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1.
Nat Med ; 29(1): 190-202, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36646800

RESUMO

Primary aldosteronism (PA) due to a unilateral aldosterone-producing adenoma is a common cause of hypertension. This can be cured, or greatly improved, by adrenal surgery. However, the invasive nature of the standard pre-surgical investigation contributes to fewer than 1% of patients with PA being offered the chance of a cure. The primary objective of our prospective study of 143 patients with PA ( NCT02945904 ) was to compare the accuracy of a non-invasive test, [11C]metomidate positron emission tomography computed tomography (MTO) scanning, with adrenal vein sampling (AVS) in predicting the biochemical remission of PA and the resolution of hypertension after surgery. A total of 128 patients reached 6- to 9-month follow-up, with 78 (61%) treated surgically and 50 (39%) managed medically. Of the 78 patients receiving surgery, 77 achieved one or more PA surgical outcome criterion for success. The accuracies of MTO at predicting biochemical and clinical success following adrenalectomy were, respectively, 72.7 and 65.4%. For AVS, the accuracies were 63.6 and 61.5%. MTO was not significantly superior, but the differences of 9.1% (95% confidence interval = -6.5 to 24.1%) and 3.8% (95% confidence interval = -11.9 to 9.4) lay within the pre-specified -17% margin for non-inferiority (P = 0.00055 and P = 0.0077, respectively). Of 24 serious adverse events, none was considered related to either investigation and 22 were fully resolved. MTO enables non-invasive diagnosis of unilateral PA.


Assuntos
Hiperaldosteronismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Glândulas Suprarrenais/diagnóstico por imagem , Glândulas Suprarrenais/cirurgia , Glândulas Suprarrenais/irrigação sanguínea , Hiperaldosteronismo/diagnóstico por imagem , Hiperaldosteronismo/cirurgia , Estudos Prospectivos , Estudos Retrospectivos
2.
Surg Oncol ; 45: 101875, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36384070

RESUMO

BACKGROUND: Surgery for perihilar cholangiocarcinoma (pCCA) offers the only possibility of long-term survival, but remains a formidable undertaking. Traditionally, 90-day post-operative complications and death are used to define operative risk. However, there is concern that this metric may not accurately capture long-term morbidity after such complex surgery. METHODS: A retrospective review of a prospective database of patients undergoing surgery for pCCA at a Western centre between January 2009-2020. RESULTS: Eighty-five patients underwent surgical resection for pCCA with a median overall survival of 36.3 months. Post-op (<90day) morbidity rates were high with 46% of patients developing a major complication (Clavien-Dindo grade 3-4). Post-op mortality rate was 13%. In total 38% (28/74) of patients experienced at least 1 episode of delayed morbidity (>90-days of surgery) resulting in 53 separate admissions with a median LOS of 7 days (IQR 2-15). These episodes were predominately secondary to biliary obstruction with the majority requiring radiological intervention (Clavien-Dindo grade 3). The development of long-term morbidity was associated with increased recurrence rates and correlated with poorer OS (27.6 months vs. 65.7 months HR 2.2 CI 1.63-2.77). CONCLUSIONS: Routinely cited 90-day morbidity and mortality does not accurately capture the patient morbidity experienced following surgery for pCCA. Surgery clearly offers a survival benefit and should be pursued in selected patients, but they must be fully counselled on the potential for long-term morbidity before embarking on this strategy.


Assuntos
Neoplasias dos Ductos Biliares , Colestase , Tumor de Klatskin , Humanos , Tumor de Klatskin/cirurgia , Estudos de Coortes , Morbidade , Neoplasias dos Ductos Biliares/cirurgia
3.
Development ; 149(18)2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35993314

RESUMO

In the absence of pollination, female reproductive organs senesce, leading to an irrevocable loss in the reproductive potential of the flower, which directly affects seed set. In self-pollinating crops like wheat (Triticum aestivum), the post-anthesis viability of unpollinated carpels has been overlooked, despite its importance for hybrid seed production systems. To advance our knowledge of carpel development in the absence of pollination, we created a high-throughput phenotyping approach to quantify stigma and ovary morphology. We demonstrate the suitability of the approach, which uses light-microscopy imaging and machine learning, for the analysis of floral organ traits in field-grown plants using fresh and fixed samples. We show that the unpollinated carpel undergoes a well-defined initial growth phase, followed by a peak phase in which stigma area reaches its maximum and the radial expansion of the ovary slows, and a final deterioration phase. These developmental dynamics were consistent across years and could be used to classify male-sterile cultivars. This phenotyping approach provides a new tool for examining carpel development, which we hope will advance research into female fertility of wheat.


Assuntos
Polinização , Triticum , Produtos Agrícolas , Flores/anatomia & histologia , Flores/genética , Sementes/genética , Triticum/genética
4.
Pediatr Blood Cancer ; 69(8): e29663, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35373890

RESUMO

High-dose chemotherapy with autologous stem cell transplant (ASCT) has been a mainstay of high-risk neuroblastoma treatment for several decades, demonstrating improvements in event-free survival but with risks of serious or even life-threatening acute toxicities, severe long-term adverse health effects for survivors, and ongoing contention regarding overall survival benefit. The merits of ASCT in the modern era of immunotherapy are a source of debate among parents, advocates, and some physicians. Here we examine evidence for and against ASCT, explore parent attitudes and their turmoil over decision-making, and strongly encourage international research consortia to develop a coordinated strategy to accelerate progress toward a future that avoids the routine use of ASCT in high-risk neuroblastoma.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Neuroblastoma , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Intervalo Livre de Doença , Humanos , Imunoterapia , Defesa do Paciente , Transplante Autólogo
5.
J Surg Oncol ; 125(3): 399-404, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34689332

RESUMO

BACKGROUND: Preoperative diagnosis for suspected gallbladder cancers is challenging, with a risk of overtreating benign disease, for example, xanthogranulomatous cholecystitis, with radical cholecystectomies. We retrospectively evaluated the surgeon's intraoperative assessment alone, and with the addition of intraoperative frozen sections, for suspected gallbladder cancers from a tertiary hepatobiliary multidisciplinary team (MDT). METHODS: MDT patients with complex gallbladder disease were included. Collated data included demographics, MDT discussion, operative details, and patient outcomes. RESULTS: A total of 454 patients with complex gallbladder disease were reviewed, 48 (10.6%) were offered radical surgery for suspected cancer. Twenty-five underwent frozen section that led to radical surgery in 6 (25%). All frozen sections were congruent with final histopathology but doubled the operating time (p < 0.0001). Both the surgeon's subjective and additional frozen section's objective assessment, allowed for de-escalation of unnecessary radical surgery, comparing favourably to a 13.0% cancer diagnosis among radical surgery historically. CONCLUSIONS: The MDT process was highly sensitive in identifying gallbladder cancers but lacked specificity. The surgeon's intraoperative assessment is paramount in suspected cancers, and deescalated unnecessary radical surgery. Intraoperative frozen section was a safe and viable adjunct at a cost of resources and operative time.


Assuntos
Carcinoma/patologia , Carcinoma/cirurgia , Colecistectomia , Secções Congeladas , Neoplasias da Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/cirurgia , Idoso , Carcinoma/mortalidade , Feminino , Neoplasias da Vesícula Biliar/mortalidade , Humanos , Linfoma/mortalidade , Linfoma/patologia , Linfoma/cirurgia , Masculino , Melanoma/mortalidade , Melanoma/patologia , Melanoma/cirurgia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Duração da Cirurgia , Estudos Retrospectivos , Sensibilidade e Especificidade , Taxa de Sobrevida
6.
Br J Clin Pharmacol ; 88(2): 702-712, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34292606

RESUMO

AIMS: GSK3511294 is a humanized anti-interleukin (IL)-5 monoclonal antibody (mAb) engineered for extended half-life and improved IL-5 affinity versus other anti-IL-5 mAbs. This study examined its safety, tolerability, pharmacokinetics (PK) and effect on blood eosinophil counts. METHODS: This was a double-blind, parallel-group, single-ascending-dose, multicenter, Phase 1 study (205 722;NCT03287310) in patients with asthma and a blood eosinophil count ≥200 cells µL-1 . Patients were randomized 3:1 within dose cohorts to receive a single subcutaneous dose of GSK3511294 (2, 10, 30, 100 or 300 mg) or placebo and followed for up to 40 weeks to assess safety (primary endpoint), ratio to baseline in blood eosinophil count, plasma PK parameters and frequency/titers of binding antidrug antibodies (all secondary). RESULTS: Forty-eight patients received the study drug and completed the study. Adverse events (AEs) occurred in 92% of placebo-treated and 81% of GSK3511294-treated patients. There were no AEs leading to study withdrawal or serious AEs; hypersensitivity (one event in one patient) and injection-site reaction (three events in two patients) occurred infrequently. Marked reductions (>48%) in blood eosinophil count were seen from 24 hours post-dose with all GSK3511294 doses but not placebo; suppression was maintained for longer with increasing dose (82% and 83% adjusted reductions vs placebo with 100 and 300 mg, respectively, at week 26). PK were linear and dose proportional over the dose range; terminal half-life was 38-53 days. CONCLUSIONS: GSK3511294 was well tolerated, with linear and dose proportional PK, extended half-life and blood eosinophil count reduction, supporting less frequent dosing versus other anti-IL-5 mAbs.


Assuntos
Asma , Interleucina-5 , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Asma/complicações , Asma/terapia , Método Duplo-Cego , Eosinófilos/metabolismo , Humanos , Interleucina-5/antagonistas & inibidores , Interleucina-5/metabolismo , Interleucina-5/uso terapêutico
8.
Nucl Med Commun ; 42(1): 58-62, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33044401

RESUMO

AIMS: First, to derive gender-specific formulae for estimation of extracellular fluid volume (eECV) and second, compare eECV as a scaling metric for slope-intercept glomerular filtration rate (GFR) with estimated body surface area (eBSA), lean body mass (eLBM) and total body water (eTBW). METHODS: GFR and 'slope-only' GFR (GFR/ECV), both single compartment-corrected, were measured in a previously published multicentre database of healthy potential kidney transplant donors. Measured ECV (mECV) was obtained as ratio GFR-to-GFR/ECV. Formulae for eECV in men and women were derived from the relationship of mECV with height and weight and expressed as eECV = a.weight.height. In a population of prospective kidney transplant donors from a single centre, eECV was compared with mECV. GFR was scaled to eECV, eBSA, eLBM and eTBW, estimated from previously published formulae. RESULTS: In men and women, respectively, a was 0.0755 and 0.0399, x was 0.6185 and 0.6065 and y was 0.4982 and 0.6217. In the single centre, biases (±precisions) of eECV against mECV in men and women were 0.26 (±1.68) and 0.31 (±1.67) l. Mean GFR/eBSA was higher in men but mean GFR/eLBM and GFR/eTBW were higher in women. Mean GFR/ECV and mean GFR/eECV were very similar between the two genders. GFR/ECV and GFR/eECV showed correlations with each other that were almost identical between men and women. CONCLUSIONS: New formulae are described for estimating eECV. Scaling GFR to eECV is more physiological than scaling to eBSA and accounts for gender. eECV used for measuring GFR from a single blood sample should be gender-specific.


Assuntos
Estatura , Peso Corporal , Líquido Extracelular/metabolismo , Testes de Função Renal/métodos , Caracteres Sexuais , Adulto , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade
9.
Clin Cancer Res ; 27(5): 1381-1390, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33303580

RESUMO

PURPOSE: Management of patients with cancer, specifically carboplatin dosing, requires accurate knowledge of glomerular filtration rate (GFR). Direct measurement of GFR is resource limited. Available models for estimated GFR (eGFR) are optimized for patients without cancer and either isotope dilution mass spectrometry (IDMS)- or non-IDMS-standardized creatinine measurements. We present an eGFR model for patients with cancer compatible with both creatinine measurement methods. EXPERIMENTAL DESIGN: GFR measurements, biometrics, and IDMS- or non-IDMS-standardized creatinine values were collected for adult patients from three cancer centers. Using statistical modeling, an IDMS and non-IDMS creatinine-compatible eGFR model (CamGFR v2) was developed. Its performance was compared with that of the existing models Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), Modification of Diet in Renal Disease (MDRD), Full Age Spectrum (FAS), Lund-Malmö revised, and CamGFR v1, using statistics for bias, precision, accuracy, and clinical robustness. RESULTS: A total of 3,083 IDMS- and 4,612 non-IDMS-standardized creatinine measurements were obtained from 7,240 patients. IDMS-standardized creatinine values were lower than non-IDMS-standardized values in within-center comparisons (13.8% lower in Cambridge; P < 0.0001 and 19.3% lower in Manchester; P < 0.0001), and more consistent between centers. CamGFR v2 was the most accurate [root-mean-squared error for IDMS, 14.97 mL/minute (95% confidence interval, 13.84-16.13) and non-IDMS, 15.74 mL/minute (14.86-16.63)], most clinically robust [proportion with >20% error of calculated carboplatin dose for IDMS, 0.12 (0.09-0.14) and non-IDMS, 0.17 (0.15-0.2)], and least biased [median residual for IDMS, 0.73 mL/minute (-0.68 to 2.2) and non-IDMS, -0.43 mL/minute (-1.48 to 0.91)] eGFR model, particularly when eGFR was larger than 60 ml/minute. CONCLUSIONS: CamGFR v2 can utilize IDMS- and non-IDMS-standardized creatinine measurements and outperforms previous models. CamGFR v2 should be examined prospectively as a practice-changing standard of care for eGFR-based carboplatin dosing.


Assuntos
Creatinina/sangue , Creatinina/normas , Taxa de Filtração Glomerular , Modelos Estatísticos , Neoplasias/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/patologia , Prognóstico
10.
JNCI Cancer Spectr ; 3(4): pkz068, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31750418

RESUMO

Important oncological management decisions rely on kidney function assessed by serum creatinine-based estimated glomerular filtration rate (eGFR). However, no large-scale multicenter comparisons of methods to determine eGFR in patients with cancer are available. To compare the performance of formulas for eGFR based on routine clinical parameters and serum creatinine not calibrated with isotope dilution mass spectrometry, we studied 3620 patients with cancer and 166 without cancer who had their glomerular filtration rate (GFR) measured with an exogenous nuclear tracer at one of seven clinical centers. The mean measured GFR was 86 mL/min. Accuracy of all models was center dependent, reflecting intercenter variability of isotope dilution mass spectrometry-creatinine measurements. CamGFR was the most accurate model for eGFR (root-mean-squared error 17.3 mL/min) followed by the Chronic Kidney Disease Epidemiology Collaboration model (root-mean-squared error 18.2 mL/min).

11.
HPB (Oxford) ; 21(10): 1376-1384, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31078423

RESUMO

BACKGROUND: Several prognostic systems have been proposed to guide management strategies post-resection for patients with hilar cholangiocarcinoma. The objective of this study was to evaluate the efficacy of these conventional prognostic models, with respect to Overall Survival (OS), on patients in a modern single-centre resectional cohort. METHOD: Patients diagnosed with hilar cholangiocarcinoma, referred to a supra-regional tertiary referral centre between February 2009 and February 2016, were retrospectively analysed from a prospectively held database linked to Hospital Episode Statistics and Somerset Cancer Registry data. RESULTS: Two-hundred and one patients were assessed for suitability for surgery. Eighty-three (41%) patients considered to have potentially resectable disease underwent surgical assessment of resectability. Fifty-six (68%) patients proceeded to resection. Multivariate analysis demonstrated that pre-operative Serum CA 19-9 (p = 0.007), Radiological Arterial Involvement (p = 0.005) and Amsterdam Medical Centre (AMC) prognostic model score (p = 0.032) retained significance in association with OS. Multivariate models developed from this cohort out-performed the conventional prognostic systems for OS. CONCLUSION: The cohort-derived multivariate models demonstrated significantly improved prognostic capability compared to conventional systems in explaining OS.


Assuntos
Tumor de Klatskin/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Biópsia , Feminino , Seguimentos , Humanos , Tumor de Klatskin/mortalidade , Tumor de Klatskin/cirurgia , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Reino Unido/epidemiologia
12.
Eur J Trauma Emerg Surg ; 45(2): 231-243, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30008075

RESUMO

PURPOSE: Emergency department thoracotomy (EDT) is a potentially life-saving procedure, performed on patients suffering traumatic cardiac arrest. Multiple indications have been reported, but overall survival remains unclear for each indication. The objective of this systematic review is to determine overall survival, survival stratified by indication, and survival stratified by geographical location for patients undergoing EDT across the world. METHODS: Articles published between 2000 and 2016 were identified which detailed outcomes from EDT. All articles referring to pre-hospital, delayed, or operating room thoracotomy were excluded. Pooled odds ratios (OR) were calculated comparing differing indications. RESULTS: Thirty-seven articles, containing 3251 patients who underwent EDT, were identified. There were 277 (8.5%) survivors. OR demonstrate improved survival for; penetrating vs blunt trauma (OR 2.10; p 0.0028); stab vs gun-shot (OR 5.45; p < 0.0001); signs of life (SOL) on admission vs no SOL (OR 5.36; p < 0.0001); and SOL in the field vs no SOL (OR 19.39; p < 0.0001). Equivalence of survival was demonstrated between cardiothoracic vs non-cardiothoracic injury (OR 1.038; p 1.000). Survival was worse for USA vs non-USA cohorts (OR 1.59; p 0.0012). CONCLUSIONS: Penetrating injury remains a robust indication for EDT. Non-cardiothoracic cause of cardiac arrest should not preclude EDT. In the absence of on scene SOL, survival following EDT is extremely unlikely. Survival is significantly higher in the non-USA publications; reasons for this are highly complex. A UK multicentre prospective study which collects standardised data on all EDTs could provide robust evidence for better patient stratification.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Parada Cardíaca/cirurgia , Traumatismos Torácicos/cirurgia , Toracotomia/estatística & dados numéricos , Sistemas de Gerenciamento de Base de Dados , Parada Cardíaca/etiologia , Parada Cardíaca/fisiopatologia , Humanos , Traumatismos Torácicos/complicações , Traumatismos Torácicos/fisiopatologia , Resultado do Tratamento
13.
Eur J Surg Oncol ; 45(2): 192-197, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30297275

RESUMO

AIMS: Cholangiocarcinoma is a rare cancer arising from the biliary tree. Case series indicate that 25-40% of all borderline resectable primary tumours are potentially resectable. The Memorial Sloane Kettering System (MSKCC) stratifies patients for resectability by longitudinal and radial extension of the hilar tumour. The Bismuth-Corlette system describes the longitudinal extension of the tumour within the biliary duct system. We sought to validate and, if possible, augment these two scores within an independent validation cohort. METHODS: Patients diagnosed with hilar cholangiocarcinoma between January 2009 and December 2016 were analysed from a prospectively held database. Patients with distal cholangiocarcinoma, peripheral cholangiocarcinoma and gallbladder cancer were excluded. Comparison of surgical findings to pre-operative radiological imaging was undertaken at the time of surgery. RESULTS: The validation cohort was formed of 198 patients, of which, 55 (27.8%) patients underwent resection. Logistic regression analyses identified that BC score, MSKCC score, age at diagnosis and left artery involvement were all significant independent predictor's univariately. BC score explained 28% of the variability in resectability compared to 26% explained by MSKCC. In combination, the model consisting of BC score, age at diagnosis and left artery involvement explained 39% of variability in resectability compared to the 34% explained same model including MSKCC score instead of BC score. CONCLUSION: In this cohort an augmented BC score, incorporating left hepatic artery involvement, is more discriminative in predicting resectability than the current MSKCC system.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/cirurgia , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/cirurgia , Cuidados Pré-Operatórios , Tomografia Computadorizada por Raios X , Idoso , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Colangiocarcinoma/patologia , Feminino , Artéria Hepática/diagnóstico por imagem , Artéria Hepática/patologia , Artéria Hepática/cirurgia , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Resultado do Tratamento
14.
Eur J Trauma Emerg Surg ; 44(6): 811-818, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29564472

RESUMO

PURPOSE: The indications for pre-hospital resuscitative thoracotomy (PHRT) remain undefined. The aim of this paper is to explore the variation in practice for PHRT in the UK, and review the published literature. METHODS: MEDLINE and PUBMED search engines were used to identify all relevant articles and 22 UK Air Ambulance Services were sent an electronic questionnaire to assess their PHRT practice. RESULTS: Four European publications report PHRT survival rates of 9.7, 18.3, 10.3 and 3.0% in 31, 71, 39 and 33 patients, respectively. All patients sustained penetrating chest injury. Six case reports also detail survivors of PHRT, again all had sustained penetrating thoracic injury. One Japanese paper presents 34 cases of PHRT following blunt trauma, of which 26.4% survived to the intensive therapy unit but none survived to discharge. A UK population reports a single survivor of PHRT following blunt trauma but the case details remain unpublished. Ten (45%) air ambulance services responded, each service reported different indications for PHRT. All perform PHRT for penetrating chest trauma, however, length of allowed pre-procedure down time varied, ranging from 10 to 20 min. Seventy percent perform PHRT for blunt traumatic cardiac arrest, a procedure which is likely to require aggressive concurrent circulatory support, despite this only 5/10 services carry pre-hospital blood products. CONCLUSIONS: Current indications for PHRT vary amongst different geographical locations, across the UK, and worldwide. Survivors are likely to have sustained penetrating chest injury with short down time. There is only one published survivor of PHRT following blunt trauma, despite this, PHRT is still being performed in the UK for this indication.


Assuntos
Ressuscitação , Traumatismos Torácicos/terapia , Toracotomia/métodos , Ferimentos Penetrantes/terapia , Serviços Médicos de Emergência , Humanos , Taxa de Sobrevida , Traumatismos Torácicos/mortalidade , Ferimentos Penetrantes/mortalidade
15.
Nucl Med Commun ; 38(6): 471-479, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28394818

RESUMO

OBJECTIVE: The objective of this study was to quantify any improvement with the GE 'Sharp IR' point-spread function (PSF) reconstruction algorithm in addition to ordered subsets expectation maximum (OSEM) and time-of-flight (TOF) reconstruction algorithms and establish the optimum parameters to be used in clinical studies. MATERIALS AND METHODS: We conducted a range of experiments using the National Electrical Manufacturers Association image quality phantom filled with a 4 : 1 signal-to-background ratio. We scanned the phantom using the GE Discovery 690 PET/CT scanner. We varied iteration number and Gaussian filtration. Results were compared for OSEM, OSEM+TOF and OSEM+TOF+PSF reconstructions. A sample of 15 whole-body fluorine-18-fluorodeoxyglucose were reconstructed with OSEM+TOF and OSEM+TOF+PSF using a selection of optimum reconstruction parameters determined in phantom studies. Clinicians qualitatively ranked their preferred images to choose optimum parameters. RESULTS: The addition of PSF improved signal-to-noise ratios (SNRs), contrast, hot contrast recovery coefficients and noise over OSEM and OSEM+TOF reconstruction algorithms. SNRs were the highest at two iterations and with 0 or 2 mm filters with OSEM+TOF+PSF reconstruction in all phantom studies. Clinicians generally favoured OSEM+TOF+PSF reconstruction with three iterations and a 2 mm filter. CONCLUSION: PSF reconstruction significantly improved image quality for both clinical and phantom studies. We recommended the optimum reconstruction parameters using three iterations, 24 subsets and a 2 mm filter, which improved SNRs by up to 28.8% for small lesions (P<0.05).


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Controle de Qualidade
16.
J Exp Bot ; 67(14): 4169-78, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27217549

RESUMO

The precocious germination of cereal grains before harvest, also known as pre-harvest sprouting, is an important source of yield and quality loss in cereal production. Pre-harvest sprouting is a complex grain defect and is becoming an increasing challenge due to changing climate patterns. Resistance to sprouting is multi-genic, although a significant proportion of the sprouting variation in modern wheat cultivars is controlled by a few major quantitative trait loci, including Phs-A1 in chromosome arm 4AL. Despite its importance, little is known about the physiological basis and the gene(s) underlying this important locus. In this study, we characterized Phs-A1 and show that it confers resistance to sprouting damage by affecting the rate of dormancy loss during dry seed after-ripening. We show Phs-A1 to be effective even when seeds develop at low temperature (13 °C). Comparative analysis of syntenic Phs-A1 intervals in wheat and Brachypodium uncovered ten orthologous genes, including the Plasma Membrane 19 genes (PM19-A1 and PM19-A2) previously proposed as the main candidates for this locus. However, high-resolution fine-mapping in two bi-parental UK mapping populations delimited Phs-A1 to an interval 0.3 cM distal to the PM19 genes. This study suggests the possibility that more than one causal gene underlies this major pre-harvest sprouting locus. The information and resources reported in this study will help test this hypothesis across a wider set of germplasm and will be of importance for breeding more sprouting resilient wheat varieties.


Assuntos
Germinação/fisiologia , Dormência de Plantas/fisiologia , Locos de Características Quantitativas/genética , Triticum/crescimento & desenvolvimento , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Cromossomos de Plantas/fisiologia , Genes de Plantas/genética , Genes de Plantas/fisiologia , Técnicas de Genotipagem , Germinação/genética , Dormência de Plantas/genética , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/fisiologia , Triticum/genética
17.
PLoS One ; 10(9): e0137549, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26335335

RESUMO

Targeted Induced Local Lesions in Genomes (TILLING) is a reverse genetics approach to identify novel sequence variation in genomes, with the aims of investigating gene function and/or developing useful alleles for breeding. Despite recent advances in wheat genomics, most current TILLING methods are low to medium in throughput, being based on PCR amplification of the target genes. We performed a pilot-scale evaluation of TILLING in wheat by next-generation sequencing through exon capture. An oligonucleotide-based enrichment array covering ~2 Mbp of wheat coding sequence was used to carry out exon capture and sequencing on three mutagenised lines of wheat containing previously-identified mutations in the TaGA20ox1 homoeologous genes. After testing different mapping algorithms and settings, candidate SNPs were identified by mapping to the IWGSC wheat Chromosome Survey Sequences. Where sequence data for all three homoeologues were found in the reference, mutant calls were unambiguous; however, where the reference lacked one or two of the homoeologues, captured reads from these genes were mis-mapped to other homoeologues, resulting either in dilution of the variant allele frequency or assignment of mutations to the wrong homoeologue. Competitive PCR assays were used to validate the putative SNPs and estimate cut-off levels for SNP filtering. At least 464 high-confidence SNPs were detected across the three mutagenized lines, including the three known alleles in TaGA20ox1, indicating a mutation rate of ~35 SNPs per Mb, similar to that estimated by PCR-based TILLING. This demonstrates the feasibility of using exon capture for genome re-sequencing as a method of mutation detection in polyploid wheat, but accurate mutation calling will require an improved genomic reference with more comprehensive coverage of homoeologues.


Assuntos
DNA de Plantas , Éxons , Mutação , Triticum/genética , Alelos , Análise Mutacional de DNA , Genoma de Planta , Sequenciamento de Nucleotídeos em Larga Escala , Fenótipo , Poliploidia
18.
Biomark Med ; 9(8): 763-75, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26223884

RESUMO

UNLABELLED: Better prognostic information for resected extrahepatic cholangiocarcinoma could guide treatment strategies and potentially improve outcome. This study performed a systematic review and meta-analysis to identify prognostic biomarkers for further investigation. METHODS: Relevant literature was identified using Medline, EMBASE and Web of Science. Primary end point was overall survival assessed on univariate analysis. Log hazard ratio and variance were calculated and pooled using a random effects inverse variance approach. Hazard ratio and 95% confidence intervals were calculated. RESULTS: Thirty-seven studies, including 2371 patients, met the inclusion criteria. Subsequently nine biomarkers predictive of OS were identified (HR, 95% CI): VEGF (2.32, 1.57-3.44), COX-2 (1.94, 1.01-3.71), GLUT-1 (2.09, 1.52-2.89), Cyclin D1 (1.96, 1.02-3.76), p16 (0.68, 0.47-0.98), p27 (0.48, 0.3-0.78), E-Cadherin (0.47, 0.35-0.63), Fascin (2.19, 1.35-3.55), and Ki-67 (1.69, 1.02-2.79). CONCLUSION: Meta-analysis has identified a number of prognostic biomarkers for resected extrahepatic cholangiocarcinoma. These markers warrant further investigation as potential therapeutic targets and validation in a prospective setting.


Assuntos
Ductos Biliares Extra-Hepáticos/metabolismo , Neoplasias do Sistema Biliar/metabolismo , Biomarcadores Tumorais/análise , Imuno-Histoquímica/métodos , Ductos Biliares Extra-Hepáticos/patologia , Neoplasias do Sistema Biliar/diagnóstico , Humanos , Imuno-Histoquímica/estatística & dados numéricos , Prognóstico , Modelos de Riscos Proporcionais , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise de Sobrevida
19.
Plant Biotechnol J ; 13(5): 613-24, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25382230

RESUMO

The identification of genetic markers linked to genes of agronomic importance is a major aim of crop research and breeding programmes. Here, we identify markers for Yr15, a major disease resistance gene for wheat yellow rust, using a segregating F2 population. After phenotyping, we implemented RNA sequencing (RNA-Seq) of bulked pools to identify single-nucleotide polymorphisms (SNP) associated with Yr15. Over 27 000 genes with SNPs were identified between the parents, and then classified based on the results from the sequenced bulks. We calculated the bulk frequency ratio (BFR) of SNPs between resistant and susceptible bulks, selecting those showing sixfold enrichment/depletion in the corresponding bulks (BFR > 6). Using additional filtering criteria, we reduced the number of genes with a putative SNP to 175. The 35 SNPs with the highest BFR values were converted into genome-specific KASP assays using an automated bioinformatics pipeline (PolyMarker) which circumvents the limitations associated with the polyploid wheat genome. Twenty-eight assays were polymorphic of which 22 (63%) mapped in the same linkage group as Yr15. Using these markers, we mapped Yr15 to a 0.77-cM interval. The three most closely linked SNPs were tested across varieties and breeding lines representing UK elite germplasm. Two flanking markers were diagnostic in over 99% of lines tested, thus providing a reliable haplotype for marker-assisted selection in these breeding programmes. Our results demonstrate that the proposed methodology can be applied in polyploid F2 populations to generate high-resolution genetic maps across target intervals.


Assuntos
Basidiomycota/fisiologia , Doenças das Plantas/imunologia , Polimorfismo de Nucleotídeo Único/genética , Triticum/genética , Sequência de Bases , Cruzamento , Mapeamento Cromossômico , Resistência à Doença , Ligação Genética , Marcadores Genéticos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Poliploidia , RNA de Plantas/química , RNA de Plantas/genética , Análise de Sequência de RNA , Triticum/imunologia
20.
Diving Hyperb Med ; 44(2): 79-85, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24986725

RESUMO

BACKGROUND: Scuba diving injuries vary greatly in severity and prognosis. While decompression sickness (DCS) and arterial gas embolism can be tracked easily, other forms of diving injury remain unaccounted for. PURPOSE: The purpose of this paper is to assess rates of overall self-reported scuba-diving-related injuries, self-reported DCS-like symptoms, and treated DCS and their association with diver certification level, diving experience and demographic factors. METHODS: We analyzed self-reported data from a Divers Alert Network membership health survey conducted during the summer of 2011. Poisson regression models with scaled deviance were used to model the relative rates of reported injuries. Models were adjusted for sex, age, body mass index (BMI) and average annual dives, based on the bias-variance tradeoff. RESULTS: The overall rate of diving-related injury was 3.02 per 100 dives, self-reported DCS symptoms was 1.55 per 1,000 dives and treated DCS was 5.72 per 100,000 dives. Diving-related injury and self-reported DCS symptom rates decreased for higher diver certification levels, increasing age, increasing number of average annual dives and for men; they increased for increasing BMI. CONCLUSIONS: Diving injury rates may be higher than previously thought, indicating a greater burden on the diving community. Self-reported DCS-like symptoms are a small fraction of all dive-related injuries and those receiving treatment for DCS are an even smaller fraction. The small number of divers seeking treatment may suggest the mild nature and a tendency towards natural resolution for most injuries.


Assuntos
Doença da Descompressão/epidemiologia , Mergulho/lesões , Embolia Aérea/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Certificação , Redes Comunitárias/estatística & dados numéricos , Doença da Descompressão/terapia , Mergulho/efeitos adversos , Mergulho/normas , Mergulho/estatística & dados numéricos , Feminino , Inquéritos Epidemiológicos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Distribuição de Poisson , Recreação , Estudos Retrospectivos , Autorrelato , Fatores Sexuais , Adulto Jovem
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