3,190 research outputs found
Bis(μ-5-carboxybenzene-1,3-dicarboxylato)-κ3 O 1,O 1′:O 3;κ3 O 3:O 1,O 1′-bis[(2-phenyl-1,3,7,8-tetraazacyclopenta[l]phenanthrene-κ2 N 7,N 8)lead(II)]
In the title compound, [Pb2(C9H4O6)2(C19H12N4)2], the PbII atom is five-coordinated by two N atoms from a chelating 2-phenyl-1H-1,3,7,8-tetraazacyclopenta[l]phenanthrene (L) ligand and three O atoms from two Hbtc ligands (H3btc is benzene-1,3,5-tricarboxylic acid), resulting in a distorted PbN2O3 coordination. Two PbII atoms are bridged by the Hbtc ligands, forming a discrete centrosymmetric dinuclear complex. Intermolecular N—H⋯O and O—H⋯O hydrogen bonds and π–π interactions between the pyridine and imidazole rings, and between the pyridyl rings of the L ligands [centroid–centroid distances = 3.600 (6) and 3.732 (6) Å] lead to a three-dimensional supramolecular structure
2-Phenyl-1H-1,3,7,8-tetraazacyclopenta[l]phenanthrene
There are two molecules in the asymmetric unit of the title compound, C19H12N4, with dihedral angles of 2.41 (10) and 10.53 (12)° between the fused ring system and the pendant phenyl ring. In the crystal, molecules are linked into chains by N—H⋯N hydrogen bonds and aromatic π–π stacking interactions [shortest centroid–centroid distance = 3.6176 (16) Å] complete the structure
Associations between Aquaglyceroporin Gene Polymorphisms and Risk of Stroke among Patients with Hypertension
Background: Dysregulations ofAQP7andAQP9were found to be related to lipid metabolism abnormality, which had been provento be one of the mechanisms of stroke. However, limited epidemiological studies explore the associations betweenAQP7andAQP9and the risk of stroke among patients with hypertension in China.
Aims: We aimed to investigate the associations between genetic variants in AQP7andAQP9and the risk of stroke among patients with hypertension, as well as to explore gene-gene andgene-environment interactions.
Methods: Baseline blood samples were drawn from 211 cases with stroke and 633 matched controls. Genomic DNA was extracted by a commercially available kit. Genotyping of 5 single nucleotide polymorphisms (SNPs) in AQP7 (rs2989924, rs3758269, and rs2542743) and AQP9 (rs57139208, rs16939881) was performed by the polymerase chain reaction assay with TaqMan probes.
Results: Participants with the rs2989924 GG genotype were found to be with a 1.74-fold increased risk of stroke compared to those with the AA+AG genotype, and this association remained significant after adjustment for potential confounders (odds ratio (OR): 1.74, 95% confidence interval (CI): 1.23-2.46). The SNP rs3758269 CC+TT genotype was found to be with a 33% decreased risk of stroke after multivariate adjustment (OR: 0.67, 95% CI: 0.45-0.99) compared to the rs3758269 CC genotype. The significantly increased risk of stroke was prominent among males, patients aged 60 or above, and participants who were overweight and with a harbored genetic variant in SNP rs2989924. After adjusting potential confounders, the SNP rs3758269 CT+TT genotype was found to be significantly associated with a decreased risk of stroke compared to the CC genotype among participants younger than 60 years old or overweight. No statistically significant associations were observed between genotypes of rs2542743, rs57139208, or rs16939881 with the risk of stroke. Neither interactions nor linkage disequilibrium had been observed in this study.
Conclusions: This study suggests that SNPs rs2989924 and rs3758269 are associated with the risk of stroke among patients with hypertension, while there were no statistically significant associations between rs2542743, rs57139208, and rs16939881 and the risk of stroke being observed
Unconventional Superconducting Symmetry in a Checkerboard Antiferromagnet
We use a renormalized mean field theory to study the Gutzwiller projected BCS
states of the extended Hubbard model in the large limit, or the
--- model on a two-dimensional checkerboard lattice. At small
, the frustration due to the diagonal terms of and does not
alter the -wave pairing symmetry, and the negative (positive)
enhances (suppresses) the pairing order parameter. At large , the
ground state has an extended s-wave symmetry. At the intermediate , the
ground state is or -wave with time reversal symmetry broken.Comment: 6 pages, 6 figure
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