Evidence suggests that two regions of the striatum contribute differential support to instrumental response selection. The dorsomedial striatum (DMS) is thought to support expectancy-mediated actions, and the dorsolateral striatum (DLS) is thought to support habits. Currently it is unclear whether these regions store task-relevant information or just coordinate the learning and retention of these solutions by other brain regions.
View Article and Find Full Text PDFFood Addit Contam Part A Chem Anal Control Expo Risk Assess
March 2010
The occurrence of furan in some food products has already been known for a few decades, and it has been reconfirmed in more recent investigations that furan is present in a variety of foodstuffs. This list of products includes roasted coffee, which has been shown to generate furan as a result of the heat treatment at roasting which is applied to achieve the desired aroma and flavour profile of a roasted coffee. The objective of this study is to provide data to allow a better understanding of the available data of furan in coffee, the kinetics of furan generated during roasting, and to estimate the reduction of furan levels afterwards due to subsequent processing steps and consumer handling.
View Article and Find Full Text PDFWe explored a number of factors affecting the properties relevant to holographic optical data storage by using a two-color recording scheme in reduced, near-stoichiometric lithium niobate. Two-color, or photon-gated, recording is achieved by use of 852-nm information-carrying beams and 488-nm gating light. Readout at 852 nm is nondestructive, with a gating ratio of ~10(4).
View Article and Find Full Text PDFPhotorefractive gratings have been written in Pr:LiNbO(3) by use of a diode laser for writing and of filtered white light (390-520nm) as a gating source. The gating light increases the writing efficiency by more than 3 orders of magnitude, and the two-step writing process provides nondestructive readout. The material sensitivity for two-color writing rises strongly for gating wavelengths near the bandgap and approaches that of Fe-doped lithium niobate at power densities of a few watts per square centimeter.
View Article and Find Full Text PDFThis paper summarizes the progress made in understanding the formation of acrylamide in coffee, as well as potential reduction strategies, as presented during the joint CIAA/EC workshop on acrylamide, held in Brussels in March 2006. Currently, there are no concrete measures to reduce acrylamide concentrations in roast and ground coffee without appreciably changing the organoleptic properties of the product. Certain approaches, such as steam roasting, have been tried on a laboratory scale, albeit without affording a significant reduction.
View Article and Find Full Text PDFMol Nutr Food Res
November 2006
The content of acrylamide in coffee reaches a peak early in the roasting process, reflecting occurrence of both formation and destruction of acrylamide during roasting. Levels of acrylamide in the fully roasted product are a small fraction of the peak reached earlier. Glucose and moisture in green coffee do not show a significant correlation with acrylamide in roasted coffee.
View Article and Find Full Text PDFA new class of bisphosphonates containing nitrooxy NO-donor functions has been developed. The products proved to display affinity for hydroxyapatite. Injection of (99m)Tc-labeled derivatives 11 and 18 into male rats showed a preferential accumulation of the compounds in bone as compared to blood and muscles.
View Article and Find Full Text PDFTitanium is widely used in dental implants due to its suitable physical properties and its good biocompatibility. However, it is integrated into bone only passively, and the resulting fixation in the bone, which is necessary for the function, is mainly mechanical in nature. With the objective of increasing the chemical interaction between the implant and the bone tissue, several phosphonic acids were synthesized and grafted onto titanium disks.
View Article and Find Full Text PDFObjectives: To define the release of nitric oxide (NO), prostaglandin E2 (PGE2), and the neutral metalloproteinases (NMPs) in horses with subchondral cystic lesions (SCL) and to study bone resorption triggered by conditioned media of fibrous tissue of SCL in vitro.
Study Design: Equine explant cultures of fibrous tissue of SCL, and synovial membrane and articular cartilage of normal horses and horses affected with moderate and severe osteoarthritis were performed. NO, PGE2, and NMP concentrations of media samples were measured, and osteoclast formation and activation was studied in vitro.
Newborn NMRI strain mice were infected with Reilly-Finkel-Biskis (RFB) murine leukemia virus (MuLV), a murine leukemia virus that has been shown to induce lymphomas, osteosclerosis, and osteomas in susceptible strains of mice. Bone histomorphometry of the distal femoral metaphyses at 3-month intervals showed osteosclerosis 3 (100%), 6 (100%), and 9 (93%) months after infection. This was represented by significantly augmented cancellous bone mass and accompanied by distinct changes in bone architecture.
View Article and Find Full Text PDFThis single-center, open-label study examined the safety and potential effect of tiagabine on valproate pharmacokinetics under steady-state conditions. Twelve adult patients with seizures controlled by an individualized fixed dosage of valproate participated in the study. On day 1, the pharmacokinetics of valproic acid were determined.
View Article and Find Full Text PDFTwo single-center, open-label studies examined the potential effects of tiagabine on the pharmacokinetics and safety of carbamazepine and phenytoin at steady state. Twelve adult patients with seizures controlled by an individualized fixed dosage of antiepilepsy medication (carbamazepine or phenytoin) participated in each study. On day 1, the pharmacokinetics of the baseline antiepilepsy drug were determined.
View Article and Find Full Text PDFBackground: Because ritonavir, a human immunodeficiency virus (HIV) protease inhibitor, and clarithromycin, a macrolide antibiotic used in the treatment of disseminated infection caused by Mycobacterium avium complex, are likely to be administered concurrently for treatment of patients with HIV and acquired immunodeficiency syndrome (AIDS), the drug interaction potential of these 2 agents was evaluated. Both clarithromycin and ritonavir are metabolized to a significant extent through cytochrome P450-mediated biotransformation and are potential inhibitors of these enzymes.
Objective: To evaluate the pharmacokinetic effects of concomitant administration of multiple doses of ritonavir and clarithromycin.
To evaluate course and outcome of pregnancies in liver transplanted patients and to provide a brief summary on the development of these children, 22 pregnancies and 23 children (1 month-99 months old) of 16 patients who had been liver transplanted at our institution (mean interval from transplantation to pregnancy 43.1 months) were reviewed. Standard immunosuppressive regimen during pregnancy consisted of cyclosporine A (CyA), tacrolimus (FK), azathioprine (Aza) and/or a low-dose steroid therapy.
View Article and Find Full Text PDFWe report an open-label study of 25 children with complex partial seizures that assessed the pharmacokinetics and safety of a single dose of approximately 0.1 mg/kg tiagabine. The children received their usual individualized regimen of one concomitant antiepilepsy drug (AED) throughout the study.
View Article and Find Full Text PDFCurrent knowledge indicates that osteoblasts play an integral role in osteoclastic bone resorption through an osteoclast-stimulating activity produced by osteoblasts in response to resorption-promoting osteotropic factors. Previously, we have shown that the inhibitory action of the bisphosphonates on bone resorption in part is mediated by osteoblasts. The aim of the present study was to investigate whether the bisphosphonate-generated inhibition is due to these compounds decreasing the synthesis of the osteoclast-stimulating activity or is the result of osteoblasts synthesizing an osteoclast resorption inhibitor.
View Article and Find Full Text PDFParathyroid hormone-related protein (PTHrP) is synthesized by a variety of tumors and is thought to be the main cause of the clinical syndrome of humoral hypercalcemia of malignancy (HHM). In addition to its parathyroid hormone (PTH)-like actions, novel actions of PTHrP on placental calcium transport and inhibition of in vitro osteoclast activity have been demonstrated. The fact that osteoblasts act as mediators of osteoclastic bone resorption prompted us to investigate whether nontranformed, osteoblastlike cells produce PTHrP.
View Article and Find Full Text PDFGrowth factors, such as transforming growth factor beta (TGF-beta) and insulin-like growth factors (IGF) I and II, have been shown to exert anabolic effects on bone cells in vitro. Hormones, such as PTH and probably insulin and growth hormone, were recently shown to stimulate bone formation in vivo as well. The aim of the present study was to assess by northern blots, which were quantitated by densitometry, the effects of these anabolic growth factors and hormones in two osteogenic cell populations: CRP 10/30 cells, a clonal cell population derived from primary rat calvarial cells, and IRC 10/30-myc cells, which were established from CRP 10/30 by immortalization.
View Article and Find Full Text PDFBisphosphonates are generally considered to act on bone resorption by binding to bone mineral and subsequently inhibiting the activity of the osteoclasts which ingest them. This has been supported by the fact that bisphosphonates adsorbed on mineralized tissue inhibit the resorbing activity of isolated osteoclasts in vitro. However, the effectiveness of different bisphosphonates determined in this system does not reflect their relative potencies in vivo.
View Article and Find Full Text PDFOsteoblasts are known to produce osteoclast-stimulating activity (OSA). The aim of the current study was to relate the expression of OSA to the osteoblastic phenotype and examine its regulation by calciotropic hormones. The study was performed with the normal osteoblastic cell clone CRP 10/30 and the preosteoblastic clone CRP 4/7.
View Article and Find Full Text PDFThe human-derived procalcitonin amino-terminal cleavage peptide, N-proCT has previously been shown to act mitogenically on isolated chicken and human osteoblast-like cells and on the human osteosarcoma cell line U-2 OS. We have examined the effect of N-proCT on growth and phenotype of cloned rat osteoblastic and preosteoblastic cells. Neither cell growth nor the phenotype (ALP, PTH response) of either cell type was significantly changed by the procalcitonin cleavage peptide.
View Article and Find Full Text PDFOsteoblastic cells were cloned by culturing rat calvariae cells in agarose in the presence of TGF-beta and EGF. Two bone cell lines were established by immortalizing such an osteoblastic clonal cell population by the introduction of the avian v-mycOK10 gene in the form of a mouse ecotropic retrovirus. Although originating from the same clonal cell population, the two lines exhibited somewhat differing properties.
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