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1.
Int J Mol Sci ; 25(10)2024 May 16.
Article in English | MEDLINE | ID: mdl-38791460

ABSTRACT

The TIFY gene family (formerly known as the zinc finger proteins expressed in inflorescence meristem (ZIM) family) not only functions in plant defense responses but also are widely involved in regulating plant growth and development. However, the identification and functional analysis of TIFY proteins remain unexplored in Orchidaceae. Here, we identified 19 putative TIFY genes in the Phalaenopsis aphrodite genome. The phylogenetic tree classified them into four subfamilies: 14 members from JAZ, 3 members from ZML, and 1 each from PPD and TIFY. Sequence analysis revealed that all Phalaenopsis TIFY proteins contained a TIFY domain. Exon-intron analysis showed that the intron number and length of Phalaenopsis TIFY genes varied, whereas the same subfamily and subgroup genes had similar exon or intron numbers and distributions. The most abundant cis-elements in the promoter regions of the 19 TIFY genes were associated with light responsiveness, followed by MeJA and ABA, indicating their potential regulation by light and phytohormones. The 13 candidate TIFY genes screened from the transcriptome data exhibited two types of expression trends, suggesting their different roles in cell proliferation and cell expansion of floral organ growth during Phalaenopsis flower opening. Overall, this study serves as a background for investigating the underlying roles of TIFY genes in floral organ growth in Phalaenopsis.


Subject(s)
Flowers , Gene Expression Regulation, Plant , Multigene Family , Orchidaceae , Phylogeny , Plant Proteins , Orchidaceae/genetics , Orchidaceae/growth & development , Flowers/genetics , Flowers/growth & development , Plant Proteins/genetics , Plant Proteins/metabolism , Genome, Plant , Gene Expression Profiling , Transcription Factors/genetics , Transcription Factors/metabolism , Zinc Fingers/genetics
2.
Chem Commun (Camb) ; 60(33): 4475-4478, 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38563956

ABSTRACT

A hydrogen-bonded organic framework (HOF) consisting of a 9,10-diphenylanthracene carboxylic derivative, DPACOOH, was developed for solid state triplet-triplet annihilation upconversion (TTA-UC). The HOF sample shows a 70% increase in upconversion quantum yield and a lower threshold value of 126.0 mW cm-2 compared to those of the disordered powder sample, due to a 43% longer triplet diffusion length in HOF than that in the powder sample.

3.
Angew Chem Int Ed Engl ; : e202402673, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38656534

ABSTRACT

Repurposing enzymes to catalyze non-natural asymmetric transformations that are difficult to achieve using traditional chemical methods is of significant importance. Although radical C-O bond formation has emerged as a powerful approach for constructing oxygen-containing compounds, controlling the stereochemistry poses a great challenge. Here we present the development of a dual bio-/photo-catalytic system comprising an ene-reductase and an organic dye for achieving stereoselective lactonizations. By integrating directed evolution and photoinduced single electron oxidation, we repurposed engineered ene-reductases to steer non-natural radical C-O formations (one C-O bond for hydrolactonizations and lactonization-alkylations while two C-O bonds for lactonization-oxygenations). This dual catalysis gave a new approach to a diverse array of enantioenhanced 5- and 6-membered lactones with vicinal stereocenters, part of which bears a quaternary stereocenter (up to 99% enantiomeric excess, up to 12.9:1 diastereomeric ratio). Detailed mechanistic studies, including computational simulations, uncovered the synergistic effect of the enzyme and the externally added organophotoredox catalyst Rh6G.

4.
J Transl Med ; 22(1): 174, 2024 Feb 18.
Article in English | MEDLINE | ID: mdl-38369502

ABSTRACT

BACKGROUND: Overexpression of T-cell immunoglobulin and mucin domain-containing protein 3 (TIM3) is related to the exhaustion of CD8+ tumor-infiltrating lymphocytes (TILs) in diffuse large B-cell lymphoma (DLBCL). However, the mechanism of TIM3-mediated CD8+TILs exhaustion in DLBCL remains poorly understood. Therefore, we aimed to clarify the potential pathway involved in TIM3-mediated CD8+TILs exhaustion and its significance in DLBCL. METHODS: The expression of TIM3 and its correlation with CD8+TILs exhaustion, the key ligand of TIM3, and the potential pathway of TIM3-mediated CD8+TILs exhaustion in DLBCL were analyzed using single-cell RNA sequencing and validated by RNA sequencing. The biological significance of TIM3-related pathway in DLBCL was investigated based on RNA sequencing, immunohistochemistry, and reverse transcription-quantitative polymerase chain reaction data. Finally, the possible regulatory mechanism of TIM3-related pathway in DLBCL was explored using single-cell RNA sequencing and RNA sequencing. RESULTS: Our results demonstrated that CD8+TILs, especially the terminally exhausted state, were the major clusters that expressed TIM3 in DLBCL. Galectin-9, mainly expressed in M2 macrophages, is the key ligand of TIM3 and can induce the exhaustion of CD8+TILs through TIM3/Galectin-9 pathway. Meanwhile, high TIM3/Galectin-9 enrichment is related to immunosuppressive tumor microenvironment, severe clinical manifestations, inferior prognosis, and poor response to CHOP-based chemotherapy, and can predict the clinical efficacy of immune checkpoint blockade therapy in DLBCL. Furthermore, the TIM3/Galectin-9 enrichment in DLBCL may be regulated by the IFN-γ signaling pathway. CONCLUSIONS: Our study highlights that TIM3/Galectin-9 pathway plays a crucial role in CD8+TILs exhaustion and the immune escape of DLBCL, which facilitates further functional studies and could provide a theoretical basis for the development of novel immunotherapy in DLBCL.


Subject(s)
CD8-Positive T-Lymphocytes , Galectins , Hepatitis A Virus Cellular Receptor 2 , Lymphoma, Large B-Cell, Diffuse , Humans , Hepatitis A Virus Cellular Receptor 2/metabolism , Ligands , Lymphocytes, Tumor-Infiltrating , Lymphoma, Large B-Cell, Diffuse/pathology , Tumor Microenvironment , Galectins/metabolism
5.
Angew Chem Int Ed Engl ; 63(14): e202318629, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38299700

ABSTRACT

Flavoenzymes can mediate a large variety of oxidation reactions through the activation of oxygen. However, the O2 activation chemistry of flavin enzymes is not yet fully exploited. Normally, the O2 activation occurs at the C4a site of the flavin cofactor, yielding the flavin C4a-(hydro)hydroperoxyl species in monooxygenases or oxidases. Using extensive MD simulations, QM/MM calculations and QM calculations, our studies reveal the formation of the common nucleophilic species, Flavin-N5OOH, in two distinct flavoenzymes (RutA and EncM). Our studies show that Flavin-N5OOH acts as a powerful nucleophile that promotes C-N cleavage of uracil in RutA, and a powerful base in the deprotonation of substrates in EncM. We reason that Flavin-N5OOH can be a common reactive species in the superfamily of flavoenzymes, which accomplish generally selective general base catalysis and C-X (X=N, S, Cl, O) cleavage reactions that are otherwise challenging with solvated hydroxide ion base. These results expand our understanding of the chemistry and catalysis of flavoenzymes.


Subject(s)
Flavins , Mixed Function Oxygenases , Flavins/metabolism , Mixed Function Oxygenases/metabolism , Oxidation-Reduction , Oxidoreductases , Organic Chemicals
6.
Chem Asian J ; 19(7): e202301147, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38334040

ABSTRACT

Fluorescent mechanophores can indicate the deformation or damage in polymers. The development of mechanophores with multi-triggered response is of great interest. Herein, Diels-Alder (DA) adducts are incorporated into linear poly(methyl acrylate) PMA-BA and network poly(hexyl methacrylate) (PHMA) as mechanophores to detect the stress caused by ultrasound, freezing, and compression. The DA mechanophores undergo retro-DA reaction to release 9-styrylanthracene chromophore upon applying force, resulting in cyan fluorescence. The dissociation ratio of the DA mechanophore after pulsed ultrasonication of PMA-BA solution for 240 minutes is estimated to be 52 % by absorption spectra and 1H NMR. Additionally, the rate constant of mechanical cleavage is calculated to be 1.2×10-4 min-1⋅kDa-1 with the decrease in molecular weight from 69 to 22 kDa measured by gel permeation chromatography. Freezing of PHMA gels as well as compression of PHMA bulk samples turn-on the DA mechanophores, revealing the microscale fracture. Photon upconversion responses toward various force stimuli are also achieved in both polymer solutions and bulk samples by doping platinum octaethylporphyrin (PtOEP) or palladium meso-tetraphenyltetrabenzoporphyrin (PdTPTBP) sensitizers with multiple excitation wavelengths.

7.
Langmuir ; 40(10): 5326-5337, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38408337

ABSTRACT

Capacitors with zinc ions, with excellent stabilities, low cost, and high energy density, are expected to be promising energy storage devices. However, the development of zinc-ion capacitors is quietly restricted by low specific capacity and cycling stability. Herein, to overcome these limitations, honeycomb-structured S, N-codoped carbon (SNPC) is constructed by one-pot calcination of waste corn bracts and thiourea. The honeycomb structure of SNPC is demonstrated to provide abundant active sites that can enhance the extron/ion transport, conductivity for high power export, and ion adsorption capacity in energy storage applications, leading to a higher electrochemical performance achieved. The electrolytes of zinc salt have also been studied. It reveals that the SNPC electrode presents the best electrochemical performance in a 2 M ZnSO4 and 0.5 M ZnCl2 electrolyte mixture because in the electrolyte mixture, Cl- can replace the existing bound water in the solvation structure to form an anion-type water-free solvation structure ZnCl42-. The SNPC-800 electrode with a highly improved surface area (∼909.0 m2 g-1) is proved to be more suitable as the electrode than other materials. Aqueous zinc-ion capacitors (ZICs) have been assembled by the honeycomb-structured SNPC-800 as the cathode, which can achieve a relatively wide working voltage range of 0.1-1.8 V. The SNPC-800 ZICs exhibit a superior specific capacity of 179.1 mA h g-1 at 0.1 A g-1. The energy density of SNPC-800 ZICs reaches an impressive value of 89.6 Wh kg-1 at 53.8 W kg-1, and it sustains 28.3 Wh kg-1 at 1997.6 W kg-1. In addition, there is 99.8% capacity retention in the SNPC-800 ZICs over 5000 cycles. The absorption energy in SPNC is much higher than that in undoped CPC, as confirmed by density functional theory, which reveals that introducing of heteroatoms (S, N) has a comparatively active advantage at increasing the Zn-ion storage capacity. This work proposes a practical strategy for the effective recycling of waste biomass materials into honeycomb carbon electrode materials. Moreover, the honeycomb carbon-based ZICs with excellent electrochemical performance and long-term cycling stability possess great potential to be a superior cathode in practical applications.

8.
J Am Chem Soc ; 145(46): 25304-25317, 2023 11 22.
Article in English | MEDLINE | ID: mdl-37955571

ABSTRACT

Particulate methane monooxygenase (pMMO) plays a critical role in catalyzing the conversion of methane to methanol, constituting the initial step in the C1 metabolic pathway within methanotrophic bacteria. However, the membrane-bound pMMO's structure and catalytic mechanism, notably the copper's valence state and genuine active site for methane oxidation, have remained elusive. Based on the recently characterized structure of membrane-bound pMMO, extensive computational studies were conducted to address these long-standing issues. A comprehensive analysis comparing the quantum mechanics/molecular mechanics (QM/MM) molecular dynamics (MD) simulated structures with cryo-EM data indicates that both the CuC and CuD sites tend to stay in the Cu(I) valence state within the membrane environment. Additionally, the concurrent presence of Cu(I) at both CuC and CuD sites leads to the significant reduction of the ligand-binding cavity situated between them, making it less likely to accommodate a reductant molecule such as durohydroquinone (DQH2). Subsequent QM/MM calculations reveal that the CuD(I) site is more reactive than the CuC(I) site in oxygen activation, en route to H2O2 formation and the generation of Cu(II)-O•- species. Finally, our simulations demonstrate that the natural reductant ubiquinol (CoQH2) assumes a productive binding conformation at the CuD(I) site but not at the CuC(I) site. This provides evidence that the true active site of membrane-bound pMMOs may be CuD rather than CuC. These findings clarify pMMO's catalytic mechanism and emphasize the membrane environment's pivotal role in modulating the coordination structure and the activity of copper centers within pMMO.


Subject(s)
Copper , Reducing Agents , Copper/chemistry , Hydrogen Peroxide , Methane/chemistry , Oxidation-Reduction , Oxygenases/metabolism
9.
ACS Appl Mater Interfaces ; 15(17): 20726-20741, 2023 May 03.
Article in English | MEDLINE | ID: mdl-37088945

ABSTRACT

Radiation-induced bone injury management remains a challenge in clinical practice, and there is no effective medicine. Recently, biomass-derived carbon dots (CDs) have attracted attention in biomedical engineering due to the advantages of abundant heteroatoms, low toxicity, and no need to drug loading. Here, we report that CDs, synthesized from Lycium barbarum via hydrothermal strategy, can effectively alleviate radiation-induced bone injury. CCK-8, apoptosis analysis, ß-galactosidase staining, quantitative polymerase chain reaction, and western blots demonstrate that CDs can mediate radiation-induced damage and senescence of bone marrow mesenchymal stem cells (BMSCs). CDs regulate osteogenic- and adipogenic-balance after irradiation, shown by alizarin red and oil red O staining. In vivo experiments reveal that CDs prevent the occurrence of osteoradionecrosis in rats, demonstrated by micro-CT and histology examination. The osseointegration of titanium implants installed in irradiated bone is promoted by CDs. Mechanistically, CDs increase the N6-methyladenosine (m6A) level of irradiated BMSCs via the increased methyltransferase-like 3 (METTL3). High-throughput sequencing facilitates detection of increased m6A levels located in the 3'-untranslated regions (UTR) of the CAP-Gly domain containing linker protein 3 (Clip3) mRNA. The dual-luciferase reporter assay shows that 3'UTR is the direct target of METTL3. Subsequently, the increased m6A modification led to enhanced degradation of mRNA and downregulated CLIP3 expression, eventually resulting in the alleviation of radiation-induced bone injury. Interfering with the METTL3/Clip3 axis can antagonize the effect of CDs, indicating that CDs mediate radiation-induced bone injury via the METTL3/Clip3 axis. Taken together, CDs from L. barbarum alleviate radiation-induced bone injury by inhibiting senescence via regulation of m6A modification of Clip3. The present study paves a new pathway for the management of radiation-induced bone injury.


Subject(s)
Lycium , Radiation Injuries , Rats , Animals , Carbon , Bone and Bones/metabolism , Osteogenesis , RNA, Messenger/metabolism
10.
World J Clin Cases ; 11(9): 2074-2083, 2023 Mar 26.
Article in English | MEDLINE | ID: mdl-36998945

ABSTRACT

BACKGROUND: Infarction of the conus medullaris is a rare form of spinal cord infarction. The first symptom is usually acute non-characteristic lumbar pain, followed by lower limb pain, saddle numbness, fecal incontinence, and sexual dysfunction. Spontaneous conus infarction with "snake-eye appearance" on magnetic resonance imaging has rarely been reported. CASE SUMMARY: We report a 79-year-old male patient with spontaneous conus infarction who had acute lower extremity pain and dysuria as the first symptoms. He did not have any recent history of aortic surgery and trauma. Magnetic resonance imaging revealed a rare "snake-eye appearance." In addition, we reviewed the literature on 23 similar cases and summarized the clinical features and magnetic resonance manifestations of common diseases related to the "snake-eye sign" to explore the etiology, imaging findings, and prognosis of spontaneous conus infarction. CONCLUSION: We conclude that acute onset of conus medullaris syndrome combined with "snake-eye appearance" should be strongly suspected as conus medullaris infarction caused by anterior spinal artery ischemia. This special imaging manifestation is helpful in the early diagnosis and treatment of conus infarction.

11.
J Phys Chem B ; 127(1): 95-103, 2023 01 12.
Article in English | MEDLINE | ID: mdl-36525303

ABSTRACT

Understanding the general mechanism of the metal-free and cofactor-free oxidases and oxygenases catalyzed activation of triplet O2 is one of the most challenging questions in the field of enzymatic catalysis. Herein, we have performed Quantum Mechanics/Molecular Mechanics (QM/MM) multiscale simulations to reveal the detailed mechanism of the HOD catalyzed (i.e., 1-H-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase from Arthrobacter nitroguajacolicus Rü61a) decomposition of N-heteroaromatic compounds. The complete catalytic mechanism includes four steps: (1) proton transfer from 1-H-3-hydroxy-4-oxoquinaldine (QND) substrate to His251 residue coupled with an electron transfer from QND to triplet O2 (i.e., PCET), (2) formation of C-O bond via an open-shell singlet diradical recombination pathway, (3) ring-closure to form a bicyclic ring, and (4) dissociation of CO. The dissociation of CO is determined as the rate-limiting step, and its calculated energy barrier of 14.9 kcal/mol is consistent with the 15.5 kcal/mol barrier derived from experimental kinetic data. The mechanistic profile is not only valuable for understanding the fundamental pathway of cofactor-free oxidases and oxygenases-catalyzed reactions involving the triplet O2 activation but also discloses a new pathway that undergoes the processes of PCET and open-shell singlet transition state.


Subject(s)
Dioxygenases , Dioxygenases/chemistry , Protons , Electrons , Oxygenases , Catalysis
12.
BMC Plant Biol ; 22(1): 588, 2022 Dec 15.
Article in English | MEDLINE | ID: mdl-36522739

ABSTRACT

BACKGROUND: Sparganium (Typhaceae) is a widespread temperate genus of ecologically important aquatic plants. Previous reconstructions of the phylogenetic relationships among Sparganium species are incompletely resolved partly because they were based on molecular markers comprising < 7,000 bp. Here, we sequenced and assembled the complete chloroplast genomes from 19 Sparganium samples representing 15 putative species and three putative subspecies in order to explore chloroplast genome evolution in this genus, clarify taxonomic lineages, estimate the divergence times of Sparganium species, and reconstruct aspects of the biogeographic history of the genus. RESULTS: The 19 chloroplast genomes shared a conserved genome structure, gene content, and gene order. Our phylogenomic analysis presented a well-resolved phylogeny with robust support for most clades. Non-monophyly was revealed in three species: S. erectum, S. eurycarpum, and S. stoloniferum. Divergence time estimates suggest that the two subgenera of Sparganium split from each other ca. 30.67 Ma in the middle Oligocene. The subgenus Xanthosparganium diversified in the late Oligocene and Miocene, while the subgenus Sparganium diversified in the late Pliocene and Pleistocene. Ancestral area reconstruction suggested that the two subgenera may have originated in East Eurasia and North America. CONCLUSION: The non-monophyletic nature of three putative species underscores the necessity of taxonomic revision for Sparganium: S. stoloniferum subsp. choui may be more appropriately identified as S. choui, and subspecies of S. erectum may be in fact distinct species. The estimated diversification times of the two subgenera correspond to their species and nucleotide diversities. The likely ancestral area for most of subgenus Xanthosparganium was East Eurasia and North America from where it dispersed into West Eurasia and Australia. Most of subgenus Sparganium likely originated in North America and then dispersed into Eurasia. Our study demonstrates some of the ways in which complete chloroplast genome sequences can provide new insights into the evolution, phylogeny, and biogeography of the genus Sparganium.


Subject(s)
Genome, Chloroplast , Typhaceae , Phylogeny , Genome, Chloroplast/genetics , Phylogeography , North America
13.
Nanoscale ; 14(32): 11664-11675, 2022 Aug 18.
Article in English | MEDLINE | ID: mdl-35912901

ABSTRACT

Direct Z-scheme photocatalytic systems are very promising composite photocatalysts, and their photocatalytic performance is highly associated with the quality of the interface within them. Herein, a novel direct Z-scheme heterojunction with a coherent interface has been presented for the first time. Specifically, the heterojunction was constructed by dispersing pre-prepared BiVO4 crystals into the reaction system to synthesize Cu3SnS4, followed by a hydrothermal reaction. It is shown that Cu3SnS4 was deposited on the surface of each pre-prepared BiVO4 crystal as a thin layer via heterogeneous nucleation to acquire a core-shell heterojunction. The BiVO4@Cu3SnS4 heterojunction was found to possess an atomic coherent interface, which is formed through the bonding between the (121) plane of BiVO4 and the (112) plane of Cu3SnS4, originating from the matching in the crystalline lattice between the two planes. The coherent interface facilitated the charge transfer from Cu3SnS4 to BiVO4 owing to the difference in their Fermi levels, thereby forming a built-in electric field pointing from Cu3SnS4 to BiVO4. Reduced fluorescence emission and a shortened carrier lifetime reveal an obvious reduction in the inter-band charge recombination for the optimal BVO@CTS-0.19 sample. Consequently, BVO@CTS-0.19 shows remarkably enhanced photocatalytic performance in MO degradation, Cr6+ reduction and oxygen evolution. The Z-scheme charge transfer mechanism for BVO@CTS-0.19 was verified by a suite of techniques. This work provides a universal strategy for building a coherent interface to develop high-performance direct Z-scheme heterojunctions.

14.
Org Biomol Chem ; 20(28): 5525-5534, 2022 07 20.
Article in English | MEDLINE | ID: mdl-35786703

ABSTRACT

Uncovering the comprehensive catalytic mechanism for the activation of triplet O2 through metal-free and cofactor-free oxidases and oxygenases remains one of the most challenging problems in the area of enzymatic catalysis. Herein, we performed multiscale simulation with molecular dynamics (MD) and quantum mechanics/molecular mechanics (QM/MM) techniques to reveal the detailed mechanism of ActVA-Orf6 monooxygenase catalyzed oxygenation of phenols to quinones from Streptomyces coelicolor, such as the oxidation of 6-deoxydihydrocarafungin (DDHK) to dihydrocarafungin (DHK). The entire catalytic mechanism consists of three steps: (1) proton-coupled electron transfer (PCET) from the substrate DDHK to triplet O2 with the aid of an explicit water molecule, (2) the formation of a C-O bond via an open-shell singlet diradical complexation pathway, and (3) dehydration via a six-membered ring mode assisted by one water molecule. The complete energetic profiles show that the rate-determining step is the dehydration with an energy barrier of 20.7 kcal mol-1, which is close to that of 19.7 kcal mol-1 derived from experimental kinetic data. Our mechanistic study not only helps to deeply understand the fundamental mechanism of metal-free and cofactor-free oxidase and oxygenase catalyzed different reactions, but also discloses a new route that proceeds through the processes of PCET and the open-shell singlet transition state.


Subject(s)
Mixed Function Oxygenases , Protons , Catalysis , Dehydration , Electrons , Mixed Function Oxygenases/metabolism , Molecular Dynamics Simulation , Quantum Theory , Streptomyces coelicolor , Water
15.
Cell Mol Biol (Noisy-le-grand) ; 67(5): 81-87, 2022 Feb 04.
Article in English | MEDLINE | ID: mdl-35818268

ABSTRACT

LETMD1 is a differentially expressed gene selected by scientists from cervical cancer (CC) tissues by RT-PCR technology. It has been confirmed that LETMD1 is overexpressed in many human malignant tumors, so it can be used as an early diagnostic marker for malignant tumors and as a target for gene therapy. The purpose of this article is to further explore the effectiveness of miR-494 in inhibiting the proliferation, migration and invasion of CC cells by regulating LETMD1, selecting 40 cases of CC admitted to a hospital from June 2015 to September 2018 Patients, tumor tissue specimens were taken from the primary tumor tissue of CC, and normal tissues near the cutting edge were collected as controls. Normal tissues were confirmed by pathology after surgery that they were not invaded by cancer tissues. The results of the study showed that the expression level of miR-494 increased by 15%, and the prognostic survival rate after surgery increased by 20%, depending on gender, age, tumor size, and tumor site. After high expression of miR-494 in CC patients, the vascular invasion of CC cells was reduced by 33%, and distant metastasis was reduced by 11%, and the survival time of patients was significantly prolonged. After the expression of LETMD1, the proportion of cancer cells decreased by 5%, the proportion of macrophages increased by 2%, and the dendritic cells increased by 3%.


Subject(s)
MicroRNAs , Proto-Oncogene Proteins , Uterine Cervical Neoplasms , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Female , Gene Expression Regulation, Neoplastic , Humans , MicroRNAs/genetics , Proto-Oncogene Proteins/genetics , Uterine Cervical Neoplasms/genetics , Uterine Cervical Neoplasms/pathology
16.
J Colloid Interface Sci ; 625: 680-691, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35764047

ABSTRACT

Photocatalytic hydrogen peroxide (H2O2) production is a green process but remains a great challenge. Herein, a novel photocatalyst with high activity for H2O2 production, is developed based on 2,5,8-triamino-tri-s-triazine (melem) by linking it with 2, 3-naphthalene dicarboxylic anhydride (NDA). The obtained melem/NDA hybrid not only exhibited narrowed band gap and obviously enhanced visible light absorption, but also showed reduced charge recombination originated from its spatial distribution in HOMO and LUMO induced by the introduction of NDA as verified by DFT calculations. More significantly, the sufficient LUMO and HOMO positions for the optimal sample, melem/NDA0.5, ensured efficient H2O2 production from pure water via both the oxygen reduction reactions mainly through the two-step one-electron path and the water oxidation reaction through the one-step two-electron path. Consequently, melem/NDA0.5 achieves an apparent quantum efficiency of as high as 6.9 % at 420 nm. This work sheds light on developing high-performance organic photocatalysts for boosting photocatalytic H2O2 production.

17.
Adv Mater ; 34(26): e2202301, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35460143

ABSTRACT

Healing charge-selective contact interfaces in perovskite solar cells (PSCs) highly determines the power conversion efficiency (PCE) and stability. However, the state-of-the-art strategies are often static by one-off formation of a functional interlayer, which delivers fixed interfacial properties during the subsequent operation. As a result, defects formed in-service will gradually deteriorate the photovoltaic performances. Herein, a dynamic healing interface (DHI) is presented by incorporating a low-melting-point small molecule onto perovskite film surface for highly efficient and stable PSCs. Arising from the reduced non-radiative recombination, the DHI boosts the PCE to 12.05% for an all-inorganic CsPbIBr2 solar cell and 14.14% for a CsPbI2 Br cell, as well as 23.37% for an FA0.92 MA0.08 PbI3 (FA = formamidinium, MA = methylammonium) cell. The solid-to-liquid phase conversion of DHI at elevated temperature causes a longitudinal infiltration into the bulk perovskite film to maximize the charge extraction, passivate defects at grain boundaries, and suppress ion migration. Furthermore, the stability is remarkably enhanced under air, heat, and persistent light-irradiation conditions, paving a universal strategy for advanced perovskite-based optoelectronics.

18.
Sci Rep ; 12(1): 2812, 2022 02 18.
Article in English | MEDLINE | ID: mdl-35181685

ABSTRACT

This study aimed to explore the changes of the vaginal microbiota and enzymes in the women with high-risk human papillomavirus (HR-HPV) infection and cervical lesions. A total of 448 participants were carried out HPV genotyping, cytology tests, and microecology tests, and 28 participants were treated as sub-samples, in which vaginal samples were characterized by sequencing the bacterial 16S V4 ribosomal RNA (rRNA) gene region. The study found the prevalence of HR-HPV was higher in patients with BV (P = 0.036). The HR-HPV infection rate was 72.73% in G. vaginalis women, which was significantly higher than that of women with lactobacillus as the dominant microbiota (44.72%) (P = 0.04). The positive rate of sialidase (SNA) was higher in women with HR-HPV infection (P = 0.004) and women diagnosed with cervical intraepithelial neoplasia (CIN) (P = 0.041). In HPV (+) women, the α-diversity was significantly higher than that in HPV (-) women. The 16S rRNA gene-based amplicon sequencing results showed that Lactobacillus was the dominant bacteria in the normal vaginal microbiota. However, the proportion of Gardnerella and Prevotella were markedly increased in HPV (+) patients. Gardnerella and Prevotella are the most high-risk combination for the development of HPV (+) women. The SNA secreted by Gardnerella and Prevotella may play a significant role in HPV infection progress to cervical lesions.


Subject(s)
Microbiota/genetics , Papillomavirus Infections/microbiology , Uterine Cervical Dysplasia/microbiology , Vagina/microbiology , Alphapapillomavirus/genetics , Alphapapillomavirus/pathogenicity , Bacteria/classification , Bacteria/genetics , Female , Humans , Lactobacillus/genetics , Neuraminidase/genetics , Papillomavirus Infections/genetics , Papillomavirus Infections/pathology , Papillomavirus Infections/virology , RNA, Ribosomal, 16S/genetics , Vagina/virology , Uterine Cervical Dysplasia/genetics , Uterine Cervical Dysplasia/pathology , Uterine Cervical Dysplasia/virology
19.
Dalton Trans ; 51(8): 3046-3050, 2022 Feb 22.
Article in English | MEDLINE | ID: mdl-35133395

ABSTRACT

Density functional theory (DFT) calculations with 1-phenylselenylphosphirane complex 1 provide an insight into phosphirane fragmentation to phosphinidene complexes. FMO and ELF analyses show that the cleavage of two P-C σ bonds of phosphirane proceeds via an asynchronous concerted pathway. Transient [PhSeP-W(CO)5] was generated by dissociation of 1 at 90 °C and trapped with different reagents. The 1-phenoxylphosphirane complex undergoes [1 + 2] retroaddition at a comparatively higher temperature which implies that the lone pair of the adjacent atom center of phosphorus plays a major role in phosphirane fragmentation.

20.
Angew Chem Int Ed Engl ; 61(8): e202116632, 2022 Feb 14.
Article in English | MEDLINE | ID: mdl-34935265

ABSTRACT

One great challenge for perovskite solar cells (PSCs) lies in their poor operational stability under harsh stimuli by humidity, heat, light, etc. Herein, a thermal-triggered self-healing polyurethane (PU) is tailored to simultaneously improve the efficiency and stability of inorganic CsPbIBr2 PSCs. The dynamic covalent disulfide bonds between adjacent molecule chains in PU at high temperatures self-heal the in-service formed defects within the CsPbIBr2 perovskite film. Finally, the best device free of encapsulation achieves a champion efficiency up to 10.61 % and an excellent long-term stability in an air atmosphere over 80 days and persistent heat attack (85 °C) over 35 days. Moreover, the photovoltaic performances are recovered by a simple heat treatment.

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