0000000000021913
AUTHOR
Indrikis Muiznieks
Correlation of plasmid DNA supercoiling and the efficiency of plasmid gene transcription
The comparison of knee osteoarthritis treatment with single-dose bone marrow-derived mononuclear cells vs. hyaluronic acid injections
Objective: The aim of this study was to compare treatment methods of the knee joint degenerative osteoarthritis, using autologous bone marrow-derived mononuclear cells and hyaluronic acid injections and observe prevalence of adverse effects in both groups. Materials and methods: A prospective randomized controlled clinical trial was carried out. The analysis of pain and changes in osteoarthritis symptoms after a single intra-articular bone marrow-derived mononuclear cell injection into the knee joint in the Kellgren– Lawrence stage II–III osteoarthritis during the 12-month period were performed. The results were compared with the control group treated routinely by hyaluronic acid injections…
Visible Photoluminescence of Variable-Length Zinc Oxide Nanorods Embedded in Porous Anodic Alumina Template for Biosensor Applications
Zinc oxide (ZnO) and porous anodic aluminum oxide (PAAO) are technologically important materials, rich with features that are of interest in optical applications, for example, in light-emitting and sensing devices. Here, we present synthesis method of aligned ZnO nanorods (NR) with 40 nm diameter and variable length in 150 to 500 nm range obtained by atomic layer deposition (ALD) of ZnO in pores of continuously variable thickness PAAO. The relative intensity of yellow (1.99 eV), green (2.35 eV), and blue (2.82 eV) photoluminescence (PL) components originating from the different types of defects, varied with non-monotonic dependency on the composite film thickness with a Fabry–Pérot like mod…
Treatment of experimental autoimmune encephalomyelitis with adenylate deaminase from Penicillium lanoso-viride.
The effect of intramuscularly administered immunomodulator, adenylate deaminase (E.C. 3.5.4.6), from Penicillium lanoso-viride on the clinical score of acute experimental autoimmune encephalomyelitis (EAE), a T cell-mediated autoimmune disease, was examined by inoculation of guinea pigs with rabbit brain and spinal cord homogenate (encephalitogen) and complete Freund's adjuvant. Adenylate deaminase (ADA) was effective in delaying the onset of clinical disease. ADA inhibited the severity of EAE. There was a significant decrease in clinical signs. A decrease in the number of morbid and dead animals was observed. Of ADA treated animals, 50-80% developed no clinical manifestations of EAE. The o…
Monitoring seasonal changes in microbial populations of spruce forest soil of the Northern Temperate Zone
Soil microbial populations in the Northern Temperate Zone have been poorly studied in comparison with extreme environments. The aim of the work was to study the seasonal changes in the microbial populations of spruce forest soil of the Northern Temperate Zone using classical methods of microbiology and molecular biology. Upper horizons in two Picea abies stands on sod- podzolic and illuvial humus podzol soil were analysed. Sampling was done monthly over a period of twelve months (May 2009-April 2010). Microbial communities in both experimental plots showed different responses to the analysed environmental factors. In the sod-podzolic soil only the fungal DNA amount was significantly higher …
Protective effect of adenylate deaminase (from Penicillium lanoso-viride) against acute infections in mice
We examined the effects of the immunomodulator-adenylate deaminase (E.C. 3.5.4.6) from Penicillium lanoso-viride on experimental mice infections. Prophylactic intraperitoneal administration of adenylate deaminase (ADA) increased survival time and numbers of survivors after infection with Salmonella typhimurium, Pseudomonas aeruginosa and influenza A (H3N2) virus. Protection against influenza virus after intranasal ADA application was also observed. The influence of ADA was time and dose dependent. The most pronounced protection was obtained by administration of 3 U ADA/mice 24 h prior to infection. ADA had no antibiotic effect against these bacterial strains. Protective effects of ADA were …
Identification of monocyte subpopulations and signaling pathways responsible for the immune response to fungal immunomodulatory glycoprotein AMPD
Electrochemically etched sharp aluminium probes with nanoporous aluminium oxide coatings: demonstration of addressed DNA delivery
Electrochemical etching of metal wires is widely used to fabricate sharp probes for use in scanning tunnelling microscopy. In this work an electrochemical fabrication method for sharp aluminium probes coated with nanoporous anodised aluminium oxide (AAO) layer is described. The method presented here involves simultaneous anodisation and etching of aluminium wires. The probe apex radius as well as the nanopore length and diameter depend on the etching mode, which could be direct current (DC), alternating current (AC), or pulsed voltage mode (PVM). The probes, coated with a nanoporous AAO layer, were used to demonstrate addressed DNA delivery.
Antibacterial Activity of Extracts from Some Bryophytes
The antimicrobial activity of aqueous and ethanolic extracts of 11 Bryophyta species and 9 Marchantiophyta species collected in Latvia was tested against Staphylococcus aureus, Escherichia coli and Bacillus cereus. The extract of Lophocolea heterophylla inhibited the growth of B. cereus, but none of the tested extracts inhibited the growth of E. coli. 70% of bryophyte species demonstrated certain activity in relation to S. aureus. In general, 73% of ethanolic extracts and 39% of aqueous extracts exhibited antibacterial activity against S. aureus. The highest degree of antibacterial activity against S. aureus was shown by the ethanolic extract of Dicranum scoparium and aqueous extracts of At…
The Influence of the Hot Water Extract from Shiitake Medicinal Mushroom, Lentinus edodes (Higher Basidiomycetes) on the Food Intake, Life Span, and Age-Related Locomotor Activity of Drosophila melanogaster
Shiitake medicinal mushroom, Lentinus edodes, is among the most widely cultivated edible mushrooms in the world and is a well-studied source of nutrients and biologically active compounds. We have studied the influence of the dietary supplement of the polysaccharides containing a hot water extract of the mushroom L. edodes on the fruit fly Drosophila melanogaster in terms of food intake, body weight, life span, and age-related locomotor activity. L. edodes extract, when added to the D. melanogaster feeding substrate at a 0.003-0.030% concentration (calculated for the dry weight of the polysaccharide fraction) did not influence food intake or body weight of the flies. It increased the life s…
Efficient Control of raf Gene Expression by CAP and Two Raf Repressors that Bend DNA in Opposite Directions
The plasmid-borne raf operon of Escherichia coli encodes proteins involved in the uptake and utilisation of the trisaccharide raffinose. The operon is subject to dual regulation; to negative control by the binding of RafR repressor to twin operators, O1 and O2, and to positive control by the cAMP-binding protein, CAP. We have identified the CAP binding site (CBS) as a 22 bp palindromic sequence with incomplete dyad symmetry by deletion analysis, DNasel footprinting and electrophoretic mobility shift assays (EMSA) of CAP-DNA complexes. The CBS is centred 60.5 bp upstream of the transcription start point and partially overlaps O1. In vivo, CAP increases rafA (alpha-galactosidase) gene express…
Role of two operators in regulating the plasmid-borne raf operon of Escherichia coli
The plasmid-borne raf operon encodes functions required for the inducible uptake and utilization of raffinose in Escherichia coli K12. The expression of three structural genes for alpha-galactosidase (rafA), Raf permease (rafB) and sucrose hydrolase (rafD) is negatively controlled by the binding of RafR repressor (rafR) to two operator sites, O1 and O2, that flank the -35 sequence of the raf promoter, PA. In vitro, O1 and O2 are occupied on increasing the concentration of RafR, without detectable preference for one site or the other or any indication of cooperative binding. Nucleotide substitutions at positions 3, 4 or 5 in an operator half-site prevented repressor binding, supporting a mod…
Analysis of Specific Protein-DNA Interactions
The central issue in the regulation of genome functions is the mechanism of sequence-specific protein-nucleic acid interactions. Gene expression, replication, recombination and DNA condensation in chromatin are steered by binding of regulatory protein ligands to specific sites in DNA. Numerous methods have been developed to study protein-DNA interactions. In this chapter we discuss two widely used and straightforward approaches to address this problem.
Treatment of Knee Osteoarthritis with Bone Marrow-Derived Mononuclear Cell Injection: 12-Month Follow-up.
Objectives To evaluate the main symptoms of knee osteoarthritis (OA) and tissue structure changes after a single dose bone marrow–derived mononuclear cell (BM MNC) intra articular injection. Case series study. Patients with knee OA Kellgren Lawrence (K-L) grade II and III received 1 injection of BM MNC. The clinical results were analyzed with the Knee injury and Osteoarthritis Outcome Score (KOOS) and Knee Society Score (KSS) before, 3, 6, and 12 months after injection. Radiological evaluation was performed with a calibrated x-ray and the magnetic resonance (MR) imaging before and 6 to 7 months postinjection. Results A total of 34 knees were treated with BM MNC injections. Mean (±SD) age of…
Primary culture of avian embryonic heart forming region cells to study the regulation of vertebrate early heart morphogenesis by vitamin A
Background: Important knowledge about the role of vitamin A in vertebrate heart development has been obtained using the vitamin A-deficient avian in ovo model which enables the in vivo examination of very early stages of vertebrate heart morphogenesis. These studies have revealed the critical role of the vitamin A-active form, retinoic acid (RA) in the regulation of several developmental genes, including the important growth regulatory factor, transforming growth factor-beta2 (TGFβ2), involved in early events of heart morphogenesis. However, this in ovo model is not readily available for elucidating details of molecular mechanisms determining RA activity, thus limiting further examination o…
Mechanical and electroconductive properties of spatially distributed double stranded DNA arrays on Au (111)
Abstract Conductive AFM was used to investigate electroconductivity through 10 nm long double stranded DNA molecules in mixed monolayers of thioalkylated-DNA and mercaptohexanol (MCH) on Au (111) surface. The distribution of DNA molecules on the surface was analyzed by tapping mode AFM. Measurements performed in lift mode confirmed that the DNA molecules protrude from the surface rather than lie horizontally adsorbed on the interface. The optimal conductivity measurement time, which is shorter than the mechanical relaxation time of oligonucleotide duplexes, was determined. It was concluded that oligonucleotide duplexes have a resistance of the order of ~ 2 Ω ⁎ m at 1 V.
Colloidal nanoparticle sorting and ordering on anodic alumina patterned surfaces using templated capillary force assembly
Abstract A new, robust technique of size-selective nanoparticle ordering on porous anodized aluminum oxide (PAAO) templates is presented. Simultaneous particle sorting and array formation is achieved for the first time using a polydisperse suspension of irregularly shaped diamond nanocrystals. The array parameters can be tuned through a balance of evaporation driven particle flux, capillary, electrostatic, and adhesion forces, which are influenced by the asperities of the surface during the capillary and convective assembly dip-coating process. The resulting structures are dense (lower limit approximately 50 nm center separation), isolated (non-touching) nanoparticle arrays with a size dist…
Epigenetic Status of an Adenovirus Type 12 Transgenome upon Long-Term Cultivation in Hamster Cells
ABSTRACT The epigenetic status of integrated adenovirus type 12 (Ad12) DNA in hamster cells cultivated for about 4 decades has been investigated. Cell line TR12, a fibroblastic revertant of the Ad12-transformed epitheloid hamster cell line T637 with 15 copies of integrated Ad12 DNA, carries one Ad12 DNA copy plus a 3.9-kbp fragment from a second copy. The cellular insertion site for the Ad12 integrate, identical in both cell lines, is a >5.2-kbp inverted DNA repeat. The Ad12 transgenome is packaged around nucleosomes. The cellular junction is more sensitive to micrococcal nuclease at Ad12-occupied sites than at unoccupied sites. Bisulfite sequencing reveals complete de novo methylation i…
Metal hydride alloys for storing hydrogen produced by anaerobic bacterial fermentation
Abstract This study reports on hydrogen sorption from bacterial fermentation media with powdered palladium (Pd) and alloys (LaNi5, AB5, and AB2) that are capable of forming hydrides. Mass changes of the powders after incubation in fermentation media were measured by differential thermogravimetry. Composition and concentrations of the gases accumulated during fermentation and absorbed by Pd or the alloys were analyzed by mass spectrometry. The results demonstrated that hydrogen (H2) was absorbed and stored by powdered Pd and alloys directly from nutritional broth. The best sorption was obtained with Pd, followed by alloys AB5 and AB2. Scanning electron microscopy revealed that bacteria were …