Latest ArticlesA chronic liver disease usually results in iron accumulation, and an excess of iron will further aggravate liver injury, forming a vicious circle. Likewise, it also plays a significant role in other organs when it comes to iron metabolism. A long time passes between the time it takes to break through to MRI-based iron diagnosis and its ability to distinguish the types of iron accumulation accurately and quickly. This work highlighted a new type of iron accumulation treatment solution integrated with diagnosis and treatment. A chelating method for ICG and Leci that can assist PAI and MRI to achieve better diagnostic and therapeutic effects. This work revealed biomaterial engineering techniques are being adapted to address clinical medical problems through cutting-edge research.
Heteroatom-doped porous carbon materials are very attractive for lithium ion batteries (LIBs) owing to their high specific surface areas, open pore structures, and abundant active sites. However, heteroatom-doped porous carbon with very high surface area and large pore volume are highly desirable but still remain a big challenge. Herein, we reported a sulfur-doped mesoporous carbon (CMK-5-S) with nanotubes array structure, ultrahigh specific surface area (1390 m2/g), large pore volume (1.8 cm3/g), bimodal pore size distribution (2.9 and 4.6 nm), and high sulfur content (2.5 at%). The CMK-5-S used as an anode material for LIBs displays high specific capacity, excellent rate capability and highly cycling stability. The initial reversible specific capacity at 0.1 A/g is as high as 1580 mAh/g and simultaneously up to 701 mAh/g at 1 A/g even after 500 cycles. Further analysis reveals that the excellent electrochemical storage performances is attributed to its unique structures as well as the expanded lattice by sulfur-doping.
Covalent organic frameworks (COFs), as highly tunable porous crystalline materials, have promising applications in potassium-ion batteries (PIBs) due to their abundant charge carrier transport channels and excellent structural stability. However, the excessive stacking of interlayer electron clouds makes it difficult to expose internal active sites. Strategies to design functional COFs with controllable morphology and copious active sites are promising but still challenging. Herein, by utilizing the condensation between 1,3,5-triformylbenzene (TFB) and p-phenylenediamine (PPD) and using amino-modified SiO2 nanospheres as templates, we synthesize core-shell NH2-SiO2@TP-COF. Through NaOH etching of NH2-SiO2@TP-COF, we obtain imine-based TP-COF hollow nanospheres, which shows excellent potassium storage performance when applied to the anode for PIBs. Ex-situ analysis and density functional theory calculations reveal that CN groups and benzenes are active sites for K+ storage.
Suspension cells play a crucial role in many biological processes. However, compared to adherent cells, it is particularly challenging to introduce exogenous genes into suspension cells to regulate their biological functions with non-viral gene vectors, mainly due to the low cellular uptake and endosomal escape of polyplexes. Herein, to improve the interactions of polyplexes with cellular membranes, we design and synthesize highly branched poly(β-amino ester) (HPAE) via an "A2 + B4 + C2" Michael addition strategy. Results show that branching significantly increases DNA condensation of HPAE, cellular uptake and endosomal escape of HPAE/DNA polyplexes. In mast cells (MCs), HPAE exhibits up to 80-fold higher gene transfection efficiency compared to the corresponding linear poly(β-amino ester) (LPAE) and the leading commercial gene transfection reagents PEI25k, jetPEI, and Lipofectamine 3000, without causing obvious cytotoxicity. Our study establishes a reliable non-viral platform for efficient gene transfection of suspension cells.
Accumulating evidence in recent years indicates that DNA methylation (5-methyl-2′-deoxycytidine, 5-mdC) and hydroxymethylation (5-hydroxymethyl-2′-deoxycytidine, 5-hmdC) have been implicated in various biological processes, and the aberrations of these DNA cytosine modifications is tightly associated with cancer. N6-methyl-2′-deoxyadenosine (m6dA), as a newly discovered epigenetic modification in genome of mammals, has been demonstrated to play vital regulatory roles in tumorigenesis. However, the content information of m6dA in human tumor tissues is still limited and pan-cancer analysis of these DNA epigenetic modifications is lacked. Herein, we developed a sensitive and robust stable isotope-diluted hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC-MS/MS) method for accurate quantification of m6dA, 5-mdC and 5-hmdC in genomic DNA from 82 pairs of human tumor tissues and matched tumor-adjacent normal tissues. The types of tumors included esophagus cancer, lung cancer, breast cancer, liver cancer, pancreatic cancer, gastric cancer, stromal tumor and colorectal cancer. Compared to the normal tissues, we revealed the level of m6dA was increased in tumor tissues of esophagus cancer, lung cancer and liver cancer, whereas the level of m6dA was diminished in tumor tissues of pancreatic cancer and gastric cancer; while the contents of 5-mdC and 5-hmdC exhibited significant decrease in tumor tissues of most types of cancer. It is worth noting that we revealed, for the first time, the content of genomic m6dA in pancreatic cancer, stromal tumor and colorectal cancer. The significant changes of these DNA epigenetic modifications indicate they may serve as indicators of cancers. In addition, this study will benefit for better understanding of the regulatory roles of these DNA epigenetic modifications in cancers.
Due to the increasing demand for the sustainability of modern organic chemistry, the development of green and powerful methods for C-C and C-B bond formation is highly desired. Among them, the transition-metal-free coupling reactions of gem–diborylalkanes emerge as one valuable tool for organic chemists in the last decade. The review covers selected representative examples. A comparison of these reactions with transition-metal-catalyzed reactions is provided. The recent example of α-boryl radical formation from gem–diborylalkanes is also briefly discussed.
An enantioselective organo-catalyzed reaction of furanones with α, β-unsaturated ketones has been established herein, which provides an efficient access to chiral bicyclic γ-butyrolactones in good yields, enantioselectivities and diastereoselectivities. Further transformations of product are demonstrated. A diamine mediated catalytic cycle is proposed.
A highly efficient coupling of glycosyl stannanes and sulfonium salts enabled by synergistic Pd/Cu catalysis is disclosed, facilitating the construction of C-aryl/alkenyl glycals under mild conditions in high yields. The protocol tolerates a wide scope of functional groups including ketone, cyano, ester, amide, nitro, halide. The one-pot formal CH glycosylation starting from arene is demonstrated with a reaction sequence of dibenzothiophenylation/Stille coupling. Besides, a gram-scale reaction is performed successfully, showing the high applicability of this protocol.
After discovering a new class of two-dimensional (2D) material, i.e., MXene, a further new scope, came into existence for researchers. Due to their remarkable physical, chemical, and biological properties, MXenes find their role in almost every research discipline. They have been used in biosensors, bioimaging, tissue engineering, drug delivery systems, and other areas. The MXenes can be functionalized with a wide range of atoms/molecules, making them diverse materials. Therefore, the potential of using MXenes in nanofibers can be much more than expected. In this review, we will understand the structure, synthesis, and general properties of MXenes. We will explain using MXenes while encasing them into nanofibers, providing their specific properties. For instance, MXenes-incorporated nanofibers are used in biomedical applications, including soft and hard-tissue engineering and delivery of antimicrobials. Furthermore, MXenes, when incorporated into nanofibers, are used in promoting cellular differentiation, wound healing, and neural tissue restoration, which are briefly discussed in this communication.