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Bacteria-inspired magnetic helical micro-/nanoswimmers can be actuated and steered in a fuel-free manner using a low-strength rotating magnetic field, generating remotely controlled 3D locomotion with high precision in a variety of biofluidic environments. They are therefore envisioned for biomedical applications related to targeted diagnosis and therapy. In this article, a porous hollow microswimmer possessing an outer shell aggregated by mesoporous spindle-like magnetite nanoparticles (NPs) and a helical-shaped inner cavity is proposed. The fabrication is straightforward via a cost-effective mass-production process of biotemplated synthesis using helical microorganisms. Here, Spirulina-based fabrication is demonstrated as an example. The fabricated microswimmers are superparamagnetic and exhibit low cytotoxicity. They are also capable of performing structural disassembly to form individual NPs using ultrasound when needed. For the first time in the literature of helical microswimmers, a porous hollow architecture is successfully constructed, achieving an ultrahigh specific surface area for surface functionalization and enabling diffusion-based cargo loading/release. Furthermore, experimental and analytical results indicate better swimming performance of the microswimmers than the existing non-hollow helical micromachines of comparable sizes and dimensions. These characteristics of the as-proposed microswimmers suggest a novel microrobotic tool with high loading capacity for targeted delivery of therapeutic/imaging agents in vitro and in vivo. [ABSTRACT FROM AUTHOR]

3D hollow‐carbon‐spheres/graphene‐flake hybrid nanostructures are controllably prepared from a polypropylene/montmorillonite/Fe3O4 composite by a self‐assembly and subsequent carbonization process. More importantly, in the resultant hollow‐carbon‐spheres/graphene‐flake hybrid structures, the monodispersed small hollow carbon spheres can be distributed on the graphene flake with controllable density. The obtained hollow‐carbon‐spheres/graphene‐flake hybrid nanostructures show improved performance in lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

The dysfunction of endothelial progenitor cells (EPCs) limits their potential for the treatment of ischemia and atherosclerosis. Therefore, we investigated the effect of tripterine on EPC function and examined the underlying mechanisms. The effect of tripterine, an active component of Tripterygium wilfordii Hook, on the enhancement of EPC function and the efficiency of EPC transplantation was investigated in vitro and in vivo. Treatment of EPCs with tripterine at 2.5 µM for 4 h inhibited oxidized low-density lipoprotein (ox-LDL) induced ROS production, cell apoptosis, and cell senescence and improved the migration and tube formation capacities of EPCs treated with ox-LDL (200 µg/ml). In vivo studies showed that tripterine conditioning of EPCs administered to ischemic foci improved blood perfusion and microvascular density in a mouse hindlimb ischemia model. Examination of the underlying mechanisms indicated that the effect of tripterine is mediated by the induction of heat shock protein 32 expression and the inhibition of JNK activation. The present results are of clinical significance because they suggest the potential of tripterine as a therapeutic agent to improve the efficacy of EPC transplantation for the treatment of ischemic diseases. J. Cell. Physiol. 230: 1139-1147, 2015. © 2014 Wiley Periodicals, Inc., A Wiley Company [ABSTRACT FROM AUTHOR]

Damage of blood-brain barrier is a common result of traumatic brain injury. This damage can open the blood-brain barrier and allow drug passage. An ultraperformance liquid chromatography with tandem mass spectrometry method was established to determine the concentration of rhein in the biofluids (plasma and cerebrospinal fluid) of patients with a compromised blood-brain barrier following traumatic brain injury after rhubarb administration. Furthermore, the pharmacokinetic profiles were analyzed. A triple-quadruple tandem mass spectrometer with electrospray ionization was used for rhein detection. The mass transition followed was m/z 283.06→239.0. The calibration curve was linear in the concentration range of 10-8000 ng/mL for the biofluids. The intra- and interday precisions were less than 10%. The relative standard deviation of recovery was less than 15% in biological matrices. The pharmacokinetic data showed that rhein was rapidly transported into biofluids, and exhibited a peak concentration 1 h after rhubarb administration. The elimination rate of rhein was slow. The AUCcerebrospinal fluid/AUCplasma (AUC is area under curve) of rhein was approximately 17%, indicating that portions of rhein could pass the impaired blood-brain barrier. The method was successfully applied to quantify rhein in the biofluids of all patients. The data presented can help to guide clinical applications of rhubarb for treating traumatic brain injury. [ABSTRACT FROM AUTHOR]

Hydrozirconation on vinyl-terminated substrates (silicon wafer and nanosilica sphere) is employed as an efficient way for immobilization of zirconocene catalyst through ZrC bonds, which is applied in surface coordination ethylene polymerization producing surface-tethered polyethylene (PE). The formation of ZrC σ bond induced by hydrozirconation provides an initiator precursor for growing a layer of PE covalently linked onto substrates. The results from SEM, AFM, and TEM show that the surface polymerization is controlled by hydrozirconation. Surface pattern or core-shell structure with crystalline PE coating can be formed, when silicon wafer is selectively functionalized with vinyl-groups or vinyl-modified nanosilica is applied. It is believed that hydrozirconation for the synthesis of zirconocene initiator can be a versatile route to prepare polyolefin hybrid materials. [ABSTRACT FROM AUTHOR]

Core-shell-structured mesoporous silica spheres were prepared by using n-octadecyltrimethoxysilane (C18TMS) as the surfactant. Hollow mesoporous carbon spheres with controllable diameters were fabricated from core-shell-structured mesoporous silica sphere templates by (CVD). By controlling the thickness of the silica shell, hollow carbon spheres (HCSs) with different diameters can be obtained. The use of ethylene as the carbon precursor in the produces the materials in a single step without the need to remove the surfactant. The mechanism of formation and the role played by the surfactant, C18TMS, are investigated. The materials have large potential in double-layer supercapacitors, and their electrochemical properties were determined. HCSs with thicker mesoporous shells possess a larger surface area, which in turn increases their electrochemical capacitance. The samples prepared at a lower temperature also exhibit increased capacitance as a result of the Brunauer-Emmett-Teller (BET) area and larger pore size. [ABSTRACT FROM AUTHOR]

A series of graft (co)polymers were synthesized by nucleophilic substitution reaction between iodinated 1,2-polybutadiene (PB-I, backbone) and living polymer lithium (side chains). The coupling reaction between PB-I and living polymers can finish within minutes at room temperature, and high conversion (up to 92%) could be obtained by effectively avoiding side reaction of dimerization when living polymers were capped with 1,1-diphenylethylene. By virtue of living anionic polymerization, backbone length, side chain length, and side chain composition, as well as graft density, were well controlled. Tunable molecular weight of graft (co)polymers with narrow molecular weight distribution can be obtained by changing either the lengths of side chain and backbone, or the graft density. Graft copolymers could also be synthesized with side chains of multicomponent polymers, such as block polymer (polystyrene- b-polybutadiene) and even mixed polymers (polystyrene and polybutadiene) as hetero chains. Thus, based on living anionic polymerization, this work provides a facile way for modular synthesis of graft (co)polymers via nucleophilic substitution reaction between living polymers and polyhalohydrocarbon (PB-I). © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 [ABSTRACT FROM AUTHOR]

Azulene-containing conjugated polymers with near-infrared absorption up to 1.5 μm and beyond are achieved by treating with trifluoroacetic acid (TFA). Density functional theory calculations reveal that the near-infrared absorption arises from a strong intramolecular charge transfer transition on the polymer backbone, and the near-infrared absorption can be tuned by the degree of protonation. Furthermore, TFA treated polymers show a ten-fold enhancement in electrochromic contrast and significantly improved switching stability, suggesting that these polymers are promising candidates for fabrication of the first generation organic near-infrared devices. [ABSTRACT FROM AUTHOR]

Controlled chain-scission of polybutadiene (PB), polyisoprene, and poly(styrene-co-butadiene), induced by bis(cyclopentadienyl) zirconium hydrochloride (Cp2ZrHCl), was revealed at room temperature. The chain-scission reaction of linear PB was studied by means of GPC, NMR spectroscopy, and MALDI-TOF-MS. It was confirmed that the molecular weights of degraded products were quasi-quantitatively controlled by Cp2ZrHCl loading, irrespective of the starting PB, whereas the microstructure of PB chains was crucial to the scission reaction. The hydrozirconation of model molecules indicated that the existence of an internal double bond in compounds with multiple double bonds was essential for chain cleavage. The chain-cleavage mechanism was proposed to involve hydrozirconation of internal double bonds in PB chains and β-alkyl elimination. Furthermore, metallocene-catalyzed chain-scission by a chain-transfer reaction was developed. It is believed that the reported chain scission offers a promising pathway for end-group functionalization by chain cleavage and presents a new application of Schwartz's reagent. [ABSTRACT FROM AUTHOR]

Eur J Clin Invest 2012; 42 (7): 751-759 Abstract Background Colorectal cancer is one of the most rapidly increasing cancers in the world, and accumulation of alterations in oncogenes, tumour suppressor genes and mismatch repair (MMR) genes contributes to colorectal tumorigenesis. Thus, we investigated the alterations of 14 microsatellite loci adjacent to MMR genes, p53, adenomatous polyposis coli (APC) and K-ras in 52 Chinese patients with colorectal cancer. Materials and Methods We performed fluorescent polymerase chain reaction and capillary electrophoresis to analyse microsatellite instability (MSI) and loss of heterozygosity (LOH) in microsatellite loci, which included a panel of nine dinucleotide repeats and the Bethesda consensus panel. Additionally, we screened for mutations in exons 4-9 of p53 and the mutation cluster region (MCR) in APC by DHPLC. Codons 12, 13 and 61 in K-ras were analysed using direct sequencing. All variations were confirmed using clone sequencing. Results The alteration frequency of microsatellite DNA was 55·8% (29/52). Among the microsatellites, five loci exhibited MSI and another nine loci exhibited LOH. The mutation rates of p53, APC and K-ras were 42·3%, 38·5% and 36·5%, respectively. All patients ( n = 7) with liver metastasis had a mutation in p53, APC or K-ras. APC mutation was correlated with clinical stage and the presence of lymph node metastasis ( P = 0·001 and P = 0·006, respectively). Conclusions A total of 80·8% of Chinese patients with colorectal cancer show variations in microsatellite DNA, p53, APC or K-ras. It appears that these microsatellite DNA alterations could be a new biomarker for colorectal cancer. [ABSTRACT FROM AUTHOR]

Shape‐morphing structures are appealing in the material community to inspire a myriad of applications across domains, including soft robots, tissue engineering, and consumer products. However, it is a challenge to create fast response/recovery actuators with complicated and robust deformation due to the slow diffusion speed of water in hydrogel and small modulus of hydrogel. Herein, a facile strategy is proposed to fabricate a versatile patterned film configuration using chitin and poly(dimethylsiloxane) (PDMS). The direct‐ink writing (DIW) technique is leveraged to build simple, flat, patterned films, which can be morphed into complicated multidimensional architectures. Additionally, computational simulations are conducted to predict the deformation behaviors of the actuator. The sequential response structure can be precisely manipulated by the actuation speed of different structures. Moreover, an assembling method is proposed to create multifunction actuators. [ABSTRACT FROM AUTHOR]

Background: Traumatic brain injury (TBI) has increased in rank among traumatic injuries worldwide. Traumatic brain injury is a serious obstacle given that its complex pathology represents a long‐term process. Recently, systems biology strategies such as metabolomics to investigate the multifactorial nature of TBI have facilitated attempts to find biomarkers and probe molecular pathways for its diagnosis and therapy. Methods: This study included a group of 20 rats with controlled cortical impact and a group of 20 sham rats. We utilized mNSS tests to investigate neurological metabolic impairments on day 1 and day 3. Furthermore, we applied metabolomics and bioinformatics to determine the metabolic perturbation caused by TBI during the acute period in the hippocampus tissue of controlled cortical impact (CCI) rats. Notably, TBI–protein–metabolite subnetworks identified from a database were assessed for associations between metabolites and TBI by the dysregulation of related enzymes and transporters. Results: Our results identified 7 and 8 biomarkers on day 1 and day 3, respectively. Additionally, related pathway disorders showed effects on arginine and proline metabolism as well as taurine and hypotaurine metabolism on day 3 in acute TBI. Furthermore, according to metabolite–protein database searches, 25 metabolite–protein pairs were established as causally associated with TBI. Further, bioinformation indicated that these TBI‐associated proteins mainly take part in 5′‐nucleotidase activity and carboxylic acid transmembrane transport. In addition, interweaved networks were constructed to show that the development of TBI might be affected by metabolite‐related proteins and their protein pathways. Conclusion: The overall results show that acute TBI is susceptible to metabolic disorders, and the joint metabolite–protein network analysis provides a favorable prediction of TBI pathogenesis mechanisms in the brain. The signatures in the hippocampus might be promising for the development of biomarkers and pathways relevant to acute TBI and could further guide testable predictions of the underlying mechanism of TBI. [ABSTRACT FROM AUTHOR]

The mol­ecule of the title compound, C36H28N2, adopts a propeller-like shape and possesses crystallographically imposed twofold rotation symmetry. The N atom has an almost ideal trigonal geometry, indicating that the lone electron pair is involved in conjugation with the system of aromatic rings. [ABSTRACT FROM AUTHOR]

Highlights from the article: Selective Synthesis of Magnetite Nanospheres with Controllable Morphologies on CNTs and Application to Lithium-Ion Batteries (Phys. In this cover image, three kinds of nanostructures are described as hollow Fe SB 3 sb O SB 4 sb -CNT, mesopore Fe SB 3 sb O SB 4 sb -carbon nanotubes (CNT) and solid Fe SB 3 sb O SB 4 sb -CNT for lithium ion battery (from left to right). And the Fe SB 3 sb O SB 4 sb nanospheres are beaded with CNTs.

Iron oxide is widely used in many areas due to its environmental friendliness, low cost, as well as unique intrinsic properties and the morphology is one of the important parameters determining the physical properties. In this work, Fe3O4 nanospheres with different morphologies are synthesized on carbon nanotubes (CNTs) hydrothermally and by controlling the reaction conditions, solid, porous, and hollow Fe3O4 nanospheres are conjugated with CNTs selectively and the three different structures are investigated as anode materials in lithium‐ion batteries. The morphology of Fe3O4 is found to have a profound effect on the electrochemical performance of the lithium‐ion batteries under the same operating conditions. At high current densities, the hollow Fe3O4‐CNT delivers the best electrochemical performance but at low current densities, the solid Fe3O4‐CNT fares the best. The results provide insights into the design of high‐efficiency anode materials in lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Introduction: Intracerebral hemorrhage (ICH) is a lethal cerebrovascular disorder with a high mortality and morbidity. The pathophysiological mechanisms underlying ICH‐induced secondary injury remain unclear. Methods: To examine one of the gaps in the knowledge about ICH pathological mechanisms, isobaric tag for relative and absolute quantification (iTRAQ)‐based liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) was used in collagenase‐induced ICH rats on the 2nd day. Results: A total of 6,456 proteins were identified with a 1% false discovery rate (FDR). Of these proteins, 126 and 75 differentially expressed proteins (DEPs) were substantially increased and decreased, respectively. Based on Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and STRING analyses, the protein changes in cerebral hemorrhage were comprehensively evaluated, and the energy metabolism in ICH was anchored. The core position of the nitrogen metabolism pathway in brain metabolism in ICH was found for the first time. Carbonic anhydrase 1 (Ca1), carbonic anhydrase 2 (Ca2), and glutamine synthetase (Glul) participated in this pathway. We constructed the protein–protein interaction (PPI) networks for the energy metabolism of ICH, including the Atp6v1a‐Atp6v0c‐Atp6v0d1‐Ppa2‐Atp6ap2 network. Conclusions: It seems that dysregulation of energy metabolism, especially nitrogen metabolism, may be a major cause in secondary ICH injury. This information provides novel insights into secondary events following ICH. An iTRAQ‐based quantitative proteomics was utilized to detect proteins in secondary ICH injury. The energy metabolism of ICH, especially nitrogen metabolism, was anchored on the basis of bioinformatics analysis. Researches on ICH pathogenesis will help to identify novel therapeutic targets. [ABSTRACT FROM AUTHOR]

In order to improve the high‐density culture of microalgae, the traditional flat‐plate photobioreactors were modified with parallel baffles with different structures. The mixing characteristics of triphase flow in four types of bioreactors were investigated using the numerical simulation and experiments. The comparison shows that the results of simulations are consistent with those of experiments. The photobioreactor with ladder‐type parallel baffle could produce multiintensification functions of flow mixing, mass transfer, and bioreaction so that its integrated performances on high‐density culture are more prominent than other bioreactors. The culturing experiments were carried out in a bioreactor fed with air containing 10% CO2 at a flow rate of 10 L min−1. The results show that the growth rate of Chlorella vulgaris reaches 0.783 g L−1 d−1 with a total biomass of 7.21 g L−1 within 6 days, further achieving the efficient high‐density prolonged culture with multiperiods, which is significant for industrial applications. [ABSTRACT FROM AUTHOR]

(J. Sep. Sci. 2015, 38, 1100–1108) DOI: 10.1002/jssc.201401197 Damage of the blood‐brain barrier is a common result of traumatic brain injury. This damage can open the blood‐brain barrier and allow drug passage. An ultra‐performance liquid chromatography–tandem mass spectrometry method was established to determine the concentration of rhein in the biofluids (plasma and cerebrospinal fluid) of patients with a compromised blood‐brain barrier following traumatic brain injury after rhubarb administration. Furthermore, the pharmacokinetic profiles were analyzed. A triple‐quadruple tandem mass spectrometer with electrospray ionization was used for rhein detection. The mass transition followed was m/z 283.06→239.0. The calibration curve was linear in the concentration range of 10‐4000 ng/mL for the biofluids. The intra‐ and inter‐day precisions were less than 10%. The Relative Standard Deviation of recovery was less than 15% in biological matrices. The pharmacokinetic data showed that rhein was rapidly transported into biofluids, and exhibited a peak concentration 1 h after administration. The elimination rate of rhein was slow. The AUCcerebrospinal fluid/AUCplasma of rhein was approximately 17%, indicating that portions of rhein could pass the impaired blood‐brain barrier. The method was successfully applied to quantify rhein in the biofluids of all patients. The data presented can help to guide clinical applications of rhubarb for treating traumatic brain injury. [ABSTRACT FROM AUTHOR]

The title molecule, C26H46O4, has symmetry. The non-H atoms of the octyloxy and methoxymethyl chains are almost coplanar with the benzene ring. There are weak C—H...O hydrogen bonds and C—H...π-ring interactions in the structure. The molecules are loosely packed in the structure. The unit-cell volume is 20% larger than is expected from the empirical rule pertinent to organic compounds, which states that the unit-cell volume (Å3) is approximately equal to the number of non-H atoms in the unit cell multiplied by 18. [ABSTRACT FROM AUTHOR]