494 research outputs found
Metal-bonded perovskite lead hydride with phonon-mediated superconductivity up to 46 K under atmospheric pressure
In the search for high-temperature superconductivity in hydrides, a plethora
of multi-hydrogen superconductors have been theoretically predicted, and some
have been synthesized experimentally under ultrahigh pressures of several
hundred GPa. However, the impracticality of these high-pressure methods has
been a persistent issue. In response, we propose a new approach to achieve
high-temperature superconductivity under atmospheric pressure by implanting
hydrogen into lead to create a stable few-hydrogen metal-bonded perovskite,
PbH. This approach diverges from the popular design methodology of
multi-hydrogen covalent high critical temperature () superconductors under
ultrahigh pressure. By solving the anisotropic Migdal-Eliashberg (ME)
equations, we demonstrate that perovskite PbH is a typical phonon-mediated
superconductor with a of 46 K, which is six times higher than that of
bulk Pb (7.22 K) and higher than that of MgB (39 K). The high can be
attributed to the strong electron-phonon coupling (EPC) strength of 2.45, which
arises from hydrogen implantation in lead that induces several high-frequency
optical phonon modes with a relatively large phonon linewidth resulting from H
atom vibration. The metallic-bonding in perovskite PbH not only improves
the structural stability but also guarantees better ductility than the widely
investigated multi-hydrogen, iron-based, and cuprate superconductors. These
results suggest that there is potential for the exploration of new
high-temperature superconductors under atmospheric pressure and may reignite
interest in their experimental synthesis soon.Comment: 6 pages, 4 figure
(E)-1-(2,4-Dihydroxyphenyl)-3-(4-hydroxyphenyl)prop-2-en-1-one monohydrate
In the title compound, C15H12O4·H2O, the two benzene rings are not coplanar, making a dihedral angle of 7.24 (16)°. An intramolecular hydroxy–carbonyl O—H⋯O hydrogen bond occurs. In the crystal, four intermolecular O—H⋯O hydrogen bonds involving the hydroxy residues, the carbonyl group and the water molecule lead to the formation of a three-dimensional network. The supramolecular structure is further stabilized by weak C—H⋯O interactions
Adverse events in the treatment of spinal muscular atrophy in children and adolescents with nusinersen: A systematic review and meta-analysis
ObjectivesTo systematically analyze adverse events (AEs) in treatment of spinal muscular atrophy (SMA) with Nusinersen in children and adolescents.MethodsThe study is registered on PROSPERO (CRD42022345589). Databases were searched and literature relating to Nusinersen in the treatment of spinal muscular atrophy in children from the start of database establishment to December 1, 2022, was retrospectively analyzed. R.3.6.3 statistical software was used, and random effects meta-analysis was performed to calculate weighted mean prevalence and 95% confidence intervals (CI).ResultsIn total, 15 eligible studies were included, with a total of 967 children. Rate of definite Nusinersen-related AEs was 0.57% (95% CI: 0%–3.97%), and probable Nusinersen-related AEs 7.76% (95% CI: 1.85%–17.22%). Overall rate of AEs was 83.51% (95% CI: 73.55%–93.46%), and serious AEs 33.04% (95% CI: 18.15%–49.91%). For main specific AEs, fever was most common, 40.07% (95% CI: 25.14%–56.02%), followed by upper respiratory tract infection 39.94% (95% CI: 29.43%–50.94%), and pneumonia 26.62% (95% CI: 17.99%–36.25%).The difference in overall AE rates between the two groups (Nusinersen group and placebo group) was significant (OR = 0.27,95% CI: 0.08–0.95, P = 0.042). Moreover, incidence of serious adverse events, and fatal adverse events were both significantly lower than in the placebo group (OR = 0.47, 95%CI: 0.32–0.69, P < 0.01), and (OR = 0.37, 95%CI: 0.23–0.59, P < 0.01), respectively.ConclusionNusinersen direct adverse events are rare, and it can effectively reduces common, serious, and fatal adverse events in children and adolescents with spinal muscular atrophy
Enhanced transdermal delivery of evodiamine and rutaecarpine using microemulsion
Yong-Tai Zhang, Ji-Hui Zhao, Su-Juan Zhang, Yang-Zi Zhong, Zhi Wang, Ying Liu, Feng Shi, Nian-Ping FengSchool of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, People&rsquo;s Republic of ChinaObjective: The purpose of this study was to improve skin permeation of evodiamine and rutaecarpine for transdermal delivery with microemulsion as vehicle and investigate real-time cutaneous absorption of the drugs via in vivo microdialysis.Methods: Pseudoternary phase diagrams were constructed to evaluate microemulsion regions with various surfactants and cosurfactants. Nine formulations of oil in water microemulsions were selected as vehicles for assessing skin permeation of evodiamine and rutaecarpine in ex vivo transdermal experiments. With a microdialysis hollow fiber membrane implanted in the skin beneath the site of topical drug administration, dialysis sampling was maintained for 10 hours and the samples were detected directly by high performance liquid chromatography. Real-time concentrations of the drugs in rat skin were investigated and compared with those of conventional formulations, such as ointment and tincture. Furthermore, the drugs were applied to various regions of the skin using microemulsion as vehicle.Results: In ex vivo transdermal experiments, cutaneous fluxes of evodiamine and rutaecarpine microemulsions were 2.55-fold to 11.36-fold and 1.17-fold to 6.33-fold higher, respectively, than those of aqueous suspensions. Different drug loadings, microemulsion water content, and transdermal enhancers markedly influenced the permeation of evodiamine and rutaecarpine. In microemulsion application with in vivo microdialysis, the maximum concentration of the drugs (evodiamine: 18.23 &plusmn; 1.54 ng/mL; rutaecarpine: 16.04 &plusmn; 0.69 ng/mL) were the highest, and the area under the curve0&ndash;t of evodiamine and rutaecarpine was 1.52-fold and 2.27-fold higher than ointment and 3.06-fold and 4.23-fold higher than tincture, respectively. A greater amount of drugs penetrated through and was absorbed by rat abdominal skin than shoulder and chest, and a reservoir in the skin was found to supply drugs even after the microemulsion was withdrawn.Conclusion: Compared to conventional formulations, higher cutaneous fluxes of evodiamine and rutaecarpine were achieved with microemulsion. Based on this novel transdermal delivery, the transdermal route was effective for the administration of the two active alkaloids.Keywords: microemulsion, evodiamine, rutaecarpine, transdermal delivery, microdialysi
Successful Use of a 5G-Based Robot-Assisted Remote Ultrasound System in a Care Center for Disabled Patients in Rural China
BackgroundDisability has become a global population health challenge. Due to difficulties in self-care or independent living, patients with disability mainly live in community-based care centers or institutions for long-term care. Nonetheless, these settings often lack basic medical resources, such as ultrasonography. Thus, remote ultrasonic robot technology for clinical applications across wide regions is imperative. To date, few experiences of remote diagnostic systems in rural care centers have been reported.ObjectiveTo assess the feasibility of a fifth-generation cellular technology (5G)-based robot-assisted remote ultrasound system in a care center for disabled patients in rural China.MethodsPatients underwent remote robot-assisted and bedside ultrasound examinations of the liver, gallbladder, spleen, and kidneys. We compared the diagnostic consistency and differences between the two modalities and evaluated the examination duration, image quality, and safety.ResultsForty-nine patients were included (21 men; mean age: 61.0 ± 19.0 [range: 19–91] years). Thirty-nine and ten had positive and negative results, respectively; 67 lesions were detected. Comparing the methods, 41 and 8 patients had consistent and inconsistent diagnoses, respectively. The McNemar and kappa values were 0.727 and 0.601, respectively. The mean duration of remote and bedside examinations was 12.2 ± 4.5 (range: 5–26) min and 7.5 ± 1.8 (range: 5–13) min (p < 0.001), respectively. The median image score for original images on the patient side and transmitted images on the doctor side was 5 points (interquartile range: [IQR]: 4.7–5.0) and 4.7 points (IQR: 4.5–5.0) (p = 0.176), respectively. No obvious complications from the examination were reported.ConclusionsA 5G-based robot-assisted remote ultrasound system is feasible and has comparable diagnostic efficiency to traditional bedside ultrasound. This system may provide a unique solution for basic ultrasound diagnostic services in primary healthcare settings
- …