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1.
Biochem Cell Biol ; 101(4): 303-312, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36927169

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), an emerging pathogenic coronavirus, has been reported to cause excessive inflammation and dysfunction in multiple cells and organs, but the underlying mechanisms remain largely unknown. Here we showed exogenous addition of SARS-CoV-2 envelop protein (E protein) potently induced cell death in cultured cell lines, including THP-1 monocytic leukemia cells, endothelial cells, and bronchial epithelial cells, in a time- and concentration-dependent manner. SARS-CoV-2 E protein caused pyroptosis-like cell death in THP-1 and led to GSDMD cleavage. In addition, SARS-CoV-2 E protein upregulated the expression of multiple pro-inflammatory cytokines that may be attributed to activation of NF-κB, JNK and p38 signal pathways. Notably, we identified a natural compound, Ruscogenin, effectively reversed E protein-induced THP-1 death via inhibition of NLRP3 activation and GSDMD cleavage. In conclusion, these findings suggested that Ruscogenin may have beneficial effects on preventing SARS-CoV-2 E protein-induced cell death and might be a promising treatment for the complications of COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Células Endoteliais , Piroptose/fisiologia
2.
Sensors (Basel) ; 23(3)2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36772534

RESUMO

Integrated sensing and communications (ISAC) is emerging as a key technology of 6G. Owing to the low peak-to-average power ratio (PAPR) property, discrete Fourier transform spread orthogonal frequency-division multiplexing (DFT-s-OFDM) is helpful to improve the sensing range and suitable for high-frequency transmission. However, compared to orthogonal frequency-division multiplexing (OFDM), the sensing accuracy of DFT-s-OFDM is relatively poor. In this paper, frequency-domain spectral shaping (FDSS) is adopted to enhance the performances of DFT-s-OFDM including sensing accuracy and PAPR by adjusting the correlation of signals. Specifically, we first establish a signal model for the ISAC system, followed by the description of performance indicators. Then, we analyze the influence of amplitude fluctuation of frequency domain signals on sensing performance, which shows the design idea of FDSS-enhanced DFT-s-OFDM. Further, a FDSS-enhanced DFT-s-OFDM framework is introduced for ISAC, where two types of FDSS filters including a pre-equalization filter and an isotropic orthogonal transform algorithm (IOTA) filter are designed. The simulation results show that the proposed scheme can obtain about 4 dB performance gain in terms of sensing accuracy over DFT-s-OFDM. In addition, FDSS-enhanced DFT-s-OFDM can significantly reduce PAPR and improve the power amplifier efficiency.

3.
Macromol Rapid Commun ; 43(20): e2200341, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35611450

RESUMO

Synthesizing chemically recyclable solid polymeric materials is a significant strategy to potentially achieve carbon neutral production of new polymers and alleviate plastic pollution, especially when the synthesis is based on CO2 and inexpensive co-feedstocks available in large scales. Additionally, polymeric materials should have high enough molecular weight to exhibit distinguished properties from low molar mass polymers to serve for a broader range of application scenarios. However, up to now, strategies for developing solid-state CO2 -based chemically recyclable polyesters with both high molecular weight and facile property tunability are still unprecedented. Herein, a brand-new synthetic route is developed to synthesize chemically recyclable CO2 -based solid polyesters with high molecular weight (Mn up to 587.7 kg mol-1 ) and narrow dispersity (D < 1.2), which should further broaden the potential application scenarios of new CO2 -based polyesters. Additionally, complete monomer recovery from poly(δLH2 ) material is also achieved. The preserved terminal alkene groups allow facile property tuning of the polyesters via photo-initiated thiol-ene click reactions, enabling more potential utilities and further functionalizations.


Assuntos
Dióxido de Carbono , Poliésteres , Poliésteres/química , Polímeros/química , Compostos de Sulfidrila/química , Alcenos , Plásticos , Carbono
4.
J Youth Adolesc ; 51(9): 1858-1871, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35639303

RESUMO

Although psychologically controlling and autonomy-supportive parenting are important indicators of social anxiety during early adolescence, less research has explored distinct roles of father and mother parenting, especially in interdependent-oriented culture. This 3-year longitudinal study examined the reciprocal associations between such parenting and early adolescent social anxiety from multi-informants in the Chinese context. A sample of 1,140 Chinese early adolescents (51.1% boys; Mage = 10.50 years) and their parents participated at Wave 1. The results did not reveal reciprocal relations between fathers' reported parenting and social anxiety, but indicated paternal parenting effects from boys' perceptions of autonomy support to social anxiety, and child effects from social anxiety to girls' perceived psychological control. Maternal parenting effects were present for boys' perceptions of autonomy support and girls' perceptions of psychological control. The findings highlight the distinct roles of father and mother parenting across child gender and suggest differentiated relations of parenting to social anxiety during early adolescence in the Chinese context.


Assuntos
Mães , Poder Familiar , Adolescente , Ansiedade , Criança , Pai/psicologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Mães/psicologia , Poder Familiar/psicologia
5.
Angew Chem Int Ed Engl ; 58(18): 6070-6073, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-30839149

RESUMO

Aerobic organisms must rely on abundant intracellular thiols to reductively protect various vital functional units, especially ubiquitous zinc(II) thiolate sites of proteins, from deleterious oxidations resulting from oxidizing environments. Disclosed here is the first well-defined model study for reactions between zinc(II) thiolate complexes and copper(II) complexes. Among all the studied ligands of copper(II), diethyldithiocarbamate (DTC) displays a unique redox-tuning ability that enables copper(II) to resist the reduction by thiols while retaining its ability to oxidize zinc(II) thiolates to form disulfides. This work proves for the first time that it is possible to develop oxidants to discriminate between thiols and zinc(II) thiolates, alluding to a new chemical principle for how oxidants, especially universal anticancer Cu(DTC)2 , might circumvent the intracellular reductive defense around certain zinc(II) thiolate sites of proteins to kill malignant cells.


Assuntos
Cobre/química , Compostos de Sulfidrila/química , Zinco/química
6.
Eur J Pharmacol ; 946: 175666, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-36944380

RESUMO

Endotoxemia is a disease characterized by systemic inflammatory responses and organ injury caused by lipopolysaccharide (LPS) infection, with high mortality. Nicaraven (AVS), a potent hydroxyl radical scavenger, has been proven to regulate the inflammatory response in tumors. To investigate the protective effects and mechanisms of AVS in endotoxemia, mice were injected intraperitoneally with LPS to induce endotoxemia. AVS treatment significantly decreased the levels of pro-inflammatory cytokines in the serum, reduced neutrophil infiltration, attenuated multiple organ injury, and increased the survival rate in LPS-challenged mice. In the LPS-induced inflammatory model of macrophages, AVS inhibited macrophage activation, suppressed nitric oxide (NO) production, and inhibited the expression and secretion of pro-inflammatory cytokines. Mechanistically, AVS treatment up-regulated silence information regulator transcript-1 (Sirt1) expression in a time- and dose-dependent manner. AVS treatment activated the AMP-dependent protein kinase (AMPK)/Sirt1 signaling pathway and suppressed the activation of nuclear factor kappa B (NF-κB) in macrophages exposed to LPS. However, the anti-inflammatory effects of AVS could be reversed by the AMPK, the Sirt1 inhibitor, or the histone deacetylase inhibitor. We confirmed that the AMPK inhibitor inhibited AVS-mediated AMPK/Sirt1 activation and NF-κB p65 acetylation. These results suggested that AVS alleviated endotoxemia by activating the AMPK/Sirt1 signaling pathway in macrophages.


Assuntos
Endotoxemia , NF-kappa B , Animais , Camundongos , NF-kappa B/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Sirtuína 1/metabolismo , Endotoxemia/induzido quimicamente , Endotoxemia/complicações , Endotoxemia/metabolismo , Lipopolissacarídeos/metabolismo , Transdução de Sinais , Macrófagos , Inflamação/tratamento farmacológico , Inflamação/prevenção & controle , Inflamação/induzido quimicamente , Citocinas/metabolismo
7.
Innovation (Camb) ; 3(2): 100216, 2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35243470

RESUMO

Chemically recyclable solid polymeric materials with commercializable properties only using CO2 and inexpensive bulk chemicals as chemical feedstock can open a brand-new avenue to economically viable, large-scale fixation of CO2 over a long period of time. Despite previous great advancements, development of such a kind of CO2-based polymers remains a long-term unsolved research challenge of great significance. Herein, we reported the first methodology to polymerize six-membered lactone with two substituents vicinal to the ester group (HL), a compound previously found to be non-polymerizable. The present methodology enables the first synthesis of chemically recyclable solid polyesters (polyHL) with a high CO2 content (28 wt %) and large molecular weights (M n up to 613.8 kg mol-1). Transparent membranes with promising pressure-sensitive adhesive (PSA) properties comparable with their commercial counterparts can be conveniently fabricated from the polyesters. Mechanistic studies indicate that rigorous removal of water impurity is the key to the successful polymerization of the relatively inert disubstituted six-membered lactone. A complete monomer recovery from polyHL was also successfully achieved under mild catalytic conditions. The synthesis of polyHL only requires CO2 and two inexpensive bulk chemicals, H2 and 1,3-butadiene, as the starting materials, thus providing a new strategy for potential scalable chemical utilization of CO2 with desirable economic values and concomitant mitigation of CO2 emissions. This work should inspire future research to make useful new solid CO2-based polymers that can meaningfully increase the scale of chemical utilization of CO2 and promote the contribution of chemical utilization of CO2 to global mitigation of CO2 emissions.

8.
J Glob Antimicrob Resist ; 30: 1-9, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35643393

RESUMO

OBJECTIVES: This network meta-analysis aimed to compare the efficacy and safety of fluoroquinolone (FQ) monotherapy, ß-lactam (BL) monotherapy and ß-lactam/macrolide (BL-M) combination therapy in hospitalized patients with community-acquired pneumonia (CAP). METHODS: Pubmed, Embase and the Cochrane Library were searched for randomized controlled trials (RCTs) comparing FQ monotherapy, BL monotherapy and BL-M combination therapy up to July 2021. The outcomes of interest included all-cause mortality, clinical success, microbiological success and drug-related adverse events. The summary relative risks (RRs) were estimated using pairwise and Bayesian network meta-analysis. RESULTS: A total of 12 RCTs involving 5009 patients were included. In pairwise meta-analysis, no significant differences were found among FQ monotherapy, BL monotherapy and BL-M dual therapy for all-cause mortality, clinical success or microbiological success. FQ monotherapy was associated with fewer adverse events compared with BL-M therapy (RR 0.80, 95% confidence interval [CI] 0.66-0.98). The network meta-analysis showed that there was no significant difference observed among FQ monotherapy, BL monotherapy and BL-M dual therapy regarding all the outcomes. CONCLUSION: FQ monotherapy, BL monotherapy and BL-M combination therapy demonstrated similar efficacy and safety for hospitalized patients with CAP in this network meta-analysis. Due to the limitations of quality and quantity of the included studies, it is difficult to make a definitive recommendation before more large-scale and high-quality RCTs are conducted.


Assuntos
Infecções Comunitárias Adquiridas , Pneumonia , Antibacterianos/efeitos adversos , Infecções Comunitárias Adquiridas/microbiologia , Quimioterapia Combinada , Fluoroquinolonas/efeitos adversos , Humanos , Metanálise em Rede , Pneumonia/tratamento farmacológico , Pneumonia/microbiologia , beta-Lactamas/efeitos adversos
9.
Biophys Chem ; 276: 106610, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34089978

RESUMO

In the new millennium, the outbreak of new coronavirus has happened three times: SARS-CoV, MERS-CoV, and SARS-CoV-2. Unfortunately, we still have no pharmaceutical weapons against the diseases caused by these viruses. The pandemic of SARS-CoV-2 reminds us the urgency to search new drugs with totally different mechanism that may target the weaknesses specific to coronaviruses. Herein, we disclose a computational evaluation of targeted oxidation strategy (TOS) for potential inhibition of SARS-CoV-2 by disulfiram, a 70-year-old anti-alcoholism drug, and predict a multiple-target mechanism. A preliminary list of promising TOS drug candidates targeting the two thiol proteases of SARS-CoV-2 are proposed upon virtual screening of 32,143 disulfides.


Assuntos
Dissuasores de Álcool/química , Antivirais/química , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases Semelhantes à Papaína de Coronavírus/antagonistas & inibidores , Dissulfiram/química , Inibidores de Proteases/química , SARS-CoV-2/química , Dissuasores de Álcool/farmacologia , Antivirais/farmacologia , Domínio Catalítico , Proteases 3C de Coronavírus/química , Proteases 3C de Coronavírus/genética , Proteases 3C de Coronavírus/metabolismo , Proteases Semelhantes à Papaína de Coronavírus/química , Proteases Semelhantes à Papaína de Coronavírus/genética , Proteases Semelhantes à Papaína de Coronavírus/metabolismo , Dissulfiram/farmacologia , Reposicionamento de Medicamentos , Expressão Gênica , Humanos , Cinética , Simulação de Acoplamento Molecular , Oxirredução , Inibidores de Proteases/farmacologia , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Teoria Quântica , SARS-CoV-2/enzimologia , Especificidade por Substrato , Termodinâmica , Tratamento Farmacológico da COVID-19
10.
Genome Announc ; 3(1)2015 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-25700405

RESUMO

Rhodobacteraceae strain PD-2 was isolated from the marine microalga Prorocentrum donghaiense. It has algicidal activity toward its host and could produce N-acylhomoserine lactone signals. Here, we present the draft genome of strain PD-2, which contains 5,227,214 bp with an average GC content of 66.19%. There were 4,864 encoding gene sequences and two clusters of luxI and luxR homologues identified.

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