755-nm picosecond laser plus topical 20% azelaic acid compared to topical 20% azelaic acid alone for the treatment of melasma: a randomized, split-face and controlled trial.

PURPOSE: Melasma remains a refractory skin condition that needs to be actively explored. Azelaic acid has been used for decades as a topical agent to improve melasma through multiple mechanisms, however, there is a lack of research on its combination with laser therapy. This study evaluated the effectiveness of isolated treatment with topical 20% azelaic acid and its combination with 755-nm picosecond laser in facial melasma patients. METHODS: A randomized, evaluator-blinded, controlled study was conducted on 30 subjects with facial melasma in a single center from October 2021 to April 2022. All subjects received topical 20% azelaic acid cream (AA) for 24 weeks, and after 4 weeks, a hemiface was randomly assigned to receive 755-nm picosecond (PS) laser therapy once every 4 weeks for 3 treatments. Treatment efficacy was determined by mMASI score evaluations, dermoscopic assessment, reflectance confocal microscopy (RCM) assessments and patient's satisfaction assessments (PSA). RESULTS: Treatment with 20% azelaic acid, with or without picosecond laser therapy, significantly reduced the hemi-mMASI score (P < 0.0001) and resulted in higher patient satisfaction. Improvements in dermoscopic and RCM assessments were observed in both sides of the face over time, with no difference between the two sides. RCM exhibited better dentritic cell improvement in the combined treatment side. No patients had serious adverse effects at the end of treatment or during the follow-up period. CONCLUSION: The additional use of picosecond laser therapy showed no clinical difference except for subtle differences detected by RCM assessments.The study was registered in the Chinese Clinical Trial Registry (ChiCTR2100051294; 18 September 2021).

Investigation on the Awareness and Behavior of Primary School Students on Sunscreen Use in Beijing.

Objective: This study aims to understand primary school students' behavior and awareness of sun exposure and sunscreen in Beijing, China. Methods: A questionnaire survey was conducted of 232 students in grades 4-6 at a public primary school in Beijing, including 129 boys (55.6%) and 103 girls (44.4%). The contents of the questionnaire included awareness about ultraviolet rays, sun exposure, sunscreen habits, and the understanding and use of sunscreen. Results: The majority of the subjects (75.0%) said they had never been sunburned, and 26.3% had never been tanned. Only 7.3% of the primary school students had a comprehensive and correct understanding that sunlight will burn, cause cancer, tan, and age the skin. Sunscreen (47.8%), sunshades (47.4%), sun hats (44.4%), avoiding going out at noon (37.5%), and sunglasses (30.2%) were the most frequently used sunscreen means. Furthermore, 47.8% of primary school students used topical sunscreen for light protection, higher than other measures. The proportion of girls using sunscreen at least once a day was more than boys. Conclusion: Primary school students in Beijing, China, do not have a comprehensive understanding of ultraviolet rays, and there are deficiencies in protective behavior. Their awareness and use of sunscreen need to be improved.

Delayed complication of botulinum toxin and hyaluronic acid filler injections: A case report.

BACKGROUND: Botulinum toxin and hyaluronic acid (HA) filler injections are popular minimally invasive cosmetic procedures owing to their convenience, efficiency, and durability; however, adverse reactions often occur. MATERIALS AND METHODS: We describe the delayed hypersensitivity reaction that occurred after sequential injections of botulinum toxin and HA filler. RESULTS: The histopathologic and dermatoscopic findings suggested a delayed hypersensitivity reaction with the formation of a dermal foreign body granuloma. The rash resolved 2 months following treatment with antihistamines and topical steroids cream. CONCLUSION: We assume that local trauma during the blepharoplasty stimulated an immune response, which was the basis for this complication.

Laser therapy in the treatment of melasma: a systematic review and meta-analysis.

Melasma is a highly prevalent and cosmetically disfiguring pigmented skin disease. The post-treatment results are often unsatisfactory. A large number of clinical trials have tried to prove the effectiveness of the combination therapy involving laser therapy, but the results have been indeterminate. This study aimed to evaluate the effectiveness of laser treatment for melasma via a systematic review and meta-analysis. We respectively searched 4 databases and clinicaltrials.gov as of June 8, 2021. Two researchers independently searched for literature and extracted data. Study outcomes were computed by weighted mean differences (WMD). All statistical analyses were performed by the Review Manager version 5.3, STATA version 14 software at 95% confidence interval. We obtained 22 eligible studies which involved a total of 694 patients. After the heterogeneity test and sensitivity analysis, we took a subgroup meta-analysis on the before and after treatment of different laser types. We found that most lasers and laser-based combinations were associated with reduced melasma area and severity index (MASI), such as low-fluence Q-switch 1,064-nm Nd: YAG laser (QSNYL) (WMD: - 2.76; 95% CI: - 3.53 to - 1.99), fractional ablative CO2 laser (WMD: - 9.36; 95% CI: - 12.51 to - 6.21), and fractional ablative 2940-nm Er: YAG laser (WMD: - 2,72; 95% CI: - 3.94 to - 1.49). Significant decrease was seen in neither MASI score of non-ablative 1550-nm fractional laser (WMD: - 1.29; 95% CI: - 2.80 to 0.21) and picosecond laser (WMD: - 0.58; 95% CI: - 1.43 to 0.27), nor melanin index (MI) of low-fluence QSNYL treatment (WMD: 10.17; 95% CI: - 4.11 to 24.46). When using laser to treat melasma, various adverse reactions may occur, most of which will resolve quickly without subsequent treatment, such as edema, erythema, scaling, and burning sensation after treatment. However, for patients with darker skin, there are risks of postinflammatory hyperpigmentation and hypopigmentation. The laser and laser-based combination treatment for melasma could significantly reduce the MASI score, which was showed by our systematic review and meta-analysis.

Treponema pallidum-specific antibody expression for the diagnosis of different stages of syphilis.

BACKGROUND: Tp15, Tp17, Tp45, and Tp47 are outer-membrane proteins found in Treponema pallidum, the etiologic agent of syphilis. These proteins are potent antigens and are potential markers for the serological detection of syphilis. The present study analyzed antibodies to these protein antigens (TP-IgM and TP-IgG) in human serum and investigated the expression of these antibodies during different stages of syphilis. METHODS: Serum samples were collected from 69 subjects (male 45, female 24) diagnosed with syphilis and analyzed by Western blotting for the expression of IgM and IgG against the four protein antigens. Expression levels of the target antibodies were compared during the same stage of syphilis as well as between different stages of this disease. RESULTS: In subjects with primary syphilis, the positive rate of Tp45 IgM was higher than that of other TP-IgM. Tp15 IgM was detected only in subjects with tertiary syphilis. Similarly, the seroprevalence of Tp45 IgG in primary syphilis was higher than for other TP-IgG. No target TP-IgM was detected in subjects with latent syphilis. In subjects with secondary syphilis, the expression level of Tp15 IgG (138.73 ± 20.16) was higher than for other target TP-IgG. In subjects with tertiary syphilis, all target TP-IgG were detected. In subjects with tertiary or latent syphilis, the expression levels of Tp45 IgG (121.33 ± 11.04 and 110.10 ± 40.19, respectively) were higher than those of other target TP-IgG. The expression levels of all Tp-IgM were similar before or after anti-syphilis treatment. In comparison, the expression levels of all TP-IgG decreased compared with the pre-treatment levels, and this decrease was statistically significant (both P < 0.05) for Tp17 IgG and Tp47 IgG. CONCLUSIONS: After Treponema pallidum infection, Tp45 IgM appeared first and Tp15 IgM occurred during later stages. The positive rates of all TP-IgG increased with the duration of this disease. Anti-syphilis treatment reduced the expression levels of Tp17 IgG and Tp47 IgG. Larger-scale studies are required to further validate the value of Tp15, Tp17, Tp45, and Tp47 as markers for the early detection of primary and latent syphilis.

Recurrent antitopographic inhibition mediates competitive stimulus selection in an attention network.

Topographically organized neurons represent multiple stimuli within complex visual scenes and compete for subsequent processing in higher visual centers. The underlying neural mechanisms of this process have long been elusive. We investigate an experimentally constrained model of a midbrain structure: the optic tectum and the reciprocally connected nucleus isthmi. We show that a recurrent antitopographic inhibition mediates the competitive stimulus selection between distant sensory inputs in this visual pathway. This recurrent antitopographic inhibition is fundamentally different from surround inhibition in that it projects on all locations of its input layer, except to the locus from which it receives input. At a larger scale, the model shows how a focal top-down input from a forebrain region, the arcopallial gaze field, biases the competitive stimulus selection via the combined activation of a local excitation and the recurrent antitopographic inhibition. Our findings reveal circuit mechanisms of competitive stimulus selection and should motivate a search for anatomical implementations of these mechanisms in a range of vertebrate attentional systems.

Generating oscillatory bursts from a network of regular spiking neurons without inhibition.

Avian nucleus isthmi pars parvocellularis (Ipc) neurons are reciprocally connected with the layer 10 (L10) neurons in the optic tectum and respond with oscillatory bursts to visual stimulation. Our in vitro experiments show that both neuron types respond with regular spiking to somatic current injection and that the feedforward and feedback synaptic connections are excitatory, but of different strength and time course. To elucidate mechanisms of oscillatory bursting in this network of regularly spiking neurons, we investigated an experimentally constrained model of coupled leaky integrate-and-fire neurons with spike-rate adaptation. The model reproduces the observed Ipc oscillatory bursting in response to simulated visual stimulation. A scan through the model parameter volume reveals that Ipc oscillatory burst generation can be caused by strong and brief feedforward synaptic conductance changes. The mechanism is sensitive to the parameter values of spike-rate adaptation. In conclusion, we show that a network of regular-spiking neurons with feedforward excitation and spike-rate adaptation can generate oscillatory bursting in response to a constant input.