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1.
Colorectal Dis ; 22(3): 342-345, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31652389

RESUMO

AIM: Bowel preservation is paramount in Crohn's disease surgery as affected patients are typically young adults at risk of having several abdominal surgical procedures during their lifetime. Intra-operative assessment of the extent and location of Crohn's disease is not standardized and is left to a mixture of the surgeon's experience, tactile feedback, macroscopic appearance and preoperative imaging. The aim of this study was to describe the technical steps of a standardized protocol for intra-operative ultrasound assessment of the small bowel in patients undergoing surgery for ileocolic Crohn's disease. METHOD: After laparoscopic mobilization of the bowel, a periumbilical incision is performed for extracorporeal division of the mesentery and the resection and anastomosis. A gastrointestinal consultant radiologist, with expertise in Crohn's disease imaging and abdominal ultrasound, performs full intra-operative assessment of the small bowel by applying a sterile ultrasound probe directly to the bowel, prior to resection being performed by the surgeon. The bowel is assessed through the wound protector with a sterile technique and the length, location and number of segments is documented together with further quantitative assessment using the METRIC (MR enterography or ultrasound in Crohn's disease) scoring guide. RESULTS: A step-by-step protocol for intra-operative ultrasound evaluation of the entire small bowel is described. CONCLUSIONS: A standardized approach to intra-operative evaluation of the extent and location of Crohn's disease is desirable. Intra-operative ultrasound may provide added value for assessment of proximal and multifocal Crohn's disease.


Assuntos
Doença de Crohn , Laparoscopia , Anastomose Cirúrgica , Doença de Crohn/diagnóstico por imagem , Doença de Crohn/cirurgia , Humanos , Intestino Delgado/diagnóstico por imagem , Intestino Delgado/cirurgia , Ultrassonografia , Adulto Jovem
2.
Tech Coloproctol ; 24(9): 965-969, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32577847

RESUMO

BACKGROUND: Intraoperative assessment of the extent and location of Crohn's disease is not standardised and relies on a mixture of surgeons' experience, tactile feedback and macroscopic appearance. To overcome this variability, we developed a protocol for full intraoperative ultrasound scan of the small bowel and we here report the results of "Assessing the Feasibility and Safety of Using Intraoperative Ultrasound in Ileocolic Crohn's Disease-The IUSS CROHN Study". METHODS: This is a prospective single centre observational study with enrolment of all patients undergoing elective surgery for terminal ileal Crohn's disease from January 2019 to March 2020. Patients underwent laparoscopic ileocolic resection, according to a standardised technique. Ultrasound intraoperative quantitative assessment was performed according to the METRIC (MREnterography or ulTRasound in Crohn's disease) scoring guide. RESULTS: Intraoperative ultrasound was successfully performed in 6 patients from the ileocaecal valve to the proximal jejunum. The median time required was 23.5 min (range 17-37 min) as compared to 6.5 min (5-12 min) required for the macroscopic evaluation performed by the surgeon. In 3 patients, intraoperative ultrasound identified more disease than surgical evaluation. CONCLUSIONS: This feasibility study demonstrated the safety of intraoperative ultrasound and allowed the development of a standardised protocol for intraoperative ultrasound and the data collection required to inform a randomised multicentre study.


Assuntos
Doença de Crohn , Laparoscopia , Doença de Crohn/diagnóstico por imagem , Doença de Crohn/cirurgia , Estudos de Viabilidade , Humanos , Íleo , Intestino Delgado/diagnóstico por imagem , Intestino Delgado/cirurgia , Estudos Prospectivos
6.
Anim Genet ; 43(3): 239-49, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22486494

RESUMO

The major histocompatibility complex (MHC) is one of the most diverse regions of the mammalian genome. Diversity in MHC genes is integral to their function in the immune system, and while pathogens play a key role in shaping this diversity, the contribution of other selective forces remains unclear. The controlled breeding of cattle offers an excellent model for the identification and exploration of these forces. We characterized the MHC class I genes present in a sample of Canadian Holstein A.I. bulls and compared the results with those obtained in an earlier study. No evidence for a reduction in MHC diversity over 20 years was observed, but the relative frequency of some haplotypes had changed: the formerly rare A12 (w12B) haplotype had become the most common, together with A15, while A19, which dominated the earlier sample, had significantly reduced in frequency. Only 7% of bulls in the current study were MHC homozygous compared with the 14% expected under Hardy-Weinberg. To identify the selective forces at work, a gene substitution model was used to calculate the effects of MHC on selection traits using estimated breeding values for each bull. Significant associations between MHC and production, disease and fertility traits were identified, suggesting that MHC diversity is not merely shaped by disease in this controlled breeding system. The decrease in a common haplotype, the reduced number of homozygous bulls and the associations with disease and production traits together indicate that MHC diversity in dairy cattle is maintained by heterozygote advantage.


Assuntos
Genes MHC Classe I/genética , Polimorfismo Genético , Seleção Genética , Animais , Cruzamento , Canadá , Bovinos , Indústria de Laticínios , Aptidão Genética , Haplótipos , Endogamia , Masculino , Modelos Genéticos , Fenótipo , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Fatores de Tempo
7.
Epidemics ; 39: 100569, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35597098

RESUMO

The effort for combating the COVID-19 pandemic around the world has resulted in a huge amount of data, e.g., from testing, contact tracing, modelling, treatment, vaccine trials, and more. In addition to numerous challenges in epidemiology, healthcare, biosciences, and social sciences, there has been an urgent need to develop and provide visualisation and visual analytics (VIS) capacities to support emergency responses under difficult operational conditions. In this paper, we report the experience of a group of VIS volunteers who have been working in a large research and development consortium and providing VIS support to various observational, analytical, model-developmental, and disseminative tasks. In particular, we describe our approaches to the challenges that we have encountered in requirements analysis, data acquisition, visual design, software design, system development, team organisation, and resource planning. By reflecting on our experience, we propose a set of recommendations as the first step towards a methodology for developing and providing rapid VIS capacities to support emergency responses.


Assuntos
COVID-19 , COVID-19/epidemiologia , Busca de Comunicante , Humanos , Pandemias
8.
Radiography (Lond) ; 27 Suppl 1: S14-S19, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34274226

RESUMO

OBJECTIVES: To explain what a clinical academic career can be, what it can lead to for the individual, profession and most importantly the patient, and why these roles are so important to radiography. KEY FINDINGS: Multiple challenges to the adoption of clinical academic careers exist, including achievable measurable outcomes, visibility & senior support, and balancing different time demands. Equally the rewards are wide ranging and can advance both the individual and profession through role extension opportunities, increased career progression, patient benefits, and academic and research skills. CONCLUSION: Clinical academic careers can provide advantages for the individual, department, profession and most importantly the patient with advanced clinical practice through evidenced based research. IMPLICATIONS FOR PRACTICE: Improving clinical academic careers within Radiography will promote research participation and increase radiographic roles in patient-centred research delivery and development. Combining evidenced based research with academic skills will lead to improved patient care and better clinical outcomes.


Assuntos
Pessoal Técnico de Saúde , Recompensa , Humanos
9.
Nat Commun ; 12(1): 6539, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34764314

RESUMO

In antiferromagnetic spintronics, the read-out of the staggered magnetization or Néel vector is the key obstacle to harnessing the ultra-fast dynamics and stability of antiferromagnets for novel devices. Here, we demonstrate strong exchange coupling of Mn2Au, a unique metallic antiferromagnet that exhibits Néel spin-orbit torques, with thin ferromagnetic Permalloy layers. This allows us to benefit from the well-established read-out methods of ferromagnets, while the essential advantages of antiferromagnetic spintronics are only slightly diminished. We show one-to-one imprinting of the antiferromagnetic on the ferromagnetic domain pattern. Conversely, alignment of the Permalloy magnetization reorients the Mn2Au Néel vector, an effect, which can be restricted to large magnetic fields by tuning the ferromagnetic layer thickness. To understand the origin of the strong coupling, we carry out high resolution electron microscopy imaging and we find that our growth yields an interface with a well-defined morphology that leads to the strong exchange coupling.

10.
J Evol Biol ; 23(7): 1570-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20524952

RESUMO

In their recent article, Albertin et al. (2009) suggest an autotetraploid origin of 10 tetraploid strains of baker's yeast (Saccharomyces cerevisiae), supported by the frequent observation of double reduction meiospores. However, the presented inheritance results were puzzling and seemed to contradict the authors' interpretation that segregation ratios support a tetrasomic model of inheritance. Here, we provide an overview of the expected segregation ratios at the tetrad and meiospore level given scenarios of strict disomic and tetrasomic inheritance, for cases with and without recombination between locus and centromere. We also use a power analysis to derive adequate sample sizes to distinguish alternative models. Closer inspection of the Albertin et al. data reveals that strict disomy can be rejected in most cases. However, disomic inheritance with strong but imperfect preferential pairing could not be excluded with the sample sizes used. The possibility of tetrad analysis in tetraploid yeast offers a valuable opportunity to improve our understanding of meiosis and inheritance of tetraploids.


Assuntos
Segregação de Cromossomos/genética , Padrões de Herança/genética , Modelos Genéticos , Poliploidia , Saccharomyces cerevisiae/genética , Troca Genética/genética
11.
Vaccine ; 37(37): 5515-5524, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31405637

RESUMO

Foot-and-mouth disease (FMD) vaccines must be carefully selected and their application closely monitored to optimise their effectiveness. This review covers serological techniques for FMD vaccine quality control, including potency testing, vaccine matching and post-vaccination monitoring. It also discusses alternative laboratory procedures, such as antigen quantification and nucleotide sequencing, and briefly compares the approaches for FMD with those for measuring protection against influenza virus, where humoral immunity is also important. Serology is widely used to predict the protection afforded by vaccines and has great practical utility but also limitations. Animals differ in their responses to vaccines and in the protective mechanisms that they develop. Antibodies have a variety of properties and tests differ in what they measure. Antibody-virus interactions may vary between virus serotypes and strains and protection may be affected by the vaccination regime and the nature and timing of field virus challenge. Finally, tests employing biological reagents are difficult to standardise, whilst cross-protection data needed for test calibration and validation are scarce. All of this is difficult to reconcile with the desire for simple and universal criteria and thresholds for evaluating vaccines and vaccination responses and means that oversimplification of test procedures and their interpretation can lead to poor predictions. A holistic approach is therefore recommended, considering multiple sources of field, experimental and laboratory data. New antibody avidity and isotype tests seem promising alternatives to evaluate cross-protective, post-vaccination serological responses, taking account of vaccine potency as well as match. After choosing appropriate serological tests or test combinations and cut-offs, results should be interpreted cautiously and in context. Since opportunities for experimental challenge studies of cross-protection are limited and the approaches incompletely reflect real life, more field studies are needed to quantify cross-protection and its correlation to in vitro measurements.


Assuntos
Vírus da Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , Vacinação , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Proteção Cruzada/imunologia , Testes de Neutralização , Testes Sorológicos , Potência de Vacina
12.
Postgrad Med J ; 84(990): 220-2, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18424581

RESUMO

The case is reported of a 68-year-old man with perinuclear anti-neutrophil cytoplasmic antibody (pANCA)-associated glomerulonephritis who developed antibodies to glomerular basement membrane (anti-GBM) resulting in end stage renal failure. His pANCA titre on admission was 1:1024 IgG and he was anti-myeloperoxidase positive. A renal biopsy showed advanced sclerosing necrotising glomerulonephritis consistent with a pauci-immune ANCA-positive glomerulonephritis. He was treated with steroids and cyclophosphamide. His serum creatinine profile improved. He had a relapse of disease 16 months later, which was successfully treated. After a further 16 months, he presented with acute renal failure (creatinine 1060 micromol/l). His pANCA titre on admission was 1:64 IgG. This was treated as a further relapse of ANCA-positive vasculitis. He became oliguric and his haemoglobin concentration fell. Eight days after admission, he was found to be strongly positive for anti-GBM (138 U/ml). Despite receiving cyclophosphamide, steroids and plasma exchange, he remained dialysis-dependent.


Assuntos
Injúria Renal Aguda/etiologia , Anticorpos Anticitoplasma de Neutrófilos/sangue , Autoanticorpos/sangue , Glomerulonefrite/etiologia , Vasculite/etiologia , Idoso , Humanos , Masculino
13.
J Phys Condens Matter ; 30(46): 465802, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30280698

RESUMO

Lateral spin valves are attractive device geometries where functional spin currents can be generated and detected by various mechanisms, such as spin injection and the direct and the inverse spin Hall effect. To understand the mechanisms behind these effects better, as well as their potential for application in devices, we combine multiple mechanisms in multi-terminal Pt-Py-Cu lateral spin valves: we generate pure spin currents in the copper spin conduit both via the spin Hall effect in platinum and electric spin injection from permalloy and detect signals both via conventional non-local detection and via the inverse spin Hall effect in the same device at variable temperatures. Differences are observed, which we explain by the different spin injection and detection mechanisms, revealing their importance for the temperature dependence, which is not just governed by the spin transport in the conduit as previously claimed. By determining a different sensitivity of the observed effects on the interfaces, we highlight the importance of the exact current path for the device operation.

14.
J Phys Condens Matter ; 29(8): 085802, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28001132

RESUMO

We investigate the pure spin-current assisted depinning of magnetic domain walls in half ring based Py/Al lateral spin valve structures. Our optimized geometry incorporating a patterned notch in the detector electrode, directly below the Al spin conduit, provides a tailored pinning potential for a transverse domain wall and allows for a precise control over the magnetization configuration and as a result the domain wall pinning. Due to the patterned notch, we are able to study the depinning field as a function of the applied external field for certain applied current densities and observe a clear asymmetry for the two opposite field directions. Micromagnetic simulations show that this can be explained by the asymmetry of the pinning potential. By direct comparison of the calculated efficiencies for different external field and spin current directions, we are able to disentangle the different contributions from the spin transfer torque, Joule heating and the Oersted field. The observed high efficiency of the pure spin current induced spin transfer torque allows for a complete depinning of the domain wall at zero external field for a charge current density of [Formula: see text] A m-2, which is attributed to the optimal control of the position of the domain wall.

15.
Sci Rep ; 5: 8905, 2015 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-25752272

RESUMO

The electric-field (E-field) controlled exchange bias (EB) in a Co90Fe10/BiFeO3 (BFO)/SrRuO3/PMN-PT heterostructure has been investigated under different tensile strain states. The in-plane tensile strain of the BFO film is changed from +0.52% to +0.43% as a result of external E-field applied to the PMN-PT substrate. An obvious change of EB by the control of non-volatile strain has been observed. A magnetization reversal driven by E-field has been observed in the absence of magnetic field. Our results indicate that a reversible non-volatile E-field control of a ferromagnetic layer through strain modulated multiferroic BFO could be achieved at room temperature.

16.
Am J Prev Med ; 13(1): 36-44, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9037340

RESUMO

INTRODUCTION: Proof of effectiveness now exists for many health promotion and disease prevention practices, yet the importance of this knowledge is not widely appreciated, and a large percentage of the population does not receive this care. Universities with comprehensive academic medical centers are particularly appropriate places for providing health promotion programs. The University of Virginia began a health promotion and disease prevention program for employees in 1990. METHODS: Periodic health risk appraisal, with follow-up and selected interventions, is offered to approximately 14,000 employees as a cost-free fringe benefit. Health risks are assessed with a modification of the Carter Center Health Risk Appraisal. Results are given to participants in group sessions; referrals are made for clinical preventive services and interventions, as needed. RESULTS: During the first three years, 29% of the employee population participated in the program. Participants were more likely to be young, female and not African American. Nearly 96% had one or more risk factors, with an average of 3.6 risk factors overall. Participants on average had 1.8 risk factors for cardiovascular disease; 0.3 for cancer; 0.6 for injury; 0.1 for alcohol abuse; and 0.7 for mental health. Nonparticipants were not receiving similar comprehensive health risk appraisal elsewhere. CONCLUSIONS: University of Virginia employees have multiple health risks, not detected through their usual health care, for which effective interventions are available. This population probably reflects conditions throughout the state and nation. Academic medical centers should place high priority on establishing health promotion programs as part of their responsibilities to society.


Assuntos
Promoção da Saúde , Serviços de Saúde do Trabalhador/organização & administração , Serviços Preventivos de Saúde/organização & administração , Universidades , Adolescente , Adulto , Idoso , Eficiência Organizacional , Feminino , Seguimentos , Indicadores Básicos de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Virginia
17.
Clin Nephrol ; 55(4): 331-4, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11334322

RESUMO

Endocarditis is a recognised complication ofhemodialysis. This is generally only thought of in terms of infective vegetations. We present a case of right-sided NBTE in a patient with an indwelling venous catheter who also had advanced pelvic malignancy. The unusual side of this patient's endocarditic lesions implicates a role for the venous catheter in determining the site of non-bacterial thrombus formation. It is also a reminder that endocarditis is always a risk when using central venous catheters, even after appropriate sterile precautions have been taken.


Assuntos
Cateterismo Venoso Central/efeitos adversos , Endocardite/etiologia , Neoplasias Primárias Múltiplas/genética , Neoplasias Pélvicas/complicações , Diálise Renal , Neoplasias das Glândulas Sebáceas/complicações , Trombose/etiologia , Adulto , Cateteres de Demora , Endocardite/diagnóstico , Feminino , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Neoplasias Pélvicas/genética , Neoplasias das Glândulas Sebáceas/genética , Síndrome
18.
Clin Nephrol ; 55(4): 297-302, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11334315

RESUMO

AIMS: To identify any clinical or biochemical parameters which determine prognostic outcome in isolated sarcoid granulomatous interstitial nephritis presenting with renal failure. METHODS: A review of five cases of renal failure due to isolated sarcoid granulomatous interstitial nephritis, which presented to Hope Hospital over the 7-year period 1994 to 2000. Follow-up averaged 35 months with a range of 11 to 73 months. RESULTS: Only one patient had an elevated serum ACE at presentation, reflecting the suboptimal sensitivity of this test as a marker in sarcoidosis and the limited extent of disease in these patients. Four of the five cases had a marked improvement in creatinine clearance within 10 days of starting oral prednisolone. Two patients required acute hemodialysis on presentation. Their renal failure responded to treatment with steroids, enabling withdrawal of dialysis within 10 days. All patients remained dialysis-independent although serum creatinine levels rose during follow-up. One patient experienced a relapse that responded to an increased dose of steroid. CONCLUSIONS: Serum ACE is not reliable in the diagnosis of renal failure due to sarcoid interstitial nephritis and the diagnosis can only be made on renal biopsy. First-line treatment with oral prednisolone results in a rapid improvement in creatinine clearance although prolonged treatment may be needed to prevent a relapse.


Assuntos
Granuloma/diagnóstico , Nefrite Intersticial/diagnóstico , Sarcoidose/diagnóstico , Idoso , Feminino , Glucocorticoides/uso terapêutico , Granuloma/patologia , Granuloma/terapia , Humanos , Rim/patologia , Masculino , Pessoa de Meia-Idade , Nefrite Intersticial/patologia , Nefrite Intersticial/terapia , Prednisolona/uso terapêutico , Prognóstico , Diálise Renal , Insuficiência Renal/etiologia , Insuficiência Renal/terapia , Sarcoidose/patologia , Sarcoidose/terapia
19.
Eur J Radiol ; 12(1): 35-7, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1999207

RESUMO

We have reviewed the radiological studies in 31 patients who underwent stapled colorectal anastomoses using the EEA staple gun. In 10 patients there was clinical evidence to suggest anastomotic dehiscence. Nine of these patients had a disrupted staple ring on plain abdominal radiograph. In these days of audit and financial constraint, we suggest that radiological investigation should be reversed for those patients with questionable clinical evidence of an anastomotic leak.


Assuntos
Colo/diagnóstico por imagem , Grampeadores Cirúrgicos , Deiscência da Ferida Operatória/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Colo/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Reto/diagnóstico por imagem , Reto/cirurgia
20.
Dev Psychol ; 34(5): 882-91, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9779735

RESUMO

The study examined the relationship between children's conceptual understanding and addition problem-solving procedures. Forty-eight 6- to 8-year-olds solved addition problems and, in a 2nd task, were prompted to judge whether a puppet could use the arithmetic properties of one problem to solve the next problem. Relational properties between consecutive problems were manipulated to reflect aspects of additive composition, commutativity, and associativity principles. Conceptual understanding was assessed by the ability to spontaneously use such relational properties in problem solving (Task 1) and to recognize and explain them when prompted (Task 2). Results revealed that conceptual understanding was related to using order-indifferent, decomposition, and retrieval strategies and speed and accuracy in solving unrelated problems. The importance of conceptual understanding for addition development is discussed.


Assuntos
Formação de Conceito , Matemática , Resolução de Problemas , Aprendizagem por Associação , Criança , Feminino , Humanos , Masculino , Rememoração Mental
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