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151.
Salyakina D Cukier HN Lee JM Sacharow S Nations LD Ma D Jaworski JM Konidari I Whitehead PL Wright HH Abramson RK Williams SM Menon R Haines JL Gilbert JR Cuccaro ML Pericak-Vance MA 《PloS one》2011,6(10):e26049
Copy number variations (CNVs) are a major cause of genetic disruption in the human genome with far more nucleotides being altered by duplications and deletions than by single nucleotide polymorphisms (SNPs). In the multifaceted etiology of autism spectrum disorders (ASDs), CNVs appear to contribute significantly to our understanding of the pathogenesis of this complex disease. A unique resource of 42 extended ASD families was genotyped for over 1 million SNPs to detect CNVs that may contribute to ASD susceptibility. Each family has at least one avuncular or cousin pair with ASD. Families were then evaluated for co-segregation of CNVs in ASD patients. We identified a total of five deletions and seven duplications in eleven families that co-segregated with ASD. Two of the CNVs overlap with regions on 7p21.3 and 15q24.1 that have been previously reported in ASD individuals and two additional CNVs on 3p26.3 and 12q24.32 occur near regions associated with schizophrenia. These findings provide further evidence for the involvement of ICA1 and NXPH1 on 7p21.3 in ASD susceptibility and highlight novel ASD candidates, including CHL1, FGFBP3 and POUF41. These studies highlight the power of using extended families for gene discovery in traits with a complex etiology. 相似文献
152.
153.
Background
Rupture of the fetal membranes is a common harbinger of imminent labor and delivery. Telomere shortening is a surrogate for oxidative stress (OS) and senescence. Fetal leukocyte and placental membrane DNA telomere lengths were evaluated to determine their association with preterm prelabor rupture of the membranes (pPROM) or spontaneous preterm births with intact membranes (PTB), compared to term birth.Methods
Telomere lengths were quantified in cord blood leukocytes (n = 133) from three major groups: 1) pPROM (n = 28), 2) PTB (n = 69) and 3) uncomplicated full term births (controls, n = 35), using real-time quantitative PCR. Placental membrane specimens (n = 18) were used to correlate fetal leukocyte and placental telomere lengths. Telomere length differences among the groups were analyzed by ANOVA. Pearson correlation coefficients determined relationships between leukocyte and placental membrane telomere lengths.Results
In pregnancies with intact membranes, fetal leukocyte telomere length was inversely proportional to gestational age. The mean telomere length decreased as gestation progressed, with the shortest at term. pPROM had telomere lengths (9962±3124 bp) that were significantly shorter than gestational age-matched PTB (11546±4348 bp, p = 0.04), but comparable to term births (9011±2497 bp, p = 0.31). Secondary analyses revealed no effects of race (African American vs. Caucasian) or intraamniotic infection on telomere length. A strong Pearson''s correlation was noted between fetal leukocyte and placental membrane telomere lengths (ρ = 0.77; p<0.01).Conclusions
Fetal leukocyte telomere length is reduced in pPROM compared to PTB but is similar to term births. pPROM represents a placental membrane disease likely mediated by OS-induced senescence. 相似文献154.
155.
Neetu Jha Palanisamy Ramesh Elena Bekyarova Mikhail E. Itkis Robert C. Haddon 《Liver Transplantation》2012,2(4):438-444
A high energy density supercapacitor device is reported that utilizes hybrid carbon electrodes and the ionic liquid, 1‐butyl‐3‐methylimidazolium tetrafluoroborate (BMIMBF4) as an electrolyte. The hybrid electrodes are prepared from reduced graphite oxide (rGO) and purified single‐walled carbon nanotubes (SWCNTs). A simple casting technique gives the hybrid structure with optimum porosity and functionality that provides high energy and power densities. The combination of SWCNTs and rGO in a weight ratio of 1:1 is found to afford a specific capacitance of 222 F g?1 and an energy density of 94 Wh kg?1 at room temperature. 相似文献
156.
Dong Ho Park Jayachandran Venkatesan Se-Kwon Kim Venkatachalm Ramkumar Paramasivam Parthiban 《Bioorganic & medicinal chemistry letters》2012,22(20):6362-6367
The biological importance of antioxidants influenced to synthesize some curcumin-related compounds as potential antioxidants. Accordingly, a series of 2,4-diaryl-3-azabicyco[3.3.1]nonan-9-ones were synthesized with polyphenolic and/or polymethoxyphenyl groups by modified Mannich condensations. The yield was significantly improved using BF3·SiO2 as heterogeneous catalyst under mild conditions. Stereochemistry of all the synthesized compounds was established as twin-chair with an equatorial disposition of the aryl groups, through their NMR and XRD interpretations. The ABNs 8 (curcumin analog) and 10 (bis-demethoxycurcumin analog) showed an effective profile over curcumin, α-tocopherol, and vitamin C by chemical methods. Further, the efficiency of one of the active molecules, ABN 10, was demonstrated by its intracellular ROS inhibition activity on RAW 264.7 macrophage cells by FACS analysis in dose-dependent manner. 相似文献
157.
158.
Palanisamy Uma Maheswari 《Inorganica chimica acta》2004,357(4):901-912
The interaction of a series of mixed ligand complexes of the type [Ru(NH3)4(diimine)]Cl2, where diimine=2,2′-bipyridine (bipy), 1,10-phenanthroline (phen), 5,6-dimethyl-1,10-phenanthroline (5,6-dmp), 4,7-dimethyl-1,10-phenanthroline (4,7-dmp), 2,9-dimethyl-1,10-phenanthroline (2,9-dmp), 3,4,7,8-tetra-methyl-1,10-phenanthroline (Me4phen), with calf thymus DNA has been studied using absorption, emission and circular dichroic spectral measurements and viscometry and electrochemical techniques. On interaction with DNA the complexes show hypochromism and red-shift in their MLCT band suggesting that the complexes bind to DNA. The magnitude of the binding constant (Kb) obtained from absorption spectral titration varies depending upon the nature of the diimine ligand: Me4phen > 5,6-dmp > 4,7-dmp > phen suggesting the use of diimine ‘face’ of the octahedral complexes in binding to DNA. The interaction of phen complex possibly involves phen ring partially inserted into the DNA base pairs. In contrast, the methyl-substituted phen complexes would involve hydrophobic interaction of the phen ring in the grooves of DNA, which is supported by hydrogen bonding interactions of the ammonia ligands with the intrastrand nucleobases. Also the shape and size of the phen ligand as modified by the methyl substituents determine the DNA binding site sizes (0.12-0.45 base pairs). The relative emission intensities (I/I0) of the DNA-bound complexes parallel the variation in Kb values. Almost all the metal complexes exhibit induced CD bands on binding to B DNA, with the 4,7-dmp and Me4phen complexes inducing certain structural modifications on the biopolymer. DNA melting curves obtained in the presence of metal complexes reveal a monophasic melting of the DNA strands, the Me4phen complex exhibiting a slightly enhanced tendency to stabilize the double-stranded DNA. There were slight to appreciable changes in the relative viscosities of DNA, which are consistent with enhanced hydrophobic interaction of the methyl-substituted phen rings. Upon interaction with CT DNA, the Me4phen, 4,7-dmp and 5,6-dmp complexes, in contrast to bipy, phen and 2,9-dmp complexes, show a decrease in anodic peak current in their cyclic voltammograms suggesting that they exhibit enhanced DNA binding. DNA cleavage experiments show that all the complexes induce cleavage of pBR322 plasmid DNA, the Me4phen and 5,6-dmp complexes being remarkably more efficient than other complexes. 相似文献
159.
Prasanth Rayorath Wajahatullah Khan Ravishankar Palanisamy Shawna L. MacKinnon Roumiana Stefanova Simon D. Hankins Alan T. Critchley Balakrishan Prithiviraj 《Journal of Plant Growth Regulation》2008,27(4):370-379
Extracts of the brown seaweed Ascophyllum nodosum have been used as a biostimulant to promote growth and productivity in a number of agricultural production systems. Although
the extracts have been shown to improve seedling emergence and vigor in a variety of plants, including barley, the mechanism(s)
of this growth-promoting effect is(are) largely unknown. In our study, A. nodosum extract induced amylase activity in barley seed-halves; a significant difference in amylase activity was observed in seeds
without an embryo. The addition of activated charcoal to the treatment media negated the bioactivity of the extracts suggesting
the organic nature of bioactive compounds in A. nodosum extracts. The extracts induced amylase activity in a gibberellic acid (GA)-deficient barley mutant (grd2). LC-MS-MS analysis failed to detect the presence of GA3 in the extracts. ABA supplementation of the medium caused a significant reduction of amylase activity in GA-treated seeds
compared with those treated with the A. nodosum extract. Taken together, our results suggest that the organic components of A. nodosum extract induce amylase activity independent of GA3 and might act in concert with GA-dependent amylase production leading to enhanced germination and seedling vigor in barley.
Being derived from a renewable resource, the bioactive compounds from A. nodosum could be used to improve crop productivity in sustainable agricultural systems. 相似文献
160.
Chronic restraint stress causes spatial learning and memory deficits, dendritic atrophy of the hippocampal pyramidal neurons
and alterations in the levels of neurotransmitters in the hippocampus. In contrast, intracranial self-stimulation (ICSS) rewarding
behavioral experience is known to increase dendritic arborization, spine and synaptic density, and increase neurotransmitter
levels in the hippocampus. In addition, ICSS facilitates operant and spatial learning, and ameliorates fornix-lesion induced
behavioral deficits. Although the effects of stress and ICSS are documented, it is not known whether ICSS following stress
would ameliorate the stress-induced deficits. Accordingly, the present study was aimed to evaluate the role of ICSS on stress-induced
changes in hippocampal morphology, neurochemistry, and behavioral performance in the T-maze. Experiments were conducted on
adult male Wistar rats, which were randomly divided into four groups; normal control, stress (ST), self-stimulation (SS),
and stress + self-stimulation (ST + SS). Stress group of rats were subjected to restraint stress for 6 h daily over 21 days,
SS group animals were subjected to SS from ventral tegmental area for 10 days and ST + SS rats were subjected to restraint
stress for 21 days followed by 10 days of SS. Interestingly, our results show that stress-induced behavioral deficits, dendritic
atrophy, and decreased levels of neurotransmitters were completely reversed following 10 days of SS experience. We propose
that SS rewarding behavioral experience ameliorates the stress-induced cognitive deficits by inducing structural and biochemical
changes in the hippocampus. 相似文献