Molecular descriptors and fingerprints have been routinely used in QSAR/SAR analysis, virtual drug screening, compound search/ranking, drug ADME/T prediction and other drug discovery processes. Since the calculation of such quantitative representations of molecules may require substantial computational skills and efforts, several tools have been previously developed to make an attempt to ease the process. However, there are still several hurdles for users to overcome to fully harness the power of these tools. First, most of the tools are distributed as standalone software or packages that require necessary configuration or programming efforts of users. Second, many of the tools can only calculate a subset of molecular descriptors, and the results from multiple tools need to be manually merged to generate a comprehensive set of descriptors. Third, some packages only provide application programming interfaces and are implemented in different computer languages, which pose additional challenges to the integration of these tools. A freely available web-based platform, named ChemDes, is developed in this study. It integrates multiple state-of-the-art packages (i.e., Pybel, CDK, RDKit, BlueDesc, Chemopy, PaDEL and jCompoundMapper) for computing molecular descriptors and fingerprints. ChemDes not only provides friendly web interfaces to relieve users from burdensome programming work, but also offers three useful and convenient auxiliary tools for format converting, MOPAC optimization and fingerprint similarity calculation. Currently, ChemDes has the capability of computing 3679 molecular descriptors and 59 types of molecular fingerprints. ChemDes provides users an integrated and friendly tool to calculate various molecular descriptors and fingerprints. It is freely available at http://www.scbdd.com/chemdes . The source code of the project is also available as a supplementary file.
Apoptosis, or programmed cell death, is involved in numerous human conditions including neurodegenerative diseases, ischemic damage, autoimmune disorders and many types of cancer, and is often confused with other types of cell death. Therefore strategies that enable visualized detection of apoptosis would be of enormous benefit in the clinic for diagnosis, patient management, and development of new therapies. In recent years, improved understanding of the apoptotic machinery and progress in imaging modalities have provided opportunities for researchers to formulate microscopic and macroscopic imaging strategies based on well-defined molecular markers and/or physiological features. Correspondingly, a large collection of apoptosis imaging probes and approaches have been documented in preclinical and clinical studies. In this review, we mainly discuss microscopic imaging assays and macroscopic imaging probes, ranging in complexity from simple attachments of reporter moieties to proteins that interact with apoptotic biomarkers, to rationally designed probes that target biochemical changes. Their clinical translation will also be our focus.
The development of imageable photothermal theranostics has attracted considerable attention for imaging guided photothermal therapy (PTT) with high tumor ablation accuracy. In this study, we strategically constructed a near-infrared (NIR) cyanine dye by introducing a rigid cyclohexenyl ring to the heptamethine chain to obtain a heptamethine dye CySCOOH with high fluorescence intensity and good stability. By covalent conjugation of CySCOOH onto human serum albumin (HSA), the as-prepared HSA@CySCOOH nanoplatform is highly efficient for NIR fluorescence/photoacoustic/thermal multimodality imaging and photothermal tumor ablation. The theranostic capability of HSA@CySCOOH was systematically evaluated both in vitro and in vivo. Most intriguingly, complete tumor elimination was achieved by intravenous injection of HSA@CySCOOH (CySCOOH, 1 mg kg−1; 808 nm, 1.0 W cm−2 for 5 min) into 4T1 tumor-bearing mice, with no weight loss, noticeable toxicity, or tumor recurrence being observed. This as-prepared protein-based nanotheranostics exhibits high water dispersibility, no off target cytotoxicity, and good biodegradability and biocompatibility, thus facilitating its clinical translation to cancer photothermal theranostics.
Magnesium ions (Mg2+) play essential roles in various physiological and pathological processes, its abnormal homeostasis in cells is related to many diseases, such as diabetes, neuromuscular disorders, hypertension and other cardiovascular disorders. Investigation on the regulation of magnesium in cellular processes has attracted considerable interest in the past several decades. Among those reported strategies, fluorescent imaging technology has become a powerful and cost-effective tool for the real-time monitoring of magnesium distribution, uptake and trafficking, due to its superior features of high sensitivity and non-invasiveness, as well as excellent spatial and temporal fidelity. Herein, we critically summarize the progresses in the intracellular magnesium detection with fluorescent imaging probes. Our discussion focuses on the recent contributions concerning fluorescent imaging probes for mapping magnesium in biological processes. All the candidates are organized according to their acceptor structures. The sensing mechanisms of fluorescent probes are also highly taken into account. Challenges, trends and prospects of fluorescent imaging technology in magnesium detection are also set forth.
Bacterial biofilm-associated infection was one of the most serious threats to human health. However, effective drugs for drug-resistance bacteria or biofilms remain rarely reported. Here, we propose an innovative strategy to develop a multifunctional antimicrobial agent with broad-spectrum antibacterial activity by coupling photosensitizers (PSs) with antimicrobial peptides (AMPs). This strategy capitalizes on the ability of PSs to generate reactive oxygen species (ROS) and the membrane-targeting property of AMPs (KRWWKWIRW, a peptide screened by an artificial neural network), synergistically enhancing the antimicrobial activity. In addition, unlike conventional aggregation-caused quenching (ACQ) photosensitizers, aggregation-induced emission (AIE) PSs show stronger fluorescence emission in the aggregated state to help visualize the antibacterial mechanism. In vitro antibacterial experiments demonstrated the excellent killing effects of the developed agent against both Gram-positive (G+) and Gram-negative (G–) bacteria. The bacterial-aggregations induced ability enhanced the photoactivatable antibacterial activity against G– bacteria. Notably, it exhibited a significant effect on destroying MRSA biofilms. Moreover, it also showed remarkable efficacy in treating wound infections in mice in vivo. This multifunctional antimicrobial agent holds significant potential in addressing the challenges posed by bacterial biofilm-associated infections and drug-resistant bacteria.