BIOLOGICAL SCIENCES (DANISH-I ZISTI-I IRAN)
Year:2008 | Volume:3 | Issue:2|Papers Count:7

Trichophyton rubrum is one of the anthropophagic dermatophytes with worldwide distribution. This fungus is a common causative agent of tinea cruris, tinea corporis, tinea manuum and tinea pedis. Current laboratory methods are main methods to study this fungus, even though taking a long time. In spite of many studies in the field of cellular and molecular biology, molecular investigations on dermatophyte fungi are very few and limited. Nowadays resistance had been seen against antifungal drugs. Producing of new drugs or accession to suitable efficacy of existing drugs require more study and finding in the field of molecular biology. In this fundamental study, serial dilutions of griseofulvin with fungal growth were prepared and compared with control sample that was not affected by any drugs. RNAs were then extracted. Afterwards Multiplex-PCR was performed simultaneously for chitin synthase and mg/ml beta actin genes in each one of three samples.Microscopically, rate of shortened and twisted mycelia in 0.02 dilution of griseofulvin was much higher than in 0.006 mg/ml dilutions. But regarding the gene expression of chitin synthesis, there was no difference between the control sample and ones affected by griseofulvin.

In order to study the effect of Azotobacter chroococcum and Bradyrhizobium japonicum on soybean [Glycine max (L.) Merr] cultivar seed characteristics produced under water stress, a factorial test was conducted in form of completely randomized design with four replications. Treatments were water stress [Irrigation after 50 mm (normal irrigation), 100 mm (mild stress), and 150 mm (severe stress) evaporation from pan of class A], Cultivar [Manokin, SRF×T3, Williams] and inoculation [Bradyrhizobium japonicum, Bradyrhizobium japonicum co-inoculated with Azotobacter chroococcum, control]. The result showed that stress has significant effect on time, speed and percent of germination. Seedling inoculated with Bradyrhizobium japonicum, had higher length compared to seeding not inoculated. The dry weight of Seedling grown from seeds produced under mild stress was 10% higher the one that in normal irrigation. Bradyrhizobium japonicum, co-inoculated with Azotobacter chroococcum, increased mean time of germination and root dry weight. Seeds produced under mild stress as compared to normal irrigation, had further seedling and stem length. Therefore, bacteria couldn’t compensate severe stress effects and just increased seed characteristics of mild stress condition.

In order to have adaptation and tolerance for the environmental stresses, different plant species show different physiological responses. In this study, the effect of water stress on biomass, change in content of soluble sugars, proline, K+, Na+ and activity of peroxidase and catalase was investigated in one sunflower (Helianthus annuus L.) cultivar including of Record. An experiment was carried out under potting conditions and 5 treatments (10, 20, 30, 40 and 50% of water saturation capacity) and 4 replicates of CRD was used. Total dry weight, total leaf chlorophyl, total soluble sugars and proline, Na+, K+ in leaf and enzymes activity of catalase and peroxidase in leaf were measured. Results showed that total chlorophyll and K+ in leaf significantly decreased in comparison to control sample (50% of water saturation capacity) by increasing water stress. Dry weight decreased with increasing water stress and significantly decreased in treatments of 10 and 20% of water saturation capacity in comparison to control sample. Na+ in leaf significantly increased with increasing of water stress. Total soluble sugars and proline increased by increasing water stress. Enzyme activity of catalase in leaf increased with increasing water stress and significantly increased in treatments of 10 and 20% of water saturation capacity in comparison to control sample. Also in the leaf, peroxidase activity significantly increased in treatments of 10, 20 and 30% in comparison to control sample. Sugars and proline accumulation probably play an important role in osmoregulation and tolerance to water stress conditions. In addition, the increase of enzymes activity in leaf is necessary for protecting against oxidative damages and defense against the water stress.

Three iso-alkyldithiocarbonates (xanthates), as sodium salts, C3H7OCS2Na (I), C4H9OCS2Na (II) and C5H11OCS2Na (III) were synthesized, by the reaction between CS2 and the corresponding iso-alcohol in the presence of NaOH. These compounds were examined for inhibition of cresolase activity of mushroom tyrosinase (MT) from a commercial source of Agricus bisporus.4- [(4-methylphenyl) azo] -phenol (MePAPh) were used as synthetic substrate for the enzyme for the cresolase reaction. Lineweaver-Burk plots showed different patterns of mixed and competitive inhibition for the three xanthates. For cresolase activity, I and II showed a mixed inhibition pattern but III showed a competitive inhibition pattern. These new synthesized compounds are potent inhibitors of MT with Ki values of 9.8, 7.2 and 6.1 microM for cresolase inhibitory activity, for compound-I, -compound-II and compound-III, respectively. Both substrate and inhibitor can be bound to the enzyme with negative cooperativity between the binding sites (a>1) and this negative cooperativity increases with increasing length of the aliphatic tail in these compounds in cresolase activity. The cresolase inhibition is related to the chelating of the copper ions at the active site by a negative head group (S-) of the anion xanthate, which leads to similar values of Ki for all three xanthates.

The purpose of present study is, a randomized trial to compare the effects of aerobic and resistance regimens on coronary risk factors in young and athlete men, fifty-one sedentary students as volunteers were randomized to three groups with mean±SD of age, height and weight included endurance (n=17, 21±17years, 1.76±0.1cm, 69.3±6.19kg), resistance (n=18, 22±2.23years, 1.72±0.12cm, 70.10±6.94kg) and control (c=16, 22±3.4 years, 1.74±0.08cm, 73.6±4.88kg). Endurance training program include running at 60-70% HRR for 30-45 min, 3days/ wk and resistance training program including perform 3set, 3 days /wk, 10-12 repetition, with 60-90 second for recovery, using seven exercises for 12 weeks. The results of two way analysis of variance showed that: Both experimental groups have a significant increase in maximal oxygen consumption, and the endurance training group also showed a reduction in BMI and body fat percentage, p<0.05. In Endurance group TG (8%), TC (7%), and LDL-C (14%) and in resistance group TG (11%), TC (71%) and LDL-C (12%) decrease significantly. The HDL-C levels also significantly increase in endurance (5%) and resistance (9%) training groups (p<0.05).

Salinity in soil or water is of importance for agriculture because it limits a distribution of higher plants in certain natural habitats and induces a wide range of adverse metabolic response in them. The influence of arbuscular mycorrhizal (AM) fungus Glomus etunicatum on characteristics of growth, antioxidant enzymes, such as catalase (CAT), peroxidase (PX), flavonoids, cartenoides and chlorophyll content of Pistacia vera under salt stress was studied in the greenhouse. Pistachio plants were grown in sterilzed, sand and soil mixture with G.etunicatum inoculum with four NaCl levels (0, 50, 100, and 200 mM) for 90 days. Root length colonized percent was higher in control plant than treated plants with different salt concentration. Under salt stress, mycorrhizal pistachio plants had higher growth, higher antioxidant enzymes activity, higher flavonoids, and chlorophyll content, compared with non-mycorrhizal plants. All of the results show that G.etunicatum alleviates the deleterious effect of salt stress on plant growth through improving pigments content and antioxidant defense systems.

Chronic Myeloid Leukemia (CML) is produced by the chromosomal translocation and fusion of bcr/abl genes. The purpose of this study was the development of a simple and low-cost technique for quantitative detection of bcr/abl transcripts in CML patients. This study, we used the competitive RT-PCR technique to determine the number of bcr/abl transcripts. The internal control was designed from a non-human DNA source with the same flanking sequences but a smaller size than the target segment. After amplification and purification of internal control DNA, PCR products were quantified based on copy numbers. In order to optimize the reaction condition, competitive RT-PCRs were carried out separately on target and internal control DNAs each with specific copy numbers, and final products of all concentrations were run on agarose gel electrophoresis.The simultaneous reactions of target RNA with different copy numbers of internal control DNA showed that the copy numbers of target RNA can be determined by comparison of dye density emission of DNA bands (target and control DNA) on the gel. This study shows that competitive RT-PCR is a partially efficient and cheap method for quantitative determination of bcr/abl transcripts, compared to other methods such as Real-time PCR.