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Mixed phase materials in the quasi binary diopside (CaMgSi2O6) – molybdite (MoO3) system were synthesized by a precipitation method. Materials were fabricated with diopside to molybdite ratios of 1:0, 10:1, 5:1, 2:1 and 1:1. XRD, SEM and EDS results show that alongside the initial diopside phase, phases such as calcium molybdate CaMoO4, rod-like enstatite MgSiO3 and cristobalite SiO2 formed as the molybdite content increased, and diopside was entirely absent at the highest molybdite content. At lower Mo content, mixed phase materials showed higher hardness and slower biodegradation in SBF relative to pristine diopside, while maintaining reasonable hydroxyapatite (HAp) formation capability. In contrast, materials with higher molybdite content exhibited lower hardness and bioactivity. The variation in the mechanical and bioactive performance could be attributed to the presence of bulk CaMoO4, acting as a reinforcement, and rod-like MgSiO3 with a highly porous and fragile structure. The trend of hardness is not consistent to the proportion of the component phases could be attributed to morphologies, interfaces, and densities of the samples. Both of secondary phases had poorer HAp deposition compared to pure diopside, indicating the MoO3 addition lowered mixed phase CaMgSi2O6 – MoO3 bioceramics’ ability to form Hap. The results suggest that moderate addition of molybdite to diopside would be an effective pathway towards crystalline bioceramics with enhanced performance.

Flame retardants have important theoretical research and applied value for lithium-ion battery safety. Microcapsule flame retardants based on ammonium polyphosphate (APP) and aluminum hydroxide (ATH) were synthesized for application in lithium-ion batteries. First, the ATH-APP was prepared by coating a layer of ATH on the surface of the core APP. Then, the ATH-APP was encapsulated by poly(urea-formaldehyde) (PUF) to obtain en-ATH-APP. The structure and flame-retardant property of en-ATH-APP, the influence of en-ATH-APP on the thermal stability of the electrode, and the electrochemical performance of the battery were studied. The results of Fourier transform infrared and scanning electron microscope experiments indicated that APP was coated with ATH and PUF in turn. The results of differential scanning calorimetry and the fire extinguishing test for electrodes manifested that en-ATH-APP had better flame-retardant property than APP because of the synergistic effect between APP and ATH. Moreover, the flame-retardant efficiency of en-ATH-APP was comparable to that of ATH-APP, indicating that the presence of PUF had almost no effect on the flame-retardant property. The results of electrochemical experiments indicated that en-ATH-APP had the best electrochemical compatibility for the battery compared with APP and ATH-APP. The research lights the way to improve inherent safety of lithium-ion batteries by adding en-ATH-APP to the cathode.

Tropomyosin (TM) is the major shrimp allergen that could trigger anaphylactic reactions. Recently, recombinant TM (rTM) has been accepted widely in the field of allergen-specific immunotherapy. While the allergenicity of rTM has not been compared with natural TM (nTM) based on in vitro digestion profile. In this work, IgG-/IgE binding, allergen peptides and degranulation ability of the digested samples in simulated gastric fluid (SGF) /simulated intestinal fluid (SIF) /gastrointestinal (GI) from nTM and rTM were evaluated by immunoassay assays, proteomics and basophil degranulation assay. Results showed that pepsin-digested and trypsin-digested samples of rTM exhibited lower IgG-/IgE binding and degranulation than those of nTM. More peptides of digested samples from rTM (57.8%) matched shrimp allergic epitopes than those from nTM (33.3%). While, the peptide of SITDELDQTF (269-278) appeared most frequently. These findings would supply foundation data for epitope-based immunotherapy to shrimp allergic individuals.

The design and synthesis of new filtration materials for high-temperature particulate matter capture are of both technological and scientific importance but still remain a challenging task. In the current work, we presented an approach for the manufacturing of highly porous SiC cellular ceramics by combining polyether polyol-modified carbon black with polyurethane foaming method. Hydroxyl groups were introduced to the surface of carbon black to prevent agglomeration. As-obtained SiC cellular ceramic possed three-dimensional interconnected reticular architecture with the abundant micron-sized window on its cell wall. The resulting porous SiC ceramic exhibited a high removal efficiency (95.8%) with extremely low pressure drop (38 Pa). The successful fabrication of such fascinating material may provide new insights for high-temperature particulate matter filtration.

Dual‐modality imaging employing complementary modalities, such as all‐optical ultrasound and photoacoustic imaging, is emerging as a well‐suited technique for guiding minimally invasive surgical procedures. Quantum dots are a promising material for use in these dual‐modality imaging devices as they can provide wavelength‐selective optical absorption. The first quantum dot nanocomposite engineered for co‐registered laser‐generated ultrasound and photoacoustic imaging is presented. The nanocomposites developed, comprising CuInS2 quantum dots and medical‐grade polydimethylsiloxane (CIS‐PDMS), are applied onto the distal ends of miniature optical fibers. The films exhibit wavelength‐selective optical properties, with high optical absorption (> 90%) at 532 nm for ultrasound generation, and low optical absorption (< 5%) at near‐infrared wavelengths greater than 700 nm. Under pulsed laser irradiation, the CIS‐PDMS films generate ultrasound with pressures exceeding 3.5 MPa, with a corresponding bandwidth of 18 MHz. An ultrasound transducer is fabricated by pairing the coated optical fiber with a Fabry–Pérot (FP) fiber optic sensor. The wavelength‐selective nature of the film is exploited to enable co‐registered all‐optical ultrasound and photoacoustic imaging of an ink‐filled tube phantom. This work demonstrates the potential for quantum dots as wavelength‐selective absorbers for all‐optical ultrasound generation., Bilayer nanocomposites comprising CuInS2 quantum dots within micron‐scale polydimethylsiloxane host layers are microfabricated with dip‐coating on the distal ends of optical fibers. The wavelength‐selective optical absorption (high from 400 to 600 nm; low from 700 to 1200 nm) is well‐suited to multimodality optical ultrasound and photoacoustic imaging of biological tissue structures such as atherosclerotic plaque.

Background and aims Hepatitis B virus (HBV) integrations are common in hepatocellular carcinoma (HCC). In particular, alterations of the telomerase reverse transcriptase (TERT) gene by HBV integrations are frequent; however, the molecular mechanism and functional consequence underlying TERT HBV integration are unclear. Approach and results We adopted a targeted sequencing strategy to survey HBV integrations in human HBV-associated HCCs (n = 95). HBV integration at the TERT promoter was frequent (35.8%, n = 34/95) in HCC tumors and was associated with increased TERT mRNA expression and more aggressive tumor behavior. To investigate the functional importance of various integrated HBV components, we employed different luciferase reporter constructs and found that HBV enhancer I (EnhI) was the key viral component leading to TERT activation on integration at the TERT promoter. In addition, the orientation of the HBV integration at the TERT promoter further modulated the degree of TERT transcription activation in HCC cell lines and patients' HCCs. Furthermore, we performed array-based small interfering RNA library functional screening to interrogate the potential major transcription factors that physically interacted with HBV and investigated the cis-activation of host TERT gene transcription on viral integration. We identified a molecular mechanism of TERT activation through the E74 like ETS transcription factor 4 (ELF4), which normally could drive HBV gene transcription. ELF4 bound to the chimeric HBV EnhI at the TERT promoter, resulting in telomerase activation. Stable knockdown of ELF4 significantly reduced the TERT expression and sphere-forming ability in HCC cells. Conclusions Our results reveal a cis-activating mechanism harnessing host ELF4 and HBV integrated at the TERT promoter and uncover how TERT HBV-integrated HCCs may achieve TERT activation in hepatocarcinogenesis.

Dishevelled-3 (Dvl3) is regarded as a binding hub with many different interacting partners. However, its regulation and mechanism on cancer stemness remain to be explored. In this study, we showed that Dvl3 was significantly overexpressed in human hepatocellular carcinomas (HCCs) and promoted cancer stemness both in vitro and in vivo. We found that the non-phosphorylated (NP)-Dvl3 was more stable than the phosphorylated form, more active in activating β-catenin transcriptional activity, and more potent in enhancing self-renewal ability in HCC cells. Mechanistically, we confirmed that the homeodomain-interacting protein kinase-2 (HIPK2) and E3 ubiquitin ligase ITCH were able to physically bind to Dvl3 protein. Knockdown of HIPK2 and the protein phosphatase regulatory unit C-alpha (PP1Cα) resulted in sustained Dvl3 phosphorylation and hence decrease in the NP form of Dvl3. On the other hand, knockdown of E3 ubiquitin ligase ITCH reduced the phosphorylation-induced degradation and stabilized the phosphorylated Dvl3 protein. Furthermore, the NP-Dvl3 enhanced the LGR5 promoter activity to upregulate LGR5 expression, which was associated with increased cancer stemness in HCC. Our findings established that HIPK2/PP1Cα/ITCH axis sustains the de-phosphorylation of Dvl3. This post-translational modification of Dvl3 in turn maintains LGR5 expression and enhances the cancer stemness properties in HCC., published_or_final_version

Due to the rapid growth in the use of blue-light-based electrical panels and much brighter lighting environments, the socioeconomic impact by retinal light injury is critical. Understanding the material property and mechanisms underlying this hazard is important for both effective and user-friendly product development. The InGaN based blue LED has been applied to excite the yellow phosphor (Y3Al5O12:Ce3+) for white light generation. In this study, custom-made phosphor-converted white light emitting diode (pc-WLED) with correlated color temperature (CCT) ranging from 2700K to 6500K were used for exposure treatments to assess the potential retinal injury. We examined LED induced retinal neuronal cell damage in a rat model through functional and histopathological measurements. Electroretinography (ERG), hematoxylin and eosin (H&E) staining, and transmission electron microscopy (TEM) were used for pathological examinations. The experimental results indicate that blue-rich-LED light could induce more photochemical injury to the retina after the exposure. The results of this study suggest that retinal injury is mainly induced by photosensitizer-and photopigment-mediated oxidative stress with color temperature dependent effect, and users should be more aware of this effect before switching to LED lamps for domestic lighting.

Using (S)-prolinol as a chiral auxiliary, axially chiral vinylallenes with excellent enantiopurity (up to >99% enantiomeric excess (ee)) were readily prepared from optically pure propargylamines in...

A confirmatory and quantitative method based on liquid chromatography–tandem mass spectrometry (LC/MS/MS) has been developed for the determination of low-level residues of three antibiotic dyes and two metabolites in fish muscle and feed. The target compounds include methylene blue (MB), crystal violet (CV), leucocrystal violet (LCV), malachite green (MG), and leucomalachite green (LMG). The procedures involve solvent extraction by 50% McIlvaine’s buffer with acetonitrile, followed by solid phase extraction (SPE) with an MCX cartridge. High performance liquid chromatography (HPLC) and positive electrospray ionization (ESI) MS with multiple reaction monitoring of two transition reactions was applied for each compound. The detected ion ratios of MB, CV, LCV, MG, and LMG were 11.8, 34.9, 88.4, 25.6, and 42.0, respectively. The average fortification recoveries of the MB, CV, LCV, MG, and LMG of the level of 0.8 μg/kg tested in fish muscle and feed samples were 99.68, 98.93, 100.49, 100.01, and 100.00%, respectively. The precision of analysis of analytes in fish muscle and feed ranged from 4% to 14% and from 7% to 14%, respectively. The decision limits (CCα) were 0.28–0.54 μg/kg, and the detection capabilities (CCβ) were 0.35–0.67 μg/kg ( n = 99).

Aim To examine light-emitting-diode (LED)-induced retinal neuronal cell damage and its wavelength-driven pathogenic mechanisms. Methods Sprague-Dawley rats were exposed to blue LEDs (460 nm), green LEDs (530 nm), and red LEDs (620 nm). Electroretinography (ERG), Hematoxylin and eosin (H&E) staining, transmission electron microscopy (TEM), terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and immunohistochemical (IHC) staining, Western blotting (WB) and the detection of superoxide anion (O2-·), hydrogen peroxide (H2O2), total iron, and ferric (Fe3+) levels were applied. Results ERG results showed the blue LED group induced more functional damage than that of green or red LED groups. H&E staining, TUNEL, IHC, and TEM revealed apoptosis and necrosis of photoreceptors and RPE, which indicated blue LED also induced more photochemical injury. Free radical production and iron-related molecular marker expressions demonstrated that oxidative stress and iron-overload were associated with retinal injury. WB assays correspondingly showed that defense gene expression was up-regulated after the LED light exposure with a wavelength dependency. Conclusion The study results indicate that LED blue-light exposure poses a great risk of retinal injury in awake, task-oriented rod-dominant animals. The wavelength-dependent effect should be considered carefully when switching to LED lighting applications.

Rhodium(III) porphyrin complexes [Rh(Por)Me] are catalytically active towards stereoselective intramolecular carbene C–H insertions of α-diazoacetamides to give cis-β-lactams or trans-γ-lactams in yields up to 99% with regioselectivities up to 100% and cis/trans ratios up to 83:17 for β-lactams.

A chemosensor ( R )- OH bearing an amino alcohol group was synthesized for the highly selective fluorescent recognition of Al 3+ with low limit of detection (16 ppb ). “Turn-on” type fluorescence changes were observed upon the addition of Al 3+ in aqueous solution. The significant enhancement (35.4-fold) of fluorescence intensity was ascribed to the complex formation between ( R )- OH and Al 3+ which denoted as the chelation-enhanced fluorescence (CHEF) process.

The reaction-based relay recognition of fluoride and cyanide anions was demonstrated for the first time, with rapid response and unique triple (fluorescence color, intensity and absorption band) output modes in either of two sequential sensing events. Ratiometric determination of these two anions by fluorescence and/or absorbance spectra is also achieved.

A new class of organic molecular probes (1–3) based on a 1,3-disubstituted diethynylbenzene core has been developed. Both 1 and 2 (with the esters of 1 replaced by diethylamides in 2) show good linear and three-photon induced photophysical properties with two-photon absorption cross-sections (185–210 cm4 s photon–1 molecule–1) that are suitable for biological applications in live specimens. The propeller π-conjugated systems of 3 (a C3 analogue of 1) shows threefold enhancement for the two-photon absorption cross-section (650 cm4 s photon–1 molecule–1). Solvatochromism was observed in the fluorescence spectra of all these molecular probes; in acidic medium (pH = 4–5) their fluorescence emissions are slightly blueshifted with a threefold enhancement in intensity relative to those observed under basic conditions (pH = 10–11). In the fluorometric titration study against a variety of bioactive small molecules, only 2 shows strong binding affinity (log KB > 7) towards citrates and bicarbonates with approximately 30 nm redshift. The in vitro emission spectra of 2 obtained show the same emission upon addition of anions to the solution. The results of these studies could provide new molecular-design strategies for two-photo absorption (TPA) chromophores and new materials for two/multi-photon imaging in vitro.

Several rhodamine-B (C.I. Basic Violet 10) hydrazide derivatives were employed as specific fluorescent and colorimetric chemosensors for Cu 2+ in neutral buffered media. The probes exhibited selective “off-on” type changes in both absorption and emission spectra toward Cu 2+ ions compared to other metal cations, which was attributed to transformation of the non-fluorescent and colorless spirolactam derivative to the ring-opened, fluorescent, pink coloured amide. Further studies of structure-activity relationship revealed that the designated acyl hydrazone skeleton moiety shared by these chemosensors, derived from the dye hydrazide and salicylaldehyde analogues, determines the selectivity for Cu 2+ over other cations.

LongYan kaolin has a large Fe content which affects the coloring. Bioleaching treatments to remove Fe impurities were conducted here using indigenous dissimilatory Fe(III)-reducing bacteria. The factors that affect bioleaching efficiency include bioleaching time, carbon source, pH, temperature, pulp density, and inoculum density and these were examined. Environmental scanning electron microscopy and X-ray diffraction were used to examine any textural or mineralogical changes at the surface of the kaolin that may have occurred during the bioleaching. Iron impurities in the kaolin were reduced from 0.88% to 0.48% with an increase in the natural whiteness index from 60.8% to 81.5% after 7 days of bioleaching treatment. A granulometric analysis of dispersed kaolin demonstrated that the bioleaching resulted in a decrease in particle size. The results demonstrated that the bioleaching was very effective at improving the quality of the kaolin, where insoluble Fe(III), either adsorbed to the kaolin surfaces or admixed as amorphous forms, was leached out by micro organisms as water-soluble Fe(II).

[Wang, Ya-Wen] Lanzhou Univ, Key Lab Nonferrous Met Chem & Resources Utilizat, State Key Lab Appl Organ Chem, Lanzhou 730000, Peoples R China

A chiral BINOL derivative bearing Schiff’s base group has been synthesized for the selective fluorescent recognition of Hg2+. Highly selective “turn-on” type fluorescence changes were observed upon the addition of Hg2+. The fluorescence intensity enhancement was ascribed to the complex formation between (R)-1 and Hg2+ which blocked the photo-induced electron transfer process.

A new approach for high-efficiency polymer solar cells utilizing a BHJ active layer consisting of poly(3-hexylthiophene) (P3HT) as a donor and buckminsterfullerene, C60 as an acceptor was demonstrated. P3HT/C60 BHJ films were made possible by in situ formation of C60 from solubilized addends, C60–CpCO2R (R = Hex, Oct, and EHex) by retro Diels–Alder reaction at, or above, 100 °C. These cells exhibit enhanced performances compared to as-prepared P3HT/C60 BHJ films, showing better morphology.

Pentacene has been actively studied as relevant materials in organic field-effect transistors (OFETs) and organic light-emitting diodes (OLEDs). However, the low solubility and low stability of pentacene in common organic solvents have hindered its applications. When exposed to light or at high concentration, pentacene is found to dimerize easily. Many research groups are currently working on the design and synthesis of novel substituted pentacenes, but few of them systematically reported physical properties such as molecular spectroscopy and electronic properties, which might elucidate the influence of substituents on HOMO–LUMO gaps. Furthermore, the reactive nature of the central ring in pentacenes makes pentacenes good dienes for Diels–Alder reactions. In this paper, a series of soluble 6,13-disubstituted 2,3,9,10-tetrakis(trimethylsilyl)pentacenes were synthesized and characterized. Their reactions, structures, and physical properties were also studied. In addition, bulky o-carboranyl substituted pentacene derivative 15 and 6-chloro-2,3,9,10-tetrakis(trimethylsilyl)pentacene (16) were synthesized for the first time. Compound 16 possesses the largest dihedral angle (7.7° with two adjacent benzene rings) and shows a wave structure. Diels–Alder reactions with acceptable efficiency were carried out between 16 and various dienophiles.

Background Aberrant regulation of histone deacetylases (HDACs) is known to play a pivotal role in HCC pathogenesis as well as other human malignancies. Panobinostat (LBH589) is a pan-HDAC inhibitor covering a wide range of HDACs (Class I, II and IV) with high inhibitory activity at nanomolar concentration. It has been approved by FDA for treating multiple myeloma and has demonstrated promising anti-proliferative and cytotoxic activity in breast, prostate, colon and pancreatic cancer cell lines. This study investigated in vitro and in vivo effect of Panobinostat in HCC cell lines. Methods Basal expressions of HR23B and HDACs of 7 HCC cell lines (HepG2, PLC/PRF/5, Huh-7, Hep3B, SNU-182, SNU-398 and SNU-449) were determined by western blotting. Their corresponding IC50 for 24, 48 and 72 hours towards Panobinostat were determined by cell viability assay. Huh-7, Hep3B and SNU-449 were selected for further in vitro experiments. Their cell cycle distribution after Panobinostat treatment was evaluated by flow cytometry. Apoptosis was detected by Cell Death Detection ELISA. Huh-7 and Hep3B xenograft model were used for in vivo investigation. Cells were inoculated subcutaneously into the flanks of 3-4 week old male athymic nude mice. When tumors were established, Panobinostat was administrated intraperitoneally at 7.5mg/kg and 15mg/kg five days per week for 2 weeks. Results All cell lines were able to achieve nearly 100% growth inhibition and had displayed a dose- and time-dependent manner towards Panobinostat. Maximum growth inhibition was 20-70% at 24hr compared to over 90% at 72hr. There was significant reduction in cell viability at low nanomolar concentrations (IC50 at 48hr: HepG2=8.81±0.72nM, PLC/PRF/5=18.9±0.74nM, Huh-7=14.01±1.12nM, Hep3B=25.00±3.69nM, SNU-182=73.33±15.52nM, SNU-398=12.86±3.25nM, SNU-449=73.01±9.09nM). Flow cytometry analysis showed Panobinostat induced accumulation of cells at G0/G1 phase in Huh-7 and SNU-449. Meanwhile, an increase in sub G1 population was detected in Hep3B after exposure to 25nM Panobinostat for 48h. Apoptotic induction was further confirmed by cell death detection ELISA and western blotting. Panobinostat promoted apoptosis more remarkable in Hep3B than other 2 cell lines as evidenced by a stronger cleaved PARP expression level. Panobinostat treatment delayed tumor growth in Hep3B (p Conclusion Panobinostat has been demonstrated to inhibit in vitro and in vivo HCC cell growth. Further study on the mechanism behind Panobinostat sensitivity is warranted. The study was supported by Novartis. Citation Format: Chi Tung Choy, Wing Yu Man, Chi Hang Wong, Stephen Lam Chan. Preclinical study on the efficacy of Panobinostat in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5059. doi:10.1158/1538-7445.AM2017-5059

There has been great interest recently in applying energetic beams, notably excimer lasers and low temperature plasma (LTP), on polymers for the modification of their surface properties. The interaction produces the characteristic ripple/roll-like structures and changes in physical and chemical properties, resulting in better dyeability and adhesion to coatings, etc. Poly(ethylene terephthalate) (PET) fibres of different draw ratios were selected to investigate the effects of these sources on the surface modification. The effect of laser treatments on LTP irradiated fibres was also studied. It is observed that although the morphological modification features on the PET fibre surface developed under laser and LTP treatments are not identical, they have great similarity. The doubly treated surfaces also reveal some interesting results.

Among some Rh(III)-porphyrin complexes tested, (I) is found to be the most efficient catalyst for the intramolecular carbene C—H insertion of α-diazoacetamides to form β- or γ-lactams with high diastereoselectivity.

Anion to cation relay recognition was designed and realized for the first time with sequence specificity (F(-)→Cu(2+)) via a fluorescence "off-on-off" mechanism. Probe 1 was a highly selective, sensitive, and turn-on chemodosimeter for F(-) through a specific cyclization reaction triggered by the strong affinity of fluoride toward silicon with a significant change of fluorescence color in both ethanol and ethanol-water (1:1, v/v) solution. Fluorescence enhancement factors were dramatic: 833-fold in ethanol and 164-fold in ethanol-water (1:1, v/v) solution, respectively. The in situ system generated from the sensing of F(-) showed good relay recognition ability for Cu(2+) via fast fluorescence quenching by the formation of a 1:1 complex in ethanol-water (1:1, v/v) solution. The isolated pure compound 2 also exhibited high selectivity toward Cu(2+) in PBS buffer (pH = 7.0) solution. The origin of this sequence specificity of fluorescence recognition was disclosed through the crystal or optimized structures and DFT calculations of corresponding compounds.

A highly selective chemodosimeter 1 for cyanide based on the 1,1'-binaphthyl skeleton is described which demonstrated significant visual change and a low limit of detection. Interestingly, a reversible process triggered successively by CN(-) and Au(3+) is also observed and determined by fluorescence, UV-vis spectra, (1)H NMR titration, and ESI-MS.

In order to prevent the risk of volatile organic solvent over exposure in the atmosphere, a sensitive sensing device is needed for detection in common workplaces. Silicon nanowires carrying the high surface-bulk ratio as a unique characteristic could be used for volatile organic solvent sensing. This study proposed to create the sensing device through spontaneous electrochemical reaction. In terms of advantages that silicon nanowire array on volatile organic solvent sensing, sensing of diethyl ether revealed the optimal outcome. The study also discussed the relation of organic solvents molecular and the electrons distribution on silicon nanowires surface, to further weight the impact of the effect on sensing sensitivity.

An organometallic cyclometalated platinum(II) complex, [Pt(L(3))Cl][PF(6)], has been synthesised from a specially designed cyclometalating ligand, HL(3) (triphenyl{5-[3-(6-phenylpyridin-2-yl)-1H-pyrazol-1-yl]pentyl}phosphonium chloride), that contains a pendant carbon chain carrying a terminal cationic triphenylphosphonium moiety. Aside from its room temperature single-photon luminescent properties in solution, [Pt(L(3))Cl](+) can also produce two-photon-induced luminescence at room temperature upon excitation at 700 nm from a mode-locked Ti:sapphire laser. Its two-photon absorption cross-section in DMF at room temperature was measured to be 28.0x10(-50) cm(4) s photon(-1). [Pt(L(3))Cl](+) is able to selectively stain the cell nucleolus. This has been demonstrated by two-photon confocal imaging of live and methanol-fixed HeLa (human cervical carcinoma) and 3T3 (mouse skin fibroblasts) cells. This organelle specificity is likely to be related to its special affinity for proteins within cell nucleoli. As a result of such protein affinity, [Pt(L(3))Cl](+) is an efficient RNA transcription inhibitor and shows rather profound cytotoxicity. On the other hand, the organelle-specific labelling and two-photon-induced luminescent properties of [Pt(L(3))Cl](+) renders it a useful nuclear dye for the 3-dimensional reconstruction of optical sections of thick tissues, for example, mouse ileum tissues, by multiphoton confocal microscopy.

In order to prevent overexposure to volatile organic solvents (VOCs), a simple sensing device with high sensitivity is needed in the common workplace. Meanwhile, silicon nanowires carrying the high surface-bulk ratio as a unique characteristic could be used for VOCs sensing. This study utilised spontaneous electrochemical reaction, which involves etching of silicon wafer in a silver nitrate and hydrofluoric acid based solution, to modify etching times for silicon nanowires fabrication. This research discovered that the length of nanowire increased and VOCs sensing sensitivity improved as the etching time increased. Furthermore, diethyl ether had the optimal performance on the effect of silicon nanowires array on VOCs sensing. The study also discussed the effect of VOCs molecules and electron distribution on silicon nanowires surface, to further investigate the impact on sensing sensitivity.

A new heteroleptic iridium complex demonstrated low cytotoxicity and near-infrared excitation (via two-photon absorption) for target-specific in vitro Golgi imaging in various cell lines (HeLa and A549 cells) with two-photon absorption cross section (~350 GM) in DMSO.

Hepatocellular carcinoma (HCC) is one of the most common fatal malignancies in the world and is particularly prevalent in China and Southeast Asia. Although the risk factors are well known, the molecular mechanisms underlying hepatocarcinogenesis is unclear. Alteration of Wnt signaling pathway is one of the key events in HCC development and so we performed a low-density array (LDA) analysis on 38 pairs of HCC samples and their corresponding non-tumorous livers to examine the expression profiles of different Wnt signaling components. We found that, among the genes studied, Dishevelled 3 (Dvl3) was significantly overexpressed in HCCs as compared with the corresponding non-tumorous liver tissues. In addition, Dvl3 overexpression in HCC was significantly associated with presence of venous invasion (P = .021). The overexpression result was confirmed by expansion of the sample size using quantitative real-time PCR (q-PCR). Next, we investigated the effects of Dvl3 on the migratory and invasive abilities of HCC cells. We established stable shRNA Dvl3-knockdown clones in PLC/PRF/5 HCC cells and found that knockdown of Dvl3 suppressed the migratory and invasive abilities of HCC cells using transwell migration and invasion assays, respectively, suggesting an enhancing role of Dvl3 in HCC cell movement and cell invasion. Although cell proliferation assay in vitro showed no significant difference between the stable Dvl3 knockdown and non-target control PLC/PRF/5 cells, in vivo study in SCID mice showed that the stable Dvl3-knockdown cells resulted in a lower incidence of tumors formed and a smaller tumor size. Furthermore, since Dvl3 is an upstream regulator of the Wnt/β-catenin pathway, using the TOPFOP luciferase reporter assay, we found that transient transfection of Dvl3 in PLC/PRF/5 and BEL-7402 HCC cell lines enhanced the β-catenin-dependent transcriptional activity. In conclusion, upregulation of Dvl3 was frequent in human HCCs. Dvl3 enhanced cell migration and invasion in vitro and tumorigenicity in vivo in SCID mice, and activated canonical β-catenin pathway. It may play an oncogenic role in HCC development. (This study was funded by Hong Kong Research Grants Council CRF grants (RGC CRF HKU1/06C and HKU 7/CRG/09).) Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1074. doi:10.1158/1538-7445.AM2011-1074

A soluble 2,3,9,10-tetrakis(trimethylsilyl)pentacene (1) was synthesized; the discovery of the radical cationic character of 1 in solution through EPR measurement has provided insights into the sensitivity of acenes towards light and oxygen.

Low relative molecular mass alkyl halides, after in situ derivatization to the corresponding S-alkyl-isothiouronium salts in the presence of an excess of thiourea, were determined with a poly(vinyl chloride) membrane S-alkylisothiouronium-selective electrode based on S-butylisothiouronium tetraphenylborate. This membrane electrode exhibited Nernstian response in the range 1.0 × 10–1–1.6 × 10–4 mol dm–3 with an average cationic (positive) slope of 58.8 mV per concentration decade at 25 °C. The electrode had a reasonably wide working pH range (6.5–8.5), fast dynamic response time (30 s–2 min), stable response for at least 2 months and high selectivity for the S-alkylisothiouronium ion in the presence of many inorganic and organic ions. The electrode functioned satisfactorily for the determination of primary and secondary alkyl halides, excluding alkyl fluorides.

In this study, a method for determination of cholesterol and four phytosterols by gas chromatography coupled with electron impact ionization mode–tandem mass spectrometry without derivatization in general food was developed. The sample was saponified with 7.5% KOH in methanol. After heating on hot plate and reflux for 60 minutes, the saponified portion was extracted with n -hexane/petroleum ether (50:50, v/v). The extracts were evaporated with rotary evaporator and then redissolved with tetrahydrofuran. The tetrahydrofuran layer was transferred into an injection vial and analyzed by gas chromatography on a 30 m VF-5 column. Limit of quantification was 2 mg/kg. Recoveries of cholesterol and four phytosterols from general food were between 91% and 100%.

Imidazole and some 1-alkylimidazoles are methylated at C2 under homolytic methylation conditions. Pyrazole forms 3-methylpyrazole, while 2-substituted imidazoles are unaffected. Some 2-acylimidazoles are prepared and described.