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61.
Anu Mary Varghese Aparna Sharma Poojashree Mishra Kalyan Vijayalakshmi Hindalahalli Chandregowda Harsha Talakad N Sathyaprabha Srinivas MM Bharath Atchayaram Nalini Phalguni Anand Alladi Trichur R Raju 《Clinical proteomics》2013,10(1):19
Background
Potential biomarkers to aid diagnosis and therapy need to be identified for Amyotrophic Lateral Sclerosis, a progressive motor neuronal degenerative disorder. The present study was designed to identify the factor(s) which are differentially expressed in the cerebrospinal fluid (CSF) of patients with sporadic amyotrophic lateral sclerosis (SALS; ALS-CSF), and could be associated with the pathogenesis of this disease.Results
Quantitative mass spectrometry of ALS-CSF and control-CSF (from orthopaedic surgical patients undergoing spinal anaesthesia) samples showed upregulation of 31 proteins in the ALS-CSF, amongst which a ten-fold increase in the levels of chitotriosidase-1 (CHIT-1) was seen compared to the controls. A seventeen-fold increase in the CHIT-1 levels was detected by ELISA, while a ten-fold elevated enzyme activity was also observed. Both these results confirmed the finding of LC-MS/MS. CHIT-1 was found to be expressed by the Iba-1 immunopositive microglia.Conclusion
Elevated CHIT-1 levels in the ALS-CSF suggest a definitive role for the enzyme in the disease pathogenesis. Its synthesis and release from microglia into the CSF may be an aligned event of neurodegeneration. Thus, high levels of CHIT-1 signify enhanced microglial activity which may exacerbate the process of neurodegeneration. In view of the multifold increase observed in ALS-CSF, it can serve as a potential CSF biomarker for the diagnosis of SALS. 相似文献62.
In 59 samples of periphyton and phytoplankton collected in 2002 - 2003 from the Nahal Qishon (Qishon River), northern Israel, we found 178 species from seven divisions of algae and cyanoprocaryotes. Diatoms, clorophytes, and cyanoprocaryotes prevail. Nitzschia and Navicula (Bacillariophyta) are the most abundant. Most of the species are cosmopolitan or widespread, except Lagynion janei (Chrysophyta), which is endemic for the Mediterranean Realm. About 17% of species (26) are new for Israel and five of them represent the first recorded genera: Crinalium endophyticum Crow, Actinocyclus normanii (Gregory) Hustedt, Rhizoclonium hieroglyphicum (Agardh) Kütz (Chlorophyta), Lagynion janei Bourelly, and Stylococcus aureus Chodat. Most of them come from a rare riverine assemblage with red alga Audouinella pygmea, as well as from the estuarine assemblage. Alkaliphiles predominate among the indicators of acidity, with few acidophiles confined to the communities under the impact of industrial wastes. Among the indicators of salinity, most numerous are the oligohalobien-indifferents and species adapted to a moderate salinity level. The relative species richness of ecological groups and the indices of saprobity are correlated with changes in conductivity, pH, and N-nitrate concentration. Indicators of organic pollution fall in the range of betameso- to alfamesosaprobic self-purification grades. Our studies show ecological significance of the Nahal Qishon as a model for a strongly disturbed aquatic ecosystem in the coastal zone of eastern Mediterranean. 相似文献
63.
Intensive nitrogen loss over the Omani Shelf due to anammox coupled with dissimilatory nitrite reduction to ammonium 总被引:1,自引:0,他引:1
Marlene M Jensen Phyllis Lam Niels Peter Revsbech Birgit Nagel Birgit Gaye Mike SM Jetten Marcel MM Kuypers 《The ISME journal》2011,5(10):1660-1670
A combination of stable isotopes (15N) and molecular ecological approaches was used to investigate the vertical distribution and mechanisms of biological N2 production along a transect from the Omani coast to the central–northeastern (NE) Arabian Sea. The Arabian Sea harbors the thickest oxygen minimum zone (OMZ) in the world''s oceans, and is considered to be a major site of oceanic nitrogen (N) loss. Short (<48 h) anoxic incubations with 15N-labeled substrates and functional gene expression analyses showed that the anammox process was highly active, whereas denitrification was hardly detectable in the OMZ over the Omani shelf at least at the time of our sampling. Anammox was coupled with dissimilatory nitrite reduction to ammonium (DNRA), resulting in the production of double-15N-labeled N2 from 15NO2−, a signal often taken as the lone evidence for denitrification in the past. Although the central–NE Arabian Sea has conventionally been regarded as the primary N-loss region, low potential N-loss rates at sporadic depths were detected at best. N-loss activities in this region likely experience high spatiotemporal variabilities as linked to the availability of organic matter. Our finding of greater N-loss associated with the more productive Omani upwelling region is consistent with results from other major OMZs. The close reliance of anammox on DNRA also highlights the need to take into account the effects of coupling N-transformations on oceanic N-loss and subsequent N-balance estimates. 相似文献
64.
A novel trisarylborane–Bi(III) complex, tris(4‐(dimesitylboryl)phenyl)bismuthine [Bi(PhBMes2)3], in which (Ph = phenyl, and Mes = mesityl), was synthesized via the reaction of bismuth (III) chloride (BiCl3) with three equivalents of lithiated (4‐bromophenyl)‐ dimesitylborane [BrPhBMes2]. The new trisarylbismuthine was characterized by elemental analysis, ultraviolet–visible (UV–vis) spectroscopy, and NMR (1H and 13C) spectroscopy. The molecular structure of Bi(PhBMes2)3 in the solid state was determined using single‐crystal X‐ray diffraction analysis, which showed short intermolecular C–H···H–C contact. The complex is a fluorescent emitter (λmax = 395 nm) at room temperature and a phosphorescent emitter (λmax = 423 nm) at 77 K, which displayed a long lifetime of 495 ms. The UV–vis transitions were investigated using density function theory (DFT) and time‐dependent (TD)‐DFT calculations. Natural bond orbital analysis showed that the bismuth (III) center was mainly Lewis acidic in nature. 相似文献
65.
66.
Mohankrishna Dalvoy Vasudevarao Pushpak Mizar Sujata Kumari Somnath Mandal Soumik Siddhanta Mahadeva MM Swamy Stephanie Kaypee Ravindra C Kodihalli Amrita Banerjee Chandrabhas Naryana Dipak Dasgupta Tapas K. Kundu 《The Journal of biological chemistry》2014,289(11):7702-7717
Hydroxynaphthoquinone-based inhibitors of the lysine acetyltransferase KAT3B (p300), such as plumbagin, are relatively toxic. Here, we report that free thiol reactivity and redox cycling properties greatly contribute to the toxicity of plumbagin. A reactive 3rd position in the naphthoquinone derivatives is essential for thiol reactivity and enhances redox cycling. Using this clue, we synthesized PTK1, harboring a methyl substitution at the 3rd position of plumbagin. This molecule loses its thiol reactivity completely and its redox cycling ability to a lesser extent. Mechanistically, non-competitive, reversible binding of the inhibitor to the lysine acetyltransferase (KAT) domain of p300 is largely responsible for the acetyltransferase inhibition. Remarkably, the modified inhibitor PTK1 was a nearly non-toxic inhibitor of p300. The present report elucidates the mechanism of acetyltransferase activity inhibition by 1,4-naphthoquinones, which involves redox cycling and nucleophilic adduct formation, and it suggests possible routes of synthesis of the non-toxic inhibitor. 相似文献
67.
Chemical composition and antimicrobial activity of volatile compounds of Tamarix boveana (Tamaricaceae) 总被引:2,自引:0,他引:2
Saïdana D Mahjoub MA Boussaada O Chriaa J Chéraif I Daami M Mighri Z Helal AN 《Microbiological research》2008,163(4):445-455
The chemical composition of the Tamarix boveana volatile oils obtained from the whole aerial part, flowers, leaves and stems by steam distillation was analysed using gas chromatograph (GC)-flame ionization detectors (FID) and GC-MS. Sixty-two components were identified. Hexadecanoic acid (18.14%), docosane (13.34%), germacrene D (7.68%), fenchyl acetate (7.34%), Benzyl benzoate (4.11%) were found to be the major components in the whole aerial parts. This composition differed according to the tested part: 2.4 Nonadienal was the main compound in the flowers (12.13%) while germacrene D was the major component in leaves (31.43%) and hexadecanoic acid in the stems (13.94%). To evaluate in vitro antimicrobial activity, all volatile oils were tested against six Gram-positive and Gram-negative bacteria and four fungi. The T. boveana volatile oils exhibited an interesting antibacterial activity against all strains tested except Pseudomonas aeruginosa but no antifungal activity was detected. 相似文献
68.
Afforestation is a recommended practice to mitigate global warming. However, their implementation may generate undesirable impacts, mostly if exotic species are used. Plantations of Pinus radiata D Don in Ventania (Bs. As., Argentina) soils showed notorious increments of extractable P (Pe), which could affect the dynamic of this element as well as the degree of phosphorus saturation (GSPBray). The objectives of this study were: i) to quantify the GSPBray in Mollisols afforested with P. radiata comparing the results with those coming from adjacent, natural grassland areas (base line); ii) to evaluate the potential environmental risk induced by afforestation through the identification of a change point (PC) in the GSPBray indicative of a phosphate leaching increment. Treatments included mature stands of P. radiata (TB) and adjacent areas with natural grassland vegetation (TP). Samples were taken at 0-15; 15-30 and 30-45 cm soil depth, and texture, pH, total organic carbon (COT), Pe, soluble reactive phosphorus (PSR), phosphorus sorption index (ISP) and GSPBray were determined. The results showed a significant acidification in TB and an increase in the COT stock, indicating an additional atmospheric CO2 sequestration by the trees. The Pe and PSR values were notoriously higher in TB, and they were reflected in a significant increment in the GSPBray with respect to TP. The detection of a significant PC in the GSPBray-PSR regression indicates higher chances of phosphate leaching in the forest stands, which could reach water courses, lakes and artificial reservoirs promoting their eutrophication. Because of the potential environmental pollution risk of biologic origin derived from the afforestation with P. radiata in Mollisols areas, their inclusion in clean development practices must be reconsidered. 相似文献
69.
Evidence of Three Subspecies in Trifolium nigrescens Viv. 总被引:1,自引:0,他引:1
Williams Warren M.; Ansari Helal A.; Ellison Nick W.; Hussain Syed Wajid 《Annals of botany》2001,87(5):683-691
Germplasm accessions of Trifolium nigrescens Viv. were foundto belong to three distinct taxa which differed in morphology,hybrid seed-set in crosses among themselves and with white clover(T. repens L.), chromosomal distribution of rDNA genes, andrDNA internally transcribed spacer (ITS) region sequences. Thesetaxonomic groups correspond with T. nigrescens ssp. nigrescens,T. nigrescens ssp. petrisavii var.petrisavii and var. meneghinianum.The existence of var. meneghinianum has been rejected or ignoredin recent taxonomic treatments. The present study indicatesthat it is very distinctive and warrants at least subspeciesstatus. Phylogenetic analysis based on ITS sequences and podmorphology placed ssp. nigrescens as progenitor to the others.ITS sequences placed white clover closer to ssp. petrisaviibut neither DNA sequences nor rDNA chromosome locations clearlyshowed whether var. petrisavii or var. meneghinianum was closerto white clover. In contrast, results of hybridization studiesshowed that ssp. nigrescens gave full seed-set when pollinatedwith T. repens whereas both ssp. petrisavii var. petrisaviiand ssp. petrisavii var. meneghinianum gave poor seed-set. Allthree taxa showed close relationships with white clover andnone can clearly be shown to be a direct ancestor of T. repens.Copyright 2001 Annals of Botany Company Fabaceae, Trifolium nigrescens, Trifolium repens, internal transcribed spacer region (ITS), nuclear ribosomal DNA, interspecific hybridization 相似文献
70.
Mohamed A. Helal Amar G. Chittiboyina Mitchell A. Avery 《Bioorganic & medicinal chemistry letters》2019,29(24):126741
MCH receptor is a G protein-coupled receptor with two subtypes R1 and R2. Many studies have demonstrated the role of MCH-R1 in feeding and energy homeostasis. It has been proven that oral administration of small molecule MCH-R1 antagonists significantly reduces food intake and causes a dose-dependent weight loss. In this study, two ligand-based pharmacophores were developed and validated based on recently published MCH-R1 antagonists with diverse structures. Successful pharmacophores had one hydrogen bond acceptor, one positive ionizable, one ring aromatic and two or three hydrophobic groups. These 3D-QSAR models were used for virtual screening of the ZINC chemical database resulting in the identification of nine compounds with more than 50% displacement of radiolabeled MCH at a 20 μM concentration. Moreover, four of these compounds showed antagonistic activities in Aequorin functional assay, including MH-3 which is the first MCH-R1 antagonist based on a diazaspiro[4.5]decane scaffold. The most active compounds were also docked into our previously published MCH-R1 homology model to gain insights into their binding determinants. These compounds could represent a viable starting scaffold for the design of potent MCH-R1 antagonists with improved pharmacokinetic properties as an effective treatment for obesity. 相似文献