| 1. |
- Fall, Tove, 1979-, et al.
(författare)
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Gestational Diabetes Mellitus in 13 Dogs
- 2008
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Ingår i: Journal of Veterinary Internal Medicine. - : Wiley. - 0891-6640 .- 1939-1676. ; 22:6, s. 1296-1300
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Tidskriftsartikel (refereegranskat)abstract
- Background: There are few reports on the clinical appearance, prognosis, and risk factors for gestational diabetes mellitus (GDM) in dogs. Objective: To describe the clinical characteristics of GDM in dogs. Animals: Thirteen dogs with GDM. Methods: Retrospective study. Medical records were reviewed and owners and referring veterinarians were contacted for follow-up information. Results: Nordic Spitz breeds (11/13 dogs) were overrepresented in the case material. Diagnosis was established at a median of 50 days after mating (range, 32–64). Median glucose concentration at diagnosis was 340 mg/dL (18.9 mmol/L) (range, 203–587). One dog was euthanized at diagnosis, 5 bitches were treated with insulin until whelping, and in 7 dogs, pregnancy was terminated within 4 days of diagnosis. One dog died after surgery. Tight glycemic control was not achieved in any of the insulin-treated dogs during pregnancy. Diabetes mellitus (DM) resolved in 7 dogs at a median of 9 days after the end of their pregnancies and DM was permanent in 4 dogs. Puppy mortality was increased compared with offspring of healthy dams. Conclusion: This report suggests that GDM affects mainly middle-aged bitches in the 2nd half of pregnancy with a breed predisposition toward Nordic Spitz breeds. GDM may resolve within days to weeks after pregnancy has ended. Further research is needed to investigate optimal treatment regimens for dogs with GDM and risk factors for unsuccessful outcome.
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| 2. |
- Sundqvist, A-K, et al.
(författare)
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Unequal contribution of sexes in the origin of dog breeds.
- 2006
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Ingår i: Genetics. - 0016-6731. ; 172:2, s. 1121-8
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Tidskriftsartikel (refereegranskat)abstract
- Department of Evolutionary Biology, Uppsala University, Sweden. anna-karin.sundqvist@ebc.uu.seDogs (Canis familiaris) were domesticated from the gray wolf (Canis lupus) at least 14,000 years ago, and there is evidence of dogs with phenotypes similar to those in modern breeds 4000 years ago. However, recent genetic analyses have suggested that modern dog breeds have a much more recent origin, probably <200 years ago. To study the origin of contemporaneous breeds we combined the analysis of paternally inherited Y chromosome markers with maternally inherited mitochondrial DNA and biparentally inherited autosomal microsatellite markers in both domestic dogs and their wild ancestor, the gray wolf. Our results show a sex bias in the origin of breeds, with fewer males than females contributing genetically, which clearly differs from the breeding patterns in wild gray wolf populations where both sexes have similar contributions. Furthermore, a comparison of mitochondrial DNA and Y chromosome diversity in dog groups recognized by the World Canine Organization, as well as in groups defined by the breeds' genetic composition, shows that paternal lineages are more differentiated among groups than maternal lineages. This demonstrates a lower exchange of males than of females between breeds belonging to different groups, which illustrates how breed founders may have been chosen.
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| 3. |
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| 4. |
- Hedhammar, My, Professor, 1975-, et al.
(författare)
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Structural properties of recombinant nonrepetitive and repetitive parts of major ampullate spidroin 1 from Euprosthenops australis : implications for fiber formation
- 2008
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Ingår i: Journal of Biotechnology. - : American Chemical Society (ACS). - 0168-1656 .- 1873-4863. ; 47:11, s. 3407-17
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Tidskriftsartikel (refereegranskat)abstract
- Spider dragline silk proteins, spidroins, have a tripartite composition; a nonrepetitive N-terminal domain, a central repetitive region built up from many iterated poly-Ala and Gly rich blocks, and a C-terminal nonrepetitive domain. It is generally believed that the repetitive region forms intermolecular contacts in the silk fibers, while precise functions of the terminal domains have not been established. Herein, thermal, pH, and salt effects on the structure and aggregation and/or polymerization of recombinant N- and C-terminal domains, a repetitive segment containing four poly-Ala and Gly rich coblocks, and combinations thereof were studied. The N- and C-terminal domains have mainly alpha-helical structure, and interestingly, both form homodimers. Dimerization of the end domains allows spidroin multimerization independent of the repetitive part. Reduction of an intersubunit disulfide in the C-terminal domain lowers the thermal stability but does not affect dimerization. The repetitive region shows helical secondary structure but appears to lack stable folded structure. A protein composed of this repetitive region linked to the C-terminal domain has a mainly alpha-helical folded structure but shows an abrupt transition to beta-sheet structures upon heating. At room temperature, this protein self-assembles into macroscopic fibers within minutes. The secondary structures of none of the domains are altered by pH or salt. However, high concentrations of phosphate affect the tertiary structure and accelerate the aggregation propensity of the repetitive region. Implications of these results for dragline spidroin behavior in solution and silk fiber formation are discussed.
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| 5. |
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| 6. |
- Stark, M., et al.
(författare)
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Macroscopic fibers self-assembled from recombinant miniature spider silk proteins
- 2007
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Ingår i: Biomacromolecules. - : American Chemical Society (ACS). - 1525-7797 .- 1526-4602. ; 8:5, s. 1695-1701
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Tidskriftsartikel (refereegranskat)abstract
- Strength, elasticity, and biocompatibility make spider silk an attractive resource for the production of artificial biomaterials. Spider silk proteins, spidroins, contain hundreds of repeated poly alanine/glycine-rich blocks and are difficult to produce recombinantly in soluble form. Most previous attempts to produce artificial spider silk fibers have included solubilization steps in nonphysiological solvents. It is here demonstrated that a miniature spidroin from a protein in dragline silk of Euprosthenops australis can be produced in a soluble form in Escherichia coli when fused to a highly soluble protein partner. Although this miniature spidroin contains only four poly alanine/glycine-rich blocks followed by a C-terminal non-repetitive domain, meter-long fibers are spontaneously formed after proteolytic release of the fusion partner. The structure of the fibers is similar to that of dragline silks, and although self-assembled from recombinant proteins they are as strong as fibers spun from redissolved silk. Moreover, the fibers appear to be biocompatible because human tissue culture cells can grow on and attach to the fibers. These findings enable controlled production of high-performance biofibers at large scale under physiological conditions.
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