CT and MRI findings of intra-parenchymal and intra-ventricular schwannoma: a series of seven cases.

OBJECTIVE: To analyze the computed tomography (CT) and magnetic resonance imaging (MRI) features of patients with intra-parenchymal and intra-ventricular schwannoma. METHODS: The CT and MRI features of seven cases with intra-parenchymal and intra-ventricular schwannoma were analyzed retrospectively. RESULTS: There were four men and three women (median age, 25 years; range, 12-42 years) in this study. The median tumor size was 4.4 cm (range, 3.1-6.5 cm). The mass was, respectively, round in four cases (57.1%), lobulated in two cases (28.6%) and oval in one case (14.3%). All tumors were well-circumscribed. Septa in the mass could be observed in three cases (42.9%), and nodular calcification was observed in two cases (28.6%), which peritumoral edema (n = 3, 42.9%) and hydrocephalus (n = 3, 42.9%) could be observed. Most of these lesions (n = 6) presented iso-hypointensity on T1-weighted images and iso-hyperintensity on T2-weighted images, except one lesion showing low intensity on T2WI. In addition, a fluid-fluid level was observed in one case. After contrast agents' injection, all masses illustrated heterogeneously moderate to marked enhancement. CONCLUSIONS: A well-defined solid and cystic mass with calcification and moderate to marked delayed enhancement may be an objective account of intra-parenchymal or intra-ventricular schwannoma.

Application of Copper(II)-Organic Frameworks Bearing Dilophine Derivatives in Photocatalysis and Guest Separation.

The functionalized design of metal-organic frameworks (MOFs) has been rapidly developed in the last 20 years, and its broad applicability has been demonstrated in many fields. MOFs with desired functions can be assembled using predesigned organic linkers with specific metal nodes, which possess the ordered functional sites and open structures. Although a large number of carboxylic acid junctions have been used to construct MOFs, it is still a great challenge to realize their multifunctionality. In particular, there is a relative lack of research on MOFs as direct photocatalysts, which require not only abundant active sites and open structures but also adsorption groups and effective electron-hole separation performance. To this end, MOFs constructed from the carboxylic acid ligands derived from lophine-based derivatives and copper ions were deliberately used as a photocatalyst, and then, their application in dye degradation and aromatic alcohol conversion was investigated. In addition, in combination with the abundant Lewis sites of copper ions and imidazole sites, the material shows not only the adsorption and separation of C2 series and dyes but also the application of dye degradation and conversion of aromatic alcohols under illumination conditions. The corresponding results fully illustrate that the MOF constructed by using lophine derivatives can be an effective way to prepare photocatalysts. The subsequent research ideas will focus on designing a series of MOFs constructed with multilinked moieties of lophine groups and exploring their application strategies in the field of photocatalysis.

An Ultrastable 155-Nuclei Silver Nanocluster Protected by Thiacalix[4]arene and Cyclohexanethiol for Photothermal Conversion.

Thiacalix[4]arenes have emerged as a family of macrocyclic ligands to protect metal nanoparticles, but it remains a great challenge to solve the mystery of their structures at the atomic level, especially for those larger than 2 nm. Here, we report the largest known mixed-valence silver nanocluster [Ag155 (CyS)40 (TC4A)5 Cl2 ] (Ag155) protected by deprotonated cyclohexanethiol (CySH) and macrocyclic ligand p-tert-butylthiacalix[4]arene (H4 TC4A). Its single-crystal structure consists of a metallic core of four concentric shells, Ag13 @Ag42 @Ag30 @Ag70 , lined with a organic skin of 40CyS- and 5TC4A4- and 2Cl- . Ag155 manifests an unusual pseudo-5-fold symmetry dictated by the intrinsic metal atom packing and the regioselective distribution of mixed protective ligands. This work not only reveals a macrocyclic ligand effect on the formation of a large silver nanocluster, but also provides a new structural archetype for comprehensively perceiving their interface and metal kernel structures.

Simple and Feasible Detection of Hepatitis B Virus via Combination of Multienzyme Isothermal Rapid Amplification and Lateral Flow Dipstick Strip.

Hepatitis B virus infection is not only a huge burden in the field of social health but also a major public health problem that affects the lives and health of the people. Simple, rapid, feasible detection of HBV is critical for its prevention and spread, especially in the developing countries with low-resource laboratories. To this end, we combined multienzyme isothermal rapid amplification (MIRA) and lateral flow dipstick (LFD) strip to detect HBV. A pair of primers targeting the conserved region of HBV genome was designed and used in MIRA-LFD assay. Our results found that the entire amplification of MIRA-LFD only takes 10 min at 37°C and the dilution of the amplification products was added in the LFD strip and observed by the naked eye after 10 min. The detection sensitivity of this method can reach 10 pg. The 45 clinical samples were detected by MIRA-LFD and real-time PCR. The accuracy rate of MIRA-LFD was 100%. Therefore, these characteristics of our newly developed MIRA-LFD assay make it particularly useful and suitable for detecting HBV in the resource-limited condition.

Different Silver Nanoparticles in One Crystal: Ag210 (i PrPhS)71 (Ph3 P)5 Cl and Ag211 (i PrPhS)71 (Ph3 P)6 Cl.

Two pure silver nanoparticles (Ag210 (i PrPhS)71 (Ph3 P)5 Cl and Ag211 (i PrPhS)71 (Ph3 P)6 Cl labeled as SD/Ag210 and SD/Ag211 (SD=SunDi), were found to co-crystallize in forming compound 1. Single-crystal X-ray diffraction (SCXRD) revealed that they differ by only one Ag(PPh3 ). Their four-shell nanoparticles consist of three pure Ag metal shells (Ag19 @Ag52 @Ag45 ) shielded by a silver-organic Ag89 (i PrPhS)71 Cl[Ag(Ph3 P)]n outermost shell. The number (n) of Ag(Ph3 P) is five for SD/Ag210 and six for SD/Ag211. The pseudo-fivefold symmetric Ag nanoparticles exhibit surface plasmon absorption similar to a true metallic state but at the nanoscale. This work exemplifies the important effects of phosphine in stabilizing large silver nanoparticles; and offers a platform to investigate the origin of differences in nanoscale metal materials, even differing by only one metal atom; it also sheds light on the regioselective binding of auxiliary Ph3 P on the surface of silver nanoparticles.

Narrow-band blue emitting nitridomagnesosilicate phosphor Sr8Mg7Si9N22:Eu2+ for phosphor-converted LEDs.

We report a novel narrow-band blue emitting phosphor Sr7.92Mg7Si9N22:0.08Eu2+. The crystal structure of Sr8Mg7Si9N22 is composed of corner-sharing and edge-sharing [SiN4] tetrahedra and distorted square-pyramid [MgN5] polyhedra. Under 350 nm excitation, Eu2+ doped Sr8Mg7Si9N22 emits narrow-band blue light with maximum intensity at 450 nm and a fwhm of 38 nm.

A flexible and superhydrophobic upconversion-luminescence membrane as an ultrasensitive fluorescence sensor for single droplet detection.

A Ln3+-doped (Yb3+, Tm3+ or Yb3+, Er3+ co-doped) NaYF4 nanoparticle/polystyrene hybrid fibrous membrane (HFM) was fabricated using an electrospinning technique. The HFM shows upconversion luminescence (UCL), flexibility, superhydrophobicity and processability. The UCL membrane can be used as a fluorescence sensor to detect bioinformation from a single water droplet (~10 µl). Based on the fluorescence resonance energy transfer, the detection limits of this sensor can reach 1 and 10 ppb for the biomolecule, avidin, and the dye molecule, Rhodamine B, respectively, which are superior to most of the fluorescence sensors reported in previous works. After the fluorescence detection, the target droplet was easily removed without residues on the UCL membrane surface due to its superhydrophobic property, which exhibits an excellent recyclability that cannot be achieved by traditional liquid-based detection systems.

Artificial photosynthetic hydrogen evolution over g-C3N4 nanosheets coupled with cobaloxime.

We report an economic and noble-metal-free artificial photosynthetic system, consisting of g-C3N4 as a photosensitizer and a photocatalyst, and cobaloxime as a co-catalyst, for H2 generation. This system allows for effective electron transfer from excited g-C3N4 to Co(III)(dmgH)2pyCl to generate reduced cobaloxime intermediate species for efficient H2 evolution. Transient fluorescence studies reveal that the presence of cobaloxime and TEOA promotes the population of excited electrons to transfer from g-C3N4, which is responsible for the high photocatalytic activity of this g-C3N4-cobaloxime conjugation system.

Crystal structure of the mucin-binding domain of Spr1345 from Streptococcus pneumoniae.

The surface protein Spr1345 from Streptococcus pneumoniae R6 is a 22-kDa mucin-binding protein (MucBP) involved in adherence and colonization of the human lung and respiratory tract. It is composed of a mucin-binding domain (MucBD) and a proline-rich domain (PRD) followed by an LPxTG motif, which is recognized and cleaved by sortase, resulting in a mature form of 171 residues (MF171) that is anchored to the cell wall. We found that the MucBD alone possesses comparable in vitro mucin-binding affinity to the mature form, and can be specifically enriched at the surface of human lung carcinoma A549 cells. Using single-wavelength anomalous dispersion (SAD) phasing method with the iodine signals, we solved the crystal structure of the MucBD at 2.0Å resolution, the first structure of MucBDs from pathogenic bacteria. The overall structure adopts an immunoglobulin-like fold with an elongated rod-like shape, composed of six anti-parallel ß-strands and a long loop. Structural comparison suggested that the conserved C-terminal moiety may participate in the recognition of mucins. These findings provided structural insights into host-pathogen interaction mediated by mucins, which might be useful for designing novel vaccines and antibiotic drugs against human diseases caused by pneumococci.