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21.
Varying the parameters such as agitation time, dye concentration, adsorbent dose, pH and temperature carried out the potential feasibility of thermally activated coir pith carbon prepared from coconut husk for removal of methylene blue. Greater percentage of dye was removed with decrease in the initial concentration of dye and increase in amount of adsorbent used. Kinetic study showed that the adsorption of dye on coir pith carbon was a gradual process. Lagergren first-order, second-order, intra particle diffusion model and Bangham were used to fit the experimental data. Equilibrium isotherms were analysed by Langmuir, Freundlich, Dubnin-Radushkevich, and Tempkin isotherm. The adsorption capacity was found to be 5.87 mg/g by Langmuir isotherm for the particle size 250-500 microm. The equilibrium time was found to be 30 and 60 min for 10 and 20 mg/L and 100 min for 30, 40 mg/L dye concentrations, respectively. A maximum removal of 97% was obtained at natural pH 6.9 for an adsorbent dose of 100 mg/50 mL and 100% removal was obtained for an adsorbent dose of 600 mg/50 mL of 10 mg/L dye concentration. The pH effect and desorption studies suggest that chemisorption might be the major mode of the adsorption process. The change in entropy (DeltaS0) and heat of adsorption (DeltaH0) of coir pith carbon was estimated as 117.20 J/mol/K and 30.88 kJ/mol, respectively. The high negative value of change in Gibbs free energy indicates the feasible and spontaneous adsorption of methylene blue on coir pith carbon. 相似文献
22.
Lamesch P Li N Milstein S Fan C Hao T Szabo G Hu Z Venkatesan K Bethel G Martin P Rogers J Lawlor S McLaren S Dricot A Borick H Cusick ME Vandenhaute J Dunham I Hill DE Vidal M 《Genomics》2007,89(3):307-315
Complete sets of cloned protein-encoding open reading frames (ORFs), or ORFeomes, are essential tools for large-scale proteomics and systems biology studies. Here we describe human ORFeome version 3.1 (hORFeome v3.1), currently the largest publicly available resource of full-length human ORFs (available at ). Generated by Gateway recombinational cloning, this collection contains 12,212 ORFs, representing 10,214 human genes, and corresponds to a 51% expansion of the original hORFeome v1.1. An online human ORFeome database, hORFDB, was built and serves as the central repository for all cloned human ORFs (http://horfdb.dfci.harvard.edu). This expansion of the original ORFeome resource greatly increases the potential experimental search space for large-scale proteomics studies, which will lead to the generation of more comprehensive datasets. 相似文献
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Microspheres of tramadol hydrochloride (TM) for oral delivery were prepared by complex coacervation method without the use
of chemical cross-linking agents such as glutaraldehyde to avoid the toxic reactions and other undesirable effects of the
chemical cross-linking agents. Alternatively, ionotropic gelation was employed by using sodium-tripolyphosphate as cross-linking
agent. Chitosan and gelatin B were used as polymer and copolymer, respectively. All the prepared microspheres were subjected
to various physicochemical studies, such as drug–polymer compatibility by thin layer chromatography (TLC) and Fourier transform
infrared (FTIR) spectroscopy, surface morphology by scanning electron microscopy, frequency distribution, drug entrapment
efficiency, in vitro drug release characteristics and release kinetics. The physical state of drug in the microspheres was determined by differential
scanning calorimetry (DSC) and X-ray diffractometry (XRD). TLC and FTIR studies indicated no drug–polymer incompatibility.
All the microspheres showed initial burst release followed by a fickian diffusion mechanism. DSC and XRD analysis indicated
that the TM trapped in the microspheres existed in an amorphous or disordered-crystalline status in the polymer matrix. From
the preliminary trials, it was observed that it may be possible to formulate TM microspheres by using biodegradable natural
polymers such as chitosan and gelatin B to overcome the drawbacks of TM and to increase the patient compliance. 相似文献
25.
Kavitha P Ramesh R Bupesh G Stalin A Subramanian P 《In vitro cellular & developmental biology. Animal》2011,47(10):698-706
The potential protective role of Tribulus terrestris in acetaminophen-induced hepatotoxicity in Oreochromis mossambicus was investigated. The effect of oral exposure of acetaminophen (500 mg/kg) in O. mossambicus at 24-h duration was evaluated. The plant extract (250 mg/kg) showed a remarkable hepatoprotective activity against acetaminophen-induced
hepatotoxicity. It was judged from the tissue-damaging level and antioxidant levels in liver, gill, muscle and kidney tissues.
Further acetaminophen impact induced a significant rise in the tissue-damaging level, and the antioxidant level was discernible
from the enzyme activity modulations such as glutamate oxaloacetic transaminase, glutamate pyruvic transaminase, alkaline
phosphatase, acid phosphatase, glucose-6-phosphate dehydrogenase, lactate dehydrogenase, superoxide dismutase, catalase, glutathione
peroxidase, glutathione reductase, glutathione S-transferase, lipid peroxidase and reduced glutathione. The levels of all
these enzymes have significantly (p < 0.05) increased in acetaminophen-treated fish tissues. The elevated levels of these enzymes were significantly controlled
by the treatment of T. terrestris extract (250 kg/mg). Histopathological changes of liver, gill and muscle samples were compared with respective controls.
The results of the present study specify the hepatoprotective and antioxidant properties of T. terrestris against acetaminophen-induced toxicity in freshwater fish, O. mossambicus. 相似文献
26.
Sharif-Paghaleh E Sunassee K Tavaré R Ratnasothy K Koers A Ali N Alhabbab R Blower PJ Lechler RI Smyth LA Mullen GE Lombardi G 《PloS one》2011,6(10):e25857
Regulatory T cells (Tregs) were identified several years ago and are key in controlling autoimmune diseases and limiting immune responses to foreign antigens, including alloantigens. In vivo imaging techniques including intravital microscopy as well as whole body imaging using bioluminescence probes have contributed to the understanding of in vivo Treg function, their mechanisms of action and target cells. Imaging of the human sodium/iodide symporter via Single Photon Emission Computed Tomography (SPECT) has been used to image various cell types in vivo. It has several advantages over the aforementioned imaging techniques including high sensitivity, it allows non-invasive whole body studies of viable cell migration and localisation of cells over time and lastly it may offer the possibility to be translated to the clinic. This study addresses whether SPECT/CT imaging can be used to visualise the migratory pattern of Tregs in vivo. Treg lines derived from CD4(+)CD25(+)FoxP3(+) cells were retrovirally transduced with a construct encoding for the human Sodium Iodide Symporter (NIS) and the fluorescent protein mCherry and stimulated with autologous DCs. NIS expressing self-specific Tregs were specifically radiolabelled in vitro with Technetium-99m pertechnetate ((99m)TcO(4)(-)) and exposure of these cells to radioactivity did not affect cell viability, phenotype or function. In addition adoptively transferred Treg-NIS cells were imaged in vivo in C57BL/6 (BL/6) mice by SPECT/CT using (99m)TcO(4)(-). After 24 hours NIS expressing Tregs were observed in the spleen and their localisation was further confirmed by organ biodistribution studies and flow cytometry analysis. The data presented here suggests that SPECT/CT imaging can be utilised in preclinical imaging studies of adoptively transferred Tregs without affecting Treg function and viability thereby allowing longitudinal studies within disease models. 相似文献
27.
Histone variants meet their match 总被引:8,自引:0,他引:8
A fascinating aspect of how chromatin structure impacts on gene expression and cellular identity is the transmission of information from mother to daughter cells, independently of the primary DNA sequence. This epigenetic information seems to be contained within the covalent modifications of histone polypeptides and the distinctive characteristics of variant histone subspecies. There are specific deposition pathways for some histone variants, which provide invaluable mechanistic insights into processes whereby the major histones are exchanged for their more specialized counterparts. 相似文献
28.
The predicted coiled-coil domain of myosin 10 forms a novel elongated domain that lengthens the head
Knight PJ Thirumurugan K Xu Y Wang F Kalverda AP Stafford WF Sellers JR Peckham M 《The Journal of biological chemistry》2005,280(41):34702-34708
Myosin 10 contains a region of predicted coiled coil 120 residues long. However, the highly charged nature and pattern of charges in the proximal 36 residues appear incompatible with coiled-coil formation. Circular dichroism, NMR, and analytical ultracentrifugation show that a synthesized peptide containing this region forms a stable single alpha-helix (SAH) domain in solution and does not dimerize to form a coiled coil even at millimolar concentrations. Additionally, electron microscopy of a recombinant myosin 10 containing the motor, the three calmodulin binding domains, and the full-length predicted coiled coil showed that it was mostly monomeric at physiological protein concentration. In dimers the molecules were joined only at their extreme distal ends, and no coiled-coil tail was visible. Furthermore, the neck lengths of both monomers and dimers were much longer than expected from the number of calmodulin binding domains. In contrast, micrographs of myosin 5 heavy meromyosin obtained under the same conditions clearly showed a coiled-coil tail, and the necks were the predicted length. Thus the predicted coiled coil of myosin 10 forms a novel elongated structure in which the proximal region is a SAH domain and the distal region is a SAH domain (or has an unknown extended structure) that dimerizes only at its end. Sequence comparisons show that similar structures may exist in the predicted coiled-coil domains of myosins 6 and 7a and MyoM and could function to increase the size of the working stroke. 相似文献
29.
Kang J DiBenedetto B Narayan K Zhao H Der SD Chambers CA 《Journal of immunology (Baltimore, Md. : 1950)》2004,173(4):2307-2314
30.
We describe a novel murine gene rudhira that is expressed at high levels in embryonic stem cells and is restricted to blood islands and the erythroid lineage during embryonic development. Rudhira is expressed in angiogenic precursors but is excluded from the differentiated endothelium. Rudhira-expressing cells are seen in close proximity to endothelial cells in angiogenic blood vessels. Rudhira encodes a predicted cytoplasmic WD40 protein that is 98% identical to human BCAS3. The gene encoding BCAS3 maps to a breakpoint of hematological neoplasms on human chromosome 17q23, but its expression and function remain to be determined. We demonstrate that mouse Rudhira is a novel marker for analysis of the erythroid lineage. 相似文献