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1.
Nat Commun ; 15(1): 5781, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987545

RESUMO

Controlling large-scale many-body quantum systems at the level of single photons and single atomic systems is a central goal in quantum information science and technology. Intensive research and development has propelled foundry-based silicon-on-insulator photonic integrated circuits to a leading platform for large-scale optical control with individual mode programmability. However, integrating atomic quantum systems with single-emitter tunability remains an open challenge. Here, we overcome this barrier through the hybrid integration of multiple InAs/InP microchiplets containing high-brightness infrared semiconductor quantum dot single photon emitters into advanced silicon-on-insulator photonic integrated circuits fabricated in a 300 mm foundry process. With this platform, we achieve single-photon emission via resonance fluorescence and scalable emission wavelength tunability. The combined control of photonic and quantum systems opens the door to programmable quantum information processors manufactured in leading semiconductor foundries.

2.
Dalton Trans ; 53(30): 12720-12739, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39017709

RESUMO

The synthesis of eleven new nickel Schiff base complexes each bearing four pendant groups is reported. The structures of the complexes differ in the identity of the pendant groups and/or diamine moiety. All complexes were characterised by microanalysis, Nuclear Magnetic Resonance (NMR) spectroscopy and Electrospray Ionisation Mass Spectrometry (ESI-MS), while the solid-state structures of two of the molecules were also determined using X-ray crystallographic methods. The DNA binding properties of the nickel complexes with double stranded DNA and a range of G-quadruplex DNA structures was explored using different spectroscopic methods as well as computational techniques. Results from ESI-MS experiments and Fluorescent Indicator Displacement (FID) assays were consistent with each other and indicated that varying the diamine moiety had less influence on DNA affinity than changing the pendant groups. These conclusions were also generally supported by results obtained from UV melting experiments and Fluorescence Resonance Energy Transfer (FRET) assays. The cytotoxicity of selected examples of the new complexes, and close analogues reported recently, towards V79 Chinese hamster lung cancer cells and THP-1 human leukemia cells was measured. All were found to display modest cytotoxicity, with flow cytometry experiments suggesting an apoptotic pathway was the most likely mechanism of cell death.


Assuntos
Complexos de Coordenação , Quadruplex G , Níquel , Bases de Schiff , Bases de Schiff/química , Níquel/química , Humanos , Animais , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , DNA/química , Cricetulus , Estrutura Molecular , Linhagem Celular Tumoral
4.
J Pediatr Pharmacol Ther ; 29(2): 151-158, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38596426

RESUMO

OBJECTIVE: An increase in maternal use of licit or illicit substances, alcohol, and tobacco has resulted in an increased incidence of neonatal abstinence syndrome (NAS). In recent years, NAS management has shifted to initiating an Eat, Sleep, Console (ESC) approach prior to pharmacologic treatment. The objective of this study was to evaluate the impact of ESC in combination with pharmacologic treatment in the management of NAS for infants exposed to substance use in utero. METHODS: This single system, multisite, retrospective cohort study evaluated infants with known exposure to substance or polysubstance use in utero or those who had signs and symptoms of withdrawal with a positive toxicology screen. The primary outcome of rate of pharmacologic therapy initiated was evaluated pre and post implementation of ESC. Secondary outcomes included hospital length of stay, day of life that pharmacologic therapy was initiated, and an evaluation of the ESC guideline. A subgroup analysis with similar outcomes was also performed for patients with maternal polysubstance use. RESULTS: A total of 2843 patients were screened, and 50 patients were randomly selected for -inclusion in both pre- and post-groups. The rate of pharmacologic therapy initiated post implementation of ESC decreased from 58% to 30% (p < 0.01). In the post-group, there was a decrease in the number of -patients requiring scheduled morphine (33%, p < 0.01) and duration of pharmacologic therapy (14.6 days vs 6.47 days, p < 0.01). CONCLUSIONS: Implementing an ESC guideline decreased the length of stay and rate of pharmacologic intervention needed for infants with NAS at our institution.

5.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38587447

RESUMO

A self-referenced interferometer to measure time-varying curvature in mechanically unstable environments is needed in many applications. One application that demands this measurement technique with fast data acquisition, 2D sensitivity, and insensitivity to vibration is the measurement of thermal strain in thin films in operational environments. The diverging beam interferometer described here demonstrates an angular sensitivity to the local curvature using interferograms captured by a CMOS camera. Two-dimensional Fourier analysis is used to extract curvature changes. The interferometer demonstrates an experimental sensitivity to curvature changes on the order of 10-4 m-1 and is used to measure thermal stresses in a cryogenic environment of a polycrystalline titanium nitride thin film on a silicon wafer that exhibits anisotropic curvature.

6.
JACC Case Rep ; 29(7): 102288, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38465285

RESUMO

A 54-year-old male with chronic pancreatitis presented with dyspnea. Computed tomography scans demonstrated a subdiaphragmatic fluid collection with pericardial fistulization. Pericardial fluid cultures were polymicrobial in nature. Purulent pericarditis is rare but carries a high mortality rate. We present the first documented case of pancreatico-pericardial fistulization causing purulent pericarditis.

7.
Emerg Med Pract ; 26(3): 1-24, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38393953

RESUMO

Each year, over 1.3 million patients visit the emergency department for constipation. Most cases are benign, but serious complications, such as fecal impaction and stercoral colitis, must be ruled out. Evidence to guide the evaluation and treatment of constipation in the emergency department is limited, and many of the decades-old treatments have not been studied in modern, rigorous, controlled trials. In the emergency department, constipation is a clinical diagnosis, and ideal management includes excluding dangerous mimics or complications and, for most patients, discharging the patient with a bowel regimen tailored to the likely cause of their constipation, with appropriate referral to primary or specialty care. This review evaluates consensus guidelines on management of constipation as well as the early data on the newer prescription medications for chronic and opioid-induced constipation.


Assuntos
Analgésicos Opioides , Constipação Intestinal , Humanos , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/diagnóstico , Constipação Intestinal/terapia , Analgésicos Opioides/uso terapêutico , Serviço Hospitalar de Emergência
8.
J Org Chem ; 89(3): 1836-1845, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38226655

RESUMO

A regioselective visible-light-mediated denitrogenative alkene insertion of 1,2,3-benzotriazin-4(3H)-ones was developed to access 3-substituted isoindolinones, an important structural motif present in many biologically active molecules and natural products. Notably, divergent reactivity was achieved by switching from reported nickel catalysis (where C3-substituted 3,4-dihydroisoquinolin-1(2H)-ones form) to photocatalysis, where photocatalytic denitrogenation and a subsequent nitrogen-mediated hydrogen atom shift lead to exclusive 3-substituted isoindolinone formation. The developed photocatalytic reaction is compatible with activated terminal alkenes and cyclic α,ß-unsaturated esters and ketones, with wide functional group tolerance for N-substitution of the 1,2,3-benzotriazin-4(3H)-ones. The utility of this procedure is highlighted by a gram-scale synthesis and postsynthetic amidation. To understand the origin of this unique product selectivity, experimental and computational mechanistic studies were performed.

9.
J Am Geriatr Soc ; 72(7): 2184-2194, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38259070

RESUMO

BACKGROUND: The EQUIPPED (Enhancing Quality of Prescribing Practices for Older Adults Discharged from the Emergency Department) medication safety program is an evidence-informed quality improvement initiative to reduce potentially inappropriate medications (PIMs) prescribed by Emergency Department (ED) providers to adults aged 65 and older at discharge. We aimed to scale-up this successful program using (1) a traditional implementation model at an ED with a novel electronic medical record and (2) a new hub-and-spoke implementation model at three new EDs within a health system that had previously implemented EQUIPPED (hub). We hypothesized that implementation speed would increase under the hub-and-spoke model without cost to PIM reduction or site engagement. METHODS: We evaluated the effect of the EQUIPPED program on PIMs for each ED, comparing their 12-month baseline to 12-month post-implementation period prescribing data, number of months to implement EQUIPPED, and facilitators and barriers to implementation. RESULTS: The proportion of PIMs at all four sites declined significantly from pre- to post-EQUIPPED: at traditional site 1 from 8.9% (8.1-9.6) to 3.6% (3.6-9.6) (p < 0.001); at spread site 1 from 12.2% (11.2-13.2) to 7.1% (6.1-8.1) (p < 0.001); at spread site 2 from 11.3% (10.1-12.6) to 7.9% (6.4-8.8) (p = 0.045); and at spread site 3 from 16.2% (14.9-17.4) to 11.7% (10.3-13.0) (p < 0.001). Time to implement was equivalent at all sites across both models. Interview data, reflecting a wide scope of responsibilities for the champion at the traditional site and a narrow scope at the spoke sites, indicated disproportionate barriers to engagement at the spoke sites. CONCLUSIONS: EQUIPPED was successfully implemented under both implementation models at four new sites during the COVID-19 pandemic, indicating the feasibility of adapting EQUIPPED to complex, real-world conditions. The hub-and-spoke model offers an effective way to scale-up EQUIPPED though a speed or quality advantage could not be shown.


Assuntos
Serviço Hospitalar de Emergência , Prescrição Inadequada , Melhoria de Qualidade , Humanos , Idoso , Serviço Hospitalar de Emergência/organização & administração , Prescrição Inadequada/prevenção & controle , Masculino , Lista de Medicamentos Potencialmente Inapropriados , Feminino , Registros Eletrônicos de Saúde , Alta do Paciente , COVID-19/epidemiologia , Segurança do Paciente
11.
J Biomol Struct Dyn ; : 1-15, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38115191

RESUMO

The omicron (B.1.19) variant of contagious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is considered a variant of concern (VOC) due to its increased transmissibility and highly infectious nature. The spike receptor-binding domain (RBD) is a hotspot of mutations and is regarded as a prominent target for screening drug candidates owing to its crucial role in viral entry and immune evasion. To date, no effective therapy or antivirals have been reported; therefore, there is an urgent need for rapid screening of antivirals. An extensive molecular modelling study has been performed with the primary goal to assess the inhibition potential of natural flavonoids as inhibitors against RBD from a manually curated library. Out of 40 natural flavonoids, five natural flavonoids, namely tomentin A (-8.7 kcal/mol), tomentin C (-8.6 kcal/mol), hyperoside (-8.4 kcal/mol), catechin gallate (-8.3 kcal/mol), and corylifol A (-8.2 kcal/mol), have been considered as the top-ranked compounds based on their binding affinity and molecular interaction profiling. The state-of-the-art molecular dynamics (MD) simulations of these top-ranked compounds in complex with RBD exhibited stable dynamics and structural compactness patterns on 200 nanoseconds. Additionally, complexes of these molecules demonstrated favorable free binding energies and affirmed the docking and simulation results. Moreover, the post-simulation validation of these interacted flavonoids using principal component analysis (PCA) revealed stable interaction patterns with RBD. The integrated results suggest that tomentin A, tomentin C, hyperoside, catechin gallate, and corylifol A might be effective against the emerging variants of SARS-CoV-2 and should be further evaluated using in-vitro and in-vivo experiments.Communicated by Ramaswamy H. Sarma.

12.
IDCases ; 34: e01922, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965382

RESUMO

Here, we present the case of a 55-year-old male with HIV and persistent lymphopenia who developed a paroxysmal severe cough for over three weeks. Microbiology studies were positive for abundant colonies of Bordetella bronchiseptica. He reports that his dog was also ill with a severe cough, suggesting a possible canine-to-human transmission. This zoonosis has been increasingly recognized and possesses significant morbidity and mortality, especially in immunocompromised hosts.

14.
Chemistry ; 29(69): e202302406, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37718289

RESUMO

A formal palladium-catalyzed decarboxylative (4+2) cycloaddition reaction between 4-vinylbenzoxazinanones and 2-nitro-1,3-enynes has been developed to produce highly valuable, densely functionalized tetrahydroquinolines in moderate to excellent yields with high diastereoselectivity under mild reaction conditions. The optimised protocol tolerates a range of substituted 2-nitro-1,3-enynes, which represent an under-utilized class of dipolarophile for transition-metal catalyzed cycloadditions. The employed reaction methodology facilitates efficient cycloaddition with both N-H- and N-Ts-4-vinylbenzoxazinanone dipole precursors. The stereochemistry of the major and minor diastereomeric (4+2) cycloadducts was determined by single crystal X-ray analyses. A mechanistic rationale for the high intrinsic diastereoselectivity and preliminary enantioselective experiments are also presented. The tetrahydroquinoline cycloadduct products feature numerous pendant functionalities, including a vinyl handle, an internal alkyne motif and a nitro functionality (which functions as a latent C-3 nitrogen substituent) for further synthetic manipulations.

15.
Dalton Trans ; 52(36): 12646-12660, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37622418

RESUMO

Three new nickel Schiff base complexes were prepared using a two-step procedure that involves initial selective dialkylation of 2,4,6-trihydroxybenzaldehyde, followed by reaction with 1,2-phenylenediamine and nickel(II) acetate. Each of the complexes possessed the same Schiff base core but differed in the identity of the four pendant groups. All complexes were characterised by microanalysis, NMR spectroscopy and ESI mass spectrometry. In addition, two of the complexes were also characterised in the solid state using X-ray crystallography, which confirmed the presence of a square planar geometry around the metal ion. The DNA binding properties of the three nickel complexes with double stranded DNA and a range of G-quadruplex DNA structures were explored using ESI mass spectrometry, CD spectroscopy, UV melting curves, Fluorescence Resonance Energy Transfer (FRET) assays, Fluorescent Indicator Displacement (FID) assays and molecular docking studies. These techniques confirmed the ability of the three nickel complexes to bind to most of the DNA molecules examined, as well as stabilise the latter in several instances. In addition, the results of these investigations provided evidence that pendant groups with morpholine rings generally reduced DNA binding behaviour, whilst pendants featuring piperidine ring systems attached to the Schiff base core by three and not two methylene linkers often showed the greatest extent of binding or DNA stabilisation.


Assuntos
Quadruplex G , Níquel , Simulação de Acoplamento Molecular , Bases de Schiff , Corantes
17.
J Periodontol ; 94(9): 1146-1149, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37470759
18.
Chemistry ; 29(53): e202301701, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37414734

RESUMO

The crotylation reactions of chiral α-F, α-OBz and α-OH aldehydes under Petasis-borono-Mannich conditions using (E)- or (Z)-crotylboronates and primary amines resulted in γ-addition products in high dr and high er. α-F and α-OBz aldehydes gave 1,2-anti-2,3-syn and 1,2-anti-2,3-anti, products, respectively while an α-OH aldehyde gave 1,2-syn-2,3-syn products. The stereochemical outcomes of reactions of the former aldehydes can be explained using a six-membered ring transition state (TS) model in which a Cornforth-like conformation around the imine intermediate is favoured resulting in 1,2-anti products. The 2,3-stereochemical outcome is dependent upon the geometry of the crotylboronate. These TS models were also supported by DFT calculations. The stereochemical outcomes of reactions employing an α-OH aldehyde can be rationalised as occurring via an open-TS involving H-bonding in the imine intermediate between the α-OH group and the imine N atom. Representative products were converted to highly functionalized 1,2,3,6-tetrahydropyridines and 3H-oxazolo[3,4-a]pyridine-3-ones which will be valuable scaffolds in synthesis.

20.
J Org Chem ; 88(13): 8738-8750, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37326851

RESUMO

Atropisomeric, bench-stable benzoazepine-fused isoindoles were synthesized via oxidation from isoindoline precursors. Using the isoindoles 5d-f as models, the stereochemistry and conformational folding of the systems were examined. Chiral UHPLC was used to analyze the rate of racemization and calculate the Gibbs free energy of enantiomerization (ΔG‡Enant). X-ray crystallography, 1H NMR spectroscopy, and DFT calculations were used to elucidate the three axes of chirality and clarify the structural factors contributing to ΔG‡Enant. Tandem rotation around the axes of chirality precludes the formation of diastereomers, with rotational restriction of the Caryl-Nsulfonamide bond determined as the moderator of atropisomeric stability in the system, affected primarily by steric hindrance as well as by π-stacking interactions facilitated by the folded conformation of the sulfonamide over the isoindole moiety.


Assuntos
Estereoisomerismo , Conformação Molecular , Cristalografia por Raios X , Teoria da Densidade Funcional , Espectroscopia de Ressonância Magnética
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