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A comparative bioaccumulation pattern and ultra structural changes were studied in Phragmites cummunis, Typha angustifolia and Cyperus esculentus in mixed metals solution of cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn). P. cummunis was observed to be a shoot accumulator for Cr, Fe, Mn, Ni, Pb, and Zn. However, T. angustifolia was found to be a root accumulator for Cd, Cr, Cu, Fe, Ni and Pb. In addition, C. esculentus also accumulated most of the tested heavy metals in the roots, while Mn and Fe were translocated up to leaves. Further, the long term metal treatment showed maximum accumulation of all heavy metals in P. cummunis followed by T. angustifolia and C. esculentus. Among heavy metals, Fe was accumulated maximum, i.e., >1000 microg g(-1) by all three plants. Simultaneously, the adverse effects on biochemical parameters were noted earlier in C. esculentus than T. angustifolia and P. cummunis. Ultra structural observation showed the cellular changes in wetland plants after longer exposure. Results revealed that P. cummunis and T. angustifolia had more potential for tested metals than C. esculentus. This study established that these wetland plants could be used for heavy metals phytoremediation from metal containing industrial wastewater. 相似文献
33.
Sarkar AK Ghosh D Das A Selvan PS Gowda KV Mandal U Bose A Agarwal S Bhaumik U Pal TK 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,873(1):77-85
A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method was developed and validated for quantification of metoprolol succinate (MPS) and amlodipine besylate (AM) using hydrochlorothiazide (HCTZ) as IS in human plasma. Both the drugs were extracted by simple liquid-liquid extraction with chloroform. The chromatographic separation was performed on a reversed-phase peerless basic C18 column with a mobile phase of methanol-water containing 0.5% formic acid (8:2, v/v). The protonated analyte was quantitated in positive ionization by multiple reaction monitoring with a mass spectrometer. The method was validated over the concentration range of 1-100ng/ml for MPS and 1-15ng/ml AM in human plasma. The MRM transition of m/z 268.10-103.10, m/z 409.10-334.20 and m/z 296.00-205.10 were used to measure MPS, AM and HCTZ (IS), respectively. This method was successfully applied to the pharmacokinetic study of fixed dose combination (FDC) of MPS and AM formulation product after an oral administration to Indian healthy human volunteers. 相似文献
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The cells of the ovarian transmitting tissue of Lilium regaleare papilla shaped and form and epithelium on the placenta.Their ultrastructural organization and differentiation from1 d before to 7 d after anthesis is presented. These placentacells are typical transfer cells with a prominent secretionzone similar to that known from stylar canal cells. After anthesisthe secretion zone continues to grow by addition of vesiclefrom the numerous dictyosomes. Maximum depth of this zone isreached by day 4 after anthesis. The outer surface of the cellwall is distinctly rugged on cell maturation and the outermostlayer is corroded. The ER system undergoes transition from asmooth to a granular condition. Before anthesis there is a centralvacuole which at anthesis is reduced to a system of small vauoles.These are supplemented by autophagic vacuoles formed from theER. Such vacuoles are found near the secretion zone and mayalso fuse with the plasmalemma. The cuticle is sloughed andsecretion commences before anthesis. Accumulations of vesiclesfound in the nucleus and occasional connections between suchvesicles and the inner membrane of the nuclear envelope indicatethe presence of a nuclear network. Protein crystals are presentin the cytoplasm and the nucleus. The starch grains in the plastidsare digested after anthesis, but new ones are formed by days6 and 7.Copyright 1995, 1999 Academic Press Lilium regale, transmitting tissue, placenta, secretion, nuclear reticulum, transfer cells 相似文献
37.
Sapna Sharma Rashmi Aggarwal Anita Yadav Sangeeta Gupta 《Journal of plant biochemistry and biotechnology.》2014,23(3):284-292
Chaetomium globosum is a ubiquitous filamentous fungus having biological control properties. The potential isolates mycoparasitize the pathogen and produce antifungal metabolites which suppress the growth of pathogenic fungi. A proteomics approach was undertaken to separate and identify proteins from a mycoparasitic strain Cg1 of C. globosum under normal and heat shock conditions in order to identify differentially expressed proteins. We developed and standardized the procedure for extraction of total proteins and 2D gel electrophoresis, which resulted in profiling of more than 100 protein spots. 48 proteins were identified by a combination of matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry (MALDI-TOF) and liquid chromatography mass spectrometry (LCMS/MS). Out of total proteins identified, 79 % were hypothetical proteins and 21 % proteins were functionally characterized. Out of total 79 % hypothetical proteins 24 % proteins matched with C. globosum while 18 % proteins matched with Aspergillus spp., 13 % with Coprinopsis cinerea, 10 % with Giberrella zaea, 8 % with Magnaporthe grisea and 5 % with Neurospora crassa and Lodderomyces elonisporus. Some of the functionally characterized proteins included MAP kinase, maltose permease, GTP binding protein, dyenin heavy chain, HET- C2, vacuolar Dig A protein, polyketide synthase, peptide prolyl cis trans isomerase and translation elongation factor. This study has generated a protein reference map for Chaetomium globosum, and being the first report on proteomics studies would greatly help to unravel biocontrol mechanism and its survival under heat stress conditions. 相似文献
38.
This study investigated the functional linkage between food availability and activity behavior in the Palaearctic Indian night migratory blackheaded bunting (Emberiza melanocephala) subjected to artificial light-dark (LD) cycles. Two experiments were performed on photosensitive birds. In the first one, birds were exposed to short days (LD 10/14; Experiment 1A), long days (LD 13/11; Experiment 1B), or increasing daylengths (8 to 13?h light/d; Experiment 1C) and presented with food either for the whole or a restricted duration of the light period. In Experiments 1A and 1B, illumination of the light and dark periods or of the dark period, alone, was changed to assess the influence of the light environment on direct and circadian responses to food cycles. In the second experiment, birds were exposed to LD 12/12 or LD 8/16 with food availability overlapping with the light (light and food presence in phase) or dark period (light and food presence in antiphase). Also, birds were subjected to constant dim light (LL(dim)) to examine the phase of the activity rhythms under synchronizing influence of the food cycles. Similarly, the presentation of food ad libitum (free food; FF) during an experiment examined the effects of the food-restriction regimes on activity rhythms. A continuous measurement of the activity-rest pattern was done to examine both the circadian and direct effects of the food and LD cycles. Measurement of activity at night enabled assessment of the migratory phenotype, premigratory restlessness, or Zugunruhe. The results show that (i) light masked the food effects if they were present together; (ii) birds had a higher anticipatory activity and food intake during restricted feeding conditions; and (iii) food at night alone reduced both the duration and amount of Zugunruhe as compared to food during the day alone. This suggests that food affects both the daily activity and seasonal Zugunruhe, and food cycles act as a synchronizer of circadian rhythms in the absence of dominant natural environmental synchronizers, such as the light-dark cycle. 相似文献
39.
Perantoni AO Timofeeva O Naillat F Richman C Pajni-Underwood S Wilson C Vainio S Dove LF Lewandoski M 《Development (Cambridge, England)》2005,132(17):3859-3871
To bypass the essential gastrulation function of Fgf8 and study its role in lineages of the primitive streak, we have used a new mouse line, T-Cre, to generate mouse embryos with pan-mesodermal loss of Fgf8 expression. Surprisingly, despite previous models in which Fgf8 has been assigned a pivotal role in segmentation/somite differentiation, Fgf8 is not required for these processes. However, mutant neonates display severe renal hypoplasia with deficient nephron formation. In mutant kidneys, aberrant cell death occurs within the metanephric mesenchyme (MM), particularly in the cortical nephrogenic zone, which provides the progenitors for recurring rounds of nephron formation. Prior to mutant morphological changes, Wnt4 and Lim1 expression, which is essential for nephrogenesis, is absent in MM. Furthermore, comparative analysis of Wnt4-null homozygotes reveals concomitant downregulation of Lim1 and diminished tubule formation. Our data support a model whereby FGF8 and WNT4 function in concert to induce the expression of Lim1 for MM survival and tubulogenesis. 相似文献
40.
Mehran Dastmalchi Mark A. Bernards Sangeeta Dhaubhadel 《The Plant journal : for cell and molecular biology》2016,85(6):689-706
Isoflavonoids are specialized plant metabolites, almost exclusive to legumes, and their biosynthesis forms a branch of the diverse phenylpropanoid pathway. Plant metabolism may be coordinated at many levels, including formation of protein complexes, or ‘metabolons’, which represent the molecular level of organization. Here, we have confirmed the existence of the long‐postulated isoflavonoid metabolon by identifying elements of the complex, their subcellular localizations and their interactions. Isoflavone synthase (IFS) and cinnamate 4–hydroxylase (C4H) have been shown to be tandem P450 enzymes that are anchored in the ER, interacting with soluble enzymes of the phenylpropanoid and isoflavonoid pathways (chalcone synthase, chalcone reductase and chalcone isomerase). The soluble enzymes of these pathways, whether localized to the cytoplasm or nucleus, are tethered to the ER through interaction with these P450s. The complex is also held together by interactions between the soluble elements. We provide evidence for IFS interaction with upstream and non‐consecutive enzymes. The existence of such a protein complex suggests a possible mechanism for flux of metabolites into the isoflavonoid pathway. Further, through interaction studies, we identified several candidates that are associated with GmIFS2, an isoform of IFS, in soybean hairy roots. This list provides additional candidates for various biosynthetic and structural elements that are involved in isoflavonoid production. Our interaction studies provide valuable information about isoform specificity among isoflavonoid enzymes, which may guide future engineering of the pathway in legumes or help overcome bottlenecks in heterologous expression. 相似文献