Ursodeoxycholic acid (UDCA) is a bile acid which is used as pharmaceutical for the treatment of several diseases, such as cholesterol gallstones, primary sclerosing cholangitis or primary biliary cirrhosis. A potential chemoenzymatic synthesis route of UDCA comprises the two-step reduction of dehydrocholic acid to 12-keto-ursodeoxycholic acid (12-keto-UDCA), which can be conducted in a multienzymatic one-pot process using 3α-hydroxysteroid dehydrogenase (3α-HSDH), 7β-hydroxysteroid dehydrogenase (7β-HSDH), and glucose dehydrogenase (GDH) with glucose as cosubstrate for the regeneration of cofactor. Here, we present a dynamic mechanistic model of this one-pot reduction which involves three enzymes, four different bile acids, and two different cofactors, each with different oxidation states.
View Article and Find Full Text PDFTo overcome the problems of endpoint tests routinely required for EC50 determination, we utilized a novel automated high-content workstation and calculated a time-resolved EC50 value of MCF-7 mamma carcinoma cells treated with a pharmacologic agent. Measuring parameters were the cellular oxygen consumption and the extracellular acidification. These parameters were detected in real-time and label free with optochemical sensor spots in a modified 24-well sensor plate.
View Article and Find Full Text PDFThe DNA-chitosan polyplexes have attracted for some years now the attention of physical-chemists and biologists for their potential use in gene therapy, however, the correlation between the physicochemical properties of these polyplexes with their transfection efficiency remains still unclear. In a recent paper we demonstrated by means of DLS that the DNA-chitosan complexation is favored at acidic conditions considering that fewer amounts of chitosan were required to compact the DNA. As a second study, in the present work we analyze the influence of chitosan valence on the complexation and transfection of DNA.
View Article and Find Full Text PDFBackground: Persistent use of glucocorticoid drugs is associated with bone loss and increased fracture risk. Concurrent oral bisphosphonates increase bone mineral density and reduce frequency of vertebral fractures, but are associated with poor compliance and adherence. We aimed to assess whether one intravenous infusion of zoledronic acid was non-inferior to daily oral risedronate for prevention and treatment of glucocorticoid-induced osteoporosis.
View Article and Find Full Text PDFPre-clinical studies indicate that pharmacologic agents can augment fracture union. If these pharmacologic approaches could be translated into clinical benefit and offered to patients with osteoporosis or patients with other risks for impaired fracture union (e.g.
View Article and Find Full Text PDFUnlabelled: In a substudy of the HORIZON pivotal fracture trial, in which yearly intravenous zoledronic acid 5 mg was found to significantly reduce risk of various fracture types in patients with postmenopausal osteoporosis, 152 patients underwent bone biopsy. Zoledronic acid reduced bone turnover by 63% and preserved bone structure and volume, with evidence of ongoing bone remodeling in 99% of biopsies obtained.
Introduction: In the HORIZON pivotal fracture trial (PFT), enrolling 7,736 women with postmenopausal osteoporosis, three annual intravenous infusions of the bisphosphonate zoledronic acid (5 mg) significantly reduced morphometric vertebral, clinical vertebral, hip, and nonvertebral fractures by 70%, 77%, 41%, and 25%, respectively.
Unlabelled: To compare the prediction of hip fracture risk of several bone ultrasounds (QUS), 7062 Swiss women > or =70 years of age were measured with three QUSs (two of the heel, one of the phalanges). Heel QUSs were both predictive of hip fracture risk, whereas the phalanges QUS was not.
Introduction: As the number of hip fracture is expected to increase during these next decades, it is important to develop strategies to detect subjects at risk.
Rev Med Suisse Romande
February 2004
As an emerging alternative to DXA, there is a growing interest in the use of quantitative ultrasound (QUS) measurements for the non invasive assessment of fracture risk in the management of osteoporosis. While the potential of QUS in the management of osteoporosis have been highly recognized by the scientific community and granted by the majority of the international bone disease organizations, it becomes important to develop strategies how to use ultrasound clinically. Our paper is highlighting Swiss operational clinical propositions for 2 QUS devices sold in Switzerland, on how to use the QUS in the management of osteoporosis.
View Article and Find Full Text PDF