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71.
Mayank Singh Clayton R. Hunt Raj K. Pandita Rakesh Kumar Chin-Rang Yang Nobuo Horikoshi Robert Bachoo Sara Serag Michael D. Story Jerry W. Shay Simon N. Powell Arun Gupta Jessie Jeffery Shruti Pandita Benjamin P. C. Chen Dorothee Deckbar Markus L?brich Qin Yang Kum Kum Khanna Howard J. Worman Tej K. Pandita 《Molecular and cellular biology》2013,33(16):3390
72.
Lisa Noelle Cooper J. G.M. Thewissen Sunil Bajpai B. N. Tiwari 《Historical Biology》2013,25(3):279-310
Raoellids are small, raccoon-sized Eocene artiodactyls, closely related to archaic cetaceans (archaeocetes) that have poor representation of postcranial elements in the fossil record. Little is known of the aquatic and terrestrial locomotor affinities of raoellids due to the paucity of their fossil record, leaving a critical gap in our understanding of the earliest portion of the artiodactyl marine invasion. To address this gap, a comparative morphological analysis of the postcranial elements was undertaken based on newly recovered elements of the raoellid Indohyus, archaeocetes and extant artiodactyls. Greater than 200 postcranial elements of Indohyus were described, and some limb element cross-sections were visualised via paleohistological thin sections and CT scans. Results show that during terrestrial locomotion, Indohyus probably had a digitigrade posture and mediolaterally stabilised limbs that functioned mostly in flexion and extension within the parasagittal plane. Quantification of midshaft cross-sectional area for some elements of Indohyus showed an osteosclerotic cortex, a skeletal characteristic associated with aquatic behaviours. Indohyus may represent a critical intermediate in the evolution of the cetacean terrestrial-to-aquatic body plan, as it bears gracile postcranial element proportions similar to a terrestrial artiodactyl but also an incipient form of osteosclerosis compared to pakicetid archaeocetes. 相似文献
73.
Gitanjali Tandon Sarika Jaiswal M.A. Iquebal Sunil Kumar Sukhdeep Kaur Anil Rai 《Journal of biomolecular structure & dynamics》2013,31(10):2180-2191
Biotic stress is a major cause of heavy loss in grape productivity. In order to develop biotic stress-resistant grape varieties, the key defense genes along with its pathway have to be deciphered. In angiosperm plants, lipase-like protein phytoalexin deficient 4 (PAD4) is well known to be essential for systemic resistance against biotic stress. PAD4 functions together with its interacting partner protein enhanced disease susceptibility 1 (EDS1) to promote salicylic acid (SA)-dependent and SA-independent defense pathway. Existence and structure of key protein of systemic resistance EDS1 and PAD4 are not known in grapes. Before SA pathway studies are taken in grape, molecular evidence of EDS1: PAD4 complex is to be established. To establish this, EDS1 protein sequence was retrieved from NCBI and homologous PAD4 protein was generated using Arabidopsis thaliana as template and conserved domains were confirmed. In this study, computational methods were used to model EDS1 and PAD4 and simulated the interactions of EDS1 and PAD4. Since no structural details of the proteins were available, homology modeling was employed to construct three-dimensional structures. Further, molecular dynamic simulations were performed to study the dynamic behavior of the EDS1 and PAD4. The modeled proteins were validated and subjected to molecular docking analysis. Molecular evidence of stable complex of EDS1:PAD4 in grape supporting SA defense pathway in response to biotic stress is reported in this study. If SA defense pathway genes are explored, then markers of genes involved can play pivotal role in grape variety development especially against biotic stress leading to higher productivity. 相似文献
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75.
Arun P. Chandrasekharappa Sangamesh E. Badiger Pramod K. Dubey Sunil K. Panigrahi Sekhar Reddy V.V.V. Manukonda 《Bioorganic & medicinal chemistry letters》2013,23(9):2579-2584
A series of benzoxazole compounds containing oxamic acid were synthesized and screened for the PTP1B inhibition. Compound 31d showed best biochemical potency (Ki) of 6.7 μM. Structure–activity relationship were explained with the help of molecular modeling approach. 相似文献
76.
Hyosung Lee Alexander S. Gold Xiao-Fang Yang Rajesh Khanna Harold Kohn 《Bioorganic & medicinal chemistry》2013,21(24):7655-7662
Several antiepileptic drugs exert their activities by inhibiting Na+ currents. Recent studies demonstrated that compounds containing a biaryl-linked motif (Ar-X-Ar′) modulate Na+ currents. We, and others, have reported that compounds with an embedded benzyloxyphenyl unit (ArOCH2Ar′, OCH2 = X) exhibit potent anticonvulsant activities. Here, we show that benzyloxybenzylammonium chlorides (+H3NCH2C6H4OCH2Ar′ Cl?) displayed notable activities in animal seizure models. Electrophysiological studies of 4-(2′-trifluoromethoxybenzyloxy)benzylammonium chloride (9) using embryonic cortical neurons demonstrated that 9 promoted both fast and slow inactivation of Na+ channels. These findings suggest that the potent anticonvulsant activities of the earlier compounds were due, in part, to the benzyloxyphenyl motif and provide support for the use of the biaryl-linked pharmacophore in future drug design efforts. 相似文献
77.
78.
Sunali Khanna A.C. Udas G. Kiran Kumar S. Suvarna F.R. Karjodkar 《Journal of trace elements in medicine and biology》2013,27(4):307-311
Oral cancer is a major cause of cancer morbidity and mortality worldwide and is prevalent in most areas where tobacco related practices are observed. Essential elements play a role in many biochemical reactions as a micro-source and there is growing evidence that their concentrations are altered on the onset and progress of malignant disease. In this study the levels of copper (Cu), zinc (Zn), selenium (Se) and molybdenum (Mo) in serum of patients with oral sub mucous fibrosis (OSMF) (n = 30) and oral squamous cell carcinoma (OSCC) (n = 30); were determined and the alterations of these critical parameters were analyzed in comparison with controls (n = 30) to identify predictors amongst these parameters for disease occurrence and progression. The serum Cu and Zn were established using Flame Atomic Absorption Spectrometry. Serum estimation of Se and Mo was done by graphite furnace atomic absorption spectrometry (GFAAS). Data analysis revealed a marked, progressive and significant increase in Cu levels in precancer (OSMF) and cancer (OSCC) groups as compared to the normal group. The level of Zn in serum was slightly elevated in OSMF and OSCC though not statistically significant. Cu/Zn ratio was slightly but not significantly elevated. Serum levels of Se and Mo were significantly decreased in the precancer and cancer groups as compared to the normals. 相似文献
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