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1.
Discov Oncol ; 15(1): 591, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39453509

RESUMEN

Hepatocellular carcinoma (HCC) is associated with high mortality rate. This study investigated the status of lipid metabolism-related genes in HCC. Bulk transcriptomic and single-cell sequencing data for HCC were retrieved from public databases. The single-cell sequencing data was subjected to dimensionality reduction, which facilitated the annotation of distinct cell subpopulations and marker gene expression analysis within each subpopulation. Genes associated with lipid metabolism in liver cells were identified, and a machine-learning model was developed using the bulk transcriptomic data randomly partitioned into training and validation sets. The efficacy of the model was validated using these two sets. A multifactorial Cox analysis on the model genes combined with clinical features, led to the identification of age, HMGCS2, HNRNPU, and RAN as independent prognostic factors, which were included in the nomogram model construction and validation. A weighted gene co-expression analysis of all genes of the bulk transcriptome samples revealed the correlation between gene modules and risk score. Genes with cor > 0.4 in the highest-expressing module were selected for Gene Ontology and Kyoto Encyclopedia of Genes and Genomes functional enrichment analysis. Immune-related analysis was conducted based on seven algorithms for immune cell infiltration prediction. For the genes in the nomogram model, the expression in clinical pathological factors was also analyzed. The drug sensitivity analysis offered a reference for the selection of targeting drugs. This investigation provides novel insights and a theoretical basis for the prognosis, treatment, and pharmaceutical advancements for patients diagnosed with HCC.

2.
Heliyon ; 10(18): e37361, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39309925

RESUMEN

Background: The role and molecular mechanisms of collagen type VII (COL7A1) in cholangiocarcinoma (CCA) remain unknown. Methods: We analyzed the expression of COL7A1 in CCA and its relationship with patient prognosis using bioinformatic techniques. Expression levels of COL7A1 in CCA cells and tissues were detected using reverse transcription-quantitative PCR, western blotting, and immunohistochemistry. The effects of COL7A1 expression on the proliferation, migration, and invasion of CCA cells were assessed using CCK-8, colony formation, and Transwell assays. Bioinformatics and luciferase reporter gene assays were performed to examine the binding of KLF4 to COL7A1, and cytological experiments further verified the role of KLF4 in regulating the CCA phenotype through COL7A1. Xenograft mouse models were established to investigate the effects of COL7A1 on CCA tumor growth in vivo. Results: CCA tissues exhibited higher COL7A1 expression than normal bile duct tissues. There was no significant correlation between high or low COL7A1 expression and the survival time of patients with CCA. COL7A1 knockdown inhibited CCA cell proliferation, migration, and invasion. Furthermore, COL7A1 knockdown suppressed the activation of the PI3K/AKT signaling pathway. KLF4 can bind to COL7A1 and regulate COL7A1 expression, which in turn regulates the PI3K/AKT signaling pathway and impacts the proliferation and metastasis of CCA cells. Conclusion: Our findings suggest that KLF4 regulates CCA cell proliferation, migration, and invasion via the COL7A1/PI3K/AKT axis.

3.
Transl Vis Sci Technol ; 13(7): 20, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39078643

RESUMEN

Purpose: To examine the effects of serum growth hormone (GH) and insulin-like growth factor-1 (IGF-1) on choroidal structures with different blood glucose levels in patients with diabetes mellitus (DM) with acromegaly without diabetic retinopathy. Methods: Eighty-eight eyes of 44 patients with acromegaly were divided into a nondiabetic group (23 patients, 46 eyes) and a diabetic group (21 patients, 42 eyes). Forty-four age- and sex-matched healthy controls and 21 patients with type 2 DM without diabetic retinopathy were also included. Linear regression models with a simple slope analysis were used to identify the correlation and interaction between endocrine parameters and choroidal thickness (ChT), total choroidal area (TCA), luminal area (LA), stromal area (SA), and choroidal vascular index (CVI). Results: Our study revealed significant increases in the ChT, LA, SA, and TCA in patients with acromegaly compared with healthy controls, with no difference in the CVI. Comparatively, patients with DM with acromegaly had greater ChT than matched patients with type 2 DM, with no significant differences in other choroidal parameters. The enhancement of SA, LA and TCA caused by an acromegalic status disappeared in patients with diabetic status, whereas ChT and CVI were not affected by the interaction. In the diabetic acromegaly, higher IGF-1 (P = 0.006) and GH levels (P = 0.049), longer DM duration (P = 0.007), lower blood glucose (P = 0.001), and the interaction between GH and blood glucose were associated independently with thicker ChT. Higher GH levels (P = 0.016, 0.004 and 0.007), longer DM duration (P = 0.022, 0.013 and 0.013), lower blood glucose (P = 0.034, 0.011 and 0.01), and the interaction of IGF-1 and blood glucose were associated independently with larger SA, LA, and TCA. As blood glucose levels increased, the positive correlation between serum GH level and ChT diminished, and became insignificant when blood glucose was more than 7.35 mM/L. The associations between serum IGF-1 levels and LA, SA, and TCA became increasingly negative, with LA, becoming significantly and negatively associated to the GH levels only when blood glucose levels were more than 8.59 mM/L. Conclusions: Acromegaly-related choroidal enhancements diminish in the presence of DM. In diabetic acromegaly, blood glucose levels are linked negatively with changes in choroidal metrics and their association with GH and IGF-1. Translational Relevance: We revealed the potential beneficial impacts of IGF-1 and GH on structural measures of the choroid in patients with DM at relatively well-controlled blood glucose level, which could provide a potential treatment target for diabetic retinopathy.


Asunto(s)
Acromegalia , Glucemia , Coroides , Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Factor I del Crecimiento Similar a la Insulina , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/análisis , Acromegalia/sangre , Acromegalia/complicaciones , Femenino , Masculino , Persona de Mediana Edad , Coroides/patología , Glucemia/análisis , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Retinopatía Diabética/sangre , Adulto , Anciano , Tomografía de Coherencia Óptica , Hormona de Crecimiento Humana/sangre , Estudios de Casos y Controles
4.
Breast ; 76: 103762, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38924994

RESUMEN

BACKGROUND: Male breast cancer (MBC) is a rare disease. Although several large-scale studies have investigated MBC patients in other countries, the features of MBC patients in China have not been fully explored. This study aims to explore the features of Chinese MBC patients comprehensively. METHODS: We retrospectively collected data of MBC patients from 36 centers in China. Overall survival (OS) was evaluated by the Kaplan-Meier method, log-rank test, and Cox regression analyses. Multivariate Cox analyses were used to identify independent prognostic factors of the patients. RESULTS: In total, 1119 patients were included. The mean age at diagnosis was 60.9 years, and a significant extension over time was observed (P < 0.001). The majority of the patients (89.1 %) received mastectomy. Sentinel lymph node biopsy was performed in 7.8 % of the patients diagnosed in 2009 or earlier, and this percentage increased significantly to 38.8 % in 2020 or later (P < 0.001). The five-year OS rate for the population was 85.5 % [95 % confidence interval (CI), 82.8 %-88.4 %]. Multivariate Cox analysis identified taxane-based [T-based, hazard ratio (HR) = 0.32, 95 % CI, 0.13 to 0.78, P = 0.012] and anthracycline plus taxane-based (A + T-based, HR = 0.47, 95 % CI, 0.23 to 0.96, P = 0.037) regimens as independent protective factors for OS. However, the anthracycline-based regimen showed no significance in outcome (P = 0.175). CONCLUSION: As the most extensive MBC study in China, we described the characteristics, treatment and prognosis of Chinese MBC population comprehensively. T-based and A + T-based regimens were protective factors for OS in these patients. More research is required for this population.


Asunto(s)
Neoplasias de la Mama Masculina , Mastectomía , Biopsia del Ganglio Linfático Centinela , Humanos , Neoplasias de la Mama Masculina/patología , Neoplasias de la Mama Masculina/mortalidad , Neoplasias de la Mama Masculina/terapia , Neoplasias de la Mama Masculina/epidemiología , Masculino , Persona de Mediana Edad , China/epidemiología , Estudios Retrospectivos , Mastectomía/estadística & datos numéricos , Anciano , Biopsia del Ganglio Linfático Centinela/estadística & datos numéricos , Adulto , Pronóstico , Modelos de Riesgos Proporcionales , Estimación de Kaplan-Meier , Taxoides/uso terapéutico , Tasa de Supervivencia , Hidrocarburos Aromáticos con Puentes/uso terapéutico , Antraciclinas/uso terapéutico , Anciano de 80 o más Años
5.
Nat Commun ; 15(1): 2478, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509092

RESUMEN

Biological cell membrane featuring smart mass-transport channels and sub-10 nm thickness was viewed as the benchmark inspiring the design of separation membranes; however, constructing highly connective and adaptive pore channels over large-area membranes less than 10 nm in thickness is still a huge challenge. Here, we report the design and fabrication of sub-8 nm networked cage nanofilms that comprise of tunable, responsive organic cage-based water channels via a free-interface-confined self-assembly and crosslinking strategy. These cage-bearing composite membranes display outstanding water permeability at the 10-5 cm2 s-1 scale, which is 1-2 orders of magnitude higher than that of traditional polymeric membranes. Furthermore, the channel microenvironments including hydrophilicity and steric hindrance can be manipulated by a simple anion exchange strategy. In particular, through ionically associating light-responsive anions to cage windows, such 'smart' membrane can even perform graded molecular sieving. The emergence of these networked cage-nanofilms provides an avenue for developing bio-inspired ultrathin membranes toward smart separation.

6.
J Virol ; 98(3): e0181523, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38421179

RESUMEN

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne bunyavirus with high pathogenicity. There has been a gradual increase in the number of reported cases in recent years, with high morbidity and mortality rates. The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway plays an important role in the innate immune defense activated by viral infection; however, the role of the cGAS-STING signaling pathway during SFTSV infection is still unclear. In this study, we investigated the relationship between SFTSV infection and cGAS-STING signaling. We found that SFTSV infection caused the release of mitochondrial DNA into the cytoplasm and inhibits downstream innate immune signaling pathways by activating the cytoplasmic DNA receptor cGAS. We found that the SFTSV envelope glycoprotein Gn was a potent inhibitor of the cGAS-STING pathway and blocked the nuclear accumulation of interferon regulatory factor 3 and p65 to inhibit downstream innate immune signaling. Gn of SFTSV interacted with STING to inhibit STING dimerization and inhibited K27-ubiquitin modification of STING to disrupt the assembly of the STING-TANK-binding kinase 1 complex and downstream signaling. In addition, Gn was found to be involved in inducing STING degradation, further inhibiting the downstream immune response. In conclusion, this study identified the important role of the glycoprotein Gn in the antiviral innate immune response and revealed a novel mechanism of immune escape for SFTSV. Moreover, this study increases the understanding of the pathogenic mechanism of SFTSV and provides new insights for further treatment of SFTS. IMPORTANCE: Severe fever with thrombocytopenia syndrome virus (SFTSV) is a newly discovered virus associated with severe hemorrhagic fever in humans. However, the role of the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway during SFTSV infection is still unclear. We found that SFTSV infection inhibits downstream innate immune signaling pathways by activating the cytoplasmic DNA receptor cGAS. In addition, SFTSV Gn blocked the nuclear accumulation of interferon regulatory factor 3 and p65 to inhibit downstream innate immune signaling. Moreover, we determined that Gn of SFTSV inhibited K27-ubiquitin modification of STING to disrupt the assembly of the STING-TANK-binding kinase 1 complex and downstream signaling. We found that the SFTSV envelope glycoprotein Gn is a potent inhibitor of the cGAS-STING pathway. In conclusion, this study highlights the crucial function of the glycoprotein Gn in the antiviral innate immune response and reveals a new method of immune escape of SFTSV.


Asunto(s)
FN-kappa B , Síndrome de Trombocitopenia Febril Grave , Humanos , FN-kappa B/metabolismo , Factor 3 Regulador del Interferón/metabolismo , Transducción de Señal/genética , Inmunidad Innata/genética , Nucleotidiltransferasas/metabolismo , Interferones/metabolismo , Antivirales , Ubiquitinas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo
7.
Mult Scler Relat Disord ; 84: 105423, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38359691

RESUMEN

PURPOSE: To assess the retinal structural and microvascular change in aquaporin-4 antibody (AQP4) positive neuromyelitis optica spectrum disorder (NMOSD) patients and the correlation with clinical features. METHODS: A cross-sectional study was performed with optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) to measure retinal structure and microvascular parameters in AQP4 positive NMOSD patients. RESULTS: Sixty-two NMOSD patients (44 eyes with ON, NMOSD+ON; 77 eyes without ON, NMOSD-ON) and 62 healthy controls (HC, 124 eyes) were included. BCVA was worse in NMOSD patients compared to HC (p<0.001). Peripapillary retinal nerve fiber layer (pRNFL, p<0.001) and ganglion cell complex (GCC, p<0.001) was thinner in NMOSD+ON eyes compared to NMOSD-ON eyes and HC. Compared to HC, pRNFL (p = 0.002) and GCC (p = 0.001) was thinner in NMOSD-ON eyes. The vessel density (VD) in superficial capillary plexus (SCP, NMOSD+ON vs HC p<0.001, NMOSD-ON vs HC p = 0.002) and radial peripapillary capillary (RPC, NMOSD+ON vs HC p<0.001, NMOSD-ON vs HC p = 0.001) were also lower in NMOSD patients than HC independent of the history of ON. ON frequency and BCVA were correlated with the thickness of pRNFL and GCC, and VD in SCP and RPC (all p<0.001). EDSS was correlated with thickness of GCC (p = 0.008), and VD in SCP (p = 0.013), DCP (p<0.001) and RPC (p = 0.009). CONCLUSIONS: Subclinical degradation of retinal structure and microvasculature was found in NMOSD patients before the occurrence of ON, and was correlated with clinical disability. Retinal parameter might be a tool to estimate the disease progression and investigate the pathogenesis of NMOSD.


Asunto(s)
Acuaporinas , Neuromielitis Óptica , Neuritis Óptica , Humanos , Neuromielitis Óptica/complicaciones , Neuromielitis Óptica/diagnóstico por imagen , Tomografía de Coherencia Óptica , Estudios Transversales , Angiografía/efectos adversos , Autoanticuerpos/metabolismo , Acuaporina 4
8.
Macromol Rapid Commun ; 45(8): e2300676, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38232334

RESUMEN

Poly(ionic liquid) (PIL)-based porous membranes are extensively investigated as soft polymer actuators. While PILs have shown significant advancements in membrane fabrication and stabilization of metal nanoparticles (MNPs), research on integrating MNPs into porous membranes to achieve actuation behavior under multiple stimuli is limited. Herein, this work presents a new paradigm for designing a porous PIL-polyacrylic acid (PAA) membrane with a distinct MNP gradient via a top-bottom diffusion approach involving a metal salt precursor solution and NaBH4 as a reducing agent. The strong binding sites provided by PILs, combined with the gradient distribution of -COO- groups across the membrane cross-section, play a significant role in controlling the MNPs' gradient distribution. Interestingly, the MNPs within the membrane display excellent catalytic activity in exothermic reactions such as H2O2 decomposition, dissipating uneven heat that quickly permeates the membrane network. This induces asymmetrical swelling of polymer chains, resulting in rapid membrane bending. Furthermore, such MNP-loaded membrane could serve as a portable test paper for visually monitoring H2O2. This advancement paves the way for the development of intricate smart actuation materials and expands their practical applications in various real-life scenarios.


Asunto(s)
Líquidos Iónicos , Nanopartículas del Metal , Líquidos Iónicos/química , Nanopartículas del Metal/química , Porosidad , Polímeros/química , Resinas Acrílicas/química , Membranas Artificiales , Peróxido de Hidrógeno/química , Catálisis , Propiedades de Superficie , Tamaño de la Partícula
9.
Small Methods ; 8(9): e2301468, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38295090

RESUMEN

The exploration of a facile approach to create structurally versatile substances carrying air-stable radicals is highly desired, but still a huge challenge in chemistry and materials science. Herein, a non-contact method to generate air-stable radicals by exposing pyridine/imidazole ring-bearing substances to volatile cyanuric chloride vapor, harnessed as a chemical fuel is reported. This remarkable feat is accomplished through a nucleophilic substitution reaction, wherein an intrinsic electron transfer event transpires spontaneously, originating from the chloride anion (Cl-) to the cationic nitrogen (N+) atom, ultimately giving rise to pyridinium/imidazolium radicals. Impressively, the generated radicals exhibit noteworthy stability in the air over one month owing to the delocalization of the unpaired electron through the extended and highly fused π-conjugated pyridinium/imidazolium-triazine unit. Such an approach is universal to diverse substances, including organic molecules, metal-organic complexes, hydrogels, polymers, and organic cage materials. Capitalizing on this versatile technique, surface radical functionalization can be readily achieved across diverse substrates. Moreover, the generated radical species showcase a myriad of high-performance applications, including mimicking natural peroxidase to accelerate oxidation reactions and achieving high-efficiency near-infrared photothermal conversion and photothermal bacterial inhibition.

10.
Anal Bioanal Chem ; 416(5): 1179-1188, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38148365

RESUMEN

A facile and sensitive fluorescent and colorimetric dual-readout assay for detection of acid phosphatase (ACP) was developed via Ce(III) ions-directed aggregation-induced emission (AIE) of glutathione-protected gold nanoclusters (GSH-AuNCs) and oxidase-mimicking activity of Ce(IV) ions. Free Ce(IV) ions exhibited a strong oxidase-mimetic activity, catalytically oxidizing colorless 3,3',5,5'-tetramethylbenzidine (TMB) into its blue product oxTMB in the presence of dissolved O2, thus triggering a remarkable color reaction detected visually. ACP can hydrolyze L-ascorbic acid-2-phosphate (AAP) with the production of ascorbic acid (AA). The AA is able to reduce Ce(IV) ions to Ce(III) ions, thus quenching the oxidase-mimetic activity of Ce(IV) ions. Meanwhile, Ce(III) ions induce AIE of GSH-AuNCs, resulting in the enhancement of the fluorescence signal of GSH-AuNCs. Both the fluorescent and colorimetric dual-mode analysis platforms exhibit a sensitive response to ACP, providing detection limits as low as 0.101 U/L and 0.200 U/L, respectively. Besides, this fabricated dual-mode detection platform holds the potential for analysis of ACP in human serum samples and screening inhibitors for ACP. With good performance and practicability, this study shows promising application in the convenient and reliable determination of ACP activity.


Asunto(s)
Fosfatasa Ácida , Cerio , Humanos , Oxidorreductasas , Colorimetría/métodos , Iones , Límite de Detección
11.
Front Med (Lausanne) ; 10: 1232814, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37502362

RESUMEN

Background: Hepatocellular carcinoma (HCC) represents a complex ailment characterized by an unfavorable prognosis in advanced stages. The involvement of immune cells in HCC progression is of significant importance. Moreover, metastasis poses a substantial impediment to enhanced prognostication for HCC patients, with anoikis playing an indispensable role in facilitating the distant metastasis of tumor cells. Nevertheless, limited investigations have been conducted regarding the utilization of anoikis factors for predicting HCC prognosis and assessing immune infiltration. This present study aims to identify hepatocellular carcinoma-associated anoikis-related genes (ANRGs), establish a robust prognostic model for HCC, and delineate distinct immune characteristics based on the anoikis signature. Cell migration and cytotoxicity experiments were performed to validate the accuracy of the ANRGs model. Methods: Consensus clustering based on ANRGs was employed in this investigation to categorize HCC samples obtained from both TCGA and Gene Expression Omnibus (GEO) cohorts. To assess the differentially expressed genes, Cox regression analysis was conducted, and subsequently, prognostic gene signatures were constructed using LASSO-Cox methodology. External validation was performed at the International Cancer Genome Conference. The tumor microenvironment (TME) was characterized utilizing ESTIMATE and CIBERSORT algorithms, while machine learning techniques facilitated the identification of potential target drugs. The wound healing assay and CCK-8 assay were employed to evaluate the migratory capacity and drug sensitivity of HCC cell lines, respectively. Results: Utilizing the TCGA-LIHC dataset, we devised a nomogram integrating a ten-gene signature with diverse clinicopathological features. Furthermore, the discriminative potential and clinical utility of the ten-gene signature and nomogram were substantiated through ROC analysis and DCA. Subsequently, we devised a prognostic framework leveraging gene expression data from distinct risk cohorts to predict the drug responsiveness of HCC subtypes. Conclusion: In this study, we have established a promising HCC prognostic ANRGs model, which can serve as a valuable tool for clinicians in selecting targeted therapeutic drugs, thereby improving overall patient survival rates. Additionally, this model has also revealed a strong connection between anoikis and immune cells, providing a potential avenue for elucidating the mechanisms underlying immune cell infiltration regulated by anoikis.

12.
Microbiol Spectr ; 11(3): e0413822, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37125923

RESUMEN

Enterovirus D68 (EV-D68) is a globally emerging pathogen causing severe respiratory illnesses mainly in children. The protease from EV-D68 could impair type I interferon (IFN-I) production. However, the role of the EV-D68 structural protein in antagonizing host antiviral responses remains largely unknown. We showed that the EV-D68 structural protein VP3 interacted with IFN regulatory factor 7 (IRF7), and this interaction suppressed the phosphorylation and nuclear translocation of IRF7 and then repressed the transcription of IFN. Furthermore, VP3 inhibited the TNF receptor associated factor 6 (TRAF6)-induced ubiquitination of IRF7 by competitive interaction with IRF7. IRF7Δ305-503 showed much weaker interaction ability to VP3, and VP3Δ41-50 performed weaker interaction ability with IRF7. The VP3 from enterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16) was also found to interact with the IRF7 protein. These results indicate that the enterovirus structural protein VP3 plays a pivotal role in subverting host innate immune responses and may be a potential target for antiviral drug research. IMPORTANCE EV-D68 is a globally emerging pathogen that causes severe respiratory illnesses. Here, we report that EV-D68 inhibits innate immune responses by targeting IRF7. Further investigations revealed that the structural protein VP3 inhibited the TRAF6-induced ubiquitination of IRF7 by competitive interaction with IRF7. These results indicate that the control of IRF7 by VP3 may be a mechanism by which EV-D68 represses IFN-I production.


Asunto(s)
Enterovirus Humano D , Infecciones por Enterovirus , Enterovirus , Interferón Tipo I , Niño , Humanos , Enterovirus Humano D/fisiología , Factor 7 Regulador del Interferón/metabolismo , Factor 6 Asociado a Receptor de TNF/metabolismo , Antivirales/farmacología , Antígenos Virales/metabolismo
13.
Org Lett ; 25(19): 3391-3396, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37162168

RESUMEN

In this work, we disclose two sets of highly diastereo- and enantioselective [3 + 2] cycloadditions of iminoesters with various α-substituted acrylates, especially for sterically hindered and weakly activated α-aryl or alkyl-substituted acrylates and alkenal, alkynal, or unstable aliphatic aldehyde-derived iminoesters, catalyzed by the AgHMDS/DTBM-Segphos or Ag2O/CA-AA-Amidphos catalytic system, achieving the stereodivergent synthesis of chiral C4-ester-quaternary exo- or endo-pyrrolidines with high yields and excellent diastereo- and enantioselectivities (up to >99:1 dr and >99% ee). More importantly, the gram-scale synthetic exo-adduct displays significant applications in the aspect of realizing the total synthesis of the spirotryprostatin A alkaloid via nine steps in a 36% overall yield.

15.
J Virol ; 97(4): e0030223, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-37039677

RESUMEN

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a newly identified phlebovirus associated with severe hemorrhagic fever in humans. Studies have shown that SFTSV nucleoprotein (N) induces BECN1-dependent autophagy to promote viral assembly and release. However, the function of other SFTSV proteins in regulating autophagy has not been reported. In this study, we identify SFTSV NSs, a nonstructural protein that forms viroplasm-like structures in the cytoplasm of infected cells as the virus component mediating SFTSV-induced autophagy. We found that SFTSV NSs-induced autophagy was inclusion body independent, and most phenuivirus NSs had autophagy-inducing effects. Unlike N protein-induced autophagy, SFTSV NSs was key in regulating autophagy by interacting with the host's vimentin in an inclusion body-independent manner. NSs interacted with vimentin and induced vimentin degradation through the K48-linked ubiquitin-proteasome pathway. This negatively regulating Beclin1-vimentin complex formed and promoted autophagy. Furthermore, we identified the NSs-binding domain of vimentin and found that overexpression of wild-type vimentin antagonized the induced effect of NSs on autophagy and inhibited viral replication, suggesting that vimentin is a potential antiviral target. The present study shows a novel mechanism through which SFTSV nonstructural protein activates autophagy, which provides new insights into the role of NSs in SFTSV infection and pathogenesis. IMPORTANCE Severe fever with thrombocytopenia syndrome virus (SFTSV) is a newly emerging tick-borne pathogen that causes multifunctional organ failure and even death in humans. As a housekeeping mechanism for cells to maintain steady state, autophagy plays a dual role in viral infection and the host's immune response. However, the relationship between SFTSV infection and autophagy has not been described in detail yet. Here, we demonstrated that SFTSV infection induced complete autophagic flux and facilitated viral proliferation. We also identified a key mechanism underlying NSs-induced autophagy, in which NSs interacted with vimentin to inhibit the formation of the Beclin1-vimentin complex and induced vimentin degradation through K48-linked ubiquitination modification. These findings may help us understand the new functions and mechanisms of NSs and may aid in the identification of new antiviral targets.


Asunto(s)
Autofagia , Phlebovirus , Síndrome de Trombocitopenia Febril Grave , Vimentina , Proteínas no Estructurales Virales , Humanos , Autofagia/genética , Beclina-1/metabolismo , Phlebovirus/metabolismo , Síndrome de Trombocitopenia Febril Grave/fisiopatología , Síndrome de Trombocitopenia Febril Grave/virología , Vimentina/genética , Vimentina/metabolismo , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo , Replicación Viral/fisiología , Regulación hacia Abajo , Dominios Proteicos
16.
Acc Chem Res ; 55(24): 3675-3687, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36469417

RESUMEN

ConspectusDiscovering and constructing molecular functionality platforms for materials chemistry innovation has been a persistent target in the fields of chemistry, materials, and engineering. Around this task, basic scientific questions can be asked, novel functional materials can be synthesized, and efficient system functionality can be established. Poly(ionic liquid)s (PILs) have attracted growing interest far beyond polymer science and are now considered an interdisciplinary crossing point between multiple research areas due to their designable chemical structure, intriguing physicochemical properties, and broad and diverse applications. Recently, we discovered that 1,2,4-triazolium-type PILs show enhanced performance profiles, which are due to stronger and more abundant supramolecular interactions ranging from hydrogen bonding to metal coordination, when compared with structurally similar imidazolium counterparts. This phenomenon in our view can be related to the smart hydrogen atoms (SHAs), that is, any proton that binds to the carbon in the N-heterocyclic cations of 1,2,4-triazolium-type PILs. The replacement of one carbon by an electron-withdrawing nitrogen atom in the broadly studied heterocyclic imidazolium ring will further polarize the C-H bond (especially for C5-H) of the resultant 1,2,4-triazolium cation and establish new chemical tools for materials design. For instance, the H-bond-donating strength of the SHA, as well as its BroÌ·nsted acidity, is increased. Furthermore, polycarbene complexes can be readily formed even in the presence of weak or medium bases, which is by contrast rather challenging for imidazolium-type PILs. The combination of SHAs with the intrinsic features of heterocyclic cation-functionalized PILs (e.g., N-coordination capability and polymeric multibinding effects) enables new phenomena and therefore innovative materials applications.In this Account, recent progress on SHAs is presented. SHA-related applications in several research branches are highlighted together with the corresponding materials design at size scales ranging from nano- to micro- and macroscopic levels. At a nanoscopic level, it is possible to manipulate the interior and outer shapes and surface properties of PIL nanocolloids by adjusting the hydrogen bonds (H-bonds) between SHAs and water. Owing to the interplay of polycarbene structure, N-coordination, and the polymer multidentate binding of 1,2,4-triazolium-type PILs, metal clusters with controllable size at sub-nanometer scale were successfully synthesized and stabilized, which exhibited record-high catalytic performance in H2 generation via methanolysis of ammonia borane. At the microscopic level, SHAs are found to efficiently catalyze single crystal formation of structurally complex organics. Free protons in situ released from the SHAs serve as organocatalysts to activate formation of C-N bonds at room temperature in a series of imine-linked crystalline porous organics, such as organic cages, macrocycles and covalent organic frameworks; meanwhile the concurrent "salting-out" effect of PILs as polymers in solution accelerated the crystallization rate of product molecules by at least 1 order of magnitude. At the macroscopic scale, by finely regulating the supramolecular interactions of SHAs, a series of functional supramolecular porous polyelectrolyte membranes (SPPMs) with switchable pores and gradient cross-sectional structures were manufactured. These membranes demonstrate impressive figures of merit, ranging from chiral separation and proton recognition to switchable optical properties and real-time chemical reaction monitoring. Although the concept of SHAs is in the incipient stage of development, our successful examples of applications portend bright prospects for materials chemistry innovation.

17.
Am J Reprod Immunol ; 88(4): e13610, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35957616

RESUMEN

PROBLEM: Hepatitis B virus (HBV) infection is more likely to develop a state of chronicity in early life, particularly mother-to-child transmission (MTCT) of HBV in the fetus during pregnancy. Till now, little is known about the impact of chronic HBV infection on the immune status of the maternal-fetus interface, and the immune profile of placental lymphocytes in MTCT of HBV is poorly understood. METHOD OF STUDY: Thirteen term pregnant women with chronic HBV infection (HBV-PW) and thirteen normal pregnant women as healthy control (HC-PW) were enrolled. The profile of placental immune cells and paired peripheral blood were analyzed by flow cytometry and immunohistochemistry. RESULTS: Compared with HC-PW, the frequency of CD8+ T cells from the term placenta of HBV-PW was significantly reduced. These cells showed decreased expression of activation molecules CD69 and HLA-DR; thus, decidual CD8+ T cells from HBV-PW demonstrated hypofunctional signature as evidenced by significantly reduced production of IFN-γ, as well as compromised ability of degranulation and proliferation. CONCLUSIONS: These findings supported that hypoactivated decidual CD8+ T cells might possess compromised ability in chronically HBV-infected term pregnant women. Our study provides robust evidence for the necessity and importance of antiviral intervention in HBV-PW to prevent MTCT of HBV.


Asunto(s)
Hepatitis B Crónica , Hepatitis B , Antivirales/metabolismo , Antivirales/uso terapéutico , Linfocitos T CD8-positivos , Decidua , Femenino , Virus de la Hepatitis B/fisiología , Humanos , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Placenta , Embarazo
18.
Cancer Cell Int ; 22(1): 264, 2022 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-35996149

RESUMEN

Interaction between tumor cells and tumor microenvironment (TME) is critical to promote tumor progression and metastasis. As the most abundant immune cells in TME, macrophages can be polarized into M2-like tumor-associated macrophages (TAMs) which further promote tumor progression. However, to date, the molecular mechanisms of TAM polarization in TME are still largely unknown. In the present study, we revealed that circular RNA circWWC3 could up-regulate the expression and secretion of IL-4 in breast cancer cells. Enhanced secretion of IL-4 from breast cancer cells could augment the M2-like polarization of macrophages in TME, which further promotes the migration of breast cancer cells. In addition, increased secretion of IL-4 from breast cancer cells could induce the expression PD-L1 in M2 macrophages. Moreover, up-regulated IL-4 also enhanced the expression of PD-L1 in breast cancer cells, which further facilitates breast cancer immune evasion. Though analyzing the expression of circWWC3, IL-4, PD-L1, and CD163 in 140 cases of breast cancer tissues, we found that high expression of circWWC3 was associated with poor overall survival and disease-free survival of breast cancer patients. Breast cancer patients with circWWC3high/PD-L1high breast cancer cells and CD163high macrophages had a poorer overall survival and disease-free survival. Conclusively, circWWC3 might augment breast cancer progression through promoting M2 macrophage polarization and tumor immune escape via regulating the expression and secretion of IL-4. CircWWC3 might be a potential therapeutic target in breast cancer.

19.
J Virol ; 96(14): e0078822, 2022 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-35862701

RESUMEN

Dabie bandavirus (DBV) is an emerging Bandavirus that causes multiorgan failure with a high fatality rate in humans. While many viruses can manipulate the actin cytoskeleton to facilitate viral growth, the regulation pattern of the actin cytoskeleton and the molecular mechanisms involved in DBV entry into the host cells remain unclear. In this study, we demonstrate that expression of nonstructural protein (NSs) or infection with DBV induces actin rearrangement, which presents a point-like distribution, and this destruction is dependent on inclusion bodies (IBs). Further experiments showed that NSs inhibits viral adsorption by destroying the filopodium structure. In addition, NSs also compromised the viral entry by inhibiting clathrin aggregation on the cell surface and capturing clathrin into IBs. Furthermore, NSs induced clathrin light chain B (CLTB) degradation through the K48-linked ubiquitin proteasome pathway, which could negatively regulate clathrin-mediated endocytosis, inhibiting the viral entry. Finally, we confirmed that this NSs-induced antiviral mechanism is broadly applicable to other viruses, such as enterovirus 71 (EV71) and influenza virus, A/PR8/34 (PR8), which use the same clathrin-mediated endocytosis to enter host cells. In conclusion, our study provides new insights into the role of NSs in inhibiting endocytosis and a novel strategy for treating DBV infections. IMPORTANCEDabie bandavirus (DBV), a member of the Phenuiviridae family, is a newly emerging tick-borne pathogen that causes multifunctional organ failure and even death in humans. The actin cytoskeleton is involved in various crucial cellular processes and plays an important role in viral life activities. However, the relationship between DBV infection and the actin cytoskeleton has not been described in detail. Here, we show for the first time the interaction between NSs and actin to induce actin rearrangement, which inhibits the viral adsorption and entry. We also identify a key mechanism underlying NSs-induced entry inhibition in which NSs prevents clathrin aggregation on the cell surface by hijacking clathrin into the inclusion body and induces CLTB degradation through the K48-linked ubiquitination modification. This paper is the first to reveal the antiviral mechanism of NSs and provides a theoretical basis for the search for new antiviral targets.


Asunto(s)
Actinas , Virus ARN , Proteínas no Estructurales Virales , Internalización del Virus , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Clatrina/metabolismo , Endocitosis/fisiología , Humanos , Virus ARN/metabolismo , Virus ARN/fisiología , Proteínas no Estructurales Virales/metabolismo
20.
Gels ; 8(6)2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35735718

RESUMEN

Recently, flexible sensors based on conductive hydrogels have been widely used in human health monitoring, human movement detection and soft robotics due to their excellent flexibility, high water content, good biocompatibility. However, traditional conductive hydrogels tend to freeze and lose their flexibility at low temperature, which greatly limits their application in a low temperature environment. Herein, according to the mechanism that multi-hydrogen bonds can inhibit ice crystal formation by forming hydrogen bonds with water molecules, we used butanediol (BD) and N-hydroxyethyl acrylamide (HEAA) monomer with a multi-hydrogen bond structure to construct LiCl/p(HEAA-co-BD) conductive hydrogel with antifreeze property. The results indicated that the prepared LiCl/p(HEAA-co-BD) conductive hydrogel showed excellent antifreeze property with a low freeze point of -85.6 °C. Therefore, even at -40 °C, the hydrogel can still stretch up to 400% with a tensile stress of ~450 KPa. Moreover, the hydrogel exhibited repeatable adhesion property (~30 KPa), which was attributed to the existence of multiple hydrogen bonds. Furthermore, a simple flexible sensor was fabricated by using LiCl/p(HEAA-co-BD) conductive hydrogel to detect compression and stretching responses. The sensor had excellent sensitivity and could monitor human body movement.

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