OGG1 DNA Repair Gene Polymorphism As a Biomarker of Oxidative and Genotoxic DNA Damage

Background:Single nucleotide polymorphisms in OGG1 gene modulates DNA repair capacity and functions as one of the first lines of protective mechanisms against 8-OHdG mutagenicity. OGG1-Cys326 gene polymorphism may decrease DNA repair function, causing oxidative stress due to higher oxidative DNA damage. The main purpose of this study was to examine the link of oxidative and genotoxic DNA damage with DNA repair OGG1 gene polymorphism, in charcoal workers exposed to polyaromatic hydrocarbons. Methods:Urinary 8-OHdG excretion (a biomarker of oxidative DNA damage) was determined in both exposed and control populations. Genotyping of OGG1 DNA repair gene in the blood samples of subjects was carried out by PCR-RFLP method. Results:The 8-OHdG urinary concentration was significantly higher (p < 0.05) in the exposed (geometric mean 12.33 ± 3.78) than in the unexposed (geometric mean 7.36 ± 2.29) population. DNA damage, as measured by 8-OHdG and TM content, was found to be significantly higher in OGG1 homozygous mutants (mt/mt; 18.81 ± 3.34; 6.04 ± 0.52) as compared to wild-type genotypes (wt/wt; 10.34 ± 2.25; 5.19 ± 2.50) and heterozygous (wt/mt) mutants (12.82 ± 2.81; 6.04 ± 0.93) in the exposed group. Conclusion:We found a significant association of OGG1 heterozygous (wt/mt) and homozygous (mt/mt) variants with oxidative and genotoxic damage, suggesting that these polymorphisms may modulate the effects of PAH exposure in occupational workers. Key Words: 8-hydroxy-2’-deoxyguanosine, 1-hydroxypyrene, Polycyclic aromatic hydrocarbons     

Trends of climatic potential and on-farm yields of rice and wheat in the Indo-Gangetic Plains

Rice and wheat are the two most important cereals in the Indo-Gangetic Plains (IGP) and are responsible for the food security of the region. To understand the productivity trends in the transects of the IGP: (1) the climatic potential yields of rice and wheat were simulated using a crop simulation modeling approach and (2) the long-term trends of potential and on-farm yields were compared. The potential yields of rice and wheat in the IGP ranged from 7.7 to 10.7 and 5.2 to 7.9 Mg ha⁻¹, respectively. The upper transects of the IGP are more productive and yield decreases by 27% for rice and by 32% for wheat from transect 2 to transect 5. The rate of change in the potential yield trend of rice from 1985 to 2000 ranged from −0.12 to 0.05 Mg ha⁻¹ per year. Negative yield trends were observed at six of the nine sites, four of which were statistically significant (P<0.05). The decrease in radiation and increase in minimum temperature were the reasons for the yield decline. The potential yield trend of wheat, however, appeared to be stable. On-farm yields of rice also showed a negative trend but for wheat the trend was mostly positive. The adverse changes in the weather parameters and declining trends of potential and on-farm yields of rice should be taken as an indication of a future problem. Regular on-farm monitoring of crops and climatic factors is urgently needed for predicting problems and allowing measures to be taken to improve productivity.     

AM fungi ameliorates growth, yield and nutrient uptake in Cicer arietinum L. Under salt stress

A pot experiment was performed to see the effect of two indigenous arbuscular mycorrhizal (AM) fungi Glomus mosseae and Acaulospora laevis, alone and in combination on growth, biomass and mineral nutrition of Cicer arietinum under different salinity levels imposed by 4, 8, and 12 dS/m EC solution (sodium chloride, calcium chloride and sodium sulphate). All AM inoculated plants showed significant increment in growth, biomass, mineral nutrition and yield over control. The extent of bioinoculants response on plant growth as well as root colonization decreases with the increase in the level of salinity. Among all the growth parameters plant height (26.4 ± 1.14 cm), root length (13.4 ± 1.67 cm), total chlorophyll (2.33 ± 0.02 mg/100 mg f. wt), root colonization (41.6 ± 2.70%) and AM spore number (63.8 ± 1.78 per 10 gm soil) were recorded highest in dual combination (G. mosseae and A. laevis) at 4 dS/m while fresh shoot (6.80 ± 0.67 gm) and dry shoot weight (0.96 ± 0.18 gm) was found maximum in G. mosseae at the same concentration of salinity. Greater Phosphorus (P) acquisition and yield was observed at 4 dS/m with dual combination (G. mosseae and A. laevis) that possibly be responsible to protect plants from salt stress. Although Nitrogen (N), Potassium (K) and Sodium (Na) contents also declined with increasing salinity. Overall results showed that mycorrhizal colonization improves host plant mineral concentration and thereby increases the growth, yield and nutrient uptake of C. arietinum ameliorating the harmful effect at salinity stress.     

Longitudinal growth strains in five clones of Eucalyptus tereticornis Sm.

We studied the variability in longitudinal growth strains and wood basic density in five-year old trees from five clones (one tree per clone) of Eucalyptus tereticornis. Mean longitudinal growth strain in clones ranged from 466 to 876 μm. There was a significant difference between clones in growth strains and wood basic density. Clone 10 exhibited maximum growth strains and basic density, whereas clone 3 and clone 7 exhibited minimum growth strains and basic density, respectively. Within a tree, the growth strain variation with tree height was high but statistically insignificant while within tree variation in basic density was very small. There was no specific trend in variation in either strain or density within a tree. There was 5% 200% difference in growth strain on opposite sides of the logs. However two strains showed a strong positive correlation. There was a moderate positive association of wood basic density and mean growth strains in logs. The variation around the periphery emphasize the need to measure strain more than one, preferably on opposite sides at the same height, on a tree to know the mean strain level for the purpose of selection of clones.     

Evaluation of mulberry germplasm for resistance to powdery mildew in the field and greenhouse

Powdery mildew caused by the ascomycete Phyllactinia guttata (syn. P. corylea) is a major foliar disease worldwide of the unique mulberry (Morus spp.) for silkworm feed. Genetic resistance to powdery mildew, the most sustainable and economical strategy for disease control, is still elusive for tropical mulberry. About 147 germplasm sources, representing 18 countries of origin, were screened for resistance to P. guttata in six seasonal fields and greenhouse trials after exposure to natural and artificial inoculum, respectively. In the field, the level of plant responsiveness to disease was assessed from 30 to 62 days after pruning in each season as variations in the disease severity index (DSI), disease incidence (DI%) and area under the disease progress curve (AUDPC). These measures differed significantly among the germplasm. Of 147 germplasm sources, ~6.8% had useful resistance (two high and nine moderately resistant) to the powdery mildew pathogen on the basis of DSI. The AUDPC values were 13.5-fold higher in the most susceptible accession—(Philippines) than the least responsive (Vietnam-2). The results of DSI were strongly correlated with the obtained DI values (r = 0.92; P < 0.01) and AUDPC (r = 0.89; P < 0.01). Moreover, field screening results were highly correlated (R ² = 0.839) with values from the greenhouse evaluation using artificial inoculum. However, the DSI values in field and greenhouse screenings for three sources (Non-nayapati, Nao-khurkul and Tista Valley) varied significantly. A relatively low disease reaction of 09 resources (Vietnam-2, Ankara and 07 others) using different assessment scales after natural and artificial inoculation prove, for the first time, that they have potential in breeding for resistance in tropical mulberry to powdery mildew.     

Sequence and topological characterization of Toll-like receptor 8 gene of Indian riverine buffalo (Bubalus bubalis)

In this study, buffalo (Bubalus bubalis) Toll-like receptor 8 (TLR8) gene has been characterized by sequence analysis and detecting polymorphism. Complete ORF of buffalo TLR8 gene was amplified using the RNA isolated from spleen tissue, which was found to be 3,102 nucleotides long encoding a 1,033 amino acid protein. Buffalo TLR8 had 10 nucleotide changes as compared to other livestock species resulting in six unique amino acid changes, four of them lying within leucine-rich repeat (LRR) domains. As compared to cattle (Bos indicus and Bos taurus), out of fifteen cysteine residues, fourteen were conserved and Cys at position 521 was replaced by Arg. Nine of the LRR domains had no amino acid change as compared to cattle, whereas LRR-C-terminus had maximum, five amino acid changes. Sequence characterization of 12 riverine and swamp buffaloes revealed presence of four polymorphic nucleotides, two of them were non-synonymous, one synonymous and one site in 3′UTR. PCR-RFLP genotyping of non-synonymous SNP 2758A>G (ILeu920Val) in Toll–interleukin-1 receptor domain of 463 swamp and riverine buffaloes showed a higher frequency of allele A in swamp (95 %) as compared to riverine (9.84 %) buffaloes.     

Heat shock protein 70, oxidative stress, and antioxidant status in periparturient crossbred cows supplemented with α-tocopherol acetate

The study was conducted to investigating the effect of α-tocopherol acetate on heat shock protein 70 (Hsp70), oxidative stress, and antioxidant status during periparturient period in medium body condition score crossbred cows. Twenty crossbred Karan Fries cows with confirmed pregnancy were selected 2 months before expected date of calving. The cows were randomly distributed in to two groups: 10 cows were kept as control and 10 were supplemented with α-tocopherol acetate during dry period for 2 months. Blood samples were collected at ?20, ?10, ?5, 0, 5, 10, and 20 days in relation to the expected date of calving. Superoxide dismutase, catalase, and total immunoglobulin were significantly higher (P?<?0.01) in treatment as compared to control cows. Heat shock protein 70 and thiobarbituric acid reactive substance levels were significantly lower (P?<?0.01) in the treatment cows than their counterpart. Treatment with α-tocopherol acetate during dry period resulted in reduced oxidative stress, heat shock protein Hsp70 levels, improved antioxidant, and improved immunity status indicating beneficial effect of α-tocopherol acetate treatment.     

Inactivation of Macrophomina phaseolina Propagules during Composting and Effect of Composts on Dry Root Rot Severity and on Seed Yield of Clusterbean

Survival of a heat-tolerant pathogen Macrophomina phaseolina, causing dry root rot of clusterbean, was studied by incorporation and retrieval of infected residue samples at various stages of the composting process of pearl millet (Pennisetum glaucum) and clusterbean (Cyamopsis tetragonoloba) residues. During the heating phase, temperatures varied from 48–51°C at 30cm and 60–62°C at 60cm depth in compost pits. Reduction in survival of M. phaseolina propagules (13–23%) was significantly higher in the residues enriched with 4% urea-N and kept at 60cm compared to 2% urea-N and at 30cm. However, a heat phase (48–62°C) was not enough to completely eradicate M. phaseolina propagules from infected residues. Further reductions (54–61%) in survived propagules were achieved by sub-lethal temperatures (48–53°C) when moistened compost materials were exposed to heat during summer days. Beneficial effects of composts were ascertained on dry root rot intensity, seed yield of clusterbean and densities of M. phaseolina, Nitrosomonas and antagonists in soil. In a two-year field study, all the composts significantly reduced plant mortality due to dry root rot and increased the yield of clusterbean. The highest disease suppression and yield promotion were recorded in soil amended with pearl millet compost and cauliflower leaf residue compost, respectively. Soil amendment with compost also lead to a significant reduced density of M. phaseolina and an increased density of antagonistic actinomycetes, lytic bacteria and Nitrosomonas. Among composts, greater potential of cauliflower compost in enhancing population of antagonists in soil was discernible.     

Insecticide Resistance Management of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) and its effect on pests and yield of cotton in North India

Journal of Plant Diseases and Protection - An insecticide resistance management (IRM) strategy was devised and evaluated for the management of cotton bollworm, Helicoverpa armigera (Lep.,...     

Production and characterisation of two monoclonal antibodies recognising equine IgG Fc receptors

Despite the importance of IgG Fc receptors in the regulation of various immunological mechanisms, these receptors have not been well characterised in the domesticated animals including equines. This paper describes the production of two monoclonal antibodies (CVS 59 and CVS 61) that recognise equine IgG Fc receptors. Fusions were conducted using BALB/c mice hyperimmunised with equine peripheral blood mononuclear cells. Hybridoma supernatants were screened on the basis of their ability to inhibit the rosetting of equine antibody coated sheep erythrocytes with equine peripheral blood mononuclear cells. The mAbs were then characterised for cellular distribution of the antigen by flow cytometry. Using immunoprecipitation, it was shown that both under reducing and non-reducing conditions, CVS 59 and CVS 61 precipitated a 80 and 40 kD protein, respectively. From the functional study coupled with cellular distribution and molecular weight of the antigen recognised by these mAbs, it would appear that CVS 59 and CVS 61 recognise an epitope on equine equivalent of human and murine FcgammaRIII and FcgammaRII, respectively.