Publications by authors named "Chaojun Li"

Glioblastoma is a highly aggressive primary brain tumor with glioblastoma stem cells (GSCs) enforcing the intra-tumoral hierarchy. Plasma cells (PCs) are critical effectors of the B-lineage immune system, but their roles in glioblastoma remain largely unexplored. Here, we leverage single-cell RNA and B cell receptor sequencing of tumor-infiltrating B-lineage cells and reveal that PCs are aberrantly enriched in the glioblastoma-infiltrating B-lineage population, experience low level of somatic hypermutation, and are associated with poor prognosis.

View Article and Find Full Text PDF

In the present investigation, fourteen unprecedented podocarpane diterpenoids strophiolosas A-J, L-N and P (1-10, 12-14, 16), two new cleistanthane derivatives strophiolosas Q-R (17-18), two new dibenzopyroan-ones and one new tetralone strophiolosas S-U (19-21), were isolated from the whole plant of Strophioblachia glandulosa. The structures were elucidated via various spectroscopic analysis, quantum chemistry calculations, and X-ray diffraction. Bioactivity test indicated that compounds 5 and 17 possessed promising anti-cardiac hypertrophy effect in vitro (IC values of 16.

View Article and Find Full Text PDF

Methyl groups rank among the most abundant carbon fragments found in natural products and small-molecule pharmaceuticals. The late-stage and environmentally friendly installation of these groups onto biologically active molecules has attracted widespread attention in both industry and academia. In 2008, we published the first use of a methyl radical derived from a peroxide toward a directed transition-metal catalysed C-H methylation.

View Article and Find Full Text PDF

Selective functionalisation of synthetically useful vinyl epoxides carbon-carbon (C-C) bond formation has been a major challenge for many years due to its unique inherent chemical reactivity. Non-stabilised carbanions in the form of organometallic reagents have been shown to be robust and versatile reagents in C-C bond formation; however, they are employed in superstoichiometric quantities, require the protection of active functional groups, and generate copious amounts of metallic waste. Therefore, the development of mild carbanion sources as simple alternatives is highly desired.

View Article and Find Full Text PDF

Transition-metal-catalyzed double/triple bond metathesis reactions have been well-established due to the ability of transition-metal catalysts to readily interact with π bonds, facilitating the progression of the entire reaction. However, activating σ-bonds to induce σ-bond metathesis is more challenging due to the absence of π bonds and the high bond energy of σ bonds. In this study, we present a novel photo-induced approach that does not rely on transition metals or photosensitizers to drive C-C and C-N σ-bond metathesis reactions.

View Article and Find Full Text PDF

The direct co-conversion of methane and carbon dioxide into valuable chemicals has been a longstanding scientific pursuit for carbon neutrality and combating climate change. Herein, we present a photo-driven chemical process that reforms these two major greenhouse gases together to generate green methanol and CO, two high-valued industrial chemicals. Isotopic labeling and control experiments indicate an oxygen-atom-graft occurs, wherein CO transfers one O into the C-H bond of CH via photo-activated interfacial catalysis with AuPd nanoparticles supported on GaN.

View Article and Find Full Text PDF

Deoxygenation of epoxides into alkenes is one of the most important strategies in organic synthesis, biomass conversions, and medicinal chemistry. Although metal-catalyzed direct deoxygenation provides one of the most commonly encountered protocols for the conversion of epoxides to alkenes, the requirement of expensive catalysts and extra reductants has largely limited their universal applicability. Herein, we report an efficient PPh-promoted metal-free strategy for deoxygenation of epoxides to generate alkene derivatives.

View Article and Find Full Text PDF

The homolysis of chemical bonds represents one of the most fundamental reactivities of excited molecules. Historically, it has been exploited to generate radicals under ultraviolet (UV) light irradiation. However, unlike most contemporary radical-generating mechanisms, the direct excitation to homolyze chemical bonds and produce aliphatic carbon-centered radicals under visible light remains rare, especially in metallaphotoredox cross couplings.

View Article and Find Full Text PDF

China is experiencing large-scale rural-urban migration and rapid urbanization, which have had significant impact on terrestrial carbon sink. However, the impact of rural-urban migration and its accompanying urban expansion on the carbon sink is unclear. Based on multisource remote sensing product data for 2000-2020, the soil microbial respiration equation, relative contribution rate, and threshold analysis, we explored the impact of rural depopulation on the carbon sink and its threshold.

View Article and Find Full Text PDF

The condensation of amino acids into peptides plays a crucial role in protein synthesis and is thus essential for understanding the origins of life. However, the spontaneous formation of peptides from amino acids in bulk aqueous media is energetically unfavorable, posing a challenge for elucidating plausible abiotic mechanisms. In this study, we investigate the formation of amide bonds between amino acids within highly supersaturated aerosol droplets containing dicyandiamide (DCD), a cyanide derivative potentially present on primordial Earth.

View Article and Find Full Text PDF
Article Synopsis
  • Meiosis is a complex process that is significantly influenced by how genes are regulated, but there's limited research on how transcriptional changes occur during the early stages of meiosis.
  • The study used single-cell ATAC-seq on human testis tissue and found key changes in gene activity as spermatocytes progressed from zygotene to pachytene, a pattern also observed in mice.
  • They identified 282 transcriptional regulators that change activity during this process and proposed that signals from Sertoli cells are crucial for regulating these changes, with implications for conditions like non-obstructive azoospermia (NOA).
View Article and Find Full Text PDF

Glioblastoma (GBM) is the most aggressive malignant primary brain tumor characterized by a highly heterogeneous and immunosuppressive tumor microenvironment (TME). The symbiotic interactions between glioblastoma stem cells (GSCs) and tumor-associated macrophages (TAM) in the TME are critical for tumor progression. Here, we identified that IFI35, a transcriptional regulatory factor, plays both cell-intrinsic and cell-extrinsic roles in maintaining GSCs and the immunosuppressive TME.

View Article and Find Full Text PDF

A well-defined Ru(II)-PNP complex demonstrated high activity in the anti-Markovnikov hydroalkylation of nonpolarized terminal alkenes via hydrazones. Hydrazone served as a carbanion equivalent to combine with the electrophilic alkene substrate upon activation by the ruthenium catalyst, forming a new C-C bond in a concerted pathway with N as the only theoretical byproduct. Experimental and computational studies suggested the existence of a push-pull interaction that activated the alkene for hydrazone addition and then deduced the mechanism.

View Article and Find Full Text PDF

In the vast majority of top-selling pharmaceutical and industrial products, phenolic structural motifs are highly prevalent. Non-functionalized simple phenols serve as building blocks in the synthesis of value-added chemicals. It is worth mentioning that lignin, being the largest renewable biomass source of aromatic building blocks in nature, mainly consists of phenolic units, which enable the production of structurally diverse phenols.

View Article and Find Full Text PDF

In mammals, the neonatal heart can regenerate upon injury within a short time after birth, while adults lose this ability. Metabolic reprogramming has been demonstrated to be critical for cardiomyocyte proliferation in the neonatal heart. Here, we reveal that cardiac metabolic reprogramming could be regulated by altering global protein lactylation.

View Article and Find Full Text PDF
Article Synopsis
  • The transition-metal-catalyzed cross-coupling methods like Ullmann condensation and Buchwald-Hartwig amination for forming C(sp)-N bonds produce toxic waste and require complex preparations of aryl halides or boronic acids.
  • The novel method presented uses nitroarenes directly as starting materials, allowing for the creation of both symmetrical and unsymmetrical di- and triarylamines in fewer steps and with less waste.
  • Successful scale-up experiments, late-stage functionalization of drug intermediates, and efficient production of hole-transporting materials demonstrate the practicality and effectiveness of this new synthetic protocol.
View Article and Find Full Text PDF

This article introduces a reductive coupling driven by visible-light, facilitating the synthesis of pyridine-substituted alcohols and amines through the reaction of aldehydes, ketones and imines with cyanopyridines. Hantzsch esters serve as reductants in this process, eliminating the need for transition-metals or photosensitizers. The method demonstrates extensive compatibility and finds utility in the late-stage functionalization of both natural and pharmaceutical products, offering a sustainable pathway for the diversification of chemical compounds.

View Article and Find Full Text PDF

Acute coronary syndrome (ACS) is one of the most common and severe forms of cardiovascular disease and has attracted worldwide attention with increased morbidity and mortality in recent years. There are few review studies in the field of its care in the form of bibliometric studies. We searched the Web of Science Core Collection database for articles and reviews in the area of ACS nursing for visual mapping analysis.

View Article and Find Full Text PDF

Catalytic electron donor-acceptor (EDA) complexes have recently emerged as a powerful and sustainable alternative to iridium- and ruthenium-based photoredox synthetic methods. Yet, these complexes remain underexplored and reliant on the use of meticulously designed acceptors that require previous installation. Herein, we report a novel EDA complex employing tris(4-methoxyphenyl) amine as a catalytic donor for the sulfonylation of alkenes using inexpensive and readily available sulfonyl chlorides.

View Article and Find Full Text PDF

Photocatalysis is an energy-saving and high-efficiency green environmental technology. Because of its wide band gap and low light utilization, few studies have been conducted on ZrO used as a photocatalytic material. In this paper, a corrosion-resistant superhydrophobic ZrO coating was prepared on the surface of Zr-based bulk metallic glass by electrochemical etching.

View Article and Find Full Text PDF
Article Synopsis
  • The liver can tell when the body has enough nutrients and sends messages to other parts to help balance everything!
  • When someone eats a ketogenic diet, the liver releases a signal called β-hydroxybutyrate (BHB) to help manage fat storage in a specific type of fat tissue!
  • If the liver can't produce BHB, the fat tissue starts storing more fat, but the liver isn't helped in reducing its own fat accumulation!
View Article and Find Full Text PDF
Article Synopsis
  • Dryness stress, like not enough water, can stop plants from growing well and hurt their ability to cool the Earth.
  • Research shows that while plants help reduce global warming a little, almost half of the areas where they grow aren't very sustainable because of dryness stress.
  • As the soil gets drier, it can lead to a big drop in plant growth, which means plants won't be able to cool the area as effectively, risking a huge part of the Earth's surface.
View Article and Find Full Text PDF

The direct functionalization of inert C-H bonds has long been a "holy grail" for the chemistry world. In this report, the direct C(sp)-N bond formation of unactivated alkanes is reported with a GaN based Mott-Schottky catalyst under photocatalytic reaction conditions. Long term stability and reaction efficiency (up to 92%) were achieved with this photocatalyst.

View Article and Find Full Text PDF

The decarboxylative Minisci reaction is a versatile tool for the direct C-H alkylation of heteroarenes, where stoichiometric amounts of oxidants or expensive, precious metal reagents are commonly used. Herein, we reported a photodriven decarboxylative Minisci reaction enabled by a gallium nitride-based heterogeneous photocatalyst under mild conditions. This method can be effectively applied to a broad substrate scope of acids, including primary, secondary, and tertiary carboxylic acids and -heteroarenes effectively.

View Article and Find Full Text PDF