Time filter

Source Type

Kuopio, Finland

Yagodkin A.,University of Eastern Finland | Loschcke K.,University of Eastern Finland | Weisell J.,Biocenter Kuopio | Azhayev A.,University of Eastern Finland
Tetrahedron | Year: 2010

In the presence of aqueous trialkylammonium hydrogen carbonate, the Staudinger reaction leads to the intermediate formation of the corresponding isocyanate, which, in turn, reacts further with a nucleophilic reagent also present in the mixture and results in carbamoylation with good yield. On the basis of this reaction a practical carbamoylation procedure was devised and a comparative study on suitability of different solvents and phosphorus (III) derivatives for carbamoylation reaction was conducted. The versatility of the method was demonstrated by examples with different classes of nucleophilic compounds that included the aminomethyl resin and natural compounds that display poor solubility in organic solvents. © 2010 Elsevier Ltd. All rights reserved.

Milne R.L.,Genetic and Molecular Epidemiology Group | Gaudet M.M.,Yeshiva University | Spurdle A.B.,Queensland Institute of Medical Research | Fasching P.A.,University of California at Los Angeles | And 97 more authors.
Breast Cancer Research | Year: 2010

Introduction: Several common breast cancer genetic susceptibility variants have recently been identified. We aimed to determine how these variants combine with a subset of other known risk factors to influence breast cancer risk in white women of European ancestry using case-control studies participating in the Breast Cancer Association Consortium.Methods: We evaluated two-way interactions between each of age at menarche, ever having had a live birth, number of live births, age at first birth and body mass index (BMI) and each of 12 single nucleotide polymorphisms (SNPs) (10q26-rs2981582 (FGFR2), 8q24-rs13281615, 11p15-rs3817198 (LSP1), 5q11-rs889312 (MAP3K1), 16q12-rs3803662 (TOX3), 2q35-rs13387042, 5p12-rs10941679 (MRPS30), 17q23-rs6504950 (COX11), 3p24-rs4973768 (SLC4A7), CASP8-rs17468277, TGFB1-rs1982073 and ESR1-rs3020314). Interactions were tested for by fitting logistic regression models including per-allele and linear trend main effects for SNPs and risk factors, respectively, and single-parameter interaction terms for linear departure from independent multiplicative effects.Results: These analyses were applied to data for up to 26,349 invasive breast cancer cases and up to 32,208 controls from 21 case-control studies. No statistical evidence of interaction was observed beyond that expected by chance. Analyses were repeated using data from 11 population-based studies, and results were very similar.Conclusions: The relative risks for breast cancer associated with the common susceptibility variants identified to date do not appear to vary across women with different reproductive histories or body mass index (BMI). The assumption of multiplicative combined effects for these established genetic and other risk factors in risk prediction models appears justified. © 2010 Milne et al.; licensee BioMed Central Ltd.

Rytkonen J.,University of Eastern Finland | Rytkonen J.,Biocenter Kuopio | Miettinen R.,University of Eastern Finland | Miettinen R.,CNServices Ltd. | And 5 more authors.
Journal of Nanomaterials | Year: 2012

Carboxylic acid functionalized thermally hydrocarbonized porous silicon nanoparticles (UnTHCPSi-NP) were synthesized, and their opsonization and targeting properties were studied in vitro alongside with in vivo biodistribution. The carboxyl groups on UnTHCPSi were utilized to further functionalize the nanoparticles. In order to reduce the opsonization of the UnTHCPSi-NPs, different sized polyethylene glycol (PEG) were conjugated or adsorbed to the NPs surface. The latter approach, based on hydrophobic interaction, turned out to be more effective in reducing the opsonization and improving the stability of the nanoparticle suspension. The most abundant opsonins after plasma incubation were fibrinogen precursors and IgG. Furthermore, the targeting properties of UnTHCPSi-NPs were studied in vitro with antibodies against glutathione S-transferase (anti-GST). PEGylated NPs conjugated with anti-GST bound to GST-agarose in human plasma nearly 35-fold compared to control NPs, indicating that UnTHCPSi-NPs are suitable for targeting in physiological environment. The in vivo biodistribution in mice revealed that PEGylated UnTHCPSi-NPs, accumulate fast into the liver and the spleen, regardless of the reduced opsonization in vitro. However, autoradiography and transmission electron microscopy showed that majority of the NPs still remained in hepatic blood vessels and sinusoids suggesting a possibility to utilize them as a sustained release platform for payload molecules. © 2012 Jussi Rytkönen et al.

Raikkonen J.,University of Eastern Finland | Raikkonen J.,Biocenter Kuopio | Taskinen M.,University of Eastern Finland | Taskinen M.,Biocenter Kuopio | And 7 more authors.
Biochemical and Biophysical Research Communications | Year: 2011

A class of drugs successfully used for treatment of metabolic bone diseases is the nitrogen-containing bisphosphonates (N-BPs), which act by inhibiting the vital enzyme, farnesyl pyrophosphate synthase (FPPS), of the mevalonate pathway. Inhibition of FPPS by N-BPs results in the intracellular accumulation of isopentenyl pyrophosphate (IPP) and consequently induces the biosynthesis of a cytotoxic ATP analog (ApppI). Previous cell-free data has reported that N-BPs inhibit FPPS by time-dependent manner as a result of the conformational change. This associated conformational change can be measured as an isomerization constant (K isom) and reflects the binding differences of the N-BPs to FPPS. In the present study, we tested the biological relevance of the calculated K isom values of zoledronic acid, risedronate and five experimental N-BP analogs in the cell culture model. We used IPP/ApppI formation as a surrogate marker for blocking of FPPS in the mevalonate pathway.As a result, a correlation between the time-dependent inhibition of FPPS and IPP/ApppI formation by N-BPs was observed. This outcome indicates that the time-dependent inhibition of FPPS enzyme is a biologically significant mechanism and further supports the use of the K isom calculations for evaluation of the overall potency of the novel FPPS inhibitors. Additionally, data illustrates that IPP/ApppI analysis is a useful method to monitor the intracellular action of drugs and drug candidates based on FPPS inhibition. © 2011 Elsevier Inc.

Huhtala T.,University of Eastern Finland | Huhtala T.,Biocenter Kuopio | Kaikkonen M.U.,University of Eastern Finland | Kaikkonen M.U.,Ark Therapeutics Ltd | And 7 more authors.
Nuclear Medicine and Biology | Year: 2014

Viral vectors are central tools for gene therapy. Targeting of the vector to desired tissues followed by expression of the therapeutic gene forms one of the most critical points in effective therapy. In this study we used streptavidin-displaying lentivirus conjugated to biotinylated anti-epidermal growth factor receptor (EGFR) antibody (Cetuximab) to target vector specifically to ovarian tumors.Biodistribution of the targeted virus was studied in nude mice with orthotropic SKOV-3m human ovarian carcinoma xenografts. Radiolabeled antibodies were conjugated to streptavidin-displaying lentiviruses and biodistribution of the virus after the intravenous delivery to tumor-bearing mice was monitored up to 6. days using combined SPECT/CT imaging modality. Organ samples were collected post mortem and specific organ activities were measured. The integration of lentivirus vectors in collected tissue samples was analyzed using qPCR and the expression of green fluorescent protein (GFP)-transgene was tested by enzyme-linked immunosorbent assay.Our results showed that lentiviruses conjugated to Cetuximab (Cet-LV) or control human IgG (IgG-LV) accumulated mainly to the liver and spleen of the mice and to lower extent to lung, kidneys and tumors. Strikingly, in 50% of the mice injected with cetuximab-targeted lentivirus no tumor tissue was found, whereas the remaining half showed a significant decrease in tumor size. We hypothesize/present data that lentivirus-mediated INF-αβ production together with tumor targeting could function as an effective antitumor treatment. © 2014 Elsevier Inc.

Discover hidden collaborations