K48-Linked Ubiquitination Contributes to Nicotine-Augmented Bone Marrow-Derived Dendritic-Cell-Mediated Adaptive Immunity.

K48-linked ubiquitination determining antigen degradation and the endosomal recruitments of p97 and Sec61 plays vital roles in dendritic cell (DC) cross-presentation. Our previous studies revealed that nicotine treatment increases bone marrow-derived dendritic cell (BM-DC) cross-presentation and promotes BM-DC-based cytotoxic T lymphocyte (CTL) priming. But the effect of nicotine on K48-linked ubiquitination and the mechanism of nicotine-increased BM-DC cross-presentation are still uncertain.

Synthesis and chelation study of a fluoroionophore and a glycopeptide based on an aza crown iminosugar structure.

Capitalizing on a recently reported iminosugar-based aza-crown (ISAC) accessed by a double Staudinger azaWittig coupling reaction, we have expanded the structural diversity of this new family of sweet cyclam analogs. Replacement of the two secondary amines linking the iminosugar units by two amide bonds obtained a cyclodimerization by with BOP and DIPEA led to a macrocycle that did not demonstrate efficient Zn chelation unlike the parent ISAC. Introduction of two pyrene moieties on the secondary amines of the parent ISAC yielded a new fluoroionophore that selectively binds Hg in methanol.

Aggregation-induced emission enhancement upon Al3+ complexation with a tetrasulfonated calix[4]bisazacrown fluorescent molecular sensor.

Aggregation-induced emission and aggregation-induced emission enhancement have attracted much attention due to their great potential in real-world applications. Up to now most of the reports are based on the restriction of free rotation of the luminogens in the aggregates. In the present work, we found that the dansyl fluorophore with typical intramolecular charge transfer characteristic also exhibited aggregation-induced emission enhancement, which was based on the change of micro-environmental polarity of the fluorophore.

Hg2+-promoted photoactivation of triazolyl rhodamine.

Hg(2+) was able to induce the ring-opening of glycosyl triazolyl rhodamines after 26 h incubation at room temperature in MeCN-DMSO (99 : 1). This reaction can be dramatically accelerated by irradiation at 313 nm, by reducing the response time to 2 min. Selectivity towards Hg(2+) has also been demonstrated, except for Cu(2+), other metal ions showed almost no influence on this photochromic process.

Isolable chiral aggregates of achiral π-conjugated carboxylic acids.

The induced aggregation of achiral building blocks by a chiral species to form chiral aggregates with memorized chirality has been observed for a number of systems. However, chiral memory in isolated aggregates of achiral building blocks remains rare. One possible reason for this discrepancy could be that not much is understood in terms of designing these chiral aggregates.

Supramolecular aggregation/disaggregation-based molecular sensing: a review focused on investigations from China.

Supramolecular aggregation and disaggregation induced by external stimuli can impact the optical or electrical signals of the aggregates/constituting units (receptors). Therefore, manipulating supramolecular aggregation/disaggregation has recently been employed to construct novel and promising photoluminescence (PL)-based sensing and recognition systems. The sensing systems were capable of substantially enhancing the sensitivity, relying on cooperative interactions occurring in the assembly/disassembly processes (mostly operating in emission turned-on or emission-enhanced mode).

A ratiometric luminescent sensing of Ag+ ion via in situ formation of coordination polymers.

A ratiometric luminescent sensing of Ag(+) ion is developed via the Ag(I)-NCys coordination polymeric luminophore in situ formed in aqueous solution upon mixing Ag(+) ion with the designed fluorescent thiol ligand NCys.

Highly sensitive naked-eye and fluorescence "turn-on" detection of Cu(2+) using Fenton reaction assisted signal amplification.

Increase of pH induced by Cu(2+)-catalyzed Fenton reaction promoted ring-opening of triazole-linked fluorescein lactone, which enabled selective "turn-on" fluorescent detection of Cu(2+), along with ultralow naked-eye detection limit down to 200 nM.

Specific Hg(2+)-mediated perylene bisimide aggregation for highly sensitive detection of cysteine.

Hg(2+) was found to specifically induce the aggregation of perylene bisimide in a "thymine-Hg(2+)-thymine" binding motif and the resultant aggregates showed a highly selective and sensitive turn-on fluorescence response for cysteine, with a detection limit down to 9.6 nM.

Enhanced saccharide sensing based on simple phenylboronic acid receptor by coupling to Suzuki homocoupling reaction.

Substantially enhanced monosaccharide fluorescent sensing in aqueous solutions using a simple phenylboronic acid receptor is achieved by coupling the classic strategy based on saccharide-boronic acid interaction with catalytic Suzuki homocoupling reaction.

Molecular logic gates and switches based on 1,3,4-oxadiazoles triggered by metal ions.

Organic molecular devices for information processing applications are highly useful building blocks for constructing molecular-level machines. The development of "intelligent" molecules capable of performing logic operations would enable molecular-level devices and machines to be created. We designed a series of 2,5-diaryl-1,3,4-oxadiazoles bearing a 2-(para-substituted)phenyl and a 5-(o-pyridyl) group (substituent X=NMe(2), OEt, Me, H, and Cl; 1a-e) that form a bidentate chelating environment for metal ions.

N-(Acetamido)thiourea based simple neutral hydrogen-bonding receptors for anions.

N-(Acetamido)-N'-phenylthioureas (4-6) were found to be efficient anion receptors with higher anion affinity than their N-benzamido-N'-phenylthiourea counterparts (1 and 2). The N'-phenylthiourea moiety in 4-6 was shown to be the chromophore with an absorption maximum at ca. 270 nm.

Oxidative cyclization of N-acylhydrazones. Development of highly selective turn-on fluorescent chemodosimeters for Cu2+.

A series of N-acylhydrazones were synthesised and found to be "turn-on" fluorescent chemodosimeters for Cu(2+). Among the tested transition metal ions such as Cu(2+), Pb(2+), Zn(2+), Cd(2+), Hg(2+), and Ni(2+), a prominent fluorescence enhancement of up to 1000-fold was only observed for Cu(2+) in acetonitrile (CH(3)CN). This was indicated by an onset of unprecedented structured emission.