Seed priming with selenium improves the maize performance

Sardar Alam Cheema,Asmat Ulllah,Muhammad Farooq 단국대학교 국제농업협력연구소 2012 단국대학교 국제농업협력연구소 학술대회 Vol.2012 No.1

A field experiment was conducted to study the effect of selenium priming on growth and productivity of maize at Agronomy Research Area, University of Agriculture, Faisalabad. Maize seeds were primed with different concentrations of selenium (0, 5, 25, 50 and 100 JlM) while untreated seeds were taken as control. Results showed that seed priming with all levels of selenium improved the germination parameters, growth and yield of maize. Seed priming with 50 JlM of selenium recorded maximum grain yield (2.35 t ha- 1) while minimum (1.66 t ha-1) grain yield was observed in case of untreated seeds (control). Further research should be carried out to find out mechanisms of growth and yield improvement of maize as a result of seed priming with selenium.

Biotoxicity assessment of pyrene in soil using a battery of biological assays.

Khan, Muhammad Imran,Cheema, Sardar Alam,Tang, Xianjin,Shen, Chaofeng,Sahi, Shahbaz Talib,Jabbar, Abdul,Park, Joonhong,Chen, Yingxu Springer-Verlag 2012 Archives of environmental contamination and toxico Vol.63 No.4

<P>A test battery, composed of a range of biological assays, was applied to evaluate the ecological health of soil aged for 69 days and spiked with a range of pyrene levels (1.04, 8.99, 41.5, 72.6, 136, and 399 μg g(-1) dry soil; Soxhlet-extracted concentrations after 69 days of aging). Chinese cabbage (Brassica rapa), earthworm (Eisenia fetida), and bacteria (Vibrio fischeri) were used as test organisms to represent different trophic levels. Among the acute ecotoxicity bioassays used, the V. fischeri luminescence inhibition assay was the most sensitive indicator of pyrene toxicity. We observed >8 % light inhibition at the lowest concentration (1.04 μg g(-1)) pyrene, and this inhibition increased to 60 % at 72.6 μg g(-1). The sensitivity ranking for toxicity of the pyrene-contaminated soil in the present study was in the following decreasing order: root elongation of Chinese cabbage < earthworm mortality (14 days) < earthworm mortality (28 days) < luminescence inhibition (15 min) < luminescence inhibition (5 min). In addition, genotoxic effects of pyrene were also evaluated by using comet assay in E. fetida. The strong relationship between DNA damage and soil pyrene levels showed that comet assay is suitable for testing the genotoxicity of pyrene-polluted soil. In addition, tail moment was well correlated with soil pyrene levels (r (2) = 0.99). Thus, tail moment may be the most informative DNA-damage parameter representing the results of comet assay. Based on these results, the earthworm DNA damage assay and Microtox test are rapid and sensitive bioassays and can be used to assess the risk of soil with low to high levels of hydrocarbon pollution. Furthermore, an analysis of the toxic effects at several trophic levels is essential for a more comprehensive understanding of the damage caused by highly contaminated soil.</P>

Assessment of phenanthrene bioavailability in aged and unaged soils by mild extraction.

Khan, Muhammad Imran,Cheema, Sardar Alam,Shen, Chaofeng,Zhang, Congkai,Tang, Xianjin,Shi, Jiyan,Chen, Xincai,Park, Joonhong,Chen, Yingxu D. Reidel Pub. Co ; Springer 2012 Environmental monitoring and assessment Vol.184 No.1

<P>It has become apparent that the threat of an organic pollutant in soil is directly related to its bioavailable fraction and that the use of total contaminant concentrations as a measure of potential contaminant exposure to plants or soil organisms is inappropriate. In light of this, non-exhaustive extraction techniques are being investigated to assess their appropriateness in determining bioavailability. To find a suitable and rapid extraction method to predict phenanthrene bioavailability, multiple extraction techniques (i.e., mild hydroxypropyl-β-cyclodextrin (HPCD) and organic solvents extraction) were investigated in soil spiked to a range of phenanthrene levels (i.e., 1.12, 8.52, 73, 136, and 335?μg?g(?-?1) dry soil). The bioaccumulation of phenanthrene in earthworm (Eisenia fetida) was used as the reference system for bioavailability. Correlation results for phenanthrene suggested that mild HPCD extraction was a better method to predict bioavailability of phenanthrene in soil compared with organic solvents extraction. Aged (i.e., 150?days) and fresh (i.e., 0?day) soil samples were used to evaluate the extraction efficiency and the effect of soil contact time on the availability of phenanthrene. The percentage of phenanthrene accumulated by earthworms and percent recoveries by mild extractants changed significantly with aging time. Thus, aging significantly reduced the earthworm uptake and chemical extractability of phenanthrene. In general, among organic extractants, methanol showed recoveries comparable to those of mild HPCD for both aged and unaged soil matrices. Hence, this extractant can be suitable after HPCD to evaluate risk of contaminated soils.</P>

A Sporolactobacillus-, Clostridium-, and Paenibacillus- Dominant Microbial Consortium Improved Anaerobic RDX Detoxification by Starch Addition

Muhammad Imran Khan,유근제,김성훈,Sardar Alam Cheema,Safdar Bashir,박준홍 한국미생물·생명공학회 2020 Journal of microbiology and biotechnology Vol.30 No.6

In the present study, an anaerobic microbial consortium for the degradation of hexahydro-1,3,5- trinitro-1,3,5-triazine (RDX) was selectively enriched with the co-addition of RDX and starch under nitrogen-deficient conditions. Microbial growth and anaerobic RDX biodegradation were effectively enhanced by the co-addition of RDX and starch, which resulted in increased RDX biotransformation to nitroso derivatives at a greater specific degradation rate than those for previously reported anaerobic RDX-degrading bacteria (isolates). The accumulation of the most toxic RDX degradation intermediate (MNX [hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine]) was significantly reduced by starch addition, suggesting improved RDX detoxification by the co-addition of RDX and starch. The subsequent MiSeq sequencing that targeted the bacterial 16S rRNA gene revealed that the Sporolactobacillus, Clostridium, and Paenibacillus populations were involved in the enhanced anaerobic RDX degradation. These results suggest that these three bacterial populations are important for anaerobic RDX degradation and detoxification. The findings from this work imply that the Sporolactobacillus, Clostridium, and Paenibacillus dominant microbial consortium may be valuable for the development of bioremediation resources for RDX-contaminated environments.

Loss of LKB1 Protein Expression Correlates with Increased Risk of Recurrence and Death in Patients with Resected, Stage II or III Colon Cancer

Maria Sfakianaki,Chara Papadaki,Maria Tzardi,Maria Trypaki,Sardar Alam,Eleni D. Lagoudaki,Ippokratis Messaritakis,Odysseas Zoras,Dimitris Mavroudis,Vassilis Georgoulias,John Souglakos 대한암학회 2019 Cancer Research and Treatment Vol.51 No.4

Purpose The purpose of this study was to investigate the prognostic significance of liver kinase b1 (LKB1) loss in patients with operable colon cancer (CC). Materials and Methods Two hundred sixty-two specimens from consecutive patients with stage III or high-risk stage II CC, who underwent surgical resection with curative intent and received adjuvant chemotherapy with fluoropyrimidine and oxaliplatin, were analyzed for LKB1 protein expression loss, by immunohistochemistry as well as for KRAS exon 2 and BRAFV600E mutations by Sanger sequencing and TS, ERCC1, MYC, and NEDD9 mRNA expression by real-time quantitative reverse transcription polymerase chain reaction. Results LKB1 expression loss was observed in 117 patients (44.7%) and correlated with right-sided located primaries (p=0.032), and pericolic lymph nodes involvement (p=0.003), BRAFV600E mutations (p=0.024), and TS mRNA expression (p=0.041). Patients with LKB1 expression loss experienced significantly lower disease-free survival (DFS) (hazard ratio [HR], 1.287; 95% confidence interval [CI], 1.093 to 1.654; p=0.021) and overall survival (OS) (HR, 1.541; 95% CI, 1.197 to 1.932; p=0.002), compared to patients with LKB1 expressing tumors. Multivariate analysis revealed LKB1 expression loss as independent prognostic factor for both decreased DFS (HR, 1.217; 95% CI, 1.074 to 1.812; p=0.034) and decreased OS (HR, 1.467; 95% CI, 1.226 to 2.122; p=0.019). Conclusion Loss of tumoral LKB1 protein expression, constitutes an adverse prognostic factor in patients with operable CC.