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Xeroderma pigmentosum-Cockayne syndrome (XP-CS) includes facial freckling and early skin cancers typical of XP and some features typical of CS, such as mental retardation, spasticity, short stature, and hypogonadism. XP-CS does not include skeletal involvement, the facial phenotype of CS, or CNS demyelination and calcifications. We present a rare patient whose genome probably harbored a specific combination of mutations producing a rare double syndrome of XP-CS, with facial phenotype of CS, and CNS demyelination. 相似文献
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K Nagaiah P MacDonnell G Guroff 《Biochemical and biophysical research communications》1977,75(4):832-837
The addition of dexamethasone and nerve growth factor to organ cultures of superior cervical ganglia from young rats induces the synthesis of tyrosine hydroxylase. The combination of nerve growth factor and dexamethasone produces a differential rate of tyrosine hydroxylase synthesis which approaches that obtained by the administration of nerve growth factor. 相似文献
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This work proposes an optimal control approach for the termination of re-entry waves in cardiac electrophysiology. The control enters as an extracellular current density into the bidomain equations which are well established model equations in the literature to describe the electrical behavior of the cardiac tissue. The optimal control formulation is inspired, in part, by the dynamical systems behavior of the underlying system of differential equations. Existence of optimal controls is established and the optimality system is derived formally. The numerical realization is described in detail and numerical experiments, which demonstrate the capability of influencing and terminating reentry phenomena, are presented. 相似文献
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Sampath Kumar Bandari Bal Raju Kammari Jyothi Madda Nagaiah Kommu Arunapriya Lakkadi Srimai Vuppala Parthasarathy Tigulla 《Bioorganic & medicinal chemistry letters》2017,27(5):1256-1260
New chromeno carbamodithioates (7a-i), have been synthesized from 2, 3-dimethyl-7-(oxiran-2-ylmethoxy)-4H-chromen-4-one (5), carbondisulphide and commercially available acyclic and cyclic secondary amines in acetonitrile with good to excellent yields. The free radical scavenging activity of novel chromone-carbamodithioate analogues was quantitatively estimated by spectrophotometric method. Whereas, molecular docking studies were performed with the active site of cyclooxygenase-2 to identify hydrogen bonding, hydrophobic and ionic interactions between protein and ligands. The compounds 7g and 7h demonstrated potent antioxidant activity with IC50 of 1.405 ± 0.019 mM and 1.382 ± 0.35 mM respectively compared to Ascorbic acid. 相似文献
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We confirmed the occurrence of the insect TTAGG telomeric repeats in the mealybug Planococcus lilacinus, a radiation-resistant coccid, by single primer polymerase chain reaction (PCR) and Southern hybridization. Analysis of Bal31 nuclease-digested DNA by Southern hybridization and chromosomes by FISH suggests that these repeats occur mainly at the
ends of the chromosomes. However, sequence analysis of the PCR products of TTAGG-associated sequences from genomic DNA showed
their interstitial occurrence and association with certain unrelated low-copy repeats. Because of their shorter length, the
interstitial TTAGG sequences were detectable by primed in situ hybridizations but not by FISH. Analysis of chromosomes recovered
after irradiation by fluorescent in situ hybridization suggested acquisition of TTAGG repeats at a majority of the healed
ends. We also observed mild telomerase activity in unirradiated insects which was further enhanced after irradiation. Taken
together, these results suggest that the mealybug has an efficient mechanism of formation of TTAGG repeats at radiation-induced
chromosome ends and constitutively active telomerase may be a feature associated with rapid recovery of chromosome ends damaged
by ionizing radiation. 相似文献
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Martin Rückl Ian Parker Jonathan S. Marchant Chamakuri Nagaiah Friedrich W. Johenning Sten Rüdiger 《PLoS computational biology》2015,11(1)
The oscillating concentration of intracellular calcium is one of the most important examples for collective dynamics in cell biology. Localized releases of calcium through clusters of inositol 1,4,5-trisphosphate receptor channels constitute elementary signals called calcium puffs. Coupling by diffusing calcium leads to global releases and waves, but the exact mechanism of inter-cluster coupling and triggering of waves is unknown. To elucidate the relation of puffs and waves, we here model a cluster of IP3R channels using a gating scheme with variable non-equilibrium IP3 binding. Hybrid stochastic and deterministic simulations show that puffs are not stereotyped events of constant duration but are sensitive to stimulation strength and residual calcium. For increasing IP3 concentration, the release events become modulated at a timescale of minutes, with repetitive wave-like releases interspersed with several puffs. This modulation is consistent with experimental observations we present, including refractoriness and increase of puff frequency during the inter-wave interval. Our results suggest that waves are established by a random but time-modulated appearance of sustained release events, which have a high potential to trigger and synchronize activity throughout the cell. 相似文献
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Naveen Kumar Bejjanki Akkaladevi Venkatesham Jyothi Madda Nagaiah Kommu Sujitha Pombala C. Ganesh Kumar Kothakonda Rajendra Prasad Jagadeesh Babu Nanubolu 《Bioorganic & medicinal chemistry letters》2013,23(14):4061-4066
New cis-fused chromeno pyrano[4,3-c]isoxazole derivatives have been synthesized by intramolecular [1,3]-cycloaddition of the nitrones generated in situ from hydroxylamine derivatives and 7-O-prenyl derivatives of 8-formyl-2,3-disubstituted chromenones using PEG-400 as a reaction medium under catalyst-free conditions good to excellent yields. The structures were established by spectroscopic data and further confirmed by X-ray diffraction analysis. The results showed that compounds 4b, 4c, 4d, 4e and 4k exhibit very potent antiproliferative activity against MDA-MB-231 breast cancer cells. Compounds 4a, 4c, 4e, 4i and 4k displayed potent inhibitory activity against human MCF-7 breast cancer cell lines. Compounds 4h and 4i exhibited significant anti-proliferative activity against human cervical cancer cell line, HeLa. While 4b, 4d and 4j were active against human lung cancer cell line, A549. In addition, Compound 4j was found to be the most promising against A549 (Lung cancer) with IC50 value of 0.194 μM. 相似文献
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Takeyuki Ikeno Paul C. MacDonnell K. Nagaiah Gordon Guroff 《Biochemical and biophysical research communications》1978,82(3):957-963
The intraventricular administration of nerve growth factor causes a marked increase in the activity of ornithine decarboxylase in rat brain. This increase is much smaller in adrenalectomized rats. Dexamethasone and corticosterone, administered either systemically or intraventricularly, are able to restore the ability of nerve growth factor to induce ornithine decarboxylase. The steroids must be given at least three hours before the nerve growth factor to be fully effective. 相似文献