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2.
Rev Sci Instrum ; 94(5)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37191465

RESUMO

Control noise is a limiting factor in the low-frequency performance of the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO). In this paper, we model the effects of using new sensors called Homodyne Quadrature Interferometers (HoQIs) to control the suspension resonances. We show that if we were to use HoQIs, instead of the standard shadow sensors, we could suppress resonance peaks up to tenfold more while simultaneously reducing the noise injected by the damping system. Through a cascade of effects, this will reduce the resonant cross-coupling of the suspensions, allow for improved stability for feed-forward control, and result in improved sensitivity of the detectors in the 10-20 Hz band. This analysis shows that improved local sensors, such as HoQIs, should be used in current and future detectors to improve low-frequency performance.

3.
Phys Eng Sci Med ; 46(2): 851-863, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37126152

RESUMO

Non-small cell lung cancer (NSCLC) patients with the metastatic spread of disease to the bone have high morbidity and mortality. Stereotactic ablative body radiotherapy increases the progression free survival and overall survival of these patients with oligometastases. FDG-PET/CT, a functional imaging technique combining positron emission tomography (PET) with 18 F-fluorodeoxyglucose (FDG) and computer tomography (CT) provides improved staging and identification of treatment response. It is also associated with reduction in size of the radiotherapy tumour volume delineation compared with CT based contouring in radiotherapy, thus allowing for dose escalation to the target volume with lower doses to the surrounding organs at risk. FDG-PET/CT is increasingly being used for the clinical management of NSCLC patients undergoing radiotherapy and has shown high sensitivity and specificity for the detection of bone metastases in these patients. Here, we present a software tool for detection, delineation and quantification of bone metastases using FDG-PET/CT images. The tool extracts standardised uptake values (SUV) from FDG-PET images for auto-segmentation of bone lesions and calculates volume of each lesion and associated mean and maximum SUV. The tool also allows automatic statistical validation of the auto-segmented bone lesions against the manual contours of a radiation oncologist. A retrospective review of FDG-PET/CT scans of more than 30 candidate NSCLC patients was performed and nine patients with one or more metastatic bone lesions were selected for the present study. The SUV threshold prediction model was designed by splitting the cohort of patients into a subset of 'development' and 'validation' cohorts. The development cohort yielded an optimum SUV threshold of 3.0 for automatic detection of bone metastases using FDG-PET/CT images. The validity of the derived optimum SUV threshold on the validation cohort demonstrated that auto-segmented and manually contoured bone lesions showed strong concordance for volume of bone lesion (r = 0.993) and number of detected lesions (r = 0.996). The tool has various applications in radiotherapy, including but not limited to studies determining optimum SUV threshold for accurate and standardised delineation of bone lesions and in scientific studies utilising large patient populations for instance for investigation of the number of metastatic lesions that can be treated safety with an ablative dose of radiotherapy without exceeding the normal tissue toxicity.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Tomografia Computadorizada por Raios X/métodos , Tomografia por Emissão de Pósitrons/métodos , Computadores
4.
Clin Oncol (R Coll Radiol) ; 34(9): 561-570, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35738953

RESUMO

AIMS: To evaluate diffusion-weighted imaging and dynamic contrast-enhanced magnetic resonance imaging for the prediction of disease-free survival (DFS) in patients with locally advanced rectal cancer. MATERIALS AND METHODS: Patients with stage II or III rectal adenocarcinoma undergoing neoadjuvant chemoradiotherapy (CRT) and surgery were eligible. Patients underwent multi-parametric magnetic resonance imaging (diffusion-weighted imaging and dynamic contrast-enhanced) before CRT, during CRT (week 3) and after CRT (1 week prior to surgery). Whole tumour apparent diffusion coefficient (ADC) and Ktrans histogram quantiles (10th, 25th, 50th, 75th, 90th) were extracted for analysis. The associations between ADC and Ktrans at three timepoints with time to relapse were analysed as a continuous variable using a Cox proportional hazard model. RESULTS: Thirty-three patients were included in this analysis. The median follow-up was 4.4 years. No patient had locoregional relapse. Nine patients developed distant metastases. The hazard ratios for after CRT Ktrans 10th (P = 0.035), 25th (P = 0.048), 50th (P = 0.046) and 75th (P = 0.045) quantiles were statistically significant for DFS. The best Ktrans cut-off point after CRT for predicting relapse was 28 × 10-3 mL/g/min (10th quantile), with a higher Ktrans value predicting distant relapse. The 4-year DFS probability was 0.93 for patients with after CRT Ktrans value ≤28 × 10-3 mL/g/min versus 0.45 for patients with after CRT Ktrans value >28 × 10-3 mL/g/min. ADC was not able to predict DFS. CONCLUSIONS: Patients with higher Ktrans values after CRT (before surgery) in a histogram analysis of whole tumour heterogeneity had a significantly lower 4-year distant DFS and could be considered for more intense systemic therapy.


Assuntos
Quimiorradioterapia , Neoplasias Retais , Quimiorradioterapia/métodos , Intervalo Livre de Doença , Humanos , Imageamento por Ressonância Magnética/métodos , Terapia Neoadjuvante , Recidiva Local de Neoplasia/diagnóstico por imagem , Perfusão , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Estudos Retrospectivos , Resultado do Tratamento
5.
Clin Oncol (R Coll Radiol) ; 33(10): 650-660, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33750600

RESUMO

AIMS: Radiotherapy can provide quality of life and/or survival benefits to patients with metastatic cancer on diagnosis (MCOD). However, little is known about radiotherapy utilisation in this population. We compared the optimal radiotherapy rates with actual uptake for people who present with MCOD in the 45 and Up Study cohort, and examined factors associated with utilisation. MATERIALS AND METHODS: In total, 267 153 individuals aged ≥45 enrolled in the Sax Institute's 45 and Up Study completed a baseline questionnaire during 2006-2009, providing sociodemographic and health information and consent for linkage to administrative health databases. Participants diagnosed up to December 2013 with MCOD were identified in the New South Wales Cancer Registry. Radiotherapy receipt was determined from claims to the Medicare Benefits Schedule and/or records in the New South Wales Admitted Patient Data Collection (2006 to June 2016). The Collaboration for Cancer Outcomes, Research and Evaluation optimal utilisation model was adapted for patients with MCOD to provide a benchmark. RESULTS: Of 17 687 participants diagnosed with cancer after completion of the baseline questionnaire, 2392 had MCOD. Of patients with MCOD, 25% had primary lung cancer, which was the most common site. The actual radiotherapy utilisation rate for all patients was 32.3%, lower than the optimal of 45.0%. From multivariable analysis, patients who were aged ≥80 years and/or needed help with daily tasks and/or had a Charlson Comorbidity Index ≥2 were less likely to receive radiotherapy. CONCLUSIONS: Actual uptake of radiotherapy was below optimal. Elderly patients and/or those with more comorbidities were less likely to receive radiotherapy. These results suggest a potential role for advocacy and education around radiotherapy for these patient groups.


Assuntos
Neoplasias Pulmonares , Radioterapia (Especialidade) , Idoso , Humanos , Medicare , New South Wales/epidemiologia , Qualidade de Vida , Estados Unidos
6.
Radiother Oncol ; 156: 174-180, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33359268

RESUMO

BACKGROUND AND PURPOSE: There is a paucity of studies examining variation in the use of palliative radiation therapy (RT) fractionation for brain metastases. The aim of this study is to assess variation in palliative RT fractionation given for brain metastases in New South Wales (NSW), Australia, and identify factors associated with variation. MATERIALS AND METHODS: This is a population-based cohort of patients who received whole brain RT (WBRT) for brain metastases (2009-2014), as captured in the NSW Central Cancer Registry. A logistic regression model was used to identify factors associated with fractionation type. RESULTS: Of the 2,698 patients that received WBRT, 1,389 courses (51%) were < 6 fractions, 1,050 courses (39%) were 6-10 fractions, and 259 courses (10%) were > 10 fractions. Older patients were more likely to be treated with shorter courses (P < 0.0001). Patients with primary lung cancers were more likely to receive shorter courses compared with other primary cancers (P < 0.0001). Patients without surgical excision were more likely to receive < 6 fractions compared to those who underwent surgical excision. Shorter courses were more likely to be delivered to patients with the most disadvantaged socioeconomic status (SES) compared with patients with the least disadvantaged SES (P < 0.0001). There were significant fluctuations in the proportion of courses using lower number of fractions over time from 2009 to 2014, but no apparent trend (P = 0.02). There was wide variation in the proportion of shorter courses across residence local health districts, ranging from 24% to 69% for < 6 fractions, 21% to 72% for 6-10 fractions, and 4% to 20% for > 10 fractions (P < 0.0001). CONCLUSION: This study has identified significant unwarranted variations in fractionation for WBRT in NSW. Accelerating the uptake of shorter fractionation regimens, if warranted through evidence, should be prioritised to enhance evidence-based care.


Assuntos
Neoplasias Encefálicas , Cuidados Paliativos , Austrália , Neoplasias Encefálicas/radioterapia , Fracionamento da Dose de Radiação , Humanos , New South Wales
7.
Radiother Oncol ; 154: 299-305, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33217497

RESUMO

BACKGROUND AND PURPOSE: Adoption of single-fraction radiation therapy (SFRT) has not been universal in the palliative treatment of bone metastases, despite evidence supporting its safety and efficacy. The aim of this study was to assess SFRT use for bone metastases in New South Wales (NSW), Australia, and the rate of 30-day mortality (30DM). MATERIALS AND METHODS: This is a population-based cohort of patients who received palliative radiation therapy (RT) for bone metastases (2009-2014), as captured in the NSW Central Cancer Registry. A logistic regression model was used to identify factors associated with fractionation type. The proportion of patients dying within 30-days from treatment start date was calculated. RESULTS: Of the 14,602 courses of palliative RT delivered for bone metastases, 30% were SFRT. SFRT was more likely to be delivered to older patients: ≥80 years (34%) versus < 60 years (28%). Patients with lower socioeconomic status (SES) (35%) were more likely to receive SFRT compared with higher SES (25%). SFRT delivered to patients from outer regional area of residence (34%) were higher compared to those from the major city (29%). The proportion of SFRT delivered to patients with comorbidities ≥2 (34%) was higher than patients with no comorbidity (29%). SFRT was associated with higher 30DM of 21% compared with 11% for multi-fraction RT (MFRT). CONCLUSION: SFRT is underused for the treatment of bone metastases in NSW. This is an impetus to develop tools making SFRT obligatory in this setting unless there is good justification not to.


Assuntos
Neoplasias Ósseas , Cuidados Paliativos , Austrália , Neoplasias Ósseas/radioterapia , Fracionamento da Dose de Radiação , Humanos , New South Wales/epidemiologia , Radioterapia
8.
J Clin Neurosci ; 81: 1-5, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33222894

RESUMO

Intracranial schwannomas not originating from cranial nerves are rare. In this paper, we report a case of a 50-year-old male who presented with worsening headaches, diplopia and nausea over two years. Radiological imaging revealed a large tumour arising from the olfactory groove region with a preoperative diagnosis of olfactory groove meningioma (OGM). Intraoperatively, the tumour originated from the region of the attachment of the falx to the crista galli. The patient recovered without complication and histopathology reported an unexpected diagnosis of WHO Grade 1 schwannoma. However, as olfactory groove schwannomas (OGSs) cannot be distinguished from olfactory ensheathing cell tumours (OECTs), it is possible that the tumour could have been either an OGS or an OECT. Distinguishing between OGSs, OECTs and OGMs preoperatively is difficult. OGMs exhibit distinct histopathological features from OGSs/OECTs, however, OGSs and OECTs currently cannot be distinguished from each other. Here, we review the literature to discuss the differentiating features and cellular origins of these three tumours.


Assuntos
Fossa Craniana Anterior/patologia , Neurilemoma/diagnóstico , Neoplasias da Base do Crânio/diagnóstico , Diagnóstico Diferencial , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Pessoa de Meia-Idade , Neurilemoma/cirurgia , Neoplasias da Base do Crânio/cirurgia
9.
Clin Oncol (R Coll Radiol) ; 32(11): 775-780, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32646615

RESUMO

Palliative radiotherapy (PRT) makes up about half of all courses delivered in radiotherapy departments. It is effective in the management of common complications of cancer and is relatively inexpensive. About one third of cancer patients receive PRT within the last 2 years of life. One quarter of all patients who receive radiotherapy will undergo a second or subsequent course, mostly for palliative indications. There is considerable variation in practice, both within and between jurisdictions. This has been attributed to inconsistencies in guidelines, physician variation and differing financial incentives. Because of the widespread use of hypofractionation, variation in PRT fractionation has a lower effect on departmental capacity than variation in radical and adjuvant treatments. Excessive fractionation places an unnecessary burden on frail patients at the end of their lives and uses scarce healthcare resources. With appropriate case selection, the increased cost of fractionation or more conformal treatments can be justified where clinical benefit is expected.


Assuntos
Neoplasias/radioterapia , Cuidados Paliativos/economia , Humanos , Cuidados Paliativos/métodos
10.
Clin Oncol (R Coll Radiol) ; 32(5): 282-291, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32007353

RESUMO

AIMS: Actual radiotherapy utilisation rates tend to be lower than the estimated optimal rates. Little is known about the factors contributing to this difference. Our aim was to identify factors associated with radiotherapy receipt for a cohort of cancer patients in New South Wales (NSW), Australia. MATERIALS AND METHODS: In total, 267 153 participants in the NSW 45 and Up Study completed a questionnaire during 2006-2009 providing detailed health and socio-demographic information and consented to record linkage with administrative health datasets. Single primary cancers diagnosed after study enrolment were identified through linkage with the NSW Cancer Registry to December 2013. Radiotherapy receipt was determined from claims to the Medicare Benefits Schedule and/or records in the NSW Admitted Patient Data Collection (2006 to June 2016). Competing risks regression was used to examine associations between health and socio-demographic characteristics and radiotherapy treatment. RESULTS: Of 17 873 patients with an incident cancer, 5414 (30.3%) received radiotherapy during follow-up (median 5.3 years). Patients less likely to receive radiotherapy were aged <60 or 80+ years, female, had a Charlson co-morbidity index of 1+, needed help with daily tasks or lived ≥100 km from the nearest radiotherapy centre. CONCLUSION: Distinct subgroups of patients are less likely to receive radiotherapy. Advocacy and/or policy changes are needed to improve access.


Assuntos
Neoplasias/radioterapia , Radioterapia/estatística & dados numéricos , Sistema de Registros/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/patologia , New South Wales/epidemiologia , Inquéritos e Questionários
11.
J Pediatr Urol ; 15(6): 609.e1-609.e4, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31439431

RESUMO

BACKGROUND: The acute scrotum is a common emergency presentation, and the priority is to exclude testicular torsion, which typically requires scrotal exploration. The accuracy of electronic discharge summaries (EDSs) for patients undergoing acute scrotal exploration has previously been shown to be poor. OBJECTIVE: The objective of this study was to assess accuracy of EDS in patients undergoing acute scrotal exploration in a tertiary paediatric hospital. This study aimed to determine if a new EDS system, whereby the operative procedure is automatically transcribed into the EDS, improves the information within the EDS. METHODS: Retrospective review of the EDS for all patients undergoing acute scrotal exploration between 1st April 2014 and 31st March 2016 was carried out. During this period, a new EDS system, whereby the operative procedure is automatically transcribed to the EDS, was introduced on 20th June 2015. The old system (1st April 2014 to 19th June 2015) was compared with the new system (20th August 2015 to 31st March 2016). RESULTS: A total of 181 patients were included. A diagnosis was not documented in 25 (14%) and was inconsistent with the operation notes in 56 (31%). An operative procedure was not documented at all in 13 (7%) and was inconsistent with the operation notes in 43 (24%). The laterality of pain was not documented and/or incorrect in 11 (6%). The new system in which the operative procedure is automatically transcribed to the EDS resulted in an improvement of diagnoses (78% vs 96%; p = 0.0022; old vs new) and procedures (95% vs 100%; p = 0.0218; old vs new) being documented but not the accuracy. CONCLUSION: The EDS prepared for patients undergoing acute scrotal exploration frequently exhibit inaccuracies; a system that automatically transcribes the operative procedure into the EDS results in modest improvement.


Assuntos
Registros Eletrônicos de Saúde , Serviço Hospitalar de Emergência/estatística & dados numéricos , Alta do Paciente/estatística & dados numéricos , Melhoria de Qualidade , Torção do Cordão Espermático/cirurgia , Centros de Atenção Terciária/estatística & dados numéricos , Procedimentos Cirúrgicos Urológicos Masculinos/estatística & dados numéricos , Adolescente , Emergências , Humanos , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos , Escroto/cirurgia
12.
Case Rep Infect Dis ; 2019: 2094372, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31016054

RESUMO

Crohn's disease exacerbations can often be associated with bacterial infections causing gastroenteritis. We report a child who experienced exacerbation of his Crohn's disease associated with a positive stool culture for Edwardsiella tarda (E. tarda). Endoscopy showed features of moderate inflammation similar to exacerbation of Crohn's disease. The patient was treated simultaneously with intravenous steroids and antibiotics, and his symptoms resolved. This case report highlights the importance of clinicians being able to promptly recognize and treat concurrent bacterial infections in Crohn's disease exacerbations.

13.
Clin Oncol (R Coll Radiol) ; 30(11): 686-691, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30195605

RESUMO

The desire to utilise soft-tissue image guidance at the time of radiation treatment has led to the development of several hybrid magnetic resonance imaging (MRI) linear accelerators (linacs). These systems have the potential to realise the benefits of MRI on the treatment table with the ability of real-time motion management and adaption on a patient-specific basis. There are several MRI-linacs currently being implemented covering both low and high magnetic field strength and two beam-field orientations. Clinical trials have only recently begun with this technology, but their future use as standard radiotherapy practice seems assured. This review article summarises the challenges faced in developing such hybrid technology, the differences and advantages of each of the currently exploited solutions, and their current status.


Assuntos
Imageamento por Ressonância Magnética , Aceleradores de Partículas , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Humanos
14.
Cell Transplant ; 27(6): 879-889, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29882418

RESUMO

Olfactory ensheathing cells (OECs) are glia reported to sustain the continuous axon extension and successful topographic targeting of the olfactory receptor neurons responsible for the sense of smell (olfaction). Due to this distinctive property, OECs have been trialed in human cell transplant therapies to assist in the repair of central nervous system injuries, particularly those of the spinal cord. Though many studies have reported neurological improvement, the therapy remains inconsistent and requires further improvement. Much of this variability stems from differing olfactory cell populations prior to transplantation into the injury site. While some studies have used purified cells, others have used unpurified transplants. Although both preparations have merits and faults, the latter increases the variability between transplants received by recipients. Without a robust purification procedure in OEC transplantation therapies, the full potential of OECs for spinal cord injury may not be realised.


Assuntos
Neuroglia/transplante , Bulbo Olfatório/citologia , Traumatismos da Medula Espinal/terapia , Animais , Separação Celular/métodos , Transplante de Células/métodos , Humanos , Regeneração Nervosa , Neuroglia/citologia , Bulbo Olfatório/transplante , Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia
15.
Phys Med Biol ; 63(13): 135005, 2018 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-29799815

RESUMO

This work describes the first imaging studies on a 1.0 Tesla inline MRI-Linac using a dedicated transmit/receive RF body coil that has been designed to be completely radio transparent and provide optimum imaging performance over a large patient opening. A series of experiments was performed on the MRI-Linac to investigate the performance and imaging characteristics of a new dedicated volumetric RF coil: (1) numerical electromagnetic simulations were used to measure transmit efficiency in two patient positions; (2) image quality metrics of signal-to-noise ratio (SNR), ghosting and uniformity were assessed in a large diameter phantom with no radiation beam; (3) radiation induced effects were investigated in both the raw data (k-space) and image sequences acquired with simultaneous irradiation; (4) radiation dose was measured with and without image acquisition; (5) RF heating was studied using an MR-compatible fluoroptic thermometer and; (6) the in vivo image quality and versatility of the coil was demonstrated in normal healthy subjects for both supine and standing positions. Daily phantom measurements demonstrated excellent imaging performance with stable SNR over a period of 3 months (42.6 ± 0.9). Simultaneous irradiation produced no statistical change in image quality (p > 0.74) and no interference in raw data for a 20 × 20 cm radiation field. The coil was found to be efficient over large volumes and negligible RF heating was observed. Volunteer scans acquired in both supine and standing positions provided artefact free images with good anatomical visualisation. The first completely radio transparent RF coil for use on a 1.0 Tesla MRI-Linac has been described. There is no impact on either the imaging or dosimetry performance with a simultaneous radiation beam. The open design enables imaging and radiotherapy guidance in a variety of positons.


Assuntos
Imageamento por Ressonância Magnética/instrumentação , Aceleradores de Partículas , Ondas de Rádio , Humanos , Imagens de Fantasmas , Radiometria , Razão Sinal-Ruído , Cirurgia Assistida por Computador
16.
Physiol Res ; 67(Suppl 1): S27-S35, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31774298

RESUMO

On March 4, 2017 at the age of 68, Sidney George Shaw (Sid) unexpectedly died from complications following surgery, only four years after retiring from the University of Bern. Trained in biochemistry at Oxford University, Sid had quickly moved into molecular pharmacology and became a key investigator in the field of enzyme biochemistry, vasoactive peptide research, and receptor signaling. Sid spent half his life in Switzerland, after moving to the University of Bern in 1984. This article, written by his friends and colleagues who knew him and worked with him during different stages of his career, summarizes his life, his passions, and his achievements in biomedical research. It also includes personal memories relating to a dear friend and outstanding scientist whose intellectual curiosity, humility, and honesty will remain an example to us all.


Assuntos
Bioquímica/história , Farmacologia/história , Endotelinas/história , Inglaterra , História do Século XX , História do Século XXI , Neurofarmacologia/história , Suíça
17.
Artigo em Inglês | MEDLINE | ID: mdl-28782145

RESUMO

BACKGROUND: The gut hormone motilin stimulates gastrointestinal motility by inducing gastric phase III of the migrating motor complex (MMC) and enhancing the rate of gastric emptying. Camicinal (GSK962040), a small molecule motilin receptor agonist, has been shown to increase gastrointestinal motility. METHODS: In this proof of concept study the effects of camicinal on MMC activity, esophageal and gastric pH was evaluated in eight healthy volunteers as a secondary endpoint. Doses of 50 and 150 mg were compared to placebo for a period of 24 hours in a double-blinded randomized crossover trial. KEY RESULTS: The 50 mg dose (n=4) of camicinal had no significant impact on gastroduodenal manometry or pH parameters. A single dose of 150 mg (n=4) induced a gastric phase III after 0:34 h (0:25-0:58), which was significantly faster compared to placebo (18:15 h (4:32-22:16); P=.03). Moreover, the high dose significantly increased the occurrence of gastric phase III contractions compared to placebo (12% vs 39%; P=.0003). This increase in gastric phase III contractions during a period of 24 hour was due to an increased occurrence of gastric phases III during the daytime (5% vs 50%; P=.0001). The same dose however did not affect small bowel manometry parameters or esophageal and gastric pH. CONCLUSIONS AND INFERENCES: Considering its stimulating effect on the MMC and gastric emptying, camicinal is an attractive candidate for the treatment of gastroparesis and gastroesophageal reflux disease. This trial was registered at clinicaltrials.gov as NCT00562848.


Assuntos
Esvaziamento Gástrico/efeitos dos fármacos , Fármacos Gastrointestinais/administração & dosagem , Complexo Mioelétrico Migratório/efeitos dos fármacos , Piperazinas/administração & dosagem , Piperidinas/administração & dosagem , Receptores dos Hormônios Gastrointestinais/agonistas , Receptores de Neuropeptídeos/agonistas , Adolescente , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Adulto Jovem
18.
Radiother Oncol ; 126(2): 191-197, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29229506

RESUMO

BACKGROUND: To describe the population benefit of radiotherapy in a high-income setting if evidence-based guidelines were routinely followed. METHODS: Australian decision tree models were utilized. Radiotherapy alone (RT) benefit was defined as the absolute proportional benefit of radiotherapy compared with no treatment for radical indications, and of radiotherapy over surgery alone for adjuvant indications. Chemoradiotherapy (CRT) benefit was the absolute incremental benefit of concurrent chemoradiotherapy over RT. Five-year local control (LC) and overall survival (OS) benefits were measured. Citation databases were systematically queried for benefit data. Meta-analysis and sensitivity analysis were performed. FINDINGS: 48% of all cancer patients have indications for radiotherapy, 34% curative and 14% palliative. RT provides 5-year LC benefit in 10.4% of all cancer patients (95% Confidence Interval 9.3, 11.8) and 5-year OS benefit in 2.4% (2.1, 2.7). CRT provides 5-year LC benefit in an additional 0.6% of all cancer patients (0.5, 0.6), and 5-year OS benefit for an additional 0.3% (0.2, 0.4). RT benefit was greatest for head and neck (LC 32%, OS 16%), and cervix (LC 33%, OS 18%). CRT LC benefit was greatest for rectum (6%) and OS for cervix (3%) and brain (3%). Sensitivity analysis confirmed a robust model. INTERPRETATION: Radiotherapy provides significant 5-year LC and OS benefits as part of evidence-based cancer care. CRT provides modest additional benefits.


Assuntos
Neoplasias/radioterapia , Austrália , Quimiorradioterapia , Bases de Dados Factuais , Árvores de Decisões , Medicina Baseada em Evidências , Fidelidade a Diretrizes , Humanos , Terapia Neoadjuvante , Neoplasias/tratamento farmacológico , Neoplasias/mortalidade , Radioterapia Adjuvante
19.
Equine Vet J ; 50(4): 446-451, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29044678

RESUMO

BACKGROUND: Despite the paucity of data available, orally administered angiotensin-converting enzyme (ACE) inhibitors are empirically used in horses with valvular regurgitation. OBJECTIVE: Evaluate the echocardiographic and hormonal changes in response to oral benazepril in horses with left-sided valvular regurgitation. STUDY DESIGN: Prospective, randomised double-blind, placebo-controlled trial. METHODS: Horses with mitral valve (MR) and/or aortic valve regurgitation (AR) received oral benazepril (n = 6) at a dosage of 1 mg/kg q 12 h or a placebo (n = 5) for 28 days. Echocardiography was performed before drug administration and after 28 days of treatment. Plasma renin activity, serum ACE activity, angiotensin II concentration, aldosterone concentration and biochemical variables were measured before drug administration and after 7 and 28 days of treatment. RESULTS: Relative to baseline, horses treated with benazepril had statistically significant reduction in left ventricular internal diameter in systole (mean difference between groups = -0.97 cm; 95% CI = -1.5 to -0.43 cm), aortic sinus diameter (-0.31 cm; -0.54 to -0.07 cm), and percentage of the aortic annulus diameter occupied by the base of the AR jet (-17.05%; -31.17 to -2.93%) compared with horses receiving a placebo. In addition, horses treated with benazepril had a significantly greater increase in cardiac output (11.95 L/min; 1.17-22.73 L/min) and fractional shortening (7.59%; 3.3-11.88%) compared with horses receiving a placebo. Despite profound serum ACE inhibition, renin activity and concentrations of angiotensin II and aldosterone were not significantly different between treatment groups or among time points. MAIN LIMITATIONS: Very small sample size and short treatment period. CONCLUSIONS: Treatment with oral benazepril resulted in statistically significant echocardiographic changes that might indicate reduced cardiac afterload in horses with left-sided valvular regurgitation. Additional studies with a larger sample size will be necessary to determine if administration of benazepril is beneficial in horses with valvular regurgitation. The Summary is available in Spanish - see Supporting Information.


Assuntos
Insuficiência da Valva Aórtica/veterinária , Benzazepinas/uso terapêutico , Doenças dos Cavalos/tratamento farmacológico , Administração Oral , Animais , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/tratamento farmacológico , Benzazepinas/administração & dosagem , Método Duplo-Cego , Ecocardiografia , Feminino , Cavalos , Masculino
20.
Bull Entomol Res ; 108(3): 283-294, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28786374

RESUMO

Understanding pest population dynamics and seasonal phenology is a critical component of modern integrated pest-management programs. Accurate forecasting allows timely, cost-effective interventions, including maximum efficacy of, for example, biological control and/or sterile insect technique. Due to the variation in life stage-related sensitivity toward climate, insect pest population abundance models are often not easily interpreted or lack direct relevance to management strategies in the field. Here we apply a process-based (biophysical) model that incorporates climate data with life stage-dependent physiology and life history to attempt to predict Eldana saccharina life stage and generation turnover in sugarcane fields. Fitness traits are modelled at two agricultural locations in South Africa that differ in average temperature (hereafter a cold and a warm site). We test whether the life stage population structures in the field entering winter and local climate during winter directly affect development rates, and therefore interact to determine the population dynamics and phenological responses of E. saccharina in subsequent spring and summer seasons. The model predicts that: (1) E. saccharina can cycle through more generations at the warm site where fewer hours of cold and heat stress are endured, and (2) at the cold site, overwintering as pupae (rather than larvae) confer higher relative fitness and fecundity in the subsequent summer adult moths. The model predictions were compared with a large dataset of field observations from scouting records. Model predictions for larval presence (or absence) generally overlapped well with positive (or negative) scout records. These results are important for integrated pest management strategies by providing a useful foundation for future population dynamics models, and are applicable to a variety of agricultural landscapes, but especially the sugarcane industry of South Africa.


Assuntos
Clima , Modelos Biológicos , Mariposas/crescimento & desenvolvimento , Animais , Feminino , Aptidão Genética
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