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Catechol estrogens (CEs) are known to be toxic metabolites and the initiators of the oncogenesis of breast cancers via forming covalent adducts with DNAs. CEs shall also react with proteins, but their cellular protein targets remain unexplored. Here, we reported the identification of protein targets of CEs in the soluble cytosol of estrogen-sensitive breast cancer cells by multiple comparative proteomics using liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with an improved click chemistry-based workflow. Multiple comparative proteomics composed of an experimental pair (probe versus solvent) and two control pairs (solvent versus solvent and probe versus solvent without enrichment) were studied using stable isotope dimethyl labeling. The use of 4-hydroxyethynylestradiol (4OHEE2) probe with an amide-free linker coupled with on-bead digestion and redigestion of the proteins cleaved from the beads was shown to greatly improve the recovery and identification of CE-adducted peptides. A total of 310 protein targets and 40 adduction sites were repeatedly (n ≥ 2) identified with D/H (probe/solvent) ratio >4 versus only one identified with D/H >4 from the two control pairs, suggesting that our workflow imposes only a very low background. Meanwhile, multiple comparative D/H ratios revealed that CEs may downregulate many target proteins involved in the metabolism or detoxification, suggesting a negative correlation between CE-induced adduction and expression of proteins acting on the alleviation of stress-induced cellular damages. The reported method and data will provide opportunities to study the progression of estrogen metabolism-derived diseases and biomarkers.Monitoring chemical reactions that occur in small spaces or confined environments is challenging. Surface-enhanced Raman scattering (SERS) spectroscopy offers the unique possibility to monitor spectral changes with high sensitivity and time resolution. Herein, we report the application of composite mesoporous TiO2 films loaded with Ag nanoparticles (NPs) to track in situ chemical processes in real time. In particular, the AgNPs@TiO2 system was employed to monitor two chemical reactions one occurring on the Ag NPs surface and another taking place in the surrounding solution. In the first case, we monitored the decarboxylation reaction of 4-mercaptobenzoic acid on Ag NPs, which allowed us to identify the conditions that favor it. In the second case, we studied the pH evolution in the nanocavities during a homogeneous alkalization process driven by chloride-assisted glycidol rupture (the Epoxide Route) and compared it with pH measurements by conventional techniques. We therefore demonstrated that the proposed nanodevice provides an excellent performance to monitor dynamic processes occurring either inside the material or in the solution in which it is immersed.Glycomaterials display enhanced binding affinity to carbohydrate-binding proteins due to the nonlinear enhancement associated with the cluster glycoside effect. Gold nanoparticles bearing glycans have attracted significant interest in particular. This is due to their versatility, their highly tunable gold cores (size and shape), and their application in biosensors and diagnostic tools. However, conjugating glycans onto these materials can be challenging, necessitating either multiple protecting group manipulations or the use of only simple glycans. This results in limited structural diversity compared to glycoarrays which can include hundreds of glycans. Here we report a method to generate glyconanoparticles from unprotected glycans by conjugation to polymer tethers bearing terminal amino-oxy groups, which are then immobilized onto gold nanoparticles. Using an isotope-labeled glycan, the efficiency of this reaction was probed in detail to confirm conjugation, with 25% of end-groups being functionalized, predominantly in the ring-closed form. Facile post-glycosylation purification is achieved by simple centrifugation/washing cycles to remove excess glycan and polymer. This streamlined synthetic approach may be particularly useful for the preparation of glyconanoparticle libraries using automation, to identify hits to be taken forward using more conventional synthetic methods. Exemplar lectin-binding studies were undertaken to confirm the availability of the glycans for binding and show this is a powerful tool for rapid assessment of multivalent glycan binding.Current strategies to construct cell-based bioartificial tissues largely remain on a multicell level. Taking cell diversity into account, single-cell manipulation is urgently needed for delicate bioartificial tissue construction. Current single-cell isolation and profiling techniques involve invasive processes and thus are not applicable for single-cell manipulation. Here, we managed to fabricate peptide-liquid metal hybrid hydrogels as “cell ambers” which were suitable for single-cell isolation as well as further handling. The successful preparation of uniform liquid metal nanoparticles allowed the fabrication of peptide-liquid metal hydrogel with excellent recovery property upon mechanical destruction. The alkaline phosphatase-instructed supramolecular self-assembly process allowed the formation of microhydrogel post-filling in the PDMS template. The co-culture of the hydrogel precursor and mammalian cells realized the embedding of cells into elastic hydrogels which were the so-called cell ambers. PF-03084014 The cell ambers turned out to be biocompatible and capable of supporting cell survival. Aided with the micro-operating system and a laser scanning confocal microscope, we could arrange these as-prepared 3D single-cell ambers into various patterns as desired. Our strategy provided the possibility to manipulate a single cell, which served as a prototype of cell architecture toward cell-based bioartificial tissue construction.

Previous studies have reported the pain-relieving effect of chronic electrical motor cortex stimulation (eMCS) in various types of neuropathic pain.

The study aimed to explore the potential relationship between the clinical efficacy of eMCS for the treatment of chronic neuropathic pain and the precise localization of the contacts over the motor cortex somatotopic representation of the painful area.

A total of 22 patients with neuropathic pain were implanted with eMCS electrodes. Implantation of the electrodes was performed using intraoperative 1) anatomical identification by neuronavigation software using 3D-MRI; 2) monitoring of somesthetic evoked potentials to check the potential reverse over the central sulcus; and 3) electrical stimulations through the dura to identify the motor responses and its somatotopy. Image fusion of postoperative 3D-CT and preoperative MRI images allowed postoperative location of the electrodes.

Analgesic effects were obtained in 18 (81.81%) out of 22 patients. Postoperative 3D-CT analysis showed a correspondence between localization of the contacts and the motor cerebral cortex somatotopy in the patients with postoperative good analgesic effects.