| 1. |
- Lau, Joey, 1979-
(författare)
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Implantation-Site Dependent Differences in Engraftment and Function of Transplanted Pancreatic Islets
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Transplanting pancreatic islets into the liver through the portal vein is currently the most common procedure in clinical islet transplantations for treating patients with brittle type 1 diabetes. However, most islet grafts fail within a 5-year period necessitating retransplantation. The vascular connections are disrupted at islet isolation and implanted islets depend on diffusion of oxygen and nutrients in the immediate posttransplantation period. Rapid and efficient revascularization is of utmost importance for the survival and long-term function of transplanted islets. In this thesis, the influence of the implantation microenvironment for islet engraftment and function was studied. Islets were transplanted into the liver, the renal subcapsular site or the pancreas. Islets implanted into the liver contained fewer glucagon-positive cells than islets implanted to the kidney and endogenous islets. Intraportally transplanted islets responded with insulin and glucagon release to secretagogues, but only when stimulated through the hepatic artery. Thus, the intrahepatic grafts were selectively revascularized from the hepatic artery. The vascular density in human islets transplanted into the liver of athymic mice was markedly lower when compared to human islets grafted to the kidney. Islets implanted into their physiological environment, the pancreas, were markedly better revascularized. Insulin content, glucose-stimulated insulin release, (pro)insulin biosynthesis and glucose oxidation rate were markedly decreased in transplanted islets retrieved from the liver, both when compared to endogenous and transplanted islets retrieved from the pancreas. Only minor changes in metabolic functions were observed in islets implanted into the pancreas when compared to endogenous islets. The present findings demonstrate that the microenvironment has a major impact on the engraftment of transplanted islets. Elucidating the beneficial factors that promote engraftment would improve the survival and long-term function of transplanted islets. Ultimately, islet transplantation may be provided to an increased number of patients with type 1 diabetes.
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| 2. |
- Lau, Joey, et al.
(författare)
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Implantation site-dependent dysfunction of transplanted pancreatic islets
- 2007
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 56:6, s. 1544-1550
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE—Clinical islet transplantations are performed through infusion of islets via the portal vein into the liver. This study aimed at characterizing the influence of the implantation microenvironment on islet graft metabolism and function. RESEARCH DESIGN AND METHODS—Islets were transplanted into their normal environment, i.e., the pancreas, or intraportally into the liver of mice. One month posttransplantation, the transplanted islets were retrieved and investigated for changes in function and gene expression. RESULTS—Insulin content, glucose-stimulated insulin release, (pro)insulin biosynthesis, and glucose oxidation rate were markedly decreased in islets retrieved from the liver, both when compared with islets transplanted into the pancreas and endogenous islets. Islets transplanted into the pancreas showed normal insulin content, (pro)insulin biosynthesis, and glucose oxidation rate but increased basal insulin secretion and impaired glucose stimulation index. Gene expression data for retrieved islets showed downregulation of pancreatic and duodenal homeobox gene-1, GLUT-2, glucokinase, mitochondrial glycerol-phosphate dehydrogenase, and pyruvate carboxylase, preferentially in intraportally transplanted islets. CONCLUSIONS—Islets transplanted into their normal microenvironment, i.e., the pancreas, display gene expression changes when compared with endogenous islets but only moderate changes in metabolic functions. In contrast, site-specific properties of the liver markedly impaired the metabolic functions of intraportally transplanted islets.
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| 3. |
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| 4. |
- Andersson, Ola, et al.
(författare)
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Endogenous Communication and Tacit Coordination in Market Entry Games - An explorative experimental study
- 2006
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- This paper explores experimentally the effects of costly communication possibilities in market entry games. It is shown that these effects depend on whether entry costs are symmetric or asymmetric. In the former, but not the latter case, communication possibilities increase coordination success substantially and are likely to generate inferior outcomes for consumers. Furthermore, cost asymmetries provide a tacit coordination cue that is robust to changes in the game and is used by experienced players as a substitute to communication. It is also shown that although communication opens up for aggressive market domination strategies, such strategies are not used often successful.
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| 5. |
- Bartuma, Katarina, et al.
(författare)
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Knowledge about hereditary nonpolyposis colorectal cancer; mutation carriers and physicians at equal levels
- 2009
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Ingår i: BMC Medical Genetics. - : Springer Science and Business Media LLC. - 1471-2350. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Background: Identification and adequate management of individuals at risk for hereditary nonpolyposis colorectal cancer (HNPCC) is crucial since surveillance programmes reduce morbidity and mortality. We investigated knowledge about key features of HNPCC in at risk individuals and physicians in surgery, gynecology and oncology. Methods: Data were collected using a questionnaire which was answered by 67 mutation carriers and 102 physicians from the southern Swedish health care region. The statements were related to colorectal cancer, heredity and surveillance and the physicians were also asked questions about cancer risks and surveillance strategies. Results: Both groups answered questions on colorectal cancer risk, surveillance and genetic testing well, whereas answers about inheritance and risks for HNPCC associated cancer were less accurate. Only half of the family members and one third of the physicians correctly estimated the risk to inherit an HNPCC predisposing mutation. Among family members, young age (<57 years), female sex and recent genetic counseling significantly correlated with better results. Physicians generally underestimated the risk of HNPCC associated cancers and three out of four suggested a later starting age for surveillance than recommended. Conclusion: The finding of similar levels of knowledge about key features of HNPCC in at risk individuals and physicians reflect the challenge physicians face in keeping up to date on hereditary cancer and may have implications for the clinical management and professional relations with HNPCC family members.
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| 6. |
- Brandhorst, Heide, et al.
(författare)
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New class of oxygen carriers improves islet isolation from long-term stored rat pancreata
- 2008
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Ingår i: Transplantation Proceedings. - : Elsevier BV. - 0041-1345 .- 1873-2623. ; 40:2, s. 393-394
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Pancreas shipment is frequently associated with prolonged ischemia deteriorating islet graft function. The strategy to prevent ischemic damage utilizing perfluorodecalin (PFD) for human pancreas oxygenation does not seem to improve isolation outcome. The present study investigated the efficiency of perfluorohexyloctane (F6H8), a hyperoxygen carrier characterized by low specific density (1.33 g/cm3) and lipophilic qualities, to facilitate islet isolation from long-term stored rat pancreata. MATERIALS AND METHODS: Prior to islet isolation, pancreata were intraductally flushed in situ with Kyoto solution (KS) and stored for 24 hours in KS, oxygenated PFD, or F6H8. RESULTS: Islet isolation performed after 24-hour storage in KS failed completely. The intrapancreatic pO2 in PFD- and F6H8-incubated pancreata was almost the same. In correspondence, the ATP content and viability of isolated islets were similar as well. In contrast, islet yield and in vitro function were significantly reduced after storage in PFD compared with F6H8. CONCLUSION: This study suggested that islet isolation performed after long-term pancreas preservation can be significantly improved utilizing semifluorinated alkanes as oxygen carriers.
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| 7. |
- Brandhorst, Heide, 1962-, et al.
(författare)
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Perfluorohexyloctane improves long-term storage of rat pancreata for subsequent islet isolation
- 2009
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Ingår i: Transplant International. - : Frontiers Media SA. - 0934-0874 .- 1432-2277. ; 22:10, s. 1017-1022
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Tidskriftsartikel (refereegranskat)abstract
- Pancreas oxygenation by means of the hyperoxygen carrier perfluorodecalin (PFD) has been established to prevent ischemically induced damage from cold-stored pancreata. However, large-scale studies did not confirm the promising results that had been observed in smaller donor populations. This study assessed whether islet isolation from pancreata stored for prolonged periods can be improved by utilizing the new oxygen carrier perfluorohexyloctane (F6H8) characterized by lower gravity and higher lipophilicity than PFD. Subsequent to 24 h of storage in either oxygenated PFD or F6H8, the rat pancreata were assessed for the intrapancreatic partial oxygen pressure (pO(2)) and subsequently processed with current standard procedures. The intrapancreatic pO(2) was nearly identical in rat pancreata stored either in PFD or F6H8. Nevertheless, rat islet isolation outcome was significantly increased in terms of yield, integrity, in vitro function and post-transplant outcome after transplantation in diabetic nude mice when F6H8 was used as oxygen carrier. This proof-of-concept study demonstrated in rats that islet isolation performed after long-term storage of oxygenated pancreatic tissue can be significantly improved if PFD was replaced by F6H8.
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| 8. |
- Carlsson, Christina, et al.
(författare)
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Benefits from membership in cancer patient associations: relations to gender and involvement.
- 2006
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Ingår i: Acta oncologica. - : Informa UK Limited. - 0284-186X .- 1651-226X. ; 45:5, s. 559-563
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Tidskriftsartikel (refereegranskat)abstract
- Cancer patient associations report a growing number of members and increasing possibilities to influence health care, but knowledge about the members' views on the benefit of involvement is scarce. We therefore investigated how members (n = 1742) of Swedish patient associations for breast cancer and prostate cancer rate the benefit of membership for their physical and psychological well-being and social adjustment to cancer. Using a scoring scale, 2/3 of the members reported that membership had benefit for psychological well-being, whereas half of the members reported benefit for physical well-being and social adjustment. Individuals who had been actively involved in board work and/or contact person activities within the associations reported significantly more benefit for all three parameters. Gender differences were observed with men, represented by individuals affected by prostate cancer, reporting greater benefit for all three parameters, although especially evident for psychological well-being. Individuals who obtained membership within two years of diagnosis reported greater benefit for psychological well-being and social adjustment compared to those who became members later. In conclusion, members in patient associations for cancer report benefit particularly for their psychological well-being and actively involved members and men affected by prostate cancer perceive the greatest benefit from membership.
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| 9. |
- Carlsson, Per-Ola, et al.
(författare)
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Carbon monoxide and pancreatic islet blood flow in the rat : inhibition of haem oxygenase does not affect islet blood perfusion
- 2006
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Ingår i: Scandinavian Journal of Clinical and Laboratory Investigation. - : Informa UK Limited. - 0036-5513 .- 1502-7686. ; 66:7, s. 543-548
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Tidskriftsartikel (refereegranskat)abstract
- Objective. To determine whether carbon monoxide, a known gaseous vasorelaxator, affects pancreatic islet blood flow in rats. Material and methods. Sprague-Dawley rats were anaesthetized with thiobutabarbital and injected intravenously with the haem oxygenase inhibitor tin-protoporphyrin IX dichloride ( SnPP; 4, 10 or 20 mg/kg body-weight). After 15 min, blood flow measurements were performed using a microsphere technique. Results. There was a slight increase in mean arterial blood pressure with the highest dose of SnPP. No effects on total pancreatic, islet, duodenal, colonic, renal or adrenal blood flow were seen with any of the applied doses. Conclusions. The findings of this study suggest that the haem oxygenase-carbon monoxide system is likely to be of limited importance in the regulation of blood perfusion to the pancreas, the islets of Langerhans or any of the other studied organs.
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| 10. |
- Carlsson, Per-Olof, et al.
(författare)
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Testfasen i miljöklassningsprojekten : Delrapport september 2007
- 2007
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Denna rapport är en redovisning av resultat och underlag i testfasen imiljöklassningsprojekten.I januari 2005 inleddes tre forskningsprojekt med målet att föreslå ettsystem för miljöklassning av byggnader. Forskningsprojekten har engemensam projektgrupp där 27 företag ingår. Syftet med projekten är attta fram förslag till indikatorer och kriterier för klassning inom områdenaenergi, innemiljö och farliga ämnen. Projekten avslutas hösten 2007.Under perioden december 2006 – mars 2007 genomfördes ett test avflera alternativa förslag till indikatorer. Testet utfördes i nära samverkanmed 16 företag från projektgruppen och ytterligare 10 bostadsrättföreningaroch 6 småhusägare. Sammanlagt ingick 46 byggnader av olika typ(flerbostadshus, kontor, sjukhus, småhus etc.).Testet utfördes genom att företag, föreningar och småhusägare samladein nödvändiga data för klassning av ett antal preliminära indikatorer. Defick också svara på frågor om prioritering av aspekter, indikatorer ochvilka resurser som krävdes.Insamlingen av mätdata kompletterades sedan med intervjuer för att fåin ytterligare information och synpunkter.Denna rapport innehåller resultat i form av:Indata från dem som testat.Försök till klassning av respektive byggnad.Synpunkter på genomförandet av testningen.Synpunkter på klassningssystemet.Dessutom ingick en studie av kopplingen mellan energideklarationer ochmiljöklassning. Några av byggnaderna energideklarerades och dessa datajämfördes med vad som behövs för miljöklassning.Rapporten innehåller samtliga dokument från testningen och kommeratt vara ett viktigt underlag i det fortsatta arbetet. Under hösten 2007kommer ett förslag till klassningssystem att presenteras.
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