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1.
Sensors (Basel) ; 23(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36772709

RESUMO

Updating the road infrastructure requires the potential mass adoption of the road studs currently used in car detection, speed monitoring, and path marking. Road studs commonly include RF transceivers connecting the buried sensors to an offsite base station for centralized data management. Since traffic monitoring experiments through buried sensors are resource expensive and difficult, the literature detailing it is insufficient and inaccessible due to various strategic reasons. Moreover, as the main RF frequencies adopted for stud communication are either 868/915 MHz or 2.4 GHz, the radio coverage differs, and it is not readily predictable due to the low-power communication in the near proximity of the ground. This work delivers a reference study on low-power RF communication ranging for the two above frequencies up to 60 m. The experimental setup employs successive measurements and repositioning of a base station at three different heights of 0.5, 1 and 1.5 m, and is accompanied by an extensive theoretical analysis of propagation, including line of sight, diffraction, and wall reflection. Enhancing the tutorial value of this work, a correlation analysis using Pearson's coefficient and root mean square error is performed between the field test and simulation results.

3.
Eur Radiol ; 30(4): 1997-2009, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31844958

RESUMO

OBJECTIVE: To implement detailed EU cardiac computed tomography angiography (CCTA) quality criteria in the multicentre DISCHARGE trial (FP72007-2013, EC-GA 603266), we reviewed image quality and adherence to CCTA protocol and to the recommendations of invasive coronary angiography (ICA) in a pilot study. MATERIALS AND METHODS: From every clinical centre, imaging datasets of three patients per arm were assessed for adherence to the inclusion/exclusion criteria of the pilot study, predefined standards for the CCTA protocol and ICA recommendations, image quality and non-diagnostic (NDX) rate. These parameters were compared via multinomial regression and ANOVA. If a site did not reach the minimum quality level, additional datasets had to be sent before entering into the final accepted database (FADB). RESULTS: We analysed 226 cases (150 CCTA/76 ICA). The inclusion/exclusion criteria were not met by 6 of the 226 (2.7%) datasets. The predefined standard was not met by 13 of 76 ICA datasets (17.1%). This percentage decreased between the initial CCTA database and the FADB (multinomial regression, 53 of 70 vs 17 of 75 [76%] vs [23%]). The signal-to-noise ratio and contrast-to-noise ratio of the FADB did not improve significantly (ANOVA, p = 0.20; p = 0.09). The CTA NDX rate was reduced, but not significantly (initial CCTA database 15 of 70 [21.4%]) and FADB 9 of 75 [12%]; p = 0.13). CONCLUSION: We were able to increase conformity to the inclusion/exclusion criteria and CCTA protocol, improve image quality and decrease the CCTA NDX rate by implementing EU CCTA quality criteria and ICA recommendations. KEY POINTS: • Failure to meet protocol adherence in cardiac CTA was high in the pilot study (77.6%). • Image quality varies between sites and can be improved by feedback given by the core lab. • Conformance with new EU cardiac CT quality criteria might render cardiac CTA findings more consistent and comparable.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Reprodutibilidade dos Testes
4.
Health Qual Life Outcomes ; 18(1): 140, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32410687

RESUMO

BACKGROUND: Health-related quality of life (HRQoL) is impaired in patients with stable angina but patients often present with other forms of chest pain. The aim of this study was to compare the pre-diagnostic HRQoL in patients with suspected coronary artery disease (CAD) according to angina type, gender, and presence of obstructive CAD. METHODS: From the pilot study for the European DISCHARGE trial, we analysed data from 24 sites including 1263 patients (45.9% women, 61.1 ± 11.3 years) who were clinically referred for invasive coronary angiography (ICA; 617 patients) or coronary computed tomography angiography (CTA; 646 patients). Prior to the procedures, patients completed HRQoL questionnaires: the Short Form (SF)-12v2, the EuroQoL (EQ-5D-3 L) and the Hospital Anxiety and Depression Scale. RESULTS: Fifty-five percent of ICA and 35% of CTA patients had typical angina, 23 and 33% had atypical angina, 18 and 28% had non-anginal chest discomfort and 5 and 5% had other chest discomfort, respectively. Patients with typical angina had the poorest physical functioning compared to the other angina groups (SF-12 physical component score; 41.2 ± 8.8, 43.3 ± 9.1, 46.2 ± 9.0, 46.4 ± 11.4, respectively, all age and gender-adjusted p < 0.01), and highest anxiety levels (8.3 ± 4.1, 7.5 ± 4.1, 6.5 ± 4.0, 4.7 ± 4.5, respectively, all adjusted p < 0.01). On all other measures, patients with typical or atypical angina had lower HRQoL compared to the two other groups (all adjusted p < 0.05). HRQoL did not differ between patients with and without obstructive CAD while women had worse HRQoL compared with men, irrespective of age and angina type. CONCLUSIONS: Prior to a diagnostic procedure for stable chest pain, HRQoL is associated with chest pain characteristics, but not with obstructive CAD, and is significantly lower in women. TRIAL REGISTRATION: Clinicaltrials.gov, NCT02400229.


Assuntos
Angina Pectoris/fisiopatologia , Doença da Artéria Coronariana/fisiopatologia , Qualidade de Vida , Idoso , Angina Pectoris/classificação , Angina Pectoris/diagnóstico , Doença da Artéria Coronariana/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Distribuição por Sexo , Inquéritos e Questionários
6.
J Chem Educ ; 96(12): 2959-2967, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-32051645

RESUMO

Increasing demand for chemicals worldwide, depleting resources, consumer pressure, stricter legislation, and the rising cost of waste disposal are placing increasing pressure on chemical and related industries. For any organization to survive in the current arena of growing climate change laws and regulations, and increasing public influence, the issue of sustainability must be fundamental to the way it operates. A sustainable manufacturing approach will enable economic growth to be combined with environmental and social sustainability and will be realized via collaboration between a multidisciplinary community including chemists, biologists, engineers, environmental scientists, economists, experts in management, and policy makers. Hence, employees with new skills, knowledge, and experience are essential. To realize this approach, the design and development of a series of workshops encompassing systems thinking are presented here. After close consultation with industry, an annual program of interactive workshops has been designed for graduate students to go beyond examining the "greening" of chemical reactions, processes, and products, and instead embed a systems thinking approach to learning. The workshops provide a valuable insight into the issues surrounding sustainable manufacturing covering change management, commercialization, environmental impact, circular economy, legislation, and bioresources incorporating the conversion of waste into valuable products. The multidisciplinary course content incorporates industrial case studies, providing access to real business issues, and is delivered by experts from academic departments across campus and industry.

7.
Eur Radiol ; 27(7): 2957-2968, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27864607

RESUMO

OBJECTIVES: More than 3.5 million invasive coronary angiographies (ICA) are performed in Europe annually. Approximately 2 million of these invasive procedures might be reduced by noninvasive tests because no coronary intervention is performed. Computed tomography (CT) is the most accurate noninvasive test for detection and exclusion of coronary artery disease (CAD). To investigate the comparative effectiveness of CT and ICA, we designed the European pragmatic multicentre DISCHARGE trial funded by the 7th Framework Programme of the European Union (EC-GA 603266). METHODS: In this trial, patients with a low-to-intermediate pretest probability (10-60 %) of suspected CAD and a clinical indication for ICA because of stable chest pain will be randomised in a 1-to-1 ratio to CT or ICA. CT and ICA findings guide subsequent management decisions by the local heart teams according to current evidence and European guidelines. RESULTS: Major adverse cardiovascular events (MACE) defined as cardiovascular death, myocardial infarction and stroke as a composite endpoint will be the primary outcome measure. Secondary and other outcomes include cost-effectiveness, radiation exposure, health-related quality of life (HRQoL), socioeconomic status, lifestyle, adverse events related to CT/ICA, and gender differences. CONCLUSIONS: The DISCHARGE trial will assess the comparative effectiveness of CT and ICA. KEY POINTS: • Coronary artery disease (CAD) is a major cause of morbidity and mortality. • Invasive coronary angiography (ICA) is the reference standard for detection of CAD. • Noninvasive computed tomography angiography excludes CAD with high sensitivity. • CT may effectively reduce the approximately 2 million negative ICAs in Europe. • DISCHARGE addresses this hypothesis in patients with low-to-intermediate pretest probability for CAD.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Avaliação de Resultados em Cuidados de Saúde , Tomografia Computadorizada por Raios X/métodos , Idoso , Doença da Artéria Coronariana/economia , Análise Custo-Benefício , Europa (Continente) , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Qualidade de Vida , Estudos Retrospectivos
8.
Ann Bot ; 115(3): 353-68, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25617410

RESUMO

BACKGROUND AND AIMS: Sarcocornia comprises about 28 species of perennial succulent halophytes distributed worldwide, mainly in saline environments of warm-temperate and subtropical regions. The genus is characterized by strongly reduced leaves and flowers, which cause taxonomic difficulties; however, species in the genus show high diversity in growth form, with a mat-forming habit found in coastal salt marshes of all continents. Sarcocornia forms a monophyletic lineage with Salicornia whose species are all annual, yet the relationship between the two genera is poorly understood. This study is aimed at clarifying the phylogenetic relationship between Sarcocornia and Salicornia, interpreting biogeographical and ecological patterns in Sarcocornia, and gaining insights into putative parallel evolution of habit as an adaptation to environmental factors. METHODS: A comprehensively sampled and dated phylogeny of Sarcocornia is presented based on nuclear ribosomal DNA (external transcribed spacer) and chloroplast DNA (atpB-rbcL, rpl32-trnL) sequences; representative samples of Salicornia were also included in the analyses. To infer biogeographical patterns, an ancestral area reconstruction was conducted. KEY RESULTS: The Sarcocornia/Salicornia lineage arose during the Mid-Miocene from Eurasian ancestors and diversified into four subclades: the Salicornia clade, the American Sarcocornia clade, the Eurasian Sarcocornia clade and the South African/Australian Sarcocornia clade. Sarcocornia is supported as paraphyletic, with Salicornia nested within Sarcocornia being sister to the American/Eurasian Sarcocornia clade. The American and the South African/Australian Sarcocornia clade as well as the Salicornia clade were reconstructed to be of Eurasian origin. The prostrate, mat-forming habit arose multiple times in Sarcocornia. CONCLUSIONS: Sarcocornia diversified in salt-laden environments worldwide, repeatedly evolving superficially similar prostrate, mat-forming habits that seem advantageous in stressed environments with prolonged flooding, high tidal movement and frost. Some of these prostrate-habit types might be considered as ecotypes (e.g. S. pacifica or S. pillansii) while others represent good ecospecies (e.g. S. perennis, S. decumbens, S. capensis), hence representing different stages of speciation.


Assuntos
Amaranthaceae/classificação , Amaranthaceae/fisiologia , Evolução Biológica , DNA de Plantas/genética , Filogenia , Dispersão Vegetal , Plantas Tolerantes a Sal/fisiologia , Amaranthaceae/genética , DNA Intergênico/genética , Dados de Sequência Molecular , Tolerância ao Sal , Plantas Tolerantes a Sal/genética , Análise de Sequência de DNA
10.
BJR Open ; 5(1): 20220049, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37389005

RESUMO

Objective: Interstitial lung disease (ILD) is relatively common in patients with lung cancer with an incidence of 7.5%. Historically pre-existing ILD was a contraindication to radical radiotherapy owing to increased radiation pneumonitis rates, worsened fibrosis and poorer survival compared with non-ILD cohorts. Herein, the clinical and radiological toxicity outcomes of a contemporaneous cohort are described. Methods: Patients with ILD treated with radical radiotherapy for lung cancer at a regional cancer centre were collected prospectively. Radiotherapy planning, tumour characteristics, and pre- and post-treatment functional and radiological parameters were recorded. Cross-sectional images were independently assessed by two Consultant Thoracic Radiologists. Results: Twenty-seven patients with co-existing ILD received radical radiotherapy from February 2009 to April 2019, with predominance of usual interstitial pneumonia subtype (52%). According to ILD-GAP scores, most patients were Stage I. After radiotherapy, localised (41%) or extensive (41%) progressive interstitial changes were noted for most patients yet dyspnoea scores (n = 15 available) and spirometry (n = 10 available) were stable. One-third of patients with ILD went on to receive long-term oxygen therapy, which was significantly more than the non-ILD cohort. Median survival trended towards being worse compared with non-ILD cases (17.8 vs 24.0 months, p = 0.834). Conclusion: Radiological progression of ILD and reduced survival were observed post-radiotherapy in this small cohort receiving lung cancer radiotherapy, although a matched functional decline was frequently absent. Although there is an excess of early deaths, long-term disease control is achievable. Advances in knowledge: For selected patients with ILD, long-term lung cancer control without severely impacting respiratory function may be possible with radical radiotherapy, albeit with a slightly higher risk of death.

11.
Radiother Oncol ; 184: 109680, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37105303

RESUMO

BACKGROUND AND PURPOSE: Cardiac arrhythmia is a recognised potential complication of thoracic radiotherapy, but the responsible cardiac substructures for arrhythmogenesis have not been identified. Arrhythmogenic tissue is commonly located in the pulmonary veins (PVs) of cardiology patients with arrhythmia, however these structures are not currently considered organs-at-risk during radiotherapy planning. A standardised approach to their delineation was developed and evaluated. MATERIALS AND METHODS: The gross and radiological anatomy relevant to atrial fibrillation was derived from cardiology and radiology literature by a multidisciplinary team. A region of interest and contouring instructions for radiotherapy computed tomography scans were iteratively developed and subsequently evaluated. Radiation oncologists (n = 5) and radiation technologists (n = 2) contoured the PVs on the four-dimensional planning datasets of five patients with locally advanced lung cancer treated with 1.8-2.75 Gy fractions. Contours were compared to reference contours agreed by the researchers using geometric and dosimetric parameters. RESULTS: The mean dose to the PVs was 35% prescription dose. Geometric and dosimetric similarity of the observer contours with reference contours was fair, with an overall mean Dice of 0.80 ± 0.02. The right superior PV (mean DSC 0.83 ± 0.02) had better overlap than the left (mean DSC 0.80 ± 0.03), but the inferior PVs were equivalent (mean DSC of 0.78). The mean difference in mean dose was 0.79 Gy ± 0.71 (1.46% ± 1.25). CONCLUSION: A PV atlas with multidisciplinary approval led to reproducible delineation for radiotherapy planning, supporting the utility of the atlas in future clinical radiotherapy cardiotoxicity research encompassing arrhythmia endpoints.


Assuntos
Veias Pulmonares , Humanos , Veias Pulmonares/diagnóstico por imagem , Planejamento da Radioterapia Assistida por Computador/métodos , Coração , Tomografia Computadorizada por Raios X/métodos , Arritmias Cardíacas , Órgãos em Risco
12.
J Cardiothorac Surg ; 17(1): 126, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606861

RESUMO

BACKGROUND: Concomitant double valve pathology in the presence of severe MAC poses significant technical challenges when planning surgical intervention. With continued evolution of valve prosthesis, innovative techniques can be considered with the potential for additional therapeutic benefit. CASE PRESENTATION: We present a novel technique of using a rapid deployment surgical aortic valve in combination with open surgical transcatheter mitral valve implantation (TMVI) for severe Mitral Annular Calcification (MAC). The Intuity Elite rapid deployment prosthesis (Edwards Lifesciences, Irvine, CA) was used concomitantly with the Sapien 3 (Edwards Lifesciences, Irvine, CA) transcatheter prosthesis trans-atrially on cardiopulmonary bypass in a patient with critical aortic stenosis and moderate-severe mixed mitral valve disease in the setting of severe MAC (off-label use). CONCLUSIONS: We demonstrate how both technologies can, not only be accommodated, but indeed complement each other achieving an excellent outcome in a high-risk patient.


Assuntos
Estenose da Valva Aórtica , Calcinose , Doenças das Valvas Cardíacas , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Calcinose/cirurgia , Doenças das Valvas Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Valva Mitral/cirurgia , Desenho de Prótese , Resultado do Tratamento
13.
Gates Open Res ; 6: 12, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35965739

RESUMO

Background: The use of artificial insemination (AI) has great potential to improve smallholder dairy herds in Africa, however poor success and, in some situations, high costs in Kenya, have been discouraging.  Effective AI requires accurate oestrus detection and the measurement of progesterone (P4) can be used to indicate oestrus as well as non-pregnancy.  A cow-side progesterone lateral flow test, P4 Rapid, was evaluated as an aid to detect oestrus and non-pregnancy in Kenyan dairy cows, and assessed for association with AI efficiency.  Methods: A total of 527 cows were enrolled in the study, from two counties in central and southern Kenya.  Cattle in the test group (n = 308) were presented when suspected to be in oestrus and tested with the P4 Rapid (low P4 = oestrus, medium P4 = inconclusive, high P4 = not in oestrus/pregnant).  Cattle with low P4 were inseminated.  Cattle in the control group (n = 219) were inseminated when oestrus behaviour was detected i.e. standard practice. Results: Of the total P4 Rapid tests performed (n = 745), 1.5% were inconclusive, with the true accuracy of the test between 87-97%.  Conception rates were not significantly higher in the test group (83.9%) compared to the control group (77.9%). Abortion rates were not significantly different between the control (9.5%) and test groups (8.2%).  In the test group, 6.2% (19/308) cows showed a medium or high P4 level on day 0 and nine of these were subsequently found to have been already pregnant. Conclusions: The data indicated that the P4 Rapid test can be a useful tool to assist farmer decision-making in the confirmation of correct timing for AI, and importantly may avoid unnecessary inseminations in pregnant animals, thus reducing the risk of AI-induced abortion.

14.
Nutr Bull ; 47(1): 106-114, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-36045085

RESUMO

This paper provides an outline of a new interdisciplinary project called FixOurFood, funded through UKRI's 'Transforming UK food systems' programme. FixOurFood aims to transform the Yorkshire food system to a regenerative food system and will work to answer two main questions: (1) What do regenerative food systems look like? (2) How can transformations be enabled so that we can achieve a regenerative food system? To answer these questions, FixOurFood will work with diverse stakeholders to change the Yorkshire food system and use the learning to inform change efforts in other parts of the UK and beyond. Our work will focus on shifting trajectories towards regenerative dynamics in three inter-related systems of: healthy eating for young children, hybrid food economies and regenerative farming. We do this by a set of action-orientated interventions in schools and the food economy, metrics, policies and deliverables that can be applied in Yorkshire and across the UK. This article introduces the FixOurFood project and concludes by assessing the potential impact of these interventions and the importance we attach to working with stakeholders in government, business, third sector and civil society.


Assuntos
Dieta Saudável , Instituições Acadêmicas , Criança , Pré-Escolar , Comércio , Alimentos , Governo , Humanos
15.
JTCVS Tech ; 10: 254-261, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34977731

RESUMO

BACKGROUND: Transcatheter mitral valve implantation (TMVI) for native mitral valve pathology with severe mitral annular calcification has emerged as an alternative treatment option to conventional mitral valve surgery. The objective of this study was to evaluate patients who were referred for TMVI with severe mitral annular calcification and their procedural outcomes. METHODS: Retrospective analysis of patients from 2017 to 2020 referred for TMVI was carried out. Demographic characteristic details; surgical strategy; perioperative complications; and hospital stay, including 30-day and 1-year mortality, were analyzed. RESULTS: Eleven patients were referred for consideration of TMVI. The 8 patients who underwent TMVI had a median age of 74 years (range, 57-80 years), the median Society of Thoracic Surgeons score was 4.6 (range, 2.4-10.9), and European System for Cardiac Operative Risk Evaluation II score was 5.2% (2%-10.1%). The median cardiopulmonary bypass time and crossclamp times were 170 minutes (range, 150-248 minutes) and 152 minutes (range, 118-214 minutes), respectively. The median hospital stay was 29 days (range, 2-40 days). Thirty-day in hospital mortality was 12%, whereas 1-year mortality was 25%. There was symptomatic improvement with downgrade of New York Heart Association functional class from III or IV to I or II. The 3 patients who were turned down had a median age of 73 years, median Society of Thoracic Surgeons score was 13.4, and median European System for Cardiac Operative Risk Evaluation II score was 5.72%. They were alive at 12 months follow-up from the date of surgical assessment; however, all with New York Heart Association functional class III or IV symptoms. CONCLUSIONS: We describe a series demonstrating the technical consideration and capability of transatrial TMVI to treat mitral annular calcification and native mitral valve disease. Our results are favorable when compared with TMVI global registry data for transseptal or transapical approach.

16.
Radiol Case Rep ; 15(7): 950-954, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32419893

RESUMO

Aortoenteric fistula (AEF) is a rare but potentially fatal condition causing massive gastrointestinal bleeding. It is defined as fistulous communication between the gastrointestinal tract and the aorta which is sub classified into primary and secondary. Primary AEF refers to communication between a native aorta and the gastrointestinal tract. Secondary AEF is a communication between a reconstructed aorta, which includes open or endovascular repair, with the gastrointestinal tract. We herein describe an unusual case of secondary AEF in an 88-year-old gentleman. Our case is unusual as secondary AEF involving the rectum has rarely been reported in the literature.

17.
Gait Posture ; 27(1): 36-42, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17267222

RESUMO

Foot orthotics (FO) may be prescribed for a range of lower limb and foot conditions. Prior studies report use of FO in enhancing postural stability in healthy younger adults, and do not control for footwear type. Currently, interest in the effects of FO on postural stability in older adults has increased. Limited reports exist of the effects on postural stability of FO made of combinations of materials, thicknesses and surface textures. In this study 40 healthy females (51.1+/-5.8 years) recruited into a within subject test-retest randomised clinical trial were provided with identical footwear and randomised into four FO conditions (control, grid, dimple and plain, n=10 for each condition). Participants wore the footwear for 4 weeks, a minimum of 6h/day. A Kistler force plate was used to determine postural stability variables (anterior-posterior displacements and medial-lateral displacements) for each participant in a static position, with eyes open and eyes closed. Base of support was evaluated using the GAITRite system. Each outcome measure was measured at baseline and 4 weeks. Postural stability variables demonstrated no significant differences between the four FO conditions. No significant differences were observed with base of support between the four conditions. We have demonstrated no detrimental effects on postural stability in older females after 4 weeks. This is regardless of orthotic texture and is independent of footwear. Biomechanical or sensory effects of FO on postural stability are still to be determined. These may be dependent on the geometry and texture of the orthotic.


Assuntos
, Aparelhos Ortopédicos , Equilíbrio Postural/fisiologia , Postura/fisiologia , Caminhada/fisiologia , Fenômenos Biomecânicos , Desenho de Equipamento , Feminino , Seguimentos , Marcha/fisiologia , Humanos , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Projetos Piloto , Polivinil/química , Estudos Prospectivos , Sapatos , Método Simples-Cego , Propriedades de Superfície , Visão Ocular/fisiologia
18.
Am J Cardiol ; 121(1): 9-13, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29103607

RESUMO

Fractional flow reserve (FFR) derived from coronary computed tomography angiography (CTA) is a new technique for the diagnosis of ischemic coronary artery stenoses. The aim of this prospective study was to evaluate the diagnostic performance of a novel on-site computed tomography-based fractional flow reserve algorithm (CT-FFR) compared with invasive FFR as the gold standard, and to determine whether its diagnostic performance is affected by interobserver variations in lumen segmentation. We enrolled 44 consecutive patients (64.6 ± 8.9 years, 34% female) with 60 coronary atherosclerotic lesions who underwent coronary CTA and invasive coronary angiography in 2 centers. An FFR value ≤0.8 was considered significant. Coronary CTA scans were evaluated by 2 expert readers, who manually adjusted the semiautomated coronary lumen segmentations for effective diameter stenosis (EDS) assessment and on-site CT-FFR simulation. The mean CT-FFR value was 0.77 ± 0.15, whereas the mean EDS was 43.6 ± 16.9%. The sensitivity, specificity, positive predictive value, and negative predictive value of CT-FFR versus EDS with a cutoff of 50% were the following: 91%, 72%, 63%, and 93% versus 52%, 87%, 69%, and 77%, respectively. The on-site CT-FFR demonstrated significantly better diagnostic performance compared with EDS (area under the curve 0.89 vs 0.74, respectively, p <0.001). The CT-FFR areas under the curve of the 2 readers did not show any significant difference (0.89 vs 0.88, p = 0.74). In conclusion, on-site CT-FFR simulation is feasible and has better diagnostic performance than anatomic stenosis assessment. Furthermore, the diagnostic performance of the on-site CT-FFR simulation algorithm does not depend on the readers' semiautomated lumen segmentation adjustments.


Assuntos
Algoritmos , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/fisiopatologia , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Tomografia Computadorizada Multidetectores , Idoso , Angiografia Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes
19.
Int J Antimicrob Agents ; 30 Suppl 2: S113-7, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17997283

RESUMO

By the 1960s and 1970s, problems in the antibacterial treatment of infections had begun to emerge. Previously active antibacterials were being compromised by the development of resistance. Beta-lactamase production was identified in isolates of staphylococci, and, amongst others, in Escherichia coli, Proteus mirabilis, Haemophilus influenzae and Moraxella catarrhalis. The discovery of the potent beta-lactamase inhibitor clavulanic acid, and its protective effect on amoxicillin, a semi-synthetic penicillin with good oral absorption and potent broad-spectrum antimicrobial activity, was thus of great importance in the treatment of bacterial disease. Following preliminary clinical studies in bronchitis and urinary tract infections, amoxicillin/clavulanate therapy was investigated in a wide range of infections and proved to demonstrate a high level of clinical efficacy. These results supported the launch of amoxicillin/clavulanate (Augmentin) in 1981 for use in upper and lower respiratory tract infections, urinary tract infections, skin and soft tissue infections and obstetric, gynaecological and intra-abdominal infections.


Assuntos
Combinação Amoxicilina e Clavulanato de Potássio/história , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Combinação Amoxicilina e Clavulanato de Potássio/farmacologia , Antibacterianos/farmacologia , História do Século XX , História do Século XXI , Humanos , Resistência beta-Lactâmica/efeitos dos fármacos , Inibidores de beta-Lactamases
20.
Int J Antimicrob Agents ; 30 Suppl 2: S139-41, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18029150

RESUMO

Since most infectious microorganisms inevitably develop resistance to any agents used to combat them, there has been a constant need to produce improved, more potent, antimicrobials. At least in part, the emergence and spread of resistant organisms has been provoked by inappropriate over-use of antibacterials. In the last decade, many fewer new antibacterials have been developed but overall prescribing has continued to increase. Consensus prescribing principles have now been defined with the aim of optimising therapy and preventing further increases in, or even to prompt a reduction in, the prevalence of resistance to antibacterial agents. Whilst it is important to encourage continued development of new classes of antibacterials, it is also vital to make the best use of available agents. The development of new dosages and formulations of amoxicillin/clavulanate allows this agent to continue to fill the important role in therapy which it has occupied, and continues to occupy, 25 years after it was launched.


Assuntos
Combinação Amoxicilina e Clavulanato de Potássio/história , Combinação Amoxicilina e Clavulanato de Potássio/farmacologia , Antibacterianos/história , Antibacterianos/farmacologia , Infecções Bacterianas/tratamento farmacológico , Farmacorresistência Bacteriana , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Antibacterianos/uso terapêutico , Infecções Bacterianas/microbiologia , História do Século XX , História do Século XXI , Humanos
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