International Chronic Ocular Graft-vs-Host-Disease (GVHD) Consensus Group: Proposed Diagnostic Criteria for Chronic GVHD (Part I)

The International Chronic Ocular GVHD Consensus Group held 4 working meetings to define new diagnostic metrics for chronic ocular graft-versus-host disease (GVHD). After considering the factors currently used to diagnose chronic ocular GVHD, the Consensus Group identified 4 subjective and objective variables to measure in patients following allogeneic hematopoietic stem cell transplantation (HSCT): OSDI, Schirmer's score without anesthesia, corneal staining, and conjunctival injection. Each variable was scored 0–2 or 0–3, with a maximum composite score of 11. Consideration was also given to the presence or the absence of systemic GVHD. On the basis of their composite score and the presence or absence of systemic GVHD, patients were assigned to one of three diagnostic categories: NO, PROBABLE, or DEFINITE ocular GVHD. New diagnostic criteria for chronic ocular GVHD are presented by the Consensus Group. Validation studies are needed to identify the best combination of the proposed metrics to maximize diagnostic sensitivity and specificity

Application of option valuation techniques in valuing petroleum leases

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1994.GRSN 681684Includes bibliographical references (leaves 141-143).by Sohel K. Shikari.M.S

Comparison of selection indices for screening maize (Zea mays L.) germplasm for cold tolerance

The comparisons among the 6 selection indices S 1 , S 2 , S 3 (simultaneous selection indices comprising of X 1 only; X 1 +X 5 and X 1 +X 2 +X 3 +X 4 respectively as their component traits), S 4 (Rank summation index), S 5 (Baker’s standard deviation index) and S 6 (Elston’s weight free index) were made involving 4 primary cold tolerance traits namely field emergence per cent (X 1 ), fresh seedling root mass (X 2 ), seedling dry weight (X 3 ), days to 50% silk emergence (X 5 ) along with grain yield ha −1 (X 4 ). Highly significant rank correlations of proposed selection indices conferred the suitability in use of one index if substituted for other, to score the genotypes for selection. Selection differentials for all the indices were generally positive with respect to the traits X 1 , X 2 , X 3 and X 4 except S 2 which, was accompanied with negative differentials for X 2 , X 3 and X 4 . S 1 was found to be an important cold tolerance trait depicting not so less differentials compared to other traits and had positive differentials under each selection criteria. Index S 6 was efficient in selecting early silking varieties with high yield and tolerance to cold. The populations NDSM 8 WN, NDSAB (MER), NDSLC and land races GL20W and Dawar-2 showed high degree of cold tolerance among 67 genotypes evaluated and showed at par results with the C 15 check which was top ranking under 5 out of 6 selection used

Improved protocol for efficacious in vitro androgenesis and development of doubled haploids in temperate japonica rice.

DH (Doubled haploid) is the immortal mapping population and an outcome of single meiotic cycle, contributed from male partner. An improved procedure was developed for high frequency androgenesis in japonica genotypes, K-332 and GS-88 and their F1s. A total of 207 fertile, green, di-haploid plants were generated from K-332 × GS-88 hybrids using the improved anther culture protocol. The investigation was carried out to evaluate callus induction potential and regeneration response for the genotypes and the derived F1s on N6 media and modified N6 media (N6M). Whereas, N6 failed to induce callusing, agarose solidified N6M media supplemented with 4% maltose, growth regulators; NAA (2 mg/l), 2, 4-D (0.5 mg/l), Kinetin (0.5 mg/l), and silver nitrate induced high calli percentage of 27.6% in F1s, 9.5% and 6.7% in GS-88 and K-332 respectively. Murashige and Skoog (MS) media supplemented with 3% sucrose, and the hormonal combination BAP (2 mg/l), Kinetin (1 mg/l) and NAA (1 mg/l) induced high green shoot regeneration rates (0-60.0%). The effect of cold pre-treatment at 4°C and the stage of anther collection and their interaction was studied. The effect of cold pre-treatment (CP) of collected boots at 4°C (for CP2: 2, CP4: 4, CP6: 6 and CP8: 8 days) at different stages of panicle emergence (BES4-6: 4-6, BES7-10: 7-10, BES11-13: 11-13, BES>13: more than 13 inches was worked out in relation to the effect on response of calli induction, albino regeneration, green plant regeneration and number of shoots/green calli. CP referred to the number of days for which the collected boots were incubated before they were inoculated. BES was the length (inches) between flag leaf and penultimate leaf at the time of boot collection. We concluded that CP6 and BES7-10 showed better response to callus proliferation and regeneration of plantlets across genotypes. The appropriate pre-treatment, stage of anther collection and favourable media composition resulted in high calli induction and green plant regeneration rates in recalcitrant japonica genotypes. The modified N6 media resulted into efficient callus induction and is expected to be useful for studies which aim at rapid generation of mapping populations for genetic studies

Advances and opportunities in unraveling cold-tolerance mechanisms in the world’s primary staple food crops

Temperatures below or above optimal growth conditions are among the major stressors affecting productivity, end-use quality, and distribution of key staple crops including rice (Oryza sativa), wheat (Triticum aestivum), and maize (Zea mays L.). Among temperature stresses, cold stress induces cellular changes that cause oxidative stress and slowdown metabolism, limit growth, and ultimately reduce crop productivity. Perception of cold stress by plant cells leads to the activation of cold-responsive transcription factors and downstream genes, which ultimately impart cold tolerance. The response triggered in crops to cold stress includes gene expression/suppression, the accumulation of sugars upon chilling, and signaling molecules, among others. Much of the information on the effects of cold stress on perception, signal transduction, gene expression, and plant metabolism are available in the model plant Arabidopsis but somewhat lacking in major crops. Hence, a complete understanding of the molecular mechanisms by which staple crops respond to cold stress remain largely unknown. Here, we make an effort to elaborate on the molecular mechanisms employed in response to low-temperature stress. We summarize the effects of cold stress on the growth and development of these crops, the mechanism of cold perception, and the role of various sensors and transducers in cold signaling. We discuss the progress in cold tolerance research at the genome, transcriptome, proteome, and metabolome levels and highlight how these findings provide opportunities for designing cold-tolerant crops for the future

Do diverse wheat genotypes unleash their biochemical arsenal differentially to conquer cold stress? A comprehensive study in the Western Himalayas

Wheat is one of the most important cereal crops in the world. Cold stress is a major constraint in production of wheat grown in cold climate regions. In this study, we conducted a comprehensive assessment of cold stress tolerance in wheat genotypes through field screening, cell membrane stability through electrolyte leakage assay and biochemical profiling. A core set comprising 4560 genotypes was evaluated for two years (2021–2022), revealing substantial genetic variation for cold stress tolerance. Most genotypes exhibited moderate tolerance, while a smaller proportion showed susceptibility to cold stress. Based on the cold screening data in the field, a mini-core set of 350 genotypes was selected for membrane stability analysis using electrical conductivity assays. Significant differences were observed in membrane stability among the genotypes, indicating the presence of genetic variation for this trait. Furthermore, a mini-core set was narrowed down to 50 diverse candidate genotypes that were subsequently profiled for various biochemicals, including reactive oxygen species (ROS) like lipid peroxidation (MDA) and hydrogen peroxide (H202), osmoprotectant (proline) and enzymatic antioxidants including ascorbate peroxidase (APX), superoxide dismutase (SOD), guaiacol peroxidase (GPX), and catalase (CAT). Correlation analysis of the biochemicals revealed negative associations between antioxidants and reactive oxygen species (ROS), highlighting their role in mitigating oxidative damage under cold stress. This study enhances our understanding of the physiological and biochemical mechanisms underlying cold stress tolerance in wheat. The identified genotypes with superior cold stress tolerance can serve as valuable genetic resources for wheat breeding