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Photothermal heating and photocatalytic treatment are two solar-driven water processing approaches by harnessing NIR and UV-vis light, respectively, which can fully utilize solar energy if integrated. However, it remains a challenge to achieve high performance in both approaches when integrated in a material due to uncontrollable heat diffusion. Here, we report a demonstration of heat confinement on photothermal sites and fluid cooling on photocatalysis sites at the nanoscale, within a well-designed heat and fluid confinement nanofiber reactor. Photothermal and photocatalytic nanostructures were alternatively aligned in electrospun nanofibers for on-demand nanofluidic thermal management as well as easy folding into 3D structures with enhanced light utilization and mass transfer. Such a design showed simultaneously high photothermal evaporation rate (2.59 kg m-2 h-1, exceeding the limit rate) and efficient photocatalytic upcycling of microplastics pollutant into valued products. Enabled by controlled photothermal heating, the valued main product (i.e., methyl acetate) can be evaporated out with 100% selectivity by in situ separation.
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Structural variation of N-glycans is essential for the regulation of glycoprotein functions. GalNAcß1-4GlcNAc (LacdiNAc or LDN), a unique subterminal glycan structure synthesized by B4GALNT3 or B4GALNT4, is involved in the clearance of N-glycoproteins from the blood and maintenance of cell stemness. Such regulation of glycoprotein functions by LDN is largely different from that by the dominant subterminal structure, N-acetyllactosamine (Galß1-4GlcNAc, LacNAc). However, the mechanisms by which B4GALNT activity is regulated and how LDN plays different roles from LacNAc remain unclear. Here, we found that B4GALNT3 and four have unique domain organization containing a noncatalytic PA14 domain, which is a putative glycan-binding module. A mutant lacking this domain dramatically decreases the activity toward various substrates, such as N-glycan, O-GalNAc glycan, and glycoproteins, indicating that this domain is essential for enzyme activity and forms part of the catalytic region. In addition, to clarify the mechanism underlying the functional differences between LDN and LacNAc, we examined the effects of LDN on the maturation of N-glycans, focusing on the related glycosyltransferases upstream and downstream of B4GALNT. We revealed that, unlike LacNAc synthesis, prior formation of bisecting GlcNAc in N-glycan almost completely inhibits LDN synthesis by B4GALNT3. Moreover, the presence of LDN negatively impacted the actions of many glycosyltransferases for terminal modifications, including sialylation, fucosylation, and human natural killer-1 synthesis. These findings demonstrate that LDN has significant impacts on N-glycan maturation in a completely different way from LacNAc, which could contribute to obtaining a comprehensive overview of the system regulating complex N-glycan biosynthesis.
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N-Acetilgalactosaminiltransferases , Polissacarídeos , Humanos , Polissacarídeos/metabolismo , N-Acetilgalactosaminiltransferases/metabolismo , N-Acetilgalactosaminiltransferases/genética , Domínios Proteicos , Glicoproteínas/metabolismo , Glicoproteínas/genética , Glicoproteínas/química , Lactose/análogos & derivadosRESUMO
Recent genome-wide association studies have identified a missense variant p.A165T in mitochondrial amidoxime-reducing component 1 (mARC1) that is strongly associated with protection from all-cause cirrhosis and improved prognosis in nonalcoholic steatohepatitis. The precise mechanism of this protective effect is unknown. Substitution of alanine 165 with threonine is predicted to affect mARC1 protein stability and to have deleterious effects on its function. To investigate the mechanism, we have generated a knock-in mutant mARC1 A165T and a catalytically dead mutant C273A (as a control) in human hepatoma HepG2 cells, enabling characterization of protein subcellular distribution, stability, and biochemical functions of the mARC1 mutant protein expressed from its endogenous locus. Compared to WT mARC1, we found that the A165T mutant exhibits significant mislocalization outside of its traditional location anchored in the mitochondrial outer membrane and reduces protein stability, resulting in lower basal levels. We evaluated the involvement of the ubiquitin proteasome system in mARC1 A165T degradation and observed increased ubiquitination and faster degradation of the A165T variant. In addition, we have shown that HepG2 cells carrying the MTARC1 p.A165T variant exhibit lower N-reductive activity on exogenously added amidoxime substrates in vitro. The data from these biochemical and functional assays suggest a mechanism by which the MTARC1 p.A165T variant abrogates enzyme function which may contribute to its protective effect in liver disease.
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Proteínas Mitocondriais , Mutação de Sentido Incorreto , Humanos , Células Hep G2 , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Ubiquitinação , Estabilidade Proteica , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/genética , Proteólise , OxirredutasesRESUMO
Porcine epidemic diarrhea virus (PEDV) is a type A coronavirus that causes severe watery diarrhea in piglets, resulting in severe economic losses worldwide. Therefore, new approaches to control PEDV infection are essential for a robust and sustainable pig industry. We screened 314 small-molecule drug libraries provided by Selleck and found that four drugs had obviously inhibitory effects on PEDV in Vero cells. PA-824, which had the highest SI index and the most reliable clinical safety, was selected for in vivo experiments. Animal attack tests showed that PA-824 effectively alleviated the clinical signs, intestinal pathological changes, and inflammatory responses in lactating piglets after PEDV infection. To further investigate the antiviral mechanism of PA-824, we measured the inhibitory effect of PA-824 on PEDV proliferation in a dose-dependent manner. By exploring the effect of PA-824 on the PEDV life cycle, we found that PA-824 acted directly on viral particles and hindered the adsorption, internalization, and replication phases of the virus, followed by molecular docking analysis to predict the interaction between PA-824 and PEDV non-structural proteins. Finally, we found that PA-824 could inhibit the apoptotic signaling pathway by suppressing PEDV-induced p53 activation. These results suggest that PA-824 could be protective against PEDV infection in piglets and could be developed as a drug or a feed additive to prevent and control PEDV diseases.IMPORTANCEPEDV is a highly contagious enteric coronavirus that widely spread worldwide, causing serious economic losses. There is no drug or vaccine to effectively control PEDV. In this study, we found that PA-824, a compound of mycobacteria causing pulmonary diseases, inhibited PEDV proliferation in both in vitro and in vivo. We also found that PA-824 directly acted on viral particles and hindered the adsorption, internalization, and replication stages of the virus. In addition, we found that PA-824 could inhibit the apoptotic signaling pathway by inhibiting PEDV-induced p53 activation. In conclusion, it is expected to be developed as a drug or a feed additive to prevent and control PEDV diseases.
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Antivirais , Infecções por Coronavirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Proteína Supressora de Tumor p53 , Replicação Viral , Animais , Vírus da Diarreia Epidêmica Suína/efeitos dos fármacos , Vírus da Diarreia Epidêmica Suína/fisiologia , Células Vero , Suínos , Chlorocebus aethiops , Proteína Supressora de Tumor p53/metabolismo , Antivirais/farmacologia , Infecções por Coronavirus/virologia , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/tratamento farmacológico , Doenças dos Suínos/virologia , Doenças dos Suínos/tratamento farmacológico , Replicação Viral/efeitos dos fármacos , Simulação de Acoplamento Molecular , Apoptose/efeitos dos fármacosRESUMO
Many viruses inhibit general host gene expression to limit innate immune responses and gain preferential access to the cellular translational apparatus for their protein synthesis. This process is known as host shutoff. Influenza A viruses (IAVs) encode two host shutoff proteins: nonstructural protein 1 (NS1) and polymerase acidic X (PA-X). NS1 inhibits host nuclear pre-messenger RNA maturation and export, and PA-X is an endoribonuclease that preferentially cleaves host spliced nuclear and cytoplasmic messenger RNAs. Emerging evidence suggests that in circulating human IAVs NS1 and PA-X co-evolve to ensure optimal magnitude of general host shutoff without compromising viral replication that relies on host cell metabolism. However, the functional interplay between PA-X and NS1 remains unexplored. In this study, we sought to determine whether NS1 function has a direct effect on PA-X activity by analyzing host shutoff in A549 cells infected with wild-type or mutant IAVs with NS1 effector domain deletion. This was done using conventional quantitative reverse transcription polymerase chain reaction techniques and direct RNA sequencing using nanopore technology. Our previous research on the molecular mechanisms of PA-X function identified two prominent features of IAV-infected cells: nuclear accumulation of cytoplasmic poly(A) binding protein (PABPC1) and increase in nuclear poly(A) RNA abundance relative to the cytoplasm. Here we demonstrate that NS1 effector domain function augments PA-X host shutoff and is necessary for nuclear PABPC1 accumulation. By contrast, nuclear poly(A) RNA accumulation is not dependent on either NS1 or PA-X-mediated host shutoff and is accompanied by nuclear retention of viral transcripts. Our study demonstrates for the first time that NS1 and PA-X may functionally interact in mediating host shutoff.IMPORTANCERespiratory viruses including the influenza A virus continue to cause annual epidemics with high morbidity and mortality due to the limited effectiveness of vaccines and antiviral drugs. Among the strategies evolved by viruses to evade immune responses is host shutoff-a general blockade of host messenger RNA and protein synthesis. Disabling influenza A virus host shutoff is being explored in live attenuated vaccine development as an attractive strategy for increasing their effectiveness by boosting antiviral responses. Influenza A virus encodes two proteins that function in host shutoff: the nonstructural protein 1 (NS1) and the polymerase acidic X (PA-X). We and others have characterized some of the NS1 and PA-X mechanisms of action and the additive effects that these viral proteins may have in ensuring the blockade of host gene expression. In this work, we examined whether NS1 and PA-X functionally interact and discovered that NS1 is required for PA-X to function effectively. This work significantly advances our understanding of influenza A virus host shutoff and identifies new potential targets for therapeutic interventions against influenza and further informs the development of improved live attenuated vaccines.
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Vírus da Influenza A , Proteínas não Estruturais Virais , Humanos , Células A549 , Interações Hospedeiro-Patógeno , Vírus da Influenza A/genética , Influenza Humana/virologia , Influenza Humana/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/genética , Replicação Viral , Interações Hospedeiro-ParasitaRESUMO
Pulmonary arterial hypertension (PAH) is a progressive disease characterized by vasoconstriction and remodeling of small pulmonary arteries (PAs). Central to the remodeling process is a switch of pulmonary vascular cells to a proliferative, apoptosis-resistant phenotype. Plasminogen activator inhibitors-1 and -2 (PAI-1 and PAI-2) are the primary physiological inhibitors of urokinase-type and tissue-type plasminogen activators (uPA and tPA), but their roles in PAH are unsettled. Here, we report that: 1) PAI-1, but not PAI-2, is deficient in remodeled small PAs and in early-passage PA smooth muscle and endothelial cells (PASMCs and PAECs) from subjects with PAH compared with controls; 2) PAI-1-/- mice spontaneously develop pulmonary vascular remodeling associated with upregulation of mTORC1 signaling, pulmonary hypertension (PH), and right ventricle (RV) hypertrophy; and 3) pharmacological inhibition of uPA in human PAH PASMCs suppresses proproliferative mTORC1 and SMAD3 signaling, restores PAI-1 levels, reduces proliferation, and induces apoptosis in vitro, and prevents the development of SU5416/hypoxia-induced PH and RV hypertrophy in vivo in mice. These data strongly suggest that downregulation of PAI-1 in small PAs promotes vascular remodeling and PH due to unopposed activation of uPA and consequent upregulation of mTOR and transforming growth factor-ß (TGF-ß) signaling in PASMCs, and call for further studies to determine the potential benefits of targeting the PAI-1/uPA imbalance to attenuate and/or reverse pulmonary vascular remodeling and PH.NEW & NOTEWORTHY This study identifies a novel role for the deficiency of plasminogen activator inhibitor (PAI)-1 and resultant unrestricted uPA activity in PASMC remodeling and PH in vitro and in vivo, provides novel mechanistic link from PAI-1 loss through uPA-induced Akt/mTOR and TGFß-Smad3 upregulation to pulmonary vascular remodeling in PH, and suggests that inhibition of uPA to rebalance the uPA-PAI-1 tandem might provide a novel approach to complement current therapies used to mitigate this pulmonary vascular disease.
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Hipertensão Pulmonar , Músculo Liso Vascular , Inibidor 1 de Ativador de Plasminogênio , Remodelação Vascular , Animais , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Inibidor 1 de Ativador de Plasminogênio/genética , Humanos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Camundongos , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Transdução de Sinais , Masculino , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Proliferação de Células , Camundongos Knockout , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos Endogâmicos C57BL , Apoptose , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/genética , Hipertrofia Ventricular Direita/metabolismo , Hipertrofia Ventricular Direita/patologia , Hipertrofia Ventricular Direita/fisiopatologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Inibidor 2 de Ativador de Plasminogênio/metabolismo , Inibidor 2 de Ativador de Plasminogênio/genéticaRESUMO
BACKGROUND: After surgical resection of pancreatic ductal adenocarcinoma (PDAC), patients are predominantly treated with adjuvant chemotherapy, commonly consisting of gemcitabine (GEM)-based regimens or the modified FOLFIRINOX (mFFX) regimen. While mFFX regimen has been shown to be more effective than GEM-based regimens, it is also associated with higher toxicity. Current treatment decisions are based on patient performance status rather than on the molecular characteristics of the tumor. To address this gap, the goal of this study was to develop drug-specific transcriptomic signatures for personalized chemotherapy treatment. PATIENTS AND METHODS: We used PDAC datasets from preclinical models, encompassing chemotherapy response profiles for the mFFX regimen components. From them we identified specific gene transcripts associated with chemotherapy response. Three transcriptomic artificial intelligence signatures were obtained by combining independent component analysis and the least absolute shrinkage and selection operator-random forest approach. We integrated a previously developed GEM signature with three newly developed ones. The machine learning strategy employed to enhance these signatures incorporates transcriptomic features from the tumor microenvironment, leading to the development of the 'Pancreas-View' tool ultimately clinically validated in a cohort of 343 patients from the PRODIGE-24/CCTG PA6 trial. RESULTS: Patients who were predicted to be sensitive to the administered drugs (n = 164; 47.8%) had longer disease-free survival (DFS) than the other patients. The median DFS in the mFFX-sensitive group treated with mFFX was 50.0 months [stratified hazard ratio (HR) 0.31, 95% confidence interval (CI) 0.21-0.44, P < 0.001] and 33.7 months (stratified HR 0.40, 95% CI 0.17-0.59, P < 0.001) in the GEM-sensitive group when treated with GEM. Comparatively patients with signature predictions unmatched with the treatments (n = 86; 25.1%) or those resistant to all drugs (n = 93; 27.1%) had shorter DFS (10.6 and 10.8 months, respectively). CONCLUSIONS: This study presents a transcriptome-based tool that was developed using preclinical models and machine learning to accurately predict sensitivity to mFFX and GEM.
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Right ventricular failure (RVF) is a major cause of early mortality after heart transplantation (HT). Isoproterenol (Iso) has chronotropic, inotropic, and vasodilatory properties, which might improve right ventricle function in this setting. We aimed to investigate the hemodynamic effects of isoproterenol on patients with post-HT RVF. We conducted a 1-yr retrospective observational study including patients receiving isoproterenol (Iso) and dobutamine for early RVF after HT. A comprehensive multiparametric hemodynamic evaluation was performed successively three times: no isoproterenol, low doses: 0.025 µg/kg/min, and high doses: 0.05 µg/kg/min (henceforth, respectively, called no Iso, low Iso, and high Iso). From June 2022 to June 2023, 25 patients, median [interquartile range (IQR) 25-75] age 54 [38-61] yr, were included. Before isoproterenol was introduced, all patients received dobutamine, and 15 (60%) were on venoarterial extracorporeal membrane oxygenation (VA-ECMO). Isoproterenol significantly increased heart rate from 84 [77-99] (no Iso) to 91 [88-106] (low Iso) and 102 [90-122] beats/min (high Iso, P < 0.001). Similarly, cardiac index rose from 2.3 [1.4-3.1] to 2.7 [1.8-3.4] and 3 [1.9-3.7] L/min/m2 (P < 0.001) with a concomitant increase in indexed stroke volume (28 [17-34] to 31 [20-34] and 33 [23-35] mL/m2, P < 0.05). Effective pulmonary arterial elastance and pressures were not modified by isoproterenol. Pulmonary vascular resistance (PVR) tended to decrease from 2.9 [1.4-3.6] to 2.3 [1.3-3.5] wood units (WU), P = 0.06. Right ventricular ejection fraction/systolic pulmonary artery pressure (sPAP) evaluating right ventricle-pulmonary artery (RV-PA) coupling increased after isoproterenol from 0.8 to 0.9 and 1%·mmHg-1 (P = 0.001). In conclusion, in post-HT RVF, isoproterenol exhibits chronotropic and inotropic effects, thereby improving RV-PA coupling and resulting in a clinically relevant increase in the cardiac index.NEW & NOTEWORTHY This study offers a detailed and comprehensive hemodynamic investigation at the bedside, illustrating the favorable impact of isoproterenol on right ventricular-pulmonary arterial coupling and global hemodynamics. It elucidates the physiological effects of an underused inotropic strategy in a critical clinical scenario. By enhancing cardiac hemodynamics, isoproterenol has the potential to expedite right ventricular recovery and mitigate primary graft dysfunction, thereby reducing the duration of mechanical support and intensive care unit stay posttransplantation.
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Transplante de Coração , Hemodinâmica , Isoproterenol , Artéria Pulmonar , Disfunção Ventricular Direita , Função Ventricular Direita , Humanos , Isoproterenol/farmacologia , Transplante de Coração/efeitos adversos , Pessoa de Meia-Idade , Masculino , Artéria Pulmonar/fisiopatologia , Artéria Pulmonar/efeitos dos fármacos , Feminino , Função Ventricular Direita/efeitos dos fármacos , Estudos Retrospectivos , Adulto , Hemodinâmica/efeitos dos fármacos , Idoso , Disfunção Ventricular Direita/fisiopatologia , Disfunção Ventricular Direita/etiologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/tratamento farmacológico , Dobutamina/farmacologia , Resultado do Tratamento , Frequência Cardíaca/efeitos dos fármacos , Recuperação de Função Fisiológica , Cardiotônicos/farmacologiaRESUMO
Developing a new strategy to retain phosphoric acid (PA) to improve the performance and durability of high-temperature proton exchange membrane fuel cell (HT-PEMFC) remains a challenge. Here, a strategy for ion-restricted catcher microstructure that incorporates PA-doped multi-quaternized poly(fluorene alkylene-co-biphenyl alkylene) (PFBA) bearing confined nanochannels is reported. Dynamic analysis reveals strong interaction between side chains and PA molecules, confirming that the microstructure can improve PA retention. The PFBA linked with triquaternary ammonium side chain (PFBA-tQA) shows the highest PA retention rate of 95%. Its H2/O2 fuel cell operates within 0.6% voltage decay at 160 °C/0% RH, and it also runs over 100 h at 100 °C/49% RH under external humidification. This combination of high PA retention, and chemical and dimensional stability fills a gap in the HT-PEMFC field, which requires strict moisture control at 90-120 °C to prevent acid leaching, simplifying the start-up procedure of HT-PEMFC without preheating.
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Superhydrophobic fabrics with multiple functions have become a research hotspot. However, it is challenging to make self-healing mechanically robust and eco-friendly superhydrophobic fabrics, which are limited by complex fabrication processes and excessive use of environmentally unfriendly solvents during fabrication. Herein, inspired by the secretion of a waxy substance from the surface of lotus leaves to restore water repellency, self-healing superhydrophobic composite fabrics (as-synthesized PA66/6-PET@Tico) are obtained by constructing a papillary TiO2 and tentacle-like fluorinated acrylate polymer (FCB015) coating on polyester-nylon composite fabrics using two-step hydrothermal method. The result indicates that PA66/6-PET@Tico with hierarchical micro/nanostructure exhibits excellent superhydrophobic and self-healing properties. Compared with FCB015 coated fabric, the contact angles (CA) of water and soybean oil rise to 172.2° and 166.8° from 137.4° and 98.8°, respectively. After mechanical abrasion, PA66/6-PET@Tico recovers a water contact angle (WCA) of 165.6° at room temperature. The WCA remains higher than 155° after 18 h of chemical corrosion. Furthermore, the bacterial inhibition rates of PA66/6-PET@Tico for Staphylococcus Aureus and Escherichia Coli are 99.90 and 98.38%, respectively. In this work, a new idea is proposed for designing a simple and effective self-healing superhydrophobic coating, expecting to promote the large-scale industrial production and application of functional surfaces.
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Polyamines (PAs) are pleiotropic bioorganic molecules. Cellular PA contents are determined by a balance between PA synthesis and degradation. PAs have been extensively demonstrated to play vital roles in the modulation of plant developmental processes and adaptation to various environmental stresses. In this review, the latest advances on the diverse roles of PAs in a range of developmental processes, such as morphogenesis, organogenesis, growth and development, and fruit ripening, are summarized and discussed. Besides, the crosstalk between PAs and phytohormones or other signalling molecules, including H2O2 and NO, involved in these processes is dwelled on. In addition, the attempts made to improve the yield and quality of grain and vegetable crops through altering the PA catabolism are enumerated. Finally, several other vital questions that remain unanswered are proposed and discussed. These include the mechanisms underlying the cooperative regulation of developmental processes by PAs and their interplaying partners like phytohormones, H2O2 and NO; PA transport for maintaining homeostasis; and utilization of PA anabolism/catabolism for generating high-yield and good-quality crops. This review aims to gain new insights into the pleiotropic role of PAs in the modulation of plant growth and development, which provides an alternative approach for manipulating and engineering valuable crop varieties that can be used in the future.
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Starch utilization system (Sus)D-homologs are well known for their carbohydrate-binding capabilities and are part of the sus operon in microorganisms affiliated with the phylum Bacteroidota. Until now, SusD-like proteins have been characterized regarding their affinity toward natural polymers. In this study, three metagenomic SusD homologs (designated SusD1, SusD38489, and SusD70111) were identified and tested with respect to binding to natural and non-natural polymers. SusD1 and SusD38489 are cellulose-binding modules, while SusD70111 preferentially binds chitin. Employing translational fusion proteins with superfolder GFP (sfGFP), pull-down assays, and surface plasmon resonance (SPR) has provided evidence for binding to polyethylene terephthalate (PET) and other synthetic polymers. Structural analysis suggested that a Trp triad might be involved in protein adsorption. Mutation of these residues to Ala resulted in an impaired adsorption to microcrystalline cellulose (MC), but not so to PET and other synthetic polymers. We believe that the characterized SusDs, alongside the methods and considerations presented in this work, will aid further research regarding bioremediation of plastics. IMPORTANCE: SusD1 and SusD38489 can be considered for further applications regarding their putative adsorption toward fossil-fuel based polymers. This is the first time that SusD homologs from the polysaccharide utilization loci (PUL), largely described for the phylum Bacteroidota, are characterized as synthetic polymer-binding proteins.
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Proteínas de Bactérias , Bacteroidetes , Metagenoma , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bacteroidetes/genética , Bacteroidetes/metabolismo , Celulose/metabolismo , Polímeros/metabolismo , Quitina/metabolismo , Polietilenotereftalatos/metabolismoRESUMO
Photoacoustic (PA) tomography is an emerging biomedical imaging technology for precision cancer medicine. Conventional small-molecule PA probes usually exhibit a single PA signal and poor tumor targeting that lack the imaging reliability. Here, we introduce a series of cyanine/hemicyanine interconversion dyes (denoted Cy-HCy) for PA/fluorescent dual-mode probe development that features optimized ratiometric PA imaging and tunable tumor-targeting ability for precise diagnosis and resection of colorectal cancer (CRC). Importantly, Cy-HCy can be presented in cyanine (inherent tumor targeting and long NIR PA wavelength) and hemicyanine (poor tumor targeting and short NIR PA wavelength) by fine-tuning torsion angle and the ingenious transformation between cyanine and hemicyanine through regulation optically tunable group endows the NIR ratiometric PA and tunable tumor-targeting properties. To demonstrate the applicability of Cy-HCy dyes, we designed the first small-molecule tumor-targeting and NIR ratiometric PA probe Cy-HCy-H2S for precise CRC liver metastasis diagnosis, activated by H2S (a CRC biomarker). Using this probe, we not only visualized the subcutaneous tumor and liver metastatic cancers in CRC mouse models but also realized PA and fluorescence image-guided tumor excision. We expect that Cy-HCy will be generalized for creating a wide variety of inherently tumor-targeting NIR ratiometric PA probes in oncological research and practice.
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BACKGROUND: This study addresses the urgent need for infection control agents driven by the rise of drug-resistant pathogens such as Acinetobacter baumannii. Our primary aim was to develop and assess a novel endolysin, Tha-PA90, designed to combat these challenges. METHODS: Tha-PA90 incorporates an antimicrobial peptide (AMP) called thanatin at its N-terminus, enhancing bacterial outer membrane permeability and reducing host immune responses. PA90 was selected as the endolysin component. The antibacterial activity of the purified Tha-PA90 was evaluated using an in vitro colony-forming unit (CFU) reduction assay and a membrane permeability test. A549 cells were utilized to measure the penetration into the cytosol and the cytotoxicity of Tha-PA90. Finally, infection control was monitored in A. baumannii infected mice following the intraperitoneal administration of Tha-PA90. RESULTS: Tha-PA90 demonstrated remarkable in vitro efficacy, completely eradicating A. baumannii strains, even drug-resistant variants, at a low concentration of 0.5 µM. Notably, it outperformed thanatin, achieving only a < 3-log reduction at 4 µM. Tha-PA90 exhibited 2-3 times higher membrane permeability than a PA90 and thanatin mixture or PA90 alone. Tha-PA90 was found within A549 cells' cytosol with no discernible cytotoxic effects. Furthermore, Tha-PA90 administration extended the lifespan of A. baumannii-infected mice, reducing bacterial loads in major organs by up to 3 logs. Additionally, it decreased proinflammatory cytokine levels (TNF-α and IL-6), reducing the risk of sepsis from rapid bacterial lysis. Our findings indicate that Tha-PA90 is a promising solution for combating drug-resistant A. baumannii. Its enhanced efficacy, low cytotoxicity, and reduction of proinflammatory responses render it a potential candidate for infection control. CONCLUSIONS: This study underscores the significance of engineered endolysins in addressing the pressing challenge of drug-resistant pathogens and offers insights into improved infection management strategies.
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Infecções por Acinetobacter , Acinetobacter baumannii , Endopeptidases , Animais , Camundongos , Peptídeos Antimicrobianos , Peptídeos Catiônicos Antimicrobianos , Antibacterianos/farmacologia , Infecções por Acinetobacter/tratamento farmacológico , Testes de Sensibilidade MicrobianaRESUMO
BACKGROUND: Influenza A virus (IAV) can cause severe and life-threatening illness in humans and animals. Therefore, it is important to search for host antiviral proteins and elucidate their antiviral mechanisms for the development of potential treatments. As a part of human innate immunity, host restriction factors can inhibit the replication of viruses, among which SAM and HD domain containing deoxynucleoside triphosphate triphosphohydrolase 1 (SAMHD1) can restrict the replication of viruses, such as HIV and enterovirus EV71. Viruses also developed countermeasures in the arms race with their hosts. There are few reports about whether SAMHD1 has a restriction effect on IAV. METHODS: To investigate the impact of IAV infection on SAMHD1 expression in A549 cells, we infected A549 cells with a varying multiplicity of infection (MOI) of IAV and collected cell samples at different time points for WB and RT-qPCR analysis to detect viral protein and SAMHD1 levels. The virus replication level in the cell culture supernatant was determined using TCID50 assay. Luciferase assay was used to reveal that H5N1 virus polymerase acidic protein (PA) affected the activity of the SAMHD1 promoter. To assess the antiviral capacity of SAMHD1, we generated a knockdown and overexpressed cell line for detecting H5N1 replication. RESULTS: In this study, we observed that SAMHD1 can restrict the intracellular replication of H5N1 and that the H5N1 viral protein PA can downregulate the expression of SAMHD1 by affecting SAMHD1 transcriptional promoter activity. We also found that SAMHD1's ability to restrict H5N1 is related to phosphorylation at 592-tyrosine. CONCLUSIONS: In conclusion, we found that SAMHD1 may affect the replication of IAVs as a host restriction factor and be countered by PA. Furthermore, SAMHD1 may be a potential target for developing antiviral drugs.
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Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A , Influenza Humana , Animais , Humanos , Vírus da Influenza A/metabolismo , Fatores de Transcrição/metabolismo , Proteína 1 com Domínio SAM e Domínio HD/metabolismo , Replicação Viral , Proteínas Virais/metabolismo , Antivirais/farmacologia , Antivirais/metabolismo , Fator Regulador 3 de Interferon/metabolismoRESUMO
Stroke is a prevalent global acute cerebrovascular condition, with ischaemic stroke being the most frequently occurring type. After a stroke, neutrophils accumulate in the brain and subsequently generate and release neutrophil extracellular traps (NETs). The accumulation of NETs exacerbates the impairment of the bloodâbrain barrier (BBB), hampers neovascularization, induces notable neurological deficits, worsens the prognosis of stroke patients, and can facilitate the occurrence of t-PA-induced cerebral haemorrhage subsequent to ischaemic stroke. Alternative approaches to pharmacological thrombolysis or endovascular thrombectomy are being explored, and targeting NETs is a promising treatment that warrants further investigation.
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Armadilhas Extracelulares , Acidente Vascular Cerebral , Humanos , Armadilhas Extracelulares/metabolismo , Acidente Vascular Cerebral/terapia , Animais , Barreira Hematoencefálica/metabolismo , NeutrófilosRESUMO
BACKGROUND: Serum uric acid (UA) and the neutrophil-to-lymphocyte ratio (NLR) have been reported to be associated with outcomes in acute ischemic stroke (AIS). However, whether UA is related to the prognosis of AIS patients undergoing intravenous thrombolysis (IVT) remains inconclusive. We sought to explore the combined effect of UA and NLR on the prognosis of AIS treated with IVT. METHODS: A total of 555 AIS patients receiving IVT treatment were enrolled. Patients were categorized into four groups according to the levels of UA and NLR: LNNU (low NLR and normal UA), LNHU (low NLR and high UA), HNNU (high NLR and normal UA), and HNHU (high NLR and high UA). Multivariable logistic regression analysis was used to evaluate the value of serum UA level and NLR in predicting prognosis. The primary outcomes were major disability (modified Rankin scale (mRS) score 3-5) and death within 3 months. RESULTS: After multivariate adjustment, a high NLR (≥ 3.94) increased the risk of 3-month death or major disability (OR, 2.23; 95% CI, 1.42 to 3.55, p < 0.001). However, there was no statistically significant association between a high UA level (≥ 313.00 µmol/L) and clinical outcome. HNHU was associated with a 5.09-fold increase in the risk of death (OR, 5.09; 95% CI, 1.31-19.83; P value = 0.019) and a 1.98-fold increase in the risk of major disability (OR, 1.98; 95% CI 1.07-3.68; P value = 0.030) in comparison to LNNU. CONCLUSIONS: High serum UA levels combined with high NLR were independently associated with 3-month death and major disability in AIS patients after IVT.
Assuntos
AVC Isquêmico , Linfócitos , Neutrófilos , Terapia Trombolítica , Ácido Úrico , Humanos , Ácido Úrico/sangue , Feminino , Masculino , AVC Isquêmico/sangue , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/diagnóstico , AVC Isquêmico/mortalidade , Idoso , Pessoa de Meia-Idade , Terapia Trombolítica/métodos , Prognóstico , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Administração Intravenosa , Fibrinolíticos/administração & dosagem , Fibrinolíticos/uso terapêuticoRESUMO
Low-k SiONC thin films with excellent thermal stabilities were deposited using plasma-assisted molecular layer deposition (PA-MLD) with a tetraisocyanatesilane (Si(NCO)4) precursor, N2plasma, and phloroglucinol (C6H3(OH)3). By adjusting the order of the N2plasma exposure steps within the PA-MLD process, we successfully developed a deposition technique that allows accurate control of thickness at the Ångström level via self-limiting reactions. The thicknesses of the thin films were measured through spectroscopic ellipsometry (SE). By tuning the N2plasma power, we facilitated the formation of -NH2sites for phloroglucinol adsorption, achieving a growth per cycle of 0.18 Å cycle-1with 300 W of N2plasma power. Consequently, the thickness of the films increased linearly with each additional cycle. Moreover, the organic linkers within the film formed stable bonds through surface reactions, resulting in a negligible decrease in thickness of approximately -11% even upon exposure to a high annealing temperature of 600 °C. This observation was confirmed by SE, distinguishing the as-prepared film from previously reported low-k films that fail to maintain their thickness under similar conditions. X-ray photoelectron spectroscopy (XPS) and current-voltage (I-V) and capacitance-voltage (C-V) measurement were conducted to evaluate the composition, insulating properties, and dielectric constant according to the deposition and annealing conditions. XPS results revealed that as the plasma power increased from 200 to 300 W, the C/Si ratio increased from 0.37 to 0.67, decreasing the dielectric constant from 3.46 to 3.12. Furthermore, there was no significant difference in the composition before and after annealing, and the hysteresis decreased from 0.58 to 0.19 V owing to defect healing, while maintaining the leakage current density, breakdown field, and dielectric constant. The low dielectric constant, accurate thickness control, and excellent thermal stability of this MLD SiONC thin film enable its application as an interlayer dielectric in back-end-of-line process.
RESUMO
BACKGROUND: The mitochondrial carrier homolog 2 (MTCH2) is a mitochondrial outer membrane protein regulating mitochondrial metabolism and functions in lipid homeostasis and apoptosis. Experimental data on the interaction of MTCH2 with viral proteins in virus-infected cells are very limited. Here, the interaction of MTCH2 with PA subunit of influenza A virus RdRp and its effects on viral replication was investigated. METHODS: The human MTCH2 protein was identified as the influenza A virus PA-related cellular factor with the Y2H assay. The interaction between GST.MTCH2 and PA protein co-expressed in transfected HEK293 cells was evaluated by GST-pull down. The effect of MTCH2 on virus replication was determined by quantification of viral transcript and/or viral proteins in the cells transfected with MTCH2-encoding plasmid or MTCH2-siRNA. An interaction model of MTCH2 and PA was predicted with protein modeling/docking algorithms. RESULTS: It was observed that PA and GST.MTCH2 proteins expressed in HEK293 cells were co-precipitated by glutathione-agarose beads. The influenza A virus replication was stimulated in HeLa cells whose MTCH2 expression was suppressed with specific siRNA, whereas the increase of MTCH2 in transiently transfected HEK293 cells inhibited viral RdRp activity. The results of a Y2H assay and protein-protein docking analysis suggested that the amino terminal part of the viral PA (nPA) can bind to the cytoplasmic domain comprising amino acid residues 253 to 282 of the MTCH2. CONCLUSION: It is suggested that the host mitochondrial MTCH2 protein is probably involved in the interaction with the viral polymerase protein PA to cause negative regulatory effect on influenza A virus replication in infected cells.
Assuntos
Vírus da Influenza A , Proteínas de Transporte da Membrana Mitocondrial , Replicação Viral , Humanos , Regulação para Baixo , Células HEK293 , Células HeLa , Vírus da Influenza A/fisiologia , Vírus da Influenza A/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Ligação Proteica , RNA Polimerase Dependente de RNA/metabolismo , RNA Polimerase Dependente de RNA/genética , Proteínas Virais/metabolismo , Proteínas Virais/genética , Replicação Viral/genética , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismoRESUMO
BACKGROUND: Atrial septal defects (ASD) are the most common type of adult congenital heart disease (ACHD) associated with a high risk developing of pulmonary arterial hypertension (PAH). ASD closure is not recommended in patients with PAH and Pulmonary Vascular Resistance (PVR) ≥ 5 Wood Unit (WU). Noninvasive methods have been proposed to measure PVR; however, their accuracy remains low. Right Ventricle (RV) - Pulmonary Artery (PA) coupling is defined as the ability of the RV to adapt to high-resistance conditions. Tricuspid Annular Plane Systolic Excursion (TAPSE)/estimated pulmonary artery systolic pressure (ePASP) calculation using echocardiography is a noninvasive technique that has been proposed as a surrogate equation to evaluate RV-PA coupling. Currently, no research has demonstrated a relationship between RV-PA coupling and PVR in patients with ASD. METHODS: The study participants were consecutive eligible patients with ASD who underwent right heart catheterization (RHC) and echocardiography at Hasan Sadikin General Hospital, Bandung. Both the procedures were performed on the same day. RV-PA Coupling, defined as TAPSE/ePASP > 0.31, was assessed using echocardiography. The PVR was calculated during RHC using the indirect Fick method. RESULTS: There were 58 patients with ASD underwent RHC and echocardiography. Among them, 18 had RV/PA Coupling and 40 had RV/PA Uncoupling. The PVR values were significantly different between the two groups (p = 0.000). Correlation test between TAPSE/ePASP with PVR showed moderate negative correlation (r= -0.502, p = 0.001). TAPSE/ePASP ≤ 0.34 is the cutoff point to predict PVR > 5 WU with sensitivity of 91.7% and specificity 63.6%. CONCLUSION: This study showed a moderate negative correlation between TAPSE/ePASP and PVR. TAPSE/ePASP ≤ 0.34 could predict PVR > 5 WU with good sensitivity.