Gafchromic EBT2 film (lot A091710003) was cut into 1 cm by 1.25 cm strips. A calibrated 6 MV photon beam from a 21EX Clinac (Varian Medical Systems, Palo Alto, CA) was used to deliver 0, 5, 10, 25, 50, 100, 150, 200, 250, 300, 500, and 800 cGy to two pieces of the cut film. All films were scanned by an Epson Expression 1000XL flatbed scanner (Epson, Suwa, Japan) 24 hr after irradiation. The transmissive scan setting was used in conjunction with settings for 48‐bit color and a 300 dpi resolution. Mean pixel value from the red channel (RC) was determined using an in‐house software(11) from Tiff images. A polynomial fit was used to convert the mean pixel value from the two irradiated film pieces to dose. No off‐axis lateral corrections were used as films were placed within 3.2 cm of the center of the Epson scanner.
Clinac 21ex
Manufactured by Agilent Technologies
Sourced in United States
The Clinac 21EX is a medical linear accelerator manufactured by Agilent Technologies. It is designed to generate high-energy X-rays or electrons for the treatment of various types of cancer. The Clinac 21EX is capable of delivering precise and uniform radiation doses to targeted areas, while minimizing exposure to healthy surrounding tissues.
Automatically generated - may contain errors
Lab products found in correlation
Truebeam, by Agilent Technologies (4 mentions)
Mda mb 231, by Korean Cell Line Bank (3 mentions)
Fetal bovine serum (fbs), by Cytiva (2 mentions)
Penicillin, by Cytiva (2 mentions)
Streptomycin, by Cytiva (2 mentions)
Serum vacutainer, by BD (1 mentions)
Fetal bovine serum (fbs), by Thermo Fisher Scientific (1 mentions)
Rpmi 1640, by Thermo Fisher Scientific (1 mentions)
Portal vision a s500, by Agilent Technologies (1 mentions)
Mda mb 231, by Cytiva (1 mentions)
Zen1600, by Malvern Panalytical (1 mentions)
Tecnai g2 f30, by Thermo Fisher Scientific (1 mentions)
Uv 3600 plus, by Shimadzu (1 mentions)
Fls980, by Edinburgh Instruments (1 mentions)
Gafchromic ebt3 film, by Ashland (1 mentions)
Female c57bl 6 mice, by Orient Bio (1 mentions)
Tomohd system, by Accuray (1 mentions)
Kaleidagraph version 3, by Synergy Software (1 mentions)
Clinac 2100 cd, by Agilent Technologies (1 mentions)
41 protocols using clinac 21ex
1
Gafchromic EBT2 Film Dosimetry Protocol
2
Reporting Linear Accelerator Events in Radiation Oncology
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
The ROQRS:ML system was used to report events occurring on any of four linear accelerators at our institution. All were manufactured by Varian Medical Systems and include a TrueBeam, Trilogy, 23iX RapidArc, and 21EX Clinac. The installation dates, energies, and installed features are listed in Table 1 Over the evaluated time period, the median number of patients on treatment in our clinic was 124, giving a typical workload on each machine of approximately 30 patients per day, operating from 6:30 a.m. to 6:00 p.m., five days per week. The “Key Features” column in Table 1 indicates the types of treatments that can be performed on each machine for the purposes of estimating the typical workload and complexity of daily treatments only; these features do not indicate their sole function within the clinic.
3
Evaluating Metallic Port Influence on Depth Dose
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Clinac 21EX (Varian Medical Systems, Inc., Palo Alto, CA, USA) was used as a radiation source of X-rays, output at either 4 MV or 6 MV. A film was placed inside a solid phantom (Tough Water WE211 Phantom, Kyoto Kagaku Co., Kyoto, Japan) parallel to the beam axis to measure the depth doses. With the same geometry, a metallic port (Magna-Site®, Inamed/Allergan, Santa Barbara, CA, USA; nominal physical density: 8.4 g/cm3) of an archetypal TTE (McGhan Style 133, Inamed/Allergan, Santa Barbara, CA, USA) was installed on the beam axis on the surface of the phantom. The gantry was angled at 0°, the source-to-surface distance was 100 cm, the radiation field size was 10 cm × 10 cm at its isocenter, and the output was 200 monitor units. Radiochromic film (Gafchromic EBT3 dosimetry film, ISP, Inc., Wayne, NJ, USA) was used; this has an extremely small energy dependence and so was considered a suitable choice as a detector for this study [10 (link)]. For the measurements, the metallic port was placed either perpendicularly (down-perpendicular orientation) or parallel (up-parallel orientation) to the beam axis (Fig. 1 ). The relative differences with and without the metallic port were calculated at the peak depth and at depths of 5, 10 and 15 cm. To illustrate changes in the slope of the attenuation curves, the percentage of the depth dose at 10 cm depth (PDD10) was calculated [11 (link)].
4
Photon Irradiation Dosimetry Validation
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
The monolayers on flasks were irradiated with 6MV photons produced by a medical linear accelerator (Varian Clinac 21EX; Varian). Luminescence dosimeters (nanoDOT; Landauer) were used to measure the dose delivered by the Varian linear accelerator. Calibration of the dosimeters was performed using a MicroStar InLight reader (Landauer), and the error was <1% compared with the planned values for the cell lines (hVSMCs and A10 cells) at 2, 4 and 8 Gy.30
5
Fabrication and Irradiation of Gel Dosimeters
6
Bone Marrow Transplantation and LPS Challenge
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Bone marrow transplantation experiments were performed as described previously (20 (link)). Briefly, 8–10-week old recipient mice were irradiated with 6 Megavolt X-rays from a Linear Accelerator (Varian Clinac 21EX) with two (dorsal and ventral) 525-rad (525 cGy) doses. To prepare bone marrow cells for transplantation, femur bones of donor mice were flushed to collect bone marrows, and single cell suspensions were prepared. A total of 8 × 106 cells were injected into the tail vein of lethally irradiated recipient mice. Reconstituted recipient mice were given 0.2% neomycin sulfate dissolved in acidified water for the first 2 weeks post-transplantation. LPS-challenge experiments were performed 8 weeks post bone marrow reconstitution, which has been previously shown to be an optimal period for repopulation of resident alveolar macrophages with donor cells following total body irradiation (21 (link)).
7
Irradiation of SCLC Cell Lines
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
H20 and H446 human SCLC cell lines were purchased from the China Center for Type Culture Collection. All the cell lines were cultured in RPMI 1640 (GIBCO-BRL) medium supplemented with 10% fetal bovine serum (Gibco, Melbourne, Australia), 100 U/ml penicillin and 100 μg/ml of streptomycin in a cell incubator that provided humidified air with 5% CO2 at 37°C. The cells were treated with a gradient dose of 5 Gy using a Varian Clinac 21Ex at 6 Gy/min. To detect the mRNA and methylation status, the cells were collected 24 h after irradiation.
8
Thorax Phantom Portal Imaging and 3D-CT Data
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
The thorax phantom (N‐1 LUNGMAN, Kyoto Kagaku) was modeled as a patient. A water‐equivalent 2 cm φ sphere was inserted into the right lung as a tumor. The original portal image was acquired with 6 MV therapeutic beam of a linac (Clinac 21EX, Varian Medical System). The thorax phantom was irradiated with 5 monitor units. The source to the axis distance (SAD) and source to the EPID distance (SDD) were 1000 and 1400 mm, respectively. The field size was set to 40 cm × 30 cm at the EPID, which has 512 × 384 pixels, the pixel size was 0.784 mm × 0.784 mm and the signals were recorded as a 16‐bit integer.
The 3D‐CT data were obtained by the SPECT‐CT scanner (Symbia T2, Seimens Healthcare) with the reconstruction matrix 512 × 512 × 512 and voxel size of 0.7 mm × 0.7 mm × 1.0 mm.
The 3D‐CT data were obtained by the SPECT‐CT scanner (Symbia T2, Seimens Healthcare) with the reconstruction matrix 512 × 512 × 512 and voxel size of 0.7 mm × 0.7 mm × 1.0 mm.
9
Modeling EPID Dose Distribution Using DOSRZnrc
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Figure 1 shows the geometric arrangement of the EPID (Portal Vision a‐S500 on Clinac 21 EX, Varian Medical System) for the simulation. The EPID was modeled in detail according to the design provided by the manufacturer. It is mainly composed of a copper (Cu) plate, terbium‐doped gadolinium oxysulfide (Gd2O2S:Tb) scintillator and amorphous silicon (a‐Si) photodiodes. The Cu plate filters lower energy photons and electrons; the Cu plate acts as the photons for the electrons converter when high‐energy photons are impinged upon. Then, the scintillator generates fluorescence by electrons from the Cu plate. It is estimated that 99.5% of the total signal is generated within the scintillator.13 Electron trajectories are complicated within the EPID. To that end, the absorbed dose to Gd2O2S:Tb by a photon from the EPID surface was simulated using the DOSRZnrc code,14 and the dose spread functions of photon energy hν and the radial distance from pencil beam r, ΔD(hν, r) were obtained. In the simulation, equally spaced radial bins with Δr = 0.392 mm (1/2 of pixel width) were arranged. The EPID consists of not only the main three layers but also low‐density materials, such as air, paper and foamed body. In order to consider the spread of low‐energy particles within low‐density materials, the cut‐off energies of photons and electrons were set to 10 and 521 keV.
10
Establishing Radiotherapy-Resistant Breast Cancer Cell Line
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
The human breast cancer cell line MDA-MB-231 was obtained from the Korea Cell Line Bank (Seoul, Korea). RT-R MDA-MB-231 cells were established as described by Ko et al. [22 (link)]. Briefly, cells were irradiated with 2 Gy using a 6-MV photon beam that was produced by a linear accelerator (Clinac 21EX, Varian Medical Systems, Inc., Palo Alto, CA, USA) until a final dose of 50 Gy was achieved, which is a commonly used clinical regimen for radiotherapy in patients with breast cancer. RT-R MDA-MB-231 cells were cultured in Roswell Park Memorial Institute (RPMI) 1640 medium supplemented with 10% fetal bovine serum (FBS) (HyClone Laboratories, Logan, UT, USA), 100 IU/mL penicillin, and 10 µg/mL streptomycin (HyClone Laboratories), and then incubated at 37 °C in a humidified atmosphere containing 5% CO2 and 95% air. RT-R MDA-MB-231 cells were used within five passages.
About PubCompare
Our mission is to provide scientists with the largest repository of trustworthy protocols and intelligent analytical tools, thereby offering them extensive information to design robust protocols aimed at minimizing the risk of failures.
We believe that the most crucial aspect is to grant scientists access to a wide range of reliable sources and new useful tools that surpass human capabilities.
However, we trust in allowing scientists to determine how to construct their own protocols based on this information, as they are the experts in their field.
Ready to get started?
Sign up for free.
Registration takes 20 seconds.
Available from any computer
No download required
Revolutionizing how scientists
search and build protocols!