peri-Fused polyaromatic molecular contacts for perovskite solar cells.

Molecule-based selective contacts have become a crucial component to ensure high-efficiency inverted perovskite solar cells1-5. These molecules always consist of a conjugated core with heteroatom substitution to render the desirable carrier-transport capability6-9. So far, the design of successful conjugation cores has been limited to two N-substituted π-conjugated structures, carbazole and triphenylamine, with molecular optimization evolving around their derivatives2,5,10-12. However, further improvement of the device longevity has been hampered by the concomitant limitations of the molecular stability induced by such heteroatom-substituted structures13,14. A more robust molecular contact without sacrificing the electronic properties is in urgent demand, but remains a challenge. Here we report a peri-fused polyaromatic core structure without heteroatom substitution that yields superior carrier transport and selectivity over conventional heteroatom-substituted core structures. This core structure produced a relatively chemically inert and structurally rigid molecular contact, which considerably improved the performance of perovskite solar cells in terms of both efficiency and durability. The champion device showed an efficiency up to 26.1% with greatly improved longevity under different accelerated-ageing tests.

Oriented nucleation in formamidinium perovskite for photovoltaics.

The black phase of formamidinium lead iodide (FAPbI3) perovskite shows huge promise as an efficient photovoltaic, but it is not favoured energetically at room temperature, meaning that the undesirable yellow phases are always present alongside it during crystallization1-4. This problem has made it difficult to formulate the fast crystallization process of perovskite and develop guidelines governing the formation of black-phase FAPbI3 (refs. 5,6). Here we use in situ monitoring of the perovskite crystallization process to report an oriented nucleation mechanism that can help to avoid the presence of undesirable phases and improve the performance of photovoltaic devices in different film-processing scenarios. The resulting device has a demonstrated power-conversion efficiency of 25.4% (certified 25.0%) and the module, which has an area of 27.83 cm2, has achieved an impressive certified aperture efficiency of 21.4%.

Innovative ochre processing and tool use in China 40,000 years ago.

Homo sapiens was present in northern Asia by around 40,000 years ago, having replaced archaic populations across Eurasia after episodes of earlier population expansions and interbreeding1-4. Cultural adaptations of the last Neanderthals, the Denisovans and the incoming populations of H. sapiens into Asia remain unknown1,5-7. Here we describe Xiamabei, a well-preserved, approximately 40,000-year-old archaeological site in northern China, which includes the earliest known ochre-processing feature in east Asia, a distinctive miniaturized lithic assemblage with bladelet-like tools bearing traces of hafting, and a bone tool. The cultural assembly of traits at Xiamabei is unique for Eastern Asia and does not correspond with those found at other archaeological site assemblages inhabited by archaic populations or those generally associated with the expansion of H. sapiens, such as the Initial Upper Palaeolithic8-10. The record of northern Asia supports a process of technological innovations and cultural diversification emerging in a period of hominin hybridization and admixture2,3,6,11.

LONP1-mediated mitochondrial quality control safeguards metabolic shifts in heart development.

The mitochondrial matrix AAA+ Lon protease (LONP1) degrades misfolded or unassembled proteins, which play a pivotal role in mitochondrial quality control. During heart development, a metabolic shift from anaerobic glycolysis to mitochondrial oxidative phosphorylation takes place, which relies strongly on functional mitochondria. However, the relationship between the mitochondrial quality control machinery and metabolic shifts is elusive. Here, we interfered with mitochondrial quality control by inactivating Lonp1 in murine embryonic cardiac tissue, resulting in severely impaired heart development, leading to embryonic lethality. Mitochondrial swelling, cristae loss and abnormal protein aggregates were evident in the mitochondria of Lonp1-deficient cardiomyocytes. Accordingly, the p-eIF2α-ATF4 pathway was triggered, and nuclear translocation of ATF4 was observed. We further demonstrated that ATF4 regulates the expression of Tfam negatively while promoting that of Glut1, which was responsible for the disruption of the metabolic shift to oxidative phosphorylation. In addition, elevated levels of reactive oxygen species were observed in Lonp1-deficient cardiomyocytes. This study revealed that LONP1 safeguards metabolic shifts in the developing heart by controlling mitochondrial protein quality, suggesting that disrupted mitochondrial quality control may cause prenatal cardiomyopathy.

Subcellular Translocation of Yorkie through the PRP4K-CRM1 Axis Regulates Antimicrobial Peptides Transcription and Defense against Bacterial Infection in Crab.

The Hippo signaling pathway plays important roles in innate immunity. In the current study, we found that bacterial infection did not influence mRNA and protein levels of yorkie (Yki), which is an important terminal molecule of the Hippo signaling pathway. However, bacterial infection promoted the translocation of Yki from the nucleus to the cytoplasm in Chinese mitten crab (Eriocheir sinensis), thus attenuating Yki-suppressed transcription of antimicrobial peptides through Cactus. Chromosome region maintenance 1 (CRM1)-silenced crab hemocytes significantly suppressed Yki translocation from the nucleus to the cytoplasm upon bacterial infection, resulting in significantly increased expression of Cactus, decreased expression of antimicrobial peptides, and higher bacterial susceptibility, which demonstrated the regulatory role of CRM1 in subcellular localization of Yki. However, RNA interference of Scalloped (Sd) exhibited no effect on the subcellular localization of Yki and its regulation of Cactus/antimicrobial peptides. Moreover, we elucidated that both CRM1 and Sd could interact with Yki and that the PRP4K-mediated phosphorylation of a conserved serine amino acid residue in the nuclear export signal of Yki is essential for interaction between Yki and CRM1; however, the phosphorylation did not affect the binding of Yki with Sd. We also found that bacterial infection significantly promoted the expression of PRP4K in hemocytes; RNA interference of PRP4K and phosphatase inhibitor suppressed Yki translocation from the nucleus to the cytoplasm, promoting Cactus expression and inhibiting antimicrobial peptide expression. Thus, subcellular localization of Yki regulates antibacterial infection through both PRP4K and CRM1 in crabs.

Lipoxin A4 modulates the PKA/CREB and NF-κB signaling pathway to mitigate chondrocyte catabolism and apoptosis in temporomandibular joint osteoarthritis.

Temporomandibular joint osteoarthritis (TMJ-OA) is characterized by the degradation of the extracellular matrix (ECM) in cartilage and the apoptosis of chondrocytes, which is caused by inflammation and disruptions of chondrocyte metabolism and inflammation. Lipoxin A4 (LXA4), a specialized pro-resolving mediator, has been shown to inhibit inflammation and regulate the balance between ECM synthesis and degradation. However, the therapeutic effects of LXA4 on TMJ-OA and its underlying mechanisms remain unclear. Interleukin-1 beta (IL-1ß)-induced chondrocyte and surgically induced TMJ-OA rat models were established in this study. The viability of chondrocytes treated with LXA4 was evaluated with the cell counting kit-8 (CCK-8) assay, while protein levels were assessed by western blot analysis, and the apoptosis rate was evaluated with terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labelling (TUNEL) staining. Histological analysis was conducted to evaluate the impact of LXA4 on cartilage degradation in TMJ-OA rat models. In vitro, the qRT-PCR and western blot analysis demonstrated that LXA4 facilitated the upregulation of collagen proteins (Collagen II) and decreased expression of matrix metalloproteinases (MMP-3, and MMP-13) associated with ECM modulation. LXA4 enhanced the TMJ-OA chondrocyte viability and decreased apoptotic rate. In vivo, histology and immunohistochemistry (IHC) analysis revealed that intraperitoneal injection of LXA4 contributed to the amelioration of chondrocyte injuries and deceleration of TMJ-OA. Transcriptomic sequencing revealed that cAMP signaling pathway was up-regulated and NF-κB signaling pathway was down-regulated in LXA4 treated group. LXA4 inhibited the phosphorylation of P65 and inhibitor of nuclear factor kappa B (IκBα) proteins while enhancing the phosphorylation PKA and CREB. This study demonstrates the potential of LXA4 as a therapeutic agent for suppressing chondrocyte catabolism and apoptosis by increasing PKA/CREB activity and decreasing NF-κB signaling.

Escherichia coli O157:H7 senses microbiota-produced riboflavin to increase its virulence in the gut.

Riboflavin is produced by most commensal bacteria in the human colon, where enterohemorrhagic Escherichia coli (EHEC) colonizes and causes diseases. Sensing environmental signals to site-specifically express the type-III secretion system (T3SS), which injects effectors into host cells leading to intestinal colonization and disease, is key to the pathogenesis of EHEC. Here, we reveal that EHEC O157:H7, a dominant EHEC serotype frequently associated with severe diseases, acquired a previously uncharacterized two-component regulatory system rbfSR, which senses microbiota-produced riboflavin to directly activate the expression of LEE genes encoding the T3SS in the colon. rbfSR is present in O157:H7 and O145:H28 but absent from other EHEC serotypes. The binding site of RbfR through which it regulates LEE gene expression was identified and is conserved in all EHEC serotypes and Citrobacter rodentium, a surrogate for EHEC in mice. Introducing rbfSR into C. rodentium enabled bacteria to sense microbiota-produced riboflavin in the mouse colon to increase the expression of LEE genes, causing increased disease severity in mice. Phylogenic analysis showed that the O55:H7 ancestor of O157:H7 obtained rbfSR which has been kept in O157:H7 since then. Thus, acquiring rbfSR represents an essential step in the evolution of the highly pathogenic O157:H7. The expression of LEE genes and cell attachment ability of other EHEC serotypes in the presence of riboflavin significantly increased when rbfSR was introduced into them, indicating that those serotypes are ready to use RbfSR to increase their pathogenicity. This may present a potential public health issue as horizontal gene transfer is frequent in enteric bacteria.

Genome-wide identification and expression analysis of the Eriobotrya japonica TIFY gene family reveals its functional diversity under abiotic stress conditions.

BACKGROUND: Plant-specific TIFY proteins are widely found in terrestrial plants and play important roles in plant adversity responses. Although the genome of loquat at the chromosome level has been published, studies on the TIFY family in loquat are lacking. Therefore, the EjTIFY gene family was bioinformatically analyzed by constructing a phylogenetic tree, chromosomal localization, gene structure, and adversity expression profiling in this study. RESULTS: Twenty-six EjTIFY genes were identified and categorized into four subfamilies (ZML, JAZ, PPD, and TIFY) based on their structural domains. Twenty-four EjTIFY genes were irregularly distributed on 11 of the 17 chromosomes, and the remaining two genes were distributed in fragments. We identified 15 covariate TIFY gene pairs in the loquat genome, 13 of which were involved in large-scale interchromosomal segmental duplication events, and two of which were involved in tandem duplication events. Many abiotic stress cis-elements were widely present in the promoter region. Analysis of the Ka/Ks ratio showed that the paralogous homologs of the EjTIFY family were mainly subjected to purifying selection. Analysis of the RNA-seq data revealed that a total of five differentially expressed genes (DEGs) were expressed in the shoots under gibberellin treatment, whereas only one gene was significantly differentially expressed in the leaves; under both low-temperature and high-temperature stresses, there were significantly differentially expressed genes, and the EjJAZ15 gene was significantly upregulated under both low- and high-temperature stress. RNA-seq and qRT-PCR expression analysis under salt stress conditions revealed that EjJAZ2, EjJAZ4, and EjJAZ9 responded to salt stress in loquat plants, which promoted resistance to salt stress through the JA pathway. The response model of the TIFY genes in the jasmonic acid pathway under salt stress in loquat was systematically summarized. CONCLUSIONS: These results provide a theoretical basis for exploring the characteristics and functions of additional EjTIFY genes in the future. This study also provides a theoretical basis for further research on breeding for salt stress resistance in loquat. RT-qPCR analysis revealed that the expression of one of the three EjTIFY genes increased and the expression of two decreased under salt stress conditions, suggesting that EjTIFY exhibited different expression patterns under salt stress conditions.

Chiral Bifunctional Phosphine Ligand Enables Asymmetric Trapping of Catalytic Vinyl Gold Carbene Species.

Bifunctional ligand-enabled cooperative gold catalysis accelerates nucleophilic attacks and offers a versatile strategy to achieve asymmetric gold catalysis. Distinct from the prior studies employing alkyne/allene as the electrophilic site, this work engages an in situ-generated alkenyl/acyl gold carbene in a ligand-facilitated attack by an alcoholic nucleophile. With an amide-functionalized chiral binaphthylphosphine ligand, γ-alkoxy-α,ß-unsaturated imides are formed with excellent enantiomeric excesses. The intermediacy of a carbene species is supported by its alternative access via dediazotization. The reaction tolerates a broad range of alcohols and can accommodate dienynamide substrates, in addition to arylenynamides. This work avails a versatile strategy to enrich gold chemistry and achieve challenging enantioselective gold catalysis via ligand-facilitated enantioselective trapping of reactive intermediates.

Enantioselective Cyanofunctionalization of Aromatic Alkenes via Radical Anions.

Alkene radical ions constitute an integral and unique class of reactive intermediates for the synthesis of valuable compounds because they have both unpaired spins and charge. However, relatively few synthetic applications of alkene radical anions have emerged due to a dearth of generally applicable and mild radical anion generation approaches. Precise control over the chemo- and stereoselectivity in alkene radical anion-mediated processes represents another long-standing challenge due to their high reactivity. To overcome these issues, here, we develop a new redox-neutral strategy that seamlessly merges photoredox and copper catalysis to enable the controlled generation of alkene radical anions and their orthogonal enantioselective cyanofunctionalization via distonic-like species. This new strategy enables highly regio-, chemo-, and enantioselective hydrocyanation, deuterocyanation, and cyanocarboxylation of alkenes without stoichiometric reductants or oxidants under visible light irradiation. This protocol provides a new blueprint for the exploration of the transformation potential of alkene radical anions.

Adoptive therapy with cytomegalovirus-specific cytotoxic T lymphocytes for refractory cytomegalovirus DNAemia and disease after allogeneic haematopoietic stem cell transplantation.

Cytomegalovirus (CMV) DNAemia and disease are common complications in patients undergoing allogeneic haematopoietic stem cell transplantation (allo-HSCT). Few studies have compared the efficacy and safety of the HSCT donor and third-party CMV-specific cytotoxic T lymphocytes (CMV-CTLs) in the treatment of CMV DNAemia and disease. In this study, we retrospectively compared the efficacy and safety of HSCT donor and third-party CMV-CTLs in patients with refractory CMV DNAemia or disease after allo-HSCT at our centre from January 2017 to September 2021. Fifty-three patients who received CMV-CTL therapy were enrolled, including 40 in the donor group and 13 in the third-party group, and they were adults aged 18 years or older. Within 6 weeks of treatment, 26 (65.0%) and 9 (69.2%) patients achieved complete response in the donor and third-party groups (p = 1.000). The 2-year overall survival was 59.6% (95% CI 46.1%-77.1%) and 53.8% (32.6%-89.1%) in the donor and third-party groups (p = 0.860). Four (10.0%) patients in the donor group and two (15.4%) patients in the third-party group developed acute graft-versus-host disease within 3 months after CMV-CTL infusions. In conclusion, our data suggest that donor and third-party CMV-CTLs have comparable efficacy and safety for refractory CMV DNAemia and disease.

Genome-wide identification of kiwifruit K+ channel Shaker family members and their response to low-K+ stress.

BACKGROUND: 'Hongyang' kiwifruit (Actinidia chinensis cv 'Hongyang') is a high-quality variety of A. chinensis with the advantages of high yield, early ripening, and high stress tolerance. Studies have confirmed that the Shaker K+ genes family is involved in plant uptake and distribution of potassium (K+). RESULTS: Twenty-eight Shaker genes were identified and analyzed from the 'Hongyang' kiwifruit (A. chinensis cv 'Hongyang') genome. Subcellular localization results showed that more than one-third of the AcShaker genes were on the cell membrane. Phylogenetic analysis indicated that the AcShaker genes were divided into six subfamilies (I-VI). Conservative model, gene structure, and structural domain analyses showed that AcShaker genes of the same subfamily have similar sequence features and structure. The promoter cis-elements of the AcShaker genes were classified into hormone-associated cis-elements and environmentally stress-associated cis-elements. The results of chromosomal localization and duplicated gene analysis demonstrated that AcShaker genes were distributed on 18 chromosomes, and segmental duplication was the prime mode of gene duplication in the AcShaker family. GO enrichment analysis manifested that the ion-conducting pathway of the AcShaker family plays a crucial role in regulating plant growth and development and adversity stress. Compared with the transcriptome data of the control group, all AcShaker genes were expressed under low-K+stress, and the expression differences of three genes (AcShaker15, AcShaker17, and AcShaker22) were highly significant. The qRT-PCR results showed a high correlation with the transcriptome data, which indicated that these three differentially expressed genes could regulate low-K+ stress and reduce K+ damage in kiwifruit plants, thus improving the resistance to low-K+ stress. Comparison between the salt stress and control transcriptomic data revealed that the expression of AcShaker11 and AcShaker18 genes was significantly different and lower under salt stress, indicating that both genes could be involved in salt stress resistance in kiwifruit. CONCLUSION: The results showed that 28 AcShaker genes were identified and all expressed under low K+ stress, among which AcShaker22 was differentially and significantly upregulated. The AcShaker22 gene can be used as a candidate gene to cultivate new varieties of kiwifruit resistant to low K+ and provide a reference for exploring more properties and functions of the AcShaker genes.

Coxsackievirus A6 2C protein antagonizes IFN-ß production through MDA5 and RIG-I depletion.

IMPORTANCE: Coxsackievirus A6 (CV-A6) is a major emerging pathogen associated with atypical hand, foot, and mouth disease and can cause serious complications such as encephalitis, acute flaccid paralysis, and neurorespiratory syndrome. Therefore, revealing the associated pathogenic mechanisms could benefit the control of CV-A6 infections. In this study, we demonstrate that the nonstructural 2CCV-A6 suppresses IFN-ß production, which supports CV-A6 infection. This is achieved by depleting RNA sensors such as melanoma differentiation-associated gene 5 and retinoic acid-inducible gene I (RIG-I) through the lysosomal pathway. Such a function is shared by 2CEV-A71 and 2CCV-B3 but not 2CCV-A16, suggesting the latter might have an alternative way to promote viral replication. This study broadens our understanding of enterovirus 2C protein regulation of the RIG-I-like receptor signaling pathway and reveals a novel mechanism by which CV-A6 and other enteroviruses evade the host innate immune response. These findings on 2C may provide new therapeutic targets for the development of effective inhibitors against CV-A6 and other enterovirus infections.

EBD: an eye biomarker database.

MOTIVATION: Many ophthalmic disease biomarkers have been identified through comprehensive multiomics profiling, and hold significant potential in advancing the diagnosis, prognosis, and management of diseases. Meanwhile, the eye itself serves as a natural biomarker for several systemic diseases including neurological, renal, and cardiovascular systems. We aimed to collect and standardize this eye biomarkers information and construct the eye biomarker database (EBD) to provide ophthalmologists with a platform to search, analyze, and download these eye biomarker data. RESULTS: In this study, we present the EBD , a world-first online compilation comprising 889 biomarkers for 26 ocular diseases and 939 eye biomarkers for 181 systemic diseases. The EBD also includes the information of 78 "nonbiomarkers"-the objects that have been proven cannot be biomarkers. Biological function and network analysis were conducted for these ocular disease biomarkers, and several hub pathways and common network topology characteristics were newly identified, which may promote future ocular disease biomarker discovery and characterizes the landscape of biomarkers for eye diseases at the pathway and network level. The EBD is expected to yield broader utility among developmental biologists and clinical scientists in and outside of the eye field by assisting in the identification of biomarkers linked to eye disorders and related systemic diseases. AVAILABILITY AND IMPLEMENTATION: EBD is available at http://www.eyeseeworld.com/ebd/index.html.

Blockade of PI3K/AKT signaling pathway by Astragaloside IV attenuates ulcerative colitis via improving the intestinal epithelial barrier.

BACKGROUND: The specific pathogenesis of UC is still unclear, but it has been clear that defects in intestinal barrier function play an important role in it. There is a temporary lack of specific drugs for clinical treatment. Astragaloside IV (AS-IV) is one of the main active ingredients extracted from Astragalus root and is a common Chinese herbal medicine for the treatment of gastrointestinal diseases. This study aimed to determine whether AS-IV has therapeutic value for DSS or LPS-induced intestinal epithelial barrier dysfunction in vivo and in vitro and its potential molecular mechanisms. METHODS: The intestinal tissues from UC patients and colitis mice were collected, intestinal inflammation was observed by colonoscopy, and mucosal barrier function was measured by immunofluorescence staining. PI3K/AKT signaling pathway activator YS-49 and inhibitor LY-29 were administered to colitic mice to uncover the effect of this pathway on gut mucosal barrier modulation. Then, network pharmacology was used to screen Astragaloside IV (AS-IV), a core active component of the traditional Chinese medicine Astragalus membranaceus. The potential of AS-IV for intestinal barrier function repairment and UC treatment through blockade of the PI3K/AKT pathway was further confirmed by histopathological staining, FITC-dextran, transmission electron microscopy, ELISA, immunofluorescence, qRT-PCR, and western blotting. Finally, 16 S rRNA sequencing was performed to uncover whether AS-IV can ameliorate UC by regulating gut microbiota homeostasis. RESULTS: Mucosal barrier function was significantly damaged in UC patients and murine colitis, and the activated PI3K/AKT signaling pathway was extensively involved. Both in vivo and vitro showed that the AS-IV-treated group significantly relieved inflammation and improved intestinal epithelial permeability by inhibiting the activation of the PI3K/AKT signaling pathway. In addition, microbiome data found that gut microbiota participates in AS-IV-mediated intestinal barrier recovery as well. CONCLUSIONS: Our study highlights that AS-IV exerts a protective effect on the integrality of the mucosal barrier in UC based on the PI3K/AKT pathway, and AS-IV may serve as a novel AKT inhibitor to provide a potential therapy for UC.

Photothermal metasurface with polarization and wavelength multiplexing.

Controlling temperature distribution at the micro/nano-scale brings new applications in many fields such as physics, chemistry and biology. This paper proposes a photothermal metasurface that employs polarization and wavelength multiplexing to regulate various temperature distributions at the micro/nano-scale. Such a photothermal metasurface is numerically validated by the finite element method. Firstly, the inversion algorithm is used to calculate the thermal power density distribution, which is decided by a given temperature distribution. Then, based on the bottom-up design method, (a) the library of absorption cross sections of gold nanoparticles is established by resizing nanoparticles; (b) the single pixel is constructed for wavelength and polarization multiplexing; (c) the overall structure of a photothermal metasurface is optimized and established. Finally, four given temperature distributions, combining the multiplexing of two orthogonal polarizations and two wavelengths, are achieved in the same area. The simulation results well confirm the feasibility of photothermal multiplexing. Such photothermal metasurface provides solutions for flexible control of temperature distribution at the micro/nano-scale.

Excessive iron deposition in root apoplast is involved in growth arrest of roots in response to low pH.

The rhizotoxicity of protons (H+) in acidic soils is a fundamental constraint that results in serious yield losses. However, the mechanisms underlying H+-mediated inhibition of root growth are poorly understood. In this study, we revealed that H+-induced root growth inhibition in Arabidopsis depends considerably on excessive iron deposition in the root apoplast. Reducing such aberrant iron deposition by decreasing the iron supply or disrupting the ferroxidases LOW PHOSPHATE ROOT 1 (LPR) and LPR2 attenuates the inhibitory effect of H+ on primary root growth efficiently. Further analysis showed that excessive iron deposition triggers a burst of highly reactive oxygen species, consequently impairing normal root development. Our study uncovered a valuable strategy for improving the ability of plants to tolerate H+ toxicity by manipulating iron availability.

Ultra-thin DLC diaphragm-based optical fiber sensor achieving a highly sensitive and broadband acoustic response.

In the design of an extrinsic Fabry-Perot interferometer (EFPI) acoustic sensor, broadband response and high-sensitivity sensing are usually conflicting and need to be carefully balanced. Here, we present a novel, to the best of our knowledge, optical fiber acoustic sensor based on an ultra-thin diamond-like carbon (DLC) film, fabricated using the plasma-enhanced chemical vapor deposition method, and transferred by a surface-energy-assisted method. The sensor exhibits a broadband response ranging from 200 Hz to 100 kHz, maintains an average sensitivity of 457.3 mV/Pa within the range of 6 to 30 kHz, and can detect weak acoustic signals down to 3.23 µPa/Hz1/2@16.19 kHz. The combination of an ultra-thin DLC film with a relatively high Young's modulus and internal stresses results in a trade-off between high sensitivity and a broadband response. This performance demonstrates that our sensor is among the most advanced in the EFPI acoustic sensor family, with significant potential for applications such as photoacoustic spectroscopy, defect diagnosis, and bio-imaging.

Phenanthrothiophene-Triazine Star-Shaped Discotic Liquid Crystals: Synthesis, Self-Assembly, and Stimuli-Responsive Fluorescence Properties.

Lipophilic biphenylthiophene- and phenanthrothiophene-triazine compounds, BPTTn and CPTTn, respectively, were prepared by a tandem procedure involving successive Suzuki-Miyaura coupling and Scholl cyclodehydrogenation reactions. These compounds display photoluminescence in solution and in thin film state, solvatochromism with increasing solvent's polarity, as well as acidochromism and metal ion recognition stimuli-responsive fluorescence. Protonation of BPTT10 and CPTT10 by trifluoroacetic acid results in fluorescence quenching, which is reversibly restored once treated with triethylamine (ON-OFF switch). DFT computational studies show that intramolecular charge transfer (ICT) phenomena occurs for both molecules, and reveal that protonation enhances the electron-withdrawing ability of the triazine core and reduces the band gap. This acidochromic behavior was applied to a prototype fluorescent anti-counterfeiting device. They also specifically recognize Fe3+ through coordination, and the recognition mechanism is closely related to the photoinduced electron transfer between Fe3+ and BPTT10/CPTT10. CPTTn self-assemble into columnar rectangular (Colrec) mesophase, which can be modulated by oleic acid via the formation of a hydrogen-bonded supramolecular liquid crystal hexagonal Colhex mesophase. Finally, CPTTn also form organic gels in alkanes at low critical gel concentration (3.0 mg/mL). Therefore, these star-shaped triazine molecules possess many interesting features and thus hold great promises for information processing, liquid crystal semiconductors and organogelators.

Neuroprotective Effects of CXCR2 Antagonist SB332235 on Traumatic Brain Injury Through Suppressing NLRP3 Inflammasome.

The inflammatory process mediated by nucleotide-binding oligomerization domain (NOD)-like receptor family pyrin domain comprising 3 (NLRP3) inflammasome plays a predominant role in the neurological dysfunction following traumatic brain injury (TBI). SB332235, a highly selective antagonist of chemokine receptor 2 (CXCR2), has been demonstrated to exhibit anti-inflammatory properties and improve neurological outcomes in the central nervous system. We aimed to determine the neuroprotective effects of SB332235 in the acute phase after TBI in mice and to elucidate its underlying mechanisms. Male C57BL/6J animals were exposed to a controlled cortical impact, then received 4 doses of SB332235, with the first dose administered at 30 min after TBI, followed by additional doses at 6, 24, and 30 h. Neurological defects were assessed by the modified neurological severity score, while the motor function was evaluated using the beam balance and open field tests. Cognitive performance was evaluated using the novel object recognition test. Brain tissues were collected for pathological, Western blot, and immunohistochemical analyses. The results showed that SB332235 significantly ameliorated TBI-induced deficits, including motor and cognitive impairments. SB332235 administration suppressed expression of both CXCL1 and CXCR2 in TBI. Moreover, SB332235 substantially mitigated the augmented expression levels and activation of the NLRP3 inflammasome within the peri-contusional cortex induced by TBI. This was accompanied by the blocking of subsequent production of pro-inflammatory cytokines. Additionally, SB332235 hindered microglial activity induced by TBI. These findings confirmed the neuroprotective effects of SB332235 against TBI, and the involved mechanisms were in part due to the suppression of NLRP3 inflammasome activity. This study suggests that SB332235 may act as an anti-inflammatory agent to improve functional outcomes in brain injury when applied clinically.