| 1. |
|
|
| 2. |
|
|
| 3. |
- Röme, Andrada, et al.
(författare)
-
Critical Role of P-Selectin and Lymphocyte Function Antigen-1 in Radiation-Induced Leukocyte-Endothelial Cell Interactions in the Colon.
- 2007
-
Ingår i: Diseases of the Colon & Rectum. - : Ovid Technologies (Wolters Kluwer Health). - 0012-3706. ; 50:12, s. 2194-2202
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose Radiation therapy is frequently used in treating different types of tumors, although associated with serious side effects, such as fibrosis and complicated diarrhea. This study was designed to define the adhesive mechanisms behind radiotherapy-induced leukocyte recruitment in the colon. Methods All mice, except control animals, were radiated with a single dose of 20 Gy. Mice were pretreated with an isotype-matched control antibody or a monoclonal antibody directed against P-selectin. In separate experiments, lymphocyte function antigen-1–deficient animals were used. Leukocyte rolling and firm adhesion were determined by use of inverted intravital fluorescence microscopy 16 hours after radiation. Results It was found that immunoneutralization of P-selectin reduced leukocyte rolling by 83 percent and adhesion by 87 percent in radiated mice. Moreover, radiation-induced leukocyte adhesion in LFA-1-deficient mice was decreased by 94 percent compared with wild-type animals. Conclusions This study demonstrates that leukocyte rolling is mediated by P-selectin and that firm leukocyte adhesion is supported by lymphocyte function antigen-1 in radiation-induced enteritis. Moreover, P-selectin-dependent leukocyte rolling is a precondition for subsequent leukocyte adhesion in radiation-induced intestinal injury. Thus, targeting P-selectin and/or lymphocyte function antigen-1 may protect against pathologic inflammation in the colon induced by radiotherapy.
|
|
| 4. |
- Sandborg, Michael, 1961-, et al.
(författare)
-
Demonstration of correlations between clinical and physical image quality measures in chest and lumbar spine screen-film radiography
- 2001
-
Ingår i: British Journal of Radiology. - : British Institute of Radiology. - 0007-1285 .- 1748-880X. ; 74:882, s. 520-528
-
Tidskriftsartikel (refereegranskat)abstract
- The ability to predict clinical image quality from physical measures is useful for optimization in diagnostic radiology. In this work, clinical and physical assessments of image quality are compared and correlations between the two are derived. Clinical assessment has been made by a group of expert radiologists who evaluated fulfilment of the European image criteria for chest and lumbar spine radiography using two scoring methods: image criteria score (ICS) and visual grading analysis score (VGAS). Physical image quality measures were calculated using a Monte Carlo simulation model of the complete imaging system. This model includes a voxelized male anatomy and was used to calculate contrast and signal-to-noise ratio of various important anatomical details and measures of dynamic range. Correlations between the physical image quality measures on the one hand and the ICS and VGAS on the other were sought. 16 chest and 4 lumbar spine imaging system configurations were compared in frontal projection. A statistically significant correlation with clinical image quality was found in chest posteroanterior radiography for the contrast of blood vessels in the retrocardiac area and a measure of useful dynamic range. In lumbar spine anteroposterior radiography, a similar significant correlation with clinical image quality was found between the contrast and signal-to-noise ratio of the trabecular structures in the L1-L5 vertebrae. The significant correlation shows that clinical image quality can, at least in some cases, be predicted from appropriate measures of physical image quality.
|
|
| 5. |
|
|
| 6. |
- Andersson, Martin, et al.
(författare)
-
Improved age and gender specific radiation risk models applied on cohorts of Swedish patients
- 2021
-
Ingår i: Radiation Protection Dosimetry. - : Oxford University Press (OUP). - 0144-8420 .- 1742-3406. ; 195:3-4, s. 334-338
-
Tidskriftsartikel (refereegranskat)abstract
- AIM:The aim of this study is to implement lifetime attributable risk (LAR) predictions for radiation induced cancers for Swedish cohorts of patients of various age and sex, undergoing diagnostic investigations by nuclear medicine methods. METHODS: Calculations are performed on Swedish groups of patients with Paget's disease and with bone metastases from prostatic cancer and diagnosed with bone scintigraphy with an administration of 500 MBq 99mTc-phosphonate. RESULTS: The inclusion of patient survival rates into the calculations lowers the induced radiation cancer risk, as it takes into account that cohorts of patients have shorter predicted survival times than the general population. CONCLUSION: LAR estimations could be valuable for referring physicians, nuclear medicine physicians, nurses, medical physicists, radiologists, and oncologists and as well as ethical committees for risk estimates for specific subgroups of patients. Caution is however advised with respect to application of LAR predictions to individuals (because of individual sensitivities, circumstances, etc.).
|
|
| 7. |
- Andersson, Martin, et al.
(författare)
-
Improved Patient Dosimetry at Radioiodine Therapy by Combining the ICRP Compartment Model and the EANM Pre-Therapeutic Standard Procedure for Benign Thyroid Diseases
- 2021
-
Ingår i: Frontiers in Endocrinology. - : Frontiers Media SA. - 1664-2392. ; 12
-
Tidskriftsartikel (refereegranskat)abstract
- Radioactive iodine is commonly used for the treatment of different thyroid conditions since the 1940s. The EANM has developed a standard pre-therapeutic procedure to estimate patient specific thyroid uptake at treatment of benign thyroid diseases. The procedure which models the time dependent fractional thyroid uptake is based on a two-compartment fitting system, one representing the thyroid and the other the blood. The absorbed dose is however only estimated for the thyroid and not for any other organ in the body. A more detailed biokinetic model for iodine is given by the ICRP and includes an iodide transport in the whole body. The ICRP model has 30 different compartments and 48 transfer coefficients to model the biokinetics of iodide and to model different transfer for inorganic iodide and organic iodine. The ICRP model is a recirculation iodine model, and the optimization is performed on the whole model and not exclusively on the thyroid as in the EANM procedure. Combining the EANM method and the ICRP model gives both patient specific estimations of thyroid uptake and retention and include most organs in the body. The new software gives both an improved patient specific dosimetry for the thyroid and an estimation of the absorbed dose to non-target organs and tissues like kidneys, urinary bladder, stomach wall, and uterus. Using the method described in this paper, the repercussions on the daily routines will be minimal.
|
|
| 8. |
- Andersson, Martin, et al.
(författare)
-
Lifetime attributable risk as an alternative to effective dose to describe the risk of cancer for patients in diagnostic and therapeutic nuclear medicine
- 2017
-
Ingår i: Physics in Medicine and Biology. - : IOP Publishing. - 0031-9155 .- 1361-6560. ; 62:24, s. 9177-9188
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of this study is to implement lifetime attributable risk (LAR) predictions of cancer for patients of various age and gender, undergoing diagnostic investigations or treatments in nuclear medicine and to compare the outcome with a population risk estimate using effective dose and the International Commission on Radiological Protection risk coefficients. The radiation induced risk of cancer occurrence (incidence) or death from four nuclear medicine procedures are estimated for both male and female between 0 and 120 years. Estimations of cancer risk are performed using recommended administered activities for two diagnostic (18F-FDG and 99mTc-phosphonate complex) and two therapeutic (131I-iodide and 223Ra-dichloride) radiopharmaceuticals to illustrate the use of cancer risk estimations in nuclear medicine. For 18F-FDG, the cancer incidence for a male of 5, 25, 50 and 75 years at exposure is 0.0021, 0.0010, 0.0008 and 0.0003, respectively. For 99mTc phosphonates complex the corresponding values are 0.000 59, 0.000 34, 0.000 27 and 0.000 13, respectively. For an 131I-iodide treatment with 3.7 GBq and 1% uptake 24 h after administration, the cancer incidence for a male of 25, 50 and 75 years at exposure is 0.041, 0.029 and 0.012, respectively. For 223Ra-dichloride with an administration of 21.9 MBq the cancer incidence for a male of 25, 50 and 75 years is 0.31, 0.21 and 0.09, respectively. The LAR estimations are more suitable in health care situations involving individual patients or specific groups of patients than the health detriment based on effective dose, which represents a population average. The detriment consideration in effective dose adjusts the cancer incidence for suffering of non-lethal cancers while LAR predicts morbidity (incidence) or mortality (cancer). The advantages of these LARs are that they are gender and age specific, allowing risk estimations for specific patients or subgroups thus better representing individuals in health care than effective dose.
|
|
| 9. |
- Börjesson, J., et al.
(författare)
-
X-ray fluorescence analysis in medical sciences: A review
- 2003
-
Ingår i: Acta Diabetologica. - : Springer Science and Business Media LLC. - 0940-5429 .- 1432-5233. ; 40
-
Tidskriftsartikel (refereegranskat)abstract
- Some elements have toxic effects on the human body and there is thus a need to control their levels in human organs and tissues. Moreover, it is important to increase our knowledge of relationships between observable toxic effects and element concentrations in man and his environment. Monitoring and basic occupational and environmental research rely on measurements directly in humans as well as samples from humans and the environment. This paper reviews recent advances in in vivo X-ray fluorescence methods and their applications.
|
|
| 10. |
- Giussani, Augusto, et al.
(författare)
-
A Compartmental Model for Biokinetics and Dosimetry of 18F-Choline in Prostate Cancer Patients
- 2012
-
Ingår i: Journal of Nuclear Medicine. - : Society of Nuclear Medicine. - 0161-5505 .- 2159-662X. ; 53:6, s. 985-993
-
Tidskriftsartikel (refereegranskat)abstract
- PET with F-18-choline (F-18-FCH) is used in the diagnosis of prostate cancer and its recurrences. In this work, biodistribution data from a recent study conducted at Skane University Hospital Malmo were used for the development of a biokinetic and dosimetric model. Methods: The biodistribution of F-18-FCH was followed for 10 patients using PET up to 4 h after administration. Activity concentrations in blood and urine samples were also determined. A compartmental model structure was developed, and values of the model parameters were obtained for each single patient and for a reference patient using a population kinetic approach. Radiation doses to the organs were determined using computational (voxel) phantoms for the determination of the S factors. Results: The model structure consists of a central exchange compartment (blood), 2 compartments each for the liver and kidneys, 1 for spleen, 1 for urinary bladder, and 1 generic compartment accounting for the remaining material. The model can successfully describe the individual patients' data. The parameters showing the greatest interindividual variations are the blood volume (the clearance process is rapid, and early blood data are not available for several patients) and the transfer out from liver (the physical half-life of F-18 is too short to follow this long-term process with the necessary accuracy). The organs receiving the highest doses are the kidneys (reference patient, 0.079 mGy/MBq; individual values, 0.033-0.105 mGy/MBq) and the liver (reference patient, 0.062 mGy/MBq; individual values, 0.036-0.082 mGy/MBq). The dose to the urinary bladder wall of the reference patient varies between 0.017 and 0.030 mGy/MBq, depending on the assumptions on bladder voiding. Conclusion: The model gives a satisfactory description of the biodistribution of F-18-FCH and realistic estimates of the radiation dose received by the patients.
|
|
