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BACKGROUND: There are few efficacious treatments for mechanical neck pain, with controlled trials suggesting efficacy for muscle relaxants and topical nonsteroidal anti-inflammatory drugs. Although studies evaluating topical lidocaine for back pain have been disappointing, the more superficial location of the cervical musculature suggests a possible role for topical local anesthetics. METHODS: This study was a randomized, double-blind, placebo-controlled crossover trial performed at four U.S. military, Veterans Administration, academic, and private practice sites, in which 76 patients were randomized to receive either placebo followed by lidocaine patch for 4-week intervals (group 1) or a lidocaine-then-placebo patch sequence. The primary outcome measure was mean reduction in average neck pain, with a positive categorical outcome designated as a reduction of at least 2 points in average neck pain coupled with at least a 5-point score of 7 points on the Patient Global Impression of Change scale at the 4-week endpoint. RESULTS: For the primary outcome, the median reduction in average neck pain score was -1.0 (interquartile range, -2.0, 0.0) for the lidocaine phase versus -0.5 (interquartile range, -2.0, 0.0) for placebo treatment (P = 0.17). During lidocaine treatment, 27.7% of patients experienced a positive outcome versus 14.9% during the placebo phase (P = 0.073). There were no significant differences between treatments for secondary outcomes, although a carryover effect on pain pressure threshold was observed for the lidocaine phase (P = 0.015). A total of 27.5% of patients in the lidocaine group and 20.5% in the placebo group experienced minor reactions, the most common of which was pruritis (P = 0.36). CONCLUSIONS: The differences favoring lidocaine were small and nonsignificant, but the trend toward superiority of lidocaine suggests more aggressive phenotyping and applying formulations with greater penetrance may provide clinically meaningful benefit.
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Anestésicos Locais , Cervicalgia , Humanos , Cervicalgia/tratamento farmacológico , Cervicalgia/induzido quimicamente , Estudos Cross-Over , Medição da Dor , Lidocaína , Resultado do Tratamento , Método Duplo-Cego , Administração TópicaRESUMO
The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education, and professional practice of medical physics. The AAPM has more than 8000 members and is the principal organization of medical physicists in the US. The AAPM will periodically define new practice guidelines for medical physics practice to help advance the science of medical physics and to improve the quality of service to patients throughout the US. Existing medical physics practice guidelines will be reviewed for the purpose of revision or renewal, as appropriate, on their fifth anniversary or sooner. Each medical physics practice guideline represents a policy statement by the AAPM, has undergone a thorough consensus process in which it has been subjected to extensive review, and requires the approval of the Professional Council. The medical physics practice guidelines recognize that the safe and effective use of diagnostic and therapeutic radiology requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published practice guidelines and technical standards by those entities not providing these services is not authorized. The following terms are used in the AAPM practice guidelines: Must and must not: Used to indicate that adherence to the recommendation is considered necessary to conform to this practice guideline. While must is the term to be used in the guidelines, if an entity that adopts the guideline has shall as the preferred term, the AAPM considers that must and shall have the same meaning. Should and should not: Used to indicate a prudent practice to which exceptions may occasionally be made in appropriate circumstances.
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Física Médica , Radioterapia (Especialidade) , Humanos , Estados Unidos , Física Médica/educação , Lista de Checagem , SociedadesRESUMO
This study describes an investigation of the role of non-polar solvents on the growth of cesium lead halide (CsPbX3 X = Br and I) nanoplatelets. We employed two solvents, benzyl ether (BE) and 1-octadecene (ODE), as well as two nucleation and growth mechanisms, one-pot, facilitated by microwave irradiation (MWI)-based heating, and hot-injection, using convection. Using BE and MWI, large mesoscale CsPbBr3 nanoplatelets were produced, whereas use of ODE produced small crystallites. Differences between the products were observed by optical spectroscopies, which showed first band edge absorptions consistent with thicknesses of â¼9 nm [â¼15 monolayer (ML)] for the BE-CsPbBr3 and â¼5 nm (â¼9 ML) for ODE-CsPbBr3. Both products had orthorhombic crystal structures, with the BE-CsPbBr3 revealing significant preferred orientation diffraction signals consistent with the asymmetric and two-dimensional platelet morphology. The differences in the final morphology were also observed for products formed via hot injection, with BE-CsPbBr3 showing thinner square platelets with thicknesses of â¼2 ML and ODE-CsPbBr3 showing similar morphologies and small crystallite sizes. To understand the role solvent plays in crystal growth, we studied lead plumbate precursor (PbBrn2-n) formation in both solvents, as well as solvent plus ligand solutions. The findings suggest that BE dissolves PbBr2 salts to a higher degree than ODE, and that this BE to precursor affinity persists during growth.
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Qualified medical physicists (QMPs) are in a unique position to influence the creation and application of key performance indicators (KPIs) across diverse practices in health care. Developing KPIs requires the involvement of stakeholders in the area of interest. Fundamentally, KPIs should provide actionable information for the stakeholders using or viewing them. During development, it is important to strongly consider the underlying data collection for the KPI, making it automatic whenever possible. Once the KPI has been validated, it is important to setup a review cycle and be prepared to adjust the underlying data or action levels if the KPI is not performing as intended. Examples of specific KPIs for QMPs of common scopes of practice are provided to act as models to aid in implementation. KPIs are a useful tool for QMPs, regardless of the scope of practice or practice environment, to enhance the safety and quality of care being delivered.
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Indicadores de Qualidade em Assistência à Saúde , HumanosRESUMO
Enhanced recovery after surgery (ERAS) protocols have gained increasing popularity over the past 10 years, and its overarching objectives are to improve perioperative morbidity and reduce postoperative length of stay. Consensus guidelines from the ERAS Society specific to major gastrectomy were published in 2014, however since that time, prospective and retrospective studies have expanded the collective evidence for both the content and efficacy of ERAS pathways for gastrectomy. This objective of this review was to summarize recent data pertinent to the preoperative, perioperative, and postoperative management of gastrectomy patients along an ERAS pathway.
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Gastrectomia , Neoplasias Gástricas , Humanos , Tempo de Internação , Complicações Pós-Operatórias , Estudos Prospectivos , Estudos Retrospectivos , Neoplasias Gástricas/cirurgiaRESUMO
PURPOSE: To develop and implement an automated plan check (APC) tool using a Six Sigma methodology with the aim of improving safety and efficiency in external beam radiotherapy. METHODS: The Six Sigma define-measure-analyze-improve-control (DMAIC) framework was used by measuring defects stemming from treatment planning that were reported to the departmental incidence learning system (ILS). The common error pathways observed in the reported data were combined with our departmental physics plan check list, and AAPM TG-275 identified items. Prioritized by risk priority number (RPN) and severity values, the check items were added to the APC tool developed using Varian Eclipse Scripting Application Programming Interface (ESAPI). At 9 months post-APC implementation, the tool encompassed 89 check items, and its effectiveness was evaluated by comparing RPN values and rates of reported errors. To test the efficiency gains, physics plan check time and reported error rate were prospectively compared for 20 treatment plans. RESULTS: The APC tool was successfully implemented for external beam plan checking. FMEA RPN ranking re-evaluation at 9 months post-APC demonstrated a statistically significant average decrease in RPN values from 129.2 to 83.7 (P < .05). After the introduction of APC, the average frequency of reported treatment-planning errors was reduced from 16.1% to 4.1%. For high-severity errors, the reduction was 82.7% for prescription/plan mismatches and 84.4% for incorrect shift note. The process shifted from 4σ to 5σ quality for isocenter-shift errors. The efficiency study showed a statistically significant decrease in plan check time (10.1 ± 7.3 min, P = .005) and decrease in errors propagating to physics plan check (80%). CONCLUSIONS: Incorporation of APC tool has significantly reduced the error rate. The DMAIC framework can provide an iterative and robust workflow to improve the efficiency and quality of treatment planning procedure enabling a safer radiotherapy process.
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Automação , Neoplasias/radioterapia , Garantia da Qualidade dos Cuidados de Saúde/normas , Planejamento da Radioterapia Assistida por Computador/métodos , Planejamento da Radioterapia Assistida por Computador/normas , Software , Lista de Checagem , Humanos , Órgãos em Risco/efeitos da radiação , Estudos Prospectivos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Gestão da Qualidade TotalRESUMO
Extracellular vesicles (EVs) are a population of vesicular bodies originating from cells, and EVs have been proven to have the potential to deliver different cargos, such as RNAs. However, conventional methods are not able to encapsulate long RNAs into EVs efficiently or may compromise the integrity of EVs. In this study, we have devised a strategy to encapsulate long circRNAs (>1000 nt) into EVs by harnessing the sorting mechanisms of cells. This strategy utilizes the inherent richness of circular RNAs in EVs and a genetic engineering method to increase the cytoplasmic concentration of target circRNAs, facilitating highly efficient RNA back-splicing to drive the circularization of RNAs. This allows target circRNAs to load into EVs with high efficiency. Furthermore, we demonstrate the practical applications of this strategy, showing that these circRNAs can be delivered by EVs to recipient cells for protein expression and to mice for gene editing.
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OBJECTIVE: To determine the association between cervical nonorganic pain signs and epidural corticosteroid injection outcomes and coexisting pain and psychiatric conditions. PATIENTS AND METHODS: Seventy-eight patients with cervical radiculopathy who received epidural corticosteroid injection were observed to determine the effects that nonorganic signs have on treatment outcome. A positive outcome was a decrease of 2 or more points in average arm pain, coupled with a score of 5 on a 7-point Patient Global Impression of Change scale 4 weeks after treatment. Nine tests in 5 categories (abnormal tenderness, regional disturbances deviating from normal anatomy, overreaction, discrepancies in examination findings with distraction, and pain during sham stimulation) were modified from previous studies and standardized. Other variables examined for their association with nonorganic signs and outcomes included disease burden, psychopathology, coexisting pain conditions, and somatization. RESULTS: Of the 78 patients, 29% (n=23) had no nonorganic signs, 21% (n=16) had signs in 1 category, 10% (n=8) had signs in 2 categories, 21% (n=16) had signs in 3 categories, 10% (n=8) had signs in 4 categories, and 9% (n=7) had signs in 5 categories. The most common nonorganic sign was superficial tenderness (44%; n=34). Mean number of positive nonorganic categories was higher in individuals with negative treatment outcomes (2.5±1.8; 95% CI, 2.0 to 3.1) compared with those with positive outcomes (1.1±1.3; 95% CI, 0.7 to 1.5; P=.0002). Negative treatment outcomes were most strongly associated with regional disturbances and overreaction. Positive associations were noted between nonorganic signs and multiple pain (P=.011) and multiple psychiatric (P=.028) conditions. CONCLUSION: Cervical nonorganic signs correlate with treatment outcome, pain, and psychiatric comorbidities. Screening for these signs and psychiatric symptoms may improve treatment outcomes. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04320836.
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Radiculopatia , Humanos , Radiculopatia/diagnóstico , Radiculopatia/tratamento farmacológico , Radiculopatia/epidemiologia , Corticosteroides/uso terapêutico , Resultado do Tratamento , Cervicalgia/diagnóstico , Cervicalgia/tratamento farmacológico , Cervicalgia/epidemiologia , ComorbidadeRESUMO
PURPOSE: The dosimetric leaf gap (DLG) in the Varian Eclipse treatment planning system is determined during commissioning and is used to model the effect of the rounded leaf-end of the multileaf collimator (MLC). This parameter attempts to model the physical difference between the radiation and light field and account for inherent leakage between leaf tips. With the increased use of single fraction high dose treatments requiring larger monitor units comes an enhanced concern in the accuracy of leakage calculations, as it accounts for much of the patient dose. This study serves to verify the dosimetric accuracy of the algorithm used to model the rounded leaf effect for the TrueBeam STx, and describes a methodology for determining best-practice parameter values, given the novel capabilities of the linear accelerator such as flattening filter free (FFF) treatments and a high definition MLC (HDMLC). METHODS: During commissioning, the nominal MLC position was verified and the DLG parameter was determined using MLC-defined field sizes and moving gap tests, as is common in clinical testing. Treatment plans were created, and the DLG was optimized to achieve less than 1% difference between measured and calculated dose. The DLG value found was tested on treatment plans for all energies (6 MV, 10 MV, 15 MV, 6 MV FFF, 10 MV FFF) and modalities (3D conventional, IMRT, conformal arc, VMAT) available on the TrueBeam STx. RESULTS: The DLG parameter found during the initial MLC testing did not match the leaf gap modeling parameter that provided the most accurate dose delivery in clinical treatment plans. Using the physical leaf gap size as the DLG for the HDMLC can lead to 5% differences in measured and calculated doses. CONCLUSIONS: Separate optimization of the DLG parameter using end-to-end tests must be performed to ensure dosimetric accuracy in the modeling of the rounded leaf ends for the Eclipse treatment planning system. The difference in leaf gap modeling versus physical leaf gap dimensions is more pronounced in the more recent versions of Eclipse for both the HDMLC and the Millennium MLC. Once properly commissioned and tested using a methodology based on treatment plan verification, Eclipse is able to accurately model radiation dose delivered for SBRT treatments using the TrueBeam STx.
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Planejamento da Radioterapia Assistida por Computador/métodos , Radiometria , Radiocirurgia , Dosagem Radioterapêutica , Reprodutibilidade dos TestesRESUMO
PURPOSE: In external-beam radiation therapy, existing on-board x-ray imaging chains orthogonal to the delivery beam cannot recover 3D target trajectories from a single view in real-time. This limits their utility for real-time motion management concurrent with beam delivery. To address this limitation, the authors propose a novel concept for on-board imaging based on the inverse-geometry Scanning-Beam Digital X-ray (SBDX) system and evaluate its feasibility for single-view 3D intradelivery fiducial tracking. METHODS: A chest phantom comprising a posterior wall, a central lung volume, and an anterior wall was constructed. Two fiducials were placed along the mediastinal ridge between the lung cavities: a 1.5 mm diameter steel sphere superiorly and a gold cylinder (2.6 mm length × 0.9 mm diameter) inferiorly. The phantom was placed on a linear motion stage that moved sinusoidally. Fiducial motion was along the source-detector (z) axis of the SBDX system with ±10 mm amplitude and a programmed period of either 3.5 s or 5 s. The SBDX system was operated at 15 frames per second, 100 kVp, providing good apparent conspicuity of the fiducials. With the stage moving, detector data were acquired and subsequently reconstructed into 15 planes with a 12 mm plane-to-plane spacing using digital tomosynthesis. A tracking algorithm was applied to the image planes for each temporal frame to determine the position of each fiducial in (x,y,z)-space versus time. A 3D time-sinusoidal motion model was fit to the measured 3D coordinates and root mean square (RMS) deviations about the fitted trajectory were calculated. RESULTS: Tracked motion was sinusoidal and primarily along the source-detector (z) axis. The RMS deviation of the tracked z-coordinate ranged from 0.53 to 0.71 mm. The motion amplitude derived from the model fit agreed with the programmed amplitude to within 0.28 mm for the steel sphere and within -0.77 mm for the gold seed. The model fit periods agreed with the programmed periods to within 7%. CONCLUSIONS: Three dimensional fiducial tracking with approximately 1 mm or better accuracy and precision appears to be feasible with SBDX, supporting its use to guide radiotherapy.
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Algoritmos , Marcadores Fiduciais , Imageamento Tridimensional/métodos , Reconhecimento Automatizado de Padrão/métodos , Radioterapia Conformacional/métodos , Radioterapia Guiada por Imagem/métodos , Tomografia Computadorizada por Raios X/métodos , Estudos de Viabilidade , Humanos , Imagens de Fantasmas , Intensificação de Imagem Radiográfica/métodos , Dosagem Radioterapêutica , Radioterapia Guiada por Imagem/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: The purpose of this study was to compare outcomes in patients with anal canal squamous cell carcinoma (SCCA) who were treated with definitive chemoradiotherapy by either intensity-modulated radiation therapy (IMRT) or conventional radiotherapy (CRT). METHODS: Forty-six patients who received definitive chemoradiotherapy from January 1993 to August 2009 were included. Forty-five patients received 5-fluorouracil with mitomycin C (n = 39) or cisplatin (n = 6). Seventeen (37%) were treated with CRT and 29 (63%) with IMRT. The median dose was 54 Gy in both groups. Median follow-up was 26 months (CRT) and 32 months (IMRT). T3-T4 stage (P = .18) and lymph node-positive disease (P = .6) were similar between groups. RESULTS: The CRT group required longer treatment duration (57 days vs 40 days, P < .0001), more treatment breaks (88% vs 34.5%, P = .001), and longer breaks (12 days vs 1.5 days, P < .0001) than patients treated with IMRT. Eleven (65%) patients in the CRT group experienced grade >2 nonhematologic toxicity compared with 6 (21%) patients in the IMRT group (P = .003). The 3-year overall survival (OS), locoregional control (LRC), and progression-free survival were 87.8%, 91.9%, and 84.2%, respectively, for the IMRT groups and 51.8%, 56.7%, and 56.7%, respectively, for the CRT group (all P < .01). On multivariate analysis, T stage, use of IMRT, and treatment duration were associated with OS, and T stage and use of IMRT were associated with LRC. CONCLUSIONS: The use of IMRT was associated with less toxicity, reduced need for treatment breaks, and excellent LRC and OS compared with CRT in patients with SCCA of the anal canal.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Ânus/radioterapia , Carcinoma de Células Escamosas/radioterapia , Neoplasias do Ânus/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Cisplatino/administração & dosagem , Terapia Combinada , Feminino , Fluoruracila/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Radioterapia/métodos , Dosagem Radioterapêutica , Análise de SobrevidaRESUMO
BACKGROUND: Hyperglycemia-induced superoxide production in the mitochondria is known to be the primary cause of diabetic micro- and macro-vascular complications and mitochondrial membranal damage. This study in streptozotocin-induced diabetic Wistar rats investigated the anti-hyperglycemic and mitochondrial membrane protection effects of baicalin, a flavonoid known for its radical scavenging activity. METHODS: The following oral treatments were given to diabetic rats for 30 days: (1) metformin 500 mg/kg, (2) baicalin 120 mg/kg, and (3) metformin 500 mg/kg & baicalin 120 mg/kg, with vehicle-treated diabetic and non-diabetic groups serving as controls. RESULTS: Transmission electron microscopy imaging of pancreatic beta-cells revealed loss of integrity of the inner membrane of the mitochondria in the diabetic rats, which was not observed in the baicalin-treated group. In addition, baicalin and the combined treatment of metformin and baicalin had significantly reduced (p < 0.05) the number of mitochondria with a damaged membrane compared to the diabetic control as well as the metformin-treated group in the hepatic tissues. Baicalin had also increased the plasma leptin content (p < 0.05) versus the diabetic control, which in turn had effected the total expression of hepatic mitochondria per cell indicating its effects in SIRT1 activity. The increase in mitochondrial number was further complemented with similar trends in the hepatic citrate synthase activity. CONCLUSIONS: Baicalin had reduced the hyperglycemia-induced mitochondrial membrane damage, as well as enhanced the effects of metformin, as was observed in the results from the metformin and baicalin treated groups.
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Diabetes Mellitus Experimental/patologia , Flavonoides/farmacologia , Sequestradores de Radicais Livres/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Membranas Mitocondriais/efeitos dos fármacos , Animais , Citrato (si)-Sintase/metabolismo , Complicações do Diabetes/prevenção & controle , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/fisiopatologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/ultraestrutura , Hiperglicemia/fisiopatologia , Hipoglicemiantes/farmacologia , Células Secretoras de Insulina/ultraestrutura , Leptina/sangue , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Metformina/farmacologia , Microscopia Eletrônica de Transmissão , Mitocôndrias/ultraestrutura , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/ultraestrutura , Membranas Mitocondriais/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos WistarRESUMO
Spiral analysis is a computerized method of analyzing upper limb motor physiology through the quantification of spiral drawing. The objective of this study was to determine whether spirals drawn by patients with Niemann-Pick disease type C (NPC) could be distinguished from those of controls, and to physiologically characterize movement abnormalities in NPC. Spiral data consisting of position, pressure, and time were collected from 14 NPC patients and 14 age-matched controls, and were analyzed by the Mann-Whitney U test. NPC spirals were characterized by: lower speed (2.67 vs. 9.56 cm/s, P < 0.001) and acceleration (0.10 vs. 2.04 cm/s(2), P < 0.001), higher loop width variability (0.88 vs. 0.28, P < 0.001), tremor (5/10 vs. 0/10 trials in the dominant hand, P < 0.001), and poor overall spiral rating (2.53 vs. 0.70, P < 0.005). NPC spirals also exhibited sustained drawing pressure profiles that were abnormally invariant with time. Other features, such as the tightness of loop widths, were normal. Our findings reveal that differing aspects of tremor, Parkinsonism, ataxia, and dystonia are quantifiable in NPC patients.
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Movimento/fisiologia , Doença de Niemann-Pick Tipo C/patologia , Doença de Niemann-Pick Tipo C/fisiopatologia , Análise Numérica Assistida por Computador , Extremidade Superior/fisiopatologia , Adolescente , Adulto , Estudos de Casos e Controles , Eletromiografia/métodos , Feminino , Humanos , Masculino , Estatísticas não Paramétricas , Adulto JovemRESUMO
PURPOSE: While critical for safe and accurate radiotherapy, monthly quality assurance of medical linear accelerators is time-consuming and takes physics resources away from other valuable tasks. The previous methods at our institution required 5 hours to perform the mechanical and dosimetric monthly linear accelerator quality assurance tests. An improved workflow was developed to perform these tests with higher accuracy, with fewer error pathways, in significantly less time. METHODS: A commercial ion chamber array (IC profiler, Sun Nuclear, Melbourne, Florida) is combined with automation scripts to consolidate monthly linear accelerator QA. The array was used to measure output, flatness, symmetry, jaw positions, gated dose constancy, energy constancy, collimator walkout, crosshair centering, and dosimetric leaf gap constancy. Treatment plans were combined with automation scripts that interface with Sun Nuclear's graphical user interface. This workflow was implemented on a standard Varian clinac, with no special adaptations, and can be easily applied to other C-arm linear accelerators. RESULTS: These methods enable, in 30 minutes, measurement and analysis of 20 of the 26 dosimetric and mechanical monthly tests recommended by TG-142. This method also reduces uncertainties in the measured beam profile constancy, beam energy constancy, field size, and jaw position tests, compared to our previous methods. One drawback is the increased uncertainty associated with output constancy. Output differences between IC profiler and farmer chamber in plastic water measurements over a 6-month period, across 4 machines, were found to have a 0.3% standard deviation for photons and a 0.5% standard deviation for electrons, which is sufficient for verifying output accuracy according to TG-142 guidelines. To minimize error pathways, automation scripts which apply the required settings, as well as check the exported data file integrity were employed. CONCLUSIONS: The equipment, procedure, and scripts used here reduce the time burden of routine quality assurance tests and in most instances improve precision over our previous methods.
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Aceleradores de Partículas/instrumentação , Aceleradores de Partículas/normas , Garantia da Qualidade dos Cuidados de Saúde , Automação , Humanos , Garantia da Qualidade dos Cuidados de Saúde/métodos , Garantia da Qualidade dos Cuidados de Saúde/normas , Radiometria , Reprodutibilidade dos Testes , Fatores de TempoRESUMO
Oxidative stress is the root cause of diabetic macro- and microvascular complications. Biochemical and epidemiological studies indicate that current treatments for diabetes do not reduce risks of developing complications, suggesting their inability to alleviate the levels of oxidative stress. This study in streptozotocin (STZ)-induced diabetic rats was carried out to investigate the effect of combining the antidiabetic drug, metformin, with an ethanolic extract of Scutellaria baicalensis, a plant whose root is known for its radical scavenging activity. Three groups of STZ-induced diabetic rats were given the following treatments for 30 days: (1) metformin 500 mg/kg, (2) S. baicalensis 400 mg/kg, (3) metformin 500 mg/kg + S. baicalensis extract 400 mg/kg. In addition, vehicle-treated diabetic and nondiabetic controls were used in the experiment. The rats treated with S. baicalensis and metformin + S. baicalensis had elevated hepatic activities of the antioxidant enzymes--superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) compared to the vehicle- and metformin-treated diabetic groups (p < 0.05). Plasma and hepatic lipid peroxide concentrations in the herb-treated and herb + metformin-treated groups were also significantly reduced (p < 0.05). In addition, the combined treatment caused significant elevations of plasma and pancreatic insulin levels and reductions of plasma and hepatic triglycerides (TG) and cholesterol levels. The study thus showed that S. baicalensis enhanced the antidiabetic effect of metformin in STZ-induced diabetic rats by improving the antioxidant status. It also increased pancreatic insulin content as well as improved the lipid profile in these rats.
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Diabetes Mellitus Experimental/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Extratos Vegetais/farmacologia , Animais , Antioxidantes/metabolismo , Glicemia/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/patologia , Modelos Animais de Doenças , Quimioterapia Combinada , Medicamentos de Ervas Chinesas/uso terapêutico , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Metformina/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Scutellaria baicalensis , EstreptozocinaRESUMO
This study investigated the effects of Rehmannia glutinosa individually as well as in combination with the oral hypoglycemic agent, metformin in streptozotocin (STZ)-induced diabetic Wistar rats. R. glutinosa ethanolic extract was prepared and the constituents were characterized using fractionation by column chromatography, followed by high performance liquid chromatography-mass spectrometry. STZ (65 mg/kg) was injected intraperitoneally to induce diabetes in Wistar rats. The diabetic rats were divided into the following groups (each n = 6) and received the respective treatments for 30 days: (1) metformin (500 mg/kg), (2) R. glutinosa (200 mg/kg), (3) metformin (500 mg/kg) and R. glutinosa (200 mg/kg) and (4) diabetic control (DC). A reduction in plasma glucose levels caused by the herb was not as significant as metformin compared to the diabetic control (p < 0.05). However, R. glutinosa-treated group showed reductions in plasma C-reactive protein (CRP) levels compared to the diabetic controls (p < 0.05) as well as metformin-treated group (p < 0.05). An enhanced reduction in CRP concentration was observed in the group receiving both herb and metformin compared to metformin-treated group (p < 0.05). Reduction in CRP levels suggests an anti-inflammatory activity of the herb.
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Antioxidantes/farmacologia , Diabetes Mellitus/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Hipoglicemiantes/farmacologia , Rehmannia/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Proteína C-Reativa/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Quimioterapia Combinada , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Masculino , Ratos , Ratos Wistar , EstreptozocinaRESUMO
Overexpression of chemokine receptor type 4 (CXCR4) has been found to be associated with increased cell proliferation, metastasis and also act as an indicator of poor prognosis in patients with breast cancer. Therefore, new agents that can abrogate CXCR4 expression have potential against breast cancer metastasis. In this study, we examined the potential effect of thymoquinone (TQ), derived from the seeds of Nigella sativa, on the expression and regulation of CXCR4 in breast cancer cells. TQ was found to inhibit the expression of CXCR4 in MDA-MB-231 triple negative breast cancer (TNBC) cells in a dose- and time-dependent manner. It was noted that suppression of CXCR4 by TQ was possibly transcriptionally regulated, as treatment with this drug caused down-regulation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation and suppression of NF-κB binding to the CXCR4 promoter. Pretreatment with a proteasome inhibitor and/or lysosomal stabilization did not affect TQ induced suppression of CXCR4. Down-regulation of CXCR4 was further correlated with the inhibition of CXCL12-mediated migration and invasion of MDA-MB-231 cells. Interestingly, it was observed that the deletion of p65 could reverse the observed anti-invasive/anti-migratory effects of TQ in breast cancer cells. TQ also dose-dependently inhibited MDA-MB-231 tumor growth and tumor vascularity in a chick chorioallantoic membrane assay model. We also observed TQ (2 and 4 mg/kg) treatment significantly suppressed multiple lung, brain, and bone metastases in a dose-dependent manner in a metastasis breast cancer mouse model. Interestingly, H&E and immunohistochemical analysis of bone isolated from TQ treated mice indicated a reduction in number of osteolytic lesions and the expression of metastatic biomarkers. In conclusion, the results indicate that TQ primarily exerts its anti-metastatic effects by down-regulation of NF-κB regulated CXCR4 expression and thus has potential for the treatment of breast cancer.
RESUMO
PURPOSE: To study the impact on nodal coverage and dose to fixed organs at risk when using daily fiducial localization of the prostate to deliver intensity-modulated radiotherapy (IMRT). METHODS AND MATERIALS: Five patients with prostate cancer in whom prostate and pelvic nodes were irradiated with IMRT were studied. Dose was prescribed such that 95% of the prostate planning target volume (PTV) and 90% of the nodal PTV were covered. Random and systematic prostate displacements in the anterior-posterior, superior-inferior, and left-right directions were simulated to shift the original isocenter of the IMRT plan. The composite dose during the course of treatment was calculated. RESULTS: Compared with a static setup, simulating random shifts reduced dose by less than 1.5% for nodal hotspot (i.e., dose to 1 cm(3)), by less than 1% for the 90% nodal PTV coverage, and by less than 0.5% for the nodal mean dose. Bowel and femoral head hotspots were reduced by less than 1.5% and 2%, respectively. A 10-mm systematic offset reduced nodal coverage by up to 10%. CONCLUSION: The use of prostate fiducials for daily localization during IMRT treatment results in negligible changes in dose coverage of pelvic nodes or normal tissue sparing in the absence of a significant systematic offset. This offers a simple and practical solution to the problem of image-guided radiotherapy for prostate cancer when including pelvic nodes.
Assuntos
Neoplasias Pélvicas/radioterapia , Neoplasias da Próstata/radioterapia , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/efeitos adversos , Medição de Risco/métodos , Tomografia Computadorizada por Raios X/métodos , Humanos , Linfonodos/efeitos da radiação , Metástase Linfática , Masculino , Especificidade de Órgãos , Lesões por Radiação/etiologia , Dosagem Radioterapêutica , Radioterapia Assistida por Computador/métodos , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e EspecificidadeRESUMO
The chloroform and hexane fractions and their sub-fractions of Polygonum bistorta (Polygonaceae) were evaluated for their cytotoxic activity against P338 (Murine lymphocytic leukaemia), HepG2 (Hepatocellular carcinoma), J82 (Bladder transitional carcinoma), HL60 (Human leukaemia), MCF7 (Human breast cancer) and LL2 (Lewis lung carcinoma) cancer cell lines in culture. Both the chloroform and hexane fractions and a few of their sub-fractions showed moderate to very good activity against P388, HL60 and LL2 cancer cell lines. Both active and non-active fractions were further investigated for their chemical constituents. A total of nine compounds, viz. 24(E)-ethylidenecycloartanone (1), 24(E)-ethylidenecycloartan-3alpha-ol (2), cycloartane-3,24-dione (3), 24-methylenecycloartanone (4), friedelin (5), 3beta-friedelinol (6), beta-sitosterol (7), gamma-sitosterol (8) and beta-sitosterone (9) were isolated. One of the pure compounds, 24(E)-ethylidenecycloartanone 1, which was obtained in sufficient quantity, was tested for its cytotoxicity against P388, LL2, HL60 and WEHI164 (Murine fibrosarcoma) cancer cell lines but was found to have no activity even at a concentration of 100 microg/mL.
Assuntos
Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/farmacologia , Polygonum/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Clorofórmio , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectroscopia de Ressonância Magnética , Camundongos , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Solventes , Espectrofotometria Infravermelho , Relação Estrutura-AtividadeRESUMO
A hypofractionation treatment protocol for prostate cancer was initiated in our department in December 2003. The treatment regimen consists of a total dose of 36.25 Gy delivered at 7.25 Gy per fraction over 10 days. We discuss the rationale for such a prostate hypofractionation protocol and the need for frequent prostate imaging during treatment. The CyberKnife (Accuray Inc., Sunnyvale, CA), a linear accelerator mounted on a robotic arm, is currently being used as the radiation delivery device for this protocol, due to its incorporation of near real-time kV imaging of the prostate via 3 gold fiducial seeds. Recently introduced conventional linac kV imaging with intensity modulated planning and delivery may add a new option for these hypofractionated treatments. The purpose of this work is to investigate the use of intensity modulated radiotherapy (IMRT) and the Varian Trilogy Accelerator with on-board kV imaging (Varian Medical Systems Inc., Palo Alto, CA) for treatment of our hypofractionated prostate patients. The dose-volume histograms and dose statistics of 2 patients previously treated on the CyberKnife were compared to 7-field IMRT plans. A process of acquiring images to observe intrafraction prostate motion was achieved in an average time of about 1 minute and 40 seconds, and IMRT beam delivery takes about 40 seconds per field. A complete 7-field IMRT plan can therefore be imaged and delivered in 10 to 17 minutes. The Varian Trilogy Accelerator with on-board imaging and IMRT is well suited for image-guided hypofractionated prostate treatments. During this study, we have also uncovered opportunities for improvement of the on-board imaging hardware/software implementation that would further enhance performance in this regard.