BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic...BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic characteristics including abnormal drug distribution and clearance.Rocuronium exhibits markedly different distribution patterns in obese patients,with conventional weight correction methods inadequately addressing individual muscle mass variations that critically influence drug distribution.AIM To investigate the quantitative relationship between skeletal muscle index(SMI)and rocuronium distribution volume in obese colorectal cancer patients,establish a population pharmacokinetic model,and develop individualized dosing strategies based on muscle mass.METHODS A retrospective cohort study was conducted,including 100 obese patients(body mass index≥30 kg/m^(2))who underwent elective radical colorectal cancer surgery at our hospital from June 2023 to January 2025.Skeletal muscle mass was measured using InBody 260 body composition analyzer and SMI was calculated to assess muscle mass,with male SMI<7.0 kg/m^(2) and female SMI<5.7 kg/m^(2)as diagnostic criteria for sarcopenia.Plasma rocuronium concentrations were detected by liquid chromatography-tandem mass spectrometry/mass spectrometry,and nonlinear mixed-effect modeling was used to establish population pharmacokinetic modeling.Stepwise regression was used to screen covariates,and dosing regimens were optimized through Monte Carlo simulation.The primary endpoint was targeted plasma concentration achievement rate,and the secondary endpoint was postoperative residual muscle relaxation incidence.RESULTS Among 100 patients,35(35.0%)had sarcopenia and 65(65.0%)did not.Patients in the sarcopenia group were older(64.1±9.8 years vs 54.2±10.9 years,P<0.001)and had significantly lower SMI(6.2±0.8 kg/m^(2)vs 8.4±1.2 kg/m^(2),P<0.001).SMI showed strong positive correlation with rocuronium steady-state distribution volume(r=0.718,P<0.001)and moderate negative correlation with clearance(r=-0.502,P<0.001).A two-compartment population pharmacokinetic model was successfully established,with SMI being the most important covariate affecting central compartment distribution volume(△OFV=-41.2,P<0.001).Model validation showed bootstrap successful convergence rate of 92.3%,and 92.1%of observed values fell within prediction intervals in predicted concentration versus predicted concentration.The SMI-based individualized dosing regimen improved target exposure achievement rate from 82.0%in traditional regimen to 93.5%(P=0.009),and reduced postoperative residual muscle relaxation incidence from 13.0%to 3.5%(P=0.018).The sarcopenia group showed the most significant improvement in achievement rate,from 71.4%to 93.8%(P=0.017).CONCLUSION SMI shows strong correlation with rocuronium distribution volume in obese colorectal cancer patients and is a key factor affecting drug distribution.SMI-based individualized dosing strategies can significantly improve target exposure achievement rate and reduce postoperative residual muscle relaxation incidence,providing scientific evidence for precision anesthesia management in obese patients.展开更多
This study introduces a novel concept,biological in vivo three-dimensional(3D)dose distribution verification,aimed at investigating how respiratory motion affects the efficacy of lung cancer radiotherapy,representing ...This study introduces a novel concept,biological in vivo three-dimensional(3D)dose distribution verification,aimed at investigating how respiratory motion affects the efficacy of lung cancer radiotherapy,representing an evolution from the current standard of rigid-body dose distribution verification.A 3D ex vivo biological lung motion simulation device(3D-BioLungEx)was designed to replicate human respiration.A radiotherapy plan of the patient was copied to the porcine lung,which was driven by 3D-BioLungEx to simulate various respiratory patterns that occur during treatment.To ensure anatomical consistency with the patient’s lung structure,during transmission,skin,skeleton,and organs were adjusted according to CT images of the porcine lung.The patient’s radiotherapy plan was then adapted to the porcine lung using the Monaco treatment planning system(TPS).Next,an iterative optimization and scatter inversion-based dose distribution retro-analysis algorithm(IOSI-BLDose)was developed to calculate the dose distribution during treatment.Gamma passing rates were used to quantify discrepancies between this dose distribution and that of the radiotherapy plan.When respiratory conditions were replicated,the passing rate reached up to 93.61%,while irregular breathing dropped it to 70%-90%,primarily due to amplitude changes.However,cycle variations had minimal impact.Compared to conventional rigid-body dose distribution verification,our method provides real-time biological feedback and more effectively captures motion-induced deviations.Accordingly,our biological in vivo 3D dose distribution verification has potential for improving treatment precision and enabling adaptive radiotherapy in clinical practice.展开更多
In this study,the dosimetric characteristics(thickness applicability,preheating time,temperature and humidity dependence,in-batch uniformity,readout reproducibility,dose linearity,self-decay,and electron energy respon...In this study,the dosimetric characteristics(thickness applicability,preheating time,temperature and humidity dependence,in-batch uniformity,readout reproducibility,dose linearity,self-decay,and electron energy response)of engineered polycarbonate films irradiated with an electron beam(0–600 kGy)were investigated using photoluminescence spectroscopy.The results show a linear relationship between photoluminescence intensity and radiation dose when the thickness of the polycarbonate film is 0.3 mm.A higher fluorescence intensity can be obtained by preheating at 60℃ for 180 min before photoluminescence spectrum analysis.As the temperature during spectral testing and the ambient humidity(during and after irradiation)increased,the photoluminescence intensity of the polycarbonate films decreased.The photoluminescence intensity deviation of the polycarbonate films produced within the same batch at 100 kGy is 2.73%.After ten times of repeated excitations and readouts,the coefficients of variation in photoluminescence intensity are less than 8.6%,and the linear correlation coefficient between photoluminescence intensity and irradiation dose is 0.965 in the dose capture range of 20–600 kGy.Within 60 days of irradiation,the photoluminescence intensity of the polycarbonate film decreased to 60%of the initial value.The response of the 0.3 mm polycarbonate films to electron beams with energies exceeding 3.5 MeV does not differ significantly.This comprehensive analysis indicates the potential of polycarbonate films as a high-radiation dose detection material.展开更多
Nitrogen(N)and phosphorus(P)are essential nutrients and can significantly impact primary productivity of the ecosystem causing water environmental problems.However,their cycling mechanisms are not well understood in a...Nitrogen(N)and phosphorus(P)are essential nutrients and can significantly impact primary productivity of the ecosystem causing water environmental problems.However,their cycling mechanisms are not well understood in alpine mountains with climate change.Hence,94 samples of river water were collected from 2018 to 2020 in the headwaters of the Shule River Basin to assess the nutrients spatiotemporal distribution and combined ap-proach of water quality index to assess water quality and potential sources.The findings depict that high nutrient concentrations were found to coincide with snowmelt and glacial meltwater and rainfall recharge periods,while total flux peaked from June to September due to increased runoff.Notably,total nitrogen(TN)concentrations were significantly higher near the town,primarily attributed to the replenishment of nitrate(NO_(3)^(‒)-N)from live-stock manure.The high total P(TP)was near the glacier,which was attributed to the transportation of glacial sediments into the river,and pH was another critical factor.N was the primary nutrient limiting factor for the growth of phytoplankton in river water.Although the migration and transport of nutrients have altered with climate change,river water quality is good in alpine mountains based on an overall evaluation.These findings contribute to enriching nutrient datasets and highlight the importance of water resource management and water quality assessment in sensitive and fragile alpine mountains.展开更多
Ensuring reliable power supply in urban distribution networks is a complex and critical task.To address the increased demand during extreme scenarios,this paper proposes an optimal dispatch strategy that considers the...Ensuring reliable power supply in urban distribution networks is a complex and critical task.To address the increased demand during extreme scenarios,this paper proposes an optimal dispatch strategy that considers the coordination with virtual power plants(VPPs).The proposed strategy improves systemflexibility and responsiveness by optimizing the power adjustment of flexible resources.In the proposed strategy,theGaussian Process Regression(GPR)is firstly employed to determine the adjustable range of aggregated power within the VPP,facilitating an assessment of its potential contribution to power supply support.Then,an optimal dispatch model based on a leader-follower game is developed to maximize the benefits of the VPP and flexible resources while guaranteeing the power balance at the same time.To solve the proposed optimal dispatch model efficiently,the constraints of the problem are reformulated and resolved using the Karush-Kuhn-Tucker(KKT)optimality conditions and linear programming duality theorem.The effectiveness of the strategy is illustrated through a detailed case study.展开更多
In order to explore a dose distribution verification procedure of intensity modulated radiation therapy （IMRT） for nasopharyngeal carcinoma （NPC） and establish its evaluation criteria, we performed 35 two-dimensio...In order to explore a dose distribution verification procedure of intensity modulated radiation therapy （IMRT） for nasopharyngeal carcinoma （NPC） and establish its evaluation criteria, we performed 35 two-dimensional （2D） patient-specific IMRT verifications over the year i006. The percent of pixels passing 7 and the normalized agreement test （NAT） index were mainly used to represent the agreement between the measured and computed dose distributions with three criteria （2%/2 mm, 3%/3 mm and 5%/3 mm） as recommended in the literature. The results were that all cases passed through verifications with three criteria except that the NAT index of one case was beyond the limitation, and the three tolerance levels of 2%/2mm, 3%/3 mm and 5%/3 mm produced similar clinical verification results but led to different percent of pixels passing Y and NAT index. Our data showed that the percent of pixels passing y and the NAT index were complementary to evaluate future IMRT verifications as two significant metrics. Due to the influence of the noise and the trait of the software, we considered an IMRT plan as acceptable in case of the percent ofpixels passing y 〉95% and the NAT index 〈5 with the 5%/3 mm criteria for IMRT patient-specific quality assurance （QA）.展开更多
Rotundic acid(RA),an ursane-type pentacyclic triterpene acid isolated from the dried barks of Ilex rotunda Thunb.(Aquifoliaceae),possesses diverse bioactivities.To further study its pharmacokinetics,a simple and sensi...Rotundic acid(RA),an ursane-type pentacyclic triterpene acid isolated from the dried barks of Ilex rotunda Thunb.(Aquifoliaceae),possesses diverse bioactivities.To further study its pharmacokinetics,a simple and sensitive liquid chromatography with triple quadrupole mass spectrometry(LC-QqQ-MS/MS)method was developed and validated to quantify RA concentration in rat plasma and tissue using etofesalamide as an internal standard(IS).Plasma and tissue samples were subjected to one-step protein precipitation.Chromatographic separation was achieved on a ZORBAX Eclipse XDB-C_(18) column(4.6mm×50mm,5μm)under gradient conditions with eluents of methanol:acetonitrile(1:1,V/V)and 5mM ammonium formate:methanol(9:1,V/V)at 0.5mL/min.Multiple reaction monitoring transitions were performed at m/z 487.30→437.30 for RA and m/z 256.10→227.10 for IS in the negative mode.The developed LC-QqQ-MS/MS method exhibited good linearity(2-500 ng/mL)and was fully validated in accordance with U.S.Food and Drug Administration bioanalytical guidelines.Dose proportionality and bioavailability in rats were determined by comparing pharmacokinetic data after single oral(10,20,and 40mg/kg)and intravenous(10mg/kg)administration of RA.Tissue distribution was studied following oral administration at 20mg/kg.The results showed that the absolute bioavailability of RA after administration at different doses ranged from 16.1%to 19.4%.RA showed good dose proportionality over a dose range of 10-40 mg/kg.RA was rapidly absorbed in a dose-dependent manner and highly distributed in the liver.In conclusion,this study is the first to systematically elucidate the absorption and distribution characteristics of RA in rats,which can provide additional information for further development and evaluation of RA in drug metabolism and pharmacokinetic studies.展开更多
The hydrophobicity of polluted silicone rubber was improved rapidly under plasma jet treatment.It is an important phenomenon of the interaction between the plasma jet and the porous surface,and shows a wide applicatio...The hydrophobicity of polluted silicone rubber was improved rapidly under plasma jet treatment.It is an important phenomenon of the interaction between the plasma jet and the porous surface,and shows a wide application prospect in the power system.In this process,the spatial characteristics and dose of plasma jet are very important.Therefore,the variation of hydrophobicity of polluted silicone rubber under plasma jet treatment was studied,and the spatial characteristics and dose of plasma jet on polluted silicone rubber were also investigated in the work.The results show that the surface property(hydrophilic or hydrophobic)depended on the dose of plasma applied to the surface.The effective treated area was a circle,and the contact angles changed along the radial direction of the circle.This was attributable to the diffusion of plasma bullets on the surface and the distribution of plasma species.The plasma dose could be characterized by the energy density of the plasma applied on the surface.With the increase of plasma dose,the surface contact angles first increased rapidly and then decreased gradually.展开更多
A liquid fueled thorium molten salt reactor(TMSR-LF),one of the Generation IV reactors,was designed by the Shanghai Institute of Applied Physics,Chinese Academy of Sciences.This study uses the‘rt code to calculate th...A liquid fueled thorium molten salt reactor(TMSR-LF),one of the Generation IV reactors,was designed by the Shanghai Institute of Applied Physics,Chinese Academy of Sciences.This study uses the‘rt code to calculate the neutron and gamma dose rate distributions around the reactor.Multiple types of tallies and variance reduction techniques were employed to reduce calculation time and obtain convergent calculation results.Based on the calculation and analysis results,the TMSR-LF1 radiation shield with a 60-cm serpentine concrete layer and a 120-cm ordinary concrete layer is able to meet radiation requirements.The gamma dose rate outside the reactor biological shield was 16.1 mSv h-1;this is higher than the neutron dose rate of 3.71×10^(–2)mSv h^(-1).The maximum thermal neutron flux density outside the reactor biological shield was 1.899103 cm^(-2)s^(-1),which was below the 19105 cm^(-2)s^(-1)limit.展开更多
A few CT-based voxel phantoms were produced to investigate the sensitivity of Monte Carlo simulations of X-ray beam and electron beam to the proportions of elements and the mass densities of the materials used to expr...A few CT-based voxel phantoms were produced to investigate the sensitivity of Monte Carlo simulations of X-ray beam and electron beam to the proportions of elements and the mass densities of the materials used to express the patient’s anatomical structure. The human body can be well outlined by air, lung, adipose, muscle, soft bone and hard bone to calculate the dose distribution with Monte Carlo method. The effects of the calibration curves established by using various CT scanners are not clinically significant based on our investigation. The deviation from the values of cumulative dose volume histogram derived from CT-based voxel phantoms is less than 1% for the given target.展开更多
Objective： We studied the relationship between impact of dose distribution and energy of radioactive ray in teletherapy with contraceptive ring. Methods： The SI Virtual Water Phantom was used to monitor medium of do...Objective： We studied the relationship between impact of dose distribution and energy of radioactive ray in teletherapy with contraceptive ring. Methods： The SI Virtual Water Phantom was used to monitor medium of dose. PTW ionization chamber was used to detect the dose. AP-PA （10 cmx 10 cm） and SAD technique were adopted. Monitoring dose of different locations with different energy of radioactive ray in AP and PA respectively with and without contraceptive ring, repeated 5 times. Results： Dose of with contraceptive ring was lower than that of without contraceptive ring in AP 6 MV- X-ray （P 〈 0.05）, while in PA was no obvious difference （P 〉 0.05）. Dose of except for the center was higher than that of without contraceptive ring in AP and PA 15 MV-X-ray （P 〈 0.05）. For locations, doses of the upper, the left and right were higher than that of the center in AP 6 MV-X-ray （P 〈 0.05）, while in PA was lower （P 〉 0.05）. In AP and PA 15 MV-X-ray, doses of the upper, the left and right was higher than that of the center （P 〈 0.05）. Conclusion： Metallic contraceptive ring would effect the dose distribution of radioactive ray, but influence degree related to locations of contraceptive ring and energy of radioactive ray.展开更多
The risk of pharmacokinetic polyphenols-trace elements interaction may undesirable therapeutic outcomes. We evaluate the long-term use of silibinin, epigallocatechin (ECGC), quercetin and rutin on the absorption and t...The risk of pharmacokinetic polyphenols-trace elements interaction may undesirable therapeutic outcomes. We evaluate the long-term use of silibinin, epigallocatechin (ECGC), quercetin and rutin on the absorption and tissue distribution of zinc, copper and iron after single oral doses in rats. Five groups of rats were either with olive oil as control or with one of the polyphenols silibinin, EPGC, quercetin or rutin, administered orally as oily solutions for 30 days. At day 30, a solution contains sulphate salt of zinc, copper and iron was administered orally;3 hrs later blood samples, tissues of brain, kidney and liver were obtained for evaluation of the elements levels. The results showed that the polyphenols increased both serum and tissue levels of these elements compared with controls. This effect was relatively varied according to the structural differences among flavonoids. In conclusion, long-term use of supraphysiological doses of flavonoids increase absorption of Zn, Cu and Fe and their tissue availability in brain, kidney and liver;this effect seems to be different with variations in structural features.展开更多
Postoperative radiotherapy is a major treatment for patients with maxillary sinus carcinoma. However, the irregular resection cavity poses a technical difficulty for this treatment, causing uneven dose distribution to...Postoperative radiotherapy is a major treatment for patients with maxillary sinus carcinoma. However, the irregular resection cavity poses a technical difficulty for this treatment, causing uneven dose distribution to target volumes. In this study, we evaluated the dose distribution to target volumes and normal tissues in postoperative intensity-modulated radiotherapy (IMRT) after placing a water-filled balloon into the resection cavity. Three postoperative patients with advanced maxillary sinus carcinoma were selected in this trial. Water-filled balloons and supporting dental stents were fabricated according to the size of the maxillary resection cavity. Simulation CT scans were performed with or without water-filled balloons, IMRT treatment plans were established, and dose distribution to target volumes and organs at risk were evaluated. Compared to those in the treatment plan without balloons, the dose (D98) delivered to 98% of the gross tumor volume (GTV) increased by 2.1 Gy (P = 0.009), homogeneity index (HI) improved by 2.3% (P = 0.001), and target volume conformity index (TCI) of 68 Gy increased by 18.5% (P = 0.011) in the plan with balloons. Dosimetry endpoints of normal tissues around target regions in both plans were not significantly different (P > 0.05) except for the optic chiasm. In the plan without balloons, 68 Gy high-dose regions did not entirely cover target volumes in the ethmoid sinus, posteromedial wall of the maxillary sinus, or surgical margin of the hard palate. In contrast, 68 Gy high-dose regions entirely covered the GTV in the plan with balloons. These results suggest that placing a water-filled balloon in the resection cavity for postoperative IMRT of maxillary sinus c arcinoma can reduce low-dose regions and markedly and simultaneously increase dose homogeneity and conformity of target volumes.展开更多
The sorption and phase distribution of 20% ethanol and butanol blended gasoline （E20 and B20） vapours have been examined in soils with varying soil organic matter （SOM） and water contents via laboratory microcosm ...The sorption and phase distribution of 20% ethanol and butanol blended gasoline （E20 and B20） vapours have been examined in soils with varying soil organic matter （SOM） and water contents via laboratory microcosm experiments. The presence of 20% alcohol reduced the sorption of gasoline compounds by soil as well as the mass distribution of the compounds to soil solids. This effect was greater for ethanol than butanol. Compared with the sorption coefficient （Kd） of unblended gasoline compounds, the Kd of E20 gasoline compounds decreased by 54% for pentane, 54% for methylcyclopentane （MCP） and 63% for benzene, while the Kd of B20 gasoline compounds decreased by 39% for pentane, 38% for MCP and 49% for benzene, The retardation factor （R） of E20 gasoline compounds decreased by 53% for pentane, 53% for MCP and 48% for benzene, while the R of B20 gasoline compounds decreased by 39% for pentane, 37% for MCP and 38% for benzene. For all SOM and water contents tested, the Kd and R of all gasoline compounds were in the order of unblended gasoline 〉 B20 〉 E20, indicating that the use of high ethanol volume in gasoline to combat climate change could put the groundwater at greater risk of contamination,展开更多
Introduction: Radiation is indispensable for diagnosis and treatment and is widely used in medicine. This study aimed to determine patients’ knowledge and ability to understand radiation exposure to assess the useful...Introduction: Radiation is indispensable for diagnosis and treatment and is widely used in medicine. This study aimed to determine patients’ knowledge and ability to understand radiation exposure to assess the usefulness of providing information on radiation doses to examinees. Material and Methods: The radiation exposure literacy of mammography examinees was assessed using a new scale consisting of the following five items: “collection of information from various sources”, “selection of information necessary for oneself”, “understanding and communication of information”, “judgment of the reliability of information”, and “ability to plan and act based on information”. We analyzed the relationship of these items with examinees’ attributes and clarified the level of understanding of radiation exposure dose associated with mammography examinations by providing examinees with visual information in the form of color maps. Results: The relationship between “information collection” and several attributes of radiation exposure literacy was strong. In addition, providing visual information on radiation doses using dose distribution maps in mammography examinations could deepen the understanding of radiation doses among examinees. Conclusion: By understanding the radiation exposure literacy of examinees and comparing it with their attributes, it is possible to provide suggestions for developing methods of providing radiation dose information tailored to individual examinees. In addition, improving radiation exposure literacy will enable the development of skills necessary to provide safe medical care to medical examinees.展开更多
Purpose: In radiation therapy, gold nanoparticles (GNPs) are regarded as a promising radiosensitizer candidate. Several studies have revealed a dose enhancement by GNPs in X-ray and even proton irradiation. However, t...Purpose: In radiation therapy, gold nanoparticles (GNPs) are regarded as a promising radiosensitizer candidate. Several studies have revealed a dose enhancement by GNPs in X-ray and even proton irradiation. However, these studies have been limited to the depth direction. The dose distribution in both depth and lateral directions is crucial to evaluate the full radio sensitizing effect. The purpose of this study is to estimate the dose distribution around a GNP in terms of ejected electrons. Methods: The Geant4 Monte Carlo simulation toolkit was used to evaluate the energy deposition of electrons produced by a GNP. A 20 nm diameter spherical GNP was located in a water box and proton beams were incident unidirectionally. The energy deposition and location of produced electrons were tallied by 5 nm width water slabs at a variety of depths behind the GNP. The radial dose distribution was obtained in each slab. Results: The largest radial dose was observed in the slab closest to the GNP. At the slabs deeper than 90 nm, the dose in the radial direction within 10 nm from the beam direction was found to be smaller than that without GNP. This is because the presence of a GNP decreases the dose behind the GNP, forming a dose shadow. The dose enhancement both in depth and lateral directions was shown in surrounding areas. The area of distribution became larger as the absorbed dose decreased. Conclusion: The dose distribution around a GNP was estimated by a simulation study. The dose enhancement was observed in both the lateral and depth directions. This study will enable us to make use of GNPs as a radiosensitizer in proton therapy.展开更多
The radiation therapy is applied on around 50% of the cancer patients. As we know, before implementing a radiation treatment planning system in the clinic, the dose-calculation measurement must be validated using rigo...The radiation therapy is applied on around 50% of the cancer patients. As we know, before implementing a radiation treatment planning system in the clinic, the dose-calculation measurement must be validated using rigorous, clinically relevant criteria [1]. Percent Depth Doses (PDD), Dose Profile (DP), Open Collimator Factor (OCF) etc., are measured for all numbers of square fields for Treatment Planning System XiO, version 4.7, for 6 and 15 MV photons energies and for 15°, 30°, 45°, 60° wedge, which were employed to obtain the profiles in any depth. The measurements were conducted also for different energies of electron beam and TPS calculation algorithms.展开更多
Imatinib is an efficacious anticancer drug with a spectrum of potential antitumour applications limited by poor biodistribution at therapeutic concentrations to the tissues of interest.We assess the pharma-cokinetic a...Imatinib is an efficacious anticancer drug with a spectrum of potential antitumour applications limited by poor biodistribution at therapeutic concentrations to the tissues of interest.We assess the pharma-cokinetic and tissue distribution profile of imatinib in a liposome formulation.Its single dose(6.25 mg·kg-1) in a liposome formulation was administered iv to male mice.Imatinib concentration was measured in plasma,spleen,liver,kidney and brain using a HPLC assay.Non-compartmental pharmacokinetic approach was used to assess the disposition parameters.The plasma disposition profile was biphasic with a plateau-like second phase.The AUC0→∞ was 11.24 μg·h·mL-1,the elimination rate constant(kel) was 0.348 h-1 and the elimination half life(t1/2) was 2.0 h.The mean residence time(MRT) was 2.59 h,VSS was 1.44 L·kg-1 and clearance was 0.56 L·h·kg-1.Liver achieved the highest tissue exposure:CMAX = 18.72 μg·mL-1;AUC0→∞ = 58.18 μg·h·mL-1 and longest t1/2(4.29 h) and MRT(5.31 h).Kidney and spleen AUC0→∞ were 47.98 μg·h·mL-1 and 23.46 μg·h·mL-1,respectively.Half-life was 1.83 h for the kidney and 3.37 h for the spleen.Imatinib penetrated into the brain reaching ～1 μg·g-1.Upon correction by organ blood flow the spleen showed the largest uptake efficiency.Liposomal imatinib presented extensive biodistribution.The drug uptake kinetics showed mechanism differences amongst the tissues.These findings encourage the development of novel imatinib formulations to treat other cancers.展开更多
Aim: This study aims to evaluate the difference between depth data from an intraoral cone and a conventional irradiation tube calculated using a treatment planning system (TPS), and that measured using an intraoral co...Aim: This study aims to evaluate the difference between depth data from an intraoral cone and a conventional irradiation tube calculated using a treatment planning system (TPS), and that measured using an intraoral cone for electron radiotherapy. Background: A TPS is only compatible with conventional irradiation tubes. However, such systems are not suitable for determining dose distributions when a special cone is employed. Materials and Methods: Dose distributions were calculated using the beam data for mounted intraoral cones using a TPS. Then, the dose distribution by field size was calculated for a low-melting-point lead alloy using the beam data for a mounted conventional tube. The calculated data were evaluated against the measured intraoral-cone depth data based on the dose and depth differences. Results: The calculated data for the intraoral cone case did not match the measured data. However, the depth data obtained considering the field size determined for the lead alloy using the conventional tube were close to the measured values for the intraoral cone case. The difference in the depth at which the absorbed dose was 50% of the maximum value of the percentage depth dose was less than ±4 mm for the generalized Gaussian pencil beam convolution algorithm and less than ±1 mm for the electron Monte Carlo algorithm. Conclusion: It was found that the measured and calculated dose distributions were in agreement, especially when then electron Monte Carlo algorithm was used. Thus, the TPS can be employed to determine dose distributions for intraoral cone applications.展开更多
文摘BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic characteristics including abnormal drug distribution and clearance.Rocuronium exhibits markedly different distribution patterns in obese patients,with conventional weight correction methods inadequately addressing individual muscle mass variations that critically influence drug distribution.AIM To investigate the quantitative relationship between skeletal muscle index(SMI)and rocuronium distribution volume in obese colorectal cancer patients,establish a population pharmacokinetic model,and develop individualized dosing strategies based on muscle mass.METHODS A retrospective cohort study was conducted,including 100 obese patients(body mass index≥30 kg/m^(2))who underwent elective radical colorectal cancer surgery at our hospital from June 2023 to January 2025.Skeletal muscle mass was measured using InBody 260 body composition analyzer and SMI was calculated to assess muscle mass,with male SMI<7.0 kg/m^(2) and female SMI<5.7 kg/m^(2)as diagnostic criteria for sarcopenia.Plasma rocuronium concentrations were detected by liquid chromatography-tandem mass spectrometry/mass spectrometry,and nonlinear mixed-effect modeling was used to establish population pharmacokinetic modeling.Stepwise regression was used to screen covariates,and dosing regimens were optimized through Monte Carlo simulation.The primary endpoint was targeted plasma concentration achievement rate,and the secondary endpoint was postoperative residual muscle relaxation incidence.RESULTS Among 100 patients,35(35.0%)had sarcopenia and 65(65.0%)did not.Patients in the sarcopenia group were older(64.1±9.8 years vs 54.2±10.9 years,P<0.001)and had significantly lower SMI(6.2±0.8 kg/m^(2)vs 8.4±1.2 kg/m^(2),P<0.001).SMI showed strong positive correlation with rocuronium steady-state distribution volume(r=0.718,P<0.001)and moderate negative correlation with clearance(r=-0.502,P<0.001).A two-compartment population pharmacokinetic model was successfully established,with SMI being the most important covariate affecting central compartment distribution volume(△OFV=-41.2,P<0.001).Model validation showed bootstrap successful convergence rate of 92.3%,and 92.1%of observed values fell within prediction intervals in predicted concentration versus predicted concentration.The SMI-based individualized dosing regimen improved target exposure achievement rate from 82.0%in traditional regimen to 93.5%(P=0.009),and reduced postoperative residual muscle relaxation incidence from 13.0%to 3.5%(P=0.018).The sarcopenia group showed the most significant improvement in achievement rate,from 71.4%to 93.8%(P=0.017).CONCLUSION SMI shows strong correlation with rocuronium distribution volume in obese colorectal cancer patients and is a key factor affecting drug distribution.SMI-based individualized dosing strategies can significantly improve target exposure achievement rate and reduce postoperative residual muscle relaxation incidence,providing scientific evidence for precision anesthesia management in obese patients.
基金supported by the National Natural Science Foundation of China(No.62371243)National Key Research and Development Program of China(No.2025YFC2427600)+4 种基金the Jiangsu Provincial Key Research and Development Program Social Development Project(No.BE2022720)the Natural Science Foundation of Jiangsu Province(No.BK20231190)Jiangsu Provincial Medical Key Discipline Cultivation Unit of Oncology Therapeutics(Radiotherapy)(No.JSDW202237)Changzhou Social Development Program(Nos.CE20235063 and CJ20244020)Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.JX13614239).
文摘This study introduces a novel concept,biological in vivo three-dimensional(3D)dose distribution verification,aimed at investigating how respiratory motion affects the efficacy of lung cancer radiotherapy,representing an evolution from the current standard of rigid-body dose distribution verification.A 3D ex vivo biological lung motion simulation device(3D-BioLungEx)was designed to replicate human respiration.A radiotherapy plan of the patient was copied to the porcine lung,which was driven by 3D-BioLungEx to simulate various respiratory patterns that occur during treatment.To ensure anatomical consistency with the patient’s lung structure,during transmission,skin,skeleton,and organs were adjusted according to CT images of the porcine lung.The patient’s radiotherapy plan was then adapted to the porcine lung using the Monaco treatment planning system(TPS).Next,an iterative optimization and scatter inversion-based dose distribution retro-analysis algorithm(IOSI-BLDose)was developed to calculate the dose distribution during treatment.Gamma passing rates were used to quantify discrepancies between this dose distribution and that of the radiotherapy plan.When respiratory conditions were replicated,the passing rate reached up to 93.61%,while irregular breathing dropped it to 70%-90%,primarily due to amplitude changes.However,cycle variations had minimal impact.Compared to conventional rigid-body dose distribution verification,our method provides real-time biological feedback and more effectively captures motion-induced deviations.Accordingly,our biological in vivo 3D dose distribution verification has potential for improving treatment precision and enabling adaptive radiotherapy in clinical practice.
基金supported by the National Natural Science Foundation of China(No.12305385)Key Projects of Scientific Research of the Hunan Provincial Department of Education(22A0310)the Research Startup Project of University of South China(220XQD025).
文摘In this study,the dosimetric characteristics(thickness applicability,preheating time,temperature and humidity dependence,in-batch uniformity,readout reproducibility,dose linearity,self-decay,and electron energy response)of engineered polycarbonate films irradiated with an electron beam(0–600 kGy)were investigated using photoluminescence spectroscopy.The results show a linear relationship between photoluminescence intensity and radiation dose when the thickness of the polycarbonate film is 0.3 mm.A higher fluorescence intensity can be obtained by preheating at 60℃ for 180 min before photoluminescence spectrum analysis.As the temperature during spectral testing and the ambient humidity(during and after irradiation)increased,the photoluminescence intensity of the polycarbonate films decreased.The photoluminescence intensity deviation of the polycarbonate films produced within the same batch at 100 kGy is 2.73%.After ten times of repeated excitations and readouts,the coefficients of variation in photoluminescence intensity are less than 8.6%,and the linear correlation coefficient between photoluminescence intensity and irradiation dose is 0.965 in the dose capture range of 20–600 kGy.Within 60 days of irradiation,the photoluminescence intensity of the polycarbonate film decreased to 60%of the initial value.The response of the 0.3 mm polycarbonate films to electron beams with energies exceeding 3.5 MeV does not differ significantly.This comprehensive analysis indicates the potential of polycarbonate films as a high-radiation dose detection material.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(No.2019QZKK0208)the National Natural Science Foundation of China(Nos.42171148 and 42330512)the Key R&D Project from the Science and Technology Department of Tibet(No.XZ202501ZY0030).
文摘Nitrogen(N)and phosphorus(P)are essential nutrients and can significantly impact primary productivity of the ecosystem causing water environmental problems.However,their cycling mechanisms are not well understood in alpine mountains with climate change.Hence,94 samples of river water were collected from 2018 to 2020 in the headwaters of the Shule River Basin to assess the nutrients spatiotemporal distribution and combined ap-proach of water quality index to assess water quality and potential sources.The findings depict that high nutrient concentrations were found to coincide with snowmelt and glacial meltwater and rainfall recharge periods,while total flux peaked from June to September due to increased runoff.Notably,total nitrogen(TN)concentrations were significantly higher near the town,primarily attributed to the replenishment of nitrate(NO_(3)^(‒)-N)from live-stock manure.The high total P(TP)was near the glacier,which was attributed to the transportation of glacial sediments into the river,and pH was another critical factor.N was the primary nutrient limiting factor for the growth of phytoplankton in river water.Although the migration and transport of nutrients have altered with climate change,river water quality is good in alpine mountains based on an overall evaluation.These findings contribute to enriching nutrient datasets and highlight the importance of water resource management and water quality assessment in sensitive and fragile alpine mountains.
基金supported by the Science and Technology Project of Sichuan Electric Power Company“Power Supply Guarantee Strategy for Urban Distribution Networks Considering Coordination with Virtual Power Plant during Extreme Weather Event”(No.521920230003).
文摘Ensuring reliable power supply in urban distribution networks is a complex and critical task.To address the increased demand during extreme scenarios,this paper proposes an optimal dispatch strategy that considers the coordination with virtual power plants(VPPs).The proposed strategy improves systemflexibility and responsiveness by optimizing the power adjustment of flexible resources.In the proposed strategy,theGaussian Process Regression(GPR)is firstly employed to determine the adjustable range of aggregated power within the VPP,facilitating an assessment of its potential contribution to power supply support.Then,an optimal dispatch model based on a leader-follower game is developed to maximize the benefits of the VPP and flexible resources while guaranteeing the power balance at the same time.To solve the proposed optimal dispatch model efficiently,the constraints of the problem are reformulated and resolved using the Karush-Kuhn-Tucker(KKT)optimality conditions and linear programming duality theorem.The effectiveness of the strategy is illustrated through a detailed case study.
文摘In order to explore a dose distribution verification procedure of intensity modulated radiation therapy （IMRT） for nasopharyngeal carcinoma （NPC） and establish its evaluation criteria, we performed 35 two-dimensional （2D） patient-specific IMRT verifications over the year i006. The percent of pixels passing 7 and the normalized agreement test （NAT） index were mainly used to represent the agreement between the measured and computed dose distributions with three criteria （2%/2 mm, 3%/3 mm and 5%/3 mm） as recommended in the literature. The results were that all cases passed through verifications with three criteria except that the NAT index of one case was beyond the limitation, and the three tolerance levels of 2%/2mm, 3%/3 mm and 5%/3 mm produced similar clinical verification results but led to different percent of pixels passing Y and NAT index. Our data showed that the percent of pixels passing y and the NAT index were complementary to evaluate future IMRT verifications as two significant metrics. Due to the influence of the noise and the trait of the software, we considered an IMRT plan as acceptable in case of the percent ofpixels passing y 〉95% and the NAT index 〈5 with the 5%/3 mm criteria for IMRT patient-specific quality assurance （QA）.
基金supported by CAMS Innovation Fund for Medical Sciences(Grant No.:2019-I2M-5e020)the National Natural Science Foundation of China(Grant No.:81503154)the National Major Scientific and Technological Special Project for Significant New Drugs Development(Grant No.:2017ZX09101002-001-005).
文摘Rotundic acid(RA),an ursane-type pentacyclic triterpene acid isolated from the dried barks of Ilex rotunda Thunb.(Aquifoliaceae),possesses diverse bioactivities.To further study its pharmacokinetics,a simple and sensitive liquid chromatography with triple quadrupole mass spectrometry(LC-QqQ-MS/MS)method was developed and validated to quantify RA concentration in rat plasma and tissue using etofesalamide as an internal standard(IS).Plasma and tissue samples were subjected to one-step protein precipitation.Chromatographic separation was achieved on a ZORBAX Eclipse XDB-C_(18) column(4.6mm×50mm,5μm)under gradient conditions with eluents of methanol:acetonitrile(1:1,V/V)and 5mM ammonium formate:methanol(9:1,V/V)at 0.5mL/min.Multiple reaction monitoring transitions were performed at m/z 487.30→437.30 for RA and m/z 256.10→227.10 for IS in the negative mode.The developed LC-QqQ-MS/MS method exhibited good linearity(2-500 ng/mL)and was fully validated in accordance with U.S.Food and Drug Administration bioanalytical guidelines.Dose proportionality and bioavailability in rats were determined by comparing pharmacokinetic data after single oral(10,20,and 40mg/kg)and intravenous(10mg/kg)administration of RA.Tissue distribution was studied following oral administration at 20mg/kg.The results showed that the absolute bioavailability of RA after administration at different doses ranged from 16.1%to 19.4%.RA showed good dose proportionality over a dose range of 10-40 mg/kg.RA was rapidly absorbed in a dose-dependent manner and highly distributed in the liver.In conclusion,this study is the first to systematically elucidate the absorption and distribution characteristics of RA in rats,which can provide additional information for further development and evaluation of RA in drug metabolism and pharmacokinetic studies.
基金supported by the Intergovernmental International Cooperation in Science and Technology Innovation Program(No.2019YFE0115600)National Natural Science Foundation of China(No.52177152)Science,Technology and Innovation Commission of Shenzhen Municipality(No.JCYJ20180508152057527)。
文摘The hydrophobicity of polluted silicone rubber was improved rapidly under plasma jet treatment.It is an important phenomenon of the interaction between the plasma jet and the porous surface,and shows a wide application prospect in the power system.In this process,the spatial characteristics and dose of plasma jet are very important.Therefore,the variation of hydrophobicity of polluted silicone rubber under plasma jet treatment was studied,and the spatial characteristics and dose of plasma jet on polluted silicone rubber were also investigated in the work.The results show that the surface property(hydrophilic or hydrophobic)depended on the dose of plasma applied to the surface.The effective treated area was a circle,and the contact angles changed along the radial direction of the circle.This was attributable to the diffusion of plasma bullets on the surface and the distribution of plasma species.The plasma dose could be characterized by the energy density of the plasma applied on the surface.With the increase of plasma dose,the surface contact angles first increased rapidly and then decreased gradually.
基金the Chinese Academy of Sciences TMSR Strategic Pioneer Science and Technology Project(No.XDA02010000).
文摘A liquid fueled thorium molten salt reactor(TMSR-LF),one of the Generation IV reactors,was designed by the Shanghai Institute of Applied Physics,Chinese Academy of Sciences.This study uses the‘rt code to calculate the neutron and gamma dose rate distributions around the reactor.Multiple types of tallies and variance reduction techniques were employed to reduce calculation time and obtain convergent calculation results.Based on the calculation and analysis results,the TMSR-LF1 radiation shield with a 60-cm serpentine concrete layer and a 120-cm ordinary concrete layer is able to meet radiation requirements.The gamma dose rate outside the reactor biological shield was 16.1 mSv h-1;this is higher than the neutron dose rate of 3.71×10^(–2)mSv h^(-1).The maximum thermal neutron flux density outside the reactor biological shield was 1.899103 cm^(-2)s^(-1),which was below the 19105 cm^(-2)s^(-1)limit.
基金The project supported by the An Hui Natural Science Foundation (No. 01043601)
文摘A few CT-based voxel phantoms were produced to investigate the sensitivity of Monte Carlo simulations of X-ray beam and electron beam to the proportions of elements and the mass densities of the materials used to express the patient’s anatomical structure. The human body can be well outlined by air, lung, adipose, muscle, soft bone and hard bone to calculate the dose distribution with Monte Carlo method. The effects of the calibration curves established by using various CT scanners are not clinically significant based on our investigation. The deviation from the values of cumulative dose volume histogram derived from CT-based voxel phantoms is less than 1% for the given target.
文摘Objective： We studied the relationship between impact of dose distribution and energy of radioactive ray in teletherapy with contraceptive ring. Methods： The SI Virtual Water Phantom was used to monitor medium of dose. PTW ionization chamber was used to detect the dose. AP-PA （10 cmx 10 cm） and SAD technique were adopted. Monitoring dose of different locations with different energy of radioactive ray in AP and PA respectively with and without contraceptive ring, repeated 5 times. Results： Dose of with contraceptive ring was lower than that of without contraceptive ring in AP 6 MV- X-ray （P 〈 0.05）, while in PA was no obvious difference （P 〉 0.05）. Dose of except for the center was higher than that of without contraceptive ring in AP and PA 15 MV-X-ray （P 〈 0.05）. For locations, doses of the upper, the left and right were higher than that of the center in AP 6 MV-X-ray （P 〈 0.05）, while in PA was lower （P 〉 0.05）. In AP and PA 15 MV-X-ray, doses of the upper, the left and right was higher than that of the center （P 〈 0.05）. Conclusion： Metallic contraceptive ring would effect the dose distribution of radioactive ray, but influence degree related to locations of contraceptive ring and energy of radioactive ray.
文摘The risk of pharmacokinetic polyphenols-trace elements interaction may undesirable therapeutic outcomes. We evaluate the long-term use of silibinin, epigallocatechin (ECGC), quercetin and rutin on the absorption and tissue distribution of zinc, copper and iron after single oral doses in rats. Five groups of rats were either with olive oil as control or with one of the polyphenols silibinin, EPGC, quercetin or rutin, administered orally as oily solutions for 30 days. At day 30, a solution contains sulphate salt of zinc, copper and iron was administered orally;3 hrs later blood samples, tissues of brain, kidney and liver were obtained for evaluation of the elements levels. The results showed that the polyphenols increased both serum and tissue levels of these elements compared with controls. This effect was relatively varied according to the structural differences among flavonoids. In conclusion, long-term use of supraphysiological doses of flavonoids increase absorption of Zn, Cu and Fe and their tissue availability in brain, kidney and liver;this effect seems to be different with variations in structural features.
文摘Postoperative radiotherapy is a major treatment for patients with maxillary sinus carcinoma. However, the irregular resection cavity poses a technical difficulty for this treatment, causing uneven dose distribution to target volumes. In this study, we evaluated the dose distribution to target volumes and normal tissues in postoperative intensity-modulated radiotherapy (IMRT) after placing a water-filled balloon into the resection cavity. Three postoperative patients with advanced maxillary sinus carcinoma were selected in this trial. Water-filled balloons and supporting dental stents were fabricated according to the size of the maxillary resection cavity. Simulation CT scans were performed with or without water-filled balloons, IMRT treatment plans were established, and dose distribution to target volumes and organs at risk were evaluated. Compared to those in the treatment plan without balloons, the dose (D98) delivered to 98% of the gross tumor volume (GTV) increased by 2.1 Gy (P = 0.009), homogeneity index (HI) improved by 2.3% (P = 0.001), and target volume conformity index (TCI) of 68 Gy increased by 18.5% (P = 0.011) in the plan with balloons. Dosimetry endpoints of normal tissues around target regions in both plans were not significantly different (P > 0.05) except for the optic chiasm. In the plan without balloons, 68 Gy high-dose regions did not entirely cover target volumes in the ethmoid sinus, posteromedial wall of the maxillary sinus, or surgical margin of the hard palate. In contrast, 68 Gy high-dose regions entirely covered the GTV in the plan with balloons. These results suggest that placing a water-filled balloon in the resection cavity for postoperative IMRT of maxillary sinus c arcinoma can reduce low-dose regions and markedly and simultaneously increase dose homogeneity and conformity of target volumes.
文摘The sorption and phase distribution of 20% ethanol and butanol blended gasoline （E20 and B20） vapours have been examined in soils with varying soil organic matter （SOM） and water contents via laboratory microcosm experiments. The presence of 20% alcohol reduced the sorption of gasoline compounds by soil as well as the mass distribution of the compounds to soil solids. This effect was greater for ethanol than butanol. Compared with the sorption coefficient （Kd） of unblended gasoline compounds, the Kd of E20 gasoline compounds decreased by 54% for pentane, 54% for methylcyclopentane （MCP） and 63% for benzene, while the Kd of B20 gasoline compounds decreased by 39% for pentane, 38% for MCP and 49% for benzene, The retardation factor （R） of E20 gasoline compounds decreased by 53% for pentane, 53% for MCP and 48% for benzene, while the R of B20 gasoline compounds decreased by 39% for pentane, 37% for MCP and 38% for benzene. For all SOM and water contents tested, the Kd and R of all gasoline compounds were in the order of unblended gasoline 〉 B20 〉 E20, indicating that the use of high ethanol volume in gasoline to combat climate change could put the groundwater at greater risk of contamination,
文摘Introduction: Radiation is indispensable for diagnosis and treatment and is widely used in medicine. This study aimed to determine patients’ knowledge and ability to understand radiation exposure to assess the usefulness of providing information on radiation doses to examinees. Material and Methods: The radiation exposure literacy of mammography examinees was assessed using a new scale consisting of the following five items: “collection of information from various sources”, “selection of information necessary for oneself”, “understanding and communication of information”, “judgment of the reliability of information”, and “ability to plan and act based on information”. We analyzed the relationship of these items with examinees’ attributes and clarified the level of understanding of radiation exposure dose associated with mammography examinations by providing examinees with visual information in the form of color maps. Results: The relationship between “information collection” and several attributes of radiation exposure literacy was strong. In addition, providing visual information on radiation doses using dose distribution maps in mammography examinations could deepen the understanding of radiation doses among examinees. Conclusion: By understanding the radiation exposure literacy of examinees and comparing it with their attributes, it is possible to provide suggestions for developing methods of providing radiation dose information tailored to individual examinees. In addition, improving radiation exposure literacy will enable the development of skills necessary to provide safe medical care to medical examinees.
文摘Purpose: In radiation therapy, gold nanoparticles (GNPs) are regarded as a promising radiosensitizer candidate. Several studies have revealed a dose enhancement by GNPs in X-ray and even proton irradiation. However, these studies have been limited to the depth direction. The dose distribution in both depth and lateral directions is crucial to evaluate the full radio sensitizing effect. The purpose of this study is to estimate the dose distribution around a GNP in terms of ejected electrons. Methods: The Geant4 Monte Carlo simulation toolkit was used to evaluate the energy deposition of electrons produced by a GNP. A 20 nm diameter spherical GNP was located in a water box and proton beams were incident unidirectionally. The energy deposition and location of produced electrons were tallied by 5 nm width water slabs at a variety of depths behind the GNP. The radial dose distribution was obtained in each slab. Results: The largest radial dose was observed in the slab closest to the GNP. At the slabs deeper than 90 nm, the dose in the radial direction within 10 nm from the beam direction was found to be smaller than that without GNP. This is because the presence of a GNP decreases the dose behind the GNP, forming a dose shadow. The dose enhancement both in depth and lateral directions was shown in surrounding areas. The area of distribution became larger as the absorbed dose decreased. Conclusion: The dose distribution around a GNP was estimated by a simulation study. The dose enhancement was observed in both the lateral and depth directions. This study will enable us to make use of GNPs as a radiosensitizer in proton therapy.
文摘The radiation therapy is applied on around 50% of the cancer patients. As we know, before implementing a radiation treatment planning system in the clinic, the dose-calculation measurement must be validated using rigorous, clinically relevant criteria [1]. Percent Depth Doses (PDD), Dose Profile (DP), Open Collimator Factor (OCF) etc., are measured for all numbers of square fields for Treatment Planning System XiO, version 4.7, for 6 and 15 MV photons energies and for 15°, 30°, 45°, 60° wedge, which were employed to obtain the profiles in any depth. The measurements were conducted also for different energies of electron beam and TPS calculation algorithms.
基金the International Medical University(IMU)for financial support:Grant#B0104RES(05)2007.
文摘Imatinib is an efficacious anticancer drug with a spectrum of potential antitumour applications limited by poor biodistribution at therapeutic concentrations to the tissues of interest.We assess the pharma-cokinetic and tissue distribution profile of imatinib in a liposome formulation.Its single dose(6.25 mg·kg-1) in a liposome formulation was administered iv to male mice.Imatinib concentration was measured in plasma,spleen,liver,kidney and brain using a HPLC assay.Non-compartmental pharmacokinetic approach was used to assess the disposition parameters.The plasma disposition profile was biphasic with a plateau-like second phase.The AUC0→∞ was 11.24 μg·h·mL-1,the elimination rate constant(kel) was 0.348 h-1 and the elimination half life(t1/2) was 2.0 h.The mean residence time(MRT) was 2.59 h,VSS was 1.44 L·kg-1 and clearance was 0.56 L·h·kg-1.Liver achieved the highest tissue exposure:CMAX = 18.72 μg·mL-1;AUC0→∞ = 58.18 μg·h·mL-1 and longest t1/2(4.29 h) and MRT(5.31 h).Kidney and spleen AUC0→∞ were 47.98 μg·h·mL-1 and 23.46 μg·h·mL-1,respectively.Half-life was 1.83 h for the kidney and 3.37 h for the spleen.Imatinib penetrated into the brain reaching ～1 μg·g-1.Upon correction by organ blood flow the spleen showed the largest uptake efficiency.Liposomal imatinib presented extensive biodistribution.The drug uptake kinetics showed mechanism differences amongst the tissues.These findings encourage the development of novel imatinib formulations to treat other cancers.
文摘Aim: This study aims to evaluate the difference between depth data from an intraoral cone and a conventional irradiation tube calculated using a treatment planning system (TPS), and that measured using an intraoral cone for electron radiotherapy. Background: A TPS is only compatible with conventional irradiation tubes. However, such systems are not suitable for determining dose distributions when a special cone is employed. Materials and Methods: Dose distributions were calculated using the beam data for mounted intraoral cones using a TPS. Then, the dose distribution by field size was calculated for a low-melting-point lead alloy using the beam data for a mounted conventional tube. The calculated data were evaluated against the measured intraoral-cone depth data based on the dose and depth differences. Results: The calculated data for the intraoral cone case did not match the measured data. However, the depth data obtained considering the field size determined for the lead alloy using the conventional tube were close to the measured values for the intraoral cone case. The difference in the depth at which the absorbed dose was 50% of the maximum value of the percentage depth dose was less than ±4 mm for the generalized Gaussian pencil beam convolution algorithm and less than ±1 mm for the electron Monte Carlo algorithm. Conclusion: It was found that the measured and calculated dose distributions were in agreement, especially when then electron Monte Carlo algorithm was used. Thus, the TPS can be employed to determine dose distributions for intraoral cone applications.
