High pressure effects on cellular expression profile and mRNA stability. A cDNA array analysis

Hydrostatic pressure has a profound effect on cartilage tissue and chondrocyte metabolism. Depending on the type and magnitude of pressure various responses can occur in the cells. The mechanisms of mechanotransduction at cellular level and the events leading to specific changes in gene expression are still poorly understood. We have previously shown that induction of stress response in immortalized chondrocytes exposed to high static hydrostatic pressure increases the stability of heat shock protein 70 mRNA. In this study, our aim was to examine the effect of high pressure on gene expression profile and to study whether stabilization of mRNA molecules is a general phenomenon under this condition. For this purpose a cDNA array analysis was used to compare mRNA expression profile in pressurized vs. non-pressurized human chondrosarcoma cells (HCS 2/8). mRNA stability was analyzed using actinomycin-treated and nontreated samples collected after pressure treatment. A number of immediate-early genes, and genes regulating cell cycle and growth were up-regulated due to high pressure. Decrease in osteonectin, fibronectin, and collagen types VI and XVI mRNAs was observed. Also bikunin, cdc37 homologue and Tiam1, genes linked with hyaluronan metabolism, were down-regulated. In general, stability of down-regulated mRNA species appeared to increase. However, no increase in mRNA above control level due to stabilization was noticed in the genes available in the array. On the other hand, mRNAs of certain immediate-early genes, like c-jun, jun-B and c-myc, became destabilized under pressure treatment. Increased accumulation of mRNA on account of stabilization under high pressure conditions seems to be a tightly regulated, specific phenomenon.     

Immunocytolocalization of tryptophan decarboxylase in Catharanthus roseus hairy roots

We investigated the intracellular distribution of tryptophan decarboxylase (TDC) (EC 4.1.1.28) in Catharanthus roseus hairy roots using immunofluorescence and immunogold techniques. TDC was detected by immunofluorescence localization in the cytosol and in the apoplastic region of the meristematic cells of the roots, with a slight enrichment in the epidermal cells of the root cap and in the meristematic region. In the enlargement zone, TDC was localized only in the first three layers of the cortex. In the maturation zone, the enzyme was not present. Immunogold studies confirmed that the enzyme was localized in the cytosol of the meristematic region, and intense gold labeling was found in the apoplastic zone. A protein fraction isolated from the apoplastic zone and assayed for TDC activity showed high activity.     

Humus bacteria of Norway spruce stands: plant growth promoting properties and birch, red fescue and alder colonizing capacity

We studied the potential of the humus layer of the Norway spruce stands to supply beneficial rhizobacteria to birch (Betula pendula), alder (Alnus incana) and fescue grass (Festuca rubra), representatives of pioneer vegetation after clear-cutting of the coniferous forest. Axenically grown seedlings of these species were inoculated with the acid spruce humus, pH 3.7-5.3. Actinorhizal propagules, capable of nodulating alder, were present in high density (10(3) g(-1)) in humus of long-term limed plots, whereas plots with nitrogen fertilization contained almost none (相似文献   

Effects of anti-TNF therapy on glucose metabolism in patients with ankylosing spondylitis,psoriatic arthritis or juvenile idiopathic arthritis

The objective of this study was to evaluate the influence of anti-tumor necrosis factor (anti-TNF) in juvenile idiopathic arthritis (JIA), ankylosing spondylitis (AS) or psoriatic arthritis (PsA). Sixty-two patients were investigated: 7 JIA; 37 AS; and 18 PsA. Caucasian race accounted for 79% and 29% were female. Mean age was 40.4 ± 12.6years. None of the patients had a history of diabetes, and none had used oral hypoglycemic agents or insulin. Treatment was with adalimumab, infliximab and etanercept. Glucose, inflammatory markers and prednisone dose were assessed at baseline, as well as after three and six months of treatment. The mean erythrocyte sedimentation rate was significantly lower at three months and six months than at baseline (13.7 ± 18.0 and 18 ± 22.5 vs. 27.9 ± 23.4 mm; p = 0.001). At baseline, three months and six months, we found the following: mean C-reactive protein levels were comparable (22.1 ± 22.7, 14.5 ± 30.7 and 16.0 ± 23.8 mg/L, respectively; p = 0.26); mean glucose levels remained unchanged (90.8 ± 22.2 mg/dl, 89.5 ± 14.6 mg/dl and 89.8 ± 13.6 mg/dl, respectively; p = 0.91); and mean prednisone doses were low and stable (3.9 ± 4.9 mg/day, 3.7 ± 4.8 mg/day and 2.6 ± 4.0 mg/day, respectively; p = 0.23). During the first six months of treatment, anti-TNF therapy does not seem to influence glucose metabolism in JIA, AS or PsA.     

BpMADS4 has a central role in inflorescence initiation in silver birch (Betula pendula)

Acceleration of flowering would be beneficial for breeding trees with a long juvenile phase; conversely, inhibition of flowering would prevent the spread of transgenes from the genetically modified trees. We have previously isolated and characterized several MADS genes from silver birch ( Betula pendula Roth). In this study, we investigated the more detailed function of one of them, BpMADS4 , a member of the APETALA1/FRUITFULL group of MADS genes. The expression of BpMADS4 starts at very early stage of the male and female inflorescence development and the activity is high in the apex of the developing inflorescence. Later, some expression is detected in the bracts and in the flower initials. Ectopic expression of BpMADS4 accelerates flowering dramatically in normally flowering clones and also in the early-flowering birch clone, in which the earliest line flowered about 11 days after rooting, when the saplings were only 3 cm high. The birches transformed with the BpMADS4 antisense construct showed remarkable delay in flowering and the number of flowering individuals was reduced. Two of the transformed lines did not show any signs of flower development during our 2-year study, whereas all the control plants formed inflorescences within 107 days. Our results show that BpMADS4 has a critical role in the initiation of birch inflorescence development and that BpMADS4 seems to be involved in the transition from vegetative to reproductive development. Therefore, BpMADS4 provides a promising tool for the genetic enhancement of forest trees.     

Antimicrobial activity of two antitumour agents and ribonucleotide reductase inhibitors, pyridine-2-carboxaldehyde thiosemicarbazone and the acetate form of its copper(II) chelate

Some copper chelates have potent antitumour activity, and in some cases also the free ligands have activity in vivo. Yet, little is known about their antimicrobial properties. Copper(II) chelates of the thiosemicarbazones of a-N-heterocyclic carboxaldehydes constitute one important group of such agents, also their ligands having marked antitumour activity. Both the ligands and chelates inhibit ribonucleotide reductase. Some ligands have been or are under clinical trials as antineoplastic agents. I report here a study on the antimicrobial properties of the prototype compounds of this group, pyridine-2-carboxaldehyde thiosemicarbazone and its copper(II) chelate. They were tested against nine microbes, including bacteria (Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis and Streptococcus lactis), yeasts (Candida albicans and Saccharomyces cerevisiae) and one mold (Aspergillus niger). Two clinical isolates of Bacillus sp. and one reference strain were also studied. Both the ligand and the chelate had marked activity. The ligand displayed considerable activity against all bacteria except for S. lactis, and its activity against E. coli and P. aeruginosa was that high that practical applications might be considued. It was highly active against A. niger and moderately active against C. albicans. The chelate was highly active against S. epidermidis and S. cerevisiae. Both compounds inhibited the clinical isolates markedly. Since some related ligands have been or are in clinical trials on humans or are entering them, their route to clinical use, also as antimicrobials, might be much more straightforward than that of substances, whose toxicity in humans is wholly unexplored.     

Antimicrobial properties of substituted salicylaldehydes and related compounds

A systematic survey of the antimicrobial properties of substituted salicylaldehydes and some related aromatic aldehydes is reported. A total of 23 different compounds, each at four different concentrations, were studied using a panel of seven microbes (Aspergillus niger, Bacillus cereus, Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Saccharomyces cerevisiae and Staphylococcus epidermidis) and employing the paper disc agar diffusion method. Several aldehydes, most notably halogenated, nitro-substituted and hydroxylated salicylaldehydes, displayed highly potent activity against the microbes studied, giving inhibitory zones up to 49 mm in diameter (paper disc diameter 6 mm), while unsubstituted benzaldehyde and salicylaldehyde had minimal activity. Further, 4,6-dimethoxysalicylaldehyde had considerable activity against C albicans and slight activity against S. cerevisiae, while displaying minimal activity against bacteria. Also two aromatic dialdehydes had interesting activity. In general, P. aeruginosa was the least sensitive microbe, a result that is in line with observations from a large screening project, in which this microbe was the one against which the least number of active substances was found. Interestingly, the structure-activity relationships of the aldehydes studied were clearly different for different microbes. Many of the aldehydes tested had such high antimicrobial activity that they are noteworthy candidates for practical applications as well as interesting lead compounds for the development of novel antimicrobial drugs and disinfectants. The structure-activity relationships are discussed in detail. For high activity, substituents are required in benzaldehyde as well as in its 2-hydroxy derivative salicylaldehyde. One hydroxy group alone (at the 2-position) is not enough, but further hydroxylation may produce high activity. The effects of substituents are in some cases dramatic. Halogenation, hydroxylation and nitro substitution may produce highly active compounds, but the effects are not easily predicted nor can they be extrapolated from one microbe to another.     

Substituted salicylaldehydes as potential antimicrobial drugs: minimal inhibitory and microbicidal concentrations

Substituted salicylaldehydes are potent antibacterial and antifungal agents and may have chemotherapeutic potential. In the clinical setting, the minimal inhibitory concentration (MIC) as well as the minimal bactericidal and fungicidal concentrations (MBC and MFC, respectively) are of fundamental interest. Therefore, we have now, using a panel of five microbial species (Bacillus cereus, Candida albicans, Escherichia coli, Saccharomyces cerevisiae, and Staphylococcus aureus), determined the MIC and MBC/MFC values of a total of 22 aromatic aldehydes, including 19 substituted salicylaldehydes and the unsubstituted parent compounds benzaldehyde and salicylaldehyde (2-hydroxybenzaldehyde). The results clearly indicate that both of the yeasts studied are remarkably sensitive to various salicylaldehydes and, especially, to halogenated ones. Some congeners clearly merit consideration as potential therapeutic agents for Candida infections. The MIC values of the most potent congeners are of roughly the same magnitude as that of amphotericin B, and the results of the MFC measurements indicate that the compounds are fungicidal. All of the bacteria studied are also sensitive to at least some of the compounds tested but, clearly, this class of antimicrobials has superior activity against yeasts. Structure-activity relationships are discussed for each microbial species and compared with each other. The comparison of the results of MIC and MBC/MFC measurements with those of agar diffusion tests revealed aspects that are of interest concerning the methodology of antimicrobial activity screening. Unexpectedly, it was found that some compounds that are completely devoid of activity in agar diffusion tests had potent activity in MIC tests, indicating that if only agar diffusion methodology is used in drug discovery, some highly active compounds may be missed.