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1.
Am J Perinatol ; 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37072014

RESUMO

OBJECTIVE: To identify psychological, medical, and socioenvironmental risk factors for maternal postpartum depression (PPD) and severe psychological distress (SPD) at intensive care nursery discharge among mothers of very preterm infants. STUDY DESIGN: We studied 562 self-identified mothers of 641 infants born <30 weeks who were enrolled in the Neonatal Neurobehavior and Outcomes in Very Preterm Infants Study (NOVI) conducted in nine university-affiliated intensive care nurseries. Enrollment interviews collected socioenvironmental data, depression, and anxiety diagnoses prior to and during the study pregnancy. Standardized medical record reviews ascertained prenatal substance use, maternal and neonatal medical complications. The Edinburgh Postnatal Depression Scale and Brief Symptom Inventory were administered at nursery discharge to screen for PPD and SPD symptoms, respectively. RESULTS: Unadjusted analyses indicated mothers with positive screens for depression (n = 76, 13.5%) or severe distress (n = 102, 18.1%) had more prevalent prepregnancy/prenatal depression/anxiety, and their infants were born at younger gestational ages, with more prevalent bronchopulmonary dysplasia, and discharge after 40 weeks postmenstrual age. In multivariable analyses, prior depression or anxiety was associated with positive screens for PPD (risk ratio [RR]: 1.6, 95% confidence interval [CI]: 1.1-2.2) and severe distress (RR: 1.6, 95% CI: 1.1-2.2). Mothers of male infants had more prevalent depression risk (RR: 1.7, 95% CI: 1.1-2.4), and prenatal marijuana use was associated with severe distress risk (RR: 1.9, 95% CI: 1.1-2.9). Socioenvironmental and obstetric adversities were not significant after accounting for prior depression/anxiety, marijuana use, and infant medical complications. CONCLUSION: Among mothers of very preterm newborns, these multicenter findings extend others' previous work by identifying additional indicators of risk for PPD and SPD associated with a history of depression, anxiety, prenatal marijuana use, and severe neonatal illness. Findings could inform designs for continuous screening and targeted interventions for PPD and distress risk indicators from the preconception period onward. KEY POINTS: · Preconceptional and prenatal screening for postpartum depression and severe distress may inform care.. · Prior depression, anxiety, and neonatal complications predicted severe distress and depression symptoms at NICU discharge.. · Readily identifiable risk factors warrant continuous NICU screening and targeted interventions to improve outcomes..

2.
J Appl Clin Med Phys ; 16(1): 5238, 2015 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-25679179

RESUMO

For accurate delivery of volumetric-modulated arc therapy (VMAT), the gantry position should be synchronized with the multileaf collimator (MLC) leaf positions and the dose rate. This study, therefore, aims to implement quality control (QC) of VMAT synchronization, with as few arcs as possible and with minimal data handling time, using portal imaging. A steel bar of diameter 12 mm is accurately positioned in the G-T direction, 80 mm laterally from the isocenter. An arc prescription irradiates the bar with a 16 mm × 220 mm field during a complete 360° arc, so as to cast a shadow of the bar onto the portal imager. This results in a sinusoidal sweep of the field and shadow across the portal imager and back. The method is evaluated by simulating gantry position errors of 1°-9° at one control point, dose errors of 2 monitor units to 20 monitor units (MU) at one control point (0.3%-3% overall), and MLC leaf position errors of 1 mm - 6 mm at one control point. Inhomogeneity metrics are defined to characterize the synchronization of all leaves and of individual leaves with respect to the complete set. Typical behavior is also investigated for three models of accelerator. In the absence of simulated errors, the integrated images show uniformity, and with simulated delivery errors, irregular patterns appear. The inhomogeneity metrics increase by 67% due to a 4° gantry position error, 33% due to an 8 MU (1.25%) dose error, and 70% due to a 2 mm MLC leaf position error. The method is more sensitive to errors at gantry angle 90°/270° than at 0°/180° due to the geometry of the test. This method provides fast and effective VMAT QC suitable for inclusion in a monthly accelerator QC program. The test is able to detect errors in the delivery of individual control points, with the possibility of using movie images to further investigate suspicious image features.


Assuntos
Diagnóstico por Imagem , Neoplasias/radioterapia , Aceleradores de Partículas/normas , Garantia da Qualidade dos Cuidados de Saúde/métodos , Controle de Qualidade , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Humanos , Dosagem Radioterapêutica
3.
Plants (Basel) ; 13(2)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38256757

RESUMO

Atmospheric carbon dioxide (CO2) concentrations are increasing and may exceed 800 ppm by 2100. This is increasing global mean temperatures and the frequency and severity of heatwaves. Recently, we showed for the first time that the combination of short-term warming and elevated carbon dioxide (eCO2) caused extreme upward bending (i.e., hyponasty) of leaflets and leaf stems (petioles) in tomato (Solanum lycopersicum), which reduced growth. Here, we examined additional species to test the hypotheses that warming + eCO2-induced hyponasty is restricted to compound-leaved species, and/or limited to the Solanaceae. A 2 × 2 factorial experiment with two temperatures, near-optimal and supra-optimal, and two CO2 concentrations, ambient and elevated (400, 800 ppm), was imposed on similarly aged plants for 7-10 days, after which final petiole angles were measured. Within Solanaceae, compound-leaf, but not simple-leaf, species displayed increased hyponasty with the combination of warming + eCO2 relative to warming or eCO2 alone. In non-solanaceous species, hyponasty, leaf-cupping, and changes in leaf pigmentation as a result of warming + eCO2 were variable across species.

4.
Cancer Med ; 13(12): e7325, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38899493

RESUMO

AIM: There has been significant progress made in developing novel targeted therapies in the neoadjuvant setting for non-metastatic HER2-positive breast cancer, which may be used in combination with conventional chemotherapy to optimise pathological responses at surgery. However, these therapies, particularly the chemotherapeutic components, may portend significant and long-lasting toxicity. Hence, de-escalation of treatment intensity has been an area of interest and was evaluated in the phase II NeoSphere study. Herein, we report the real-world pathological and survival outcomes from neoadjuvant taxane and dual HER2 blockade recorded at our centre. METHODS: This was a retrospective cohort study of patients receiving neoadjuvant pertuzumab, trastuzumab and taxane chemotherapy for non-metastatic HER2-positive breast cancer at a single centre in Sydney, Australia. We collected data pertaining to baseline demographic characteristics, pathological response rates, post-surgical prescribing patterns and also undertook survival analyses for invasive disease-free survival (iDFS) as well as exploratory analyses for correlations between pre-specified clinicopathologic factors and pathological response at surgery. RESULTS: Our population was largely similar at baseline to the NeoSphere study. 71 patients were included in the final analysis. 61% achieved a pathological complete response (pCR). Three patients received conventional chemotherapy in the adjuvant setting. 92% of included patients were alive and disease-free at 3 years of follow-up. Only 3 events of recurrence or death were recorded at a median follow-up of 32 months. No significant difference in iDFS was noted between patients achieving pCR and those with residual disease at surgery. CONCLUSION: This study demonstrates that de-escalated adjuvant treatment for HER2-positive early breast cancer achieved favourable pathological and long-term outcomes comparable to large trials, some utilising more intensive chemotherapeutic components.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias da Mama , Terapia Neoadjuvante , Receptor ErbB-2 , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/metabolismo , Terapia Neoadjuvante/métodos , Pessoa de Meia-Idade , Receptor ErbB-2/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos Retrospectivos , Adulto , Idoso , Austrália , Estadiamento de Neoplasias , Resultado do Tratamento , Trastuzumab/uso terapêutico , Trastuzumab/administração & dosagem , Taxoides/administração & dosagem , Taxoides/uso terapêutico , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Hidrocarbonetos Aromáticos com Pontes/administração & dosagem , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Quimioterapia Adjuvante/métodos
5.
J Appl Clin Med Phys ; 14(2): 4136, 2013 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-23470941

RESUMO

The Agility multileaf collimator (Elekta AB, Stockholm, Sweden) has 160 leaves of projected width 0.5 cm at the isocenter, with maximum leaf speed 3.5 cms-1. These characteristics promise to facilitate fast and accurate delivery of radiotherapy, particularly volumetric-modulated arc therapy (VMAT). The aim of this study is therefore to create a beam model for the Pinnacle3 treatment planning system (Philips Radiation Oncology Systems, Fitchburg, WI), and to use this beam model to explore the performance of the Agility MLC in delivery of VMAT. A 6 MV beam model was created and verified by measuring doses under irregularly shaped fields. VMAT treatment plans for five typical head-and-neck patients were created using the beam model and delivered using both binned and continuously variable dose rate (CVDR). Results were compared with those for an MLCi unit without CVDR. The beam model has similar parameters to those of an MLCi model, with interleaf leakage of only 0.2%. The verification of irregular fields shows a mean agreement between measured and planned dose of 1.3% (planned dose higher). The Agility VMAT head-and-neck plans show equivalent plan quality and delivery accuracy to those for an MLCi unit, with 95% of verification measurements within 3% and 3 mm of planned dose. Mean delivery time is 133 s with the Agility head and CVDR, 171 s without CVDR, and 282 s with an MLCi unit. Pinnacle3 has therefore been shown to model the Agility MLC accurately, and to provide accurate VMAT treatment plans which can be delivered significantly faster with Agility than with an MLCi.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Radiometria/instrumentação , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/instrumentação , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/instrumentação , Radioterapia de Intensidade Modulada/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Dosagem Radioterapêutica , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Philos Trans R Soc Lond B Biol Sci ; 375(1804): 20200038, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32536312

RESUMO

Dungeness crabs (Metacarcinus magister) are ecologically and economically important in the coastal Northeast Pacific, yet relatively little is currently known about their feeding behaviour in the wild or their natural diet. Trophic biomarkers, such as fatty acids (FA), can be used to reveal trophic interactions. We used two feeding experiments to assess differences in FA composition of juvenile crabs fed different known foods to evaluate how they modify and integrate dietary FA into their own tissues and determine whether crab FA reflect diet changes over a six-week period. These experimental results were then compared with the FA signatures of wild caught juvenile crab with undetermined diets. We found that juvenile Dungeness crabs fed different foods assimilated dietary FA into their tissues and were distinct in their FA signatures when analysed with multivariate statistics. Experimentally fed juvenile crabs contained greater proportions of the most abundant long-chain polyunsaturated fatty acids (LCPUFA, >C20) than their foods. Crabs fed foods lacking in LCPUFA, particularly DHA (22:6ω3, docosahexaenoic acid), did not survive or grew slower than crabs fed other foods. This suggests that LCPUFA are physiologically important for this species and indicates biosynthesis of these FA does not occur or is not sufficient to meet their needs. This article is part of the theme issue 'The next horizons for lipids as 'trophic biomarkers': evidence and significance of consumer modification of dietary fatty acids'.


Assuntos
Braquiúros/química , Dieta , Ácidos Graxos/metabolismo , Animais
7.
Asia Pac J Clin Oncol ; 16(3): 103-107, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31218842

RESUMO

AIMS: Internationally, there has recently been growing interest in the use of neoadjuvant pertuzumab and trastuzumab in patients with non-metastatic HER-2 positive breast cancer following the NEOSPHERE trial in 2012. However, pertuzumab is currently not funded by the Pharmaceutical Benefits Scheme (PBS) in Australia for use in this setting. The authors sought to assess the clinical and pathological response rates at the time of surgery in patients who received neoadjuvant dual anti-HER2 and taxane therapy in a multidisciplinary breast cancer unit. METHODS: A retrospective case series of all patients treated with the neoadjuvant therapy, and who had definitive surgery was conducted. Demographic data, size, grade, tumor type, receptor status prior to neoadjuvant treatment, pathological complete response (pCR) rates, and adverse effects were analyzed. RESULTS: Nineteen patients were included in the study. Sixty-eight percent of all patients achieved pCR, of which 54% further demonstrated no residual ductal carcinoma in situ. Eight patients (42%) had N1 disease pretreatment, of these 88% demonstrated total pCR in the axilla and the breast. Most adverse effects to treatment were manageable grade 1-2 side effects. CONCLUSION: This is the first reported Australian experience using neoadjuvant dual anti-HER2 and taxane therapy for HER-2 positive nonmetastatic breast cancer. The authors have demonstrated favorable pCR rates for invasive disease compared to the NEOSPHERE trial (68% vs 46%), with reasonable patient tolerability. Larger collaborative data sets are required to fully evaluate correlation of pCR with survival outcomes, and cost-effectiveness. National funding models need to be considered.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Terapia Neoadjuvante/métodos , Receptor ErbB-2/uso terapêutico , Taxoides/uso terapêutico , Adulto , Idoso , Austrália , Neoplasias da Mama/patologia , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxoides/farmacologia
8.
Chem Commun (Camb) ; (14): 1895-7, 2005 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-15795779

RESUMO

We herein report and discuss electron transport within a Au/H2S nanoscale device and thereby highlight a phenomenon that may be used in the development of a novel on-chip H2S sensor.

9.
Phys Med Biol ; 50(15): N187-94, 2005 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-16030376

RESUMO

Routine quality control (QC) and optimization of image quality of reconstructed images in single photon emission computed tomography (SPECT) and positron emission tomography (PET) remains a relatively qualitative exercise. With the advent of combined SPECT/CT and PET/CT devices, and accurate post hoc co-registration algorithms, the potential exists to utilize high resolution structural information for QC evaluation in addition to their use for anatomical correlation in clinical studies. The aim of this work was to explore, in principle, the uses of x-ray CT data of QC phantoms used in SPECT and PET to develop more objective assessments of performance of the emission tomographic (ET) devices and reconstructed data. A CT reconstruction of a novel ET QC phantom was segmented into the various compartments it contained. Using software, the voxel values in the different compartments were then altered to correspond to the concentration of the radioactivity in the actual scan of the same phantom on the SPECT system. This produces a high resolution version of a 'perfect' ET scan. Image co-registration techniques were then used to spatially align the synthetic high resolution SPECT scan to the measured SPECT scan. Various parameters can then be objectively derived from the registered data, for example, image contrast, spatial resolution, spatial non-uniformity, etc. In this study, we have used this approach to estimate spatial resolution (full width at half maximum, FWHM) and recovered contrast in reconstructed images of a SPECT phantom. Two independent methods were used to measure spatial resolution, obtaining excellent agreement. In conclusion, the ability to produce high resolution synthetic phantoms in emission tomography QC affords an objective approach to assessing system performance and optimizing protocols which is readily automated and quantifiable.


Assuntos
Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Garantia da Qualidade dos Cuidados de Saúde/métodos , Técnica de Subtração , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Armazenamento e Recuperação da Informação/métodos , Imagens de Fantasmas , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada de Emissão de Fóton Único/instrumentação , Tomografia Computadorizada por Raios X/instrumentação , Tomografia Computadorizada por Raios X/métodos
10.
J Appl Clin Med Phys ; 6(3): 13-22, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16143788

RESUMO

The use of image-based 3D treatment planning has significantly increased the complexity of commercially available treatment-planning systems (TPSs). Medical physicists have traditionally focused their efforts on understanding the calculation algorithm; this is no longer possible. A quality assurance (QA) program for our 3D treatment-planning system (ADAC Pinnacle3) is presented. The program is consistent with the American Association of Physicists in Medicine Task Group 53 guidelines and balances the cost-versus-benefit equation confronted by the clinical physicist in a community cancer center environment. Fundamental reproducibility tests are presented as required for a community cancer center environment using conventional and 3D treatment planning. A series of nondosimetric tests, including digitizer accuracy, image acquisition and display, and hardcopy output, is presented. Dosimetric tests include verification of monitor units (MUs), standard isodoses, and clinical cases. The tests are outlined for the Pinnacle3 TPS but can be generalized to any TPS currently in use. The program tested accuracy and constancy through several hardware and software upgrades to our TPS. This paper gives valuable guidance and insight to other physicists attempting to approach TPS QA at fundamental and practical levels.


Assuntos
Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Garantia da Qualidade dos Cuidados de Saúde/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Humanos , Guias de Prática Clínica como Assunto , Garantia da Qualidade dos Cuidados de Saúde/normas , Interpretação de Imagem Radiográfica Assistida por Computador/normas , Radiometria/normas , Planejamento da Radioterapia Assistida por Computador/normas , Radioterapia Conformacional/normas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estados Unidos
11.
Med Dosim ; 30(4): 243-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16275567

RESUMO

Adenocarcinoma of the prostate is currently the most commonly diagnosed cancer in men in the United States, and the second leading cause of cancer mortality. The utilization of radiation therapy is regarded as the definitive local therapy of choice for intermediate- and high-risk disease, in which there is increased risk for extracapsular extension, seminal vesicle invasion, or regional node involvement. High-dose-rate (HDR) brachytherapy is a logical treatment modality to deliver the boost dose to an external beam radiation therapy (EBRT) treatment to increase local control rates. From a treatment perspective, the utilization of a complicated treatment delivery system, the compressed time frame in which the procedure is performed, and the small number of large dose fractions make the implementation of a comprehensive quality assurance (QA) program imperative. One aspect of this program is the QA of the HDR treatment plan. Review of regulatory and medical physics professional publications shows that substantial general guidance is available. We provide some insight to the implementation of an HDR prostate plan program at a community hospital. One aspect addressed is the utilization of the low-dose-rate (LDR) planning system and the use of existing ultrasound image sets to familiarize the radiation therapy team with respect to acceptable HDR implant geometries. Additionally, the use of the LDR treatment planning system provided a means to prospectively determine the relationship between the treated isodose volume and the product of activity and time for the department's planning protocol prior to the first HDR implant. For the first 12 HDR prostate implants, the root-mean-square (RMS) deviation was 3.05% between the predicted product of activity and time vs. the actual plan values. Retrospective re-evaluation of the actual implant data reduced the RMS deviation to 2.36%.


Assuntos
Braquiterapia , Hospitais Comunitários , Desenvolvimento de Programas , Neoplasias da Próstata/radioterapia , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Planejamento da Radioterapia Assistida por Computador , Algoritmos , Fracionamento da Dose de Radiação , Humanos , Masculino , Radiometria , Reprodutibilidade dos Testes
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