Explore the vast range of titles available.

Catalysts for chemical and electrochemical reactions underpin many aspects of modern technology and industry, from energy storage and conversion to toxic emissions abatement to chemical and materials synthesis. This role necessitates the design of highly active, stable, yet earth-abundant heterogeneous catalysts. In this Review, we present the perovskite oxide family as a basis for developing such catalysts for (electro)chemical conversions spanning carbon, nitrogen, and oxygen chemistries. A framework for rationalizing activity trends and guiding perovskite oxide catalyst design is described, followed by illustrations of how a robust understanding of perovskite electronic structure provides fundamental insights into activity, stability, and mechanism in oxygen electrocatalysis. We conclude by outlining how these insights open experimental and computational opportunities to expand the compositional and chemical reaction space for next-generation perovskite catalysts.

Blue nail discoloration is a distinctive clinical presentation, and diagnosis is challenging given the broad differential diagnosis. A comprehensive review of the literature describing blue discoloration of one or multiple nails was performed using the PubMed, Embase, Scopus, and Web of Science databases. A total of 245 publications were included and grouped based on involvement of a single nail (monodactylic) or multiple nails (polydactylic). Monodactylic blue discoloration was associated with tumors or benign nevi, most commonly glomus tumors, followed by blue nevi and less commonly melanomas. Polydactylic blue discoloration was frequently associated with medications (such as minocycline, zidovudine, and hydroxyurea), toxic and exogenous exposures (such as silver), and other medical conditions (such as HIV/AIDS and systemic lupus erythematous). Patients presenting with blue nail discoloration warrant a thorough history, physical examination, and workup to rule out malignancy, systemic disease, or toxic exposure. We present diagnostic algorithms for monodactylic and polydactylic blue nail discoloration to guide workup and treatment plans.

Nicotinamide has many well-established chemopreventive properties in protecting against ultraviolet-induced skin damage, mitigating inflammation, and reducing keratinocyte carcinoma (KC) development among immunocompetent individuals. Its effectiveness in immunosuppressed patients, however, is unclear. There is conflicting research on whether nicotinamide effectively decreases KCs in immunosuppressed solid organ transplant recipients (SOTRs). This study assesses the effectiveness of nicotinamide in the secondary prevention of KC in immunosuppressed patients. We conducted a retrospective cohort study in a single tertiary care institution. The primary outcome was KC incidence in the year before and after nicotinamide supplementation. Secondary outcomes included the incidence of invasive squamous cell carcinoma (SCC), SCC in situ (SCCis), and basal cell carcinoma (BCC) over one- and two-year intervals. All included patients had taken oral nicotinamide, 500 milligrams twice daily, for at least one year. A total of 47 SOTRs (74.5% male; mean age 65.2 years) were included in our retrospective cohort study. Of 81 patients initially screened, 34 were excluded due to inadequate follow-up, dermatologic care outside our institution, or early discontinuation of nicotinamide. At one year post-nicotinamide supplementation, total KC incidence decreased from 224 (78 SCC, 103 SCCis, 43 BCC) to 121 cases (40 SCC, 55 SCCis, 26 BCC), a mean reduction of 2.19 KCs (95% CI: −3.48 to −0.90; p  = 0.0012). Significant reductions were observed in SCC (mean decrease of 1.15; 95% CI: −1.78 to −0.52; p  = 0.00081) and SCCis (mean decrease of 1.37; 95% CI: −2.61 to −0.13; p  = 0.032). BCC reduction was not statistically significant ( p  = 0.13). In the 31 patients with two-year follow-up data, KC incidence declined from 234 to 167, a mean reduction of 2.18 KCs (95% CI: −4.18 to −0.14; p  = 0.037). Sensitivity analyses excluding patients on concomitant acitretin confirmed that reductions in total KC incidence maintained significance at both one-year and two-year intervals. Nicotinamide supplementation significantly decreased KC incidence in immunosuppressed SOTRs over the one-year and two-year intervals. We recommend nicotinamide as a low-risk, low-cost chemopreventive supplement for reducing KCs in SOTRs.

Introduction Nail changes are frequent clinical findings in patients with cutaneous psoriasis and psoriatic arthritis, often causing significant impairments in quality of life. Numerous targeted therapies have been previously studied for treatment of nail psoriasis, however, newer agents have not been captured in prior systematic reviews. With over 25 new studies published since 2020, the landscape of nail psoriasis systemic treatments is rapidly evolving, warranting analysis of recently approved therapies. Methods An updated systematic review of all PubMed and OVID database studies assessing efficacy and safety of targeted therapies for nail psoriasis was performed, with the goal of incorporating clinical data of recent trials and newer agents, namely brodalumab, risankizumab, and tildrakizumab. Eligibility criteria included clinical human studies reporting at least one of the nail psoriasis clinical appearance outcomes (Nail Psoriasis Severity Index, modified Nail Psoriasis Severity Index). Results A total of 68 studies on 15 nail psoriasis targeted therapeutic agents were included. Biological agents and small molecule inhibitors included TNF-alpha inhibitors (adalimumab, infliximab, etanercept, certolizumab, golimumab), IL-17 inhibitors (ixekizumab, brodalumab, secukinumab), IL-12/23 inhibitors (ustekinumab), IL-23 inhibitors (guselkumab, risankizumab, tildrakizumab), PDE-4 inhibitors (apremilast), and JAK inhibitors (tofacitinib). These agents all demonstrated statistically significant improvements in nail outcome scores, compared with placebo or with baseline values, at weeks 10–16 and weeks 20–26, with some studies assessing efficacy up to week 60. Safety data for these agents were acceptable and consistent with known safety profiles within these timepoints, with nasopharyngitis, upper respiratory tract infections, injection site reactions, headache, and diarrhea being the most reported adverse events. Specifically, the newer agents, brodalumab, risankizumab, and tildrakizumab, showed promising outcomes for treatment of nail psoriasis on the basis of current data. Conclusion Numerous targeted therapies have shown significant efficacy in improving nail findings in patients with psoriasis and psoriatic arthritis. Data from head-to-head trials have shown greater efficacy of ixekizumab over adalimumab and ustekinumab, as well as brodalumab over ustekinumab, while prior meta-analyses have demonstrated superiority of ixekizumab and tofacitinib to other included agents at various assessed timepoints. Further studies on the long-term efficacy and safety of these agents, as well as randomized controlled trials involving comparison with placebo arms, are needed to fully analyze differences in efficacy of newer agents compared with previously established therapies.

Utilization of telemedicine for dermatology has greatly expanded since the start of the COVID-19 pandemic, with over 500 new teledermatology studies published since 2020. An updated review on teledermatology is necessary to incorporate new findings and perspectives, and educate dermatologists on effective utilization. We discuss teledermatology in terms of diagnostic accuracy and clinical outcomes, patient and physician satisfaction, considerations for special patient populations, published practice guidelines, cost effectiveness and efficiency, as well as administrative regulations and policies. Our findings emphasize the need for dermatologist education, prioritization of reliable reimbursement systems, and technological innovations to support the continued development of teledermatology in the post-pandemic era.

Understanding the nature of active sites is central to controlling (electro)catalytic activity. Here we employed surface X-ray scattering coupled with density functional theory and surface-enhanced infrared absorption spectroscopy to examine the oxygen evolution reaction on RuO 2 surfaces as a function of voltage. At 1.5 V RHE , our results suggest that there is an –OO group on the coordinatively unsaturated ruthenium (Ru CUS ) site of the (100) surface (and similarly for (110)), but adsorbed oxygen on the Ru CUS site of (101). Density functional theory results indicate that the removal of –OO from the Ru CUS site, which is stabilized by a hydrogen bond to a neighbouring –OH (–OO–H), could be the rate-determining step for (100) (similarly for (110)), where its reduced binding on (100) increased activity. A further reduction in binding energy on the Ru CUS site of (101) resulted in a different rate-determining step (–O + H 2 O – (H +  + e − ) → –OO–H) and decreased activity. Our study provides molecular details on the active sites, and the influence of their local coordination environment on activity. Understanding the nature of active sites is central to controlling the activity of a given catalyst. This work combines operando characterization and computational techniques to examine the oxygen evolution reaction mechanism on RuO 2 surfaces.

Understanding the adsorption and oxidation of NO on metal oxides is of immense interest to environmental and atmospheric (bio)chemistry. Here, we show that the surface oxygen activity, defined as the oxygen 2 p -band centre relative to the Fermi level, dictates the adsorption and surface coverage of NO x and the kinetics of NO oxidation for La 1− x Sr x CoO 3 perovskites. Density functional theory and ambient-pressure X-ray photoelectron spectroscopy revealed favourable NO adsorption on surface oxygen sites. Increasing the surface oxygen activity by increasing the strontium substitution led to stronger adsorption and greater storage of NO 2 , which resulted in more adsorbed nitrogen-like species and molecular nitrogen formed upon exposure to CO. The NO oxidation kinetics exhibited a volcano trend with surface oxygen activity, centred at La 0.8 Sr 0.2 CoO 3 and with an intrinsic activity comparable to state-of-the-art catalysts. We rationalize the volcano trend by showing that increasing the NO adsorption enhances the oxidation kinetics, although NO adsorption that is too strong poisons the surface oxygen sites with adsorbed NO 2 to impede the kinetics. Understanding the mechanism for the catalytic conversion of NO x is crucial to develop superior greenhouse gas abatement schemes, although it remains challenging. Here, the authors reveal important aspects of the redox properties of NO x on a La 1– x Sr x CoO 3 perovskite by a combination of density functional theory calculations and ambient-pressure X-ray photoelectron spectroscopy.

Head and neck cancers are a significant global health burden, with radiation therapy being a frequently utilized treatment. The aim of this systematic review was to provide a critical appraisal of laboratory studies that assessed the effect of irradiation on the adhesive performance of resin-based biomaterials. The analysis included 23 laboratory studies obtained from five databases, with most studies using human enamel, dentin, or both, and bonding procedures involving the fabrication of direct restorations, standardized specimens, bonding of orthodontic brackets, and luting of endodontic fiber posts. The protocols used for irradiation varied, with most studies exposing specimens made from extracted teeth to irradiation using cabinet irradiators to simulate treatment of head and neck cancer. The findings indicate that irradiation reduces the bond strength of dental adhesives and resin-based composites on flat, ground enamel and dentin specimens, with different adhesives and timing of irradiation having a significant impact on adhesive performance. Irradiation also increased microleakage in most studies. The effect of irradiation on marginal adaptation of direct resin-based composite restorations was inconclusive. This systematic review indicates that irradiation has detrimental effects on the adhesive performance of resin-based biomaterials and highlights the need for further clinical and laboratory studies evaluating the performance of adhesive materials and approaches to improve it.

Onychomycosis is a common nail infection. Terbinafine-resistant dermatophyte infections pose an emerging global public health concern, but few cases have been described in the United States. We retrospectively reviewed and characterized clinical, histopathological, and mycological features of patients with mycologically confirmed onychomycosis who failed oral terbinafine treatment for onychomycosis at a U.S. academic nail referral center and ascertained for terbinafine-resistant isolates. During 1 June 2022–31 January 2023 at Weill Cornell Medicine in New York City, USA, 96 patients with mycologically confirmed onychomycosis were treated with oral terbinafine. Among 64 patients with adequate follow-up, 36 had clinical or complete cure. Of 28 patients who failed treatment, 17 underwent terbinafine resistance testing. Trichophyton rubrum with terbinafine resistance-conferring mutations was isolated from two patients. Overall, terbinafine failures for onychomycosis were relatively common, with some cases associated with terbinafine-resistant T. rubrum infections. These findings underscore the need for a clinical awareness of this emerging problem and public health efforts to monitor and prevent spread. We highlight the importance of diagnostic testing and species identification for onychomycosis patients and the increasingly important role of fungal identification and susceptibility testing to guide therapy.

Lichen planus is a chronic inflammatory disorder that may affect the skin, nails, and/or oral mucosa. Bullous lichen planus is a rare variant of lichen planus, which is even less common in the nails. We present a case of nail bullous lichen planus, in a 48-year-old male presenting with a 10-month history of onychodystrophy of all ten fingernails. A longitudinal excision of the left thumbnail was performed, with histopathology consistent with lichen planus with focal transition to bullous lichen planus. He was treated with intralesional triamcinolone injections to the fingernails monthly, with improvements noted after three treatments. Our patient’s nail bullous lichen planus manifested with longitudinal ridging, white-yellow discoloration, onycholysis, subungual hyperkeratosis, and v-shaped nicking. Histopathological findings included classical lichen planus changes, as well as formation of subepidermal bullae, colloid bodies, and extensive inflammatory infiltrate. Increased awareness and high index of suspicion for this condition are necessary, given the often late diagnosis reported in previously published cases.