1. |
|
|
2. |
- Hopfgarten, Johan, et al.
(author)
-
Gene expression analysis of human islets in a subject at onset of type 1 diabetes
- 2014
-
In: Acta Diabetologica. - : Springer Science and Business Media LLC. - 0940-5429 .- 1432-5233. ; 51:2, s. 199-204
-
Journal article (peer-reviewed)abstract
- Swollen islet cells have been repeatedly described at onset of type 1 diabetes, but the underlying mechanism of this observation, termed hydropic degeneration, awaits characterization. In this study, laser capture microdissection was applied to extract the islets from an organ donor that died at onset of type 1 diabetes and from an organ donor without pancreatic disease. Morphologic analysis revealed extensive hydropic degeneration in 73 % of the islets from the donor with type 1 diabetes. Expression levels of genes involved in apoptosis, ER stress, beta cell function, and inflammation were analyzed in isolated and laser-captured islets by qPCR. The chemokine MCP-1 was expressed in islets from the donor with type 1 diabetes while undetectable in the control donor. No other signs of inflammation were detected. There were no signs of apoptosis on the gene expression level, which was also confirmed by negative immunostaining for cleaved caspase-8. There was an increased expression of the transcription factor ATF4, involved in transcription of ER stress genes, in the diabetic islets, but no further signs of ER stress were identified. In summary, on the transcription level, islets at onset of type 1 diabetes in which many beta cells display hydropic degeneration show no obvious signs of apoptosis, ER stress, or inflammation, supporting the notion that these cells are responding normally to high glucose and eventually succumbing to beta cell exhaustion. Also, this study validates the feasibility of performing qPCR analysis of RNA extracted from islets from subjects with recent onset of T1D and healthy controls by laser capture microdissection.
|
|
3. |
- Ingvast Larsson, Carina, et al.
(author)
-
Clinical pharmacology of methadone in dogs
- 2010
-
In: Veterinary Anaesthesia and Analgesia. - : Elsevier BV. - 1467-2987 .- 1467-2995. ; 37:1, s. 48-56
-
Journal article (peer-reviewed)abstract
- Objective: To investigate the pharmacokinetics and effects of methadone on behaviour and plasma concentrations of cortisol and vasopressin in healthy dogs. Study design Randomized, cross-over, experimental trial. Animals Nine adult dogs (beagle and beagle cross breeds), four males and five females. Methods Methadone hydrochloride, 0.4 mg kg-1, was administered intravenously (IV) and subcutaneously (SC) with a crossover design. Drug and hormone analyses in plasma were performed using Liquid Chromatography-Electrospray Ionization-Tandem Mass Spectrometry and radioimmunoassay respectively. Behavioural data were collected using a standardized protocol. Results After IV administration, the plasma concentration of methadone at 10 minutes was 82.1 +/- 9.2 ng mL-1 (mean +/- SD), the terminal half-life was 3.9 +/- 1.0 hours, the volume of distribution 9.2 +/- 3.3 L kg-1 and plasma clearance 27.9 +/- 7.6 mL minute-1 kg-1. After SC administration, time to maximal plasma concentration was 1.26 +/- 1.04 hours and maximal plasma concentration of methadone was 23.9 +/- 14.4 ng mL-1, the terminal half-life was 10.7 +/- 4.3 hours and bioavailability was 79 +/- 22%. Concentrations of both cortisol and vasopressin were increased for an hour following IV methadone. The observed behavioural effects of methadone were decreased licking and swallowing and an increase in whining after SC administration. The latter finding is notable as it can be misinterpreted as pain when methadone is used as an analgesic. Conclusion and clinical relevance When methadone was administered by the SC route, the half-life was longer, but the individual variation in plasma concentrations was greater compared with IV administration. Increased frequency of whining occurred after administration of methadone and may be a drug effect and not a sign of pain. Cortisol and vasopressin concentrations in plasma may not be suitable for evaluating analgesia after methadone treatment.
|
|
4. |
- Skog, Oskar, et al.
(author)
-
Evaluation of RT-PCR and immunohistochemistry as tools for detection of enterovirus in the human pancreas and islets of Langerhans
- 2014
-
In: Journal of Clinical Virology. - : Elsevier BV. - 1386-6532 .- 1873-5967. ; 61:2, s. 242-247
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Enteroviruses have been implicated in the etiology of type 1 diabetes, supported by immunoreactivity of enteroviral protein in islets, but presence of enteroviral genome has rarely been reported. Failure to detect enterovirus with RT-PCR has been attributed to the possible presence of PCR inhibitors and that only few cells are infected.OBJECTIVES: The aim of this study was to evaluate strategies for detection of enterovirus in human islets.STUDY DESIGN: A scenario was modeled with defined infected islets among a large number of uninfected pancreatic cells and the sensitivity of immunohistochemistry and PCR for detection of enterovirus was evaluated.RESULTS: Enterovirus was detected with PCR when only one single human islet, infected in vitro with a low dose of virus, was mixed with an uninfected pancreatic biopsy. Enterovirus could not be detected by immunohistochemistry under the same conditions, demonstrating the superior sensitivity of PCR also in pancreatic tissue with only a small fraction of infected cells. In addition, we demonstrate that pancreatic cell culture supernatant does not cause degradation of enterovirus at 37°C, indicating that under normal culture conditions released virus is readily detectable. Utilizing PCR, the pancreases of two organ donors that died at onset of type 1 diabetes were found negative for enterovirus genome despite islet cells being positive using immunohistochemistry.CONCLUSIONS: These data suggest that PCR should be the preferred screening method for enterovirus in the pancreas and suggest cautious interpretation of immunostaining for enterovirus that cannot be confirmed with PCR.
|
|
5. |
|
|
6. |
|
|
7. |
|
|
8. |
|
|