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1.
Nature ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39236747

RESUMO

Two-terminal monolithic perovskite/silicon tandem solar cells demonstrate huge advantages in power conversion efficiency compared with their respective single-junction counterparts1,2. However, suppressing interfacial recombination at the wide-bandgap perovskite/electron transport layer interface, without compromising its superior charge transport performance, remains a substantial challenge for perovskite/silicon tandem cells3,4. By exploiting the nanoscale discretely distributed lithium fluoride ultrathin layer followed by an additional deposition of diammonium diiodide molecule, we have devised a bilayer-intertwined passivation strategy that combines efficient electron extraction with further suppression of non-radiative recombination. We constructed perovskite/silicon tandem devices on a double-textured Czochralski-based silicon heterojunction cell, which featured a mildly textured front surface and a heavily textured rear surface, leading to simultaneously enhanced photocurrent and uncompromised rear passivation. The resulting perovskite/silicon tandem achieved an independently certified stabilized power conversion efficiency of 33.89%, accompanied by an impressive fill factor of 83.0% and an open-circuit voltage of nearly 1.97 V. To the best of our knowledge, this represents the first reported certified efficiency of a two-junction tandem solar cell exceeding the single-junction Shockley-Queisser limit of 33.7%.

2.
Plant Cell ; 36(8): 2759-2777, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38447960

RESUMO

Cotton (Gossypium hirsutum) fibers, vital natural textile materials, are single-cell trichomes that differentiate from the ovule epidermis. These fibers are categorized as lint (longer fibers useful for spinning) or fuzz (shorter, less useful fibers). Currently, developing cotton varieties with high lint yield but without fuzz remains challenging due to our limited knowledge of the molecular mechanisms underlying fiber initiation. This study presents the identification and characterization of a naturally occurring dominant negative mutation GhMYB25-like_AthapT, which results in a reduced lint and fuzzless phenotype. The GhMYB25-like_AthapT protein exerts its dominant negative effect by suppressing the activity of GhMYB25-like during lint and fuzz initiation. Intriguingly, the negative effect of GhMYB25-like_AthapT could be alleviated by high expression levels of GhMYB25-like. We also uncovered the role of GhMYB25-like in regulating the expression of key genes such as GhPDF2 (PROTODERMAL FACTOR 2), CYCD3; 1 (CYCLIN D3; 1), and PLD (Phospholipase D), establishing its significance as a pivotal transcription factor in fiber initiation. We identified other genes within this regulatory network, expanding our understanding of the determinants of fiber cell fate. These findings offer valuable insights for cotton breeding and contribute to our fundamental understanding of fiber development.


Assuntos
Fibra de Algodão , Regulação da Expressão Gênica de Plantas , Gossypium , Mutação , Proteínas de Plantas , Gossypium/genética , Gossypium/metabolismo , Gossypium/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Mutação/genética , Fenótipo , Plantas Geneticamente Modificadas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
Plant Cell ; 35(5): 1455-1473, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-36748257

RESUMO

In most flowering plants, the female germline is initiated in the subepidermal L2 layer of ovule primordia forming a single megaspore mother cell (MMC). How signaling from the L1 (epidermal) layer could contribute to the gene regulatory network (GRN) restricting MMC formation to a single cell is unclear. We show that EPIDERMAL PATTERNING FACTOR-like (EPFL) peptide ligands are expressed in the L1 layer, together with their ERECTA family (ERf) receptor kinases, to control female germline specification in Arabidopsis thaliana. EPFL-ERf dependent signaling restricts multiple subepidermal cells from acquiring MMC-like cell identity by activating the expression of the major brassinosteroid (BR) receptor kinase BRASSINOSTEROID INSENSITIVE 1 and the BR-responsive transcription factor BRASSINOZOLE RESISTANT 1 (BZR1). Additionally, BZR1 coordinates female germline specification by directly activating the expression of a nucleolar GTP-binding protein, NUCLEOSTEMIN-LIKE 1 (NSN1), which is expressed in early-stage ovules excluding the MMC. Mutants defective in this GRN form multiple MMCs resulting in a strong reduction of seed set. In conclusion, we uncovered a ligand/receptor-like kinase-mediated signaling pathway acting upstream and coordinating BR signaling via NSN1 to restrict MMC differentiation to a single subepidermal cell.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Transdução de Sinais/genética , Proteínas de Transporte/metabolismo , Células Germinativas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Ligação a DNA/metabolismo
4.
Nature ; 577(7788): 79-84, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31853069

RESUMO

Water lilies belong to the angiosperm order Nymphaeales. Amborellales, Nymphaeales and Austrobaileyales together form the so-called ANA-grade of angiosperms, which are extant representatives of lineages that diverged the earliest from the lineage leading to the extant mesangiosperms1-3. Here we report the 409-megabase genome sequence of the blue-petal water lily (Nymphaea colorata). Our phylogenomic analyses support Amborellales and Nymphaeales as successive sister lineages to all other extant angiosperms. The N. colorata genome and 19 other water lily transcriptomes reveal a Nymphaealean whole-genome duplication event, which is shared by Nymphaeaceae and possibly Cabombaceae. Among the genes retained from this whole-genome duplication are homologues of genes that regulate flowering transition and flower development. The broad expression of homologues of floral ABCE genes in N. colorata might support a similarly broadly active ancestral ABCE model of floral organ determination in early angiosperms. Water lilies have evolved attractive floral scents and colours, which are features shared with mesangiosperms, and we identified their putative biosynthetic genes in N. colorata. The chemical compounds and biosynthetic genes behind floral scents suggest that they have evolved in parallel to those in mesangiosperms. Because of its unique phylogenetic position, the N. colorata genome sheds light on the early evolution of angiosperms.


Assuntos
Genoma de Planta , Nymphaea/genética , Filogenia , Flores/genética , Flores/metabolismo , Nymphaea/metabolismo , Odorantes/análise
5.
Plant Physiol ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39268871

RESUMO

The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated nuclease (Cas) system allows precise and easy editing of genes in many plant species. However, this system has not yet been applied to any fern species through gametophytes due to the complex characteristics of fern genomes, genetics, and physiology. Here, we established a protocol for gametophyte-based screening of single-guide RNAs (sgRNAs) with high efficiency for CRISPR/Cas9-mediated gene knockout in a model fern species, Ceratopteris richardii. We utilized the C. richardii ACTIN promoter to drive sgRNA expression and the enhanced CaMV 35S promoter to drive the expression of Streptococcus pyogenes Cas9 in this CRISPR-mediated editing system, which was employed to successfully edit a few genes, such as Nucleotidase/phosphatase 1 (CrSAL1) and Phytoene Desaturase (CrPDS), which resulted in an albino phenotype in C. richardii. Knockout of CrSAL1 resulted in significantly (P<0.05) reduced stomatal conductance (gs), leaf transpiration rate (E), guard cell length, and abscisic acid (ABA)-induced reactive oxygen species (ROS) accumulation in guard cells. Moreover, CrSAL1 overexpressing plants showed significantly increased net photosynthetic rate (A), gs, and E as well as most of the stomatal traits and ABA-induced ROS production in guard cells compared to the wild-type (WT) plants. Taken together, our optimized CRISPR/Cas9 system provides a useful tool for functional genomics in a model fern species, allowing the exploration of fern gene functions for evolutionary biology, herbal medicine discovery, and agricultural applications.

6.
Anal Chem ; 2024 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-39496189

RESUMO

A light-responsive covalent-organic framework (COF) nanozyme, which integrates the advantages of the COF structure and light-stimulated nanozyme catalysis, is a class of sensing star materials with wide application prospects. However, the sensing methods based on light-responsive COF nanozymes are relatively single at present. Therefore, it is necessary to develop new sensing strategies to broaden its application in chemical sensing and achieve highly efficient detection. Here, a Cu2+-modified COF composite material (TpDA-Cu) was rationally designed. The addition of Cu significantly inhibits the excellent light-responsive nanozyme activity of TpDA itself. However, because of the restoration of the enzyme activity by thiram (Tr) and the oxidase mimic activity of the newly formed Cu/Tr complex, TpDA-Cu/Tr exhibits stronger light-responsive nanozyme activity. Enzyme kinetic data show that compared with TpDA, TpDA-Cu/Tr has a larger Vmax value, which can achieve efficient catalytic oxidation of 3,3',5,5'-tetramethylbenzidine (TMB). In addition, the strong coordination effect of Tr and TpDA-Cu also plays a key role in achieving ultrafast, sensitive, and selective colorimetric detection of Tr. This work develops a dual activity regulation strategy of light-responsive COF nanozymes based on analyte induction and provides a new perspective for the application of light-responsive COF nanozymes in the field of sensing.

7.
Biochem Biophys Res Commun ; 731: 150360, 2024 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-39018970

RESUMO

Exercise is known to be an effective intervention for depression. NADPH has been demonstrated to have neuroprotective effects in our previous studies. This study aimed to investigate if NADPH has antidepressant effects and can mimic the effects of exercise in a chronic unpredictable stress (CUS) rat model. CUS rats underwent an 8-week swimming exercise (30 min/d, 5d/w) or were intraperitoneally administered 4 mg/kg or 8 mg/kg NADPH. The open field test (OFT), sucrose preference test (SPT), novelty-suppressed feeding test (NSFT), and forced swimming test (FST) were used to examine the antidepressant-like behaviors of the rats. Exercise, 4 mg/kg, and 8 mg/kg NADPH similarly reduced anxiety, as demonstrated by the number of fecal pellets. Meanwhile, exercise and 8 mg/kg NADPH significantly increased locomotion activity in the OFT. Exercise, 4 mg/kg, and 8 mg/kg NADPH effectively reversed CUS-induced anhedonia in rats in the SPT. Exercise, 4 mg/kg, and 8 mg/kg NADPH had no impact on appetite of depressed rats; however, 8 mg/kg NADPH increased the rats' exploratory activity in the NSFT. Exercise, 4 mg/kg, and 8 mg/kg NADPH significantly reduced the immobility time of CUS model rats, while exercise and 8 mg/kg NADPH postponed the early CUS-induced "immobility" in the FST. These results demonstrated that NADPH has similar antidepressant-like effects to exercise in CUS-induced depression model rats and is a potential exercise-mimicking antidepressant.


Assuntos
Antidepressivos , Depressão , Modelos Animais de Doenças , NADP , Condicionamento Físico Animal , Ratos Sprague-Dawley , Estresse Psicológico , Animais , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Masculino , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/fisiopatologia , NADP/metabolismo , Ratos , Depressão/tratamento farmacológico , Comportamento Animal/efeitos dos fármacos , Natação , Doença Crônica
8.
BMC Plant Biol ; 24(1): 626, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961401

RESUMO

BACKGROUND: The calmodulin (CaM) and calmodulin-like (CML) proteins play regulatory roles in plant growth and development, responses to biotic and abiotic stresses, and other biological processes. As a popular fruit and ornamental crop, it is important to explore the regulatory mechanism of flower and fruit development of passion fruit. RESULTS: In this study, 32 PeCaM/PeCML genes were identified from passion fruit genome and were divided into 9 groups based on phylogenetic analysis. The structural analysis, including conserved motifs, gene structure and homologous modeling, illustrates that the PeCaM/PeCML in the same subgroup have relative conserved structural features. Collinearity analysis suggested that the expansion of the CaM/CML gene family likely took place mainly by segmental duplication, and the whole genome replication events were closely related with the rapid expansion of the gene group. PeCaM/PeCMLs were potentially required for different floral tissues development. Significantly, PeCML26 had extremely high expression levels during ovule and fruit development compared with other PeCML genes, suggesting that PeCML26 had potential functions involved in the development of passion fruit flowers and fruits. The co-presence of various cis-elements associated with growth and development, hormone responsiveness, and stress responsiveness in the promoter regions of these PeCaM/PeCMLs might contribute to their diverse regulatory roles. Furthermore, PeCaM/PeCMLs were also induced by various abiotic stresses. This work provides a comprehensive understanding of the CaM/CML gene family and valuable clues for future studies on the function and evolution of CaM/CML genes in passion fruit. CONCLUSION: A total of 32 PeCaM/PeCML genes were divided into 9 groups. The PeCaM/PeCML genes showed differential expression patterns in floral tissues at different development stages. It is worth noting that PeCML26, which is highly homologous to AtCaM2, not only interacts with multiple BBR-BPC TFs, but also has high expression levels during ovule and fruit development, suggesting that PeCML26 had potential functions involved in the development of passion fruit flowers and fruits. This research lays the foundation for future investigations and validation of the potential function of PeCaM/PeCML genes in the growth and development of passion fruit.


Assuntos
Calmodulina , Flores , Frutas , Passiflora , Filogenia , Proteínas de Plantas , Passiflora/genética , Passiflora/crescimento & desenvolvimento , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Calmodulina/genética , Calmodulina/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Genes de Plantas , Perfilação da Expressão Gênica
9.
BMC Plant Biol ; 24(1): 895, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39343913

RESUMO

BACKGROUND: Glehnia littoralis F. Schmidt ex Miq., an endangered plant species with significant medicinal, edible, and ecological value, is now a central concern for conservation and sustainable utilization. Investigating the physiological and ecological mechanisms leading to its endangerment and elucidating its genetic background constitutes the foundation for conducting in-depth research on G. littoralis. RESULTS: Our observations have revealed a significant degree of floral sterility in wild populations of G. littoralis. The inflorescences of G. littoralis are classified into three types: completely fertile, completely sterile, and partially fertile compound umbels. Moreover, the flowers of G. littoralis can be categorized into fertile and sterile types. Sterile flowers exhibited abnormalities in the stigma, ovary, and ovules. This study is the first to discover that the presence or absence of a giant cell at the funiculus during the initiation of ovule primordium determines whether the flower can develop normally, providing cytological evidence for female sterility in G. littoralis. Conversely, both fertile and sterile flowers produced normally developed pollen. Field observations have suggested that robust plants bear more fertile umbels, while weaker ones have fewer or even no fertile umbels, indicating a close relationship between flower fertility and plant nutritional status. Our model correctly predicted that the eastern coastal regions of China, as well as prospective areas in Neimenggu and Sichuan, are suitable environments for its cultivation. Additionally, Using flow cytometry and genome survey, we estimated the genome size of G. littoralis to be 3.06 Gb and the heterozygosity to be 4.58%. CONCLUSION: The observations and findings presented in this study were expected to provide valuable insights for further conserving its genetic resources and sustainable utilization of G. littoralis.


Assuntos
Flores , Flores/crescimento & desenvolvimento , Flores/genética , Conservação dos Recursos Naturais , Genoma de Planta , Apiaceae/genética , Apiaceae/crescimento & desenvolvimento , Espécies em Perigo de Extinção , Infertilidade das Plantas/genética , China
10.
Plant Cell Environ ; 47(9): 3299-3315, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38757448

RESUMO

Global climate change is affecting plant photosynthesis and transpiration processes, as well as increasing weather extremes impacting socio-political and environmental events and decisions for decades to come. One major research challenge in plant biology and ecology is the interaction of photosynthesis with the environment. Stomata control plant gas exchange and their evolution was a crucial innovation that facilitated the earliest land plants to colonize terrestrial environments. Stomata couple homoiohydry, together with cuticles, intercellular gas space, with the endohydric water-conducting system, enabling plants to adapt and diversify across the planet. Plants control stomatal movement in response to environmental change through regulating guard cell turgor mediated by membrane transporters and signaling transduction. However, the origin, evolution, and active control of stomata remain controversial topics. We first review stomatal evolution and diversity, providing fossil and phylogenetic evidence of their origins. We summarize functional evolution of guard cell membrane transporters in the context of climate changes and environmental stresses. Our analyses show that the core signaling elements of stomatal movement are more ancient than stomata, while genes involved in stomatal development co-evolved de novo with the earliest stomata. These results suggest that novel stomatal development-specific genes were acquired during plant evolution, whereas genes regulating stomatal movement, especially cell signaling pathways, were inherited ancestrally and co-opted by dynamic functional differentiation. These two processes reflect the different adaptation strategies during land plant evolution.


Assuntos
Evolução Biológica , Mudança Climática , Estômatos de Plantas , Estômatos de Plantas/fisiologia , Adaptação Fisiológica , Plantas/genética , Plantas/metabolismo , Fenômenos Fisiológicos Vegetais
11.
J Exp Bot ; 75(3): 689-707, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-37864845

RESUMO

Environmental stresses severely affect plant growth and crop productivity. Regulated by 14-3-3 proteins (14-3-3s), H+-ATPases (AHAs) are important proton pumps that can induce diverse secondary transport via channels and co-transporters for the abiotic stress response of plants. Many studies demonstrated the roles of 14-3-3s and AHAs in coordinating the processes of plant growth, phytohormone signaling, and stress responses. However, the molecular evolution of 14-3-3s and AHAs has not been summarized in parallel with evolutionary insights across multiple plant species. Here, we comprehensively review the roles of 14-3-3s and AHAs in cell signaling to enhance plant responses to diverse environmental stresses. We analyzed the molecular evolution of key proteins and functional domains that are associated with 14-3-3s and AHAs in plant growth and hormone signaling. The results revealed evolution, duplication, contraction, and expansion of 14-3-3s and AHAs in green plants. We also discussed the stress-specific expression of those 14-3-3and AHA genes in a eudicotyledon (Arabidopsis thaliana), a monocotyledon (Hordeum vulgare), and a moss (Physcomitrium patens) under abiotic stresses. We propose that 14-3-3s and AHAs respond to abiotic stresses through many important targets and signaling components of phytohormones, which could be promising to improve plant tolerance to single or multiple environmental stresses.


Assuntos
Proteínas 14-3-3 , Arabidopsis , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Regulação da Expressão Gênica de Plantas , Plantas/genética , Plantas/metabolismo , Estresse Fisiológico/genética , Arabidopsis/genética , ATPases Translocadoras de Prótons/genética , Evolução Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
12.
Plant Cell ; 33(5): 1530-1553, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-33570655

RESUMO

The coordinated development of sporophytic and gametophytic tissues is essential for proper ovule patterning and fertility. However, the mechanisms regulating their integrated development remain poorly understood. Here, we report that the Swi2/Snf2-Related1 (SWR1) chromatin-remodeling complex acts with the ERECTA receptor kinase-signaling pathway to control female gametophyte and integument growth in Arabidopsis thaliana by inhibiting transcription of the microRNA gene MIR398c in early-stage megagametogenesis. Moreover, pri-miR398c is transcribed in the female gametophyte but is then translocated to and processed in the ovule sporophytic tissues. Together, SWR1 and ERECTA also activate ARGONAUTE10 (AGO10) expression in the chalaza; AGO10 sequesters miR398, thereby ensuring the expression of three AGAMOUS-LIKE (AGL) genes (AGL51, AGL52, and AGL78) in the female gametophyte. In the context of sexual organ morphogenesis, these findings suggest that the spatiotemporal control of miRNA biogenesis, resulting from coordination between chromatin remodeling and cell signaling, is essential for proper ovule development in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Montagem e Desmontagem da Cromatina/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , MicroRNAs/metabolismo , Óvulo Vegetal/crescimento & desenvolvimento , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , MicroRNAs/genética , Modelos Biológicos , Mutação/genética , Proteínas Serina-Treonina Quinases/genética , Receptores de Superfície Celular/genética , Fatores de Tempo , Transcrição Gênica
13.
Cancer Cell Int ; 24(1): 262, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39048994

RESUMO

BACKGROUND: This study investigated the molecular mechanism of long intergenic non-protein coding RNA 1605 (LINC01605) in the process of tumor growth and liver metastasis of pancreatic ductal adenocarcinoma (PDAC). METHODS: LINC01605 was filtered out with specificity through TCGA datasets (related to DFS) and our RNA-sequencing data of PDAC tissue samples from Renji Hospital. The expression level and clinical relevance of LINC01605 were then verified in clinical cohorts and samples by immunohistochemical staining assay and survival analysis. Loss- and gain-of-function experiments were performed to estimate the regulatory effects of LINC01605 in vitro. RNA-seq of LINC01605-knockdown PDAC cells and subsequent inhibitor-based cellular function, western blotting, immunofluorescence and rescue experiments were conducted to explore the mechanisms by which LINC01605 regulates the behaviors of PDAC tumor cells. Subcutaneous xenograft models and intrasplenic liver metastasis models were employed to study its role in PDAC tumor growth and liver metastasis in vivo. RESULTS: LINC01605 expression is upregulated in both PDAC primary tumor and liver metastasis tissues and correlates with poor clinical prognosis. Loss and gain of function experiments in cells demonstrated that LINC01605 promotes the proliferation and migration of PDAC cells in vitro. In subsequent verification experiments, we found that LINC01605 contributes to PDAC progression through cholesterol metabolism regulation in a LIN28B-interacting manner by activating the mTOR signaling pathway. Furthermore, the animal models showed that LINC01605 facilitates the proliferation and metastatic invasion of PDAC cells in vivo. CONCLUSIONS: Our results indicate that the upregulated lncRNA LINC01605 promotes PDAC tumor cell proliferation and migration by regulating cholesterol metabolism via activation of the mTOR signaling pathway in a LIN28B-interacting manner. These findings provide new insight into the role of LINC01605 in PDAC tumor growth and liver metastasis as well as its value for clinical approaches as a metabolic therapeutic target in PDAC.

14.
Langmuir ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39021159

RESUMO

Direct initiation of secondary explosives by a semiconductor laser is highly demanded, but it is challenging to exclude the use of sensitive primers. Most laser-sensitive energetic materials are usually mechanically sensitive. In order to reduce the mechanical sensitivity (MS) of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) while improving laser absorbance in the near-infrared band, spherical CL-20 composites (SCCs) embedded with nano aluminum (Al) powder and graphene-based catalyst (GO-CHZ-Co) were prepared by a spray drying method. These SCCs have been characterized comprehensively in terms of their morphologies, particle size distribution, laser absorbance, thermal decomposition behaviors, MS, and laser ignition properties. Results show that the maximum critical impact energy of SCCs was 3.8 J, which is 2.8 J higher than that of pristine ε-CL-20. The critical friction load was increased by at most 108 N compared to pristine CL-20. The absorbance has also been significantly increased up to almost 70% in the wavelength between 400 and 1400 nm, where the peak absorption is located in the region of 800-900 nm. In addition, the initial decomposition temperature (Ti) of SCCs is lower than that of pure CL-20, especially in the presence of GO-CHZ-Co. The apparent activation energy (Ea) for the decomposition of SCCs was largely dependent on the particle size of Al. Preliminary ignition tests indicate that the SCCs can be ignited successfully by a small-power laser.

15.
BMC Neurol ; 24(1): 280, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39127615

RESUMO

BACKGROUND: There has long been clinical disagreement over the resumption of antiplatelet therapy in patients with primary intracranial hemorrhage (ICH). This meta-analysis aimed to systematically evaluate the efficacy and safety of restarting antiplatelet therapy after ICH among different races and ethnicities. METHODS: All relevant medical studies involving adults with antiplatelet-associated ICH published in PubMed, The Cochrane Library and Chinese National Knowledge Infrastructure from inception to March 2024 were sourced. Outcome measures were thromboembolic events (stroke and myocardial infarction) and recurrence of ICH. After assessing study heterogeneity and publication bias, we performed a meta-analysis using random-effects model to assess the strength of association between resumption of antiplatelet therapy and our outcomes.The review was not registered and the review protocol was not prepared. RESULTS: Thirty-five studies were included, with 9758 ICH patients. Subgroup analysis revealed that restarting antiplatelet therapy was associated with a significantly higher risk of recurrence or aggravation of cerebral hemorrhage in Asians[OR = 1.48, 95% CI (1.13-1.94), P = 0.004]; in Caucasians, on the contrary, reinitiation of antiplatelet therapy was not associated with a significantly higher risk of recurrence or aggravation of cerebral hemorrhage [OR = 0.85, 95% CI (0.67-1.06), P = 0.149]. Reinitiation of antiplatelet therapy was associated with a significantly lower risk of cerebral infarction [OR = 0.61, 95% CI (0.39-0.96), P = 0.033]. Restarting antiplatelet therapy after cerebral hemorrhage was not associated with a higher incidence rate of mortality [OR = 0.79, 95% CI (0.57, 1.08), P = 0.138], myocardial infarction [OR = 2.40, 95%CI (0.53,10.79), P = 0.253], hemiparesis [OR = 0.38, 95%CI (0.03,4.81), P = 0.451], neurological deficit [OR = 0.86,95%CI(0.32,2.33),P = 0.766]. CONCLUSION: Reinstitution of antiplatelet therapy after ICH was associated with a lower risk of thromboembolic complications.Resumption of antiplatelet therapy was not associated with a higher incidence of cerebral hemorrhage in Caucasians, but may be associated with a higher risk of cerebral hemorrhage recurrence in Asian populations.


Assuntos
Hemorragias Intracranianas , Inibidores da Agregação Plaquetária , Humanos , Povo Asiático/etnologia , Etnicidade , Hemorragias Intracranianas/induzido quimicamente , Hemorragias Intracranianas/etnologia , Hemorragias Intracranianas/epidemiologia , Inibidores da Agregação Plaquetária/uso terapêutico , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/efeitos adversos , População Branca
16.
J Fluoresc ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780833

RESUMO

Survival and prognosis of patients with acute myocardial infarction (AMI) are highly dependent on rapid and accurate diagnosis of myocardial damage. Troponin T is the primary diagnostic biomarker and is widely used in clinical practice. Amplified luminescent proximity homogeneous assay (AlphaLISA) may provide a solution to rapidly detect a small amount of analyte through molecular interactions between special luminescent donor beads and acceptor bead. Here, a double-antibody sandwich assay was introduced into AlphaLISA for rapid detection for early diagnosis of AMI and disease staging evaluation. The performance of the assay was evaluated. The study found that the cTnT assay has a linear range of 48.66 to 20,000 ng/L with a limit of detection of 48.66 ng/L. In addition, the assay showed no cross-reactivity with other classic biomarkers of myocardial infarction and was highly reproducible with intra- and inter-batch coefficients of variation of less than 10%, notably, only 3 min was taken, which is particularly suitable for clinical diagnosis. These results suggest that our method can be conveniently applied in the clinic to determine the severity of the patient's condition.

17.
J Fluoresc ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39235654

RESUMO

We aim to develop an amplified luminescence proximity homogeneous assay (AlphaLISA) for quantification of trypsinogen-2 levels in human serum for the diagnosis of acute pancreatitis. Based on new amplified luminescence proximity homogeneity assay (AlphaLISA) method, carboxyl-modified donor and acceptor beads were coupled to capture and detection antibodies. A double antibody sandwich immunoassay was used to detect the concentration of trypsinogen-2 in serum. The method had good linearity (> 0.998). The intra - analysis precision was between 1.54% and 2.20% (< 10%), the inter-analysis precision was between 3.17% and 6.94% (< 15%), and the recovery was between 96.23% and 103.45%. The cross-reactivity of carbohydrate antigen 242 (CA242) and T-cell immunoglobulin mucin-3 (Tim-3) were 0.09% and 0.93%, respectively. The detection time only needed 15 min. The results of trypsinogen-2-AlphaLISA and time-resolved fluorescence immunoassay were consistent (ρ = 0.9019). In addition, serum trypsinogen-2 concentration in patients with acute pancreatitis [239.23 (17.83-807.58) ng/mL] was significantly higher than that in healthy controls [20.54 (12.10-39.73) ng/mL]. When the cut-off value was 35.38ng/mL, the sensitivity and specificity were 91.8% and 96.67%, and the positive detection rate was 91.80%. We have successfully established a trypsinogen-2-AlphaLISA method, which can promote the timely diagnosis of acute pancreatitis.

18.
Phys Chem Chem Phys ; 26(42): 26966-26975, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39421930

RESUMO

The ultraviolet (UV) photodissociation dynamics of the 2-buten-2-yl (C4H7) radical were studied using the high-n Rydberg atom time-of-flight (HRTOF) technique in the photolysis region of 226-246 nm. 2-Buten-2-yl radicals were generated by 193 nm photodissociation of the precursor 2-chloro-2-butene. The H-atom photofragment yield (PFY) spectrum of 2-buten-2-yl is broad, peaking at 234 nm. Quantum chemistry calculations show that the UV absorption is due to the 3py and 3px Rydberg states (parallel to the plane of CC double bond). The translational energy distributions of the H-atom loss product channel, P(ET)'s, of 2-buten-2-yl show a bimodal distribution indicating two dissociation pathways. The major pathway peaks at ET ∼ 7 kcal mol-1 with a nearly constant fraction of average ET in the total excess energy, 〈fT〉, at ∼0.11-0.12. This main pathway has an isotropic product angular distribution with ß âˆ¼ 0, consistent with the unimolecular dissociation of a hot 2-buten-2-yl radical following internal conversion from the electronically excited state, resulting in the formation of 2-butyne + H (∼84%) and 1,2-butadiene + H (∼16%). Additionally, there is a minor non-statistical pathway with an isotropic angular distribution. The minor pathway peaks at ET ∼ 35 kcal mol-1 in the P(ET) distributions and exhibits a large 〈fT〉 of ∼0.40-0.46. This fast pathway suggests a direct dissociation of the methyl H-atom on a repulsive excited state surface or on the repulsive part of the ground state surface, forming 1,2-butadiene + H. The fast/slow pathway branching ratio is in the range of 0.03-0.08.

19.
J Phys Chem A ; 128(28): 5556-5566, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38953902

RESUMO

The ultraviolet (UV) photodissociation dynamics of the 1-methylallyl (1-MA) radical were studied using the high-n Rydberg atom time-of-flight (HRTOF) technique in the wavelength region of 226-244 nm. The 1-MA radicals were produced by 193 nm photodissociation of the 3-chloro-1-butene and 1-chloro-2-butene precursor. The 1 + 1 REMPI spectrum of 1-MA agrees with the previous UV absorption spectrum in this wavelength region. Quantum chemistry calculations show that the UV absorption is mainly attributed to the 3pz Rydberg state (perpendicular to the allyl plane). The H atom photofragment yield (PFY) spectrum of 1-MA from 3-chloro-1-butene displays a broad peak around 230 nm, while that from 1-chloro-2-butene peaks at ∼236 nm. The translational energy distributions of the H atom loss product channel, P (ET)'s, show a bimodal distribution indicating two dissociation pathways in 1-MA. The major pathway is isotropic in product angular distribution with ß âˆ¼ 0 and has a low fraction of average translational energy in the total excess energy, ⟨fT⟩, in the range of 0.13-0.17; this pathway corresponds to unimolecular dissociation of 1-MA after internal conversion to form 1,3-butadiene + H. The minor pathway is anisotropic with ß âˆ¼ -0.23 and has a large ⟨fT⟩ of ∼0.62-0.72. This fast pathway suggests a direct dissociation of the methyl H atom on a repulsive excited state surface or the repulsive part of the ground state surface to form 1,3-butadiene + H. The fast/slow pathway branching ratio is in the range of 0.03-0.08.

20.
Blood Purif ; 53(5): 386-395, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38194932

RESUMO

INTRODUCTION: Insufficient withdrawal duration of antithrombotics leads to excessive bleeding after major surgery. We hypothesize that intraoperative hemoadsorption (HA) can reduce postoperative allogeneic transfusion requirements and excessive bleeding events (EBE), without an increase in ischemic/thromboembolic events (ITE) in patients who have taken antithrombotics and undergone nonelective cardiac surgery. METHODS: A total of 460 patients admitted to our hospital from 2018 to 2022 were included in this study and divided into two groups: HA and non-HA. Because of the risk of bias due to differences in antithrombotic type, withdrawal duration, or basic coagulation function, propensity score matching was used for analyses. RESULTS: Out of 154 cases in the HA group, 144 pairs were successfully matched. No HA safety events such as hemolysis, hypotension, or device failure occurred. After matching, the two groups were found to be comparable in preoperative antithrombotic type, withdrawal duration, platelets and coagulation function, and demographic and perioperative characteristics. Although the HA group did not have a reduced incidence of EBE, this group exhibited significant decreases in the transfusion rate and volume, the incidence of ITE, acute kidney injury, and central nervous system injury. CONCLUSIONS: For patients who have undergone nonelective cardiac surgery and taken antithrombotics, HA can simply and safely rebalance the postoperative coagulation system and have associations with reduced transfusion and postoperative ITE.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Fibrinolíticos , Humanos , Fibrinolíticos/uso terapêutico , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Transfusão de Sangue , Hemorragia/etiologia , Incidência , Sulfadiazina , Estudos Retrospectivos
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