Less Is More: Donor Engineering of a Stable Molecular Dye for Bioimaging in the NIR-IIb Window.

Fluorescence molecular imaging aims to enhance clarity in the region of interest, particularly in the near-infrared IIb window (NIR-IIb, 1500-1700 nm). To achieve this, we developed a novel small-molecule dye, named , based on classic cyanine dyes (heptamethine or pentamethine is essential for wavelengths beyond 1000 nm). By reducing excessive polymethine to a single methine and disrupting symmetry to form an asymmetric donor-π-acceptor (D-π-A) architecture, we enhanced the donor's electron-donating capability, yielding emission at 1088 nm.

Molecular Mechanism for the Unprecedented Metal-Independent Hydroxyl Radical Production from Thioureas and HO.

The most well-known hydroxyl radical (OH)-generating system is the classic iron-mediated Fenton reaction. Thiourea has been considered as an efficient OH scavenger and is frequently used to study the role of OH in various biochemical and medical research studies. Here we found that the highly reactive OH can be produced from thiourea and HO through a metal-independent pathway, as measured by electron spin resonance (ESR) secondary radical spin-trapping and fluorescent methods.

Design, Synthesis, and Imaging of a Stable Xanthene-Based Dye with NIR-II Emission up to 1450 nm.

The development of long-wavelength near-infrared II (NIR-II, 900-1700 nm) dyes is highly desirable but challenging. To achieve both red-shifted absorption/emission and superior imaging capabilities, a donor-acceptor-donor (D-A-D) xanthene core was strategically modified by extending π-conjugated double bonds and enhancing electron-donating properties. Two dyes named and were synthesized and exhibited notably red-shifted absorption/emission peaks at 942/1250 and 1098/1450 nm, respectively.

Effects of phosphorylation on CsTT12 transport function: A comparative phosphoproteomic analysis of flavonoid biosynthesis in tea plants (Camellia sinensis).

Monomeric flavan-3-ols and their oligomeric forms, proanthocyanidins (PAs), are closely related to the bitterness of tea beverages. Monomeric flavan-3-ols are characteristic flavor compounds in tea. Increasing the content of PAs and anthocyanins enhances the resistance of tea plants to pathogen invasion but decreases the quality of tea beverages.

Unique Fn3-like biosensor in σ/anti-σ factors for regulatory expression of major cellulosomal scaffoldins in Pseudobacteroides cellulosolvens.

Lignocellulolytic clostridia employ multiple pairs of alternative σ/anti-σ (SigI/RsgI) factors to regulate cellulosomal components for substrate-specific degradation of cellulosic biomass. The current model has proposed that RsgIs use a sensor domain to bind specific extracellular lignocellulosic components and activate cognate SigIs to initiate expression of corresponding cellulosomal enzyme genes, while expression of scaffoldins can be initiated by several different SigIs. Pseudobacteroides cellulosolvens contains the most complex known cellulosome system and the highest number of SigI-RsgI regulons yet discovered.

Extracytoplasmic polysaccharides control cellulosomal and non-cellulosomal systems in Herbivorax saccincola A7.

Herbivorax saccincola A7 is an anaerobic alkali-thermophilic lignocellulolytic bacterium that possesses a cellulosome and high xylan degradation ability. To understand the expression profile of extracellular enzymes by carbon sources, quantitative real-time PCR was performed on all cellulosomal and non-cellulosomal enzyme genes of H. saccincola A7 using cellulose and xylan as carbon sources.

Structural insight into the functional regulation of Elongation factor Tu by reactive oxygen species in Synechococcus elongatus PCC 7942.

In cyanobacteria, Elongation factor Tu (EF-Tu) plays a crucial role in the repair of photosystem II (PSII), which is highly susceptible to oxidative stress induced by light exposure and regulated by reactive oxygen species (ROS). However, the specific molecular mechanism governing the functional regulation of EF-Tu by ROS remains unclear. Previous research has shown that a mutated EF-Tu, where C82 is substituted with a Ser residue, can alleviate photoinhibition, highlighting the important role of C82 in EF-Tu photosensitivity.

Mechanistic Investigation into Chemiluminescence from 1,4-Benzoquinone.

Tetrahalogen-1,4-benzoquinone (THBQ) represents a category of HO-dependent substrates for chemiluminescence (CL), including tetrafluoro-, tetrachloro-, tetrabromo-, and tetraiodo-1,4-benzoquinone (TFBQ, TCBQ, TBBQ, and TIBQ). A deep understanding of the CL mechanism of THBQ is essential for all HO-dependent CL and even some bioluminescence. This article systematically investigates the CL process of THBQ by density functional theory and multireference state theory.

ι-Carrageenan catabolism is initiated by key sulfatases in the marine bacterium LL1.

Marine bacteria contribute substantially to cycle macroalgae polysaccharides in marine environments. Carrageenans are the primary cell wall polysaccharides of red macroalgae. The carrageenan catabolism mechanism and pathways are still largely unclear.

PolyQ-expanded ataxin-2 aggregation impairs cellular processing-body homeostasis via sequestering the RNA helicase DDX6.

Ataxin-2 (Atx2) is a polyglutamine (polyQ) tract-containing RNA-binding protein, while its polyQ expansion may cause protein aggregation that is implicated in the pathogenesis of neurodegenerative diseases such as spinocerebellar ataxia type 2 (SCA2). However, the molecular mechanism underlying how Atx2 aggregation contributes to the proteinopathies remains elusive. Here, we investigated the influence of Atx2 aggregation on the assembly and functionality of cellular processing bodies (P-bodies) by using biochemical and fluorescence imaging approaches.

Molecular mechanism of the metal-independent production of hydroxyl radicals by thiourea dioxide and HO.

It is well-known that highly reactive hydroxyl radicals (HO) can be produced by the classic Fenton system and our recently discovered haloquinone/HO system, but rarely from thiol-derivatives. Here, we found, unexpectedly, that HO can be generated from HO and thiourea dioxide (TUO), a widely used and environmentally friendly bleaching agent. A carbon-centered radical and sulfite were detected and identified as the transient intermediates, and urea and sulfate as the final products, with the complementary application of electron spin-trapping, oxygen-18 isotope labeling coupled with HPLC/MS analysis.

A cellulosomal double-dockerin module from Clostridium thermocellum shows distinct structural and cohesin-binding features.

Cellulosomes are intricate cellulose-degrading multi-enzymatic complexes produced by anaerobic bacteria, which are valuable for bioenergy development and biotechnology. Cellulosome assembly relies on the selective interaction between cohesin modules in structural scaffolding proteins (scaffoldins) and dockerin modules in enzymes. Although the number of tandem cohesins in the scaffoldins is believed to determine the complexity of the cellulosomes, tandem dockerins also exist, albeit very rare, in some cellulosomal components whose assembly and functional roles are currently unclear.

[Spatial and Temporal Distribution and Risk Assessment of Heavy Metals in Surface Water of Changshou Lake Reservoir, Chongqing].

To understand the water pollution status and environmental risks of Changshou Lake, the concentrations of heavy metals (Cr, Cu, Zn, As, Cd, and Pb) in the water were collected and analyzed during different seasons. The study investigated temporal and spatial variations, distribution characteristics, pollution levels, and health risks associated with heavy metals in Changshou Lake. The results showed that all six heavy metals were below than the Class Ⅰ standard of the Surface Water Environmental Quality Standard (GB 3838-2002), but recent years have witnessed an increasing trend, with Cu, As, and Pb showing a significant increase (<0.

The causal effect of hypertension, intraocular pressure, and diabetic retinopathy: a Mendelian randomization study.

Background: Previous research has indicated a vital association between hypertension, intraocular pressure (IOP), and diabetic retinopathy (DR); however, the relationship has not been elucidated. In this study, we aim to investigate the causal association of hypertension, IOP, and DR.

Methods: The genome-wide association study (GWAS) IDs for DR, hypertension, and IOP were identified from the Integrative Epidemiology Unit (IEU) Open GWAS database.

Boosting the Interfacial Stability of the LiPSCl Electrolyte with a Li Anode via In Situ Formation of a LiF-Rich SEI Layer and a Ductile Sulfide Composite Solid Electrolyte.

Due to its good mechanical properties and high ionic conductivity, the sulfide-type solid electrolyte (SE) can potentially realize all-solid-state batteries (ASSBs). Nevertheless, challenges, including limited electrochemical stability, insufficient solid-solid contact with the electrode, and reactivity with lithium, must be addressed. These challenges contribute to dendrite growth and electrolyte reduction.

Mechanistic Insights into the Bacterial Luciferase-based Bioluminescence Resonance Energy Transfer Luminescence: The Role of Protein Complex Dimer.

Bacterial bioluminescence holds significant potential in the realm of optical imaging due to the inherent advantages of bioluminescence and ease of operation. However, its practical utility is hindered by its low light intensity. The fusion of bacterial luciferase with a highly fluorescent protein has been demonstrated to significantly enhance autonomous luminescence.

Ataxin-2 sequesters Raptor into aggregates and impairs cellular mTORC1 signaling.

Ataxin-2 (Atx2) is a polyglutamine (polyQ) protein, in which abnormal expansion of the polyQ tract can trigger protein aggregation and consequently cause spinocerebellar ataxia type 2 (SCA2), but the mechanism underlying how Atx2 aggregation leads to proteinopathy remains elusive. Here, we investigate the molecular mechanism and cellular consequences of Atx2 aggregation by molecular cell biology approaches. We have revealed that either normal or polyQ-expanded Atx2 can sequester Raptor, a component of mammalian target of rapamycin complex 1 (mTORC1), into aggregates based on their specific interaction.

Six-point scleral fixation of a three-looped haptics one-piece posterior chamber intraocular lens by a single suture.

To evaluate a novel technique for six-point scleral fixation of a three-looped haptics posterior chamber intraocular lens (PCIOL) by a single suture. Nine eyes of nine patients were studied from September 2021 to March 2023. All patients had undergone vitrectomy.

Harnessing GMNP-loaded BMSC-derived EVs to target miR-3064-5p via MEG3 overexpression: Implications for diabetic osteoporosis therapy in rats.

Diabetic osteoporosis (DO) is a significant complication of diabetes, characterized by a decrease in bone mineral density and an increase in fracture risk. Magnetic nanoparticles (GMNPs) have emerged as potential drug carriers for various therapeutic applications. This study investigated the molecular mechanism of GMNPs loaded with bone marrow mesenchymal stem cell (BMSC) derived extracellular vesicles (EVs) overexpressing MEG3 target miR-3064-5p to induce NR4A3 for treating DO in rats.

A modified 23-G trocar and cannula system with lateral micropores for drainage of vitreous humor.

When primary angle-closure glaucoma occurs during an acute attack, routine phacoemulsification is challenging because of the high intra-ocular pressure (IOP) and shallow anterior chamber (AC). To reduce IOP and deepen the AC before phacoemulsification, a portion of the vitreous body is often removed. In this report, we introduce an extended trocar/cannula system with lateral micropores to drain the liquid vitreous before routine phacoemulsification to solve this problem.

Structure of the transcription open complex of distinct σ factors.

Bacterial σ factors of the σ-family are widespread in Bacilli and Clostridia and are involved in the heat shock response, iron metabolism, virulence, and carbohydrate sensing. A multiplicity of σ paralogues in some cellulolytic bacteria have been shown to be responsible for the regulation of the cellulosome, a multienzyme complex that mediates efficient cellulose degradation. Here, we report two structures at 3.

Key roles of β-glucosidase BglA for the catabolism of both laminaribiose and cellobiose in the lignocellulolytic bacterium Clostridium thermocellum.

The thermophilic bacterium Clostridium thermocellum efficiently degrades polysaccharides into oligosaccharides. The metabolism of β-1,4-linked cello-oligosaccharides is initiated by three enzymes, i.e.