Identification of BLB resistant genes in some rice varieties for development of high yielding bacterial leaf blight tolerant types

Aim: To identify bacterial leaf blight resistant genes in some rice varieties so that these resistant varieties can be used as a good source of donor for BLB resistant genes in genetic enhancement program.Methodology: A total of sixty-one rice genotypes including resistant and susceptible checks were screened in field condition by artificial inoculation using IX020 strain of Xoo for two years (Kharif 2016 and 2017). These varieties were also genotyped for seven SSR markers tagged with major BLB resistant genes, i.e., Xa4, xa5, xa13 and Xa7. Results: In artificial screening, significant disease development was recorded and the varieties were categorized using disease scoring scale of IRRI, 1996 where seven cultivars exhibited resistance, while twenty-seven were found to be moderately resistant. In genotyping, there was distinct difference in banding position for resistant and susceptible genotypes. Genotypes having resistant disease reaction, carrying BLB resistant genes were identified. Interpretation: Genotypes IR-64, IR-68144-2b-2-2-3-1-127, Ratna, Surjamukhi, Kalinga-2, Azucena and Zheshan-2 expressed bands of RM markers closely linked to Xa4, xa5, xa13 and Xa7 BLB resistant genes and field testing also confirmed resistant host reaction against pathogens.

Stapled Haemorrhoidopexy Compared with Conventional Haemorrhoidectomy--A Systematic Review.

Haemorrhoids are one of the most common anorectal disorders. Conventional haemorrhoidectomy (CH) is the most commonly practiced surgical technique. Stapled haemorrhoidopexy (SH) [procedure for prolapsed haemorrhoids (PPH)] is newly developed method for the surgical management of Haemorrhoids. This review looks at the surgical management of prolapsed haemorrhoids in light of this recent development and suggests a treatment approach based on this current evidence. A Medline, Pubmed and Cochrane data base search was performed using key words "haemorrhoid" or 'hemorrhoid' and staple. Relevant papers e.g. randomized controlled trials, review and metaanalyses from different parts of the world were collected. Data were analyzed and compiled. Though early small RCTs (stapled haemorrhoidopexy comparing with traditional excisional surgery) have shown stapled haemorrhoidopexy is less painful and it is associated with quicker recovery but recent large meta-analyses and long term follow up have shown SH is associated with a higher long term risk of haemorrhoid recurrence and symptoms of prolapse.

Left handed DNA in synthetic and topologically constrained form V DNA and its implications in protein recognition.

We have investigated structural transitions in Poly(dG-dC) and Poly(dG-Me5dC) in order to understand the exact role of cations in stabilizing left-handed helical structures in specific sequences andthe biological role, if any, of these structures. From a novel temperature dependent transition it has been shown that a minor fluctuation in Na+ concentration at ambient temperature can bring about Β to Ζ transition. Forthe first time, wehave observed a novel double transition in poly(dG-Me5dC) as the Na+ concentration is gradually increased. This suggests that a minor fluctuation in Na+ concentration in conjunction with methylation may transform small stretches of CG sequences from one conformational state to another. These stretches could probably serve as sites for regulation. Supercoiled formV DNA reconstituted from pBR322 and pßG plasmids have been studied as model systems, in order to understand the nature and role of left-handed helical conformation in natural sequences. A large portion of DNA in form V, obtained by reannealing the two complementary singlestranded circles is forced to adopt left-handed double helical structure due to topological constraints (Lk = 0). Binding studies with Z-DNA specific antibody and spectroscopic studies confirm the presence of left-handed Z-structure in the pßG and pßR322 form V DNA. Cobalt hexamine chloride, which induces Z-form in Poly(dG-dC) stabilizes the Z-conformation in form V DNA even in the non-alternating purine-pyrimidine sequences. A reverse effect is observed with ethidium bromide. Interestingly, both topoisomerase I and II (from wheat germ) act effectively on form V DNA to give rise to a species having an electrophoretic mobility on agarose gel similar to that of open circular (form II) DNA. Whether this molecule is formed as a result of the left-handed helical segments of form V DNA undergoing a transition to the right-handed B-form during the topoisomerase action remains to be solved.