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111.
Kiran Nawaz Ahmad Ali Shahid Louis Bengyella Muhammad Nasir Subhani Muhammad Ali Waheed Anwar Sehrish Iftikhar Shinawar Waseem Ali 《World journal of microbiology & biotechnology》2018,34(9):130
Chili pepper (Capsicum annum L.) is an important economic crop that is severely destroyed by the filamentous oomycete Phytophthora capsici. Little is known about this pathogen in key chili pepper farms in Punjab province, Pakistan. We investigated the genetic diversity of P. capsici strains using standard taxonomic and molecular tools, and characterized their colony growth patterns as well as their disease severity on chili pepper plants under the greenhouse conditions. Phylogenetic analysis based on ribosomal DNA (rDNA), β-tubulin and translation elongation factor 1α loci revealed divergent evolution in the population structure of P. capsici isolates. The mean oospore diameter of mating type A1 isolates was greater than that of mating type A2 isolates. We provide first evidence of an uneven distribution of highly virulent mating type A1 and A2 of P. capsici that are insensitive to mefenoxam, pyrimorph, dimethomorph, and azoxystrobin fungicides, and represent a risk factor that could ease outpacing the current P. capsici management strategies. 相似文献
112.
Sujay S. Kaushal Arthur J. Gold Susana Bernal Tammy A. Newcomer Johnson Kelly Addy Amy Burgin Douglas A. Burns Ashley A. Coble Eran Hood YueHan Lu Paul Mayer Elizabeth C. Minor Andrew W. Schroth Philippe Vidon Henry Wilson Marguerite A. Xenopoulos Thomas Doody Joseph G. Galella Phillip Goodling Katherine Haviland Shahan Haq Barret Wessel Kelsey L. Wood Norbert Jaworski Kenneth T. Belt 《Biogeochemistry》2018,141(3):281-305
In the Anthropocene, watershed chemical transport is increasingly dominated by novel combinations of elements, which are hydrologically linked together as ‘chemical cocktails.’ Chemical cocktails are novel because human activities greatly enhance elemental concentrations and their probability for biogeochemical interactions and shared transport along hydrologic flowpaths. A new chemical cocktail approach advances our ability to: trace contaminant mixtures in watersheds, develop chemical proxies with high-resolution sensor data, and manage multiple water quality problems. We explore the following questions: (1) Can we classify elemental transport in watersheds as chemical cocktails using a new approach? (2) What is the role of climate and land use in enhancing the formation and transport of chemical cocktails in watersheds? To address these questions, we first analyze trends in concentrations of carbon, nutrients, metals, and salts in fresh waters over 100 years. Next, we explore how climate and land use enhance the probability of formation of chemical cocktails of carbon, nutrients, metals, and salts. Ultimately, we classify transport of chemical cocktails based on solubility, mobility, reactivity, and dominant phases: (1) sieved chemical cocktails (e.g., particulate forms of nutrients, metals and organic matter); (2) filtered chemical cocktails (e.g., dissolved organic matter and associated metal complexes); (3) chromatographic chemical cocktails (e.g., ions eluted from soil exchange sites); and (4) reactive chemical cocktails (e.g., limiting nutrients and redox sensitive elements). Typically, contaminants are regulated and managed one element at a time, even though combinations of elements interact to influence many water quality problems such as toxicity to life, eutrophication, infrastructure corrosion, and water treatment. A chemical cocktail approach significantly expands evaluations of water quality signatures and impacts beyond single elements to mixtures. High-frequency sensor data (pH, specific conductance, turbidity, etc.) can serve as proxies for chemical cocktails and improve real-time analyses of water quality violations, identify regulatory needs, and track water quality recovery following storms and extreme climate events. Ultimately, a watershed chemical cocktail approach is necessary for effectively co-managing groups of contaminants and provides a more holistic approach for studying, monitoring, and managing water quality in the Anthropocene. 相似文献
113.
Ehsan Ullah Mughal Asif Javid Amina Sadiq Shahzad Murtaza Muhammad Naveed Zafar Bilal Ahmad Khan Sajjad Hussain Sumrra Muhammad Nawaz Tahir Khalid Mohammed Khan 《Bioorganic & medicinal chemistry》2018,26(12):3696-3706
The prime objective of this research work is to prepare readily soluble synthetic analogues of naturally occurring 3-O-flavonol glycosides and then investigate the influence of various substituents on biological properties of synthetic compounds. In this context, a series of varyingly substituted 3-O-flavonol glycosides have been designed, synthesized and characterized efficiently. The structures of synthetic molecules were unambiguously corroborated by IR, 1H, 13C NMR and ESI-MS spectroscopic techniques. The structure of compound 22 was also analyzed by X-ray diffraction analysis. All the synthetic compounds (21–30) were evaluated for in vitro inhibitory potential against cholinesterase enzymes. The results displayed that most of the derivatives were potent inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with varying degree of IC50 values. The experimental results were further encouraged by molecular docking studies in order to explore their binding behavior with the active pocket of AChE and BChE enzymes. The experimental and theoretical results are in parallel with one another. 相似文献
114.
M. M. Ali P. Krishnamurthy M. H. El-Hadary J. M. Kim M. A. Nawaz S. H. Yang G. Chung 《Russian Journal of Plant Physiology》2016,63(3):383-390
Cyclization of 2,3-oxidosqualene by different oxidosqualene cyclase (OSC) genes is responsible for sapogenin heterogeneity. The very first phase is the conversion of 2,3-oxidosqualene into β-amyrin by β-amyrin synthase (BAS) gene, a member of OSC family, in soy saponin biosynthesis pathway. This paper reports the identification of a new BAS gene (GmBAS3) and its expression pattern in soybean (Glycine max (L.) Merr.). GmBAS3 gene was identified by PCR/RACE method with an open reading frame of 2286 bp nucleotides encoding a 762 amino acid long protein devouring a characteristic QW motif repeated five times and DCTAE motif. GmBAS3 shared 96 and 92% homology with Glycyrrhiza uralensis BAS and Lotus japonicus putative BAS respectively. Expression of the gene was detected by RT-PCR in regard to seedlings age and tissue type. A spatio-temporal expression of GmBAS3 was found in 21-day-old seedlings in the hypocotyls, young leaves and mature leaves but not observed in stem and root tissues. No expression was perceived in 10-day-old seedling. This study also support the premise that β-amyrin synthesis hang on more than one type of BAS genes with there expression in different plant parts at different times. 相似文献
115.
116.
Improving magnesium uptake,photosynthesis and antioxidant enzyme activities of watermelon by grafting onto pumpkin rootstock under low magnesium 总被引:1,自引:0,他引:1
Yuan Huang Yanyan Jiao Muhammad Azher Nawaz Chen Chen Li Liu Zhen Lu Qiusheng Kong Fei Cheng Zhilong Bie 《Plant and Soil》2016,398(1-2):229-241
Background and aims
Magnesium (Mg) is an essential macronutrient that plays an important role in numerous physiological and biochemical processes of plant. However, Mg deficiency commonly occurs worldwide. Watermelon is an important crop that often suffers from Mg deficiency. This study aims to test whether watermelon performance can be improved by grafting onto rootstocks under low Mg and to clarify the underlying physiological mechanism.Methods
Self-grafted, bottle gourd (Jingxinzhen No.1) and pumpkin (Jingxinzhen No.4) rootstock-grafted plants were treated with three Mg concentrations: 2.0 mM (normal condition), 0.4 mM (moderate stress), and 0.04 mM (severe stress) for 16 days under hydroponic conditions. Ungrafted watermelon and pumpkin were treated with 2.0 mM and 0.04 mM for 12 days.Results
The growth of the plants was not affected by 0.4 mM Mg; however, plant growth decreased under 0.04 mM Mg in all graft combinations compared with control (2.0 mM Mg). Pumpkin rootstock grafting significantly increased watermelon growth under low Mg stress (0.04 mM Mg), compared with self-grafted and bottle gourd-grafted plants. The Mg2+ uptake of watermelon plants was increased by grafting onto pumpkin rootstocks, however, root-to-shoot transport capacity of Mg2+ was similar compared with self-grafted plants under 0.04 mM Mg. Gene expression analysis showed that magnesium transporter genes MGT1, MGT3, MGT4, and MGT5 may play an important role in higher Mg2+ uptake of pumpkin root. The photosynthetic parameters and activities of superoxide dismutase, peroxidase and catalase were significantly higher, but malonaldehyde (MDA) content were lower in the pumpkin rootstock grafted plants compared with other graft combinations under 0.04 mM Mg.Conclusion
Our results provide strong evidence that pumpkin rootstock ‘Jinxinzhen No. 4’ grafting can improve watermelon performance under low Mg stress. The enhanced plant performance is attributed to higher root Mg2+ uptake and the improvement of photosynthesis and antioxidant enzyme activities.117.
Md. Shariful Alam Jilani Jamshedul Alam Mohammad Robayet Md. Mohiuddin Md. Rokib Hasan Chowdhury Rafiqul Ahsan Jalaluddin Ashraful Haq 《PLoS neglected tropical diseases》2016,10(1)
Background
Melioidosis, caused by Burkholderia pseudomallei, is an endemic disease in Bangladesh. No systematic study has yet been done to detect the environmental source of the organism and its true extent in Bangladesh. The present study attempted to isolate B. pseudomallei in soil samples and to determine its seroprevalence in several districts in Bangladesh.Methodology and Results
Soil samples were collected from rural areas of four districts of Bangladesh from where culture confirmed melioidosis cases were detected earlier. Multiple soil samples, collected from 5–7 sampling points of 3–5 sites of each district, were cultured in Ashdown selective media. Suspected colonies of B. pseudomallei were identified by biochemical and serological test, and by polymerase chain reaction (PCR) using 16s rRNA specific primers. Blood samples were collected from 940 healthy individuals of four districts to determine anti- B. pseudomallei IgG antibody levels by indirect enzyme linked immunosorbent assay (ELISA) using sonicated crude antigen. Out of 179 soil samples, B. pseudomallei was isolated from two samples of Gazipur district which is located 58 km north of capital Dhaka city. Both the isolates were phenotypically identical, arabinose negative and showed specific 550bp band in PCR. Out of 940 blood samples, anti- B. pseudomallei IgG antibody, higher than the cut-off value (>0.8), was detected in 21.5% individuals. Seropositivity rate was 22.6%-30.8% in three districts from where melioidosis cases were detected earlier, compared to 9.8% in a district where no melioidosis case was either detected or reported (p<0.01). Seropositivity increased with the advancement of age from 5.3% to 30.4% among individuals aged 1–10 years and > 50 years respectively. The seropositivity rates were 26.0% and 20.6% in male and female respectively, while it was 20–27% among different occupational groups. No significant association was observed with gender (χ2 = 3.441, p = 0.064) or any occupational group (χ2 = 3.835, p = 0.280).Conclusion
This is the first study demonstrating the presence of B. pseudomallei in the environmental (soil) samples of Bangladesh. It also suggested that a large proportion of people, residing in these districts, were exposed to the organism. 相似文献118.
The distribution between carnitine and the acyl derivatives of carnitine reflects changes in the metabolic state of a variety of tissues. Patients with peripheral vascular disease (PVD) develop skeletal muscle ischemia with exertion. This impairment in oxidative metabolism during exercise may result in the generation of acylcarnitines. To test this hypothesis, 11 patients with PVD and 7 age-matched control subjects were evaluated with graded treadmill exercise. Subjects with PVD walked to maximal claudication pain at a peak O2 consumption (VO2) of 19.9 +/- 1.3 ml X kg-1 X min-1 (mean +/- SE). Control subjects were taken to a near-maximal work load at a VO2 of 31.3 +/- 1.0 ml X kg-1 X min-1. In patients with PVD, the plasma concentration of total acid-soluble, long-chain acylcarnitine and total carnitine was increased at peak exercise compared with resting values. Four minutes postexercise, the plasma short-chain acylcarnitine concentration was also increased. In control subjects taken to the higher work load, only the long-chain acylcarnitine concentration was increased at peak exercise. In patients with PVD, plasma short-chain acylcarnitine concentration at rest was negatively correlated with subsequent maximal walking time (r = -0.51, P less than 0.05). In conclusion, acylcarnitines increased in patients with PVD who walked to maximal claudication pain, whereas control subjects did not show equivalent changes even when taken to a higher work load. The relationship between short-chain acylcarnitine concentration at rest and subsequent exercise performance suggests that repeated episodes of ischemia may cause chronic accumulation of short-chain acylcarnitine in plasma in proportion to the severity of disease.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
119.
Ahmad Ajmal Nawaz Mohd Imtiaz Siddiquei Mohammad Mairaj Abu El-Asrar Ahmed M. 《Molecular and cellular biochemistry》2021,476(5):2099-2109
Molecular and Cellular Biochemistry - NADPH oxidase (NOX) is a main producers of reactive oxygen species (ROS) that may contribute to the early pathogenesis of diabetic retinopathy (DR). ROS has... 相似文献
120.