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1.
J Virol ; 98(2): e0134523, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38226815

RESUMO

Chronic hepatitis B virus (HBV) infection (CHB) is a risk factor for the development of liver fibrosis, cirrhosis, and hepatocellular carcinoma. Covalently closed circular DNA serves as the sole transcription template for all viral RNAs and viral transcription is driven and enhanced by viral promoter and enhancer elements, respectively. Interactions between transcription factors and these cis-elements regulate their activities and change the production levels of viral RNAs. Here, we report the identification of homeobox protein MSX-1 (MSX1) as a novel host restriction factor of HBV in liver. In both HBV-transfected and HBV-infected cells, MSX1 suppresses viral gene expression and genome replication. Mechanistically, MSX1 downregulates enhancer II/core promoter (EnII/Cp) activity via direct binding to an MSX1 responsive element within EnII/Cp, and such binding competes with hepatocyte nuclear factor 4α binding to EnII/Cp due to partial overlap between their respective binding sites. Furthermore, CHB patients in immune active phase express higher levels of intrahepatic MSX1 but relatively lower levels of serum and intrahepatic HBV markers compared to those in immune tolerant phase. Finally, MSX1 was demonstrated to induce viral clearance in two mouse models of HBV persistence, suggesting possible therapeutic potential for CHB.IMPORTANCECovalently closed circular DNA plays a key role for the persistence of hepatitis B virus (HBV) since it serves as the template for viral transcription. Identification of transcription factors that regulate HBV transcription not only provides insights into molecular mechanisms of viral life cycle regulation but may also provide potential antiviral targets. In this work, we identified host MSX1 as a novel restriction factor of HBV transcription. Meanwhile, we observed higher intrahepatic MSX1 expression in chronic hepatitis B virus (CHB) patients in immune active phase compared to those in immune tolerant phase, suggesting possible involvement of MSX1 in the regulation of HBV activity by the host. Lastly, intrahepatic overexpression of MSX1 delivered by recombinant adenoviruses into two mouse models of HBV persistence demonstrated MSX1-mediated repression of HBV in vivo, and MSX1-induced clearance of intrahepatic HBV DNA in treated mice suggested its potential as a therapeutic target for the treatment of CHB.


Assuntos
Hepatite B Crônica , Hepatite B , Fator de Transcrição MSX1 , Animais , Humanos , Camundongos , DNA Circular , DNA Viral/genética , Hepatite B/metabolismo , Vírus da Hepatite B/fisiologia , RNA Viral , Fatores de Transcrição/genética , Replicação Viral/genética , Fator de Transcrição MSX1/metabolismo
2.
BMC Genomics ; 25(1): 51, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212708

RESUMO

BACKGROUND: Colorectal cancer (CRC) is one of the world's most common malignancies. Epigenetics is the study of heritable changes in characteristics beyond the DNA sequence. Epigenetic information is essential for maintaining specific expression patterns of genes and the normal development of individuals, and disorders of epigenetic modifications may alter the expression of oncogenes and tumor suppressor genes and affect the development of cancer. This study elucidates the relationship between epigenetics and the prognosis of CRC patients by developing a predictive model to explore the potential value of epigenetics in the treatment of CRC. METHODS: Gene expression data of CRC patients' tumor tissue and controls were downloaded from GEO database. Combined with the 720 epigenetic-related genes (ERGs) downloaded from EpiFactors database, prognosis-related epigenetic genes were selected by univariate cox and LASSO analyses. The Kaplan-Meier and ROC curve were used to analyze the accuracy of the model. Data of 238 CRC samples with survival data downloaded from the GSE17538 were used for validation. Finally, the risk model is combined with the clinical characteristics of CRC patients to perform univariate and multivariate cox regression analysis to obtain independent risk factors and draw nomogram. Then we evaluated the accuracy of its prediction by calibration curves. RESULTS: A total of 2906 differentially expressed genes (DEGs) were identified between CRC and control samples. After overlapping DEGs with 720 ERGs, 56 epigenetic-related DEGs (DEERGs) were identified. Combining univariate and LASSO regression analysis, the 8 epigenetic-related genes-based risk score model of CRC was established. The ROC curves and survival difference of high and low risk groups revealed the good performance of the risk score model based on prognostic biomarkers in both training and validation sets. A nomogram with good performance to predict the survival of CRC patients were established based on age, NM stage and risk score. The calibration curves showed that the prognostic model had good predictive performance. CONCLUSION: In this study, an epigenetically relevant 8-gene signature was constructed that can effectively predict the prognosis of CRC patients and provide potential directions for targeted therapies for CRC.


Assuntos
Neoplasias Colorretais , Oncogenes , Humanos , Prognóstico , Nomogramas , Epigênese Genética , Estratificação de Risco Genético , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética
3.
Anal Chem ; 96(19): 7470-7478, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38696229

RESUMO

MicroRNAs (miRNAs) are endogenous and noncoding single-stranded RNA molecules with a length of approximately 18-25 nucleotides, which play an undeniable role in early cancer screening. Therefore, it is very important to develop an ultrasensitive and highly specific method for detecting miRNAs. Here, we present a bottom-up assembly approach for modifying glass microtubes with silica nanowires (SiNWs) and develop a label-free sensing platform for miRNA-21 detection. The three-dimensional (3D) networks formed by SiNWs make them abundant and highly accessible sites for binding with peptide nucleic acid (PNA). As a receptor, PNA has no phosphate groups and exhibits an overall electrically neutral state, resulting in a relatively small repulsion between PNA and RNA, which can improve the hybridization efficiency. The SiNWs-filled glass microtube (SiNWs@GMT) sensor enables ultrasensitive, label-free detection of miRNA-21 with a detection limit as low as 1 aM at a detection range of 1 aM-100 nM. Noteworthy, the sensor can still detect miRNA-21 in the range of 102-108 fM in complex solutions containing 1000-fold homologous interference of miRNAs. The high anti-interference performance of the sensor enables it to specifically recognize target miRNA-21 in the presence of other miRNAs and distinguish 1-, 3-mismatch nucleotide sequences. Significantly, the sensor platform is able to detect miRNA-21 in the lysate of breast cancer cell lines (e.g., MCF-7 cells and MDA-MB-231 cells), indicating that it has good potential in the screening of early breast cancers.


Assuntos
Vidro , MicroRNAs , Nanofios , Ácidos Nucleicos Peptídicos , Dióxido de Silício , MicroRNAs/análise , Ácidos Nucleicos Peptídicos/química , Dióxido de Silício/química , Humanos , Nanofios/química , Vidro/química , Técnicas Biossensoriais/métodos , Limite de Detecção
4.
Anal Chem ; 96(6): 2651-2657, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38306178

RESUMO

In vivo sensing of the dynamics of ions with high selectivity is essential for gaining molecular insights into numerous physiological and pathological processes. In this work, we report an ion-selective micropipette sensor (ISMS) through the integration of functional crown ether-encapsulated metal-organic frameworks (MOFs) synthesized in situ within the micropipette tip. The ISMS features distinctive sodium ion (Na+) conduction and high selectivity toward Na+ sensing. The selectivity is attributed to the synergistic effects of subnanoconfined space and the specific coordination of 18-crown-6 toward potassium ions (K+), which largely increase the steric hindrance and transport resistance for K+ to pass through the ISMS. Furthermore, the ISMS exhibits high stability and sensitivity, facilitating real-time monitoring of Na+ dynamics in the living rat brain during spreading of the depression events process. In light of the diversity of crown ethers and MOFs, we believe this study paves the way for a nanofluidic platform for in vivo sensing and neuromorphic electrochemical sensing.


Assuntos
Éteres de Coroa , Estruturas Metalorgânicas , Éteres de Coroa/química , Sódio/química , Íons/química , Potássio/química
5.
J Transl Med ; 22(1): 457, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745204

RESUMO

BACKGROUND AND PURPOSE: Interstitial lung disease (ILD) represents a significant complication of rheumatoid arthritis (RA) that lacks effective treatment options. This study aimed to investigate the intrinsic mechanism by which resveratrol attenuates rheumatoid arthritis complicated with interstitial lung disease through the AKT/TMEM175 pathway. METHODS: We established an arthritis model by combining chicken type II collagen and complete Freund's adjuvant. Resveratrol treatment was administered via tube feeding for 10 days. Pathological changes in both the joints and lungs were evaluated using HE and Masson staining techniques. Protein expression of TGF-ß1, AKT, and TMEM175 was examined in lung tissue. MRC-5 cells were stimulated using IL-1ß in combination with TGF-ß1 as an in vitro model of RA-ILD, and agonists of AKT, metabolic inhibitors, and SiRNA of TMEM175 were used to explore the regulation and mechanism of action of resveratrol RA-ILD. RESULTS: Resveratrol mitigates fibrosis in rheumatoid arthritis-associated interstitial lung disease and reduces oxidative stress and inflammation in RA-ILD. Furthermore, resveratrol restored cellular autophagy. When combined with the in vitro model, it was further demonstrated that resveratrol could suppress TGF-ß1 expression, and reduce AKT metamorphic activation, consequently inhibiting the opening of AKT/MEM175 ion channels. This, in turn, lowers lysosomal pH and enhances the fusion of autophagosomes with lysosomes, ultimately ameliorating the progression of RA-ILD. CONCLUSION: In this study, we demonstrated that resveratrol restores autophagic flux through the AKT/MEM175 pathway to attenuate inflammation as well as fibrosis in RA-ILD by combining in vivo and in vitro experiments. It further provides a theoretical basis for the selection of therapeutic targets for RA-ILD.


Assuntos
Artrite Reumatoide , Fibrose , Inflamação , Doenças Pulmonares Intersticiais , Proteínas Proto-Oncogênicas c-akt , Resveratrol , Transdução de Sinais , Resveratrol/farmacologia , Resveratrol/uso terapêutico , Artrite Reumatoide/complicações , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/complicações , Doenças Pulmonares Intersticiais/patologia , Doenças Pulmonares Intersticiais/metabolismo , Humanos , Inflamação/patologia , Inflamação/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismo , Proteínas de Membrana/metabolismo , Autofagia/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Linhagem Celular , Pulmão/patologia , Pulmão/efeitos dos fármacos , Masculino
6.
Diabetes Metab Res Rev ; 40(2): e3733, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37823338

RESUMO

The pathogenesis of diabetes is accompanied by increased levels of inflammatory factors, also known as "metabolic inflammation", which runs through the whole process of the occurrence and development of the disease. Mitochondria, as the key site of glucose and lipid metabolism, is often accompanied by mitochondrial function damage in type 2 diabetes mellitus (T2DM). Damaged mitochondria release pro-inflammatory factors through damage-related molecular patterns that activate inflammation pathways and reactions to oxidative stress, further aggravate metabolic disorders, and form a vicious circle. Currently, the pathogenesis of diabetes is still unclear, and clinical treatment focuses primarily on symptomatic intervention of the internal environment of disorders of glucose and lipid metabolism with limited clinical efficacy. The proinflammatory effect of mitochondrial damage-associated molecular pattern (mtDAMP) in T2DM provides a new research direction for exploring the pathogenesis and intervention targets of T2DM. Therefore, this review covers the most recent findings on the molecular mechanism and related signalling cascades of inflammation caused by mtDAMP in T2DM and discusses its pathogenic role of it in the pathological process of T2DM to search potential intervention targets.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Inflamação/metabolismo , Glucose/metabolismo , Transdução de Sinais
7.
Appl Microbiol Biotechnol ; 108(1): 213, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38358546

RESUMO

Type 2 diabetes mellitus (T2DM) was reported to be associated with impaired immune response and alterations in microbial composition and function. However, the underlying mechanism remains elusive. To investigate the association among retinoic acid-inducible gene-I-like receptors (RLRs) signaling pathway, intestinal bacterial microbiome, microbial tryptophan metabolites, inflammation, and a longer course of T2DM, 14 patients with T2DM and 7 healthy controls were enrolled. 16S rRNA amplicon sequencing and untargeted metabolomics were utilized to analyze the stool samples. RNA sequencing (RNA-seq) was carried out on the peripheral blood samples. Additionally, C57BL/6J specific pathogen-free (SPF) mice were used. It was found that the longer course of T2DM could lead to a decrease in the abundance of probiotics in the intestinal microbiome. In addition, the production of microbial tryptophan derivative skatole declined as a consequence of the reduced abundance of related intestinal microbes. Furthermore, low abundances of probiotics, such as Bacteroides and Faecalibacterium, could trigger the inflammatory response by activating the RLRs signaling pathway. The increased level of the member of TNF receptor-associated factors (TRAF) family, nuclear factor kappa-B (NF-κB) activator (TANK), in the animal colon activated nuclear factor kappa B subunit 2 (NFκB2), resulting in inflammatory damage. In summary, it was revealed that the low abundances of probiotics could activate the RLR signaling pathway, which could in turn activate its downstream signaling pathway, NF-κB, highlighting a relationship among gut microbes, inflammation, and a longer course of T2DM. KEY POINTS: Hyperglycemia may suppress tryptophanase activity. The low abundance of Bacteroides combined with the decrease of Dopa decarboxylase (DDC) activity may lead to the decrease of the production of tryptophan microbial derivative skatole, and the low abundance of Bacteroides or reduced skatole may further lead to the increase of blood glucose by downregulating the expression of glucagon-like peptide-1 (GLP1). A low abundance of anti-inflammatory bacteria may induce an inflammatory response by triggering the RLR signaling pathway and then activating its downstream NF-κB signaling pathway in prolonged T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Camundongos , Animais , Humanos , Camundongos Endogâmicos C57BL , NF-kappa B , RNA Ribossômico 16S/genética , Escatol , Triptofano , Inflamação , Bacteroides/genética
8.
Clin Exp Nephrol ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38536563

RESUMO

OBJECTIVES: This study aimed to develop machine learning models for risk prediction of continuous renal replacement therapy (CRRT) following coronary artery bypass grafting (CABG) surgery in intensive care unit (ICU) patients. METHODS: We extracted CABG patients from the electronic medical record system of the hospital. The endpoint of this study was the requirement for CRRT after CABG surgery. The Boruta method was used for feature selection. Seven machine learning algorithms were developed to train models and validated using 10 fold cross-validation (CV). Model discrimination and calibration were estimated using the area under the receiver operating characteristic curve (AUC) and calibration plot, respectively. We used the SHapley Additive exPlanations (SHAP) method to illustrate the effects of the features attributed to the model and analyze the effects of individual features on the output of the mode. RESULTS: In this study, 72 (37.89%) patients underwent CRRT, with a higher mortality compared to those patients without CRRT. The Gaussian Naïve Bayes (GNB) model with the highest AUC were considered as the final predictive model and performed best in predicting postoperative CRRT. The analysis of importance revealed that cardiac troponin T, creatine kinase isoenzyme, albumin, low-density lipoprotein cholesterol, NYHA, serum creatinine, and age were the top seven features of the GNB model. The SHAP force analysis illustrated how created model visualized individualized prediction of CRRT. CONCLUSIONS: Machine learning models were developed to predict CRRT. This contributes to the identification of risk variables for CRRT following CABG surgery in ICU patients and enables the optimization of perioperative managements for patients.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38655616

RESUMO

Vaccines play essential roles in the fight against the COVID-19 pandemic. The development and assessment of COVID-19 vaccines have generally focused on the induction and boosting of neutralizing antibodies targeting the SARS-CoV-2 spike (S) protein. Due to rapid and continuous variation in the S protein, such vaccines need to be regularly updated to match newly emerged dominant variants. T-cell vaccines that target MHC I- or II-restricted epitopes in both structural and non-structural viral proteins have the potential to induce broadly cross-protective and long-lasting responses. In this work, the entire proteome encoded by SARS-CoV-2 (Wuhan-hu-1) is subjected to immunoinformatics-based prediction of HLA-A*02:01-restricted epitopes. The immunogenicity of the predicted epitopes is evaluated using peripheral blood mononuclear cells from convalescent Wuhan-hu-1-infected patients. Furthermore, predicted epitopes that are conserved across major SARS-CoV-2 lineages and variants are used to construct DNA vaccines expressing multi-epitope polypeptides. Most importantly, two DNA vaccine constructs induce epitope-specific CD8 + T-cell responses in a mouse model of HLA-A*02:01 restriction and protect immunized mice from challenge with Wuhan-hu-1 virus after hACE2 transduction. These data provide candidate T-cell epitopes useful for the development of T-cell vaccines against SARS-CoV-2 and demonstrate a strategy for quick T-cell vaccine candidate development applicable to other emerging pathogens.

10.
Pestic Biochem Physiol ; 201: 105899, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685208

RESUMO

This study investigated the function of the MDR49 gene in Aedes aegypti. MDR49 mutants were constructed using CRISPR/Cas9 technology; the mutation led to increased sensitivity to ivermectin (LC50: from 1.3090 mg L-1 to 0.5904 mg L-1), and a reduction in midgut trypsin activity. These findings suggest that the P-gp encoded by MDR49 confers resistance to ivermectin and impacts the reproductive function in Ae. aegypti. RNA interference technology showed that knockdown of MDR49 gene resulted in a significant decrease in the expression of VGA1 after a blood meal, as well as a decrease in the number of eggs laid and their hatching rate. LC-MS revealed that following ivermectin treatment, the MDR493d+2s/3d+2s strain larvae exhibited significantly higher drug concentrations in the head and fat body compared to the wild type. Modeling of inward-facing P-gp and molecular docking found almost no difference in the affinity of P-gp for ivermectin before and after the mutation. However, modeling of the outward-facing conformation demonstrated that the flexible linker loop between TM5 and TM6 of P-gp undergoes changes after the mutation, resulting in a decrease in trypsin activity and an increase in sensitivity to ivermectin. These results provide useful insights into ivermectin resistance and the other roles played by the MDR49 gene.


Assuntos
Aedes , Proteínas de Insetos , Ivermectina , Animais , Aedes/efeitos dos fármacos , Aedes/genética , Aedes/metabolismo , Ivermectina/farmacologia , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Tripsina/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Fertilidade/efeitos dos fármacos , Resistência a Inseticidas/genética , Inibidores da Tripsina/metabolismo , Inibidores da Tripsina/farmacologia , Simulação de Acoplamento Molecular , Inseticidas/farmacologia
11.
Mikrochim Acta ; 191(6): 341, 2024 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795199

RESUMO

The construction of gating system in artificial channels is a cutting-edge research direction in understanding biological process and application sensing. Here, by mimicking the gating system, we report a device that easily synthesized single-glass micropipettes functionalized by three-dimensional (3D) DNA network, which triggers the gating mechanism for the detection of biomolecules. Based on this strategy, the gating mechanism shows that single-glass micropipette assembled 3D DNA network is in the "OFF" state, and after collapsing in the presence of ATP, they are in the "ON" state, at which point they exhibit asymmetric response times. In the "ON" process of the gating mechanism, the ascorbic acid phosphate (AAP) can be encapsulated by a 3D DNA network and released in the presence of adenosine triphosphate (ATP), which initiates a catalyzed cascade reaction under the influence of alkaline phosphatase (ALP). Ultimately, the detection of ALP can be responded to form the fluorescence signal generated by terephthalic acid that has captured hydroxyl radicals, which has a detection range of 0-250 mU/mL and a limit of detection of 50 mU/mL. This work provides a brand-new way and application direction for research of gating mechanism.


Assuntos
Trifosfato de Adenosina , Fosfatase Alcalina , DNA , Trifosfato de Adenosina/análise , Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/química , DNA/química , Vidro/química , Técnicas Biossensoriais/métodos , Limite de Detecção , Ácido Ascórbico/química , Ácido Ascórbico/análogos & derivados
12.
J Sci Food Agric ; 104(9): 5052-5063, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38284744

RESUMO

BACKGROUND: Postmenopausal osteoporosis (PMO) is associated with dysregulation of bone metabolism and gut microbiota. Quinoa is a grain with high nutritional value, and its effects and potential mechanisms on PMO have not been reported yet. Therefore, the purpose of this study is to investigate the bone protective effect of quinoa on ovariectomy (OVX) rats by regulating bone metabolism and gut microbiota. RESULTS: Quinoa significantly improved osteoporosis-related biochemical parameters of OVX rats and ameliorated ovariectomy-induced bone density reduction and trabecular structure damage. Quinoa intervention may repair the intestinal barrier by upregulating the expression of tight junction proteins in the duodenum. In addition, quinoa increased the levels of Firmicutes, and decreased the levels of Bacteroidetes and Prevotella, reversing the dysregulation of the gut microbiota. This may be related to estrogen signaling pathway, secondary and primary bile acid biosynthesis, benzoate degradation, synthesis and degradation of ketone bodies, NOD-like receptor signaling pathway and biosynthesis of tropane, piperidine and pyridine alkaloids. Correlation analysis showed that there is a strong correlation between gut microbiota with significant changes in abundance and parameters related to osteoporosis. CONCLUSION: Quinoa could significantly reverse the high intestinal permeability and change the composition of gut microbiota in OVX rats, thereby improving bone microstructure deterioration and bone metabolism disorder, and ultimately protecting the bone loss of OVX rats. © 2024 Society of Chemical Industry.


Assuntos
Densidade Óssea , Chenopodium quinoa , Microbioma Gastrointestinal , Ovariectomia , Ratos Sprague-Dawley , Animais , Ratos , Feminino , Chenopodium quinoa/química , Densidade Óssea/efeitos dos fármacos , Humanos , Bactérias/classificação , Bactérias/metabolismo , Bactérias/isolamento & purificação , Bactérias/genética , Osteoporose/metabolismo , Osteoporose/prevenção & controle , Osteoporose Pós-Menopausa/metabolismo , Osteoporose Pós-Menopausa/prevenção & controle , Osteoporose Pós-Menopausa/microbiologia
13.
Angew Chem Int Ed Engl ; 63(7): e202316161, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38165062

RESUMO

Biological ion channels use the synergistic effects of various strategies to realize highly selective ion sieving. For example, potassium channels use functional groups and angstrom-sized pores to discriminate rival ions and enrich target ions. Inspired by this, we constructed a layered crystal pillared by crown ether that incorporates these strategies to realize high Li+ selectivity. The pillared channels and crown ether have an angstrom-scale size. The crown ether specifically allows the low-barrier transport of Li+ . The channels attract and enrich Li+ ions by up to orders of magnitude. As a result, our material sieves Li+ out of various common ions such as Na+ , K+ , Ca2+ , Mg2+ and Al3+ . Moreover, by spontaneously enriching Li+ ions, it realizes an effective Li+ /Na+ selectivity of 1422 in artificial seawater where the Li+ concentration is merely 25 µM. We expect this work to spark technologies for the extraction of lithium and other dilute metal ions.

14.
Angew Chem Int Ed Engl ; 63(25): e202405863, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38589298

RESUMO

Cascade radical cyclization constitutes an atom- and step-economic route for rapid assembly of polycyclic molecular skeletons. Although an array of redox-active metal catalysts has recently shown robust applications in enabling various catalytic cascade radical processes, the use of free organic radical as the catalyst, which is capable of triggering strategically distinct cascades, has rarely been developed. Here, we disclosed that the benzimidazolium-based N-heterocyclic carbene (NHC)-boryl radical is capable of catalyzing cascade cyclization reactions in both intra- and intermolecular pathways, assembling [5,5] fused bicyclic and [6,6,6] fused tricyclic molecules, respectively. The catalytic reactions start with the chemo- and regioselective addition of the boryl radical catalyst to a tethered alkene or alkyne moiety, followed by either an intramolecular formal [3+2] or an intermolecular [2+2+2] cycloaddition process to construct bicyclo[3.3.0]octane or tetrahydrophenanthridine skeletons, respectively. Eventually, a ß-elimination occurs to release the boryl radical catalyst, completing a catalytic cycle. High to excellent diastereoselectivity is achieved in both catalytic reactions under substrate control.

15.
J Med Virol ; 95(8): e28995, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37522259

RESUMO

BK polyomavirus (BKV) is a small non-enveloped DNA virus. BKV infection or reactivation may cause BKV-associated nephropathy and hemorrhagic cystitis in immunosuppressed transplant recipients. No effective antivirals or prevention strategies are available against BKV infections. The current BKV reverse system employs the transfection of purified full-length linear viral genomes released by enzyme digestion from BKV genomic plasmids. The method is laborious and often results in variable DNA yield and quality, which can affect the efficiency of transfection and subsequent formation of circular viral genomes in cells. In this study, we report the generation of circular viral genomes by Cre-mediated DNA recombination in cells directly transfected with BKV precursor genomic plasmids. The novel system supported efficient viral expression and replication, and produced a higher level of infectious virions compared with the transfection with linear BKV genomes. Furthermore, we successfully constructed recombinant BKV capable of reporter gene expression. In conclusion, the novel BKV reverse genetic system allows for simpler manipulation of BKV genome with better virus yield, providing a tool for the study of BKV life cycle and antiviral screening.


Assuntos
Vírus BK , Transplante de Rim , Infecções por Polyomavirus , Infecções Tumorais por Vírus , Humanos , Vírus BK/genética , Genética Reversa , DNA
16.
J Med Virol ; 95(9): e29062, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37665238

RESUMO

Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA), the transcription template for all viral mRNAs, is highly stable and current treatment options cannot effectively induce its clearance. Previously, we established an HBV persistence mouse model based on a clinical isolate (termed BPS) and identified interleukin-21 (IL-21) as a potent inducer of HBV clearance. Lipid nanoparticle (LNP) mediated delivery of mRNA has proven to be a highly safe and effective delivery platform. This work explored the applicability and effectiveness of the mRNA-LNP platform in IL-21-based HBV therapies. First, LNP-encapsulated murine IL-21 mRNA (LNP-IL-21) was prepared, characterized, and demonstrated to engender IL-21 expression in vitro and in vivo. Next, LNP-IL-21 was shown to induce clearance of both serum and intrahepatic HBV antigen and DNA in two HBV persistence mouse models based on BPS and recombinant cccDNA (rcccDNA), respectively, which was associated with HBV-specific humoral and cellular immune responses. Furthermore, peripheral blood mononuclear cells from BPS persistence mice treated ex vivo with LNP-IL-21 and HBV surface antigen (HBsAg) could induce similar HBV clearance upon infusion into recipient mice. These findings indicated that IL-21 combined with mRNA-LNP platform represents a valid and promising strategy for developing novel therapeutics against chronic HBV infection.


Assuntos
Vírus da Hepatite B , Leucócitos Mononucleares , Animais , Camundongos , Vírus da Hepatite B/genética , Antígenos de Superfície da Hepatite B/genética , Modelos Animais de Doenças , RNA Mensageiro
17.
Langmuir ; 39(12): 4537-4543, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36926892

RESUMO

By combining DNA nanotechnology and solid-phase nanopore technology, the aggregation behavior of polymer guided by a single-molecular poly(propylene) (PPO) nucleus in a 3D DNA network has been studied. At low temperature, the PPO chain is evenly dispersed in the rigid 3D DNA network; at higher temperature, the PPO chain self-collapses to a single-molecular nucleus; and upon addition of amphiphilic block copolymers below the critical micelle concentration (CMC), the chains tend to aggregate on the isolated hydrophobic nucleus through intermolecular hydrophobic interactions. The process has been characterized by a rheological test and an electrochemical test. This study not only provides a preliminary understanding of the nucleation and growth process of block copolymers but also offers a theoretical basis for the study of protein self-folding and aggregation in the future. On this basis, utilizing this nucleation and growth event, a novel smart nanopore has been developed for hydrophobicity-dependent molecular transport.

18.
Microb Ecol ; 86(4): 2981-2992, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37684546

RESUMO

As one of the low-carbon and high-efficient energy sources, nuclear power is developing vigorously to alleviate the crisis of global climate warming and realize carbon neutrality goals. Meanwhile, the ecological effect of thermal drainage in the nuclear power plant is significantly remarkable, which environmental assessment system has not yet referred to microorganisms. The rapid response of microbial diversity and community structure to environmental changes is crucial for ecosystem stability. This study investigated the bacterial diversity, community construction, and the co-occurrence patterns by 16S rRNA gene amplicon sequencing among gradient warming regions in Tianwan Nuclear Power Plant. The alpha diversity of the high warming region was the lowest in summer, which was dominated by Proteobacteria, whereas the highest bacterial diversity presented in high warming regions in winter, which harbored higher proportions of Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes. The spatial distribution of bacterial communities showed clear separation especially in summer. Strong correlations were between community compositions and environmental factors, such as salinity, DO, TN, and temperature in summer. Furthermore, remarkable seasonality in bacterial co-occurrence patterns was discovered: the robustness of the bacterial co-occurrence network was promoted in winter, while the complexity and robustness were decreased in summer due to the warming of thermal drainage. These findings reveal the potential factors underpinning the influence of thermal drainage on bacterial community structure, which make it possible to predict the ecological effect of the nuclear power plants by exploring how the microbial assembly is likely to respond to the temperature and other environmental changes.


Assuntos
Ecossistema , Centrais Nucleares , RNA Ribossômico 16S/genética , Bactérias/genética , Drenagem , Carbono
19.
Inorg Chem ; 62(24): 9508-9517, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37296395

RESUMO

A new Yb-based three-dimensional metal-organic framework with free Lewis basic sites, [Yb2(ddbpdc)3(CH3OH)2] (referred to as ACBP-6), from YbCl3 and (6R,8R)-6,8-dimethyl-7,8-dihydro-6H-[1,5]dioxonino[7,6-b:8,9-b']dipyridine-3,11-dicarboxylic acid (H2ddbpdc) was synthesized by a conventional solvothermal method. Two Yb3+ are connected by three carboxyl groups to form the [Yb2(CO2)5] binuclear unit, which is further bridged by two carboxyl moieties to produce a tetranuclear secondary building unit. With further ligation of the ligand ddbpdc2-, a 3-D MOF with helical channels is constructed. In the MOF, Yb3+ only coordinates with O atoms, leaving the bipyridyl N atoms of ddbpdc2- unoccupied. The unsaturated Lewis basic sites make this framework possible to coordinate with other metal ions. After growing the ACBP-6 in situ into a glass micropipette, a novel current sensor is formed. This sensor shows high selectivity and a high signal-to-noise ratio toward Cu2+ detection with a detection limit of 1 µM, due to the stronger coordination ability between the Cu2+ and the bipyridyl N atoms.

20.
J Pharmacol Sci ; 152(4): 210-219, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37344056

RESUMO

Aberrant intestinal epithelial barrier function is the primary pathology of Ulcerative colitis (UC), making it a desirable drug target. In this study, our small-molecule compound AI-34 exerted a significant protective effect in an LPS-induced epithelial barrier injury model. In vitro, AI-34 treatment significantly decreased cell permeability, increased transmembrane resistance, and maintained the junctional protein (ZO-1 and E-cadherin) levels in monolayer cells. Using the LiP-small molecule mapping approach (LiP-SMap), we demonstrated that AI-34 binds to 14-3-3ζ. AI-34 promoted the interaction between 14-3-3ζ and ß-catenin, decreasing the ubiquitination of ß-catenin and thus maintaining intestinal epithelial barrier function. Finally, AI-34 triggered the stabilization of ß-catenin mediated by 14-3-3ζ, provoking a significant improvement in the DSS-induced colitis model. Our findings suggest that AI-34 may be a promising candidate for UC treatment.


Assuntos
Colite Ulcerativa , Colite , Animais , Camundongos , Proteínas 14-3-3 , beta Catenina/metabolismo , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Modelos Animais de Doenças , Mucosa Intestinal , Camundongos Endogâmicos C57BL
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