The causal relationship between blood metabolites and rosacea: A Mendelian randomization.

BACKGROUND: An increasing amount of research demonstrates that metabolic disorders are related to rosacea. However, the correlations and causal relationships among them remain unknown. METHODS: We conducted not only forward 2-sample MR (Mendelian randomization) analyses but also reverse MR analyses which showed positive results in the forward MR analysis. In the forward MR analyses, inverse-variance weighted (IVW) and MR-Egger were performed as MR analyses. Cochran's Q test and the MR-Egger Intercept were used for sensitivity analyses. Concerning reverse MR analyses, IVW, MR-Egger, weighted median, simple mode, and weighted mode were applied. Cochran's Q test, MR-Egger Intercept, and MR pleiotropy residual sum and outlier (MR-PRESSO) outlier test were applied as sensitivity analyses. RESULTS: A total of 24 metabolites and 1 metabolite ratio were shown to have a causal effect on rosacea. N-lactoyl phenylalanine (N-Lac-Phe) was estimated as statistically significant by Bonferroni correction. Interestingly, we found three metabolites that were negatively associated with rosacea, especially caffeine, which are in line with the results of a large cohort study of females. For reverse MR analysis, we revealed that rosacea could potentially decrease the generation of two metabolites: octadecenedioate (C18:1-DC) and methyl vanillate sulfate. CONCLUSION: This study identified blood metabolites that may be associated with the development of rosacea. However, the exact mechanism by which these positive metabolites influence rosacea remains uncertain due to the paucity of experimental investigations. The combination of genetics and metabolomics offers novel viewpoints on the research of underlying mechanisms of rosacea and has significant value in screening and prevention of rosacea.

Definition of refractory melasma and its treatment: a review.

Although patients with refractory melasma have been treated using various methods, there is still no precise definition or summary of the therapies. To define refractory melasma and conduct a review of the treatments, we searched for relevant publications in PubMed, Web of Science, and the Cochrane Library, and a total of 35 references were obtained. Refractory melasma can be roughly defined as an ineffective treatment for melasma, including topical bleaching agents, chemical peels, laser therapy, microdermabrasion for more than six months, or chemical peels treated more than six times. Meanwhile, physicians should be careful when treating patients with darker skin and dermal or mixed types of melasma since these individuals do not respond well to treatment. Lasers combined with other methods, especially different types of lasers or topical agents, are considered more effective than monotherapy. Oral tranexamic acid (TXA) is a prospective cure for refractory melasma. Other methods include a combination of chemical peels, microneedling, or injections with additional therapies. In conclusion, we were able to provide a rough definition of refractory melasma and list the available therapies. According to the literature, the most prevalent treatment is laser combination therapy. However, laser treatment should be considered only after topical agents and chemical peeling have failed. Considering its side effects, efficacy, and safety, oral TXA may be a better option, but more research is needed to make a firm conclusion. Moreover, maintenance therapy is required after treatment.

Neuropeptide S attenuates methamphetamine-induced stereotyped behavior in rats.

Effective therapies for Methamphetamine (METH) induced stereotyped behavior are still being explored. It is unclear whether Neuropeptide S (NPS) is involved in the mechanism of METH-induced stereotyped behavior. In the contemporary behavioral study, pretreatment with NPS reduces stereotyped circling significantly, but didn't have any impact on the total incidence of stereotypy and stereotyped sniffing and biting induced by METH (10 mg/kg). When METH (10 mg/kg) was administered to rats, the level of NPS in the cerebrospinal fluid was not affected, but pretreatment with NPS reversed METH-induced glutamate release in the hippocampus and striatum. The findings suggest that NPS receptor system is likely to involve in the METH-overdose-induced behaviors.

No Causal Effect of COVID-19 on Varicella-Zoster Infection, Herpes Zoster Progression, and Postherpetic Neuralgia: A Two-Sample Mendelian Randomization Study.

Purpose: Coronavirus disease (COVID-19) may trigger the reactivation of the latent varicella-zoster virus and may be a risk factor for herpes zoster (HZ). However, the causal relationship between COVID-19 and varicella-zoster infections remains controversial. This study aimed to estimate the causal inferences between COVID-19 and HZ. Methods: This study used a two-sample Mendelian randomization (MR) design. The inverse variance-weighted method was used as the primary method and sensitivity analyses were conducted, including the MR-Egger regression, weighted median and weighted mode. We searched at https://gwas.mrcieu.ac.uk/ using the keywords "COVID-19" for exposure data and "zoster" for outcome datasets. Results: We got 26 COVID-19 datasets and five zoster datasets. We used 26 COVID-19 datasets as exposure data corresponding to each zoster dataset for the MR analysis. There were nine datasets of COVID-19 where the number of SNPs was fewer than three in the MR analysis of the risk of HZ, varicella zoster virus (VZV) glycoprotein E and I antibody levels, anti-VZV IgG seropositivity, and post-zoster neuralgia. In addition, there were 10 datasets of COVID-19 where the number of SNPs was less than three in the MR analysis of anti-VZV IgG levels. The results of the MR analysis showed that all p-values were greater than 0.05. Sensitivity analysis revealed no evidence of horizontal pleiotropy in most two sample MR analyses. Conclusion: Our results indicate that there is no causal relationship between COVID-19 and varicella-zoster infection, HZ progression, and postherpetic neuralgia.

Quantitative detecting low concentration polystyrene nanoplastics in aquatic environments via an Ag/Nb2CTx (MXene) SERS substrate.

In this study, the plasmonic Ag nanoparticles (Ag NPs) were uniformly anchored on the high conductivity Nb2CTx (MXene) nanosheets to construct an Ag/Nb2CTx substrate for surface-enhanced Raman spectroscopy (SERS) detection of polystyrene (PS) nanoplastics. The KI addition (0.15 mol/L), the volume ratio between substrate colloid and nanoplastic suspension (2:1), and the mass ratio of Nb2CTx in substrate (14%) on SERS performance were optimized. The EM hot spots of Ag/Nb2CTx are significantly enlarged and enhanced, elucidated by FDFD simulation. Then, the linear relationship between the PS nanoplastics concentration with three different sizes (50, 300, and 500 nm) and the SERS intensity was obtained (R2 > 0.976), wherein, the detection limit was as low as 10-4 mg/mL for PS nanoplastic. Owing to the fingerprint feature, the Ag/Nb2CTx-14% substrate successfully discerns the mixtures from two-component nanoplastics. Meanwhile, it exhibits excellent stability of PS nanoplastics on different detection sites. The recovery rates of PS nanoplastics with different sizes in lake water ranged from 94.74% to 107.29%, with the relative standard deviation (RSD) ranging from 2.88% to 8.30%. Based on this method, the expanded polystyrene (EPS) decomposition behavior was evaluated, and the PS concentrations in four water environments were analyzed. This work will pave the way for the accurate quantitative detection of low concentration of nanoplastics in aquatic environments.

Construction of 2D/2D ZnIn2S4/Nb2CTx (MXene) hybrid with hole transport highway and active facet exposure boost photocatalytic hydrogen evolution.

In this study, leveraging the tunable surface groups of MXene, the two-dimensional (2D) Nb2CTx with OH terminal (NC) was synthesized. 2D ZnIn2S4 (ZIS) nanosheets were prepared with the aid of sodium citrate, enhancing the exposure ratio of active (110) facet. On this basis, 2D/2D ZnIn2S4/Nb2CTx heterojunctions were fabricated to improve photocatalytic hydrogen evolution reaction (HER) performance. The optimized 6 wt%Nb2CTx/ZnIn2S4-450 (6NC/ZIS-450) photocatalyt exhibits a remarkable HER rate of 3603 µmol g-1h-1, which is 10 times superior to that of the original ZnIn2S4. Its apparent quantum efficiency (AQE) at 380 nm reaches 14.9 %. Meanwhile, even after 5 rounds of HER, the activity of 2D/2D ZnIn2S4/Nb2CTx heterojunction remained at 90 %, far superior to that of pure ZnIn2S4 (34 % and 31 %). Energy band structure analysis and density functional theory (DFT) calculation indicate that Nb2CTx adsorbed with OH exhibit a low work function. By serving as a hole cocatalyst, it effectively boosts the photocatalytic HER rate of ZnIn2S4/Nb2CTx heterojunction and inhibits the photocorrosion of ZnIn2S4. This unique insight, via hole transport highways and increased exposure of active facets, effectively enhances the activity and stability of sulfides photocatalysts.