| 1. |
- Andersson, Lars-Göran, et al.
(författare)
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Thallium-201 Myocardial Imaging at Rest in Male Orienteers and Other Endurance Athletes
- 2001
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Ingår i: Upsala Journal of Medical Sciences. - : Uppsala Medical Society. - 0300-9734 .- 2000-1967. ; 106:1, s. 59-66
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Tidskriftsartikel (refereegranskat)abstract
- During the period 1979 to 1992, 16 sudden unexpected cardiac deaths were known to have occurred in young Swedish orienteers. Autopsy indicated myocarditis to be the most frequent finding, most often combined with extensive myocardial fibrosis. The aim of the present investigation was to explore whether young male orienteers show a higher frequency than other young elite endurance athletes (controls) in the occurrence of Thallium-201 myocardial perfusion defects at rest, suggestive of fibrosis evoked by myocarditis. Thallium-201 perfusion abnormalities at rest were more frequently found in the controls than in the orienteers (26% vs. 12%, p=0.03). Uneven Tl-201 perfusion was associated with left ventricular mass (r=0.32, r=0.24, p<0.01, p=0.02) and body weight (r=0.30, r=0.31, p<0.01, p=0.03) in orienteers and controls, respectively. Echocardiographic left ventricular wall motion abnormalities were found in 11 athletes (9 orienteers and 2 controls) but only two displayed an abnormal Thallium-201 perfusion scan at rest. Perfusion abnormalities at rest did not occur more frequently in the orienteers but were commonly found in both groups of apparently healthy athletes making it futile to discern abnormals from normals. Thallium-201 perfusion aberrations were not associated with left ventricular wall motion abnormalities obtained by echocardiography.
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| 2. |
- Strang, Christof M., et al.
(författare)
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Improved ventilation-perfusion matching by abdominal insufflation (pneumoperitoneum) with CO2 but not with air
- 2013
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Ingår i: Minerva Anestesiologica. - 0375-9393 .- 1827-1596. ; 79:6, s. 617-625
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Tidskriftsartikel (refereegranskat)abstract
- Background. Pneumoperitoneum (PP) by CO2-insufflation causes atelectasis however with maintained or even improved oxygenation. We studied the effect of abdominal insufflation by carbon dioxide (CO2) and air on gas exchange during PP. Methods. Twenty-seven anesthetized pigs were studied during PP with insufflations to 12 mmHg by either 1/CO2, 2/ air or 3/CO2 during intravenous nitroprusside infusion (SNP) (N.=9 in each group). In 3 pigs in each group, gamma camera technique (SPECT) was used to study ventilation and perfusion distributions, in another 6 pigs an inert-gas technique (MIGET) was used for assessing ventilation-perfusion matching (V-A/Q). Measurements were made during anesthesia before and after 60 minutes of PP. Results. CO2-PP caused a shift of blood flow away from dependent, non-ventilated (atelectatic) to ventilated regions. Air-PP caused smaller, and SNP-PP even less shift of lung blood flow. Shunt decreased luring CO2-PP (6+/-1% compared to baseline 9+/-2%, P<0.05), did not change during Air-PP (10+/-2%) and increased during SNP-PP (16+/-2%, P<0.05). PaO2 increased from baseline 35+/-2 to 41+/-3 kPa during CO2-PP and decreased to 32+/-3 kPa during Air-PP and to 27+/-3 kPa during SNP-PP (P<0.05 for all three comparisons). PaCO2 increased during CO2- and SNP-PP. Conclusion. CO2-PP enhanced the shift of blood flow towards better ventilated areas of the lung compared to Air-PP and SNP blunted the effects seen with CO2-PP. SNP may thus have blunted and CO2 potentiated vasoconstriction, by hypoxic pulmonary vasoconstriction or another mechanism.
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| 3. |
- Strang, Christof M., et al.
(författare)
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Improved ventilation-perfusion matching with increasing abdominal pressure during CO(2)-pneumoperitoneum in pigs
- 2011
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Ingår i: Acta Anaesthesiologica Scandinavica. - : Wiley. - 0001-5172 .- 1399-6576. ; 55:7, s. 887-896
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Tidskriftsartikel (refereegranskat)abstract
- Background: CO(2)-pneumoperitoneum (PP) is performed at varying abdominal pressures. We studied in an animal preparation the effect of increasing abdominal pressures on gas exchange during PP. Methods: Eighteen anaesthetized pigs were studied. Three abdominal pressures (8, 12 and 16mmHg) were randomly selected in each animal. In six pigs, single-photon emission computed tomography (SPECT) was used for the analysis of V / Q distributions; in another six pigs, multiple inert gas elimination technique (MIGET) was used for assessing V / Q matching. In further six pigs, computed tomography (CT) was performed for the analysis of regional aeration. MIGET, CT and central haemodynamics and pulmonary gas exchange were recorded during anaesthesia and after 60min on each of the three abdominal pressures. SPECT was performed three times, corresponding to each PP level. Results: Atelectasis, as assessed by CT, increased during PP and in proportion to abdominal pressure [from 9 +/- 2% (mean +/- standard deviation) at 8mmHg to 15 +/- 2% at 16mmHg, P <0.05]. SPECT during increasing abdominal CO(2) pressures showed a shift of blood flow towards better ventilated areas. V / Q analysis by MIGET showed no change in shunt during 8 mmHg PP (9 +/- 1.9% compared with baseline 9 +/- 1.2%) but a decrease during 12mmHg PP (7 +/- 0.9%, P <0.05) and 16mmHg PP (5 +/- 1%, P <0.01). PaO(2) increased from 39 +/- 10 to 52 +/- 9 kPa (baseline to 16 mmHg PP, P <0.01). Arterial carbon dioxide (PCO(2)) increased during PP and increased further with increasing abdominal pressures. Conclusion: With increasing abdominal pressure during PP perfusion was redistributed more than ventilation away from dorsal, collapsed lung regions. This resulted in a better V / Q match. A possible mechanism is enhanced hypoxic pulmonary vasoconstriction mediated by increasing PCO(2).
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| 4. |
- Sundin, Anders, et al.
(författare)
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Radioimmunolocalization of human colonic cancer xenografts : aspects of extensive purification of monoclonal anti-CEA-antibodies
- 1991
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Ingår i: International journal of radiation applications and instrumentation. Part B, Nuclear medicine and biology. - 0883-2897. ; 18:8, s. 891-899
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Tidskriftsartikel (refereegranskat)abstract
- Tumour-to-normal tissue ratios of i.p. injected 125I-labelled monoclonal antibodies (MAbs), reacting with CEA were determined in nude rats xenografted with human colonic cancer cells (LS 174 T). Two MAbs, I-38S1 and II-16, reactive with the GOLD 1-epitope on CEA were tested. MAb I-38S1 was also tested after additional purification using anion exchange chromatography (thereafter named AEC 38). In the external activity measurements, MAb AEC 38 showed significantly better tumour-to-liver ratios than did MAb II-16 on all 4 days after injection. MAb I-38S1 gave intermediate ratios but was significantly better than II-16 only on day 3. The mean tumour-to-blood ratios were 3.0, 2.6 and 1.5 and the mean tumour-to-liver ratios were 6.6, 4.8 and 3.5 for MAbs AEC 38, I-38S1 and II-16 respectively. Gamma camera registrations in 3 animals on 4 days showed good imaging properties for all three MAbs and the patterns of tissue uptake were consistent with those seen in the external measurements. Furthermore, histopathological and immunohistochemical determinations were performed, showing that MAb II-16 gave about the same spatial binding as the previously analysed MAb I-38S1. The results indicate that additional purification of MAbs using anion exchange chromatography may potentiate tumour uptake in this model.
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