Latest ArticlesDespite the rapid development of fluorescence detection modalities for disease diagnosis, novel fluorescent molecules and probes still face with tremendous pressure to transform before employing such fluorescent tools in the clinic. Impressively, the fluorescent probes based on the traditional fluorescent dye are expected to accelerate the transformation process. Herein, methylene blue is requisitioned to design the GSH responsive probe MB-SS-CPT elaborately. The as-synthesized MB-SS-CPT provides a dramatic optical advantage for GSH detection in vitro, cell fluorescence imaging, in vivo imaging, and antitumor therapy.
Three novel dithienylethenes modified by bifluoroboron β-diketonate fragments have been successfully developed. Upon blue light irradiation, they reached photostationary state within 2–5 s, as well as 100% conversion ratio and photocyclization quantum yield of > 0.70. Such fascinating photochromism were endowed by collaborative role of electron-withdrawing effect of BF2bdk group to reduce HOMO-LUMO electronic gap for the open isomer, together with intramolecular hydrogen bonds and CH-π interactions favoring antiparallel conformation fixation. Moreover, they displayed specific discrimination and photoswitchable bacterial imaging for S. aureus.
HIV-1 capsid protein (CA) has emerged as a promising target for antiviral treatment considering its structural and regulatory roles in HIV-1 replication. Here, we disclose the design, synthesis, biological assessment, and mechanism investigation of a novel series of phenylalanine derivatives gained by further structural modification of PF74. The newly synthesized compounds demonstrated potent anti-HIV activity, represented by 7n displayed anti-HIV-1 activity 6.25-fold better than PF74, and 7h showed anti-HIV-2 activity with nearly 139 times improved efficacy over PF74. Surface plasmon resonance (SPR) studies of representative compounds proved that HIV-1 CA was the binding target. Competitive SPR studies using CPSF6 and NUP153 peptides identified that 7n binds to a vital CA assembly interface between the N-terminal and C-terminal domain (NTD-CTD interface). Action stage determination assay revealed that the newly synthesized compounds were antiviral with a dual-stage inhibitory profile. Molecular dynamics (MD) simulations offered the crucial foundation for the hopeful antiviral potency of 7n. Besides, 7m and 7n modestly increased metabolic stabilities in human liver microsome (HLM) and human plasma compared to PF74. Overall, these studies offer valuable insights and can regard as the beginning for succedent medicinal chemistry endeavors to discover promising HIV capsid inhibitors with improved efficacy and better drug-like characteristics.
Liposomes have been widely exploited as a drug delivery system in treating tumors because of their advantage to enhance anti-tumor efficacy and reduce side effects. In this study, the tumor-targeted 2-dodecyl-6-methoxycyclohexa-2, 5-diene-1, 4-dione (DMDD, i.e., Averrhoa carambola extractive) liposomes (HA/TN-DLP) were conducted and assessed. HA/TN-DLP showed controllable drug loading (up to 83%) with high stability. In vitro and in vivo studies showed good cell uptake behavior and high inhibition rate of breast cancer compared to free DMDD. HA/TN-DLP might be the suitable for DMDD due to its better advantages in delivery, penetrability, and targeting-tumor capability. For in vivo mouse model tests, HA/TN-DLP effectively inhibited tumor growth compared to free DMDD. Further analyses indicated that HA/TN-DLP inhibited the glycerophospholipid metabolism pathway by reducing the biosynthesis of phosphatidylcholine and 1-acyl-sn-glycero-3-phosphocholine through regulating the expressions of CEPT1 and LYPLA1, and inhibited tumor cell growth by regulating the PI3K/Akt and NF-κB signaling pathways. In conclusion, the obviously enhanced antitumor effect further demonstrated that HA/TN-DLP may be a promising tumor-targeting agent.
It is cellular immunotherapy for the tumor that the in vitro modified immunocytes from patients or donors are reinfused into patients to kill tumor cells. Chimeric antigen receptor T cell (CAR-T) therapy, one of the most successful and representative tumor cellular immunotherapies, is now the weapon for cancer after extensive research. Although CAR-T immunotherapy achieves success in treating relapsed/refractory hematological tumors, its drawbacks, including the poor effect in solid tumors, cytokine release syndrome (CRS) or CAR-T-related encephalopathy syndrome (CRES), on-target, off-tumor effect, and high cost, cannot be overlooked. Nanotechnology is advantageous in the construction of CARs, the transfection of T cells, the expansion, delivery, and antitumor effect of CAR-T cells, and the reduction of CAR-T therapy-associated toxicities. Currently, introducing nanotechnology into CAR-T immunotherapy has already been performed in numerous studies with highly promising results. In this review, we summarized the nanotechnologies used in CAR-T immunotherapy and discussed the challenges and directions of CAR-T immunotherapy combined with nanotechnologies in the future.
Catalytic asymmetric dearomatization of indoles and alkynes has received much attention in the past decade because this strategy offers an attractive and alternative way for the efficient synthesis of valuable chiral polycyclic indolines. However, these reactions have been mostly limited to transition-metal catalysts, and the related chiral Brønsted acid catalysis has been scarcely reported. Herein, we disclose a chiral phosphoric acid-catalyzed asymmetric dearomatization of indolyl ynamides by direct activation of alkynes. This metal-free method enables the practical and atom-economical construction of an array of valuable chiral polycyclic indolines in moderate to good yields with high enantioselectivities
It is of great significance to construct organic circularly polarized luminescence systems (CPL) with large luminescence dissymmetry factors (glum) for practical applications. Here we report organic CPL systems constructed by merging triplet-triplet annihilation upconversion chromophores in cellulose matrices. The chirality of the matrix is transferred to the achiral chromophores of photon upconversion and then the multistep energy transfer processes of upconversion amplify glum. The glum value of upconversion CPL in the left-handed ethyl cellulose and the right-handed (acetyl) ethyl cellulose are up to +0.1 and −0.15, respectively. The study provides a straightforward approach for constructing solid organic upconversion CPL materials with large glum, which may expand the application potentials of organic chiroptical materials.
In recent years, nanozymes have received more and more attention, but the low activity limits the development of nanozymes. Therefore, the design and development of efficient nanozymes is still a major challenge for researchers. Herein, the Fe,N co-doped ultrathin hollow carbon framework (Fe,N-UHCF) exhibit ultra-high peroxidase-like activity. The specific activity of Fe,N-UHCF nanozyme is as high as 36.6 U/mg, which is much higher than almost all of other reported nanozymes. In practical applications, the Fe,N-UHCF show good antibacterial effects.
The normal operation of lysosome, mitochondria, Golgi apparatus and endoplasmic reticulum plays a significant role in maintaining cell homeostasis. Reflecting the state and function of lysosomes, viscosity is a pivotal parameter to assess the stability of microenvironment. Herein, based on TICT mechanism, a new NIR pH-dependent fluorescent probe DCIC with push-pull electronic moiety was synthesized to identify the lysosomes viscosity. In viscous media, DCIC was highly sensitive to viscosity, fluorescence intensity increased by 180 times as viscosity increased from 1.0 cp to 438.4 cp. In addition, DCIC have high localization ability for lysosome, mitochondria, Golgi apparatus, and endoplasmic reticulum and can monitor lysosomal viscosity fluctuations with laser confocal microscopy.
Aiming at the construction of novel rotaxanes with desired luminescent properties for practical applications, recently the rapid development of rotaxanes decorated with aggregation-induced emission (AIE) luminogens (i.e., AIEgens) has been witnessed. The combination of AIEgens and rotaxanes leads to the successful construction of a novel type of luminescent rotaxanes with many attractive features. In particular, the unique controllable dynamic feature of rotaxanes endows the resultant AIEgen-based rotaxanes precisely tunable emissions under external stimuli, leading to the construction of a novel type of smart luminescent materials. In this minireview, the recent progress of AIEgen-based rotaxanes has been summarized, with an emphasis on the design strategy and potential applications.