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11.
Chromium and its compounds may cause disturbance in the nutrient level of the plants. Iron, manganese, copper, and zinc are
essential nutrient elements and required for balanced growth and development of plants, but chromium uptake sometimes disturbed
their concentration in plants. Therefore, in the present paper, an effort has been made to observe the effect of different
levels of Cr on nutrient uptake of Phyllanthus amarus and Solanum nigrum, the medicinally important plants of indigenous systems of medicine having hepatoprotective and diuretic properties. The
study revealed that Cr causes significant changes in nutrient uptake as compared to control plants. Besides, Cr-treated plants
showed growth depression and decrease in fresh and dry weight too. With the increase in Cr supply, accumulation of Cr in roots
was increased significantly. Concentration of manganese and zinc was also increased. However, copper concentration in both
the plants seemed less affected by Cr. 相似文献
12.
Impact of hypoglycemia and diabetes on CNS: correlation of mitochondrial oxidative stress with DNA damage 总被引:3,自引:0,他引:3
Oxidative stress plays an important role in tissue damage caused by hypoglycemia and diabetes, which may be the result of deterioration in glucose homeostasis caused by these metabolic disorders. The present study examined the effects of insulin-induced hypoglycemia and streptozotocin induced diabetes on mitochondrial lipid peroxidation and antioxidant enzymes from different brain regions, namely, cerebral hemispheres, cerebellum, brain stem and diencephalon. In situ localization of DNA single strand breaks (SSBs) were also studied by DNA polymerase-I mediated biotin dATP labeled nick translation method after inducing hypoglycemia and diabetes. Significant decrease in mitochondrial catalase, manganese superoxide-dismutase (Mn-SOD) and reduced glutathione (GSH) content and increase in the lipid peroxidation (LPx) and glutathione peroxidase (GPx) activity was observed under these metabolic stress conditions with more pronounced effects in hypoglycemic group. We conclude that during severe energy deprivation following hypoglycemia and diabetes, mitochondrial free radicals scavenger system is down regulated, which leads to reactive oxygen species (ROS) generation. High levels of ROS in turn activate the processes leading to DNA damage. DNA SSBs, which indicates nuclear disintegration is an important feature of neuronal cell death. 相似文献
13.
A new species, Goffartia phalacra n. sp. is described and illustrated. The body is thin and slender with L = 511 to 646 μm; a = 37.1 to 47.4; b = 4.8 to 6; c = 2.6 to 4.8; c′ = 13.6 to 32.8; V = 40% to 49% in females. Males are smaller but similar to females and the posterior region is strongly curved. The species is characterized by a tubular stoma, a smooth round lip region, anterior pharynx much smaller than posterior pharynx, two pairs of unicellular glands associated with the vagina, and males with a broad keel-shaped gubernaculum. G. phalacra n. sp. can be differentiated from all other species of the genus by its lip region and the structure of the gubernaculum. This is the first instance of a species of Goffartia occurring in a terrestrial habitat and the first report of a species from India. 相似文献
14.
Sharma Himanshu Kumar Pankaj Singh Abhishek Aggarwal Kanika Roy Joy Sharma Vikas Rawat Sandeep 《Molecular biology reports》2020,47(4):2447-2457
Molecular Biology Reports - The genus Rhododendron, known for large impressive flowers is widely distributed throughout the world. Rhododendrons have limited genetic information, despite of... 相似文献
15.
Over two billion people, depending largely on staple foods, suffer from deficiencies in protein and some micronutrients such as iron and zinc. Among various approaches to overcome protein and micronutrient deficiencies, biofortification through a combination of conventional and molecular breeding methods is the most feasible, cheapest, and sustainable approach. An interspecific cross was made between the wheat cultivar 'Chinese Spring' and Aegilops kotschyi Boiss. accession 396, which has a threefold higher grain iron and zinc concentrations and about 33% higher protein concentration than wheat cultivars. Recurrent backcrossing and selection for the micronutrient content was performed at each generation. Thirteen derivatives with high grain iron and zinc concentrations and contents, ash and ash micronutrients, and protein were analyzed for alien introgression. Morphological markers, high molecular weight glutenin subunit profiles, anchored wheat microsatellite markers, and GISH showed that addition and substitution of homoeologous groups 1, 2, and 7 chromosomes of Ae. kotschyi possess gene(s) for high grain micronutrients. The addition of 1U/1S had high molecular weight glutenin subunits with higher molecular weight than those of wheat, and the addition of 2S in most of the derivatives also enhanced grain protein content by over 20%. Low grain protein content in a derivative with a 2S-wheat translocation, waxy leaves, and absence of the gdm148 marker strongly suggests that the gene for higher grain protein content on chromosome 2S is orthologous to the grain protein QTL on the short arm of group 2 chromosomes. 相似文献
16.
17.
Sharma RK Tuli P Makkar SS 《Plastic and reconstructive surgery》2007,119(7):2330; author reply 2330-2330; author reply 2331
18.
Background
The development in the deinking process has made recycled fiber a major part of the raw material for pulp and paper industry. Enzymes have revolutionized the deinking process obtaining brightness levels surpassing conventional deinking processes. This study explores the deinking efficiencies of bacterial alkalophilic laccase (L) and xylanase (X) enzymes along with physical deinking methods of microwaving (MW) and sonication (S) for recycling of old newsprint (ONP).Methods and Results
The operational parameters viz. enzyme dose, pH and treatment time for X and L deinking were optimized statistically using Response Surface Methodology. Laccase did not require any mediator supplementation for deinking. Deinking of ONP pulp with a combination of xylanase and laccase enzymes was investigated, and fiber surface composition and morphological changes were studied using X-ray diffraction, fourier transform infrared spectroscopy and scanning electron microscopy. Compared to the pulp deinked with xylanase (47.9%) or laccase (62.2%) individually, the percentage reduction of effective residual ink concentration (ERIC) was higher for the combined xylanase/laccase-deinked pulp (65.8%). An increase in brightness (21.6%), breaking length (16.5%), burst factor (4.2%) tear factor (6.9%), viscosity (13%) and cellulose crystallinity (10.3%) along with decrease in kappa number (22%) and chemical consumption (50%) were also observed. Surface appeared more fibrillar along with changes in surface functional groups. A combination of physical and enzymatic processes (S-MW-XL) for deinking further improved brightness (28.8%) and decreased ERIC (73.9%) substantially.Conclusion
This is the first report on deinking of ONP with laccase without any mediator supplementation. XL pretreatment resulted in marked improvement in paper quality and a new sequence being reported for deinking (S-MW-XL) will contribute further in decreasing chemical consumption and making the process commercially feasible. 相似文献19.
Michela Menegon Azucena Bardají Flor Martínez-Espinosa Camila B?tto-Menezes Maria Ome-Kaius Ivo Mueller Inoni Betuela Myriam Arévalo-Herrera Swati Kochar Sanjay K. Kochar Puneet Jaju Dhiraj Hans Chetan Chitnis Norma Padilla María Eugenia Castellanos Lucía Ortiz Sergi Sanz Mireia Piqueras Meghna Desai Alfredo Mayor Hernando del Portillo Clara Menéndez Carlo Severini 《PloS one》2016,11(3)
Plasmodium vivax is the most widely distributed human parasite and the main cause of human malaria outside the African continent. However, the knowledge about the genetic variability of P. vivax is limited when compared to the information available for P. falciparum. We present the results of a study aimed at characterizing the genetic structure of P. vivax populations obtained from pregnant women from different malaria endemic settings. Between June 2008 and October 2011 nearly 2000 pregnant women were recruited during routine antenatal care at each site and followed up until delivery. A capillary blood sample from the study participants was collected for genotyping at different time points. Seven P. vivax microsatellite markers were used for genotypic characterization on a total of 229 P. vivax isolates obtained from Brazil, Colombia, India and Papua New Guinea. In each population, the number of alleles per locus, the expected heterozygosity and the levels of multilocus linkage disequilibrium were assessed. The extent of genetic differentiation among populations was also estimated. Six microsatellite loci on 137 P. falciparum isolates from three countries were screened for comparison. The mean value of expected heterozygosity per country ranged from 0.839 to 0.874 for P. vivax and from 0.578 to 0.758 for P. falciparum. P. vivax populations were more diverse than those of P. falciparum. In some of the studied countries, the diversity of P. vivax population was very high compared to the respective level of endemicity. The level of inter-population differentiation was moderate to high in all P. vivax and P. falciparum populations studied. 相似文献
20.
Xenorhabdus nematophila produces type 1 fimbriae on the surface of Phase I cells. Fimbriae mediate recognition and adhesion of the bacteria to its target cell. To investigate the role of fimbriae in the biology of X. nematophila , we have produced a fimbrial mutant strain by insertional inactivation of the mrx A gene, encoding the structural subunit of type 1 fimbriae. Phenotypic characterization of the mutant revealed loss of fimbriae on the cell surface. Cell surface characteristics like dye absorption, biofilm formation, red blood cell agglutination remained unaltered. The mrx A mutant was defective in swarming on soft agar, although swimming motility was not affected. Flagellar expression was suppressed in the mrxA strain under swarming conditions, but not swimming conditions. Agglutination and cytotoxicity of the mutant to larval haemocytes was also reduced. When the mutant cells were injected in the haemocoel of the fourth instar larvae of Helicoverpa armigera , an increase in the LT50 of 9–12 h was observed relative to the wild-type strain. The nematode growth was slow on the lawn of the fimbrial mutant. The mrxA negative strain was unable to colonize the nematode gut efficiently. This study demonstrates importance of type 1 fimbriae in establishment of bacteria-nematode symbiosis, a key to successful pest management program. 相似文献