Phase Transition for Zinc Sulfide Nanosheets under High Pressure

This study describes the pressure-induced behavior of ZnS nanosheets by synchrotron angle-dispersive X-ray diffraction (ADXD) measurement up to 32.7 GPa. ZnS nanosheets transform from zinc blende structure to rock salt phase at 13.1 GPa and subsequently to a <i>Cmcm</i> structure at 20.3 GPa. The transition to the <i>Cmcm</i> structure is irreversible for ZnS nanomaterials at a much lower critical pressure than required for ZnS bulk materials. The special morphology of ZnS nanosheets plays a crucial role in the transition to <i>Cmcm</i> structures at comparatively low pressure. Continuous changes in lattice volume in the absence of volume collapse are observed after the transition from rock salt to the <i>Cmcm</i> structure occurs

Degradation of atrazine by strain HB-6 at different culture conditions.

<p>Different pH values (a), temperatures (b) and initial concentration of atrazine (c). Error bars represent the standard deviation of three replicates.</p

Phylogenetic tree based on the 16S rDNA sequence data.

<p>Numbers at the nodes indicate bootstrap values from the neighborhood-joining analysis of 1,000 resampled data sets. The bar indicates 0.005 substitution per nucleotide position.</p

Proposed pathway for degradation of atrazine by strain HB-6.

<p>Proposed pathway for degradation of atrazine by strain HB-6.</p

Atrazine-degrading gene amplification of HB-6.

<p>Lane 1: DNA marker, lane 2: <i>trzN</i> of HB-6, lane 3: <i>atzB</i> of HB-6, lane 4: <i>atzC</i> of HB-6.</p

HPLC of extracts from cell supernatants after metabolism of atrazine by HB-6 or HB-6+HB-5.

<p>Degradation by HB-6 (a), degradation by HB-6 together with HB-5 (b). Error bars represent the standard deviation of three replicates.</p

HPLC-MS identification of the metabolites produced from atrazine by HB-6.

<p>Hydroxyatrazine (a), cyanuric acid (b) and urea (c).</p

Amelioration of cognitive impairments in APPswe/PS1dE9 mice is associated with metabolites alteration induced by total salvianolic acid

<div><p>Purpose</p><p>Total salvianolic acid (TSA) is extracted from salvia miltiorrhiza; however, to date, there has been limited characterization of its effects on metabolites in Alzheimer’s disease model-APPswe/PS1dE9 mice. The main objective of this study was to investigate the metabolic changes in 7-month-old APPswe/PS1dE9 mice treated with TSA, which protects against learning and memory impairment.</p><p>Methods</p><p>APPswe/PS1dE9 mice were treated with TSA (30 mg/kg·d and 60 mg/kg·d, i.p.) and saline (i.p.) daily from 3.5 months old for 14 weeks; saline-treated (i.p.) WT mice were included as the controls. The effects of TSA on learning and memory were assessed by a series of behavioral tests, including the NOR, MWM and step-through tasks. The FBG and plasma lipid levels were subsequently assessed using the GOPOD and enzymatic color methods, respectively. Finally, the concentrations of Aβ42, Aβ40 and metabolites in the hippocampus of the mice were detected via ELISA and GC-TOF-MS, respectively.</p><p>Results</p><p>At 7 months of age, the APPswe/PS1dE9 mice treated with TSA exhibited an improvement in the preference index (PI) one hour after the acquisition phase in the NOR and the preservation of spatial learning and memory in the MWM. Treatment with TSA substantially decreased the LDL-C level, and 60 mg/kg TSA decreased the CHOL level compared with the plasma level of the APPswe/PS1dE9 group. The Aβ42 and Aβ40 levels in the hippocampus were decreased in the TSA-treated group compared with the saline-treated APPswe/PS1dE9 group. The regulation of metabolic pathways relevant to TSA predominantly included carbohydrate metabolism, such as sorbitol, glucose-6-phosphate, sucrose-6-phosphate and galactose, vitamin metabolism involved in cholecalciferol and ascorbate in the hippocampus.</p><p>Conclusions</p><p>TSA induced a remarkable amelioration of learning and memory impairments in APPswe/PS1dE9 mice through the regulation of Aβ42, Aβ40, carbohydrate and vitamin metabolites in the hippocampus and LDL-C and CHOL in the plasma.</p></div

A new cyclopeptide with antifungal activity from the co-culture broth of two marine mangrove fungi

<div><p>A new cyclic tetrapeptide, cyclo-(l-leucyl-<i>trans</i>-4-hydroxy-l-prolyl-d-leucyl-<i>trans</i>-4-hydroxy-l-proline) (<b>1</b>), was isolated from the co-culture broth of two mangrove fungi <i>Phomopsis</i> sp. K38 and <i>Alternaria</i> sp. E33. The structure of <b>1</b> was determined by analysis of spectroscopic data and Marfey's analytic method. Primary bioassay demonstrated that compound <b>1</b> exhibited moderate to high inhibitory activity against four crop-threatening fungi including <i>Gaeumannomyces graminis</i>, <i>Rhizoctonia cerealis</i>, <i>Helminthosporium sativum</i> and <i>Fusarium graminearum</i> as compared with triadimefon.</p></div

Comparison of retention latency 24 hours after foot shock.

<p>There was no significant difference among the WT control, APPswe/PS1dE9 transgenic, or 30 mg/kg or 60 mg/kg TSA-treated groups. Data are presented as the mean±SEM, <i>n</i> = 20.</p