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Solar energy utilization has gained considerable attention due to its abundance and renewability. However, its intermittent nature presents a challenge in harnessing its full potential. The development of energy storing compounds capable of capturing and releasing solar energy on demand has emerged as a potential solution. These compounds undergo a photochemical transformation that results in a high-energy metastable photoisomer, which stores solar energy in the form of chemical bonds and can release it as heat when required. Such systems are referred to as MOlecular Solar Thermal (MOST)-systems. Although the photoisomerization of MOST systems has been vastly studied, its back-conversion, particularly using heterogeneous catalysts, is still underexplored and the development of effective catalysts for releasing stored energy is crucial. Herein we compare the performance of 27 heterogeneous catalysts releasing the stored energy in an efficient Norbornadiene/Quadricyclane (NBD/QC) MOST system. We report the first benchmarking of heterogeneous catalysts for a MOST system using a robust comparison method of the catalysts' activity and monitoring the conversion using UV-Visible (UV-Vis) spectroscopy. Our findings provide insights into the development of effective catalysts for MOST systems. We anticipate that our assay will reveal the necessity of further investigation on heterogeneous catalysis.
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Mesenchymal tumors harboring GLI1 gene abnormalities are a rare but distinctive group of neoplasms whose clinicopathologic features are currently evolving. In particular, examples of this tumor with ACTB-GLI1 gene fusion, tentatively termed ACTB-GLI1 epithelioid mesenchymal neoplasm (EMN), show a distinctive monomorphic round-to-epithelioid morphology, nested to trabecular pattern of growth, and S100+/SOX10-/SMA- immunophenotype. We report the first case of this entity arising exclusively in the skin. A 69-year-old man with no prior history of neoplasia presented with a 1.5-cm raised lesion on the left buttock. Histopathologic examination revealed a diffuse dermal proliferation of small, monomorphic, round-to-ovoid cells with hyperchromatic nuclei, focally enlarged nucleoli, and minimal eosinophilic to clear-staining cytoplasm. These cells were arranged in confluent nests and trabeculae in a background of fibrocollagenous to focally myxoid stroma. Immunohistochemical analysis revealed strong positivity for S100 and CD56, and negativity for SOX-10, SMA, Melan-A, HMB-45, and a variety of other markers. Based on the morphology and immunophenotype, molecular studies were performed, which revealed the presence of an ACTB-GLI1 fusion transcript, confirming the diagnosis. Given the morphologic overlap of this tumor with other cutaneous round cell neoplasms and its potential for malignant behavior, ACTB-GLI1 EMN is an important entity for pathologists to recognize.
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Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Neoplasias de los Tejidos Blandos/genética , Neoplasias de los Tejidos Blandos/patología , Actinas/genética , Anciano , Células Epitelioides/patología , Fusión Génica , Humanos , Masculino , Proteína con Dedos de Zinc GLI1/genéticaRESUMEN
Isotopic response in dermatology refers to the development of a new primary dermatosis at the site of a previous reaction such as cutaneous herpes virus infection. We report a 63-year-old woman with a recent history of a bullous drug eruption treated with prednisone who presented with herpetic dermatitis and subsequent milia en plaque. This unique case represents a novel presentation of milia en plaque manifesting as a complication from post-herpetic isotopic response and highlights the wide array of isotopic responses that can occur following a cutaneous herpes simplex infection.
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Dermatitis , Quiste Epidérmico , Herpes Simple , Enfermedades de la Piel , Femenino , Humanos , Persona de Mediana Edad , Prednisona/uso terapéutico , Herpes Simple/complicaciones , Herpes Simple/diagnóstico , Herpes Simple/tratamiento farmacológicoRESUMEN
In this study, we investigate the effect of thermal treatment/calcination on the stability and activity of a Na-Mn-W/SiO2 catalyst for the oxidative coupling of methane. The catalyst performance and characterisation measurements suggest that the W species are directly involved in the catalyst active site responsible for CH4 conversion. Under operating conditions, the active components, present in the form of a Na-W-O-Mn molten state, are highly mobile and volatile. By varying the parameters of the calcination protocol, it was shown that these molten components can be partially stabilised, resulting in a catalyst with lower activity (due to loss of surface area) but higher stability even for long duration OCM reaction experiments.
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Addressing substance use disorders and social determinants of poor health at a population level is a major national healthcare priority. One promising model to improve healthcare outcomes for patients with these conditions is the Vulnerable Veteran Innovative Patient-Aligned Care Team (PACT) Initiative, or VIP - an interdisciplinary, team-based primary care delivery model designed to address the needs of vulnerable patients in the Veterans Health Administration. VIP establishes a single, integrated primary care environment for the management of substance use disorders, mental illness, social determinants of poor health, and complexities in care resulting from the co-occurrence of these conditions. We describe the origination, goals, and evolution of VIP to provide an example of how clinics and health systems can address vulnerable patient populations within a primary care clinic framework. While ongoing evaluation will be essential to understand its impact on patient outcomes and its sustainability and scalability in the future, VIP holds promise as a novel model to improve care for patients with addiction and other vulnerabilities.
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Grupo de Atención al Paciente/organización & administración , Atención Primaria de Salud/métodos , Trastornos Relacionados con Sustancias/terapia , Humanos , Evaluación de Programas y Proyectos de Salud , Estados Unidos , United States Department of Veterans Affairs , VeteranosRESUMEN
Conjugation of biomolecules for stable presentation is an essential step toward reliable chemically defined platforms for cell culture studies. In this work, we describe the formation of a stable and site-specific amide bond via the coupling of a cysteine terminated peptide at low concentration to an azlactone containing copolymer coating. A copolymer of polyethylene glycol methyl ether methacrylate-ran-vinyl azlactone-ran-glycidyl methacrylate P(PEGMEMA-r-VDM-r-GMA) was used to form a thin coating (20-30 nm) on silicon and polycarbonate substrates. The formation and stability of coating-peptide bonds for peptides containing free thiols and amines were quantified by X-ray photoelectron spectroscopy (XPS) after exposure to cell culture conditions. Peptides containing a thiol as the only nucleophile coupled via a thioester bond; however, the bond was labile under cell culture conditions and almost all the bound peptides were displaced from the surface over a period of 2 days. Coupling with N-terminal primary amine peptides resulted in the formation of an amide bond with low efficiency (<20%). In contrast, peptides containing an N-terminal cysteine, which contain both nucleophiles (free thiol and amine) in close proximity, bound with 67% efficiency under neutral pH, and were stable under the same conditions for 2 weeks. Control studies confirm that the stable amide formation was a result of an intramolecular rearrangement through a N-acyl intermediate that resembles native chemical ligation. Through a combination of XPS and cell culture studies, we show that the cysteine terminated peptides undergo a native chemical ligation process at low peptide concentration in aqueous media, short reaction time, and at room temperature resulting in the stable presentation of peptides beyond 2 weeks for cell culture studies.
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Materiales Biocompatibles Revestidos/síntesis química , Péptidos/química , Línea Celular , Materiales Biocompatibles Revestidos/farmacología , Cisteína/química , Humanos , Lactonas/química , Células Madre Mesenquimatosas/efectos de los fármacos , Cemento de Policarboxilato/química , Polietilenglicoles/síntesis química , Polietilenglicoles/farmacología , Ácidos Polimetacrílicos/síntesis química , Ácidos Polimetacrílicos/farmacología , Siliconas/químicaRESUMEN
BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is an uncommon, locally aggressive malignancy with wide local excision (WLE) or Mohs micrographic surgery (MMS) representing the treatment of choice. This article illustrates the experience of a single academic institution in treating DFSP with MMS and adds two particularly large, difficult closures of the glabella/central forehead and sternum to the body of literature. OBJECTIVE: To report the results of 15 patients with DFSP treated with MMS over a five-year period by a single Mohs surgeon at the University of Arkansas for Medical Sciences (UAMS). METHODS: A total of 15 patients between the ages of 16 and 80 years were diagnosed with DFSP and treated with MMS and were contacted in October 2021 to assess for recurrence. RESULTS: None of the 15 patients had a recurrence of DFSP following MMS, with a mean follow-up interval of 22.4 months and an average of 1.93 Mohs layers required for tumor clearance. CONCLUSION: This experience reaffirms that MMS is an effective treatment for DFSP and adds additional examples of closure techniques of large, ovoid surgical defects on the glabella/central forehead and sternum to the literature.
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BACKGROUND: To our knowledge, this is the first report to describe the histologic changes of a retinal astrocytic hamartoma (RAH) in a patient with tuberous sclerosis complex (TSC) treated with antivascular endothelial growth factor (anti-VEGF), as well as the longest anti-VEGF treatment that such a patient has received (3 years). Case Presentation. We present a case of a 20-year-old female with TSC who developed progressive growth of a papillary astrocytic hamartoma that caused significant retinal edema, vitreous hemorrhage, and neovascular glaucoma. The patient was initially treated with 25 intravitreal anti-VEGF injections about every 1-3 months, but eventually developed a blind painful eye from neovascular glaucoma. Histopathologic evaluation of the enucleated globe showed a peculiar difference of the tumor according to its topography, with features reminiscent of pilocytic astrocytoma at the optic nerve head and features reminiscent of subependymal giant cell astrocytoma at the retrolaminar optic nerve. We hypothesize that these changes occurred as a secondary effect of the anti-VEGF treatment. CONCLUSIONS: Anti-VEGF agents may decrease the ophthalmologic complications of RAH. We recommend that this treatment should be started early and continued for a protracted time at regular and frequent intervals. Moreover, a combination of therapies might prove to be superior to monotherapy and should therefore be considered in aggressive retinal astrocytic hamartomas.