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1.
J Pediatr Orthop ; 44(3): 157-163, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-37994645

ABSTRACT

BACKGROUND: Cast immobilization is the mainstay of treatment for stable pediatric supracondylar humeral fractures (SCHFs). In recent years, a waterproof and breathable hybrid-mesh (HM) cast has emerged and been marketed to address common complaints such as itch, skin irritation, and malodor. Hence, this randomized controlled trial seeks to assess the overall satisfaction, comfort, and clinical outcomes of using HM casts in the conservative treatment of stable pediatric SCHF. METHODS: Seventy-nine patients (age range: 1 to 10 y) with modified Gartland's classification Type I and Type IIa SCHF were recruited and randomized for immobilization with either fiberglass or HM long-arm cast for 3 weeks. During follow-up visits, patients were assessed for any loss of reduction and skin rash. The weight of casts, the presence of cast breakage, the duration of cast application, and removal were recorded. A self-reported patient comfort and satisfaction questionnaire was also administered during the same visit. RESULTS: The final analysis included 38 patients immobilized with fiberglass casts and 39 patients with HM casts. Despite the significantly longer duration required for HM cast removal (4.18±1.25 min vs. 2.25±0.55 min, P <0.001), the HM cast was significantly lighter than its fiberglass counterpart (162.82±23.94 g vs. 203.95±36.52 g, P <0.001). The HM casts have better comfort (4.05±0.887 vs. 3.47±0.951, P =0.007) and satisfaction (3.69±1.055 vs. 3.11±0.953, P =0.012) scores as compared to fiberglass casts for immobilizing pediatric SCHF without compromising clinical outcome. CONCLUSIONS: HM casts have better comfort and overall satisfaction as compared to conventional fiberglass casts for immobilizing pediatric SCHF without compromising clinical outcomes. LEVEL OF EVIDENCE: Level II-therapeutic studies-investigating the results of treatment.


Subject(s)
Casts, Surgical , Humeral Fractures , Child , Child, Preschool , Humans , Infant , Conservative Treatment , Prostheses and Implants
2.
J Org Chem ; 88(1): 602-612, 2023 01 06.
Article in English | MEDLINE | ID: mdl-36524705

ABSTRACT

The site-selective incorporation of a trifluoromethyl group into biologically active molecules and pharmaceuticals has emerged as a central topic in medicinal chemistry and drug discovery. Herein, we demonstrate the rhodium(III)-catalyzed conjugate addition of ß-trifluoromethylated enones with quinoline N-oxides, which result in the generation of ß-trifluoromethyl-ß'-quinolinated ketones. The reaction proceeds under mild conditions with complete functional group tolerance. The synthetic applicability was showcased by successful gram-scale experiments and valuable synthetic transformations of coupling products.


Subject(s)
Quinolines , Rhodium , Oxides , Rhodium/chemistry , Catalysis , Ketones/chemistry
3.
J Org Chem ; 88(18): 13315-13326, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37668242

ABSTRACT

The site-selective modification of quinazolinone as a privileged bicyclic N-heterocycle is an attractive topic in medicinal chemistry and material science. We herein report the ruthenium(II)-catalyzed C-H allylation of 2-aryl quinazolinones with 2-methylidene cyclic carbonate. In addition, tandem C-H allylation and annulation are achieved under rhodium(III) catalysis, resulting in the formation of tetracyclic quinazolinones including a tertiary carbon center. Post-transformations of the synthesized products demonstrate the potential of the developed methodology. A series of mechanistic investigations were also performed.

4.
Phys Chem Chem Phys ; 25(16): 11756-11770, 2023 Apr 26.
Article in English | MEDLINE | ID: mdl-37067004

ABSTRACT

Herein we report the solution-combustion-method-synthesized Tb3+- and Tb3+/Yb3+-doped Gd3Ga5O12 nanophosphors, which possess luminescent and magnetic properties. The phase formation/crystal structure, and morphology of the prepared nanophosphors are studied using X-ray diffraction (XRD)/Raman spectroscopy and a field emission scanning electron microscope (FE-SEM), respectively. Tb3+/Yb3+-doped phosphor samples exhibit green emission with an intense band around 544 nm through downshifting (DS) and upconversion (UC) processes because of the 5D4 → 7F5 transition of Tb3+. In addition to this visible emission, these samples also show a NIR emission band around 1024 nm via the quantum cutting (QC) process due to the 2F5/2 → 2F7/2 transition of Yb3+. Emission decay measurements of the 5D4 → 7F5 transition of Tb3+ are performed to obtain the rate of energy transfer from Tb3+ to nearby Yb3+. Furthermore, using this energy transfer, the quantum cutting efficiencies were estimated. For their practical application, a selected sample was used to fabricate a LED device by combining the sample with a UV-C LED (274 nm). The obtained results, such as the activation energy (∼0.20 eV) and the high CRI value (78), suggest that the prepared sample can be utilized as a green-light-emitting agent in phosphor-coated (pc) WLEDs.

5.
Chemistry ; 28(51): e202200995, 2022 Sep 12.
Article in English | MEDLINE | ID: mdl-35697660

ABSTRACT

Tuberculosis (TB) is a leading source of infectious disease mortality globally. Antibiotic-resistant strains comprise an estimated 10 % of new TB cases and present an urgent need for novel therapeutics. ß-lactam antibiotics have traditionally been ineffective against M. tuberculosis (Mtb), the causative agent of TB, due to the organism's inherent expression of ß-lactamases that destroy the electrophilic ß-lactam warhead. We have developed novel ß-lactam conjugates, which exploit this inherent ß-lactamase activity to achieve selective release of pyrazinoic acid (POA), the active form of a first-line TB drug. These conjugates are selectively active against M. tuberculosis and related mycobacteria, and activity is retained or even potentiated in multiple resistant strains and models. Preliminary mechanistic investigations suggest that both the POA "warhead" as well as the ß-lactam "promoiety" contribute to the observed activity, demonstrating a codrug strategy with important implications for future TB therapy.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis , Antitubercular Agents/pharmacology , Antitubercular Agents/therapeutic use , Humans , Microbial Sensitivity Tests , Pyrazinamide/analogs & derivatives , Pyrazinamide/pharmacology , Tuberculosis/drug therapy , Tuberculosis/microbiology , beta-Lactams/pharmacology
6.
Langmuir ; 38(30): 9389-9399, 2022 Aug 02.
Article in English | MEDLINE | ID: mdl-35853215

ABSTRACT

Exploration of many strategies has continuously contributed to producing aggregation-induced red-emissive carbon dots (CDs). In this work, we designed fluorine-embedded (F-embedded) CDs from 1,2,4-triaminobenzene, thiourea, and ammonium fluoride (NH4F) exhibiting polymer-induced emission (PIE). The PIE phenomenon of fluorescent CDs is obtained in poly(vinyl alcohol) (PVA), showing emissions at 611 and 617 nm in the dispersed and solid states, respectively. The CDs exhibited a red shift of 28 nm in the PVA solution because PVA hydroxyl groups formed a robust bridge-like H-bonding network between CDs. The fluorine embedded in CDs enhanced the H-bond affinity toward PVA. It showed that this H-bond restricted the coupling of CDs' surface states and inhibited the nonirradiation transfer. For the solid state, surface PVA chains eliminated the π-π interaction of the conjugated core and constructed a self-quenching resistance polymeric system around CDs. As a result, CDs showed an unexpected red shift of fluorescence emission in PVA. Furthermore, white light-emitting diodes (WLEDs) have a correlated color temperature (CCT) of 5232 K, and a high color rendering index of 95 has been fabricated by integrating the red- and green-emissive films over the UV LEDs. Interestingly, the as-synthesized CDs showed room temperature phosphorescence (RTP), which enabled us to employ the CDs in double-security protection. Simultaneously, CDs have been used in fingerprint detection.

7.
J Urban Health ; 99(4): 749-759, 2022 08.
Article in English | MEDLINE | ID: mdl-35849318

ABSTRACT

In Indore, India, BHC engaged 247 multi-sector stakeholders through a systems mapping approach to gather qualitative data across three workshops and four citizen town halls from 2018 to 2020. These data were synthesized with results from BHC's 18 other city activities to build a systems map and identify high-impact areas for engagement. Contextual findings showed a tension at the heart of Indore's growth-Indore's great success as a city has spurred rapid population growth. This growth creates pressure on municipal systems as population outpaces service delivery capacity. This is central to the systems map that BHC developed and is expanded upon through additional patterns that fall within four main domains: (1) leadership, governance, and financing; (2) essential service delivery and workforce; (3) information systems; and (4) community infrastructure and education. Stakeholders found three key leverage opportunities within this context that, if included in every action, could help overcome barriers. These opportunities are: (1) improving data quality, use, and integration; (2) supporting accountability to, and enforcement of, policies and regulations; and (3) increasing community engagement. Brought together through a better understanding of the key patterns driving system behavior from the context map and leverage opportunities, BHC was able to co-create, with stakeholders, seven "coherent actions" to move Indore to a healthier, more equitable state. When COVID-19 regulations ease, BHC and city officials will reconvene to finalize an implementation plan for these actions.


Subject(s)
Health Status , Urban Health , COVID-19 , Cities , Humans , India , Leadership
8.
Phys Chem Chem Phys ; 24(46): 28584-28598, 2022 Nov 30.
Article in English | MEDLINE | ID: mdl-36412503

ABSTRACT

The as-prepared La1-xKxCoO3-δ (0 ≤ x ≤ 0.5) showed superior pseudocapacitive charge storage capacity in a neutral 0.5 M Na2SO4 electrolyte and superior electrocatalytic activities for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) in a 1 M KOH electrolyte. 30% K doped p-type La0.7K0.3CoO3-δ presents superior OER activity with an overpotential of ∼335 mV at 10 mA cm-2 current rate in a 1 M KOH electrolyte. Additionally, La1-xKxCoO3-δ (0 ≤ x ≤ 0.5) presents an excellent charge-storage capacitance in a neutral 0.5 M Na2SO4 electrolyte resulting in a gravimetric capacitance of the La0.5K0.5CoO3-δ electrode equivalent to 378 F g-1, 282 F g-1, 221 F g-1, 163 F g-1, and 74 F g-1 at a current density of 1 A g-1, 2 A g-1, 3 A g-1, 5 A g-1, and 10 A g-1, respectively. After 2500 continuous cycles of charge/discharge, the La0.5K0.5CoO3-δ//AC cell exhibits higher stability, capacitive retention (94%) and coulombic efficiency (97%). The gravimetric charge storage capacity of ASCs (La0.5K0.5CoO3-δ//AC) in the full cell mode showed capacitance equivalent to 308 F g-1, 287 F g-1, 238 F g-1, 209 F g-1 and 162 F g-1 at current densities of 1 A g-1, 2 A g-1, 3 A g-1, 5 A g-1 and 10 A g-1 in a neutral 0.5 M Na2SO4 electrolyte respectively. Maximum specific power equivalent to ∼6884 W kg-1 was observed at a current density of 10 A g-1 when the specific energy reached ∼57 W h kg-1 for the full cell. The double exchange mechanism coupled with stoichiometric oxygen defects present in the perovskite lattice seems to be operative behind the enhanced electrocatalytic OER properties, and additionally, it improves the charge storage kinetics of the La1-xKxCoO3-δ (0 ≤ x ≤ 0.5) electrode in a neutral Na2SO4 electrolyte for supercapacitor application. This work presents a rational strategy for introducing facile oxygen ion defects into perovskite structured La1-xKxCoO3-δ (0 ≤ x ≤ 0.5) to develop multifunctional electrode materials for a supercapacitor and energy conversion (OER/ORR) electrode of metal-air batteries.

9.
J Org Chem ; 86(17): 12247-12256, 2021 09 03.
Article in English | MEDLINE | ID: mdl-34406002

ABSTRACT

The direct functionalization of N-heterocycles is a vital transformation for the development of pharmaceuticals, functional materials, and other chemical entities. Herein, the transition-metal-free alkylation and acylation of C(sp2)-H bonds in biologically relevant 2-benzoxazinones with 1,4-dihydropyridines as readily accessible radical surrogates is described. Excellent functional group compatibility and a broad substrate scope were attained. Gram-scale reaction and transformations of the synthesized adducts via Suzuki coupling with heteroaryl boronic acids demonstrated the synthetic potential of the developed protocol.


Subject(s)
Dihydropyridines , Transition Elements , Acylation , Alkylation , Benzoxazines
10.
J Org Chem ; 86(11): 7579-7587, 2021 06 04.
Article in English | MEDLINE | ID: mdl-33949193

ABSTRACT

The site-selective modification of quinolines and their analogs has emerged as a pivotal topic in medicinal chemistry and drug discovery. Herein, we describe the rhodium(III)-catalyzed C8-alkylation of quinoline N-oxides with maleimides as alkylating agents, resulting in the formation of bioactive succinimide-containing quinoline derivatives. The reaction proceeds under mild conditions with complete functional group tolerance.


Subject(s)
Quinolines , Rhodium , Alkylation , Catalysis , Maleimides , Oxides
11.
J Org Chem ; 86(23): 16349-16360, 2021 12 03.
Article in English | MEDLINE | ID: mdl-34590482

ABSTRACT

The Rh(III)-catalyzed C-H functionalization and subsequent oxidative annulation between 5-aryl pyrazinones and internal alkynes are reported. This protocol provides facile access to a wide range of pyrazinone-linked naphthalenes via the C(sp2)-H alkenylation and subsequent annulation. This transformation is characterized by mild conditions, simplicity, and excellent functional group compatibility. Notably, it is a first report of the utilization of pyrazinones as directing groups in C-H functionalization.


Subject(s)
Alkynes , Rhodium , Catalysis , Oxidation-Reduction , Oxidative Stress
12.
Nanotechnology ; 32(15): 155504, 2021 Apr 09.
Article in English | MEDLINE | ID: mdl-33378748

ABSTRACT

A graphene/Si heterojunction device has been realized to overcome many different requests necessary to make it a versatile, widely used and competitive detector. The obtained photodetectors, which operate at room temperature, are sensitive in the spectral region from ultraviolet (240 nm) to infrared (2000 nm) and they can be used in different configurations that allow a high responsivity up to 107 A W-1, a rise time of a few nanoseconds, an external quantum efficiency greater than 300%, and a linear response for different light sources. This is allowed by the high quality of the graphene deposited on a large area of 8 mm2, and by the interdigitated design of the contacts, both preserving the excellent properties of graphene when switching from nanoscale to macroscopic dimensions of commonly used devices.

13.
Nano Lett ; 20(5): 3633-3641, 2020 05 13.
Article in English | MEDLINE | ID: mdl-32208704

ABSTRACT

Several works reported increased differentiation of neuronal cells grown on graphene; however, the molecular mechanism driving axon elongation on this material has remained elusive. Here, we study the axonal transport of nerve growth factor (NGF), the neurotrophin supporting development of peripheral neurons, as a key player in the time course of axonal elongation of dorsal root ganglion neurons on graphene. We find that graphene drastically reduces the number of retrogradely transported NGF vesicles in favor of a stalled population in the first 2 days of culture, in which the boost of axon elongation is observed. This correlates with a mutual charge redistribution, observed via Raman spectroscopy and electrophysiological recordings. Furthermore, ultrastructural analysis indicates a reduced microtubule distance and an elongated axonal topology. Thus, both electrophysiological and structural effects can account for graphene action on neuron development. Unraveling the molecular players underneath this interplay may open new avenues for axon regeneration applications.


Subject(s)
Axons , Endosomes , Graphite , Nerve Growth Factor/physiology , Animals , Cells, Cultured , Mice , Nerve Regeneration
14.
Angew Chem Int Ed Engl ; 60(1): 191-196, 2021 01 04.
Article in English | MEDLINE | ID: mdl-32930471

ABSTRACT

The direct methylation of N-heterocycles is an important transformation for the advancement of pharmaceuticals, agrochemicals, functional materials, and other chemical entities. Herein, the unprecedented C(sp2 )-H methylation of iminoamido heterocycles as nucleoside base analogues is described. Notably, trimethylsulfoxonium salt was employed as a methylating agent under aqueous conditions. A wide substrate scope and excellent level of functional-group tolerance were attained. Moreover, this method can be readily applied to the site-selective methylation of azauracil nucleosides. The feasibility of gram-scale reactions and various transformations of the products highlight the synthetic potential of the developed method. Combined deuterium-labeling experiments aided the elucidation of a plausible reaction mechanism.

15.
J Org Chem ; 85(4): 2476-2485, 2020 02 21.
Article in English | MEDLINE | ID: mdl-31904240

ABSTRACT

A transition-metal-free deoxygenative C-H amination reaction of azine-N-oxides with acyl azides is described. The initial formation of an isocyanate from the starting acyl azide via a Curtius rearrangement can trigger a [3 + 2] dipolar cycloaddition of polar N-oxide fragments to generate the aminated azine derivative. The applicability of this method is highlighted by the late-stage and sequential amination reactions of complex bioactive compounds, including quinidine and fasudil. Moreover, the direct transformation of aminated azines into various bioactive N-heterocycles illustrates the significance of this newly developed protocol.

16.
J Org Chem ; 85(11): 7014-7023, 2020 06 05.
Article in English | MEDLINE | ID: mdl-32275431

ABSTRACT

The preparation of phthalazinone derivatives is pivotal for their utilization as pharmaceutical agents and other entities. Herein, we report the phthalazinone-assisted carbon-nitrogen bond forming reaction using dioxazolones as robust amidation sources under Rh(III) catalysis. The broad functional group tolerance and complete site-selectivity are observed. Notably, a series of transformations of synthesized compounds into biologically relevant N-heterocycles demonstrates the applicability of the developed methodology.

17.
J Org Chem ; 85(4): 2520-2531, 2020 02 21.
Article in English | MEDLINE | ID: mdl-31904238

ABSTRACT

Ruthenium(II)-catalyzed C(sp2)-H functionalization of N-aryl phthalazinones with a range of aldehydes and activated ketone is described. Initial formation of hydroxyalkylated phthalazinones and subsequent Mitsunobu cyclization provided facile access to biologically relevant indazolophthalazinones. The utility of this method is highlighted by synthetic transformations into a series of potentially bioactive scaffolds.

18.
Org Biomol Chem ; 18(47): 9611-9622, 2020 12 21.
Article in English | MEDLINE | ID: mdl-33020797

ABSTRACT

The ruthenium(ii)-catalyzed cross-coupling reaction between 2-aryl quinazolinones and activated aldehydes is described. This method enables the site-selective hydroxyalkylation under redox-neutral conditions. Moreover, this protocol provides a facile access to various tetracyclic isoindoloquinazolinones by using Cu(OAc)2 as an external oxidant via C-H addition and subsequent intramolecular cyclization. A wide substrate scope and a high level of chemoselectivity as well as broad functional group tolerance are observed.

19.
J Microencapsul ; 37(5): 341-354, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32293928

ABSTRACT

Aim: The aim of this project is to improve the therapeutic effectiveness, permeation and retention of clobetasol propionate in sebaceous glands by reporting the use of Squarticles as lipidic nanosystem.Methods: Homogenisation method is used for the formulation of Squarticles (nanoemulgel) which was characterised on the basis of size, polydispersity index (PDI), viscosity, spreadability, DSC, % in vitro release, in vitro skin permeation deposition studies, and in vivo studies, scanning electron microscopic (SEM) and physical storage stability studies were done at different temperature conditions, i.e. 4 ± 2 °C, 25 ± 2 °C and 45 ± 2 °C for a period of 6 months for drug and formulation.Result: The morphological characterisation of prepared nanoemulsion shows small spherical shape and uniform size distribution as observed in the Scanning electron microscopic (SEM), having mean size (240.5 ± 9.2) and mean size distribution (0.282 ± 0.03) and zeta potential (-51.21). The drug release from optimised nanoemulsion (F2) in PBS (pH 5.5) was approximately 84.24 ± 1.35%, nanoemulgel formulations showed the release of 66.83 ± 2.05% while marketed gel showed the release of 57.67 ± 1.63% after 24 h. The cumulative percentage retention of clobetasol propionate loaded nanoemulgel was 63 ± 1.28% which was more than the marketed formulation (23.12% ±0.54). Physical stability studies show that formulation is more stable in cold condition. Further, the stability of active ingredient in gel formulation was determined using HPLC which shows around 15 ± 0.84% of loss in its activity.Conclusion: The present work has demonstrated the use of Squarticles as a novel carrier for treatment of plaque psoriasis by enhancing the better permeation, increasing skin retention, and enhances the effect of drug. The study also shows that the formulation is more stable in cold condition.


Subject(s)
Clobetasol/administration & dosage , Drug Carriers/chemistry , Drug Liberation , Nanoparticles/chemistry , Psoriasis/drug therapy , Skin/drug effects , Administration, Cutaneous , Animals , Disease Models, Animal , Female , Gels , Lipids/chemistry , Male , Microscopy, Electron, Scanning , Particle Size , Rats , Rats, Wistar , Rheology , Sebaceous Glands/drug effects , Skin Absorption , Temperature
20.
Small ; 15(50): e1904906, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31668009

ABSTRACT

The adoption of graphene in electronics, optoelectronics, and photonics is hindered by the difficulty in obtaining high-quality material on technologically relevant substrates, over wafer-scale sizes, and with metal contamination levels compatible with industrial requirements. To date, the direct growth of graphene on insulating substrates has proved to be challenging, usually requiring metal-catalysts or yielding defective graphene. In this work, a metal-free approach implemented in commercially available reactors to obtain high-quality monolayer graphene on c-plane sapphire substrates via chemical vapor deposition is demonstrated. Low energy electron diffraction, low energy electron microscopy, and scanning tunneling microscopy measurements identify the Al-rich reconstruction 31 × 31 R ± 9 ° of sapphire to be crucial for obtaining epitaxial graphene. Raman spectroscopy and electrical transport measurements reveal high-quality graphene with mobilities consistently above 2000 cm2 V-1 s-1 . The process is scaled up to 4 and 6 in. wafers sizes and metal contamination levels are retrieved to be within the limits for back-end-of-line integration. The growth process introduced here establishes a method for the synthesis of wafer-scale graphene films on a technologically viable basis.

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