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1.
Chemistry ; 28(1): e202102968, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34786768

RESUMO

Examination of the reactions of σ-type quinolinium-based triradicals with cyclohexane in the gas phase demonstrated that the radical site that is the least strongly coupled to the other two radical sites reacts first, independent of the intrinsic reactivity of this radical site, in contrast to related biradicals that first react at the most electron-deficient radical site. Abstraction of one or two H atoms and formation of an ion that formally corresponds to a combination of the ion and cyclohexane accompanied by elimination of a H atom ("addition-H") were observed. In all cases except one, the most reactive radical site of the triradicals is intrinsically less reactive than the other two radical sites. The product complex of the first H atom abstraction either dissociates to give the H-atom-abstraction product and the cyclohexyl radical or the more reactive radical site in the produced biradical abstracts a H atom from the cyclohexyl radical. The monoradical product sometimes adds to cyclohexene followed by elimination of a H atom, generating the "addition-H" products. Similar reaction efficiencies were measured for three of the triradicals as for relevant monoradicals. Surprisingly, the remaining three triradicals (all containing a meta-pyridyne moiety) reacted substantially faster than the relevant monoradicals. This is likely due to the exothermic generation of a meta-pyridyne analog that has enough energy to attain the dehydrocarbon atom separation common for H-atom-abstraction transition states of protonated meta-pyridynes.

2.
J Clin Microbiol ; 48(8): 2677-82, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20519459

RESUMO

To develop an immunofluorescence assay for identification of the 2009 H1N1 influenza A virus, we generated a number of monoclonal antibodies (MAbs) by using inactivated H1N1 2009 virus (A/California/07/2009) as the immunogen. Two MAbs that target two different epitopes of the 2009 H1N1 hemagglutinin (HA) were selected to make the D(3) Ultra 2009 H1N1 Influenza A ID kit (2009 H1N1 ID kit; Diagnostic Hybrids, Inc., Athens, OH), which is intended for the identification of the 2009 H1N1 virus by indirect immunofluorescence assay (IFA). The kit does not detect any of 14 seasonal H1N1 or H3N2 prototype influenza virus strains and is also not reactive with seven other major respiratory viruses. Clinical respiratory specimens were evaluated using both the 2009 H1N1 ID kit and the CDC human influenza virus real-time reverse transcription-PCR swine flu panel (CDC rRT-PCR) and showed 100% agreement between the two assays. Four of these clinical specimens, however, were positive by the 2009 H1N1 ID kit but were identified as presumptively positive by the CDC rRT-PCR by virtue of showing threshold cycle (C(T)) values only with universal InfA and swInfA primers, not with swH1 primers. Sequence analysis of the HA genes of these four specimens revealed point mutations in both the primer and probe regions. In addition, unlike the CDC rRT-PCR, the 2009 H1N1 ID kit can differentiate the 2009 H1N1 virus from a swine-derived H1 influenza A virus (A/New Jersey/8/76). The 2009 H1N1 ID kit offers clinical laboratories an alternative to RT-PCR for the identification of the 2009 H1N1 influenza A virus.


Assuntos
Anticorpos Monoclonais , Anticorpos Antivirais , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/diagnóstico , Influenza Humana/virologia , Virologia/métodos , Animais , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Antivirais/isolamento & purificação , Primers do DNA/genética , Hemaglutininas Virais/imunologia , Humanos , Imunoensaio/métodos , Vírus da Influenza A Subtipo H1N1/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Sondas de Oligonucleotídeos/genética , Mutação Puntual , RNA Viral/genética , Kit de Reagentes para Diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade
3.
BMJ Open ; 7(10): e016355, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28982816

RESUMO

OBJECTIVE: Reconfiguration of trauma services, with direct transport of patients with traumatic brain injury (TBI) to specialist neuroscience centres (SNCs)-bypassing non-specialist acute hospitals (NSAHs), could improve outcomes. However, delays in stabilisation of airway, breathing and circulation (ABC) may worsen outcomes when compared with selective secondary transfer from nearest NSAH to SNC. We conducted a pilot cluster randomised controlled trial to determine the feasibility and plausibility of bypassing suspected patients with TBI -directly into SNCs-producing a measurable effect. SETTING: Two English Ambulance Services. PARTICIPANTS: 74 clusters (ambulance stations) were randomised within pairs after matching for important characteristics. Clusters enrolled head-injured adults-injured nearest to an NSAH-with internationally accepted TBI risk factors and stable ABC. We excluded participants attended by Helicopter Emergency Medical Services or who were injured more than 1 hour by road from nearest SNC. INTERVENTIONS: Intervention cluster participants were transported directly to an SNC bypassing nearest NSAH; control cluster participants were transported to nearest NSAH with selective secondary transfer to SNC. OUTCOMES: Trial recruitment rate (target n=700 per annum) and percentage with TBI on CT scan (target 80%) were the primary feasibility outcomes. 30-day mortality, 6-month Extended Glasgow Outcome Scale and quality of life were secondary outcomes. RESULTS: 56 ambulance station clusters recruited 293 patients in 12 months. The trial arms were similar in terms of age, conscious level and injury severity. Less than 25% of recruited patients had TBI on CT (n=70) with 7% (n=20) requiring neurosurgery. Complete case analysis showed similar 30-day mortality in the two trial arms (control=8.8 (2.7-14.0)% vs intervention=9.4(2.3-14.0)%). CONCLUSION: Bypassing patients with suspected TBI to SNCs gives an overtriage (false positive) ratio of 13:1 for neurosurgical intervention and 4:1 for TBI. A measurable effect from a full trial of early neuroscience care following bypass is therefore unlikely. TRIAL REGISTRATION NUMBER: ISRCTN68087745.


Assuntos
Lesões Encefálicas Traumáticas/cirurgia , Hospitais Especializados/estatística & dados numéricos , Transporte de Pacientes , Centros de Traumatologia , Adulto , Idoso , Ambulâncias , Serviços Médicos de Emergência , Reações Falso-Positivas , Feminino , Escala de Resultado de Glasgow , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Projetos Piloto , Qualidade de Vida , Viagem , Reino Unido
4.
Health Technol Assess ; 20(1): 1-198, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26753808

RESUMO

BACKGROUND: Reconfiguration of trauma services, with direct transport of traumatic brain injury (TBI) patients to neuroscience centres (NCs), bypassing non-specialist acute hospitals (NSAHs), could potentially improve outcomes. However, delays in stabilisation of airway, breathing and circulation (ABC) and the difficulties in reliably identifying TBI at scene may make this practice deleterious compared with selective secondary transfer from nearest NSAH to NC. National Institute for Health and Care Excellence guidance and systematic reviews suggested equipoise and poor-quality evidence - with regard to 'early neurosurgery' in this cohort - which we sought to address. METHODS: Pilot cluster randomised controlled trial of bypass to NC conducted in two ambulance services with the ambulance station (n = 74) as unit of cluster [Lancashire/Cumbria in the North West Ambulance Service (NWAS) and the North East Ambulance Service (NEAS)]. Adult patients with signs of isolated TBI [Glasgow Coma Scale (GCS) score of < 13 in NWAS, GCS score of < 14 in NEAS] and stable ABC, injured nearest to a NSAH were transported either to that hospital (control clusters) or bypassed to the nearest NC (intervention clusters). PRIMARY OUTCOMES: recruitment rate, protocol compliance, selection bias as a result of non-compliance, accuracy of paramedic TBI identification (overtriage of study inclusion criteria) and pathway acceptability to patients, families and staff. 'Open-label' secondary outcomes: 30-day mortality, 6-month Extended Glasgow Outcome Scale (GOSE) and European Quality of Life-5 Dimensions. RESULTS: Overall, 56 clusters recruited 293 (169 intervention, 124 control) patients in 12 months, demonstrating cluster randomised pre-hospital trials as viable for heath service evaluations. Overall compliance was 62%, but 90% was achieved in the control arm and when face-to-face paramedic training was possible. Non-compliance appeared to be driven by proximity of the nearest hospital and perceptions of injury severity and so occurred more frequently in the intervention arm, in which the perceived time to the NC was greater and severity of injury was lower. Fewer than 25% of recruited patients had TBI on computed tomography scan (n = 70), with 7% (n = 20) requiring neurosurgery (craniotomy, craniectomy or intracranial pressure monitoring) but a further 18 requiring admission to an intensive care unit. An intention-to-treat analysis revealed the two trial arms to be equivalent in terms of age, GCS and severity of injury. No significant 30-day mortality differences were found (8.8% vs. 9.1/%; p > 0.05) in the 273 (159/113) patients with data available. There were no apparent differences in staff and patient preferences for either pathway, with satisfaction high with both. Very low responses to invitations to consent for follow-up in the large number of mild head injury-enrolled patients meant that only 20% of patients had 6-month outcomes. The trial-based economic evaluation could not focus on early neurosurgery because of these low numbers but instead investigated the comparative cost-effectiveness of bypass compared with selective secondary transfer for eligible patients at the scene of injury. CONCLUSIONS: Current NHS England practice of bypassing patients with suspected TBI to neuroscience centres gives overtriage ratios of 13 : 1 for neurosurgery and 4 : 1 for TBI. This important finding makes studying the impact of bypass to facilitate early neurosurgery not plausible using this study design. Future research should explore an efficient comparative effectiveness design for evaluating 'early neurosurgery through bypass' and address the challenge of reliable TBI diagnosis at the scene of injury. TRIAL REGISTRATION: Current Controlled Trials ISRCTN68087745. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 1. See the NIHR Journals Library website for further project information.


Assuntos
Desvio de Ambulâncias/economia , Lesões Encefálicas , Neurocirurgia/economia , Triagem/economia , Adulto , Pessoal Técnico de Saúde , Ambulâncias , Lesões Encefálicas/economia , Lesões Encefálicas/cirurgia , Análise Custo-Benefício , Inglaterra , Estudos de Viabilidade , Escala de Coma de Glasgow , Hospitais , Humanos , Satisfação do Paciente , Projetos de Pesquisa , Avaliação da Tecnologia Biomédica
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