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1.
Eur Stroke J ; 8(2): 423-433, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37231691

RESUMO

PURPOSE: Perihaematomal oedema (PHO) formation has gained increasing interest as a therapeutic target after spontaneous intracerebral haemorrhage (ICH). Whether PHO contributes to poor outcome is unclear. We aimed to determine the association between PHO and outcome in patients with spontaneous ICH. METHOD: We searched five databases up to 17 November 2021 for studies of ⩾10 adults with ICH reporting the presence of PHO and outcome. We assessed risk of bias, extracted aggregate data and used random effects meta-analysis to pool studies that reported odds ratios (OR) with 95% confidence intervals (CI). Primary outcome was poor functional outcome defined as modified Rankin Scale score of 3-6 at 3 months. Additionally, we assessed PHO growth and poor outcome at any time of follow-up. We prospectively registered the protocol in PROSPERO (CRD42020157088). FINDINGS: We identified 12,968 articles, of which we included 27 studies (n = 9534). Eighteen studies reported an association between larger PHO volume and poor outcome, six a neutral result and three an inverse relationship. Larger absolute PHO volume was associated with poor functional outcome at 3 months (OR per mL increase of absolute PHO 1.03, 95% CI 1.00-1.06, I2 44%, four studies). Additionally, PHO growth was associated with poor outcome (OR 1.04, 95% CI 1.02-1.06, I2 0%, seven studies). DISCUSSION: In patients with spontaneous ICH, larger PHO volume is associated with poor functional outcome at 3 months. These findings support the development and investigation of new therapeutic interventions targeting PHO formation to evaluate if reduction of PHO improves outcome after ICH.


Assuntos
Edema Encefálico , Hemorragia Cerebral , Adulto , Humanos , Hemorragia Cerebral/terapia , Edema , Edema Encefálico/etiologia
2.
Chemistry ; 29(6): e202203006, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36322831

RESUMO

Diol scaffolds have been utilized as highly effective catalysts and ligands in a wide range of catalytic asymmetric transformations. For scaffolds to be successful as broadly used motifs, they should be prepared cheaply through facile routes and be easily handled. Herein, the synthesis of a family of planar chiral diols based on a modular and robust three-step route is described, which yields catalytically active diols in >99 % de and >99 % ee, with up to seven different chiral elements. These diols have been characterized by X-ray crystallographic analysis, which provides clear evidence for the likely transition state when applied in the asymmetric hetero-Diels-Alder reaction. Without altering the stereochemistry of the catalyst backbone, it is possible to access both enantiomers of the product by varying the substitution of the catalyst at the α-position.

3.
Phys Sportsmed ; 51(4): 306-312, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-35459426

RESUMO

OBJECTIVE: Little information exists about horse-related injury admissions to Level 1 trauma centers in the Western United States. This study describes injury patterns in this population, to reveal potential areas for injury prevention initiatives. METHODS: A retrospective database review of 512 non-fatal equine-related injuries over a 15-year period was conducted, using a Level 1 hospital trauma registry. To determine patterns of injury, patients injured by riding or being near a horse were classified according to age, sex, helmet use, abbreviated injury score, anatomical region injured, and length of stay. RESULTS: Equine-related injury was more frequent among females than males, the anatomical region most at risk among adults was the lower extremity (including pelvis), and among children and youth, the head. 75% of head-injured patients were not wearing a helmet at the time of injury and those with the most severe head injuries were least likely to be wearing a helmet. CONCLUSION: Preventable equine-related injuries occur across all ages, are more frequent among females, and affect all regions of the body. Despite head-injury risks associated with horse activities, helmet use was not common among most of the injured. Decreasing the risk of these injuries requires use of appropriate protective equipment and enhanced education campaigns aimed at those in the horse industry and the general public.


Assuntos
Traumatismos Craniocerebrais , Centros de Traumatologia , Masculino , Feminino , Cavalos , Humanos , Animais , Estados Unidos , Estudos Retrospectivos , Escala de Gravidade do Ferimento , Hospitalização , Traumatismos Craniocerebrais/epidemiologia , Dispositivos de Proteção da Cabeça , Hospitais
4.
Org Lett ; 24(48): 8886-8889, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36446080

RESUMO

We report a general, catalyst-controlled route to prostaglandin F2α and its analogues. The approach uses a Rh-catalyzed dynamic kinetic asymmetric Suzuki-Miyaura coupling reaction between a racemic bicyclic allyl chloride and alkenyl boronic esters bearing chiral alcohols to give cyclopentyl intermediates bearing 3 contiguous stereocenters. The route provides advanced intermediates in 99% ee as a single diastereoisomer in all cases examined, with the absolute stereochemistry of the cyclopentane core controlled by the ligand. Intermediates that could be used to produce prostaglandin analogues such as bimatoprost, latanoprost, fluprostenol, and cloprostenol were synthesized. The final two stereocenters were installed via Pd-catalyzed Tsuji-Trost alkylation and iodolactonization. The synthesis of PG F2α was achieved in 19% yield in 16 longest linear steps.


Assuntos
Dinoprosta , Dinoprosta/análogos & derivados , Dinoprosta/síntese química , Catálise
5.
Org Process Res Dev ; 26(11): 3153-3160, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36437898

RESUMO

Csp2-Csp2 Suzuki-Miyaura couplings (SMCs) are ubiquitous in the synthesis of small molecules, but analogous Csp2-Csp3 bond-forming SMCs are rare, especially asymmetric variants. Recently, we developed a series of Rh-catalyzed couplings between racemic sp3-hybridized allyl chlorides and heteroaryl boronic acids. Here, we demonstrate that these catalytic asymmetric reactions can be scaled-up to give over 100 g of a product. The reaction we chose to test couples a heteroaromatic boronic acid derivative and a racemic bicyclic electrophile to give a product with three contiguous stereogenic centers. The SMC product was obtained as a single diastereomer in 90% yield and 98% ee. Kinetic analysis of the reaction reveals two exothermic steps in the reaction setup and revealed the means by which to prevent the generation of heat spikes detrimental to the stability of the catalyst.

6.
Int J Stroke ; 16(7): 828-839, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34165016

RESUMO

BACKGROUND: Hospital-based studies have reported variable associations between outcome after spontaneous intracerebral hemorrhage and peri-hematomal edema volume. AIMS: In a community-based study, we aimed to investigate the existence, strength, direction, and independence of associations between intracerebral hemorrhage and peri-hematomal edema volumes on diagnostic brain CT and one-year functional outcome and long-term survival. METHODS: We identified all adults, resident in Lothian, diagnosed with first-ever, symptomatic spontaneous intracerebral hemorrhage between June 2010 and May 2013 in a community-based, prospective inception cohort study. We defined regions of interest manually and used a semi-automated approach to measure intracerebral hemorrhage volume, peri-hematomal edema volume, and the sum of these measurements (total lesion volume) on first diagnostic brain CT performed at ≤3 days after symptom onset. The primary outcome was death or dependence (scores 3-6 on the modified Rankin Scale) at one-year after intracerebral hemorrhage. RESULTS: Two hundred ninety-two (85%) of 342 patients (median age 77.5 y, IQR 68-83, 186 (54%) female, median time from onset to CT 6.5 h (IQR 2.9-21.7)) were dead or dependent one year after intracerebral hemorrhage. Peri-hematomal edema and intracerebral hemorrhage volumes were colinear (R2 = 0.77). In models using both intracerebral hemorrhage and peri-hematomal edema, 10 mL increments in intracerebral hemorrhage (adjusted odds ratio (aOR) 1.72 (95% CI 1.08-2.87); p = 0.029) but not peri-hematomal edema volume (aOR 0.92 (0.63-1.45); p = 0.69) were independently associated with one-year death or dependence. 10 mL increments in total lesion volume were independently associated with one-year death or dependence (aOR 1.24 (1.11-1.42); p = 0.0004). CONCLUSION: Total volume of intracerebral hemorrhage and peri-hematomal edema, and intracerebral hemorrhage volume alone on diagnostic brain CT, undertaken at three days or sooner, are independently associated with death or dependence one-year after intracerebral hemorrhage, but peri-hematomal edema volume is not. DATA ACCESS STATEMENT: Anonymized summary data may be requested from the corresponding author.


Assuntos
Edema Encefálico , Acidente Vascular Cerebral , Adulto , Humanos , Feminino , Idoso , Masculino , Estudos Prospectivos , Edema Encefálico/diagnóstico por imagem , Edema Encefálico/etiologia , Estudos de Coortes , Acidente Vascular Cerebral/complicações , Hemorragia Cerebral/complicações , Hemorragia Cerebral/diagnóstico por imagem , Hematoma/diagnóstico por imagem , Hematoma/complicações
7.
Org Biomol Chem ; 18(46): 9538, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33231583

RESUMO

Correction for 'Recent developments in the synthesis and applications of chiral ferrocene ligands and organocatalysts in asymmetric catalysis' by Laura Cunningham et al., Org. Biomol. Chem., 2020, DOI: 10.1039/d0ob01933j.

8.
Org Biomol Chem ; 18(46): 9329-9370, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33155613

RESUMO

With the ever-present need for novel asymmetric methodologies in organic synthesis to allow chemists to access enantiopure compounds, so too is there a need for new chiral ligands and organocatalysts to affect these transformations. Due to the unique properties of ferrocene and its derivatives, ferrocenyl compounds are unsurprisingly considered privileged structures in asymmetric catalysis. The versatility of the ferrocene moiety gives rise to a vast range of diverse ligand and catalyst motifs which are successful in broad ranges of mechanistically distinct reactions. This review details recent advances in the application of ferrocenyl mono-, bi- and tridentate-ligands and ferrocene-derived organocatalysts in asymmetric catalysis. Given the necessity for the development of new approaches to expand the scope of ferrocenyl ligands and catalysts, this review also illustrates the development of elegant and novel methodologies for the synthesis of ferrocenyl compounds.

9.
Chembiochem ; 21(20): 2974-2981, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32453493

RESUMO

The design and first enantioselective synthesis of a series of chiral ferrocifens and ferrociphenols was realised by enantioselective palladium-catalysed intramolecular direct C-H bond activation followed by McMurry coupling. Biological evaluation revealed moderate anticancer activities on breast cancer cells and evidence of chiral discrimination between enantiomers. Treatment of the novel ferrocifens with Ag2 O revealed that these systems are unable to form a neutral quinone methide, yet still demonstrate marked antiproliferative properties against both the hormone-dependent MCF-7 and hormone-independent MDA-MB-231 cell lines. This bioactivity arises from two mechanisms: Fenton-type chemistry and the anti-estrogenic activity associated with the tamoxifen-like structure.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Compostos Ferrosos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias da Mama/patologia , Catálise , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Compostos Ferrosos/síntese química , Compostos Ferrosos/química , Humanos , Estrutura Molecular , Paládio/química , Estereoisomerismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
11.
Artigo em Inglês | MEDLINE | ID: mdl-30889975

RESUMO

Objectives: Launched in 1989, the Scottish Motor Neuron Disease Register (SMNDR) has provided a resource for prospective clinical data collection. However, in 2015 we aimed to evolve a system to allow: i) A patient-centered approach to care based on recognized standards, ii) Harmonized data sharing between Scottish health professionals in "real-time", iii) Regular audit of care to facilitate timely improvements in service delivery, and iv) Patient participation in a diverse range of observational and interventional research studies including clinical trials. Methods: We developed a standardized national electronic data platform-Clinical Audit Research and Evaluation of MND (CARE-MND) which integrates clinical audit and research data fields. Data completion pre- and post-CARE-MND were compared, guided by recently published National Institute for Clinical Excellence (NICE) recommendations. Statistical difference in data capture between time periods was assessed using Z-test of proportions. Results: Data field completion for the historical 2011-2014 period ranged from 4 to 95%; median 50%. CARE-MND capture ranged from 32 to 98%; median 87%. 15/17 fields were significantly more complete post-CARE-MND (p < 0.001). All MND nurse/allied health specialists in Scotland use the CARE-MND platform. Management of MND in Scotland is now coordinated through a standardized template. Conclusions: Through CARE-MND, national audits of MND care and interventions have been possible, leading to protocols for harmonized service provision. Stratification of the MND population is facilitating participation in observational and interventional studies. CARE-MND can act as a template for other neurological disorders.


Assuntos
Monitoramento Epidemiológico , Auditoria Médica , Doença dos Neurônios Motores/diagnóstico , Acesso à Informação , Pessoal Técnico de Saúde , Coleta de Dados , Atenção à Saúde/normas , Registros Eletrônicos de Saúde , Humanos , Monitorização Fisiológica , Enfermeiras e Enfermeiros , Participação do Paciente , Assistência Centrada no Paciente , Pesquisa , Escócia
12.
Proc Math Phys Eng Sci ; 472(2188): 20150500, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27274683

RESUMO

The non-destructive testing of austenitic welds using ultrasound plays an important role in the assessment of the structural integrity of safety critical structures. The internal microstructure of these welds is highly scattering and can lead to the obscuration of defects when investigated by traditional imaging algorithms. This paper proposes an alternative objective method for the detection of flaws embedded in austenitic welds based on the singular value decomposition of the time-frequency domain response matrices. The distribution of the singular values is examined in the cases where a flaw exists and where there is no flaw present. A lower threshold on the singular values, specific to austenitic welds, is derived which, when exceeded, indicates the presence of a flaw. The detection criterion is successfully implemented on both synthetic and experimental data. The datasets arising from welds containing a flaw are further interrogated using the decomposition of the time-reversal operator (DORT) method and the total focusing method (TFM), and it is shown that images constructed via the DORT algorithm typically exhibit a higher signal-to-noise ratio than those constructed by the TFM algorithm.

13.
Comput Methods Biomech Biomed Engin ; 15(10): 1081-92, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21604222

RESUMO

The prevalence of Parkinson's disease (PD) is increasing due to an ageing population. It is an unpredictable disease which requires regular assessment and monitoring. Current techniques used to assess PD are subjective. Clinicians observe movements made by a patient and subsequently rate the level of severity of, for example tremor or slowness of movement. Within this work, we have developed and evaluated a prototype computer-based assessment tool capable of collecting information on the movement difficulties present in PD. Twenty participants took part in an assessment of the tool, 10 of whom were diagnosed with PD and 10 were without the disease. Following the usage of the tool, it was found that there was a significant difference (p = 0.038) in the speed of movement between the two groups. We envisage that this tool could have the potential to enable more objective clinical conclusions to be made.


Assuntos
Periféricos de Computador , Diagnóstico por Computador/métodos , Transtornos dos Movimentos/diagnóstico , Transtornos dos Movimentos/fisiopatologia , Movimento , Doença de Parkinson/diagnóstico , Doença de Parkinson/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos dos Movimentos/etiologia , Doença de Parkinson/complicações , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Interface Usuário-Computador
14.
PLoS One ; 6(9): e25133, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21966436

RESUMO

Tree rings dominate millennium-long temperature reconstructions and many records originate from Scandinavia, an area for which the relative roles of external forcing and internal variation on climatic changes are, however, not yet fully understood. Here we compile 1,179 series of maximum latewood density measurements from 25 conifer sites in northern Scandinavia, establish a suite of 36 subset chronologies, and analyse their climate signal. A new reconstruction for the 1483-2006 period correlates at 0.80 with June-August temperatures back to 1860. Summer cooling during the early 17th century and peak warming in the 1930s translate into a decadal amplitude of 2.9°C, which agrees with existing Scandinavian tree-ring proxies. Climate model simulations reveal similar amounts of mid to low frequency variability, suggesting that internal ocean-atmosphere feedbacks likely influenced Scandinavian temperatures more than external forcing. Projected 21st century warming under the SRES A2 scenario would, however, exceed the reconstructed temperature envelope of the past 1,500 years.


Assuntos
Estações do Ano , Temperatura , Mudança Climática , Países Escandinavos e Nórdicos
15.
Environ Sci Technol ; 45(20): 8858-65, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21882858

RESUMO

Fourier transform infrared spectroscopy (FTIRS) can provide detailed information on organic and minerogenic constituents of sediment records. Based on a large number of sediment samples of varying age (0-340,000 yrs) and from very diverse lake settings in Antarctica, Argentina, Canada, Macedonia/Albania, Siberia, and Sweden, we have developed universally applicable calibration models for the quantitative determination of biogenic silica (BSi; n = 816), total inorganic carbon (TIC; n = 879), and total organic carbon (TOC; n = 3164) using FTIRS. These models are based on the differential absorbance of infrared radiation at specific wavelengths with varying concentrations of individual parameters, due to molecular vibrations associated with each parameter. The calibration models have low prediction errors and the predicted values are highly correlated with conventionally measured values (R = 0.94-0.99). Robustness tests indicate the accuracy of the newly developed FTIRS calibration models is similar to that of conventional geochemical analyses. Consequently FTIRS offers a useful and rapid alternative to conventional analyses for the quantitative determination of BSi, TIC, and TOC. The rapidity, cost-effectiveness, and small sample size required enables FTIRS determination of geochemical properties to be undertaken at higher resolutions than would otherwise be possible with the same resource allocation, thus providing crucial sedimentological information for climatic and environmental reconstructions.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Lagos
16.
Aviat Space Environ Med ; 81(8): 774-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20681238

RESUMO

INTRODUCTION: The high prevalence of low back pain (LBP) in helicopter pilots has been well documented, although the reason behind it remains unclear. To date, little research exists comparing the Royal Air Force (RAF) to civilian pilots. METHODS: A questionnaire inquiring into participant demographics, flying experience, and back pain was distributed to RAF pilots based at units around the United Kingdom and civilian pilots working for groups such as Air Ambulance and Her Majesty's Coastguards. RESULTS: RAF pilots were significantly younger than civilian pilots (mean age 38.9 +/- 8.8 yr and 47.1 +/- 9.2 yr, respectively) and had been flying for a mode length of 6-10 yr compared with +26 yr in civilian pilots. Of civilian pilots, 40% had previously served as a pilot in the military. Neither RAF (83%) nor civilian (81%) pilots were significantly more likely to suffer from LBP and the nature of the pain experienced was similar. There were 33% of RAF and 55% of civilian pilots who used a back support. DISCUSSION: The high prevalence of back pain reported by civilian and RAF pilots may be due to several factors. To investigate this further would require responses from a greater number of civilian pilots, particularly those who do not have previous military experience. In the meantime, further use of lumbar support may go some of the way to alleviating the problem.


Assuntos
Medicina Aeroespacial , Aeronaves , Dor Lombar/epidemiologia , Doenças Profissionais/epidemiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Reino Unido/epidemiologia
17.
Mar Pollut Bull ; 50(3): 264-75, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15757690

RESUMO

This study examined the effects of anthropogenic contaminants and environmental variables on the composition of benthic diatom communities within a contaminated bay adjacent to an abandoned waste disposal site in Antarctica. The combination of geographical, environmental and chemical data included in the study explained all of the variation observed within the diatom communities. The chemical data, particularly metal concentrations, explained 45.9% of variation in the diatom communities, once the effects of grain-size and spatial structure had been excluded. Of the metals, tin explained the greatest proportion of variation in the diatom communities (28%). Tin was very highly correlated (R2>0.95) with several other variables (copper, iron, lead, and sum of metals), all of which explained similarly high proportions of total variation. Grain-size data explained 23% of variation once the effects of spatial structure and the chemical data had been excluded. The pure spatial component explained only 1.8% of the total variance. The study demonstrates that much of the compositional variability observed in the bay can be explained by concentrations of metal contaminants.


Assuntos
Diatomáceas/crescimento & desenvolvimento , Intoxicação por Metais Pesados , Poluentes Químicos da Água/intoxicação , Regiões Antárticas , Monitoramento Ambiental , Hidrocarbonetos/intoxicação , Dinâmica Populacional
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