Induction of annexin-1 at transcriptional and post-transcriptional level in rat brain by methylprednisolone and the 21-aminosteroid U74389F

Brain tissue of rats pretreated with methylprednisolone or with the 21-aminosteroid U74389F, and that of untreated control rats, was assessed for the expression of annexin-1 (Anx-1) and the transcription of its mRNA. For this purpose Anx-1 cDNA was amplified and simultaneously a T7-RNA-polymerase promoter was incorporated into the cDNA using a polymerase chain reaction (PCR). Then digoxigenin-11-UTP was incorporated into the transcribed cRNA with T7-RNA-polymerase. With this probe in situ hybridization was carried out on sections of the brain. The probe was visualized by an immunoassay using an antidigoxigenin antibody conjugate. Anx-1 protein was assessed by means of immunohistochemistry using a polyclonal antibody. The various brain areas of the control animals showed an appreciable amount of Anx-1 at mRNA or protein level; on the other hand, the animals which had been pretreated with either steroid, showed a more intense Anx-1 mRNA signal than the controls in many areas. In the pretreated animals Anx-1 immunostaining was unchanged in cortex, basal ganglia, amygdala and septum, but more intense in hippocampus, hypothalamus and thalamus. In ependyma, choroid plexus, meninges, and vascular walls there was no Anx-1 mRNA transcription detectable. An opposite profile was shown by the Anx-1 immunoreactivity, the protein was present in control animals as well as the steroid-pretreated animals, suggesting that here the protein was either from systemic origin, or has diffused from adjacent structures. The results indicated that Anx-1 mRNA transcription is upregulated by either steroid, and that in the untreated animals there is a resting level of Anx-1 mRNA transcription, presumably reflecting physiological influences on Anx-1 expression

Novel pyridinium surfactants for efficient, nontoxic in vitro gene delivery

Novel, double-chained pyridinium compounds have been developed that display highly efficient DNA transfection properties. The transfection efficiency of several of these compounds is enhanced by an order of magnitude, when compared with the transfection efficiency accomplished with the widely used cationic lipid system, lipofectin. Most importantly, the pyridinium compounds were found to be essentially nontoxic toward cells. Using various reporter genes, such as beta-galactosidase and pNEO (a gene construct that renders cells resistent to antibiotic derivatives of neomycin like G418), we demonstrate that the enhanced efficiency relates to the fact that a relative higher number of cells in the population is transfected (approximately 50% in the case of COS cells) by the pyridinium derivatives, whereas the delivery of DNA per cell is also enhanced. Furthermore, application of the pyridinium derivatives shows little cellular preference in their ability to transfect cells. By systematically modifying the structure of the pyridinium amphiphile, i.e., by changing either the headgroup structure or the alkyl chains, some insight was obtained that may lead to unraveling the mechanism of amphiphile-mediated transfection, and thus to protocols that further optimize the carrier properties of the amphiphile. Our results reveal that unsaturated alkyl chains enhance the transfection properties of the pyridinium-based amphiphiles. Preliminary experiments suggest that the structure-dependent improvement of transfection efficiency, when comparing pyridinium derivatives with lipofectin, likely relates to the mechanism of delivery rather than the packaging of the amphiphile/DNA complex

Leukocyte Counts, Myeloperoxidase, and Pregnancy-Associated Plasma Protein A as Biomarkers for Cardiovascular Disease: Towards a Multi-Biomarker Approach

We evaluated leukocyte counts and levels of CRP, fibrinogen, MPO, and PAPP-A in patients with stable and unstable angina pectoris, acute myocardial infarction, and healthy controls. All biomarkers were analyzed again after 6 months. Leukocyte counts and concentrations of fibrinogen, CRP, MPO, and PAPP-A were significantly increased in patients with acute myocardial infarction. Leukocyte counts and concentrations of MPO were significantly increased in patients with unstable angina pectoris compared with controls. After 6 months, leukocyte counts and MPO concentrations were still increased in patients with acute myocardial infarction when compared to controls. Discriminant analysis showed that leukocyte counts, MPO, and PAPP-A concentrations classified study group designation for acute coronary events correctly in 83% of the cases. In conclusion, combined assessment of leukocyte counts, MPO, and PAPP-A was able to correctly classify acute coronary events, suggesting that this could be a promising panel for a multibiomarker approach to assess cardiovascular risk

Targeted DNA Methylation by a DNA Methyltransferase Coupled to a Triple Helix Forming Oligonucleotide To Down-Regulate the Epithelial Cell Adhesion Molecule

The epithelial cell adhesion molecule (EpCAM) is a membrane glycoprotein that has been identified as a marker of cancer-initiating cells. EpCAM is highly expressed on most carcinomas, and transient silencing of EpCAM expression leads to reduced oncogenic potential. To silence the EpCAM gene in a persistent manner via targeted DNA methylation, a low activity mutant (C141S) of the CpG-specific DNA methyltransferase M.SssI was coupled to a triple-helix-forming oligonucleotide (TFO−C141S) specifically designed for the EpCAM gene. Reporter plasmids encoding the green fluorescent protein under control of different EpCAM promoter fragments were treated with the TFO−C141S conjugate to determine the specificity of targeted DNA methylation in the context of a functional EpCAM promoter. Treatment of the plasmids with TFO−C141S resulted in efficient and specific methylation of the targeted CpG located directly downstream of the triple helix forming site (TFS). No background DNA methylation was observed neither in a 700 bp region of the EpCAM promoter nor in a 400 bp region of the reporter gene downstream of the TFS. Methylation of the target CpG did not have a detectable effect on promoter activity. This study shows that the combination of a specific TFO and a reduced activity methyltransferase variant can be used to target DNA methylation to predetermined sites with high specificity, allowing determination of crucial CpGs for promoter activity

Telomere length in breast cancer patients before and after chemotherapy with or without stem cell transplantation

High-dose chemotherapy and peripheral blood stem cell transplantation (PBSCT) may accelerate telomere length loss in haematopoietic stem cells. As data including pre-and post-treatment samples are lacking, we studied leukocyte telomere length and telomerase activity before and after treatment in breast cancer patients randomized to receive 5 adjuvant courses FEC (5-FU, epirubicin and cyclophosphamide) (n= 17), or 4 × FEC followed by high-dose cyclophosphamide, thiotepa, carboplatin and autologous PBSCT (n= 16). Haemoglobin, MCV, leukocyte-and platelet numbers were assessed prior to (t0), 5 months after (t1) and 9 months after chemotherapy (t2); these parameters were decreased at t1 and t2 compared to t0(high-dose: all parameters; standard-dose: leukocytes and platelets), and all parameters were lower after high-dose than standard-dose treatment at t1. Paired individual leukocyte samples of t0 and t1 showed telomere length change (determined by telomere restricted fragment (TRF) assay) ranging from +0.8 to –2.2 kb, with a decreased TRF length in 9 patients of both groups. Telomerase activity (determined by TRAP assay) was below detection limit in leukocyte samples of t0 and t1. Thus, standard-and high-dose chemotherapy negatively affect haematological reconstitution in this setting. In individual patients, telomere length can be remarkably changed following haematological proliferative stress after treatment. © 2001 Cancer Research Campaign www.bjcancer.co

Endothelium-targeted delivery of dexamethasone by anti-VCAM-1 SAINT-O-Somes in mouse endotoxemia

Microvascular endothelial cells play a pivotal role in the pathogenesis of sepsis-induced inflammatory responses and multiple organ failure. Therefore, they represent an important target for pharmacological intervention in the treatment of sepsis. Glucocorticosteroids were widely used in the treatment of sepsis but vast evidence to support their systemic use is lacking. The limited effects of glucocorticoids in the treatment of sepsis may be explained by differential effects of drug initiated NF-κB inhibition in different cell types and insufficient drug delivery in target cells. The current study aimed therefore to investigate the effects of an endothelial targeted delivery of dexamethasone in a mouse model of endotoxemia induced by two consecutive i.p. injections of lipopolysaccharide (LPS). To achieve endothelial cell specific delivery of dexamethasone, we modified SAINT-O-Somes, a new generation of liposomes that contain the cationic amphiphile SAINT-C18 (1-methyl-4-(cis-9-dioleyl) methyl-pyridinium chloride, with antibodies against vascular cell adhesion molecule-1 (VCAM-1). In LPS challenged mice, the systemic administration of free dexamethasone had negligible effects on the microvascular inflammatory endothelial responses. Dexamethasone-loaded anti-VCAM-1 SAINT-O-Somes specifically localized at VCAM-1 expressing endothelial cells in the microvasculature of inflamed organs. This was associated with a marginal attenuation of the expression of a few pro-inflammatory genes in kidney and liver, while no effects in the lung were observed. This study reveals that, although local accumulation of the targeted drug was achieved, endothelial targeted dexamethasone containing anti-VCAM-1 SAINT-O-Somes exhibited marginal effects on inflammatory endothelial cell activation in a model of endotoxemia. Studies with more potent drugs encapsulated into anti-VCAM-1 SAINT-O-Somes will in the future reveal whether this delivery system can be further developed for efficacious endothelial directed delivery of drugs in the treatment of sepsis

Oxidative phosphorylation in human muscle in patients with ocular myopathy and after general anaesthesia

Abstract The fuel preference of human muscle mitochondria has been given. Substrates which are oxidized with low velocity cannot be used to detect defects in oxidative phosphorylation. After general anaesthesia, the oxygen uptake with the different substrates is much lower than after local analgesia. The latter was therefore used in the subsequent study. In 15 out of 18 patients with ocular myopathy, defects in oxidative phosporylation could be detected in isolated muscle mitochondria prepared from freshly biopsied tissue. Measurement of the activity of segments of the respiratory chain in homogenate from frozen muscle showed no, or minor defects. In two of these patients showing exercise intolerance, decreased oxidation of NAD+-linked substrates and apparently normal mitochondrial DNA, further study revealed deficiency of pyruvate dehydrogenase in a girl with ptosis and a high Km of complex I for NADH in a man. Both patients responded to vitamin therapy

Establishment of Protein Delivery Systems Targeting Podocytes

Podocytes are uniquely structured cells that are critical to the kidney filtration barrier. Their anatomic location on the outer side of the glomerular capillaries expose podocytes to large quantities of both plasma and urinary components and thus are reachable for drug delivery. Recent years have made clear that interference with podocyte-specific disease pathways can modulate glomerular function and influence severity and progression of glomerular disease.Here, we describe studies that show efficient transport of proteins into the mammalian cells mouse 3T3 fibroblasts and podocytes, utilizing an approach termed profection. We are using synthetic lipid structures that allow the safe packing of proteins or antibodies resulting in the subsequent delivery of protein into the cell. The uptake of lipid coated protein is facilitated by the intrinsic characteristic of cells such as podocytes to engulf particles that are physiologically retained in the extracellular matrix. Profection of the restriction enzyme MunI in 3T3 mouse fibroblasts caused an increase in DNA degradation. Moreover, purified proteins such as beta-galactosidase and the large GTPase dynamin could be profected into podocytes using two different profection reagents with the success rate of 95-100%. The delivered beta-galactosidase enzyme was properly folded and able to cleave its substrate X-gal in podocytes. Diseased podocytes are also potential recipients of protein cargo as we also delivered fluorophore labeled IgG into puromycin treated podocytes. We are currently optimizing our protocol for in vivo profection.Protein transfer is developing as an exciting tool to study and target highly differentiated cells such as podocytes

Erforschung von biokompatiblen und korrosionsbestandigen Beschichtungen, die auf Titanlegierung Vt6 durch Elektroerosivemetallbearbeitung aufgetragen werden

В статье рассмотрены фазовый и химико-элементный составы покрытия для ортопедии и дентальной медицины, нанесенного на титановый сплав ВТ6методом электроискровой обработки металлов с целью предотвращения попадания с поверхности сплава в организм человека химических элементов, оказывающих токсическое воздействие