(4S,5S)-2-(3-Methoxy­phen­yl)-1,3-dioxolane-4,5-dicarboxamide

In the title compound, C12H14N2O5, the five-membered ring adopts an envelope conformation. In the crystal structure, inter­molecular N—H⋯O inter­actions link the mol­ecules into a three-dimensional network. A weak C—H⋯π inter­action is also found

catena-Poly[[diaqua­[(4-tolyl­sulfan­yl)acetato-κO]cadmium(II)]-μ-4,4′-bipyridine-κ2 N:N′]

The title complex, [Cd(C9H9O2S)2(C10H8N2)(H2O)2]n, has a linear chain structure. The central CdII ion is in a slightly disorted octa­hedral environment, coordinated by two aqua ligands, two (4-tolyl­sulfan­yl)acetate ligands and two bridging 4,4′-bipyridine ligands. The CdII ion lies on a twofold rotation axis. Inter­molecular O—H⋯O hydrogen bonds connect adjacent chains, forming a layer structure. An intramolecular O—H⋯O hydrogen bond is also present

trans-4-(Tosyl­oxymeth­yl)cyclo­hexane­carboxylic acid

The title compound, C15H20O5S, is an inter­mediate in the synthesis of a new type of poly(amido­amine) (PAMAM) dendrimer. The cyclo­hexane ring exhibits a chair conformation, with C—C bond lengths in the range 1.518 (3)–1.531 (3) Å and C—C—C angles in the range 110.45 (19)–112.09 (19)°; these agree well with the values in other cyclo­hexane derivatives described in the literature. In the crystal structure, adjacent mol­ecules are linked by O—H⋯·O hydrogen bonds. The H atoms of the methyl group are disordered equally over two positions

(E)-N′-(5-Chloro-2-hydroxy­benzyl­idene)-4-(8-quinol­yloxy)butanohydrazide monohydrate

The crystal of the title Schiff base compound, C20H18ClN3O3·H2O, was twinned by a twofold rotation about (100). The asymmetric unit contains two crystallographically independent mol­ecules with similar conformations, and two water mol­ecules. The C=N—N angles of 115.7 (6) and 116.2 (6)° are significantly smaller than the ideal value of 120° expected for sp 2-hybridized N atoms and the dihedral angles between the benzene ring and quinoline ring system in the two mol­ecules are 52.5 (7) and 53.9 (7)°. The mol­ecules aggregate via C—Cl⋯π and π–π inter­actions [centroid–centroid distances = 3.696 (5)–3.892 (5) Å] and weak C—H⋯O inter­actions as parallel sheets, which are further linked by water mol­ecules through N—H⋯O and O—H⋯O hydrogen bonds into a supra­molecular two-dimensional network

trans-4-(Phenoxy­meth­yl)cyclo­hexane­carboxylic acid

The title compound, C14H18O3, is an important model compound in the synthesis of phenolic ethers. The cyclo­hexane ring adopts a chair conformation. In the crystal structure, adjacent mol­ecules are linked by O—H⋯O hydrogen bonds

Strain Induced One-Dimensional Landau-Level Quantization in Corrugated Graphene

Theoretical research has predicted that ripples of graphene generates effective gauge field on its low energy electronic structure and could lead to zero-energy flat bands, which are the analog of Landau levels in real magnetic fields. Here we demonstrate, using a combination of scanning tunneling microscopy and tight-binding approximation, that the zero-energy Landau levels with vanishing Fermi velocities will form when the effective pseudomagnetic flux per ripple is larger than the flux quantum. Our analysis indicates that the effective gauge field of the ripples results in zero-energy flat bands in one direction but not in another. The Fermi velocities in the perpendicular direction of the ripples are not renormalized at all. The condition to generate the ripples is also discussed according to classical thin-film elasticity theory.Comment: 4 figures, Phys. Rev.

Genetic polymorphism in the manganese superoxide dismutase gene, antioxidant intake, and breast cancer risk: results from the Shanghai Breast Cancer Study

INTRODUCTION: It has been suggested that oxidative stress and mitochondrial DNA damage play important roles in breast cancer carcinogenesis. Manganese superoxide dismutase (MnSOD) is a major enzyme that is responsible for the detoxification of reactive oxygen species in the mitochondria. A T → C substitution in the MnSOD gene results in a Val → Ala change at the -9 position of the mitochondrial targeting sequence (Val-9Ala), which alters the protein secondary structure and thus affects transport of MnSOD into the mitochondria. METHODS: We evaluated this genetic polymorphism in association with breast cancer risk using data from the Shanghai Breast Cancer Study, a population-based case–control study conducted in urban Shanghai from 1996 to 1998. The MnSOD Val-9Ala polymorphism was examined in 1125 breast cancer cases and 1197 age-frequency-matched control individual. RESULTS: Breast cancer risk was slightly elevated in women with Ala/Ala genotype (odds ratio [OR] 1.3, 95% confidence interval [CI] 0.7–2.3), particularly among premenopausal women (OR 1.8, 95% CI 0.9–3.7), as compared with those with Val/Val genotype. The increased risk with the Ala/Ala genotype was stronger among premenopausal women with a higher body mass index (OR 2.5, 95% CI 0.9–7.0) and more years of menstruation (OR 2.6, 95% CI 0.8–8.0). The risk among premenopausal women was further increased twofold to threefold among those with a low intake of fruits, vegetables, vitamin supplements, selenium, or antioxidant vitamins, including carotenes and vitamins A, C, and E. However, the frequency of the Ala allele was low (14%) in the study population, and most of the ORs provided above were not statistically significant. CONCLUSION: The present study provides some evidence that genetic polymorphism in the MnSOD gene may be associated with increased risk of breast cancer among Chinese women with high levels of oxidative stress or low intake of antioxidants. Studies with a larger sample size are needed to confirm the findings

Decrease in CD4+CD25+FoxP3+ Treg cells after pulmonary resection in the treatment of cavity multidrug-resistant tuberculosis

SummaryObjectivesImmune regulatory mechanisms may limit the immunopathologic condition of infection with Mycobacterium tuberculosis and suppress cellular immune responses in the host. We investigated the CD4+CD25+FoxP3+ circulating regulatory T cells (Treg) in patients with cavity multidrug-resistant tuberculosis (MDR-TB) before and after surgery.MethodsWe compared the proportion of Treg cells in 13 patients with cavity MDR-TB pre- and postoperatively and in 10 healthy control subjects by flow cytometry using three specific markers in peripheral blood lymphocytes: cell-surface CD4 and CD25 expression and intracellular FoxP3 expression.ResultsThe proportion of CD4+CD25high and CD4+CD25+FoxP3+ Treg was significantly higher in patients with cavity MDR-TB and at 1-month postoperatively than in healthy controls (p<0.001). The proportion of CD4+ and CD4+CD25− cells was significantly lower in patients with cavity MDR-TB than in controls (p<0.001). Pre- and postoperative proportions of CD4+CD25high and CD4+CD25+FoxP3+ Treg cells showed a positive correlation (r=0.878, p<0.001).ConclusionCirculating Treg cells are increased in proportion in patients with cavity MDR-TB and decreased after surgery. Infection with M. tuberculosis may induce Treg cell-surface molecular changes with increased numbers of cells