Browsing by Author "Larsen, Stig"
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Item Increased serum osteocalcin levels and vitamin K status by daily cheese intake(Medip Academy, 2020-04) Lundberg, Helge E.; Holand, Trond; Holo, Helge; Larsen, StigBackground:Cheese is a major source of long-chained vitamin K2 variants. How intake of vitamin K2 rich cheese affects vitamin K and osteocalcin has not been studied. The aim was to establish a maximum efficacy dose (MED) after daily intake of vitamin K2-rich cheese (Jarlsberg®) based on increase in ratio between carboxylated and undercarboxylated osteocalcin during a five-week diet.Methods:20 healthy healthy volunteers (HV) were recruited. The daily intake of Jarlsberg®cheese in the study varied from 20 to 152g. Clinical investigation was performed initially and after three, four and five weeks with measurement of vital signs, hematological and biochemical variables, carboxylatedand undercarboxylated osteocalcin and vitamin K. The ratio OR=carboxylated/undercarboxylated osteocalcin was the main variable.Results:The MED decreased with treatment duration and was estimated to 57 g/day (95% CI: 47-67)after five weeks diet, resulting in a mean OR increase of 30% (95% CI: 23.8-36.8). Both OR and serum osteocalcin followed a quadratic dose response curve. For osteocalcin,a maximal increase of 46% was estimated at 59 g/day for five weeks. The serum content of long-chained vitamin K2 increased significantly with increasing cheese dose. The increase were mainly obtained the first three weeks and kept unchanged the following two weeks. The cheese doses close to the MED caused nearly significant reductionsin total cholesterol, LDL-cholesterol, the LDL/HDL ratio and significant reduction in the blood pressures after five weeks diet (p?0.05). Conclusions: MED of Jarlsberg® cheese was estimated to 57g/day. Daily intake of Jarlsberg®cheese increasedthe osteocalcin level, vitamin K2andpositively affected the lipid patterns and blood pressure.Item Prevalence of hepatitis B & hepatitis C virus infections in potential blood donors in rural Vietnam.(2012-07) Viet, Le; Lan, Nguyen Thi Ngoc; Ty, Phung Xuan; Björkvoll, Björn; Hoel, Hedda; Gutteberg, Tore; Husebekk, Anne; Larsen, Stig; Skjerve, Eystein; Husum, HansBackground & objectives: Safe blood and blood products should be offered to all patients in need for blood transfusion. The objectives of the present study were to establish prevalence estimates for hepatitis B and hepatitis C virus infections as a foundation for safe blood transfusion in rural Vietnam, and to check the accuracy of the laboratory analysis used for hepatitis testing of blood donors in Vietnam. Methods: A cross-sectional study was conducted in two rural communities in Quang Tri, Vietnam. A total of 1,200 blood samples collected from potential blood donors were tested by an enzyme immunoassay technique (EIA) for detection of hepatitis surface antigen (HBsAg), antibodies to hepatitis B core antigen (anti-HBc), and antibodies to hepatitis C antigen (anti-HCV). The EIA test outcome was validated by a chemiluminescent micro particle immunoassay technique (CMIA). Results: The prevalence of HBsAg and anti-HBc in the study population was 11.4 per cent (95% CI 9.6 - 13.2) and 51.7 per cent (95% CI 48.8 - 54.5), respectively, the prevalences being higher in males than females. The prevalence of anti-HCV was 0.17 per cent. The test agreement between the EIA and CMIA techniques was high both for HBsAg detection (κ = 0.91; 95% CI: 0.83 - 0.99) and for anti-HBc detection (κ = 0.89; 95% CI 0.81 - 0.97). Compared to CMIA results, the positive and negative predictive values of the EIA tests were found to be 94.9 per cent (95% CI 87.5 - 98.6) and 97.5 per cent (95% CI 86.8 - 99.9) for HBsAg, and 92.4 per cent (95% CI 84.2 - 97.2) and 100 per cent (95% CI 91.2 - 100) for anti-HBc. Interpretation & conclusions: The study shows that hepatitis B virus infection is endemic in rural areas of Vietnam and that almost half of the population is or has been infected. Hepatitis C infection is rare, but false negative test results cannot be ruled out. Also, the results indicate that the EIA performance in blood donor screening in Vietnam may be sub-optimal, missing 2.5 per cent of hepatitis B virus carriers and falsely excluding more than 7 per cent of blood donors. As the prevalence of hepatitis B infection is high, occult hepatitis B infection may represent a threat to safe blood transfusion. Therefore, nucleic acid amplification testing for HBV should be considered for blood donor screening in Vietnam.Item Randomized response surface pathway design with skewed starting point and stochastic dose window(Medip Academy, 2020-01) Trond, Holand; Øystein, Evensen; Dewi, Sagita; Larsen, StigBackground:The aim was to introduce response surface pathway(RSP)-design with skewed starting value and stochastic dose-window to estimate optimal efficacy dose (OED) of BP-C2 after IL-1? stimulation in Atlantic salmon.Methods:54 healthy smolt of Atlantic salmon between 50 and 100g before habituated to saltwater were included. The study was conducted as a one-dimensional, randomized between-patient three-level RSP designed trial with one interventional-and one response variable and odd outcomes. The interventional variable was intraperitoneal injected BPC2 with skewed starting dose of 0.10 mg/100g related to the initial dose-window <0.02-0.5 mg/100g. The response variable was the Ct-value of mRNA IL-1? expression 24 hours after injection.Results:Skewed starting value of 0.10 mg/100g was chosen in the first design-level with a dose-window of <0.0-0.20].The three smolt obtained a reduction in Ct-value above 15%, and the dose-window adjusted with the lower boundary equals the previous dose. The five smolt at second esign-level received 0.16 mg/100g with a dose-window [0.10-0.22]. Four smolt obtained above 15% and one of 0.5% reduction in cycle threshold (Ct)-value. Six smolt in the third design-level received 0.21 mg/100g and one 0.16 mg/100g. The mean Ct-value was reduced from 30.0 in the nstimulated situation to 25.0, 24.8 and 26.4 after BP-C2 stimulation of 0.10, 0.16 and 0.21mg/100g, respectively. The OED of BP-C2 related to IL-1? was estimated to 0.14 mg/100g.Conclusions: Skewed starting value in the initial dose-window made the K-adjustment factor and dose-window stochastic. The RSP-procedure works in accordance to the expectation and estimated OED of BP-C2 sufficiently.