Evaluation of Factors Influencing Outcomes in Pauci-Immune Crescentic Glomerulonephritis: Single Centre Experience of 51 Cases.

INTRODUCTION: Pauci-immune crescentic glomerulonephritis (PICGN) is rare form of glomerulonephritis that frequently presents as rapidly progressive renal failure. Several prior studies have evaluated role of various factors influencing outcomes in patients with PICGN. The histopathological classification proposed by Berden a decade earlier described difference in the outcomes of patients in the focal, crescentic, mixed and sclerotic category with best prognosis for focal and worst for sclerotic group. The newly proposed renal risk score of Brix takes into account both the histopathological parameters (% of normal glomeruli, tubular atrophy and interstitial fibrosis) and clinical parameter (eGFR) which influences outcome. METHODS: Retrospective study was performed between 2014 to 2018. Biochemical parameters and ANCA details were recorded and renal histopathology slides were reviewed and classified according to Berden's histopathologic classes. All the cases were further characterized into three groups based on renal risk score (Brix et al). Univariate, multivariate analysis for risk factors predicting ESRD and Kaplan Meier Survival Analysis were done. RESULTS: In the present study, we found eGFR (P 0.024), % of normal glomeruli (P 0.023) and IFTA (P 0.001) as important factors influencing renal outcome in patients with PICGN. More than 60% patients achieved complete remission with low renal risk score as compared to patients with high renal risk score in which 80% patients developed ESRD or death at follow up. We also found significant difference in survival among various renal risk categories (Log-Rank P = 0.001) as compared to Berden's international histological classification (Log-Rank P = 0.037) on Kaplan -Meier survival analysis. CONCLUSION: PICGN is a significant cause of mortality and morbidity. Renal histological factors such as % normal glomeruli at time of biopsy, degree of IFTA and renal risk score play an important role in assessing prognosis in these patients.

Mapping of yellow mosaic virus (YMV) resistance in soybean (Glycine max L. Merr.) through association mapping approach.

Yellow Mosaic Virus (YMV) is a serious disease of soybean. Resistance to YMV was mapped in 180 soybean genotypes through association mapping approach using 121 simple sequence repeats (SSR) and four resistance gene analogue (RGA)-based markers. The association mapping population (AMP) (96 genotypes) and confirmation population (CP) (84 genotypes) was tested for resistance to YMV at hot-spot consecutively for 3 years (2007-2009). The genotypes exhibited significant variability for YMV resistance (P < 0.01). Molecular genotyping and population structure analysis with 'admixture' co-ancestry model detected seven optimal sub-populations in the AMP. Linkage disequilibrium (LD) between the markers extended up to 35 and 10 cM with r2 > 0.15, and >0.25, respectively. The 4 RGA-based markers showed no association with YMV resistance. Two SSR markers, Satt301 and GMHSP179 on chromosome 17 were found to be in significant LD with YMV resistance. Contingency Chi-square test confirmed the association (P < 0.01) and the utility of the markers was validated in the CP. It would pave the way for marker assisted selection for YMV resistance in soybean. This is the first report of its kind in soybean.

Sample size for collecting germplasms--a polyploid model with mixed mating system.

The present paper discusses a general expression for determining the minimum sample size (plants) for a given number of seeds or vice versa for capturing multiple allelic diversity. The model considers sampling from a large 2 k-ploid population under a broad range of mating systems. Numerous expressions/results developed for germplasm collection/regeneration for diploid populations by earlier workers can be directly deduced from our general expression by assigning appropriate values of the corresponding parameters. A seed factor which influences the plant sample size has also been isolated to aid the collectors in selecting the appropriate combination of number of plants and seeds per plant. When genotypic multiplicity of seeds is taken into consideration, a sample size of even less than 172 plants can conserve diversity of 20 alleles from 50,000 polymorphic loci with a very large probability of conservation (0.9999) in most of the cases.