Dermoscopy in Mycobacterium marinum infection and its correlation with clinical and histopathological features: a prospective observational study.

BACKGROUND: Mycobacterium marinum is a nontuberculous mycobacterium and a conditional pathogen to humans, which can be inoculated directly and cause chronic skin granulomas. Dermoscopy has been applied to other granulomatous skin diseases, but not to M. marinum infection. AIM: To explore the dermoscopic features of M. marinum infection, and its correlation with clinical and histopathological features. METHODS: In total, 27 lesions from 27 patients (19 women, 8 men, age range 28-71 years) diagnosed with M. marinum infection were identified by clinical examination, histopathological results, PCR sequencing and mycobacterial culture in the dermatology outpatient department of our hospital from March 2020 to February 2022. The dermoscopy images and pathological characteristics were analysed. RESULTS: Lesions were located on the hands, forearms and upper arms. The following dermoscopic features were observed: yellowish-orange structureless areas (85·2%), white striped structures (59·3%), follicular plugs (29·6%), yellowish oval clods (14·8%) and reddish or pinkish areas (14·8%). Vessel structures were visible in all cases: long hairpin vessels (81·5%), corkscrew vessels (25·9%), comma-shaped vessels (22·2%) and linear vessels (22·2%). CONCLUSION: Yellowish-orange structureless areas, white striped structures and long hairpin vessels are the most common dermoscopic features of M. marinum infection. Thus, dermoscopy could be used as a noninvasive auxiliary diagnostic method to provide a diagnostic basis for this disease.

Detection of skin thickness and density in healthy Chinese people by using high-frequency ultrasound.

OBJECTIVES: Due to a recent development of high-frequency ultrasound (HFUS) systems, it is easier to realize high-resolution in vivo imaging of the biological tissues. The object of this study was to map the thickness and echo density of skin layers in healthy Chinese people and assess the influence of gender, age, and region on it. METHODS: A total of 189 volunteers (85 male, 104 female) with age range of 22-75-year old (mean age of 41.2-year old) were enrolled. The thickness and density of the epidermis and dermis layer were detected by high-frequency (22 or 75 MHz) ultrasonography at 13 different anatomical sites, including the forehead, cheeks, flexor and extensor forearms, flexor and extensor upper arms, inner and outer legs, inner and outer thighs, back, and abdomen. RESULTS: The thickness and density of epidermis/dermis between different anatomical sites were statistically significant (p < 0.05). The epidermis thickness of the face and trunk were less than that of the limbs, whereas the thicknesses of the dermis were on the contrary. The density of the epidermis/dermis of the face and trunk were less than that of the limbs. The thickness of dermis in most of the sites were higher in male than in female, and the density of epidermis and dermis in most of the sites were less in men than in women. The thicknesses/densities of dermis were lower in older age group in almost all sites, whereas only several sites reached statistical. The difference between the north and south regions showed the environment also influenced the thickness and density of the skin. CONCLUSION: HFUS provides a simple noninvasive method for evaluating the skin thickness and echo-density, which, reflecting intradermal structure, exhibit systematic regional variation. With the establishment of Chinese phenotypic database of skin thickness and density, it will be helpful for the skin disease assessment, skin surgery, and cosmetology technology.

Comparison of dermoscopy and reflectance confocal microscopy accuracy for the diagnosis of psoriasis and lichen planus.

BACKGROUND: Dermoscopy and reflectance confocal microscopy (RCM) as noninvasive tools are gaining increasing importance in the diagnosis of inflammatory skin disorders. The purpose of our study was to calculate and compare the diagnostic accuracy of dermoscopy and RCM in common inflammatory skin diseases. MATERIALS AND METHODS: We retrospectively collected clinical, dermoscopic, and RCM images of psoriasis and lichen planuscases from March 2018 to February 2021 in China-Japan Friendship Hospital. There were 10 experts evaluated dermoscopic and RCM images independently. Sensitivity, specificity, positive predict value, and negative predictive value for each and all investigators were calculated. The diagnostic accuracy was also measured by the area under the curve (AUC) for the Receiver Operator Characteristic (ROC) Curves. RESULTS: We collected 82 psoriasis and 47 lichen planus cases. Dermoscopy was more sensitive than RCM in the diagnosis of psoriasis, and overall diagnostic accuracy of dermoscopy was also higher than RCM measured by AUC (0.879 vs. 0.835, p = 0.0001). For lichen planus, RCM had higher sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy than dermoscopy (AUC 0.916 vs. 0.813, p<0.0001). CONCLUSION: Dermoscopy and RCM play a significant role in assisting the diagnosis of psoriasis and lichens planus. These two noninvasive diagnostic tools have their own advantages and disadvantages for the evaluation of different inflammatory skin diseases, and they can be combined in clinical practice to improve the accuracy of the diagnosis of inflammatory skin diseases.

A novel method for fabrication of coated microneedles with homogeneous and controllable drug dosage for transdermal drug delivery.

Over the years, scientists have been focused on the development of microneedle coating process to coat a broad range of therapeutic agents onto the surface of the solid microneedles for effective drug delivery. The precise dose control, content uniformity as well as large-scale production of coated microneedles are still the core issues that have been the interest of researchers in this topic. To this end, a repeatable method that involved a micro-molding process was demonstrated for mass fabrication of coated microneedles with homogeneous and controllable drug loading under mild conditions. In this system, the dissolvable drug carriers with precise dosage were first mounted onto the solid microneedles and then exposed to the high moisture condition to finally obtain the coated microneedle with uniform and precise drug loading. Using the microneedle molds with the volume of 4.71 nL, 8.24 nL, 10.47 nL, and 12.56 nL per cavity, the drug loadings were precisely controlled at 4.8 ng, 6.4 ng, 9.3 ng, and 13.5 ng per needle, with the standard deviation of 0.09, 0.01, 0.07, and 0.53%, respectively. Mechanical property tests showed that the coated microneedles are strong enough for reliable skin insertion, and with in vivo trials in diabetic mice, we further confirmed the similar hypoglycaemic effect of insulin-coated microneedles to subcutaneous injection. Taken together, the micro-molding-based fabrication process has practical merits in the mass production of coated microneedles with homogeneous and controllable drug loading, facilitating the clinical translation of the microneedle technique.

An update on microneedle-based systems for diabetes.

Diabetes is one of the most serious chronic diseases today. Patients with diabetes need frequent insulin injections or blood sampling to monitor blood glucose levels. The microneedles are a painless transdermal drug delivery system, which has great advantages in achieving self-management. There have been a lot of researches on microneedles used in diabetes treatment. Microneedle-based treatment of diabetes has also changed from a simple and reliable system to a complex and efficient system. This review introduces microfluidic, glucose response, and other contents based on microneedles, and some challenges in the development of microneedles.

Dissolving microneedle rollers for rapid transdermal drug delivery.

Dissolving microneedle patch (DMNP) is a minimally invasive and painless self-administration device. However, due to skin deformation, it is difficult to apply it on the large areas of skin or curved skin as the patch size increased for DMNP. Here, we propose a polyvinyl alcohol (PVA)-based dissolving microneedle roller (DMNR) device that can be used for delivering drugs rapidly on the large surface areas or curved skin and does not need to be attached on the skin all the time during drug delivery. The hypoglycemic effect of insulin-loaded DMNRs for transdermal delivery of insulin was studied on the type 1 diabetic rat models. It was found that the insulin-loaded DMNR has an immediate and effective hypoglycemic effect that the blood glucose level reduced below to 50% of original blood glucose at 1 h after DMNRs administrated.

Skin diseases in the Da Qing Diabetes Study: a cross-sectional study.

BACKGROUND: The prevalence of skin diseases and diabetes mellitus (DM) are prominent around the world. The current scope of knowledge regarding the prevalence of skin diseases and comorbidities with type 2 DM (T2DM) is limited, leading to limited recognition of the correlations between skin diseases and T2DM. METHODS: We collected 383 subjects from the Da Qing Diabetes Study during the period from July 9th to September 1st, 2016. The subjects were categorized into three groups: Normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and T2DM. The prevalence and clinical characteristics of skin diseases were recorded and investigated. RESULTS: In this cross-sectional study, 383 individuals with ages ranging from 53 to 89-year-old were recruited. The overall prevalence of skin diseases was 93.5%, and 75.7% of individuals had two or more kinds of skin diseases. Additionally, there were 47 kinds of comorbid skin diseases in patients with T2DM, of which eight kinds of skin diseases had a prevalence >10%. The prevalence of skin diseases in NGT, IGT, and T2DM groups were 93.3%, 91.5%, and 96.6%, respectively; stratified analysis by categories showed a statistically significant difference in "disturbances of pigmentation" and "neurological and psychogenic dermatoses". The duration of T2DM also significantly associated with the prevalence of "disturbances of pigmentation" and "neurological and psychogenic dermatoses". Subsequently, the prevalence of "disturbances of pigmentation" was higher in males than females in NGT (P < 0.01) and T2DM (P < 0.01) groups. In addition, the difference in the prevalence of "disturbances of pigmentation" was also significant in NGT and T2DM groups (P < 0.01). CONCLUSIONS: There was a high prevalence of skin diseases in the Da Qing Diabetes Study. To address the skin diseases in the Da Qing Diabetes Study, increased awareness and intervention measures should be implemented.

Improved imiquimod-induced psoriasis like dermatitis using microneedles in mice.

Psoriasis is a chronic inflammatory skin disease, in which the key features are epidermis hyperplasia, hyper-keratinization, leading to low drug absorption. As an approach of transdermal drug delivery, the microneedle (MN) has received increasing attentions for its painless penetration and efficient administration. In this study, we fabricated polylactic acid polymer MNs with hot-press method and established a psoriasis-like skin inflammation model in ear and dorsal skin of mice by topical application of imiquimod (IMQ). The dynamometer and insertion test of MNs into parafilm and skin of mice were done, revealing that the MNs have sufficient mechanical properties to insert parafilm and skin of mice. The two methods (apply calcipotriol (CAL) directly and pre-treat with MNs before applying CAL) were used to treat psoriasis and observe the skin inflammation, including skin and epidermal thickening, spleen weight gain, inflammatory cell infiltration, and expression of inflammatory cytokines of TNF-α. Both methods have a therapeutic effect and the effect of the MN pretreatment group is better. In addition, there are statistical differences between the two groups (P < 0.05). These features indicated that the MNs may be promising in future clinical applications in improving the imiquimod-induced psoriasis like dermatitis.

In vivo safety assessment, biodistribution and toxicology of polyvinyl alcohol microneedles with 160-day uninterruptedly applications in mice.

Dissolving microneedles (DMNs) are widely used in drug delivery systems since they are based on one-step application, which is simple and convenient for patients, especially for the patients such as diabetes who need daily or long-term self-administration. In general, the matrix materials of DMNs are water-soluble materials that can release the encapsulated drugs gradually by dissolving in the skin without generating sharp needle waste. However, the matrix materials of DMNs will also leave in the skin after application. Thus, it is vital to evaluate whether the matrix material of DMNs dissolved in the skin will cause health risks such as toxicity to the body or some skin-related complications to patients who frequent or long-term administration. In this work, PVA, as one of the typical matrix materials of DMNs, was selected to prepare the DMNs to research the safety of PVA-based MNs to the body after being dissolved in the skin. Briefly, in a 160 - days trial, the healthy mice were daily administrated by PVA MNs. The results showed that PVA materials mainly accumulated in the skin tissues of mice after dissolving and the concentration of PVA in the insertion sites gradually decreased and was almost undetectable at 6 days after administration. The observation of general conditions, blood hematological analysis and histological examinations of the mice demonstrated that the PVA-based MNs do not cause appreciable toxicity to the healthy mice after daily insertion in a 160 - days trial. Altogether, these results encourage further studies of PVA MNs for biomedical applications and support translation of PVA-based DMNs from pre-clinical development into clinical trials.

Diagnostic capacity of skin tumor artificial intelligence-assisted decision-making software in real-world clinical settings.

BACKGROUND: Youzhi artificial intelligence (AI) software is the AI-assisted decision-making system for diagnosing skin tumors. The high diagnostic accuracy of Youzhi AI software was previously validated in specific datasets. The objective of this study was to compare the performance of diagnostic capacity between Youzhi AI software and dermatologists in real-world clinical settings. METHODS: A total of 106 patients who underwent skin tumor resection in the Dermatology Department of China-Japan Friendship Hospital from July 2017 to June 2019 and were confirmed as skin tumors by pathological biopsy were selected. Dermoscopy and clinical images of 106 patients were diagnosed by Youzhi AI software and dermatologists at different dermoscopy diagnostic levels. The primary outcome was to compare the diagnostic accuracy of the Youzhi AI software with that of dermatologists and that measured in the laboratory using specific data sets. The secondary results included the sensitivity, specificity, positive predictive value, negative predictive value, F-measure, and Matthews correlation coefficient of Youzhi AI software in the real-world. RESULTS: The diagnostic accuracy of Youzhi AI software in real-world clinical settings was lower than that of the laboratory data (P < 0.001). The output result of Youzhi AI software has good stability after several tests. Youzhi AI software diagnosed benign and malignant diseases by recognizing dermoscopic images and diagnosed disease types with higher diagnostic accuracy than by recognizing clinical images (P = 0.008, P = 0.016, respectively). Compared with dermatologists, Youzhi AI software was more accurate in the diagnosis of skin tumor types through the recognition of dermoscopic images (P = 0.01). By evaluating the diagnostic performance of dermatologists under different modes, the diagnostic accuracy of dermatologists in diagnosing disease types by matching dermoscopic and clinical images was significantly higher than that by identifying dermoscopic and clinical images in random sequence (P = 0.022). The diagnostic accuracy of dermatologists in the diagnosis of benign and malignant diseases by recognizing dermoscopic images was significantly higher than that by recognizing clinical images (P = 0.010). CONCLUSION: The diagnostic accuracy of Youzhi AI software for skin tumors in real-world clinical settings was not as high as that of using special data sets in the laboratory. However, there was no significant difference between the diagnostic capacity of Youzhi AI software and the average diagnostic capacity of dermatologists. It can provide assistant diagnostic decisions for dermatologists in the current state.