) compared to the blank DMNs group (p < 0.01). These findings suggest that MAT-DMNs hold promise for clinical AD treatment, particularly for skin diseases commonly affecting joint areas.

Epidemiological Analysis of Psoriasis in China from 2020 to 2022.

Psoriasis is a persistent inflammatory skin condition driven by an immune response and influenced by both genetic and environmental factors. The high likelihood of disease recurrence has been a major concern for many patients, while the concurrent presence of other conditions has significantly impacted their quality of life. To improve early detection of and treatment for patients by studying the epidemiological characteristics of patients with psoriasis in China. The Psoriasis Real-World Big Data Collection Platform was initiated by the National Skin and Immune Diseases Clinical Medical Research Center (Beijing First Hospital of Peking University) in August 2020. During the period from August 2020 to June 2022, a total of 1012 hospitals across the nation participated in data entry. This article presents an epidemiological feature analysis based on the real case questionnaire survey form collected over the past 2 years. The prevalence of psoriasis is highest among young and middle-aged men, affecting largely the skin area. Factors such as smoking, obesity, and family history are likely to influence disease onset. In this study's data, the limbs and trunk were the most common sites for psoriasis onset, with cardiovascular disease being the most prevalent comorbidity. Topical corticosteroid creams are frequently used in treatment by Chinese patients, along with a notable proportion opting for oral Chinese medicine for systemic treatment. Secukinumab is the primary choice when utilizing biological agents. The actual data of patients with psoriasis from 2020 to 2022 offer crucial insights into the disease progression among the Chinese psoriasis population in recent years. Through an analysis of patient characteristics and treatment modalities, it furnishes valuable guidance for the prevention, early detection, and management of psoriasis.

Wound closure techniques after wide excision for hidradenitis suppurativa: a systematic review and meta-analysis.

Hidradenitis suppurativa (HS) is a chronic inflammatory disease that affects intertriginous skin areas, clinically characterized by recurrent inflamed nodules, abscesses, sinus tracts, and severe scars. Systemic treatments may provide temporary relief, while wide surgical excision offers prolonged disease-free periods. We evaluated the most efficient wound closure methods following wide excision of HS lesions in terms of recurrence, functionality, and quality of life. A systematic literature search was conducted in PubMed, Embase, Cochrane, and ClinicalTrials.gov, adhering to the PRISMA 2020 criteria. We included original studies published until February 2024, focusing on wound closure methods post-wide excision for HS. Data from 121 papers were analyzed using network and direct meta-analysis methods to compare recurrence and postoperative complication rates. From 1181 articles, 121 were included in the meta-analysis after removing duplicates and excluding publications that did not meet the inclusion criteria. Recurrence rates were associated with the type of reconstruction technique as follows: primary closure, 25% (95% confidence interval [CI], 20-30%); skin grafts, 18% (95% CI, 14-22%), and flaps, 12% (95% CI, 9-15%). Secondary intention healing showed a recurrence rate of 28% (95% CI, 23-33%). Flaps were associated with the lowest recurrence rates compared to other surgery techniques.

Comprehensive evaluation of skin exposure to PBDEs and PCBs in diverse South China populations via dermal wipe sampling.

This study analyzed skin wipe samples from the forehead, palm, forearm, and lower leg of 120 volunteers across different age groups-preschoolers, thresholders, middle-aged, and elderly-with each group comprising 30 individuals with a balanced sex ratio from a city in South China. The research aimed to assess the occurrence, concentration, and associated health risks of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) adsorbed onto human skin from environmental sources. We identified 13 PBDE congeners and 10 PCB congeners across all samples, with average detection frequencies of 48% for PBDEs and 16% for PCBs, with concentrations ranging from non-detectable (ND) to 4200 and ND to 2300ng/m2, respectively. Skin concentrations of both PBDEs and PCBs decreased in the order of face > hand > arm > shank (ANOVA, P < 0.001), suggesting higher exposure to uncovered skin areas than to those covered by clothing, regardless of age or sex. The daily average dose of dermal (DADderm) and oral (DADoral) for PBDEs spanned from 7.0 × 10-4-0.19ng/kg/d and ND-15 ng/kg/d, respectively, whereas the PCB exposure doses ranged from ND-7.8ng/kg/d (DADderm) and ND-2.0ng/kg/d (DADoral), respectively. Preschool children displayed notably higher DADoral levels than the other groups (P < 0.0001), which was attributed to their more frequent hand-to-mouth activity. Preschool boys exhibiting a higher DADderm (P < 0.05) and both preschool boys and university women showing elevated DADoral levels (P < 0.01 and P < 0.05, respectively). Health risk assessments concluded that the carcinogenic risks from BDE209 and PCBs were within acceptable limits (10-4) for all sampled populations.

Photogallery. Fungal lesions of skin and nails infections in HIV-associated immunodeficiency

Against the background of any immunodeficiency, including that caused by HIV infection, the risk of developing superficial and invasive fungal diseases increases. Among people living with HIV, the most common fungal skin lesions are candidiasis, rubromycosis, and pityriasis versicolor. As immunosuppression worsens in HIV-positive patients not on antiretroviral therapy, the frequency and severity of mycoses increases. Thus, rubromycosis can spread beyond the feet, covering large areas of skin; sometimes the smooth skin of the hands, large folds, and areas of long hair growth are affected. In this case, the peripheral inflammatory ridge along the edge of the lesions, characteristic of rubromycosis, is sometimes absent. According to some reports, over half of patients in the secondary disease stage of HIV infection suffer from onychomycosis. The progression of the disease often occurs in a short time. In addition to the nail plates of the feet, the nails on the hands are often affected. In patients with HIV infection who do not receive antiretroviral therapy, difficult-to-treat onychomycosis occurs. Cryptococcosis is an opportunistic mycosis caused by yeast-like fungi Cryptococcus spp. It usually develops in HIV-positive individuals with a CD4+ T-lymphocyte level of less than 100 cells/μl. Skin lesions are usually secondary and indicate cryptococcal dissemination. Dermatological manifestations of cryptococcosis are varied. These may include papules and nodules surrounded by erythema and prone to ulceration, vesicular, pustular, herpetiform, acne-like rashes, ulcerative-necrotic lesions. We present to your attention a photogallery of cases of fungal skin lesions that developed against the background of HIV-associated immunosuppression.

Essential Considerations for Radiologists in Diagnosing Hidradenitis Suppurativa.

Hidradenitis suppurativa, also referred to as inverse acne, manifests as a persistent inflammatory skin disorder characterized by lesions such as deep nodules, abscesses, sinus tracts, and fibrotic scars. These manifestations predominantly occur in skin folds and intertriginous areas, notably in the axillary, inguinal, perianal, perineal, and inframammary regions. Due to similarities with other conditions in its initial stages, accurate diagnosis of hidradenitis suppurativa is often delayed, sometimes spanning several years. Diagnosis relies on identifying specific morphologic features (such as deep, inflamed, and painful nodules; sinus tracts; and scars), considering the affected sites (skin folds and areas with apocrine glands), and recognizing the chronic nature of the condition (persistent course with periods of exacerbation and remission). There are no definitive biologic or pathologic diagnostic tests, and biopsy of the affected area is not necessary. Treatment varies based on severity and may include topical and systemic antibiotics, hormonal therapy, immunomodulators, and surgery. Due to associated pain, increased site sensitivity, secretion drainage, odor, and scarring, this condition can have a negative psychosocial impact. Imaging studies, including high-frequency US and MRI with subsequent three-dimensional reconstruction, serve as valuable tools for precise staging, monitoring disease activity, and preoperative assessment. Currently, high-frequency US stands as the preferred method, incorporating sonographic classifications, while MRI and thee-dimensional imaging represent an emerging and promising approach. Imaging helps identify the extent of sinus tracts, assess involvement dimensions in advanced disease stages, and monitor proposed treatments. ©RSNA, 2024 Supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article.

Preclinical safety assessment in rats after dermal exposure to acetylcarvacrol, a potential acaricide against the brown dog tick

Carvacrol, a phenolic monoterpene found in essential oils of plants of the Lamiaceae family, emerges as an alternative acaricide of plant origin. Its acetylation was proposed to obtain a derivative compound with a better pharmacological profile and lower toxicity to non-target organisms. The present study aimed to assess the preclinical safety of acetylcarvacrol after dermal application in Wistar rats, through the examination of hematological and biochemical parameters, as well as histopathological analysis of the skin, liver and kidney. For this, twenty rats were distributed into four groups with five animals each. Three groups received treatment with different concentrations of the substance (26, 52, and 104 µL/mL) based on the lethal concentration for Rhipicephalus sanguineus ticks, and one group (Control) received only the vehicle. Acetylcarvacrol was applied daily to a trichotomized skin area for 21 days. No changes in hematological parameters were observed. Regarding biochemical analysis, a slight increase in urea and alanine transaminase levels was noted. No significant changes were observed in the kidney and liver, although the rats had developed cumulative irritant contact dermatitis at the application site, as corroborated by the histopathological analysis of the skin. In general, the results showed that the dermal application of acetylcarvacrol in the experimental conditions described here is safe. However, it can cause signs of mild systemic toxicity and skin irritation at high concentrations, suggesting that this product should be used in lower therapeutic doses and that the development of less aggressive formulations, including the combination with other acaricides, is desirable.

Perioperative Observation and Nursing of a Child with Facial Venous Malformation Treated with Interventional Embolization

&amp;lt;i&amp;gt;Background&amp;lt;/i&amp;gt;: Venous malformations (VMs) are a rare disease with an incidence of only about 1/10,000 in children, but VMs can expand as the child grows, appearing more in shallow skin areas such as the neck of the head, can cause discomfort or degradation, and therefore, can seriously affect the physical and mental health of the child. There are numerous treatment options for VMs, and interventional embolosclerotherapy has become the clinically preferred treatment for VMs due to its many advantages. &amp;lt;i&amp;gt;Case Presentation&amp;lt;/i&amp;gt;: We summarize the perioperative care experience of a 10-year-old child with severe right facial malformation diagnosed as facial venous malformation (VMs) who underwent interventional embolization during hospitalization. After 14 days of careful treatment and nursing by medical staff, the child was discharged successfully. &amp;lt;i&amp;gt;Discussion&amp;lt;/i&amp;gt;: The key points of our perioperative care for this patient include paying attention to the mental health of the child and providing psychological support; strengthening health education and paying attention to the prevention of falls; preoperative preparation; intraoperative care; observation of the condition; pain assessment and care; strengthening discharge guidance; and doing a good job in continuous nursing. &amp;lt;i&amp;gt;Conclusion&amp;lt;/i&amp;gt;: For the nursing of the child with facial venous malformations, it is necessary to pay attention not only to their physiological care but also to their psychological care to help them recover as soon as possible.

Microbial imbalance in Darier disease: Dominance of various staphylococcal species and absence of Cutibacteria

Darier disease (DD) is a rare autosomal dominant genodermatosis characterized by erythematous papules and plaques mainly involving sebaceous areas, such as the face, chest and back. Skin microbiome plays an essential role in maintaining skin homeostasis. A disturbed skin microbiome may contribute to the exacerbation of DD. We investigated the bacterial composition of two predilectional sites in DD patients and healthy individuals. We also measured the microbiome composition of deeper skin layers, where diversity was significantly reduced compared to the superficial layer of the skin from the same area. The microbiome of DD patients at lesional sites differed from that of non-lesional skin areas; moreover, non-lesional sites were different from those of the controls. Lesional areas were dominated by Staphylococcus species, such as S. aureus, S. epidermidis, S. hominis, S. sciuri, and S. equorum. However, levels of Cutibacterium acnes (formerly Propionibacterium acnes) and C. acnes subspecies defendens were significantly lower in lesional sites than in non-lesional sites. A significant decrease was measured in the levels of these two bacteria between non-lesional and control samples. Our findings may indicate that alterations in the skin microbiome could contribute to the inflammation of skin lesions in DD.

The development of the external genitals in female human embryos and foetuses. Part 2: Vaginal vestibule, anal canal, perineal raphe and perineal cutaneous muscles.

Concomitant with the rupture of the cloacal membrane, the perineal skin epithelium thickens (see accompanying article). In this study, we establish in female embryos and foetuses that the thick skin area divides into ventral and dorsal areas at ~14 weeks and gradually becomes restricted to the vaginal vestibule and anal canal thereafter. The dense mesenchymal core of the labia minora, which forms at ~8 weeks, extends dorsally to the anal canal as a midline reinforcement. The skin epithelium overlying this reinforcement is much thinner than the flanking 'thick skin', and is supported by an interrupted basement membrane, which implies epithelial-mesenchymal transformation of the thin midline epithelium and the subsequent establishment of the perineal raphe by the merging of the adjacent thick epithelium. Meanwhile, the anogenital distance in the perineum increases rapidly in length. Perhaps as a consequence, the labia minora cover only the ventral third of the vaginal vestibule at 20 weeks. The endodermal ducts of Bartholin's glands are identifiable at 7 weeks, while acini form at ~12 weeks. The vestibular bulbs become identifiable at ~10 weeks and form vascular networks after ~14.5 weeks. After the rupture of the cloacal membrane, the diameter of the junction of the dorsal cloaca with the anal canal is just a pinhole but widens dorsoventrally after the 7th week. The cutaneous muscles of the perineal area form as a ventrally open U-shaped mesenchymal mass, from which the anal sphincter and bulbospongiosus muscle develop. In conclusion, our findings show that thick skin epithelium persists in the vaginal vestibule and anal canal.

Number of Facial Hair Corresponds to Frequency of Spontaneous Face-Touch in Humans.

People all over the world, independent of their culture or background, touch their faces up to 800 times per day. No other part of the body is touched as often as the face. Forehead, nose, and chin-the so-called T-zone of the face-are touched particularly frequently during spontaneous facial self-touches (sFST). It is hypothesized that there is a relationship between the density of mechanoreceptors (inferred from facial hair distribution) and the frequency of spontaneous self-touching. In order to indirectly measure the density of mechanoreceptors (cutaneous end organ complexes), the number of vellus and terminal hairs at 40 different measuring points on the face of 30 (15f/15m) healthy volunteers in study A is determined. In study B, the frequency of sFST at the same 40 measuring points in 66 (32f/34m) healthy persons is determined. Study A reveals that the number of facial hairs-in both sexes-is higher in the T-zone than in other areas of the face. Study B reveals that the T-zone is touched more frequently than other areas of the face. Skin areas of the face with a higher number of vellus hairs (and presumably higher innervation density) are touched particularly frequently during sFST.

Diffuse reflectance spectroscopy and RGB-imaging: a comparative study of non-invasive haemoglobin assessment

Non-invasive assessment of haemoglobin (Hb) level in blood is a hot spot in the point-of-care biomedical diagnostics. Several optical methods are suggested as a solution, some of them being approved for clinical use. Still, there is no consensus on the accuracy of optical techniques, the quality of Hb assessment on different tissue sites, and on the ability of combined use of several optical techniques to improve the quality of Hb level prediction. In this work we examined the capabilities of two optical techniques—diffuse reflectance spectroscopy and RGB-imaging of the skin and fingernails areas—in detecting low blood Hb level. The test sample consisted of 240 adult volunteers with 70 volunteers exhibiting Hb level lower than 120 g/L. We show that using simple descriptors of the diffuse reflectance spectrum of the forearm skin and fingernails is applicable for predicting low blood Hb concentration (ROC-AUC = 0.84 ± 0.08), while RGB-imaging shows similar performance when applied to the fingernail areas (ROC-AUC = 0.83 ± 0.07), which can be considered perspective for clinical use and screening properties. We also report that while the joint use of predictions from two optical methods slightly improves the accuracy of non-invasive Hb level assessment (ROC-AUC = 0.86 ± 0.07), the effect is not as high as one might expect from combining predictions of truly independent modalities, indicating the limit of the accuracy one can expect with multimodal optical approach. We review this case and propose possible solutions towards more sensitive non-invasive optical determination of hemoglobin.

Сравнительный анализ методов диагностики состояния органа дыхания у экспериментальных животных

Summary. The purpose of the study is to comparison of methods for diagnosing the state of the respiratory organ of experimental animals under the influence of physical factors, the intensity and exposure times of which are close to extreme. Materials and methods of research. The experiments used 45 male rabbits of the “Soviet Chinchilla” breed with a body weight of 2,7-3,4 kg, randomly divided into a control group, a group exposed to the lungs, a group exposed to the hearing organ and a group exposed to thermal effects on different areas of skin. To differentiate structural and functional disorders of the external respiratory system, three methods for diagnosing the state of the respiratory organ of experimental animals (rabbits) were used: acoustic impedance measurement of the respiratory tract, analysis of biophysical parameters of the lungs and pathological examination. A general conclusion about the state of the respiratory organ was given on the basis of a comparative statistical analysis of the characteristics of animals in the experimental and control groups. The relative size of the area of hemorrhages on the pleural surface of the lungs was used as a criterion indicator. The results of the study and their analysis. It has been shown that methods for diagnosing the state of the respiratory system based on impedance, biophysical indicators and the results of a pathological examination complement each other, providing an objective diagnosis of the state of the respiratory organ of experimental animals under the influence of physical factors, the intensity and exposure times of which are close to extreme, and are comparable in objectivity (sensitivity and diagnostic specificity) with methods used in medical clinical practice (impulse oscillometry).

Human bare and clothing-covered skin exposure to chlorinated paraffins for the general populations: Exposure pattern differential and significance of indirect dermal exposure via clothing-to-skin transport

To investigate human exposure to short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) through dermal and oral intake via hand-to-mouth contact, wipes from the face, forearm, hand, and foot of 30 volunteers were sampled. The concentration of ∑SCCPs and ∑MCCPs ranged from 0.66 to 119 and 0.71 to 565 µg/m2, respectively. Hands exhibited significantly higher ∑CPs concentrations than other skin areas, indicating that direct contact with indoor surfaces contributed considerable CP levels on this bare skin area. Gender differences in CP levels were observed in wipes from all locations, except for the hands, possibly because of the significant variability in residuals on the hands. A significant positive relationship was found between CP levels on the hands and faces, and the CP ratios of the hands/faces were related to log KOA. Bare skin showed more significant variations in CP partitioning among related congeners and between genders than skin covered by clothing, as elucidated by the linear analysis of RSD and log KOA. Although concentrations on clothing-covered areas were relatively lower than on bare skin, the median estimated dermal absorption doses of ∑SCCPs and ∑MCCPs (152 and 737 ng/kg bw/day, respectively) for the entire body were approximately 1–2 orders of magnitude higher than those for oral ingestion (1.62 and 7.94 ng/kg bw/day, respectively), emphasizing indirect dermal uptake as a significant exposure pathway for humans.

Disentangling the spinal mechanisms of illusory heat and burning sensations in the thermal grill illusion.

The thermal grill illusion (TGI), a phenomenon in which the juxtaposition of innocuous warm and cold temperatures on the skin elicits a burning sensation, offers a unique perspective to how pain occurs in response to harmless stimuli. We investigated the role of the spinal cord in the generation of the TGI across 2 experiments (total n = 80). We applied heat and cold stimuli to dermatomes, areas of skin innervated by a single spinal nerve, that mapped onto adjacent or nonadjacent spinal segments. Enhanced warm and burning ratings during the TGI were observed when cold and warm stimuli were confined within the same dermatome. Furthermore, we found the spatial organisation of warm and cold stimuli within and across dermatomes affected TGI perception. Perceived warmth and burning intensity increased when the cold stimulus projected to the segment more caudal to the warm stimulus, whereas perceived cold during the TGI decreased compared with the opposite spatial arrangement. This suggests that the perception of TGI is enhanced when cold afferents are projected to spinal segments positioned caudally in relation to those receiving warm afferents. Our results indicate distinct interaction of sensory pathways based on the segmental arrangement of afferent fibres and are consistent with current interpretations of the spread and integration of thermosensory information along the spinal cord.

Alpha-Bisabolol-Loaded Cosmetic Micellar Solution with Cleansing and Antimicrobial Action for Facial Skin Hygiene

The current research is focused on the discovery and optimization of an effective cosmetic carrier of alpha-bisabolol as a first step in the development of a cosmetic product with cleansing and antimicrobial action for facial skin hygiene. A micellar solution of Poloxamer 407 was selected as a cosmetic base because of the good washing ability, easy application, and high tolerability of this polymeric surfactant. The solubilization capacity of a 5% micellar solution with respect to α-bisabolol was investigated by applying varying solubilization techniques and increasing concentrations of the oily active substance. The test samples were subjected to an accelerated physical stability test, viscosimetry, dynamic light scattering (DLS), electrophoretic light scattering (ELS), foamability test, and antimicrobial screening. Over the course of this research, the advantage of the film-hydration method over direct solubilization was demonstrated by the narrower size distribution and smaller hydrodynamic size of the micellar nano-carriers (ranging from 29.02 to 116.5 nm) and the respective higher physical stability of the dispersions. The optimized composition was found to be suitable for application on large skin areas in terms of viscosity in the temperature range from 20 °C to 40 °C (3.4–2.3 mPa.s). Preservation of the washing capacity of the micellar solution in the presence of solubilized α-bisabolol was established. The active composition demonstrated inhibitory activity against Staphylococcus aureus and Escherichia coli and fungicidal activity against Candida albicans. This study concludes that the optimal concentration of α-bisabolol to be solubilized in a 5% Poloxamer 407 micellar solution by the film-hydration technique is 1%, considering the desirable physical endurance and antimicrobial activity.

Microcirculatory Dysfunction in Patients With Diabetes Mellitus Detected by a Distributed System of Wearable Laser Doppler Flowmetry Analysers.

The paper is devoted to the study of perfusion and amplitude-frequency spectra of laser Doppler flowmetry (LDF) signals in patients with diabetes mellitus (DM) in different skin areas of the upper and lower extremities using a distributed system of wearable LDF analysers. LDF measurements were performed in the areas of the fingers, toes, wrists and shins. The mean perfusion values, the amplitudes of blood flow oscillations in endothelial, neurogenic, myogenic, respiratory and cardiac frequency ranges, and the values of nutritive blood flow were analysed. The results revealed a decrease in tissue perfusion and nutritive blood flow in the lower extremities and an increase in these parameters in the upper extremities in patients with DM. A decrease in the amplitudes of endothelial and neurogenic oscillations was observed. The obtained results confirm the possibility of using wearable LDF analysers to detect differences in the blood flow regulation in normal and pathological conditions.