Proton-Coupled Electron Transfer upon Oxidation of Tyrosine in a De Novo Protein: Analysis of Proton Acceptor Candidates.

Redox-active residues, such as tyrosine and tryptophan, play important roles in a wide range of biological processes. The αY de novo protein, which is composed of three α helices and a tyrosine residue Y32, provides a platform for investigating the redox properties of tyrosine in a well-defined protein environment. Herein, the proton-coupled electron transfer (PCET) reaction that occurs upon oxidation of tyrosine in this model protein by a ruthenium photosensitizer is studied by using a vibronically nonadiabatic PCET theory that includes hydrogen tunneling and excited vibronic states.

Determination of Methamphetamine by High-Performance Liquid Chromatography in Odor-Adsorbent Material Used for Training Drug-Detection Animals.

The objective of the present report was to develop and validate a simple, sensitive, and selective analytical method for the determination of methamphetamine in an odor-adsorbent material (gauze) which was used to improve and standardize the training method used for drug-detection animals. High-performance liquid chromatography (HPLC) was performed using a Spherisorb ODS2 C18 column (200 mm × 4.6 mm, 5 μm), with a mobile phase consisting of a 0.

Design and synthesis of multivalent drug delivery system with CA IX inhibitors as ligands.

A multivalent ligand delivery system holds tremendous potential in the field of tumor-targeted drug delivery. It addresses the challenges posed by the low affinity between small molecule ligand receptors and the rapid metabolism of small molecule drug conjugates (SMDCs) in vivo. Notably, existing multivalent ligand systems have demonstrated significant anti-tumor activity in various tumor models.

Self-Immolated Nanoadjuvant for In Situ Vaccination Immunotherapy of Colorectal Cancer.

Vaccination immunotherapy has revolutionized cancer treatment modalities. Although the immunomodulatory adjuvant generally employs for potentiating vaccine response, systemic administration may drive immune-related side effects, even immune tolerance. Therefore, tunable immunoadjuvants are highly desirable to simultaneously stimulate the immune response and mitigate systemic toxicity.

Sodium propionate improves cognitive and memory function in mouse models of Alzheimer's disease.

This study was designed to explore whether sodium propionate (SP) alleviates cognitive damage in a mouse model of Alzheimer's disease (AD). We evaluated behavioral and biochemical aspects in an animal model of AD made by intracerebroventricular injection of Aβ peptide. Two-month-old ICR mice were treated with SP or normal saline for 21 days (control group, Aβ group, Aβ + SP50 mg/kg group, Aβ + SP100 mg/kg group, and Aβ + SP200 mg/kg group).

Engineered bioorthogonal POLY-PROTAC nanoparticles for tumour-specific protein degradation and precise cancer therapy.

PROteolysis TArgeting Chimeras (PROTACs) has been exploited to degrade putative protein targets. However, the antitumor performance of PROTACs is impaired by their insufficient tumour distribution. Herein, we present de novo designed polymeric PROTAC (POLY-PROTAC) nanotherapeutics for tumour-specific protein degradation.

Copackaging photosensitizer and PD-L1 siRNA in a nucleic acid nanogel for synergistic cancer photoimmunotherapy.

Packaging multiple drugs into a nanocarrier with rational design to achieve synergistic cancer therapy remains a challenge due to the intrinsically varied pharmacodynamics of therapeutic agents. Especially difficult is combining small-molecule drugs and macromolecular biologics. Here, we successfully graft pheophorbide A (PPA) photosensitizers on DNA backbone at predesigned phosphorothioate modification sites.

Efficacy and Safety of Immune Checkpoint Blockades in the Treatment of Ocular Melanoma: A Systematic Review and Meta-Analysis.

Aim: This meta-analysis aimed to compare the efficacy and safety of immune checkpoint blockade for the treatment of ocular melanoma.

Methods: We searched the PubMed, EMBASE, and Cochrane Library databases up to July 2021. Effect sizes (ESs) and corresponding 95% confidence intervals (CIs) were used to compare the outcomes.

Frontal-posterior functional imbalance and aberrant function developmental patterns in schizophrenia.

Schizophrenia (SZ) is a neurodevelopmental disorder. There remain significant gaps in understanding the neural trajectory across development in SZ. A major research focus is to clarify the developmental functional changes of SZ and to identify the specific timing, the specific brain regions, and the underlying mechanisms of brain alterations during SZ development.

Verification of a multi-function closed maze for the detection of affective disorder and spatial cognitive impairment in post-weaning socially isolated rats.

Objective: To verify a behavioral device for the detection of learning, memory, and affective disorders in post-weaning socially isolated rats.

Methods: We tested the behavioral changes in post-weaning socially isolated rats using a multi-function closed maze, a self-developed behavioral device, against the classical mood disorder detection method, the IntelliCage system and Morris water maze.

Results: In the multifunctional closed maze experiment, the spatial learning and memory ability of post-weaning socially isolated rats decreased, which was consistent with the results of the water maze and IntelliCage system.

Acidity-Activatable Dynamic Nanoparticles Boosting Ferroptotic Cell Death for Immunotherapy of Cancer.

Immunotherapy shows promising therapeutic potential for long-term tumor regression. However, current cancer immunotherapy displays a low response rate due to insufficient immunogenicity of the tumor cells. To address these challenges, herein, intracellular-acidity-activatable dynamic nanoparticles for eliciting immunogenicity by inducing ferroptosis of the tumor cells are engineered.

Formation of an unusual glutamine tautomer in a blue light using flavin photocycle characterizes the light-adapted state.

Blue light using flavin (BLUF) photoreceptor proteins are critical for many light-activated biological processes and are promising candidates for optogenetics because of their modular nature and long-range signaling capabilities. Although the photocycle of the Slr1694 BLUF domain has been characterized experimentally, the identity of the light-adapted state following photoexcitation of the bound flavin remains elusive. Herein hybrid quantum mechanical/molecular mechanical (QM/MM) molecular dynamics simulations of this photocycle provide a nonequilibrium dynamical picture of a possible mechanism for the formation of the light-adapted state.

Co-Prodrugs of 7-Ethyl-10-hydroxycamptothecin and Vorinostat with in Vitro Hydrolysis and Anticancer Effects.

7-Ethyl-10-hydroxycamptothecin (SN38) and vorinostat (SAHA) are quite promising combination therapy agents applied to the clinical treatment of cancer. In this study, we designed and synthesized a series of novel SN38-SAHA co-prodrugs, which were conjugated by four different amino acids including glycine, alanine, aminobutyric acid, and 6-aminocaproic acid. The hydrolytic reconversion rate to SN38 and SAHA critically depended on the carbon chain length, which were evaluated in PBS (pH 6.

Natural silibinin modulates amyloid precursor protein processing and amyloid-β protein clearance in APP/PS1 mice.

Silibinin has been shown to attenuate cognitive dysfunction and inhibit amyloid-beta (Aβ) aggregation in Alzheimer's disease (AD) models. However, the underlying mechanism by which silibinin improves cognition remains poorly understood. In this study, we investigated the effect of silibinin on β-secretase levels, Aβ enzymatic degradation, and oxidative stress in the brains of APP/PS1 mice with cognitive impairments.

Synthesis and biological evaluation of paclitaxel and vorinostat co-prodrugs for overcoming drug resistance in cancer therapy in vitro.

Paclitaxel (PTX) is the first-line treatment drug for breast cancer. However, drug resistance after a course of treatment and low selectivity restricted its clinical utility sometimes. In this study, we successfully bound PTX and vorinostat (SAHA) to form co-prodrugs based on the synergistic anticancer effects.

A series of camptothecin prodrugs exhibit HDAC inhibition activity.

Camptothecin plays an important role in clinical cancer treatment, and its derivatives are a favorite of pharmaceutical chemists. Herein, we have designed a series of camptothecin prodrugs that exhibit histone deacetylase (HDAC) inhibition activity based on the synergy effect between HDAC inhibitors and camptothecin derivatives. With the evaluation of stability in buffers or plasma from human or mouse model, an appropriate linker was found, so the active drug can be released efficiently and compound 21a exhibited strong antiproliferative activity in A549 and HCT-116 cell lines.

The impact of ALDH2 activation by Alda-1 on the expression of VEGF in the hippocampus of a rat model of post-MI depression.

Post-MI depression is a critical clinical problem, the comorbidity of which complicates depression treatment and worsens cardiovascular outcomes. However, which antidepressant is the best to lower the risk of cardiovascular events in persons with depression was still unknown. Recently, it has been proposed that the activation of ALDH2 by Alda-1 can effectively reduce depressive-like behaviors and improve the prognosis of coronary heart disease.

Maleimidation of dextran and the application in designing a dextran-camptothecin conjugate.

Camptothecin analogs, as commonly used chemotherapy drugs, usually have poor water solubility which has limited their use in the clinic. In order to improve the water-solubility of camptothecin, a new dextran derivative Dex-Mal was synthesized and used in designing a dextran-camptothecin conjugate which contained a CTB-sensitive linker. This conjugate could efficiently release the therapeutic drug SN-38 in the presence of cathepsin B and the antiproliferative activity of the conjugate was similar to the approved drug Irinotecan hydrochloride.

Neuron-derived CCL2 contributes to microglia activation and neurological decline in hepatic encephalopathy.

Background: CCL2 was up-regulated in neurons and involved in microglia activation and neurological decline in mice suffering from hepatic encephalopathy (HE). However, no data exist concerning the effect of neuron-derived CCL2 on microglia activation in vitro.

Methods: The rats were pretreated with CCL2 receptor inhibitors (INCB or C021, 1 mg/kg/day i.

Antioxidative and Anti-Apoptotic Roles of Silibinin in Reversing Learning and Memory Deficits in APP/PS1 Mice.

Silibinin has been widely used to treat liver diseases due to its antioxidant activity. However, the effects of silibinin on the central nervous system have not been thoroughly investigated. The pathological hallmarks of Alzheimer's disease are the accumulation of amyloid β protein, development of neurofibrillary tangles and increased oxidative stress, which ultimately lead to irreversible neuronal loss and cognitive impairment.

Synthesis and Biological Evaluation of Paclitaxel and Camptothecin Prodrugs on the Basis of 2-Nitroimidazole.

Due to the low esterase activity in human plasma, many ester and carbonate prodrugs tested in humans may be less effective than that in preclinical animals. In this letter, PTX and SN-38 were attached to the -1 position of 2-nitroimidazole via a carbonate linker. Presumably, 2-aminoimidazole may help promote the intramolecular hydrolysis of the carbonate bond.

Carbamoylmannose enhances the tumor targeting ability of supramolecular nanoparticles formed through host-guest complexation of a pair of homopolymers.

Conjugation of sugars to antitumor drugs can facilitate drug binding to tumor cells and the saccharide motifs of bleomycins (BLMs) play a crucial role in tumor-seeking. Here, we synthesized BLM monosaccharide, carbamoylmannose, and subsequently prepared carbamoylmannose decorated platinum-incorporating supramolecular nanoparticles formed through the host-guest complexation of poly(N-vinylpyrrolidone) and poly(aspartic acid). The targeting effects of carbamoylmannose decorated supramolecular nanoparticles in various cancer cells and tumor-bearing mice were investigated.

Targeting CCR3 to Reduce Amyloid-β Production, Tau Hyperphosphorylation, and Synaptic Loss in a Mouse Model of Alzheimer's Disease.

The majority of Alzheimer's disease (AD) patients have a late onset, and chronic neuroinflammation, characterized by glial activation and secretion of pro-inflammatory cytokines and chemokines, plays a role in the pathogenesis of AD. The chemokine CCL11 has been shown to be a causative factor of cognitive decline in the process of aging, but little is known whether it is involved in the pathogenesis of AD. In the present study, we showed that CCR3, the receptor for CCL11, was expressed by hippocampal neurons and treatment of primary hippocampal neuronal cultures (14 days in vitro) with CCL11 resulted in activation of cyclin-dependent kinase 5 and glycogen synthase kinase-3β, associated with elevated tau phosphorylation at multiple sites.

Insights into the structural, electronic and magnetic properties of V-doped copper clusters: comparison with pure copper clusters.

The structural, electronic and magnetic properties of Cun+1 and CunV (n = 1-12) clusters have been investigated by using density functional theory. The growth behaviors reveal that V atom in low-energy CunV isomer favors the most highly coordinated position and changes the geometry of the three-dimensional host clusters. The vibrational spectra are predicted and can be used to identify the ground state.