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1.
Plant Mol Biol ; 114(5): 110, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39361185

RESUMO

Jasmonic acid (JA), an important plant hormone, plays a crucial role in defending against herbivorous insects. In this study, we have identified a new Bowman-Birk type protease inhibitor (BBTI) protein in maize that is regulated by the JA pathway and exhibits significant antifeedant activity, which is notably induced by exogenous Methyl Jasmonate and Ostrinia furnacalis feeding treatments. Bioinformatics analysis revealed significant differences in the BBTI protein among different maize inbred lines, except for the conserved domain. Prokaryotic and eukaryotic expression systems were constructed and expressed, and combined with bioassays, it was demonstrated that the antifeedant activity of BBTI is determined by protein modifications and conserved domains. Through RT-qPCR detection of BBTI and JA regulatory pathway-related genes' temporal expression in different maize inbred lines, we identified the regulatory mechanism of BBTI synthesis under the JA pathway. This study successfully cloned and identified the MeJA-induced anti-feedant activity gene BBTI and conducted functional validation in different maize inbred lines, providing valuable insights into the response mechanism of insect resistance induced by the plant JA pathway. The increased expression of the anti-feedant activity gene BBTI through exogenous MeJA induction may offer a potential new strategy for mediating plant defense against Lepidoptan insects.


Assuntos
Acetatos , Ciclopentanos , Regulação da Expressão Gênica de Plantas , Mariposas , Oxilipinas , Proteínas de Plantas , Zea mays , Zea mays/genética , Zea mays/efeitos dos fármacos , Zea mays/metabolismo , Zea mays/parasitologia , Oxilipinas/farmacologia , Oxilipinas/metabolismo , Ciclopentanos/farmacologia , Ciclopentanos/metabolismo , Animais , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Acetatos/farmacologia , Mariposas/efeitos dos fármacos , Mariposas/fisiologia , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Inibidores de Proteases/farmacologia , Inibidores de Proteases/metabolismo , Herbivoria , Sequência de Aminoácidos , Filogenia
2.
J Am Chem Soc ; 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39475552

RESUMO

The chemistry of the Meisenheimer complexes is of fundamental interest in organic chemistry. While the nitro group has been extensively employed to facilitate the formation and stabilization of Meisenheimer complexes, the analogous application of more user-friendly ester groups has remained an unexplored frontier. Herein, we report ester-stabilized Meisenheimer complexes, which have remarkable air-, moisture-, and thermo-stability. Moreover, the isolable and well-defined Meisenheimer intermediates exhibit divergent reactivity for dearomatization reactions, including modular 1,4-additions, dearomative (2 + 3) cycloadditions, and even higher-order (4 + n) cycloadditions. These methodologies enabled rapid access to complicated cyclohexane derivatives with multiple all-carbon quaternary centers and interesting structure topologies.

3.
Br J Cancer ; 130(9): 1517-1528, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38459187

RESUMO

BACKGROUND: Circß-catenin, our first reported circRNA, has been reported to mediate tumorigenesis in various cancers. However, its biological functions and underlying mechanisms in colorectal cancer (CRC) remain unknown. METHODS: The qRT-PCR examination was used to detect the expression of circß-catenin, miR-197-3p, and CTNND1 in cells and human tissues. Western blot was conducted to detect the protein expression levels. The biological function of circß-catenin was verified by MTT, colony formation, wound healing, and transwell assays. The in vivo effects of circß-catenin were verified by nude mice xenograft and metastasis models. The regulatory network of circß-catenin/miR-197-3p/CTNND1 was confirmed via dual-luciferase reporter and RIP assays. RESULTS: In the present study, circß-catenin was found to promote CRC cell proliferation and metastasis in vitro and in vivo. Mechanistically, circß-catenin served as miRNA decoy to directly bind to miR-197-3p, then antagonized the repression of the target gene CTNND1, and eventually promoted the malignant phenotype of CRC. More interestingly, the inverted repeated Alu pairs termed AluJb1/2 and AluY facilitated the biogenesis of circß-catenin, which could be partially reversed by EIF4A3 binding to Alu element AluJb2. CONCLUSIONS: Our findings illustrated a novel mechanism of circß-catenin in modulating CRC tumorigenesis and metastasis, which provides a potential therapeutic target for CRC patients.


Assuntos
Proliferação de Células , Neoplasias Colorretais , Progressão da Doença , Fator de Iniciação 4A em Eucariotos , Camundongos Nus , MicroRNAs , RNA Circular , beta Catenina , MicroRNAs/genética , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , RNA Circular/genética , Animais , Camundongos , beta Catenina/metabolismo , beta Catenina/genética , Proliferação de Células/genética , Fator de Iniciação 4A em Eucariotos/genética , Fator de Iniciação 4A em Eucariotos/metabolismo , delta Catenina , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Masculino , Feminino , Movimento Celular/genética , Camundongos Endogâmicos BALB C
4.
Anal Chem ; 96(5): 2117-2123, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38268109

RESUMO

Despite the progress that has been made in diverse DNA-based nanodevices to in situ monitor the activity of the DNA repair enzymes in living cells, the significance of improving both the sensitivity and specificity has remained largely neglected and understudied. Herein, we propose a regulatable DNA nanodevice to specifically monitor the activity of DNA repair enzymes for early evaluation of cancer mediated by genomic instability. Concretely, an AND logic gate-regulated DNAzyme nanoflower was rationally designed by the self-assembly of the DNA duplex modified with both apurinic/apyrimidinic (AP) site and methyl lesion site. The DNAzyme nanoflower could be reconfigured under the repair of AP sites and O6-methylguanine sites by apurinic/apyrimidinic endonuclease 1 (APE1) and O6-methylguanine methyltransferase (MGMT) to produce a fluorescent signal, realizing the sensitive monitoring of the activity of APE1 and MGMT. Compared to the free DNAzyme duplex, the fluorescent response of the DNAzyme nanoflower increased by 60%, due to the effective enrichment of the DNA probes by the nanoflower structure. More importantly, we have demonstrated that the dual-enzyme activated strategy allows imaging of specific cancer cells in the AND logic gate manner using MCF-7 as a cancer cell model, improving the specificity of cancer cell imaging. This AND logic gate-regulated multifunctional DNAzyme nanoflower provides a simple tool for simultaneously visualizing multiple DNA repair enzymes, holding great potential in early clinical diagnosis and drug discovery.


Assuntos
Reparo do DNA , DNA Catalítico , Dano ao DNA , Enzimas Reparadoras do DNA/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , DNA/química
5.
Anal Chem ; 96(40): 15915-15923, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39324376

RESUMO

Accurate monitoring of base excision repair (BER) activity in cancer cells is critical for advancing the comprehension of DNA repair processes, gaining insights into cancer development, and guiding treatment strategies. However, current assay techniques for assessing BER activity in cancer cells face challenges due to the heterogeneous origins and diversity of BER enzymes. In this work, we present a highly reliable triple loop-interlocked DNA codec (GATED) that enables precise assessment of BER activity in cancer cells through signal amplification mediated by multienzyme orthogonal activation. The GATED device features a dumbbell-shaped DNA probe to encode two BER enzymes for BER-related signal conversion as well as two bound circular DNA to decode the apurinic/apyrimidinic sites for apurinic/apyrimidinic endonuclease 1 (APE1)-mediated signal amplification. Importantly, GATED is orthogonally activated by multiple target BER enzymes (i.e., uracil DNA glycosylase, thymine DNA glycosylase, and APE1), resulting in a unified fluorescent signal that significantly improves the detection specificity and sensitivity to BER enzymes. Additionally, we demonstrate that the GATED has exceptional biostability within complex biological systems, where it was successfully employed to monitor BER activity in cancer cells with high specificity and enabled cell-based high-throughput screening for BER inhibitors. The GATED provides a much-needed tool for the real-time monitoring of BER activity and the screening of BER inhibitors in cancer cells, potentially advancing both the investigation and clinical application of BER biology.


Assuntos
Reparo do DNA , Humanos , DNA/química , DNA/metabolismo , Neoplasias/diagnóstico por imagem , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Linhagem Celular Tumoral , Imagem Óptica , Reparo por Excisão
6.
BMC Plant Biol ; 24(1): 152, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38418954

RESUMO

BACKGROUND: Due to being rooted in the ground, maize (Zea mays L.) is unable to actively escape the attacks of herbivorous insects such as the Asian corn borer (Ostrinia furnacalis). In contrast to the passive damage, plants have evolved defense mechanisms to protect themselves from herbivores. Salicylic acid, a widely present endogenous hormone in plants, has been found to play an important role in inducing plant resistance to insects. In this study, we screened and identified the insect resistance gene SPI, which is simultaneously induced by SA and O. furnacalis feeding, through preliminary transcriptome data analysis. The functional validation of SPI was carried out using bioinformatics, RT-qPCR, and heterologous expression protein feeding assays. RESULTS: Both SA and O. furnacalis treatment increased the expression abundance of SA-synthesis pathway genes and SPI in three maize strains, and the upregulation of SPI was observed strongly at 6 hours post-treatment. The expression of SPI showed a temporal relationship with SA pathway genes, indicating that SPI is a downstream defense gene regulated by SA. Protein feeding assays using two different expression vectors demonstrated that the variation in SPI protein activity among different strains is mainly due to protein modifications. CONCLUSIONS: Our research results indicate that SPI, as a downstream defense gene regulated by SA, is induced by SA and participates in maize's insect resistance. The differential expression levels of SPI gene and protein modifications among different maize strains are one of the reasons for the variation in insect resistance. This study provides new insights into ecological pest control in maize and valuable insights into plant responses to SA-induced insect resistance.


Assuntos
Mariposas , Zea mays , Animais , Zea mays/genética , Zea mays/metabolismo , Ácido Salicílico/farmacologia , Ácido Salicílico/metabolismo , Mariposas/genética , Insetos , Transcriptoma
7.
Small ; 20(33): e2307033, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38552219

RESUMO

Recently, aqueous zinc ion batteries (AZIBs) with the superior theoretical capacity, high safety, low prices, and environmental protection, have emerged as a contender for advanced energy storage. However, challenges related to cathode materials, such as dissolution, instability, and structural collapse, have hindered the progress of AZIBs. Here, a novel AZIB is constructed using an oxidized 2D layered MnBi2Te4 cathode for the first time. The oxidized MnBi2Te4 cathode with large interlayer spacing and low energy barrier for zinc ion diffusion at 240 °C, exhibited impressive characteristics, including a high reversibility capacity of 393.1 mAh g-1 (0.4 A g-1), outstanding rate performance, and long cycle stability. Moreover, the corresponding aqueous button cell also exhibits excellent electrochemical performance. To demonstrate the application in practice in the realm of flexible wearable electronics, a quasi-solid-state micro ZIB (MZIB) is constructed and shows excellent flexibility and high-temperature stability (the capacity does not significantly degrade when the temperature reaches 100 °C and the bending angle exceeds 150°). This research offers effective tactics for creating high-performance cathode materials for AZIBs.

8.
Small ; 20(29): e2400477, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38402438

RESUMO

Utilizing the ionic flux to generate voltage output has been confirmed as an effective way to meet the requirements of clean energy sources. Different from ionic thermoelectric (i-TE) and hydrovoltaic devices, a new hydrothermal chemical generator is designed by amorphous FeCl3 particles dispersing in MWCNT and unique ferric chloride or water gate. In the presence of gate, the special ion behaviors enable the cell to present a constant voltage of 0.60 V lasting for over 96 h without temperature difference. Combining the differences of cation concentration, humidity and temperature between the right and left side of sample, the maximum short-circuit current and power output can be obtained to 168.46 µA and 28.11 µW, respectively. The generator also can utilize the low-grade heat to produce electricity wherein Seebeck coefficient is 6.79 mV K-1. The emerged hydrothermal chemical generator offers a novel approach to utilize the low-grade heat, water and salt solution resources, which provides a simple, sustainable and low-cost strategy to realize energy supply.

9.
Small ; 20(13): e2305207, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37963824

RESUMO

2D perovskites have attracted tremendous attention due to their superior optoelectronic properties and potential applications in optoelectronic devices. Especially, the larger bandgap of 2D perovskite means that they are suitable for UV photodetection. However, the layered structure of 2D perovskites hinders the interlayer carrier transport, which limits the improvement of device performance. Therefore, nanoscale structures are normally used to enhance the light absorption ability, which is an effective strategy to improve the photocurrent in 2D perovskite-based photodetectors. Herein, a template-assisted low-temperature method is proposed to fabricate 2D perovskite ((C6H5C2H4NH3)2PbBr4, (PEA)2PbBr4) grating single crystal films (GSCFs). The crystallinity of the (PEA)2PbBr4 GSCFs is significantly improved due to the slow evaporation of the precursor solution under low temperatures. Based on this high crystalline quality and extremely ordered microstructures, the metal-semiconductor-metal photodetectors are assembled. Finite-different time-domain (FDTD) simulation and experiment indicate that the GSCF-based photodetectors exhibit significantly improved performance in comparison with the plane devices. The optimized 2D perovskite photodetectors are sensitive to UV light and demonstrate a responsivity and detectivity of 28.6 mA W-1 and 2.4 × 1011 Jones, respectively. Interestingly, the photocurrent of this photodetector varies as the angle of the incident polarized light, resulting in a high polarization ratio of 1.12.

10.
PLoS Pathog ; 18(9): e1010759, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36084159

RESUMO

Peste des petits ruminants virus (PPRV) is an important pathogen that seriously influences the productivity of small ruminants worldwide. PPRV is lymphotropic in nature and SLAM was identified as the primary receptor for PPRV and other Morbilliviruses. Many viruses have been demonstrated to engage extracellular vesicles (EVs) to facilitate their replication and pathogenesis. Here, we provide evidence that PPRV infection significantly induced the secretion levels of EVs from goat PBMC, and that PPRV-H protein carried in EVs can enhance SLAM receptor expression in the recipient cells via suppressing miR-218, a negative miRNA directly targeting SLAM gene. Importantly, EVs-mediated increased SLAM expression enhances PPRV infectivity as well as the expression of various cytokines related to SLAM signaling pathway in the recipient cells. Moreover, our data reveal that PPRV associate EVs rapidly entry into the recipient cells mainly through macropinocytosis pathway and cooperated with caveolin- and clathrin-mediated endocytosis. Taken together, our findings identify a new strategy by PPRV to enhance virus infection and escape innate immunity by engaging EVs pathway.


Assuntos
Vesículas Extracelulares , MicroRNAs , Peste dos Pequenos Ruminantes , Vírus da Peste dos Pequenos Ruminantes , Viroses , Animais , Caveolinas/metabolismo , Clatrina/metabolismo , Citocinas/metabolismo , Vesículas Extracelulares/metabolismo , Cabras/genética , Leucócitos Mononucleares , Ativação Linfocitária , MicroRNAs/genética , MicroRNAs/metabolismo , Vírus da Peste dos Pequenos Ruminantes/genética , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismo
11.
Plant Physiol ; 194(1): 243-257, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-37399189

RESUMO

Plant lignocellulosic biomass, i.e. secondary cell walls of plants, is a vital alternative source for bioenergy. However, the acetylation of xylan in secondary cell walls impedes the conversion of biomass to biofuels. Previous studies have shown that REDUCED WALL ACETYLATION (RWA) proteins are directly involved in the acetylation of xylan but the regulatory mechanism of RWAs is not fully understood. In this study, we demonstrate that overexpression of a Populus trichocarpa PtRWA-C gene increases the level of xylan acetylation and increases the lignin content and S/G ratio, ultimately yielding poplar woody biomass with reduced saccharification efficiency. Furthermore, through gene coexpression network and expression quantitative trait loci (eQTL) analysis, we found that PtRWA-C was regulated not only by the secondary cell wall hierarchical regulatory network but also by an AP2 family transcription factor HARDY (HRD). Specifically, HRD activates PtRWA-C expression by directly binding to the PtRWA-C promoter, which is also the cis-eQTL for PtRWA-C. Taken together, our findings provide insights into the functional roles of PtRWA-C in xylan acetylation and consequently saccharification and shed light on synthetic biology approaches to manipulate this gene and alter cell wall properties. These findings have substantial implications for genetic engineering of woody species, which could be used as a sustainable source of biofuels, valuable biochemicals, and biomaterials.


Assuntos
Populus , Populus/genética , Populus/metabolismo , Xilanos/metabolismo , Acetilação , Biomassa , Biocombustíveis/análise , Plantas/metabolismo , Parede Celular/metabolismo , Lignina/metabolismo
12.
Int Arch Allergy Immunol ; : 1-13, 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39471785

RESUMO

INTRODUCTION: Immunotherapy has demonstrated encouraging outcomes in tackling lung adenocarcinoma (LUAD), but immune escape may bring negative impacts. Only a single study has demonstrated the function of AIM2 in LUAD and reported that NF-κB and STAT1 are the chief transcription factors, this study is designed to analyze the role of AIM2 and examine the transcription factor, BATF in LUAD immunotherapy. METHODS: Bioinformatics methods to analyze the expression and binding sites of AIM2 and BATF in LUAD, as well as the correlation between AIM2 and PD-L1. Dual-luciferase and chromatin immunoprecipitation assays were used to verify the binding of AIM2 and BATF. qRT-PCR and Western blot assayed expression of AIM2, BATF, and PD-L1 in LUAD. MTT measured cell viability, flow cytometry detected cell apoptosis, cytotoxicity assays measured the toxicity of CD8+ T cells to cancer cells, and enzyme-linked immunosorbent assay measured the expression of related cytokines. Immunohistochemistry detected the protein expression levels of AIM2, BATF, PD-L1, and CD8 in tumor tissue. RESULTS: AIM2 and BATF were both highly expressed in LUAD, and there was a targeted binding relationship. BATF promoted LUAD cell proliferation and inhibited apoptosis by affecting AIM2 expression. The downregulation of AIM2 and PD-L1 expression inhibited PD-L1 and activated CD8+ T cells. The rescue experiment manifested that increased BATF weakened repression of AIM2 silencing on LUAD tumor immune escape in vitro and in vivo. CONCLUSION: BATF promoted AIM2 expression, upregulated PD-L1, inhibited CD8+ T cell activity, and ultimately led to immune escape in LUAD. Our research uncovered an innovative outlook on the intricate regulation of immune checkpoint molecules and proposed a new approach to target the BATF/AIM2 axis in tumor immunotherapy.

13.
Biotechnol Bioeng ; 121(3): 799-822, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38079153

RESUMO

The chemical modifications (CMs) of protein is an important technique in chemical biology, protein-based therapy, and material science. In recent years, there has been rapid advances in the development of CMs of peptides and proteins, providing new approaches for peptide and protein functionalization, as well as drug discovery. In this review, we highlight the methods for chemically modifying tyrosine (Tyr) residues in different regions, offering a comprehensive exposition of the research content related to Tyr modification. This review summarizes and provides an outlook on Tyr residue modification, aiming to offer readers assistance in the site-selective modification of macromolecules and to facilitate application research in this field.


Assuntos
Peptídeos , Tirosina , Peptídeos/química
14.
J Org Chem ; 89(15): 10603-10613, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-38990146

RESUMO

A Mn-catalyzed ligand-directed Csp3-Csp2 coupling of tertiary allylic alcohols with arylaldehydes has been developed. The method provides an efficient approach to access 1,5-diarylpent-1-en-3-ones via carbon-skeleton rearrangement-based aldol reaction.

15.
J Org Chem ; 89(6): 3684-3695, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38394358

RESUMO

A Rh(III)-catalyzed oxidative 1,3-aryl migration of α-arylallylic alcohols via Csp2-Csp3 σ bond activation has been developed. This method provides an efficient strategy to allow for allylic alcohol-based skeleton rearrangement, in which various secondary and tertiary α-arylallylic alcohols are rapidly converted to ß-aryl-α, ß-unsaturated ketones and aldehydes.

16.
Inorg Chem ; 63(1): 39-43, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38133832

RESUMO

A novel zinc phosphate derivative of Sr2Be2B2O7 (SBBO), K(NH4)Zn2(PO4)2 (KNZP), featuring [Zn2P2O8]∞2- double layers akin to the [Be2B2O7]∞4- layers in SBBO, was successfully synthesized via a moderate hydrothermal method. Through the substitution of BeO4 and BO3 with ZnO4 and PO4, the issue of toxicity has been effectively resolved, while the enhanced interlayer interactions facilitated by covalent and hydrogen bonding in KNZP overcome the inherent structural instability. Notably, KNZP exhibits a wide transparent window and a moderate second-harmonic generation (SHG) intensity, reaching 0.7 times that of KH2PO4 (KDP), rendering it type-I phase-matchable, indicating that it is a promising UV nonlinear optical (NLO) material.

17.
Environ Sci Technol ; 58(6): 2902-2911, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38294202

RESUMO

Conventional biological nutrient removal processes rely on external aeration and produce significant carbon dioxide (CO2) emissions. This study constructed a phototrophic simultaneous nitrification-denitrification phosphorus removal (P-SNDPR) system to treat low carbon to nitrogen (C/N) ratios wastewater and investigated the impact of sludge retention time (SRT) on nutrient removal performance, nitrogen conversion pathway, and microbial structure. Results showed that the P-SNDPR system at SRT of 15 days had the highest nutrient removal capacity, achieving over 85% and 98% removal of nitrogen and phosphorus, respectively, meanwhile maintaining minimal CO2 emissions. Nitrogen removal was mainly through assimilation at SRTs of 5 and 10 days, and nitrification-denitrification at SRTs of 15 and 20 days. Stable partial nitrification was facilitated by photoinhibition and low DO levels. Flow cytometry sorting technique results revealed SRT drove community structural changes in translational activity (BONCAT+) microbes, where BONCAT+ microbes were mainly simultaneous nitrogen and phosphorus removal bacteria (Candidatus Accumulibacter), denitrifying bacteria (Candidatus Competibacter and Plasticicumulans), ammonia-oxidizing bacteria (Nitrosomonas), and microalgae (Chlorella and Dictyosphaerium). The P-SNDPR system represents a novel, carbon-neutral process for efficient nutrient removal from low C/N ratio wastewater without aeration and external carbon source additions.


Assuntos
Chlorella , Águas Residuárias , Nitrificação , Desnitrificação , Fósforo/metabolismo , Nitrogênio/química , Nitrogênio/metabolismo , Dióxido de Carbono , Chlorella/metabolismo , Eliminação de Resíduos Líquidos/métodos , Reatores Biológicos/microbiologia , Esgotos/microbiologia
18.
Thromb J ; 22(1): 25, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38475817

RESUMO

BACKGROUND: The retrieval of inferior vena cava (IVC) filter is essential for preventing complications associated with the device. Advanced techniques have been developed to improve the success rate of retrieving tip-embedded filters. The forceps technique is frequently used to address this issue. CASE PRESENTATION: We present a case study of two patients who underwent a successful tip-embedded IVC filter retrieval using a modified forceps technique, which has not been previously reported. This technique involves using a wire loop under the filter tip and a forceps to grasp the filter shoulder. By pulling the wire loop and pushing the forceps in counterforce, the filter tip is straightened and aligned with the vascular sheath. The vascular sheath can then dissect the filter tip out from the caval wall and get inside the sheath to complete the retrieval. CONCLUSIONS: The modified forceps technique we present here offers a new solution for the complex retrieval of IVC filters.

19.
Phys Chem Chem Phys ; 26(9): 7695-7705, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38372167

RESUMO

The determination of impact sensitivity of energetic materials traditionally relies on expensive and safety-challenged experimental means. This has instigated a shift towards scientific computations to gain insights into and predict the impact response of energetic materials. In this study, we refine the phonon-vibron coupling coefficients ζ in energetic materials subjected to impact loading, building upon the foundation of the phonon up-pumping model. Considering the full range of interactions between high-order phonon overtones and molecular vibrational frequencies, this is a pivotal element for accurately determining phonon-vibron coupling coefficients ζ. This new coupling coefficient ζ relies exclusively on phonon and molecular vibrational frequencies within the range of 0-700 cm-1. Following a regression analysis involving ζ and impact sensitivity (H50) of 45 molecular nitroexplosives, we reassessed the numerical values of damping factors, establishing a = 2.5 and b = 35. This coefficient is found to be a secondary factor in determining sensitivity, secondary to the rate of decomposition propagation and thermodynamic factor (heat of explosion). Furthermore, the relationship between phonon-vibron coupling coefficients ζ and impact sensitivity was studied in 16 energetic crystalline materials and eight nitrogen-rich energetic salts. It was observed that as the phonon-vibron coupling coefficient increases, the tendency for reduced impact sensitivity H50 still exists.

20.
BMC Cardiovasc Disord ; 24(1): 435, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39160486

RESUMO

BACKGROUND: Currently, the treatment outcomes for complex congenital arteriovenous malformations (AVMs) remain unsatisfactory. This article reports on the utilization of an abdominal aortic stent graft, in conjunction with embolization techniques, for managing acute heart failure triggered by complex congenital arteriovenous malformations in the lower limb. CASE PRESENTATION: We present a case involving a patient with congenital AVMs in the lower limb, who had suffered from prolonged swelling in the left lower limb and recently developed symptoms of heart failure. At the age of 67, the patient was definitively diagnosed with a complex congenital AVMs in the lower limb. This article delves into the practical experiences and limitations encountered in employing an abdominal aortic stent graft, coupled with embolization, to address acute heart failure caused by complex congenital AVMs in the lower limb. CONCLUSIONS: Our article presents the initial report on the challenges and limitations encountered in treating acute heart failure triggered by complex congenital AVMs in the lower limb, utilizing a combination of abdominal aortic stent graft placement and embolization techniques.


Assuntos
Malformações Arteriovenosas , Embolização Terapêutica , Procedimentos Endovasculares , Insuficiência Cardíaca , Extremidade Inferior , Stents , Humanos , Embolização Terapêutica/instrumentação , Resultado do Tratamento , Malformações Arteriovenosas/terapia , Malformações Arteriovenosas/diagnóstico por imagem , Extremidade Inferior/irrigação sanguínea , Procedimentos Endovasculares/instrumentação , Insuficiência Cardíaca/terapia , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/etiologia , Idoso , Implante de Prótese Vascular/instrumentação , Masculino , Prótese Vascular , Feminino
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