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《Journal of Medical Imaging and Radiation Sciences》2022,53(3):460-470
PurposeTo provide means for calculating the dose received by various tissues of the patient, calculate lung shield, and verify received dose using a phantom as a tool for quality assurance for a planned Total Body Irradiation (TBI) procedure in radiotherapy.MethodUsing Microsoft Visual Basic, MATLAB, and Python, a program for Total Body Irradiation Calculation in Radiotherapy (TBICR) is constructed. It uses patient translation and beam zone method for total body irradiation calculations to compute the proper dose received by the patient and determine the lung shield thickness. There are three main user-friendly interfaces in the application. The first one allows the user to upload the TBI topography and estimate the distances needed for TBI calculations. The second one enables the user to count the number of beam zones needed for each point and estimate the effective area (Aeff) for each level. The third interface estimates the velocity required to deliver the relative dose depending on patient separation, Monitor Units (MU), couch speed and travel distance. It allows the user to compute the required lung shield thickness, read any patient's CT DICOM file and acquire dose in any distinct location using machine learning model to predict the dose.ResultsThe TBICR software has been successfully validated by reproducing all of the manual calculations in an exact and timely manner. TBICR generated more accurate results and confirmed the absorbed dose to patient through measurements on Anderson phantom.ConclusionsA computer program for the calculation of total body irradiation (TBI) is described in full. The dose received at each point on the patient, the calculation of lung shield and the determination of the velocity and time required for the couch movement are all made possible using the software. The ease of use, precision, data storage and printing are some important features of the present software. 相似文献
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AimsThe effect of Origanum majorana tea consumption on motor and non-motor symptoms was investigated in patients with idiopathic Parkinson's disease, measured by validated tools.MethodsSixty patients with idiopathic Parkinson's disease and under conventional medication were enrolled voluntarily in the study. All participants were randomized on double-blind to placebo or Origanum majorana. Clinical assessment with validated tools (UPDRSIII, NMSS, and BDI) was done before Origanum majorana or placebo consumption (Day 0) and at the end of the experiment (Day 30).ResultsThe treatment groups were similar at baseline on demographic and clinical variables. During the course of study, nine participants withdrew for reasons of noncompliance and inability to follow-up. Fifty-one participants completed the study. Upon completion of 30 days of treatment, Origanum majorana tea consumption did not decrease the UPDRSIII score ([UPDRSIII] D0 = 18.76 ± 8.58, D30 = 16.52 ± 7.96, p = 0.069) at the p value was 0.07. However, a statistically significant improvement was noted in NMSS and BDI scores (p < 0.0001 and p < 0.0001, respectively). Assessment of the UPDRSIII, NMSS and BDI scores of the patients did not reflect any improvement with placebo. No side effect was detected during the study.ConclusionThese findings show improvement of depressive and non-motor signs in patients with Parkinson's disease in the group that consumed Origanum majorana tea in combination with conventional therapy. Improvement of motor signs may need an extended treatment period. However, more research with a large number of participants and lasting longer than 1 month is needed to argue these findings. 相似文献
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《The Journal of arthroplasty》2022,37(2):252-258
BackgroundThe goal of this study is to investigate the migration and inducible displacement of a bicruciate-stabilized (BCS) total knee arthroplasty implanted using gap balancing (GB) or measured resection (MR) surgical techniques. We hypothesized equal migration and displacement between the techniques.MethodsThe study is a single-blinded, prospective, randomized controlled trial, with allocation of 71 patients to either GB or MR groups. Fifteen patients were withdrawn, resulting in 31 patients in the GB group and 25 in the MR group. Patients received the JOURNEY II? BCS implant. Migration and inducible displacement were evaluated using radiostereometric analysis and patient examinations were performed at a 2-week baseline, and at 6 weeks, 3 months, 6 months, 1 year, and 2 years postoperation.ResultsNo differences (P > .05) existed between GB and MR groups for any measurement of tibial or femoral migration. Both groups had tibial migrations below 0.5 mm from baseline to 6 months, and below 0.2 mm from both 6 months to 1 year and 1-2 years postoperation. No differences (P > .05) were found between GB and MR groups for inducible displacement.ConclusionNo differences were found in implant migration or inducible displacement between GB and MR groups. The BCS implant can be expected to have migration risks on par with industry standards and both surgical techniques are safe and effective options for implantation of this implant design. 相似文献
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Beat-to-beat variability of ventricular repolarization (BVR) has been proposed as a strong predictor of Torsades de Pointes (TdP). BVR is also observed at the myocyte level, and a number of studies have shown the importance of calcium handling in influencing this parameter. The chronic AV block (CAVB) dog is a model of TdP arrhythmia in cardiac hypertrophy, and myocytes from these animals show extensive remodeling, including of Ca2 + handling. This remodeling process also leads to increased BVR. We aimed to determine the role that (local) Ca2 + handling plays in BVR.In isolated LV myocytes an exponential relationship was observed between BVR magnitude and action potential duration (APD) at baseline. Inhibition of Ca2 + release from sarcoplasmic reticulum (SR) with thapsigargin resulted in a reduction of [Ca2 +]i, and of both BVR and APD. Increasing ICaL in the presence of thapsigargin restored APD but BVR remained low. In contrast, increasing ICaL with preserved Ca2 + release increased both APD and BVR. Inhibition of Ca2 + release with caffeine, as with thapsigargin, reduced BVR despite maintained APD. Simultaneous inhibition of Na+/Ca2 + exchange and ICaL decreased APD and BVR to similar degrees, whilst increasing diastolic Ca2 +. Buffering of Ca2 + transients with BAPTA reduced BVR for a given APD to a greater extent than buffering with EGTA, suggesting subsarcolemmal Ca2 + transients modulated BVR to a larger extent than the cytosolic Ca2 + transient.In conclusion, BVR in hypertrophied dog myocytes, at any APD, is strongly dependent on SR Ca2 + release, which may act through modulation of the l-type Ca2 + current in a subsarcolemmal microdomain. 相似文献
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Microorganisms thrive in well-organized biofilm ecosystems. Biofilm-associated cells typically show increased resistance to antibiotics and contribute significantly to treatment failure. This has prompted investigations aimed at developing advanced and novel antimicrobial approaches that could effectively overcome the shortcomings associated with conventional antibiotic therapy. Studies are ongoing to develop effective curative strategies ranging from the use of peptides, small molecules, nanoparticles to bacteriophages, sonic waves, and light energy targeting various structural and physiological aspects of biofilms. In photodynamic therapy, a light source of a specific wavelength is used to irradiate non-toxic photosensitizers such as tetrapyrroles, synthetic dyes or, naturally occurring compounds to generate reactive oxygen species that can exert a lethal effect on the microbe especially by disrupting the biofilm. The photosensitizer preferentially binds to and accumulates in the microbial cells without causing any damage to the host tissue. Currently, photodynamic therapy is increasingly being used for the treatment of oral caries and dental plaque, chronic wound infections, infected diabetic foot ulcers, cystic fibrosis, chronic sinusitis, implant device-associated infections, etc. This approach is recognized as safe, as it is non-toxic and minimally invasive, making it a reliable, realistic, and promising therapeutic strategy for reducing the microbial burden and biofilm formation in chronic infections. In this review article, we discuss the current and future potential strategies of utilizing photodynamic therapy to extend our ability to impede and eliminate biofilms in various medical conditions. 相似文献
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