Tough and stretchable ionogels by in situ phase separation.

Ionogels are compelling materials for technological devices due to their excellent ionic conductivity, thermal and electrochemical stability, and non-volatility. However, most existing ionogels suffer from low strength and toughness. Here, we report a simple one-step method to achieve ultra-tough and stretchable ionogels by randomly copolymerizing two common monomers with distinct solubility of the corresponding polymers in an ionic liquid. Copolymerization of acrylamide and acrylic acid in 1-ethyl-3-methylimidazolium ethyl sulfate results in a macroscopically homogeneous covalent network with in situ phase separation: a polymer-rich phase with hydrogen bonds that dissipate energy and toughen the ionogel; and an elastic solvent-rich phase that enables for large strain. These ionogels have high fracture strength (12.6 MPa), fracture energy (~24 kJ m-2) and Young's modulus (46.5 MPa), while being highly stretchable (~600% strain) and having self-healing and shape-memory properties. This concept can be applied to other monomers and ionic liquids, offering a promising way to tune ionogel microstructure and properties in situ during one-step polymerization.

Cuticular lipids and associated gene expression analysis under NaCl stress in Thellungiella salsuginea.

Cuticular lipids, including wax and cutin, protect plants against external environmental stress. The relationship between the cuticle properties and salt tolerance is not clear. In this article, photosynthetic and physiological characteristics related to water use and cuticle permeability were assessed in the leaves of Thellungiella salsuginea under NaCl stress. The chemical composition of wax and cutin monomers, and the expression of cuticle-associated genes were also analyzed. The results showed that the net photosynthetic rate and stomatal conductance in the leaves of T. salsuginea decreased, and the water use efficiency increased with increasing NaCl concentration. Salt stress caused a significant increase in total wax, but total cutin monomers only increased under high salt. Transcriptome sequencing and lipid metabolism pathway analysis were performed on rosette leaves of T. salsuginea after 24 h of NaCl treatment. We analyzed the expression of 42 genes involved in cuticle lipid metabolism, and found that most of them exhibited higher expression levels at 0.15 mol L-1 NaCl, but lower expression levels at 0.3 mol L-1 NaCl. The expression of 12 of these genes was further detected by qRT-PCR after 1 week of NaCl treatment: most of them were upregulated both under low and high NaCl stress. Hence, we speculate that the cuticle acts as an adaptive trait in T. salsuginea in salty environments.

Characterization of cesium uptake mediated by a potassium transport system of bacteria in a soil conditioner.

We found that bacteria in a commercial soil conditioner sold in Ishinomaki, Miyagi, exhibited concentrative and saturable cesium ion (Cs(+)) uptake in the natural range of pH and temperature. The concentration of intracellular Cs(+) could be condensed at least a few times higher compared with the outside medium of the cells. This uptake appeared to be mediated by a K(+) transport system, since Cs(+) uptake was dose-dependently inhibited by potassium ion (K(+)). Eadie-Hofstee plot analysis indicated that the Cs(+) uptake involved a single saturable process. The maximum uptake amount (Jmax) was the same in the presence and absence of K(+), suggesting that Cs(+) and K(+) uptakes were competitive with respect to each other. These bacteria might be useful for bioremediation of cesium-contaminated soil.

Six new cadinane-type sesquiterpenoids from the leaves of Chimonanthus nitens Oliv.

Six new cadinane-type sesquiterpenoids, named Chimnitensin A-F (1-6) were isolated from the leaves of Chimonanthus nitens Oliv. Their structures were elucidated by comprehensive spectroscopic analyses and comparison with structurally related known analogues. In vitro MTT assay showed that all six compounds had cytotoxicity against two selected human breast cancer cell lines (MDA-MB-468 and MDA-MB-231), which indicate their potential of developing into anticancer drugs.

Unique Flexible NiFe2O4@S/rGO-CNT Electrode via the Synergistic Adsorption/Electrocatalysis Effect toward High-Performance Lithium-Sulfur Batteries.

A unique flexible NiFe2O4 hollow sphere@S/rGO-CNT (NiFe2O4@S/C) cathode was rationally designed and synthesized to tackle the issues of lithium-sulfur batteries. In this strategy, the introduced rGO and CNTs offer a flexible and conductive skeleton to facilitate the transport of electrons and/or ions and a physical barrier to confine polysulfides. Furthermore, as an efficient sulfur host, NiFe2O4 hollow spheres can further absorb the soluble polysulfides by strong chemical interaction due to their intrinsic polarity and also serve as a catalyst to promote the redox kinetics of polysulfide conversion. Benefiting from the synergism of the physical confinement, polar chemical adsorption, and catalytic conversion, the as-prepared flexible NiFe2O4@S/C electrode delivers a high initial capacity of 1193 mAh g-1 at 100 mA g-1 and excellent long-term cycling stability up to 500 cycles with a low decay rate of 0.059% per cycle at 500 mA g-1.

Characterization of the cheetah serum amyloid A1 gene: critical role and functional polymorphism of a cis-acting element.

Amyloid A (AA) amyloidosis is one of the principal causes of morbidity and mortality in captive cheetahs (Acinonyx jubatus), which are in danger of extinction. For practical conservation of this species, therefore, it is critical to elucidate the etiology of AA amyloidosis, especially to understand the mechanisms of transcriptional regulation of serum amyloid A (SAA), a precursor protein of the AA protein. In this study, the structure and nucleotide sequence of the cheetah SAA1 gene including the 5'-flanking promoter/enhancer region was determined. Putative nuclear factor kappa-B (NF-kappaB) and CCAAT/enhancer binding protein beta (C/EBPbeta) cis-acting elements, which play key roles in SAA1 transcriptional induction in response to inflammation, were identified in the 5'-flanking region of the cheetah SAA1 gene. Fortuitously, a single nucleotide polymorphism was identified in the captive cheetah cohort in the putative NF-kappaB cis-acting element and had a remarkable effect on SAA1 transcriptional induction. These results provide a foundation not only for clarifying the etiology of AA amyloidosis in the cheetah but also for contriving a strategy for conservation of this species.

Mouse model to study human A beta2M amyloidosis: generation of a transgenic mouse with excessive expression of human beta2-microglobulin.

Patients on long-term hemodialysis can develop dialysis-related amyloidosis (DRA) due to deposition of beta(2)-microglobulin (beta(2)m) into amyloid fibrils (Abeta(2)M). Despite intensive biochemical studies, the pathogenesis of amyloid deposition in DRA patients remains poorly understood. To elucidate the mechanisms that underlie Abeta(2)M fibril formation in DRA, we generated transgenic mice that overexpress human beta(2)m protein in a mouse beta(2)m gene knockout background (hB2MTg(+/+) mB2m(+/+)). The hB2MTg(+/+)mB2m(-/-) mice express a high level of human beta(2)m protein in many tissues as well as a high plasma beta(2)m concentration (192.8 mg/L). This concentration is >100 times higher than that observed in healthy humans and >4 times higher than that detected in patients on dialysis. We examined spontaneous and amyloid fibril-induced amyloid deposition in these mice. Amyloid deposition of beta(2)m protein was not observed in aged or amyloid fibril injected animals. However, mouse senile apolipoprotein A-II amyloidosis (AApoAII) was detected, particularly in the joints of mice that were injected with AApoAII amyloid fibrils. This study demonstrates that this mouse model could be valuable in studying the components and conditions that promote DRA, and indicates that high plasma concentrations of hbeta(2)m as well as seeding with pre-existing amyloid fibrils may not be sufficient to induce Abeta(2)M.

Slaughtered aged cattle might be one dietary source exhibiting amyloid enhancing factor activity.

It has been shown that experimental murine AA amyloidosis can be enhanced by dietary ingestion of amyloid fibrils, and it is known that systemic AA amyloidosis occasionally develops in aged cattle. In this study, we examined amyloid deposits in renal and muscular tissues simultaneously obtained from slaughtered aged cattle; from both tissues when affected, amyloid-enhancing activity was also investigated. On histopathology, renal amyloid deposition was seen in nine of the 293 cattle with no history of disease, and minute amyloid deposition in muscular tissue was detectable in one of these nine. All these amyloid deposits were immunohistochemically demonstrated to be AA. Extracts, which might contain amyloid fibril fractions, were isolated from renal and muscular tissues in five of these nine cattle. On SDS-PAGE and Western blot analysis, protein bands immunoreactive to anti-AA serum were detected in the kidney fractions obtained from four of the five latter cattle, but no bands were seen in the muscle fractions of any of the five cattle. Amyloid fibril fractions from two cattle were intravenously injected into group of seven experimentally designed mice for induction of AA amyloidosis. All seven mice injected with kidney fraction developed severe AA amyloidosis, whereas only one of the seven mice given muscle fraction showed slight amyloid deposition in the spleen. These data suggest that food products made from aged cattle possess amyloid-enhancing potential.