One-Pot Synthesis of Benzoazole-Substituted Thioenamines via a Cross Dehydrogenation Coupling (CDC) Reaction.

An iodine-catalyzed synthesis of benzoazole-substituted thioenamines in a one-pot manner was reported. Using 2-aminothiophenols (or 2-aminophenols or 1,2-phenylenediamines), tetramethylthiuram disulfide (TMTD), and enamines (mainly indoles) as starting materials, the target C(sp)-S formation products (benzoazole-substituted thioenamines) could be furnished smoothly in good yields. The reaction might proceed through an electrophilic substitution pathway in a cross dehydrogenation coupling (CDC) manner.

Confinement of Quantum Dots in between Monolayered Graphene Nanosheets for Arousing Boosted Multifarious Photoredox Selective Organic Transformation.

Transition metal chalcogenide quantum dots (TMC QDs) represent promising light-harvesting antennas because of their fascinating physicochemical properties including quantum confinement effect and suitable energy band structures. However, TMC QDs generally suffer from poor photoactivities and photostability due to deficiency of active sites and ultrafast recombination rate of photoinduced charge carriers. Here, we demonstrate how to rationally arouse the charge transfer kinetic of TMC QDs by close monolayered graphene (GR) encapsulation via a ligand-dominated layer-by-layer (LbL) assembly utilizing oppositely charged TMC QDs and GR nanosheets as the building blocks.

General Layer-by-Layer Assembly of Multilayered Photoanodes: Triggering Tandem Charge Transport toward Photoelectrochemical Water Oxidation.

Modulation of photoinduced charge separation/migration and construction of controllable charge transfer pathway over photoelectrodes have been attracting enduring interest in semiconductor-based photoelectrochemical (PEC) cells but suffer from sluggish charge transport kinetics. Here, we report a general approach to fabricate NP-TNTAs/(TMCs QDs/PSS) (X = Te, Se, S) photoanodes via a facile and green electrostatic layer-by-layer (LbL) self-assembly strategy, for which transition-metal chalcogenides quantum dots (TMCs QDs) [CdX (X = Se, Te, S)] and poly(sodium 4-styrenesulfonate) (PSS) were periodically deposited on the nanoporous TiO nanotube arrays (NP-TNTAs) via substantial electrostatic force, resulting in the continuous charge transfer pathway. NP-TNTAs/(TMCs QDs/PSS) photoanodes demonstrate significantly enhanced solar-driven photoelectrochemical (PEC) water oxidation activities, relative to NP-TNTAs and TMCs QDs under visible and simulated sunlight irradiation, predominantly because of the suitable energy level configuration between NP-TNTAs and TMCs QDs, unique integration mode, and high-speed interfacial charge separation rate endowed by LbL assembly.

Layer-by-Layer Self-Assembly of Metal/Metal Oxide Superstructures: Self-Etching Enables Boosted Photoredox Catalysis.

The capability of noble metal nanoparticles (NPs) as efficient charge transfer mediators to stimulate Schottky-junction-triggered charge flow in multifarious photocatalysis has garnered enormous attention in the past decade. Nevertheless, fine-tuning and controllable fabrication of a directional charge transport channel in metal/semiconductor heterostructures via suitable interface engineering is poorly investigated. Here, we report the progressive fabrication of a tailor-made directional charge transfer channel in Pt nanoparticles (NPs)-inlaid WO (Pt-WO) nanocomposites via an efficient electrostatic layer-by-layer (LbL) self-assembly integrated with a thermal reduction treatment, by which oppositely charged metal precursor ions and polyelectrolyte building blocks were intimately and alternately assembled on the WO nanorods (NRs) by substantial electrostatic interaction.

Partially Self-Transformed Transition-Metal Chalcogenide Interim Layer: Motivating Charge Transport Cascade for Solar Hydrogen Evolution.

Directional and high-efficiency charge transport to the target active sites of photocatalyst is central to boost the solar energy conversion but is retarded by the sluggish charge transfer kinetics and deficiency of active sites. Here, we report the elaborate design of cascade unidirectional charge transfer channel over spatially multilayered CdS@CdTe@MoS dual core-shell ternary heterostructures by partial transformation of CdS to CdTe interim layer followed by seamless encapsulation with an ultrathin MoS layer. The suitable energy-level alignment and unique coaxial multilayered assembly mode among the building blocks accelerate the interfacial charge separation and transport, endowing the CdS@CdTe@MoS heterostructures with conspicuously enhanced visible-light-driven photocatalytic hydrogen generation performances along with good photostability.

Precise Tuning of Coordination Positions for Transition-Metal Ions via Layer-by-Layer Assembly To Enhance Solar Hydrogen Production.

Finely tuning the charge transfer constitutes a central challenge in photocatalysis, yet exquisite control of the directional charge transfer to the target reactive sites is hindered by the rapid charge recombination. Herein, dual separated charge transport channels were fabricated in a one-dimensional transition-metal chalcogenide (TMC)-based system via an elaborate layer-by-layer (LbL) self-assembly approach, for which oppositely charged metal-ion-coordinated branched polyethylenimine (BPEI) and MoS quantum dots (QDs) were alternately integrated to fabricate the multilayered TMC@(BPEI/MoS QDs) heterostructures with controllable interfaces. Photocatalytic hydrogen generation performances of such ternary heterostructures under visible light irradiation were evaluated, which unravels that the BPEI layer not only behaves as "molecule glue" to enable the electrostatic LbL assembly with MoS QDs in an alternate stacking fashion on the TMC frameworks but also acts as a unidirectional hole-transfer channel.

Charge Transport Surmounting Hierarchical Ligand Confinement toward Multifarious Photoredox Catalysis.

Metal nanoparticles (NPs) have been deemed an imperative sector of nanomaterial for triggering the Schottky-junction-driven electron flow in photoredox catalysis, but they suffer from sluggish charge-transfer kinetics, rendering efficient charge flow difficult. Here, we report the construction of unidirectional charge-transfer channel in a metal/semiconductor heterostructure via a ligand-triggered self-assembly method, by which hierarchically branched ligands (DMAP)-capped Pd NPs were controllably attached on the WO nanorods (NRs) scaffold, resulting in the well-defined Pd@DMAP/WO NRs heterostructures. The pinpointed deposition of Pd@DMAP on the WO NRs endows the Pd@DMAP/WO NRs heterostructure with conspicuously improved photoactivities for organic pollutant mineralization, as well as the capacities for photocatalytic selective oxidation of aromatic alcohols to aldehydes and photoreduction of chromium ions under the irradiation of simulated sunlight and visible light, far surpassing the applicability of blank WO NRs.

Self-transformation of ultra-small gold nanoclusters to gold nanocrystals toward boosted photoreduction catalysis.

Glutathione-protected Aux nanoclusters uniformly and intimately embedded at the interface of CdSe QDs and graphene were in situ self-transformed to Au nanocrystals (NCs) via a facile thermal reduction strategy. The inlaid Au NPs substantially accelerate the interfacial directional charge transfer toward multifarious photoreduction catalysis under visible light irradiation.

Comparison of gene expression profiles in BALB/c 3T3 transformed foci exposed to tumor promoting agents.

Identification of specific etiological carcinogens is one of the most important issues in environmental-toxicology studies. In this study, cDNA microarrays were used to analyze gene expression and discern chemical-associated profiles induced by a variety of tumor promoting agents in transformed cells. Two-stage transformation model of BALB/c 3T3 cells was established with MNNG as initiator, and 12-O-tetradecanoylphorbol-13-acetate (TPA), okadaic acid (OA), or cadmium chloride (CdCl(2)) as tumor promoters.

Evidence for conformational movement and radical mechanism in the reaction of 4-thia-L-lysine with lysine 5,6-aminomutase.

We demonstrate that the steady state reaction of lysine 5,6-aminomutase with substrate analogue 4-thia-l-lysine generates a radical intermediate, which accumulates in the enzyme to an electron paramagnetic resonance (EPR) detectable level. EPR line width narrowing of approximately 1 mT due to [4'-(2)H] labeling of the pyridoxal-5'-phosphate (PLP), an isotropic hyperfine coupling of 40 MHz for the proton at C4' of PLP derived from (2)H electron nuclear double resonance (ENDOR) measurement, and spin density delocalization onto the (31)P of PLP realized from observations of the (31)P ENDOR signal provide unequivocal identification of the radical as a substrate-PLP-based species. X- and Q-band EPR spectra fittings demonstrate that this radical is spin coupled with the low spin Co(2+) in cob (II) alamin and the distance between the two species is about 10 A.

[Clinical implication of blood somatostatin determination in critically ill patients].

Objective: To investigate the relationship between contents of blood somatostatin (SST) and inflammatory reaction or severity of illness in critically ill patients, and its value in the evaluation of prognosis.

Methods: Sixty critically ill patients were divided into three groups according to the acute physiology and chronic health evaluation II (APACHE II) score as mild (<16, 23 cases), mediate (16 - 20, 20 cases) and severe (>20, 17 cases) group; and also divided as dead (D, 13 cases) or survival group (S, 47 cases) according to the final outcome; 20 healthy volunteers served as control. The blood SST concentration was detected by radioimmunoassay, while the levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were measured by enzyme linked immunosorbent assay (ELISA).

Preoperative growth inhibition of human gastric adenocarcinoma treated with a combination of celecoxib and octreotide.

Aim: To gain insight into the histopathological responses and molecular targets in the inhibition of growth of human gastric cancer treated with celecoxib (a cyclooxygenase [COX]-2 inhibitor) combined with octreotide.

Methods: Seventy five patients with gastric cancer undergoing curative gastrectomy or extended resection were randomly divided into 3 groups. The apoptosis of tumor cells was measured by terminal deoxynucleotide transferase-mediated dUTP nick endlabeling (TUNEL) assay.

Differential expression of genes associated with cell proliferation and apoptosis induced by okadaic acid during the transformation process of BALB/c 3T3 cells.

Okadaic acid (OA) is a tumor promoter in two-stage carcinogenesis experiments. Nevertheless, the effects of OA on cell transformation, cell proliferation and apoptosis vary widely, and the molecular events underlying these effects of OA are not well understood. In the present study, we examined the promoting activity and the associated effects on cell growth and apoptosis mediated by OA in BALB/c 3T3 cells, and evaluated alterations of gene transcriptional expression by microarray analysis.

[Changes of vasoactive intestinal polypeptide and vasoactive intestinal polypeptide receptor 1 in small intestine and liver during macaque development].

The present study was aimed to investigate the changes of vasoactive intestinal polypeptide (VIP) and VIP receptor 1 (VIPR1) in small intestinal and hepatic tissues during macaque development. The tissue samples of small intestine, liver and blood samples from peripheral and portal vein of 4 macaques of 6-month fetus, 2-day neonate, 45-day neonate and adult were obtained after anesthetization. The concentration of VIP in blood or tissues of macaques was measured by radioimmunoassay.

[The inhibitive effects of celecoxib combined with octreotide on the metastasis of human gastric cancer in vivo].

Objective: To investigated if cyclooxygenase-2 (COX-2) inhibitor celecoxib in combination with somatostatin (SST) analog octreotide is able to inhibit the metastasis of human gastric cancer (GC) in vivo.

Methods: Seventy five patients with GC were randomly divided into 3 equal groups: control group, taking no anti-tumor medicine before GC resection; celecoxib group, receiving celecoxib orally 200 mg/d for 7 days before surgery; and combination group, receiving celecoxib orally 200 mg/d and octreotide 100 microg injected subcutaneously for 7 days before operation. The resected specimens were studied for the expression of epithelial cadherin (E-Cad) and matrix metalloproteinase (MMP) by using immunohistochemical staining.

[Initial research for effects of vasoactive intestinal polypeptide (VIP) on differentiation of human umbilical cord blood derived CD34+ cells into hepatic related cells].

Objective: To investigate the effect of vasoactive intestinal polypeptide (VIP) on differentiation of hematopoietic stem cells (HSC) into hepatic related cells and probe into the possibility that VIP affects HSC transdifferentiation.

Methods: Mini MACS assay was used to purify human CD34+ cells from mononuclear cell (MNC), the purity of the CD34+ cells was evaluated by flow cytometry. Alpha fetal proteins(AFP) in cultured CD34+ cells and their supernatant were measured with ELISA assay.

[Effects of selective and non-selective cyclooxygenase-2 inhibitor on the growth of colon cancer cells].

Objective: To evaluate the effects of selective and non-selective cyclooxygenase-2 on the growth and apoptosis of colon cancer cell lines in vitro.

Methods: The proliferation of colon cancer cells was determined by MTT assay, and the cell cycle progression was analyzed by flow cytometric assay. Annexin V/PI staining in combination with flow cytometric assay was used to detect apoptosis induced by NSAIDs.

Detection of genetic homogeneity of Panax notoginseng cultivars by sequencing nuclear 18S rRNA and plastid matK genes.

The nuclear 18S rRNA and chloroplast MATK genes of 18 samples of Panax notoginseng and its processed material Sanqi (Radix Notoginseng) were analyzed. The two genes, regardless of cultivar origin, were found to be identical to genotype R1 and M1, respectively, of the published sequences (GenBank accession no. D85171 and AB027526).

[Therapeutic effect of somatostatin on acute respiratory distress syndrome in experimental rats].

Objective: This study was aimed to assess the effects of somatostatin (SST) and its analog Octreotide on the treatment of acute respiratory distress syndrome (ARDS) in rat model.

Methods: ARDS rat model was induced by administration of paraquat. After 24 hours oral administration of paraquat, three drugs (SST, Octreotide and dexamethasone at dosage of 1 mg/kg, 0.

[Changes of somatostatin and expression of somatostatin receptor in small intestine and liver tissues during macaque development].

Intestinal tract, which produces more than fifty kinds of gut peptides, is regarded as the largest endocrine organ. With regard to the gut peptides, a number of studies were focused on their structure, function and the roles in some diseases. The changes in output or distribution of gut peptides in the intestinal tract during development have been largely unknown.

Study of MMLV RT- binding with DNA using surface plasmon resonance biosensor.

Surface plasmon resonance biosensor technique was used to study the binding of Moloney murine leukemia virus reverse transcriptase without RNase H domain (MMLV RT-) with DNA in the absence and in the presence of inhibitors. Different DNA substrates, including single-stranded DNA (ssDNA), DNA template-primer (T-P) duplex and gapped DNA, were immobilized on the biosensor chip surface using streptavidin-biotin, and MMLV RT(-)-DNA binding kinetics were analyzed by different models. MMLV RT-; could bind with ssDNA and the binding was involved in conformation change.

[Gene expression profiles in early stage of BALB/c 3T3 cells' transformation promoted with 12-O-tetradecanoylphorbol-13-acetate].

Objective: To elucidate the potential molecular mechanism responsible for the early time of tumor promotion, gene expression profile was studied in the transformed BALB/c 3T3 cells induced by 12-O-tetradecanoylphorbol-13-acetate (TPA).

Methods: The two-stage cell transformation model was established by using the initiator of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and promoter of TPA. Cell proliferation was measured by trypan blue staining and cell cycle analysis was carried out by flow cytometry assay.

Molecular mechanism of granulocytic differentiation of human promyelocytic leukemia HL-60 cells induced by all-trans retinoic acid.

Aim: To elucidate the molecular mechanism of granulocytic differentiation of human promyelocytic leukemia HL-60 cells induced by all-trans-retinoic acid (ATRA).

Methods: Flow cytometry was used to determine the cell cycle changes of HL-60 cells upon ATRA treatment. Gene expression profiles of HL-60 cells induced by 1 mumol.