The dose response of erythemal area and intensity on the unprotected skin fits well to a logistic 3P model in SPF tests of a Chinese population, which has the potential to improve the precision and consistency of minimal erythema dose determination.

BACKGROUND: The current ISO guidelines for minimal erythema dose (MED) determination require assessment of erythema area of UV-irradiated skin sites. However, this parameter has not been adequately quantified in daily practice. The aims of this study were to investigate the dose response on the unprotected skin sites by quantifying the erythema area and intensity and to show the potential for improving the precision and consistency of MEDu determination by developing predictive models. METHODS: Standard radiation tests were conducted on the back of 31 healthy Chinese volunteers and the MEDu site of each subject was clinically determined by dermatologists. Images of test sites were captured 24 h after radiation, and the erythema area (%EA) and intensity (∆a*) were measured by image analysis. The data were fitted to a logistic 3P function to obtain dose-response curves, and a set of logit (inverse-logistic) models were then derived. An erythema area threshold of %EA = 52% was established to predict MEDu based on the clinical endpoints defined by ISO 24444:2019. RESULTS: Analysis of the clinically determined MEDu sites revealed wide ranges of %EA (62.3 ± 15% SD) and ∆a* (2.96 ± 0.92 SD). The dose response fitted well to a logistic 3P model (mean R2 = 0.965 and 0.975 for %EA and ∆a*, respectively). Applying the area threshold, values of MEDu were determined by the logit model for the test population, which significantly improved the consistency of MEDu determination (52 ± 0% SD and 2.73 ± 0.61 SD for %EA and ∆a*, respectively). CONCLUSION: This study demonstrated that the dose response of UV-induced erythema can be quantified and modeled once the erythema area and intensity are measured. The results of this study show the potential to improve the precision and consistency of MEDu determination in an SPF test. The similar potential in photodermatological, therapeutic, and diagnostic applications was also implied.

"One-step" characterization platform for pathogenic genetics of Staphylococcus aureus.

Staphylococcus aureus (S. aureus) is an important human pathogen causing a variety of life-threatening diseases. In recent years, the health problem caused by S. aureus contaminated food has become a global health problem. S. aureus can express various pathogenic factors, mainly used for adhesion, colonization, invasion and infection of the host. Therefore, rapid and accurate detection of virulence genes in S. aureus is necessary to prevent outbreaks caused by this pathogen. PCR is a useful tool for rapid detection of foodborne pathogens. The objective of this study was to detect the presence of major toxin genes in S. aureus, including sea, seb, sec, see, pvl and tsst, by using a PCR plate. Of the 13 strains tested, 12 (92.3%) were found to be positive for one or more toxin genes. This study realized the one-step detection of main toxin factors in S. aureus.

Study on the virulome and resistome of a vancomycin intermediate-resistance Staphylococcus aureus.

Methicillin-resistant S. aureus (MRSA) has been considered a potential "Super Bugs", responsible for various infectious diseases. Vancomycin has been the most effective antibitic to treat MRSA originated infections. In this study, we aimed at investigating the genomic features of a vancomycin intermediate-resistance S. aureus strain Guangzhou-SauVS2 isolated from a female patient suffering from chronic renal function failure, emphasizing on its antimicrobial resistance and virulence determinants. The genome has a total length of 2,605,384 bp and the G+C content of 33.21%, with 2,239 predicted genes annotated with GO terms, COG categories, and KEGG pathways. Besides the carriage of vancomycin b-type resistance protein responsible for the vancomycin intermediate-resistance, S. aureus strain Guangzhou-SauVS2 showed resistance to ß-lactams, quinolones, macrolide, and tetracycline, due to the acquisition of corresponding antimicrobial resistance genes. In addition, virulence factors including adherence, antiphagocytosis, iron uptake, and toxin were determined, indicating the pathogenesis of the strain.

Designing and Validating Autoverification Rules for Hematology Analysis in Sysmex XN-9000 Hematology System.

BACKGROUND: Hematology analysis is a common test among patients in hospital. However, manual verification of hematology analysis is time consuming and tedious, with variation between inter-individual laboratory workers. This study was to establish and validate a set of autoverification rules for hematology analysis in the department of laboratory medicine, Zhongshan Hospital of Sun Yatsen University. METHODS: Hematology analysis was measured by a Sysmex XN-9000 hematology system in the Department of Laboratory Medicine, Zhongshan Hospital of Sun Yatsen University. SYSMEX Laboman EasyAccess 6.0 and the laboratory information system were used to construct the algorithm and design the autoverification rules of hematology analysis according to Clinical and Laboratory Standards Institute document Auto 10A and 41 rules of Hematology Review Criteria. The laboratory turnaround time (TAT), autoverification pass rates, false positive, false negative, and the average error rate were verified after implementing autoverification rules. RESULTS: Approximate 1,300 specimens were collected daily and transferred to our laboratory for hematology analysis; that is necessary to build a database and to design autoverification rules. The average autoverification passing rate was 81%; the false positive rate was 13.6%; the false negative rate and the average error rate was nearly zero, indicating that incorrect reports were almost eliminated. Moreover, since implementing autoverification, the TAT was reduced by 27.0% in in-patient reports, by 21.9% in out-patient reports, and by 39.0% in emergency reports, which enhanced the productivity in our laboratory. CONCLUSIONS: Our laboratory accelerated verification and decreased TAT and the odds of human review errors in the released results since implementing the autoverification. Thus, we can save more time and concentrate on verifying the abnormal results and processing emergency tests.

High-flux simultaneous screening of common foodborne pathogens and their virulent factors.

Rapid and sensitive detection techniques for foodborne pathogens are important to the food industry. However, traditional detection methods rely on bacterial culture in combination with biochemical tests, a process that typically takes 4-7 days to complete. In this study, we described a high-flux polymerase chain reaction (PCR) method for simultaneous detection of nine targeted genes (rfbE, stx1, stx2, invA, oprI, tlh, trh, tdh, and hlyA) with multiplex strains. The designed primers were highly specific for their respective target gene fragments. As the selected primers follow the principles of similar melting and annealing temperature, all the targeted genes could be detected for one strain with the same PCR program. Combining with 96-well PCR plate, by adding a single different gene to each well in each row, both the ATCC strains (E. coli, Salmonella spp., V. parahaemolyticus, L. monocytogenes, P. aeruginosa, S. aureus) and the clinical strains (E. coli, P. aeruginosa, S. aureus) were simultaneously detected to carry their specific and virulence genes. Therefore, using 96-well PCR plate for PCR amplification might be applied to high-flux sequencing of specific and virulence genes.

Helios but not CD226, TIGIT and Foxp3 is a Potential Marker for CD4+ Treg Cells in Patients with Rheumatoid Arthritis.

BACKGROUND/AIMS: Rheumatoid arthritis (RA) is a progressive, chronic, even disabling systemic autoimmune disease. Imbalance between pathogenic immune cells and immunosuppressive cells is associated with the pathogenesis and development of RA and other autoimmune diseases. As Foxp3 is also expressed on activated CD4+ cells in the presence of inflammation, the identification of Treg cells in patients with RA remains a challenge. METHODS: Comprehensive analyses were carried out by Flow cytometry. Expression of Helios, CD226, T cell immunoreceptor with Ig and ITIM domains clinical samples and healthy controls. RESULTS: We have systemically examined three potential markers, Helios, CD226 and TIGIT, that are possibly related to Treg identification, and found that Helios expression on CD4+Foxp3+cells was decreased and negatively correlated with the disease activity of RA patients, while CD226 and TIGIT both showed elevated expression levels in CD4+Foxp3+cells in RA patients and they were not associated with disease activity of RA patients. CONCLUSION: Taken together, our findings indicate that CD4+CD25hiCD127low/-Foxp3+Helios+ may represent the real Treg cell population in patients with RA.

The Regulating Role of SB216763 in Pseudomonas aeruginosa Keratitis.

BACKGROUND: Glycogen synthase kinase 3 beta (GSK3b) is a multifunctional molecule, which plays a critical role in the regulation of various signaling pathways including cell proliferation, growth and development, and inflammation. However, whether GSK3b is involved in the pathological process of Pseudomonas aeruginosa keratitis remains unknown. METHODS: First, western blots were performed to measure the phosphorylated level of GSK3ß at Ser9 (inactive form) in an animal model of Pseudomonas aeruginosa keratitis. Second, the keratitis model received the GSK3ß inhibitor SB216763, and the inflammation of cornea was evaluated by clinical scores and slit photos. The expressions of inflammatory cytokines were assessed by real-time PCR, and the corneal bacterial burden was determined by plate count. RESULTS: The phosphorylated level of GSK3ß at Ser9 in the cornea markedly decreased after Pseudomonas aeruginosa infection. The inhibition of GSK3ß by SB216763 significantly ameliorated the progress of corneal disease and alleviated corneal opacity. SB216763 suppressed the expression of inflammatory cytokines IL-6 and IL-1b, but exhibited no effects on TNF-a and IL-10 expression. SB216763 dramatically decreased cornea bacterial burden at 5 days after infection with Pseudomonas aeruginosa. CONCLUSIONS: The activity of GSK3b was enhanced in Pseudomonas aeruginosa keratitis. The inhibition of GSK3ß by SB216763 promoted host resistance against Pseudomonas aeruginosa keratitis, via down regulating inflammatory cytokines and bacterial burden.

Minimal erythema dose, minimal persistent pigment dose which model for whitening products evaluation is better?

BACKGROUND/AIMS: How to select a suitable method in whitening products evaluation is still under discussion. Here, we compared two different artificial pigmentation models and explored an ideal UV dosage for skin whitening products evaluation model establishment. METHODS: Thirty five healthy volunteers with type IV human skin were recruited and the skin minimal erythema dose (MEDs) and minimal persistent pigment dose (MPPDs) were measured. All volunteers were simultaneously exposed to six increasing doses of radiations from different ultraviolet sources on lower back bilateral flattening area: 95% UVA/5% UVB with the radiating doses of 0.75, 0.94, 1.17, 1.46, 1.83, 2.29 MEDs was used on the left side; meanwhile 99% UVA/1% UVB with radiating doses of 6.0, 7.5, 9.4, 11.7, 14.6, 18.3 MPPDs were used on the right side. Observations and pigmentation measurements were carried out before and after UV radiation for 24 weeks. RESULT: 1.83 MED and 2.29 MED induced medium depth pigmentation by 95% UVA/5% UVB irradiation. 1.83 MED dose causing minimal photo-damage on skin was selected as the most suitable dose. With 99% UVA/1% UVB irradiation, 9.4 MPPD and 11.7 MPPD induced medium depth pigmentation. 9.4 MPPD dose causing minimal photo-damage on skin was selected. CONCLUSION: These findings potentiate advanced understanding of UV model establishment and selection for skin whitening products evaluation as related to dermatopharmacology and dermatotoxicology.

Efficacy and safety of 2% supramolecular salicylic acid compared with 5% benzoyl peroxide/0.1% adapalene in the acne treatment: a randomized, split-face, open-label, single-center study.

BACKGROUND: Topical drugs for mild to moderate acne include adapalene (ADA) and benzoyl peroxide(BPO). Supramolecular salicylic acid (SSA), a modified SA preparation, is considered as a new effective therapeutic scheme. OBJECTIVES: To compare the safety and efficacy of 2% supramolecular SA (2% SSA) with 0.01% adapalene plus 5% benzoyl peroxide (5%BPO +0.1%ADA) for treatment of facial acne. MATERIALS AND METHODS: This was an open-label, split face, randomized and single-centre clinical trial. Subjects with mild to moderate acne were enrolled. Two percent SSA cream were randomly applied on one side of the face while 5%BPO +0.1%ADA gel was applied on the opposite side for 28 days. The numbers of acne lesions, along with side effects of the targeted area were evaluated by the investigators at day 0, day 14, and day 28. Skin water content, TEWL and skin lightening indexes were measured at the same time. RESULTS: A total of 31 of acne patients completed the trial. Dates showed that 2% SSA had similar effects to 5%BPO +0.1%ADA in reducing papules/pustules (47.9% vs. 49.8%), non-inflammatory lesions (43.1% vs. 42.7%) and total lesions (44.1% vs. 45.6%; all p > 0.05) at day 28. The skin barrier (skin hydration value and TEWL value), skin brightness (L* value) and erythema (a* values) indicators showed no statistical differences in the left and right sides of the face (p > 0.05). CONCLUSION: This study demonstrated that 2% SSA has a similar efficacy with 5%BPO +0.1%ADA in mild to moderate acne treatment. This might be a useful pilot study that could be used to support further larger clinical trials.

Detection on integron carried gene cassettes from pathogens by loop mediated isothermal amplification assays.

In this study, a number of frequently detected gene cassettes from bacterial integrons have been detected and characterized by rapid and simple loop-mediated isothermal amplification (LAMP) assays. Six gene cassettes commonly found in class 1 integrons were studied, including dfrA12, dfrA17, aadA2, aadA5, orfF, and blaVIM2. Primers design, sensitivity, specificity, optimization of each LAMP assay, as well as application of the developed 6 individual LAMP assays on a large scale of bacteria, had been conducted. The optimal amplification was obtained with temperature as 65 °C, reaction time span as 45 min and volume as 25 µl. For application, 272 isolates with various gene cassettes yielded expectable positive amplicons and other 685 integron-negative bacteria showed negative results for the LAMP assays, totaling 100% detection rate and specificity.

Study on the excision and integration mediated by class 1 integron in Enterococcus faecalis.

Recognized as a mobile genetic element, integron is correlated to the excision and integration of exogenous genes, especially bacterial resistance genes. However, most of the investigations focused on Gram-positive bacteria with few exceptions. In this study, Enterococcus faecalis was selected to investigate the excision and integration of class 1 integron. A total of eight plasmids were subjected to establish the transformants for excision and integration test. As results showed, positive excision assay was observed, which had been confirmed by the further integration assays and PCR amplification. The observation of class 1 integron mediated excision and integration of various exogenous antibiotics resistance genes should raise the attention of integrons as novel antibiotic resistance determinant in Gram-positive bacteria, especially in Enterococcus.

First report of novel genetic array aacA4-blaIMP-25-oxa30-catB3 and identification of novel metallo-ß-lactamase gene blaIMP25: A Retrospective Study of antibiotic resistance surveillance on Psuedomonas aeruginosa in Guangzhou of South China, 2003-2007.

Carbapenem, imipenem and meropenem have been broadly prescribed contributing to the global occurrence and prevalence of carbapenem resistance in Psuedomonas aeruginosa, and the associated resistance genotypes remains clinically significant. A retrospective surveillance had been conducted on 499 P. aeruginosa isolates in South China during 2003-2007, including antimicrobial resistance and characterization of MBLs on carbapenem-resistant strains. One hundred and sixty-four out of 499 strains were carbapenem-resistant, with 11, 4 and 5 strains positive for blaIMP-9, blaIMP-25 and blaVIM-2, respectively. Sixteen out of 20 isolates were positive for intI1 and contained identical flanking regions (as indicated in KM384735), and all tested isolates containing the qacE△1-sul1 of the typical 3'-conserved region. A novel blaIMP-25 metallo-ß-lactamase and a genetic array of aacA4-blaIMP-25-oxa30-catB3 have been discovered from this retrospective surveillance on antimicrobial resistance of P. aeruginosa.

Trichophyton rubrum conidia modulate the expression and transport of Toll-like receptor 2 in HaCaT cell.

Trichophyton rubrum (T. rubrum) represents the most important agent of dermatophytosis in humans. T. rubrum infection causes slight inflammation, and tends to be chronic and recurrent. It is suggested that T. rubrum can modulate the innate immune responses of host cells, which result in the failure of host cells to recognize T. rubrum and initiate effective immune responses. In this study we show how T. rubrum conidia modulate the expression and transport of Toll-like receptor 2 in HaCaT cell. Flow cytometric analysis showed that the surface and total expression of Toll-like receptor 2 were upregulated at the very early stage when keratinocytes were exposed to T. rubrum conidia regardless of the dose, and the upregulation of surface TLR2 was much more significant than that of total TLR2. Moreover, TLR2 expression was suppressed after upregulation in the initial stage of T. rubrum exposure, and the decrease of total TLR2 was earlier than that of surface TLR2. Our results suggest that in the early stage, TLR2 of keratinocytes were upregulated and transported to the cell surface. After then, the expression of TLR2 was suppressed by T. rubrum conidia.

Clinical evidence on the efficacy and safety of an antioxidant optimized 1.5% salicylic acid (SA) cream in the treatment of facial acne: an open, baseline-controlled clinical study.

BACKGROUND/PURPOSE: Acne pathogenesis is multifactorial and includes inflammation. Combining active ingredients targeting multiple components of acne pathogenesis may yield optimal outcomes. This study investigates the safety and efficacy of an antioxidant optimized topical salicylic acid (SA) 1.5% cream containing natural skin penetration enhancers in combination with antioxidant activity for treatment of facial acne. METHODS: A total of 20 patients with facial acne, aged 19-32 years (2 males, 18 females; mean age 26.1 ± 3.2), were enrolled. Patients were treated with topical 1.5% SA cream and instructed to apply the cream as a thin film over the affected area twice daily (in the morning and evening) for 4 weeks. Inflammatory severity, numbers of papules and pustules were evaluated by investigators at day 0 and weekly, and patients ranked their improvement. RESULTS: In all, 95% of patients improved: 20% had complete clearing, 30% had significantly improved, 15% had moderate improvement, 30% had mild improved, and there was no response in 5% of the patients by 4 weeks of treatment. No side effects were observed. CONCLUSION: This study demonstrates the efficacy and safety of this optimized topical 1.5% SA cream containing natural skin penetration enhancers in combination with antioxidant activity when applied twice daily for the reduction of facial acne; in particular, it is most effective for mild-to-moderate acne.

Antimicrobial Resistance, SCCmec, Virulence and Genotypes of MRSA in Southern China for 7 Years: Filling the Gap of Molecular Epidemiology.

As the prevalence of Staphylococcus aureus infections is of worldwide concern, phenotype and genotype in prevalent MRSA strains require longitudinal investigation. In this study, the antibiotic resistance, virulence gene acquisition, and molecular type were determined on a large scale of nosocomial S. aureus strains in Southern China during 2009-2015. Bacterial identification and antimicrobial susceptibility to 10 antibiotics were tested by Vitek-2. Virulence genes encoding staphylococcal enterotoxins (SEA, SEB, SEC, SED, and SEE), exfoliative toxins (ETA and ETB), Panton-Valentine leukocidin (PVL), and toxic shock syndrome toxin (TSST) were detected by PCR, with SCCmec typing also conducted by multiplex PCR strategy. Genotypes were discriminated by MLST and spaA typing. MLST was performed by amplification of the internal region of seven housekeeping genes. PCR amplification targeting the spa gene was performed for spa typing. No resistance to vancomycin, linezolid, or quinupristin and increase in the resistance to trimethoprim/sulfamethoxazole (55.5%) were identified. A total of nine SCCmec types and subtypes, thirteen STs clustered into thirteen spa types were identified, with ST239-SCCmec III-t037 presenting the predominant methicillin-resistant S. aureus (MRSA) clone. Typically, SCCmec type IX and ST546 were emergent types in China. Isolates positive for both pvl and tsst genes and for both eta and etb genes were also identified. Important findings in this study include: firstly, we have provided comprehensive knowledge on the molecular epidemiology of MRSA in Southern China which fills the gap since 2006 or 2010 from previous studies. Secondly, we have presented the correlation between virulence factors (four major groups) and genotypes (SCCmec, ST and spa types). Thirdly, we have shown evidence for earliest emergence of type I SCCmec from 2012, type VI from 2009 and type XI from 2012 in MRSA from Southern China.

A new product of multi-plant extracts improved skin photoaging: An oral intake in vivo study.

BACKGROUND: Besides the topical application of cosmetics, nutraceuticals represent a promising strategy for preventing skin photoaging and skin cancers. METHODS: To determine the effect of a new multi-plant extracts product containing Cucumis melo extract, acerola extract, olive fruit, aloe vera gel, grape seed extract, and lycopene, a randomized, placebo-controlled, double-blind clinical trial and an ultraviolet (UV)-induced murine photoaging model were deployed. 55 healthy subjects aged 45-60 were enrolled and randomized to take the product or placebo orally for 12 weeks. Skin aging and whitening indexes were measured with non-invasive techniques. 90 Balb/c mice aged 7-8 weeks were randomly divided into six groups: normal, UV, UV+vehicle, UV+different doses of the product (0.500 g/kg.BW, 0.250 g/kg.BW, 0.125 g/kg.BW, respectively). Except the normal group, mid-dorsal regions were irradiated with UVA+UVB for 8 weeks. Factors of oxidative stress, tyrosinase, and histological analysis of the mid-dorsal skin were determined. RESULTS: In the clinical trial, the TEWL, hydration, sebum, elasticity, and the L*, a*, melanin index change from baseline, ITA° were significantly improved in the experiment group. In the animal experiment, compared to the UV+vehicle group, UV+high dose group showed significantly lower malondialdehyde (MDA) and tyrosinase, but higher superoxide dismutase (SOD), total antioxidant capacity (T-AOC), and glutathione peroxidase (GSH-Px). The UV+moderate dose group showed significant improvement of MDA and GSH-Px, and the UV+low dose group only showed improvement of GSH-Px. Histological photoaging manifestations were attenuated in the UV+high and moderate dose groups. CONCLUSIONS: The multi-plant extracts product improved skin photoaging possibly via antioxidant and anti-tyrosinase ways.

hMSC exosomes as a novel treatment for female sensitive skin: An in vivo study.

Background: Recent studies have reported that the incidence of sensitive skin is increasing. Skin sensitivity and skin barrier functions were related to many skin diseases including atopic dermatitis, psoriasis, rosacea, and so on. Mesenchymal stem cell (MSC)-derived exosomes (hMSC) might be considered as a new effective therapeutic scheme. Aims: This study aims to investigate the safety and efficacy of hMSC exosomes as a novel topical treatment for sensitive skin. Patients/Methods: Exosomes were extracted from primary hMSC via ultracentrifugation method. The morphology of hMSC exosomes was studied via transmission electron microscope. Expression of exosome specific surface marker was detected via Western blot. 22 subjects (female, aged 18-55) diagnosed with sensitive skin were enrolled. Follow-up was conducted before, 7-day, 14-day, and 28-day after hMSC exosomes use. Transepidermal water loss (TEWL), surface hydration, sebum secretion, and L*a*b* value were simultaneously tested at the same time point in an environment-controlled room. Results: Under transmission electron microscopy, the extracted hMSC exosomes were circular or elliptical with intact membrane structure, and their diameters ranged mainly from 40 to 80 nm. Western blot showed that the expression of markers CD63, CD9, and Tsg101 was positive. Brownian motion based nanoparticle trajectory analysis (NTA) showed that the main peak of particle size distribution occurred around 96 nm, the average particle size was 122 nm, and the main peak accounted for 96.7%. All this conformed to the biological characteristics of exosomes standardized by the International Society for Extracellular Vesicles. In the clinical trial, scores of objective symptoms including roughness, scales, erythema, and subjective symptoms including tension, burning, or itching, were improved after 7-, 14-, and 28- day using hMSC-exosomes. TEWL, hydration, sebum, pH, and a* values were tended to return to the level of healthy skin. Conclusion: The hMSC-exosomes, with the advantages of biocompatibility and biodegradability, could improve clinical symptoms and eruptions in sensitive skin patients, and might be as an MSC cell-free novel therapy in sensitive skin-related disease treatment.

Verification and application of a modified carbapenem inactivation method (mCIM) on Pseudomonas aeruginosa: a potential screening methodology on carbapenemases phenotype in Bacillus cereus.

Antimicrobial resistance (AMR) has been a leading issue for human health globally threatening the achievement of several of the Sustainable Development Goals (SDGs). Originated from Bacillus cereus, carbapenemases phenotype has been considered to be a major concern in AMR. In this study, the AMR identification rate of P. aeruginosa isolates and infections in FAHJU showed an obvious upward trend from 2012 to 2016. All 88 carbapenem-resistant P. aeruginosa strains were screened for carbapenemase phenotype by modified Carbapenem Inactivation Method (mCIM), and these results of mCIM were compared with traditional PCR results. The isolates of P. aeruginosa and infected patients showed obvious upward trend from 2012 to 2016. The drug resistance to common clinical antibiotics was serious that the clinical rational use of antibiotics should be strengthened, which is in accordance with the Global Antimicrobial Resistance and Use Surveillance System (GLASS) report. In comparison, the results of mCIM showed that 18 out of 88 CRPA strains were carbapenemase positive, which were completely consistent with the results yielded by PCR method. Therefore, it is convinced that this mCIM methodology is a simple and quick method for detected carbapenemases producing P. aeruginosa and has a potential capability in carbapenemases phenotype of pathogen like B. cereus, which will undoubtedly aid in the AMR therapy.

Skin barrier damaging and repairing process: A new application field of dermoscopy.

BACKGROUND: Although more and more noninvasive detection technologies have been used in assessing skin barrier integrity and functions, more accurate, intuitive, and convenient detective methods still needed to be explored and developed. AIMS: To investigate the characteristic image changes under the dermoscopy and to explore the relationship with skin physiological indexes in skin barrier damaging and repairing process. PATIENTS/METHODS: 25 healthy subjects with normal skin in forearm were included and divided into different groups according to the operated strips numbers (30, 35, and 40 times). Before tape stripping, and immediately, 3, 7, 14, and 21 days after tape stripping, dermoscopic examination and skin transepidermal water loss (TEWL), surface hydration, and L*a*b* value were simultaneously tested in the same region. RESULTS: Immediately after different times tape stripping, the amount of cuticle cells residues and the microvascular images were different. In skin barrier repairing process, the scab forming time observed under dermoscopy was day 14, day 7, and day 3 on 30 times, 35 times, and 40 times stripped skin, respectively. A small amount of cuticle cells and blurry vessels could be identified in hydration value <40 group, while there was no cuticle cell residue, and the branching vessels were obvious in hydration value >40 group. CONCLUSIONS: Unique manifestations could be observed under dermoscopy in different time points of skin barrier with various degree of injury and in skin barrier repairing process. By combining dermoscopy and skin indexes assessing technologies, the skin barrier integrity and function could be observed and evaluated more accurately and precisely.

Substrate adaptation of Trichophyton rubrum secreted endoproteases.

Trichophyton rubrum is the most common pathogen caused the dermatophytosis of nail and skin in human. The secreted proteases were considered to be the most important virulence factors. However, the substrates adaptation of T. rubrum secreted proteases is largely unknown. For the first time, we use the keratins from human nail and skin stratum corneum as the growth medium to investigate the different expression patterns of T. rubrum secreted endoproteases genes. During grow in both keratin-containing media SUB7 and MEP2 were the highest expressed gene in each family. These results indicated that SUB7 and MEP2 may be the dominant endoproteases secreted by T. rubrum during host infection and the other proteases may play a supplementary role. The direct comparison of T. rubrum grown on skin and nail medium showed different substrate favorite of secreted endoproteases. The genes MEP2, SUB5, SUB2 and SUB3 were more active during growth in skin medium, possibly these proteases have a higher affinity for skin original keratins. While the structures of SUB1, SUB4, and MEP4 maybe more suitable for the degradation of nail original keratins. This work presents useful molecular details for further understanding the pathogenesis of secreted proteases and the wide adaptation of T. rubrum.