| 51. |
- Ljungberg, Maria, et al.
(författare)
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31P MR spectroscopy to evaluate the efficacy of hepatic artery embolization in the treatment of neuroendocrine liver metastases.
- 2012
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Ingår i: Acta radiologica (Stockholm, Sweden : 1987). - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 53:10, s. 1118-1126
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundIt is common to treat patients with metastatic disease from gastrointestinal neuroendocrine (NE) tumors with surgical reduction to prolong survival. This can be combined with hepatic arterial embolization (HAE) and medical treatment to reduce hormonal symptoms. Today there are no rapid and reliable methods to evaluate the efficacy of HAE in the treatment of neuroendocrine liver metastasis.PurposeTo investigate metabolic changes in hepatic metastases of NE tumors following HAE, and to establish if there are any early spectral patterns that might indicate therapeutic efficacy based on in vivo (31)P MRS data.Material and MethodsVolume selective (31)P MRS was used to study 11 patients with disseminated NE tumors with regional lymph nodes and bilobar liver metastases. Measurements were performed before and 1 and 3 days after HAE.ResultsNon-responders had significantly higher PME/Pi and αNTP/ΣNTP ratios than the responders before HAE (P < 0.05). Three days after HAE, non-responders still had significantly higher αNTP/ΣNTP than the responders did (P < 0.05). We also observed trends for increased PME ratios 3 days after HAE, decreased ATP-levels, and liberated Pi in responders.ConclusionThis (31)P-MRS study showed significant differences in PME/Pi and αNTP/ΣP ratios between responders and non-responders on the day before HAE, which is an interesting finding that may reflect intrinsic properties of the tumor tissue. We also observed trends for cell membrane renewal and increased energy consumption in responders after HAE. These results demonstrate potentials for (31)P-MRS to predict individual responsiveness prior to HAE.
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| 52. |
- Nakajima, K., et al.
(författare)
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Improved quantification of small hearts for gated myocardial perfusion imaging
- 2013
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Ingår i: European Journal of Nuclear Medicine and Molecular Imaging. - : Springer Science and Business Media LLC. - 1619-7070 .- 1619-7089. ; 40:8, s. 1163-1170
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Tidskriftsartikel (refereegranskat)abstract
- In patients with a small heart, defined as an end-systolic volume (ESV) of a parts per thousand currency sign20 mL calculated using the Quantitative Gated SPECT (QGS) program, underestimation of ESV and overestimation of ejection fraction (EF) using gated myocardial perfusion imaging are considered errors caused by inappropriate delineation of the left ventricle (LV). The aim of this study was to develop a new method for delineation of the LV and to evaluate it in studies using a digital phantom, normal subjects and patients. The active shape-based method for LV delineation, EXINI heart (ExH), was adjusted to more accurately process small hearts. In small hearts, due to the partial volume effect and the short distance to the opposite ventricular wall, the endocardial and the epicardial surfaces are shifted in the epicardial direction depending on the midventricular volume. The adjusted method was evaluated using digital XCAT phantoms with Monte Carlo simulation (8 virtual patients), a Japanese multicentre normal database (69 patients) and consecutive Japanese patients (116 patients). The LV volumes, EF and diastolic parameters derived from ExH and QGS were compared. The digital phantom studies showed a mean ESV of 87 % +/- 9 % of the true volume calculated using ExH and 22 % +/- 18 % calculated using QGS. In the normal database, QGS gave higher EFs in women than in men (71.4 +/- 6.0 % vs. 67.2 +/- 6.0 %, p = 0.0058), but ExH gave comparable EFs (70.7 +/- 4.9 % and 71.4 +/- 5 % in men and women, respectively, p = ns). QGS gave higher EFs in subjects with a small heart than in those with a normal-sized heart (74.5 +/- 5.1 % vs. 66.1 +/- 4.9 %), but ExH gave comparable values (70.0 +/- 5.9 % vs. 71.6 +/- 4.2 %, respectively, p = ns). In consecutive patients, the average EFs with QGS in patients with ESV > 20 mL, 11-20 mL and a parts per thousand currency sign10 mL were 57.9 %, 71.9 % and 83.2 %, but with ExH the differences among these groups were smaller (65.2 %, 67.8 % and 71.5 %, respectively). The volume-dependent edge correction algorithm was able to effectively reduce the effects on ESV and EF of a small heart. The uniform normal values might be applicable to both men and women and to both small and normal-sized hearts.
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| 53. |
- Sandblom, Viktor, 1987, et al.
(författare)
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Radiolabelled pharmaceuticals MIBG and octreotate for treatment of metastatic pheochromocytoma and paraganglioma
- 2014
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Ingår i: SweRays Workshop, Malmö, Sweden, Aug 20-22, 2014.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Background: The 5-year survival for patients with metastatic pheochromocytoma (PC) and paraganglioma (PGL) is less than 50%. There is a clear need for development of better diagnostic and therapeutic options for these patients. Radionuclide therapy offers the possibility to treat spread PC/PGL. The norepinephrine (NE) analogue metaiodobenzylguanidine (MIBG) and the somatostatin (SST) analogues octreotate or octreotide are possible molecules that could be used for this purpose. These analogues have different biodistribution and different organs at risk, when used for therapy. Thus, combined therapy, using both radiolabelled NE and SST analogues, might be beneficial for these patients. Aim: The aim of this study was to evaluate the possibility of using 177Lu-octreotate and/or 131I-MIBG for treatment of patients with metastatic PC/PGL. Materials and Methods: Three patients with metastatic PC/PGL were injected with 131I-MIBG and 111In-octreotide, and four patients with metastatic PC/PGL were injected with 111In-octreotide, before surgical removal of the primary tumour. During surgery, tissue samples of tumour, blood, fat and muscle were collected and weighed, and the radioactivity was measured in a gamma counter. The activity concentration in these tissue samples was then calculated for each radionuclide. Additionally, tumour-to-blood activity concentration ratios (T/B) were calculated. Results: The activity concentrations and T/B values showed large variations between patients. For 111In-octreotide, T/B values were 25-590 and for 131I-MIBG, the corresponding values were 0-1600. Conclusion: The sometimes high T/B values show a clear possibility of using 177Lu-octreotate and 131I-MIBG for treatment of some patients with metastatic PC/PGL. However, due to the large variation between patients, individual investigation of tumour uptake prior to treatment is required.
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| 54. |
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| 55. |
- Spetz, Johan, et al.
(författare)
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Specific binding and uptake of 131I-MIBG and 111In-octreotide in malignant paraganglioma - tools for choice of radionuclide therapy
- 2012
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Ingår i: Hormone and Metabolic Research. - : Georg Thieme Verlag KG. - 0018-5043 .- 1439-4286. ; 44:5, s. 400-404
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Tidskriftsartikel (refereegranskat)abstract
- Tumor-specific uptake of the radiolabeled nor-epinephrine analogue meta-iodobenzylguanidine via norepinephrine transporter or radiolabeled somatostatin analogues octreotide/octreotate via somatostatin receptors offers possibilities to diagnose and treat metastatic pheochromocytoma/paraganglioma. High uptake of 123I-meta-iodobenzylguanidine is dependent on high expression of vesicular monoamine transporters responsible for mediating uptake of biogenic amines into dense core granules. A patient with metastatic paraganglioma (liver and bone metastases) underwent surgical removal of the primary after injection of 131I-meta-iodobenzylguanidine and 111In-octreotide. Radioactivity was determined in biopsies from tumor and normal tissue biopsies. The tumor/blood concentration value was high: 180 for 131I-meta-iodobenzylguanidine 3 h after injection and 590 for 111In-octreotide 27 h after injection. Studies of primary tumor cell cultures demonstrated increased cell membrane binding and internalization over time for 131I-meta-iodobenzylguanidine. The vesicular monoamine transporter antagonist reserpine and the norepinephrine transporter inhibitor clomipramine reduced internalization by 90% and 70%, respectively, after 46 h of incubation. The results demonstrated increased cell membrane binding and internalization over time also for 111In-octreotide. Internalization was highest for a low concentration of 111In-octreotide. Excess of octreotide reduced internalization of 111In-octreotide with 75% after 46 h of incubation. In conclusion, uptake and tumor/blood concentration values of radiolabeled meta-iodobenzylguanidine and somatostatin analogues can be determined for metastatic pheochromocytoma/paraganglioma to evaluate the possibility to use one or both agents for therapy. For this patient, the high tumor/blood values clearly demonstrated that therapy using both radiopharmaceuticals would be most beneficial. In vitro studies verified specific cell-membrane binding and internalization in tumor cells of both radiopharmaceuticals.
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| 56. |
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| 57. |
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| 58. |
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| 59. |
- Tornberg, Åsa, et al.
(författare)
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Relation between cycling exercise capacity, fiber-type composition, and lower extremity muscle strength and muscle endurance.
- 2011
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Ingår i: Journal of Strength and Conditioning Research. - 1533-4287. ; 25:1, s. 16-22
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Tidskriftsartikel (refereegranskat)abstract
- Segerström, ÅB, Holmbäck, AM, Hansson, O, Elgzyri, T, Eriksson, K-F, Ringsberg, K, Groop, L, Wollmer, P, and Thorsson, O. Relation between cycling exercise capacity, fiber-type composition, and lower extremity muscle strength and muscle endurance. J Strength Cond Res 25(1): 16-22, 2011-The aim of the study was to determine the relation between peak oxygen uptake (&OV0312;o2peak), peak work rate (WRpeak), fiber-type composition, and lower extremity strength and endurance during a maximal incremental cycle test. Thirty-nine healthy sedentary men, aged 30-46, participated in the study. Subjects performed a maximal incremental cycle test and isokinetic knee extension (KE) and flexion (KF) strength and endurance tests at velocities of 60 and 180°·s. Muscle biopsies were taken from m. vastus lateralis and analyzed for fiber-type composition. A significant correlation existed between KE strength and &OV0312;o2peak and WRpeak. Also, KF endurance correlated significantly to &OV0312;o2peak and WRpeak. The KE endurance correlated significantly to WRpeak (rp = 0.32, p < 0.05) and almost significantly to &OV0312;o2peak (rp = 0.28, p = 0.06). Stepwise multiple regression analyses showed that KE strength, KF endurance, and the percentage of type I fibers could explain up to 40% of the variation in &OV0312;o2peak and WRpeak. The performance of sedentary subjects in a maximal incremental cycle test is highly affected by knee muscle strength and endurance. Fiber-type composition also contributes but to a smaller extent.
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| 60. |
- Tornberg, Åsa, et al.
(författare)
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Upper Body Muscle Strength and Endurance in Relation to Peak Exercise Capacity During Cycling in Healthy Sedentary Male Subjects.
- 2011
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Ingår i: Journal of Strength and Conditioning Research. - 1533-4287. ; 25, s. 1413-1417
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Tidskriftsartikel (refereegranskat)abstract
- Segerström, AB, Holmbäck, AM, Elzyri, T, Eriksson, KF, Ringsberg, K, Groop, L, Thorsson, O, and Wollmer, P. Upper body muscle strength and endurance in relation to peak exercise capacity during cycling in healthy sedentary male subjects. J Strength Cond Res 24(x): 000-000, 2010-The aim of this study was to investigate the relation between upper body muscle strength and endurance, and exercise capacity during an incremental cycle exercise test in sedentary healthy male subjects before and after 6 months of combined supervised group training. Exercise capacity was measured as maximal oxygen consumption (&OV0312;O2peak) and maximum work rate (WRpeak). Muscle strength and endurance of the upper body were assessed by bench press and isometric measurement of trunk extensor and flexor maximum voluntary contraction (MVC) and trunk extensor and flexor endurance. Thirty-one subjects were studied before and after the training period. Bench press and trunk extensor MVC correlated to exercise capacity at baseline and after training. Training improved &OV0312;O2peak and WRpeak. The correlation between trunk extensor MVC and exercise capacity improved after training. Upper body strength may affect exercise capacity by increasing the rider's ability to generate force on the handlebar that can be transmitted to the pedals. Resistance training of the arms, chest, and trunk may help improve cycling performance.
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