Background: We aim to present our linear accelerator-based workflow for pancreatic stereotactic ablative radiotherapy (SABR) in order to address the following issues: intrafractional organ motion management, Cone Beam CT (CBCT) image quality, residual errors with dosimetric consequences, treatment time, and clinical results. Methods: Between 2016 and 2021, 14 patients with locally advanced pancreatic cancer were treated with induction chemotherapy and SABR using volumetric modulated arc therapy (VMAT). Internal target volume (ITV) concept (5), phase-gated (4), or breath hold (5) techniques were used. Treatment was verified by CBCT before and after irradiation, while tumor motion was monitored and controlled by kV triggered imaging and beam hold using peritumoral surgical clips. Beam interruptions and treatment time were recorded. The CBCT image quality was scored and supplemented by an agreement analysis (Krippendorff’s-α) of breath-hold CBCT images to determine the position of OARs relative to the planning risk volumes (PRV). Residual errors and their dosimetry impact were also calculated. Progression free (PFS) and overall survival (OS) were assessed by the Kaplan-Meier analysis with acute and late toxicity reporting (CTCAEv4). Results: On average, beams were interrupted once (range: 0–3) per treatment session on triggered imaging. The total median treatment time was 16.7 ± 10.8 min, significantly less for breath-hold vs. phase-gated sessions (18.8 ± 6.2 vs. 26.5 ± 13.4, p < 0.001). The best image quality was achieved by breath hold CBCT. The Krippendorff’s-α test showed a strong agreement among five radiation therapists (mean K-α value: 0.8 (97.5%). The mean residual errors were <0.2 cm in each direction resulting in an average difference of <2% in dosimetry for OAR and target volume. Two patients received offline adaptation. The median OS/PFS after induction chemotherapy and SABR was 20/12 months and 15/8 months. No Gr. ≥2 acute/late RT-related toxicity was noted. Conclusion: Linear accelerator based pancreatic SABR with the combination of CBCT and triggered imaging + beam hold is feasible. Peritumoral fiducials improve utility while breath-hold CBCT provides the best image quality at a reasonable treatment time with offline adaptation possibilities. In well-selected cases, it can be an effective alternative in clinics where CBCT/MRI-guided online adaptive workflow is not available.

PurposeTo investigate the added value of 6-(18F]-fluoro-L-3,4-dihydroxyphenylalanine (FDOPA) PET to radiotherapy planning in glioblastoma multiforme (GBM).MethodsFrom September 2017 to December 2020, 17 patients with GBM received external beam radiotherapy up to 60 Gy with concurrent and adjuvant temozolamide. Target volume delineations followed the European guideline with a 2-cm safety margin clinical target volume (CTV) around the contrast-enhanced lesion+resection cavity on MRI gross tumor volume (GTV). All patients had FDOPA hybrid PET/MRI followed by PET/CT before radiotherapy planning. PET segmentation followed international recommendation: T/N 1.7 (BTV1.7) and T/N 2 (BTV2.0) SUV thresholds were used for biological target volume (BTV) delineation. For GTV-BTVs agreements, 95% of the Hausdorff distance (HD95%) from GTV to the BTVs were calculated, additionally, BTV portions outside of the GTV and coverage by the 95% isodose contours were also determined. In case of recurrence, the latest MR images were co-registered to planning CT to evaluate its location relative to BTVs and 95% isodose contours.ResultsAverage (range) GTV, BTV1.7, and BTV2.0 were 46.58 (6–182.5), 68.68 (9.6–204.1), 42.89 (3.8–147.6) cm3, respectively. HD95% from GTV were 15.5 mm (7.9–30.7 mm) and 10.5 mm (4.3–21.4 mm) for BTV1.7 and BTV2.0, respectively. Based on volumetric assessment, 58.8% (28–100%) of BTV1.7 and 45.7% of BTV2.0 (14-100%) were outside of the standard GTV, still all BTVs were encompassed by the 95% dose. All recurrences were confirmed by follow-up imaging, all occurred within PTV, with an additional outfield recurrence in a single case, which was not DOPA-positive at the beginning of treatment. Good correlation was found between the mean and median values of PET/CT and PET/MRI segmented volumes relative to corresponding brain-accumulated enhancement (r = 0.75; r = 0.72).Conclusion18FFDOPA PET resulted in substantial larger tumor volumes compared to MRI; however, its added value is unclear as vast majority of recurrences occurred within the prescribed dose level. Use of PET/CT signals proved to be feasible in the absence of direct segmentation possibilities of PET/MR in TPS. The added value of 18FFDOPA may be better exploited in the context of integrated dose escalation.

Purpose: The aim of our study was to explore the burnout rate of radiographers working in oncology patient care. Materials and methods: Our cross-sectional, targeted non-random sampled research was carried out from June 2018 to September 2018. We used the Maslach Burnout Inventory supplemented with our own questionnaire for online data collection. In addition to demographic aspects, we collected data about job characteristics to examine predictors of burnout. Statistical analysis was performed using descriptive statistics, two-sampled t-test, analysis of variance, Mann-Whitney test and Kruskal-Wallis test were used at 95% confidence level (p=0.05). Results: We analyzed the data of 72 radiographers working in oncology patient care (n=72) and 332 radiographers working in other fields of patient care (n=332). Radiographers working in oncology patient care were characterized by a significantly increased value of emotional exhaustion (p=0.001). Respondents who were single, provided monthly on-call duty and held university degree showed depersonalization (p=0.001). The presence of a secondary job, working more than 40 hours of work per week and active participation in on-call duty services had a negative effect on emotional exhaustion (p=0.001). Respondents with more than one child in their household showed a significantly better value of personal accomplishment (p=0.001). The subjective assessesment of poor financial status had negative effect on all three dimensions of burnout (p=0.001). Conclusion: The mean values of the emotional exhaustion of radiograhers working in oncology patient care increased significantly. The observed elevated value of personal accomplishment shows a sign of positive feedback coming from the patients towards the radiographer.

Introduction and aim: In case of imaging modalities using ionizing radiation, radiation exposure of the patients is a vital issue. It is important to survey the various dose-reducing techniques to achieve optimal radiation protection while keeping image quality on an optimal level. Method: We reprocessed 105 patients' data prospectively between February and April 2017. The determination of the radiation dose was based on the effective dose, calculated by multiplying the dose-length product (DLP) and dose-conversation coefficient. In case of image quality we used signal-to-noise ratio (SNR) based on manual segmentation of region of interest (ROI). For statistical analysis, one sample t-test and Wilcoxon signed rank test were used. Results: Using iterative reconstruction, the effective dose was significantly lower (p<0.001) in both native and contrast-enhanced abdominal, contrast-enhanced chest CT scans and in the case of the total effective dose. At native and contrast-enhanced abdominal CT scans, the noise content of the images showed significantly lower (p<0.001) values for iterative reconstruction images. At contrast-enhanced chest CT scans there was no significant difference between the noise content of the images (p>0.05). Conclusion: Using iterative reconstruction, it was possible to achieve significant dose reduction. Since the noise content of the images was not significantly higher using the iterative reconstruction compared to the filtered back projection, further dose reduction can be achievable while preserving the optimal quality of the images.

Our aim was to present our treatment and verification protocols of linear accelerator-based lung and abdominal stereotactic ablative radiotherapy (SABR). During our treatments both the volumetric imaging (3D/4D CBCT/CT) and triggered kV intrafractional tumor motion control could be combined allowing a full control on the whole workflow. The most optimal kV directions from which the tumor is well detectable were defined. Tumor movements measured on cine MRI in treatment position correlated well with the ones on 4D CBCT, thus cine MRI is considered an excellent device to pre-select the appropriate image/treatment verification SABR protocol. In abdominal targets implanted markers and cine MRI are preferred due to limited image quality of CBCT with the current version. In selected lung SABR cases (≥8mm motion) the dose delivery of organs at risk (lungs - GTV, chest wall) could be reduced compared to free breathing conditions, however, the treatment time is at least two-folds higher.

Absztrakt: Bevezetes es celkitűzes: Az ionizalo sugarzast hasznalo keresztmetszeti kepalkoto modalitasok alkalmazasa soran kiemelt szerepe van a pacienseket erő sugardozis mennyisegenek. A betegeket erő sugarterheles csokkentesere fokuszalva fontos felmerni a kulonboző doziscsokkentő technikak adta lehetősegeket a sugarvedelem optimalis megvalositasa celjabol a kepminőseg minel magasabb szinten tartasa mellett. Modszer: Kutatasunk soran az intezetunkben hasznalt iterativ keprekonstrukciot (SAFIRE) es a szűrt visszavetiteses rekonstrukciot (FBP) alkalmazo CT-berendezesek sugarterheleset es kepminőseget hasonlitottuk ossze. Vizsgalatunkban prospektiv modon 2017. februar–aprilis intervallumban 105 beteg kepanyagaval dolgoztunk. A CT-vizsgalatok soran a beteget erő effektiv dozis kerult meghatarozasra a dozis-hossz szorzat (DLP) es a doziskonverzios egyutthato szorzatakent. A kepminőseg ertekelesehez manualis terulet kijeloles (ROI-) alapu adatfelvetelt kovetően jel-zaj aranyt (SNR) szamoltunk. A statisztikai elemzest egymintas t-probaval es Wilcoxon-teszttel vegeztuk el. Eredmenyek: Az effektiv dozis iterativ rekonstrukciot alkalmazva szignifikansan alacsonyabb (p<0,001) volt nativ es kontrasztanyagos hasi, illetve kontrasztanyagos mellkasi CT-vizsgalat eseten, tovabba a betegeket ert osszes effektiv dozis tekinteteben is. A felvetelek zajtartalma nativ es kontrasztanyagos hasi CT-vizsgalat soran szignifikansan alacsonyabb (p<0,001) ertekeket mutatott az iterativ rekonstrukcioval keszult kepek eseten. A kontrasztanyagos mellkasi CT-vizsgalatok soran szignifikans elteres nem mutatkozott a ketfele eljarassal keszult kepek zajtartalma kozott (p>0,05). Kovetkeztetes: Az ismetelt CT-vizsgalaton atesett betegek koreben szignifikans doziscsokkentes valt lehetőve az iterativ keprekonstrukcio alkalmazasaval, a kepminőseg megtartasa mellett. A kepek zajtartalma egy regio vizsgalatanal sem volt szignifikansan magasabb az iterativ rekonstrukcio alkalmazasakor a szűrt visszavetiteses rekonstrukciohoz kepest, igy felmerul a tovabbi doziscsokkentes lehetősege optimalis kepminőseg megőrzese mellett. Orv Hetil. 2019; 160(35): 1387–1394. | Abstract: Introduction and aim: In case of imaging modalities using ionizing radiation, radiation exposure of the patients is a vital issue. It is important to survey the various dose-reducing techniques to achieve optimal radiation protection while keeping image quality on an optimal level. Method: We reprocessed 105 patients’ data prospectively between February and April 2017. The determination of the radiation dose was based on the effective dose, calculated by multiplying the dose-length product (DLP) and dose-conversation coefficient. In case of image quality we used signal-to-noise ratio (SNR) based on manual segmentation of region of interest (ROI). For statistical analysis, one sample t-test and Wilcoxon signed rank test were used. Results: Using iterative reconstruction, the effective dose was significantly lower (p<0.001) in both native and contrast-enhanced abdominal, contrast-enhanced chest CT scans and in the case of the total effective dose. At native and contrast-enhanced abdominal CT scans, the noise content of the images showed significantly lower (p<0.001) values for iterative reconstruction images. At contrast-enhanced chest CT scans there was no significant difference between the noise content of the images (p>0.05). Conclusion: Using iterative reconstruction, it was possible to achieve significant dose reduction. Since the noise content of the images was not significantly higher using the iterative reconstruction compared to the filtered back projection, further dose reduction can be achievable while preserving the optimal quality of the images. Orv Hetil. 2019; 160(35): 1387–1394.

Abstract: Introduction and aim: In case of imaging modalities using ionizing radiation, radiation exposure of the patients is a vital issue. It is important to survey the various dose-reducing techniques to achieve optimal radiation protection while keeping image quality on an optimal level. Method: We reprocessed 105 patients’ data prospectively between February and April 2017. The determination of the radiation dose was based on the effective dose, calculated by multiplying the dose-length product (DLP) and dose-conversation coefficient. In case of image quality we used signal-to-noise ratio (SNR) based on manual segmentation of region of interest (ROI). For statistical analysis, one sample t-test and Wilcoxon signed rank test were used. Results: Using iterative reconstruction, the effective dose was significantly lower (p<0.001) in both native and contrast-enhanced abdominal, contrast-enhanced chest CT scans and in the case of the total effective dose. At native and contrast-enhanced abdominal CT scans, the noise content of the images showed significantly lower (p<0.001) values for iterative reconstruction images. At contrast-enhanced chest CT scans there was no significant difference between the noise content of the images (p>0.05). Conclusion: Using iterative reconstruction, it was possible to achieve significant dose reduction. Since the noise content of the images was not significantly higher using the iterative reconstruction compared to the filtered back projection, further dose reduction can be achievable while preserving the optimal quality of the images. Orv Hetil. 2019; 160(35): 1387–1394.

Abstract: Introduction: Image-guided intensity-modulated radiation therapy is essential for oncology treatment of head-and-neck cancer patients. Aim: MV-kV and CBCT modalities were compared in case of IGRT treatment for head-and-neck cancer patients. Setup error, setup margin (SM), imaging and evaluation times and imaging doses were analyzed. Method: Eight patients’ elective treatment was evaluated, 66 orthogonal MV-kV images and 66 CBCT series were acquired. Setup error measurement was based on bony manual image registration in three translational directions. Normality test and F-test were performed followed by the comparison with independent-samples T-test (p<0,05). The necessary target volume setup margin was calculated based on Van Herk’s equation. Imaging time and setup error determination time were measured. Imaging doses were estimated based on the literature. Results: No statistically significant difference was found between setup errors determined by MV-kV and CBCT (VRT: 0.5 mm, SD = 1.9 vs. 0.4 mm, SD = 2.1, p = 0.371; LNG: 0.2 mm, SD = 2.2 vs. –0.1 mm, SD = 2.2, p = 0.188; LAT: 0.2 mm, SD = 2.2 vs. 0.3 mm, SD = 2.1, p = 0.41). SM values were: VRT: 2.7 mm vs. 2.5 mm; LNG: 2.1 mm vs. 1.3 mm; LAT: 2.2 mm vs. 2.3 mm. Mean imaging time was 0.65 min (MV-kV) vs. 2.29 min (CBCT). Mean setup error determination time was 2.41 min for both modalities. Estimated imaging doses were 6.88 mGy (MV-kV) vs. 17.2 mGy (CBCT) per fraction. Conclusion: The bony anatomy derived image registration based translational setup error determination results in similar values either by MV-kV or by CBCT. Using 3 mm setup margin in all the directions might be adequate. Imaging time is less by MV-kV, significant difference in imaging doses did not appear. Using CBCT is generally suggested. MV-kV might be an alternative in case of need for shortened imaging time. Orv Hetil. 2018; 159(29): 1193–1200.

Hollow silica microspheres with promising physical properties (MAT540TM) as support for enzyme immobilization and biocatalyst were investigated in this study. The amine-functionalized MAT540TM was activated by six bisepoxides inclosing different spacers and used as epoxy-functionalized carrier for immobilization of lipase B from Candida antarctica (CaLB). The novel, covalently fixed CaLB biocatalysts were compared in kinetic resolution (KR) of racemic 1-phenyethanol rac-1 and five racemic amines rac-3a-e using shaken flasks and continuous-flow packed-bed microreactors. Mechanic stability, re-usability and the effect of temperature (0–90 °C) on productivity and enantiomer selectivity of the covalently immobilized CaLB were investigated. The best performing CaLB biocatalyst showed good mechanic stability after 24 h operation time in continuous-flow mode at 60 °C and provided in KRs of racemic 1-phenyethanol rac-1 with vinyl acetate and of five racemic amines with isopropyl 2-ethoxyacetate as acylating agent the non-reacted (S)-alcohol [(S)-1] or (S)-amines [(S)-3a-e] and the forming (R)-ester [(R)-2] or (R)-amide [(R)-4a-e] in good yields with high enantiomeric excess (ee > 99 %, for all).

INTRODUCTION:Image-guided intensity-modulated radiation therapy is essential for oncology treatment of head-and-neck cancer patients.AIM:MV-kV and CBCT modalities were compared in case of IGRT treatment for head-and-neck cancer patients. Setup error, setup margin (SM), imaging and evaluation times and imaging doses were analyzed.METHOD:Eight patients' elective treatment was evaluated, 66 orthogonal MV-kV images and 66 CBCT series were acquired. Setup error measurement was based on bony manual image registration in three translational directions. Normality test and F-test were performed followed by the comparison with independent-samples T-test (p<0,05). The necessary target volume setup margin was calculated based on Van Herk's equation. Imaging time and setup error determination time were measured. Imaging doses were estimated based on the literature.RESULTS:No statistically significant difference was found between setup errors determined by MV-kV and CBCT (VRT: 0.5 mm, SD = 1.9 vs. 0.4 mm, SD = 2.1, p = 0.371; LNG: 0.2 mm, SD = 2.2 vs. -0.1 mm, SD = 2.2, p = 0.188; LAT: 0.2 mm, SD = 2.2 vs. 0.3 mm, SD = 2.1, p = 0.41). SM values were: VRT: 2.7 mm vs. 2.5 mm; LNG: 2.1 mm vs. 1.3 mm; LAT: 2.2 mm vs. 2.3 mm. Mean imaging time was 0.65 min (MV-kV) vs. 2.29 min (CBCT). Mean setup error determination time was 2.41 min for both modalities. Estimated imaging doses were 6.88 mGy (MV-kV) vs. 17.2 mGy (CBCT) per fraction.CONCLUSION:The bony anatomy derived image registration based translational setup error determination results in similar values either by MV-kV or by CBCT. Using 3 mm setup margin in all the directions might be adequate. Imaging time is less by MV-kV, significant difference in imaging doses did not appear. Using CBCT is generally suggested. MV-kV might be an alternative in case of need for shortened imaging time. Orv Hetil. 2018; 159(29): 1193-1200.

This work presents a complex metallographic examination of bronze, silver and golden artefacts from early medieval German (Gepid) cemeteries of the Hungarian Plain, focusing on the finds from Tiszapüspöki.A newly developed non-destructive X-ray diffraction method was applied on the artefacts for the first time, as a novel approach, for sampling-free residual stress measurements. Other techniques such as optical microscopy and scanning electron microscopy combined with energy dispersive spectrometry has also been used. In addition to residual stress, crystallographic texture and properties of the reflections were analysed as well. The combined application of these methods was found to be an effective tool to deduce the production technologies of the examined artefacts. In addition to defining the characteristics of the material structures and compositions on the surfaces of the artefacts, the typical traces of several technological methods as casting, forming, coating were detected which are used for making various types of artefacts.

The aim of the present study was to examine the prognostic significance of heart rate and its trend in heart transplantation.This observational study enrolled 170 patients who received a bicaval heart transplant between 1995 and 2005; all were in sinus rhythm. The resting heart rate was determined via electrocardiography at the end of the first posttransplant year and annually until the tenth year. Cox analysis was used to evaluate the incidence of adverse events with a mean (standard deviation) follow-up of 8.9 (3.1) years. The primary study end point was the composite outcome of death or graft dysfunction.The resting heart rate at the end of the first posttransplant year was an independent predictor of the primary composite end point (hazard ratio = 1.054; 95% confidence interval, 1.028-1.080; P < .001) and was significantly associated with total mortality (hazard ratio = 1.058; 95% confidence interval, 1.030-1.087; P < .001) and mortality from cardiac causes (hazard ratio = 1.069; 95% confidence interval, 1.026-1.113; P = .001), but not with graft dysfunction (hazard ratio = 1.028; 95% confidence interval, 0.989-1.069; P = .161). For patients with a heart rate ≥ 105 or < 90 bpm vs those with 90-104 bpm, the hazard ratios of the primary end point were 2.233 (95% confidence interval, 1.250-3.989; P = .007) and 0.380 (95% confidence interval, 0.161-0.895; P = .027), respectively. Heart rate tended to decrease in the first 10 years after transplantation (P = .001). Patients with a net increase in heart rate during follow-up showed a higher incidence of adverse events.An elevated heart rate is an adverse prognostic marker after heart transplantation.Estudiar la evolución y el significado pronóstico de la frecuencia cardiaca tras el trasplante cardiaco.Estudio observacional de 170 pacientes que recibieron un trasplante cardiaco bicavo entre 1995 y 2005; todos estaban en ritmo sinusal. La frecuencia cardiaca en reposo se determinó a partir de electrocardiogramas al final del primer año tras el trasplante y anualmente hasta el décimo año. Mediante análisis de Cox, se evaluó la incidencia de eventos adversos en un seguimiento medio de 8,9 ± 3,1 años. El evento principal del estudio fue la variable combinada muerte o disfunción del injerto.La frecuencia cardiaca en reposo, medida al final del primer año tras el trasplante, fue un predictor independiente del evento combinado principal (hazard ratio = 1,054; intervalo de confianza del 95%, 1,028-1,080; p < 0,001). Se observó una asociación estadísticamente significativa con la mortalidad total (hazard ratio = 1,058; intervalo de confianza del 95%, 1,030-1,087; p < 0,001) y con la mortalidad por causas cardiacas (hazard ratio = 1,069; intervalo de confianza del 95%, 1,026-1,113; p = 0,001), pero no con la disfunción del injerto (hazard ratio = 1,028; intervalo de confianza del 95%, 0,989-1,069; p = 0,161). Para los pacientes con frecuencia cardiaca ≥ 105 y < 90 lpm frente a aquellos con 90-104 lpm, las hazard ratio del evento principal fueron, respectivamente, 2,233 (intervalo de confianza del 95%, 1,250-3,989, p = 0,007) y 0,380 (intervalo de confianza del 95%, 0,161-0,895; p = 0,027). Este parámetro presentó una tendencia decreciente en los primeros 10 años del trasplante (p = 0,001). Los pacientes con incremento neto de frecuencia cardiaca en el seguimiento mostraron mayor incidencia de eventos adversos.La frecuencia cardiaca elevada es un marcador pronóstico adverso tras el trasplante cardiaco.

With the development of radiation therapy technology, the utilization of more accurate patient fixation, inclusion of PET/CT image fusion into treatment planning, 3D image-guided radiotherapy, and intensity-modulated dynamic arc irradiation, the application of hypofractionated stereotactic radiotherapy can be extended to specified extracranial target volumes, and so even to the treatment of various metastases. Between October 2012 and August 2014 in our institute we performed extracranial, hypofractionated, image-többguided radiotherapy with RapidArc system for six cases, and 3D conformal multifield technique for one patient with Novalis TX system in case of different few-numbered and slow-growing metastases. For the precise definition of the target volumes we employed PET/CT during the treatment planning procedure. Octreotid scan was applied in one carcinoid tumour patient. Considering the localisation of the metastases and the predictable motion of the organs, we applied 5 to 20 mm safety margin during the contouring procedure. The average treatment volume was 312 cm3. With 2.5-3 Gy fraction doses we delivered 39-45 Gy total dose, and the treatment duration was 2.5 to 3 weeks. The image guidance was carried out via ExacTrac, and kV-Cone Beam CT equipment based on an online protocol, therefore localisation differences were corrected before every single treatment. The patients tolerated the treatments well without major (Gr>2) side effects. Total or near total regression of the metastases was observed at subsequent control examinations in all cases (the median follow-up time was 5 months). According to our first experience, extracranial, imageguided hypofractionated radiotherapy is well-tolerated by patients and can be effectively applied in the treatment of slow-growing and few-numbered metastases.

BACKGROUND AND PURPOSE:Treatment of central nervous system (CNS) tumors has always played an important role in development of radiotherapy techniques. Precise patient immobilisation, non-coplanar field arrangement, conformal treatment, arc therapy, radiosurgery, application of image fusion to radiation planning or re-irradiation were first introduced into clinical routine in the treatment of brain tumors.METHODS:A modern multifunctional radiation instrument, Novalis TX has been installed at the University of Pécs two years ago. New methods, such as real time 3D image guided therapy, dynamic arc therapy and ultra-conformity offer further progress in treatment of CNS tumors. Whole brain irradiation and simultaneous fractionated stereotactic radiosurgery or integrated boost seem to be an optimal method in the treatment of not only soliter or oligo, but even a higher number (4-9) and not typically radiosensitive brain metastases. The new treatment strategy is illustrated by presentation of four case histories.RESULTS:Treatment protocol was completed in all cases. Treatment period of 1.5 to 3 weeks, and treatment time of only a few minutes were not stressful for the patients. A quite remarkable clinical improvement as to general condition of the patients was experienced in three cases. Follow-up images confirmed either remission or a stable disease.CONCLUSIONS:Simultaneous whole brain radiotherapy and integrated stereotactic radiosurgery is a reproducible, safe method that offers an effective irradiation with delivery of definitive dosage even in cases with radio-insensitive brain metastasis.

Since immobilization of lipases enhances their productivity, stability and selectivity, a series of surface modified silica gel supports was developed and used for hydrophobic adsorption of Lipase AK from Pseudomonas fluorescens and Lipase PS from Burkholderia cepacia.