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1.
J Am Chem Soc ; 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-39012041

ABSTRACT

Frustrated Lewis pairs (FLPs) offer an important and promising paradigm for main group catalysis. Reported here is the use of microwave dielectric spectroscopy for the in actu detection of FLP encounter complexes. This technique focuses on the room-temperature measurement of the loss component of microwave permittivity (ε2) over the bandwidth from 0.5 to 6.8 GHz. The microwave loss measured for a Lewis pair in a toluene host solution is compared with the losses of the individual components when measured separately, and the difference in loss Δε2 is used to characterize the electrostatic interaction between the pair. The Δε2 value shows a direct correlation with an ability for the FLP encounter complex to split hydrogen gas and abstract hydrogen from γ-terpinene and has led to the identification of a novel FLP encounter complex, tris-pentafluorophenyl borane-eucalyptol pairing.

2.
Public Health ; 231: 99-107, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38653017

ABSTRACT

OBJECTIVES: During the COVID-19 pandemic, public health measures were used to reduce the spread of COVID-19; it is unknown whether people with chronic conditions differentially adhered to public health measures. The objectives of this study were to evaluate the association between chronic conditions and adherence and to explore effect modification by sex, age, and income. STUDY DESIGN: An analysis of data from the Canadian Longitudinal Study on Aging COVID-19 Questionnaires (from April to September 2020) was conducted among middle-aged and older adults aged 50-96 years (n = 28,086). METHODS: Self-reported chronic conditions included lung disease, diabetes, heart disease, cancer, obesity, anxiety, and depression. Multinomial logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between chronic conditions and low, medium, and high levels of adherence. Effect modification was evaluated using statistical interaction and stratification. RESULTS: Most people (n = 17,435; 62%) had at least one chronic condition, and 2866 (10%) had three to seven chronic conditions. Among those with high adherence to public health measures, 69% had one or more chronic condition (n = 2266). Having three to seven chronic conditions, compared with none, was associated with higher adherence to public health measures (OR: 2.14; 95% CI: 1.12-1.42). Higher adherence was also noted across chronic conditions, for example, those with diabetes had higher adherence (OR: 1.72; 95% CI: 1.53-1.93). There was limited evidence of effect modification by sex, age, or income. CONCLUSIONS: Canadians with chronic conditions were more likely to adhere to public health measures; however, future research is needed to understand whether adherence helped to prevent adverse COVID-19 outcomes and if adherence had unintended consequences.


Subject(s)
COVID-19 , Self Report , Humans , COVID-19/epidemiology , COVID-19/prevention & control , Middle Aged , Male , Canada/epidemiology , Female , Aged , Longitudinal Studies , Chronic Disease/epidemiology , Aged, 80 and over , Public Health , SARS-CoV-2
3.
JACS Au ; 4(4): 1623-1631, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38665663

ABSTRACT

Reported here is the design and synthesis of a novel class of extended quinolizinium-fused corannulene derivatives with curved geometry. These intriguing molecules were synthesized through a rationally designed synthetic strategy, utilizing double Skraup-Doebner-Von Miller quinoline synthesis and a rhodium-catalyzed C-H activation/annulation (CHAA) as the key steps. Single-crystal X-ray analysis revealed a bowl depth of 1.28-1.50 Å and a unique "windmill-like" shape packing of 12a(2PF6-) due to the curvature and incorporation of two aminium ions. All of the newly reported curved salts exhibit green to orange fluorescence with enhanced quantum yields (Φf = 9-13%) and improved dispersibility compared to the pristine corannulene (Φf = 1%). The reduced optical energy gap and lower energy frontier orbital found by doping extended corannulene systems with nitrogen cations was investigated by UV-vis, fluorescence, and theoretical calculations. Electrochemical measurements reveal a greater electron-accepting behavior compared with that of their pyridine analogues. The successful synthesis, isolation, and evaluation of these curved salts provide a fresh perspective and opportunity for the design of cationic nitrogen-doped curved aromatic hydrocarbon-based materials.

4.
Am J Case Rep ; 25: e942418, 2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38366584

ABSTRACT

BACKGROUND The adenoids are lymphatic tissue located in the nasopharynx and play a role in upper-airway immunity. Inflammation of the adenoids is called adenoiditis, which can cause a variety of symptoms. This is a common condition and is due to acute viral or bacterial infection. Most patients experience mild symptoms of upper-respiratory tract infection with a self-limiting course. CASE REPORT A 5-year-old female patient was brought into the clinic by her parents with concerns regarding hearing and sleep. Clinical assessment was consistent with persistent otitis media with effusion and sleep-disordered breathing. She was scheduled for surgery, including nasendoscopy, adenoidectomy, and bilateral grommet insertion. During surgery, direct visualization of the postnasal space showed complete obstruction by hypertrophic, inflamed adenoids covered in a thick, white film. A biopsy was taken, which detected herpes virus cytopathic effect. A diagnostic workup excluded a neoplastic process and other bacterial or fungal infections. A trial of oral antiviral medication was successful and follow-up nasendoscopy showed resolution of adenoid hypertrophy. CONCLUSIONS Direct visualization of the postnasal space, with a transoral mirror or 120-degree endoscope, prior to adenoidectomy can aid diagnosis. Adenoiditis may be caused by a wide range of organisms, including herpes virus. Active mucopurulent discharge should raise concern for infection by bacteria, fungi, or virus. Previous research on viral infection of the adenoids have been in asymptomatic patients with presumed latent infection and undergoing elective adenoidectomy. To our knowledge, this is the first paper to report on successful treatment with antiviral medication alone.


Subject(s)
Adenoids , Otitis Media , Child, Preschool , Female , Humans , Adenoidectomy , Adenoids/microbiology , Adenoids/pathology , Adenoids/surgery , Antiviral Agents/therapeutic use , Hypertrophy , Nasopharynx/pathology
5.
Am J Respir Crit Care Med ; 209(2): 164-174, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-37938162

ABSTRACT

Rationale: Respiratory metagenomics (RMg) needs evaluation in a pilot service setting to determine utility and inform implementation into routine clinical practice. Objectives: Feasibility, performance, and clinical impacts on antimicrobial prescribing and infection control were recorded during a pilot RMg service. Methods: RMg was performed on 128 samples from 87 patients with suspected lower respiratory tract infection (LRTI) on two general and one specialist respiratory ICUs at Guy's and St Thomas' NHS Foundation Trust, London. Measurements and Main Results: During the first 15 weeks, RMg provided same-day results for 110 samples (86%), with a median turnaround time of 6.7 hours (interquartile range = 6.1-7.5 h). RMg was 93% sensitive and 81% specific for clinically relevant pathogens compared with routine testing. Forty-eight percent of RMg results informed antimicrobial prescribing changes (22% escalation; 26% deescalation) with escalation based on speciation in 20 out of 24 cases and detection of acquired-resistance genes in 4 out of 24 cases. Fastidious or unexpected organisms were reported in 21 samples, including anaerobes (n = 12), Mycobacterium tuberculosis, Tropheryma whipplei, cytomegalovirus, and Legionella pneumophila ST1326, which was subsequently isolated from the bedside water outlet. Application to consecutive severe community-acquired LRTI cases identified Staphylococcus aureus (two with SCCmec and three with luk F/S virulence determinants), Streptococcus pyogenes (emm1-M1uk clone), S. dysgalactiae subspecies equisimilis (STG62647A), and Aspergillus fumigatus with multiple treatments and public health impacts. Conclusions: This pilot study illustrates the potential of RMg testing to provide benefits for antimicrobial treatment, infection control, and public health when provided in a real-world critical care setting. Multicenter studies are now required to inform future translation into routine service.


Subject(s)
Anti-Infective Agents , Respiratory Tract Infections , Humans , Pilot Projects , London , Intensive Care Units , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/drug therapy
6.
J Cutan Pathol ; 51(1): 50-52, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37661598

ABSTRACT

Glomus tumors are well-known but relatively rare vascular neoplasms, with their malignant counterparts still being rarer. There are very few reports of cutaneous malignant glomus tumors, and the current limited evidence suggests that they follow a more indolent course than deep-seated malignant glomus tumors. Herein, we are reporting a case of cutaneous malignant glomus tumor. A 94-year-old male presented with a right-sided ulcerated scalp lesion, which, on biopsy, showed a diffusely infiltrative epithelioid malignancy with considerable pleomorphism and a notable perivascular growth pattern. The tumor cells were positive for smooth muscle actin (SMA) and h-caldesmon, and negative for cytokeratin MNF116, CK5, p40, S100, SOX10, HMB45, Melan-A, ERG, CD31, CD45, CD3, CD20, ALK, desmin, CD68, CD34, and HHV8. A diagnosis of cutaneous malignant glomus tumor was made, and the patient underwent a wider excision. Cutaneous malignant glomus tumors are extremely rare and should be considered when examining unusual cutaneous mesenchymal tumors.


Subject(s)
Glomus Tumor , Sarcoma , Skin Neoplasms , Male , Humans , Aged, 80 and over , Glomus Tumor/pathology , Skin Neoplasms/pathology , Antibodies, Monoclonal , Antigens, CD34
7.
Chimia (Aarau) ; 77(5): 339-345, 2023 May 31.
Article in English | MEDLINE | ID: mdl-38047830

ABSTRACT

The frustrations of precipitation, fouling and blockages of liquid-based flow reactors is familiar to all researchers that have worked with continuous flow equipment. There have been many innovative solutions to try and circumvent this issue. This short review will highlight the emerging technique of mechanochemistry and reactive extrusion as a continuous process that can directly work on solid (and liquid) materials and elicit chemical transformations.

8.
Proc Natl Acad Sci U S A ; 120(52): e2311995120, 2023 Dec 26.
Article in English | MEDLINE | ID: mdl-38113266

ABSTRACT

Neurons in the brain communicate with each other at their synapses. It has long been understood that this communication occurs through biochemical processes. Here, we reveal that mechanical tension in neurons is essential for communication. Using in vitro rat hippocampal neurons, we find that 1) neurons become tout/tensed after forming synapses resulting in a contractile neural network, and 2) without this contractility, neurons fail to fire. To measure time evolution of network contractility in 3D (not 2D) extracellular matrix, we developed an ultrasensitive force sensor with 1 nN resolution. We employed Multi-Electrode Array and iGluSnFR, a glutamate sensor, to quantify neuronal firing at the network and at the single synapse scale, respectively. When neuron contractility is relaxed, both techniques show significantly reduced firing. Firing resumes when contractility is restored. This finding highlights the essential contribution of neural contractility in fundamental brain functions and has implications for our understanding of neural physiology.


Subject(s)
Neurons , Synapses , Rats , Animals , Neurons/physiology , Synapses/physiology , Hippocampus , Neural Networks, Computer , Brain/physiology , Action Potentials/physiology , Models, Neurological
9.
Sci Rep ; 13(1): 17648, 2023 10 17.
Article in English | MEDLINE | ID: mdl-37848450

ABSTRACT

Congenital disorders of glycosylation (CDG) are rare genetic disorders with a spectrum of clinical manifestations caused by abnormal N-glycosylation of secreted and cell surface proteins. Over 130 genes are implicated and next generation sequencing further identifies potential disease drivers in affected individuals. However, functional testing of these variants is challenging, making it difficult to distinguish pathogenic from non-pathogenic events. Using proximity labelling, we identified OST48 as a protein that transiently interacts with lysyl oxidase (LOX), a secreted enzyme that cross-links the fibrous extracellular matrix. OST48 is a non-catalytic component of the oligosaccharyltransferase (OST) complex, which transfers glycans to substrate proteins. OST48 is encoded by DDOST, and 43 variants of DDOST are described in CDG patients, of which 34 are classified as variants of uncertain clinical significance (VUS). We developed an assay based on LOX N-glycosylation that confirmed two previously characterised DDOST variants as pathogenic. Notably, 39 of the 41 remaining variants did not have impaired activity, but we demonstrated that p.S243F and p.E286del were functionally impaired, consistent with a role in driving CDG in those patients. Thus, we describe a rapid assay for functional testing of clinically relevant CDG variants to complement genome sequencing and support clinical diagnosis of affected individuals.


Subject(s)
Congenital Disorders of Glycosylation , Humans , Glycosylation , Congenital Disorders of Glycosylation/diagnosis , Congenital Disorders of Glycosylation/genetics , Clinical Relevance , Base Sequence , Membrane Proteins/genetics , Membrane Proteins/metabolism
10.
Science ; 381(6655): 302-306, 2023 Jul 21.
Article in English | MEDLINE | ID: mdl-37471551

ABSTRACT

All fluorochemicals-including elemental fluorine and nucleophilic, electrophilic, and radical fluorinating reagents-are prepared from hydrogen fluoride (HF). This highly toxic and corrosive gas is produced by the reaction of acid-grade fluorspar (>97% CaF2) with sulfuric acid under harsh conditions. The use of fluorspar to produce fluorochemicals via a process that bypasses HF is highly desirable but remains an unsolved problem because of the prohibitive insolubility of CaF2. Inspired by calcium phosphate biomineralization, we herein disclose a protocol of treating acid-grade fluorspar with dipotassium hydrogen phosphate (K2HPO4) under mechanochemical conditions. The process affords a solid composed of crystalline K3(HPO4)F and K2-xCay(PO3F)a(PO4)b, which is found suitable for forging sulfur-fluorine and carbon-fluorine bonds.

12.
Disabil Rehabil ; : 1-9, 2023 May 15.
Article in English | MEDLINE | ID: mdl-37184357

ABSTRACT

PURPOSE: Physical activity (PA) is proposed for long-term problems after traumatic brain injury (TBI) with mood, quality of life, and participation. However, COVID-19 mitigation strategies resulted in widespread closures of community-based fitness centres, including one housing a peer-assisted PA program (TBI-Health). The purpose of this study was to provide an in-depth exploration of COVID-19's impact on the TBI-Health program for adults with moderate-to-severe TBI and determine how their PA behaviours could be supported in the pandemic. METHODS: Interpretative phenomenological analysis was employed to collect and analyze data from semi-structured Zoom-facilitated interviews with seven female and nine male adults with moderate-to-severe TBI (including program participants and mentors). RESULTS: Three major themes were identified. Need for PA after TBI included specific benefits of PA after TBI and desire for an adapted PA program. Lasting Impacts of the TBI-Health Program identified belonging to the TBI-Health community, benefits, and knowledge transfer from the program. Resilience and Loss through the Pandemic comprised the repercussions of COVID-19, loss of the PA program, adapting PA to the pandemic, and resilience after TBI. CONCLUSION: This study provides insights about impacts of participating in community-based peer-assisted PA programs after moderate-to-severe TBI and ways to support PA in unforeseen circumstances.IMPLICATIONS FOR REHABILITATIONOur community-based peer-assisted physical activity program for adults with moderate-to-severe traumatic brain injury (TBI) promoted a range of daily and social activities.Outdoor group-based physical activity programs provide physical activity and social opportunities for adults with moderate-to-severe TBI when indoor physical activity is restricted.Community-based peer-assisted physical activity programs can assist with posttraumatic growth after moderate-to-severe TBI.

13.
Brain Inj ; 37(8): 728-736, 2023 07 03.
Article in English | MEDLINE | ID: mdl-37157834

ABSTRACT

PRIMARY OBJECTIVE: To explore the experiences of program mentors, participants, and employees involved in a peer-based physical activity (PA) program for adults with moderate-to-severe TBI, being piloted by a community fitness center, to develop the program as a measurable intervention. RESEARCH DESIGN: We adopted an exploratory case study approach through an interpretivist paradigm, which focused on discovering realities about the peer-based PA program across the study participants' views, backgrounds, and experiences. METHODS AND PROCEDURES: Semi-structured focus groups and individual interviews were conducted with nine adult program participants (3 peer mentors, 6 participants), and three program employees. Inductive content analysis was used to develop themes about their perceived experiences. MAIN OUTCOMES AND RESULTS: 44 open-codes were grouped into 10 subthemes and three final themes: 1) program impacts identified the importance of the program in daily life and resulting psychological, physical, and social outcomes; 2) program characteristics highlighted program leaders, accessibility, and social inclusion; 3) program sustainability included program adherence, benefits for the center, and the program's future. CONCLUSIONS: Perceptions of program experiences and outcomes identified how peer-based PA for adults with moderate-to-severe TBI can lead to meaningful activities, functioning better, and buy-in from all parties. Implications for research and practice related to supporting health-related behaviors after TBI through group-based, autonomy-supporting approaches are discussed.


Subject(s)
Brain Injuries, Traumatic , Exercise , Humans , Adult , Mentors/psychology , Peer Group
14.
Proc Biol Sci ; 290(1991): 20221496, 2023 01 25.
Article in English | MEDLINE | ID: mdl-36651050

ABSTRACT

Attentional set shifting is a core ingredient of cognition, allowing for fast adaptation to changes in the environment. How this skill compares between humans and other primates is not well known. We examined performance of 3- to 5-year-old children and chimpanzees on a new attentional set shifting task. We presented participants with two shelves holding the same set of four boxes. To choose the correct box on each shelf, one has to switch attention depending on which shelf one is currently presented with. Experiment 1 (forty-six 3- to 5-year olds, predominantly European White) established content validity, showing that the majority of errors were specific switching mistakes indicating failure to shift attention. Experiment 2 (one hundred and seventy-eight 3- to 6-year olds, predominantly European White) showed that older children made fewer mistakes, but if mistakes were made, a larger proportion were switching mistakes rather than 'random' errors. Experiment 3 (52 chimpanzees) established suitability of the task for non-human great apes and showed that chimpanzees' performance was comparable to the performance of 3- and 4-year olds, but worse than 5-year olds. These results suggest that chimpanzees and young children share attentional set shifting capacities, but that there are unique changes in the human lineage from 5 years of age.


Subject(s)
Attention , Pan troglodytes , Animals , Humans , Child, Preschool , Child , Adolescent , Cognition , Reversal Learning
15.
Ann R Coll Surg Engl ; 105(3): 196-202, 2023 Mar.
Article in English | MEDLINE | ID: mdl-35617051

ABSTRACT

INTRODUCTION: Isolated volar dislocations of the distal radioulnar joint are reported as rare. We observed three such cases over a 12-month period. Literature to date consists of multiple case reports and case series with no structured reviews. There is debate as to incidence, mechanism, investigation, treatment and prognosis. METHODS: A case series and formal systematic review was performed. This included an analysis of the demographics, mechanism, presentation, investigation, treatment and outcome of the cases identified from the wider published series. FINDINGS: In total 99 cases of this injury were identified from 59 papers, with a further 9 cases having an associated ulna styloid fracture. CONCLUSIONS: This is a rare injury, representing up to 0.02% of all bony injuries, which is diagnosed late in 36% of cases. Inability to obtain a true lateral radiograph may contribute to the diagnosis being missed. Computed tomography scans are useful in suspected cases without radiographic confirmation. Acute cases are successfully treated with closed reduction in 78% of cases; however associated soft tissue injuries may need to be surgically addressed. Delayed presentation is more likely to require open surgery and preoperative MRI scans are indicated to aid surgical planning. Chronic instability rarely occurs and may need treatment with reconstruction or salvage. A good, subjective, result is reported in the majority of patients.


Subject(s)
Joint Dislocations , Radius Fractures , Ulna Fractures , Wrist Injuries , Humans , Wrist Injuries/diagnostic imaging , Wrist Injuries/surgery , Joint Dislocations/diagnostic imaging , Joint Dislocations/surgery , Wrist Joint/diagnostic imaging , Wrist Joint/surgery , Ulna Fractures/diagnostic imaging , Ulna Fractures/surgery , Radiography , Radius Fractures/diagnostic imaging , Radius Fractures/surgery
16.
Neurorehabil Neural Repair ; 37(6): 367-373, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36226541

ABSTRACT

BACKGROUND: Vagus Nerve Stimulation (VNS) paired with rehabilitation improved upper extremity impairment and function in a recent pivotal, randomized, triple-blind, sham-controlled trial in people with chronic arm weakness after stroke. OBJECTIVE: We aimed to determine whether treatment effects varied across candidate subgroups, such as younger age or less injury. METHODS: Participants were randomized to receive rehabilitation paired with active VNS or rehabilitation paired with sham stimulation (Control). The primary outcome was the change in impairment measured by the Fugl-Meyer Assessment Upper Extremity (FMA-UE) score on the first day after completion of 6-weeks in-clinic therapy. We explored the effect of VNS treatment by sex, age (≥62 years), time from stroke (>2 years), severity (baseline FMA-UE score >34), paretic side of body, country of enrollment (USA vs UK) and presence of cortical involvement of the index infarction. We assessed whether there was any interaction with treatment. FINDINGS: The primary outcome increased by 5.0 points (SD 4.4) in the VNS group and by 2.4 points (SD 3.8) in the Control group (P = .001, between group difference 2.6, 95% CI 1.03-4.2). The between group difference was similar across all subgroups and there were no significant treatment interactions. There was no important difference in rates of adverse events across subgroups. CONCLUSION: The response was similar across subgroups examined. The findings suggest that the effects of paired VNS observed in the VNS-REHAB trial are likely to be consistent in wide range of stroke survivors with moderate to severe upper extremity impairment.


Subject(s)
Ischemic Stroke , Motor Disorders , Stroke Rehabilitation , Stroke , Vagus Nerve Stimulation , Humans , Middle Aged , Motor Disorders/etiology , Stroke/complications , Stroke/therapy , Upper Extremity , Recovery of Function , Treatment Outcome
19.
ACS Catal ; 12(21): 13681-13689, 2022 Nov 04.
Article in English | MEDLINE | ID: mdl-36366760

ABSTRACT

The cross-electrophile coupling of either twisted-amides or heteroaryl halides with alkyl halides, enabled by ball-milling, is herein described. The operationally simple nickel-catalyzed process has no requirement for inert atmosphere or dry solvents and delivers the corresponding acylated or heteroarylated products across a broad range of substrates. Key to negating the necessity of inert reaction conditions is the mechanical activation of the raw metal terminal reductant: manganese in the case of twisted amides and zinc for heteroaryl halides.

20.
Appl Opt ; 61(16): 4927-4931, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-36255978

ABSTRACT

A 2×2 photonic coupler is realized at the intersection of two 480nm×220nm silicon on insulator waveguides. The designed 2×2 coupler is simulated in both High Frequency Simulator System (HFSS) and Lumerical and shows an equal split of an input signal into transmitted and reflected signals for a 45 deg, ∼100nmSiO2 filled trench. The principle of operation of the coupler is frustrated total internal reflection. Thus, this behavior is reasonably flat across wavelength, which is confirmed by Lumerical simulations and by experiment. Also, it has been shown that this coupler has a flat behavior across trench thickness for the chosen geometry and material system, which makes it insensitive to fabrication variation and resolution. We are interested to make this coupler a part of silicon photonic foundry process development kits. Therefore, fabrication is done at the AIM Photonics Foundry to study the performance in the context of the foundry's design rules and process flow of the foundry. Good agreement between theory and experiment is reported herein. A 2×2 trench coupler is, when operated in the single photon or quantum regime, an integrated photonic realization of a Hadamard gate.

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