Bupleurum chinense DC polysaccharides attenuates lipopolysaccharide-induced acute lung injury in mice

Bupleurum chinense DC had hepato-protective, anti-inflammatory, antipyretic, analgesic, and immunomodulatory effect in traditional Chinese medicine. This study was to determine whether the crude polysaccharides isolated from the roots of Bupleurum chinense DC (BCPs) attenuated lipopolysaccharide (LPS)-induced acute lung injury in mice. Mice were challenged with LPS intratracheally 2 h before BCPs (20, 40 and 80 mg/kg) administration. The bronchoalveolar lavage fluid (BALF) was collected 24 h after LPS challenge. Treatment with BCPs reduced lung wet-to-dry weight ratio. The elevated number of total cells and protein concentration in BALF was reduced. The increased level of myeloperoxidase (MPO), tumor necrosis factor-α (TNF-α) in BALF, and serum nitric oxide (NO) were also inhibited. BCPs significantly attenuated lung injury with improved lung morphology and reduced complement deposition. These results suggested that the effect of BCPs against ALI might be related with its inhibitory effect on excessive activation of complement and on the production of proinflammatory mediators.     

Immunological properties of Fc receptor on lymphocytes. 6. Characterization of suppressive B-cell factor (SBF) released from Fc receptor-bearing B cells.

EA, i.e., antigen-antibody complexes are able to induce an antigen-nonspecific suppressive factor(s) from FcR⁺ B cells by binding on FcR. This factor, termed “suppressive B-cell factor (SBF)” was only effective on H-2 compatible, but not on H-2 incompatible spleen cells in an adoptive cell transfer system. Furthermore, SBF, prepared from B10.A (H-2^a) splenic FcR⁺ B cells, suppressed the adoptive primary response of B10.D2 mice (H-2^d), in addition to A/J mice (H-2^a) against DNP-DE, by the pretreatment of cells with SBF in vitro. Absorption with affinity columns demonstrated that active components) of SBF from C3H/He mice (H-2^k) was eliminated by both B6 anti-CBA (H-2^b anti-H-2^k) and B10.D2 anti-B10.BR (H-2^d anti-H-2^k), but not B10 anti-B10.A (H-2^b anti-H-2^a). In contrast, the suppressive activity of SBF was eliminated neither by anti-mouse Ig nor by a heat-aggregated human γ-globulin column. These results indicate that SBF contains a product coded by the right-hand side of H-2 gene complex, but does not contain Ig determinants nor FcR. Thus, it is conceivable that a compatibility of the right-hand side of H-2 gene complex is required for inducing effective suppression of spleen cells by SBF. SBF was considered to be a trypsin-resistant and heat-labile substance with a molecular weight of 30,000–63,000. The target cells for SBF were FcR^? B precursors, but not helper T cells.     

Identification of Catalytically Active Groups of Penicillium canescens F-436 β-Galactosidase

The functional groups of Penicillium canescens F-436 b-galactosidase have been identified. The pK values and heats of ionization of these groups and photoinactivation of the enzyme with methylene blue indicate that the active site contains carboxyl and imidazole groups. A mechanism for the participation of these groups in the cleavage of the glycoside bond in lactose is proposed.     

Sensitized site-specific photomodification of ssDNA by binary systems of oligonucleotide conjugates: VI. Effect of substituents in the sensitizer anthracene residue

Photomodification of ssDNA by binary systems of oligonucleotide conjugates complementary to the adjacent sequences of the target DNA was studied. One of the conjugates comprised a substituted anthracene as a sensitizer; the other,p-azidotetrafluorobenzaldehyde 3-aminopropionylhydrazone as a photoreagent. The sensitized photomodification is initiated by the 365–580-nm light through an efficient energy transfer from the photoexcitated sensitizer onto the photoreagent in a complementary complex of the binary system with the DNA target where the sensitizer and the photoreagent are sterically converged. Influence of substituents in the anthracene residue on the efficiency of the DNA sensitized photomodification was considered. The oligonucleotide conjugate of anthracene-9-al 3-aminopropionylhydrazone allows highly specific initiation of the sensitized photomodification upon irradiation with visible light at >460 nm in conditions generating no photoreaction in the sensitizer’s absence. For Part V, see [1]; prefix “d” in designations of oligonucleotides is omitted.     

Bifunctional Moth‐Eye Nanopatterned Dye‐Sensitized Solar Cells: Light‐Harvesting and Self‐Cleaning Effects

A nanopatterning technique using nanostamps that provides a facile process to create a nature‐inspired moth‐eye structure achieving high transmittance in the visible range as well as a self‐cleaning effect is reported. Commercially available perfluoropolyether (PFPE) and NOA63 as the mold resin and second replica mold material, respectively, play an important role in fabricating the structure. The structure is found to increase transmittance up to 82% at 540 nm and contact angle up to 150°, representing superhydrophobicity even without the aid of a fluorinated self‐assembled monolayer (SAM) coating. The resulting solid‐state dye‐sensitized solar cells (ssDSSCs) with moth‐eye structures show enhancement of efficiency to 7.3% at 100 mW cm^?2, which is among the highest values reported to date for N719 dye‐based ssDSSCs. This nature‐inspired nanopatterning process could be used for improving light harvesting in any type of photovoltaic cell, and it produces superhydrophobic surfaces, which in turn lead to self‐cleaning for long‐term stability.     

Extended π‐Bridge in Organic Dye‐Sensitized Solar Cells: the Longer,the Better?

The elongation of π‐conjugated bridges between the donor (D) and the acceptor (A) represents a feasible strategy towards enhancement of light‐harvesting in both breadth and depth of organic D‐π‐A dyes suitable for nanocrystalline TiO₂‐based dye‐sensitized solar cells (DSSCs). Here, a series of organic dyes with elongating conjugated bridges is synthesized and characterized. DSSC devices employing a cobalt (II/III) redox electrolyte are fabricated using these dyes as light‐harvesting sensitizers. Compared to a dye with the 3,4‐ethylenedioxythiophene (EDOT) linker ( G188 ), the three counterparts with further extended π‐bridges present gradually red‐shifted electronic absorption spectra and a persistent decrease in oxidation potential. The photocurrent action spectra show that the extension of π‐conjugated bridges decreases the open‐circuit photovoltage. The best performance is shown in G268 with a short‐circuit photocurrent density (J_sc) of 16.27 mA cm², an open‐circuit photovoltage (V_oc) of 0.83 V, and a fill factor (FF) of 0.67, corresponding to an overall conversion efficiency of 9.24%. Unexpectedly, G270, which has with the longest π‐bridge , showed the lowest J_sc, V_oc, and efficiency.     

Atomic Layer Deposition of Highly Transparent Platinum Counter Electrodes for Metal/Polymer Flexible Dye‐Sensitized Solar Cells

Atomic layer deposition (ALD) is used to deposit Pt nanoparticles at low temperature (25–150 °C) to fabricate highly transparent counter electrodes (CEs) for flexible dye‐sensitized solar cells (DSCs). The Pt nanoparticles (NPs) are deposited for different number of ALD cycles on indium tin oxide (ITO)/polyethylene naphthalate (PEN) substrates. Rutherford backscattering spectroscopy (RBS) and transmission electron microscopy (TEM) are used to assess the Pt NP loading, density, and size. There is a trade‐off between transparency and catalytic activity of the CE, and the best cell performances of back‐side‐illuminated DSCs (≈3.7% efficiency) are achieved for Pt ALD at temperatures in the range of 100–150 °C, even though deposition at 25 °C is also viable. The best cell produced with ALD platinized CE (100 cycles at 100 °C) outperforms the reference cells fabricated with electrodeposited and sputtered Pt CEs, with relative improvements in efficiency of 19% and 29%, respectively. In addition, these parameters are used to fabricate a large area CE for a sub‐module (active area of 17.6 cm²), resulting in an efficiency of 3.1%, which demonstrates the scalability of the process.