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1.
PLoS Pathog ; 20(5): e1012279, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38814988

RESUMO

The influenza A virus (IAV) consists of 8 single-stranded, negative-sense viral RNA (vRNA) segments. After infection, vRNA is transcribed, replicated, and wrapped by viral nucleoprotein (NP) to form viral ribonucleoprotein (vRNP). The transcription, replication, and nuclear export of the viral genome are regulated by the IAV protein, NS2, which is translated from spliced mRNA transcribed from viral NS vRNA. This splicing is inefficient, explaining why NS2 is present in low abundance after IAV infection. The levels of NS2 and its subsequent accumulation are thought to influence viral RNA replication and vRNP nuclear export. Here we show that NS2 is ubiquitinated at the K64 and K88 residues by K48-linked and K63-linked polyubiquitin (polyUb) chains, leading to the degradation of NS2 by the proteasome. Additionally, we show that a host deubiquitinase, OTUB1, can remove polyUb chains conjugated to NS2, thereby stabilizing NS2. Accordingly, knock down of OTUB1 by siRNA reduces the nuclear export of vRNP, and reduces the overall production of IAV. These results collectively demonstrate that the levels of NS2 in IAV-infected cells are regulated by a ubiquitination-deubiquitination system involving OTUB1 that is necessary for optimal IAV replication.


Assuntos
Cisteína Endopeptidases , Vírus da Influenza A , Proteínas não Estruturais Virais , Replicação Viral , Animais , Cães , Humanos , Cisteína Endopeptidases/metabolismo , Cisteína Endopeptidases/genética , Enzimas Desubiquitinantes/metabolismo , Células HEK293 , Vírus da Influenza A/metabolismo , Influenza Humana/metabolismo , Influenza Humana/virologia , RNA Viral/metabolismo , RNA Viral/genética , Ubiquitinação , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/genética , Replicação Viral/fisiologia , Linhagem Celular , Células Vero , Chlorocebus aethiops
2.
EMBO Rep ; 25(5): 2441-2478, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38649663

RESUMO

Ago2 differentially regulates oncogenic and tumor-suppressive miRNAs in cancer cells. This discrepancy suggests a secondary event regulating Ago2/miRNA action in a context-dependent manner. We show here that a positive charge of Ago2 K212, that is preserved by SIR2-mediated Ago2 deacetylation in cancer cells, is responsible for the direct interaction between Ago2 and Caveolin-1 (CAV1). Through this interaction, CAV1 sequesters Ago2 on the plasma membranes and regulates miRNA-mediated translational repression in a compartment-dependent manner. Ago2/CAV1 interaction plays a role in miRNA-mediated mRNA suppression and in miRNA release via extracellular vesicles (EVs) from tumors into the circulation, which can be used as a biomarker of tumor progression. Increased Ago2/CAV1 interaction with tumor progression promotes aggressive cancer behaviors, including metastasis. Ago2/CAV1 interaction acts as a secondary event in miRNA-mediated suppression and increases the complexity of miRNA actions in cancer.


Assuntos
Proteínas Argonautas , Caveolina 1 , MicroRNAs , Metástase Neoplásica , Animais , Humanos , Camundongos , Proteínas Argonautas/metabolismo , Proteínas Argonautas/genética , Caveolina 1/metabolismo , Caveolina 1/genética , Linhagem Celular Tumoral , Vesículas Extracelulares/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , MicroRNAs/genética , Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/patologia , Ligação Proteica , Sirtuína 2/metabolismo , Sirtuína 2/genética
3.
Proc Natl Acad Sci U S A ; 120(11): e2214834120, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36893272

RESUMO

Human cortical expansion has occurred non-uniformly across the brain. We assessed the genetic architecture of cortical global expansion and regionalization by comparing two sets of genome-wide association studies of 24 cortical regions with and without adjustment for global measures (i.e., total surface area, mean cortical thickness) using a genetically informed parcellation in 32,488 adults. We found 393 and 756 significant loci with and without adjusting for globals, respectively, where 8% and 45% loci were associated with more than one region. Results from analyses without adjustment for globals recovered loci associated with global measures. Genetic factors that contribute to total surface area of the cortex particularly expand anterior/frontal regions, whereas those contributing to thicker cortex predominantly increase dorsal/frontal-parietal thickness. Interactome-based analyses revealed significant genetic overlap of global and dorsolateral prefrontal modules, enriched for neurodevelopmental and immune system pathways. Consideration of global measures is important in understanding the genetic variants underlying cortical morphology.


Assuntos
Estudo de Associação Genômica Ampla , Imageamento por Ressonância Magnética , Adulto , Humanos , Córtex Cerebral/anatomia & histologia , Córtex Pré-Frontal , Encéfalo
4.
Hepatology ; 80(2): 428-439, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38436992

RESUMO

BACKGROUND AND AIMS: A single-nation study reported that pretreatment HBV viral load is associated with on-treatment risk of HCC in patients who are HBeAg-positive without cirrhosis and with chronic hepatitis B initiating antiviral treatment. We aimed to validate the association between baseline HBV viral load and on-treatment HCC risk in a larger, multinational cohort. APPROACH AND RESULTS: Using a multinational cohort from Korea, Hong Kong, and Taiwan involving 7545 adult patients with HBeAg-positive, without cirrhosis and with chronic hepatitis B who started entecavir or tenofovir treatment with baseline HBV viral load ≥5.00 log 10 IU/mL, HCC risk was estimated by baseline viral load. HBV viral load was analyzed as a categorical variable. During continuous antiviral treatment (median, 4.28 y), HCC developed in 200 patients (incidence rate, 0.61 per 100 person-years). Baseline HBV DNA level was independently associated with on-treatment HCC risk in a nonlinear pattern. HCC risk was lowest with the highest baseline viral load (≥8.00 log 10 IU/mL; incidence rate, 0.10 per 100 person-years), but increased sharply as baseline viral load decreased. The adjusted HCC risk was 8.05 times higher (95% CI, 3.34-19.35) with baseline viral load ≥6.00 and <7.00 log 10 IU/mL (incidence rate, 1.38 per 100 person-years) compared with high (≥8.00 log 10 IU/mL) baseline viral load ( p <0.001). CONCLUSIONS: In a multinational cohort of adult patients with HBeAg-positive without cirrhosis and with chronic hepatitis B, baseline HBV viral load was significantly associated with HCC risk despite antiviral treatment. Patients with the highest viral load who initiated treatment had the lowest long-term risk of HCC development.


Assuntos
Antivirais , Carcinoma Hepatocelular , Antígenos E da Hepatite B , Hepatite B Crônica , Neoplasias Hepáticas , Carga Viral , Humanos , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/complicações , Hepatite B Crônica/virologia , Masculino , Neoplasias Hepáticas/virologia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Feminino , Pessoa de Meia-Idade , Antígenos E da Hepatite B/sangue , Antivirais/uso terapêutico , Carcinoma Hepatocelular/virologia , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Adulto , Taiwan/epidemiologia , Vírus da Hepatite B , Hong Kong/epidemiologia , República da Coreia/epidemiologia , Estudos de Coortes , Tenofovir/uso terapêutico , Guanina/análogos & derivados , Guanina/uso terapêutico , DNA Viral/sangue , Incidência , Fatores de Risco
5.
Nature ; 573(7775): 595-599, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31534224

RESUMO

The tumour suppressor TP53 is mutated in the majority of human cancers, and in over 70% of pancreatic ductal adenocarcinoma (PDAC)1,2. Wild-type p53 accumulates in response to cellular stress, and regulates gene expression to alter cell fate and prevent tumour development2. Wild-type p53 is also known to modulate cellular metabolic pathways3, although p53-dependent metabolic alterations that constrain cancer progression remain poorly understood. Here we find that p53 remodels cancer-cell metabolism to enforce changes in chromatin and gene expression that favour a premalignant cell fate. Restoring p53 function in cancer cells derived from KRAS-mutant mouse models of PDAC leads to the accumulation of α-ketoglutarate (αKG, also known as 2-oxoglutarate), a metabolite that also serves as an obligate substrate for a subset of chromatin-modifying enzymes. p53 induces transcriptional programs that are characteristic of premalignant differentiation, and this effect can be partially recapitulated by the addition of cell-permeable αKG. Increased levels of the αKG-dependent chromatin modification 5-hydroxymethylcytosine (5hmC) accompany the tumour-cell differentiation that is triggered by p53, whereas decreased 5hmC characterizes the transition from premalignant to de-differentiated malignant lesions that is associated with mutations in Trp53. Enforcing the accumulation of αKG in p53-deficient PDAC cells through the inhibition of oxoglutarate dehydrogenase-an enzyme of the tricarboxylic acid cycle-specifically results in increased 5hmC, tumour-cell differentiation and decreased tumour-cell fitness. Conversely, increasing the intracellular levels of succinate (a competitive inhibitor of αKG-dependent dioxygenases) blunts p53-driven tumour suppression. These data suggest that αKG is an effector of p53-mediated tumour suppression, and that the accumulation of αKG in p53-deficient tumours can drive tumour-cell differentiation and antagonize malignant progression.


Assuntos
Carcinoma Ductal Pancreático , Diferenciação Celular/genética , Ácidos Cetoglutáricos/metabolismo , Neoplasias Pancreáticas , Proteína Supressora de Tumor p53/metabolismo , Animais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/fisiopatologia , Linhagem Celular Tumoral , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Montagem e Desmontagem da Cromatina/genética , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Ácidos Cetoglutáricos/farmacologia , Camundongos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/fisiopatologia , Ligação Proteica , Ácido Succínico/metabolismo , Ativação Transcricional
6.
Proc Natl Acad Sci U S A ; 119(10): e2115627119, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35238668

RESUMO

SignificanceThe magnitude of the CO2 fertilization effect on terrestrial photosynthesis is uncertain because it is not directly observed and is subject to confounding effects of climatic variability. We apply three well-established eco-evolutionary optimality theories of gas exchange and photosynthesis, constraining the main processes of CO2 fertilization using measurable variables. Using this framework, we provide robust observationally inferred evidence that a strong CO2 fertilization effect is detectable in globally distributed eddy covariance networks. Applying our method to upscale photosynthesis globally, we find that the magnitude of the CO2 fertilization effect is comparable to its in situ counterpart but highlight the potential for substantial underestimation of this effect in tropical forests for many reflectance-based satellite photosynthesis products.

7.
Proc Natl Acad Sci U S A ; 119(17): e2110557119, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35442775

RESUMO

Anticancer drug development campaigns often fail due to an incomplete understanding of the therapeutic index differentiating the efficacy of the agent against the cancer and its on-target toxicities to the host. To address this issue, we established a versatile preclinical platform in which genetically defined cancers are produced using somatic tissue engineering in transgenic mice harboring a doxycycline-inducible short hairpin RNA against the target of interest. In this system, target inhibition is achieved by the addition of doxycycline, enabling simultaneous assessment of efficacy and toxicity in the same animal. As proof of concept, we focused on CDK9­a cancer target whose clinical development has been hampered by compounds with poorly understood target specificity and unacceptable toxicities. We systematically compared phenotypes produced by genetic Cdk9 inhibition to those achieved using a recently developed highly specific small molecule CDK9 inhibitor and found that both perturbations led to robust antitumor responses. Remarkably, nontoxic levels of CDK9 inhibition could achieve significant treatment efficacy, and dose-dependent toxicities produced by prolonged CDK9 suppression were largely reversible upon Cdk9 restoration or drug withdrawal. Overall, these results establish a versatile in vivo target validation platform that can be employed for rapid triaging of therapeutic targets and lend support to efforts aimed at advancing CDK9 inhibitors for cancer therapy.


Assuntos
Antineoplásicos , Neoplasias , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Quinase 9 Dependente de Ciclina/metabolismo , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Interferência de RNA
8.
BMC Biol ; 22(1): 136, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38867239

RESUMO

BACKGROUND: Most tail-anchored (TA) membrane proteins are delivered to the endoplasmic reticulum through a conserved posttranslational pathway. Although core mechanisms underlying the targeting and insertion of TA proteins are well established in eukaryotes, their role in mediating TA protein biogenesis in plants remains unclear. We reported the crystal structures of algal arsenite transporter 1 (ArsA1), which possesses an approximately 80-kDa monomeric architecture and carries chloroplast-localized TA proteins. However, the mechanistic basis of ArsA2, a Get3 (guided entry of TA proteins 3) homolog in plants, for TA recognition remains unknown. RESULTS: Here, for the first time, we present the crystal structures of the diatom Pt-Get3a that forms a distinct ellipsoid-shaped tetramer in the open (nucleotide-bound) state through crystal packing. Pulldown assay results revealed that only tetrameric Pt-Get3a can bind to TA proteins. The lack of the conserved zinc-coordination CXXC motif in Pt-Get3a potentially leads to the spontaneous formation of a distinct parallelogram-shaped dimeric conformation in solution, suggesting a new dimer state for subsequent tetramerization upon TA targeting. Pt-Get3a nonspecifically binds to different subsets of TA substrates due to the lower hydrophobicity of its α-helical subdomain, which is implicated in TA recognition. CONCLUSIONS: Our study provides new insights into the mechanisms underlying TA protein shielding by tetrameric Get3 during targeting to the diatom's cell membrane.


Assuntos
Diatomáceas , Diatomáceas/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/genética , Multimerização Proteica
9.
Infect Immun ; 92(8): e0019324, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-38990045

RESUMO

Immunoglobulin A1 (IgA1) protease is a critical virulence factor of Haemophilus influenzae that facilitates bacterial mucosal infection. This study investigates the effect of iga gene polymorphism on the enzymatic activity of H. influenzae IgA1 protease. The IgA1 protease activity was examined in the H. influenzae Rd KW20 strain and 51 isolates. Genetic variations in iga and deduced amino acid substitutions affecting IgA1 protease activity were assessed. Machine learning tools and functional complementation assays were used to analyze the effects of identified substitutions on the stability and activity of IgA1 protease, respectively. All 51 isolates exhibited similar iga expression levels. No igaB expression was detected. According to comparisons with the reference Rd KW20 strain, four substitutions in the protease domain, 26 in the nonprotease passenger domain, and two in the ß-barrel domain were associated with the change in IgA1 protease activity. No substitutions in the catalytic site of IgA1 protease were observed. Logistic regression, receiver operating characteristic curves, Venn diagrams, and protein stability analyses revealed that the substitutions Asn352Lys, Pro353Ala, Lys356Asn, Gln916Lys, and Gly917Ser, which were located in the nonactive site of the passenger domain, were associated with decreases in IgA1 protease activity and stability, whereas Asn914Lys was associated with an increase in these events. Functional complementation assays revealed that the Asn914Lys substitution increased IgA1 protease activity in the Rd KW20 strain. This study identified substitutions in the nonactive site of the passenger domain that affect both the activity and stability of H. influenzae IgA1 protease.


Assuntos
Haemophilus influenzae , Haemophilus influenzae/genética , Haemophilus influenzae/enzimologia , Humanos , Substituição de Aminoácidos , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Serina Endopeptidases/química , Imunoglobulina A/metabolismo , Infecções por Haemophilus/microbiologia , Infecções por Haemophilus/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química
10.
Gene Ther ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39232211

RESUMO

SLC26A4 encodes pendrin, a crucial anion exchanger essential for maintaining hearing function. Mutations in SLC26A4, including the prevalent c.919-2 A > G splice-site mutation among East Asian individuals, can disrupt inner ear electrolyte balance, leading to syndromic and non-syndromic hearing loss, such as Pendred syndrome and DFNB4. To explore potential therapeutic strategies, we utilized CRISPR/Cas9-mediated exon skipping to create a Slc26a4∆E8+E9/∆E8+E9 mouse model. We assessed pendrin expression in the inner ear and evaluated vestibular and auditory functions. The Slc26a4∆E8+E9/∆E8+E9 mice demonstrated reframed pendrin in the inner ear and normal vestibular functions, contrasting with severely abnormal vestibular functions observed in the Slc26a4 c.919-2 A > G splicing mutation mouse model. However, despite these molecular achievements, hearing function did not show the expected improvement, consistent with observed pathology, including cochlear hair cell loss and elevated hearing thresholds. Consequently, our findings highlight the necessity for alternative genetic editing strategies to address hearing loss caused by the SLC26A4 c.919-2 A > G mutation.

11.
J Am Chem Soc ; 146(29): 20009-20018, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38980280

RESUMO

High-throughput computational materials discovery has promised significant acceleration of the design and discovery of new materials for many years. Despite a surge in interest and activity, the constraints imposed by large-scale computational resources present a significant bottleneck. Furthermore, examples of very large-scale computational discovery carried out through experimental validation remain scarce, especially for materials with product applicability. Here, we demonstrate how this vision became reality by combining state-of-the-art machine learning (ML) models and traditional physics-based models on cloud high-performance computing (HPC) resources to quickly navigate through more than 32 million candidates and predict around half a million potentially stable materials. By focusing on solid-state electrolytes for battery applications, our discovery pipeline further identified 18 promising candidates with new compositions and rediscovered a decade's worth of collective knowledge in the field as a byproduct. We then synthesized and experimentally characterized the structures and conductivities of our top candidates, the NaxLi3-xYCl6 (0≤ x≤ 3) series, demonstrating the potential of these compounds to serve as solid electrolytes. Additional candidate materials that are currently under experimental investigation could offer more examples of the computational discovery of new phases of Li- and Na-conducting solid electrolytes. The showcased screening of millions of materials candidates highlights the transformative potential of advanced ML and HPC methodologies, propelling materials discovery into a new era of efficiency and innovation.

12.
Curr Issues Mol Biol ; 46(6): 6267-6283, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38921045

RESUMO

Autoantibodies against apolipoprotein A-I (ApoA-I) are associated with cardiovascular disease risks. We aimed to examine the 4-hydroxy-2-nonenal (HNE) modification of ApoA-I in coronary artery disease (CAD) and evaluate the potential risk of autoantibodies against their unmodified and HNE-modified peptides. We assessed plasma levels of ApoA-I, HNE-protein adducts, and autoantibodies against unmodified and HNE-peptide adducts, and significant correlations and odds ratios (ORs) were examined. Two novel CAD-specific HNE-peptide adducts, ApoA-I251-262 and ApoA-I70-83, were identified. Notably, immunoglobulin G (IgG) anti-ApoA-I251-262 HNE, IgM anti-ApoA-I70-83 HNE, IgG anti-ApoA-I251-262, IgG anti-ApoA-I70-83, and HNE-protein adducts were significantly correlated with triglycerides, creatinine, or high-density lipoprotein in CAD with various degrees of stenosis (<30% or >70%). The HNE-protein adduct (OR = 2.208-fold, p = 0.020) and IgM anti-ApoA-I251-262 HNE (2.046-fold, p = 0.035) showed an increased risk of progression from >30% stenosis in CAD. HNE-protein adducts and IgM anti-ApoA-I251-262 HNE may increase the severity of CAD at high and low levels, respectively.

13.
Hum Genet ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985322

RESUMO

The prevalence of overweight and obesity is increasing, leading to metabolic-associated fatty liver disease (MAFLD) characterized by excessive accumulation of liver fat and a risk of developing hepatocellular carcinoma (HCC). The driver gene mutations may play the roles of passengers that occur in single 'hotspots' and can promote tumorigenesis from benign to malignant lesions. We investigated the impact of high body weight and BMI on HCC survival using The Cancer Genome Atlas Liver Hepatocellular Carcinoma (TCGA-LIHC) dataset. To explore the effects of obesity-related gene mutations on HCC, we collected driver mutation genes in 34 TCGA patients with BMI ≥ 27 and 23 TCGA patients with BMI < 27. The digital PCR performing the PBMC samples for the variant rate by clinical cohort of 96 NAFLD patients. Our analysis showed that obesity leads to significantly worse survival outcomes in HCC. Using cbioportal, we identified 414 driver mutation genes in patients with obesity and 127 driver mutation genes in non-obese patients. Functional analysis showed that obese-related genes significantly enriched the regulated lipid and insulin pathways in HCC. The insulin secretion pathway in patients with obesity HCC-specific survival identified ABCC8 and PRKCB as significant genes (p < 0.001). It revealed significant differences in gene mutation and gene expression profiles compared to non-obese patients. The digital PCR test ABCC8 variants were detected in PBMC samples and caused a 14.5% variant rate, significantly higher than that of non-obese NAFLD patients. The study findings showed that the gene ABCC8 was a patient with the obesity-related gene in NAFLD, which provides the probability that ABCC8 mutation contributes to the pre-cancer lesion biomarker for HCC.

14.
Clin Gastroenterol Hepatol ; 22(3): 581-590.e6, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37871842

RESUMO

BACKGROUND & AIMS: Hepatitis B surface antigen (HBsAg) seroclearance is the goal of functional cure for hepatitis B virus (HBV) infection. However, the impact of metabolic dysfunction-associated steatotic liver disease (MASLD) on this favorable outcome remains unclear. METHODS: Patients with chronic hepatitis B (CHB) were consecutively recruited. MASLD was defined by the newly proposed disease criteria. Cumulative incidences and associated factors of HBsAg seroclearance/seroconversion were compared between the MASLD and non-MASLD groups. RESULTS: From 2006 to 2021, 4084 treatment-naive hepatitis B e antigen (HBeAg)-negative CHB patients were included. At baseline, CHB patients with concurrent MASLD (n = 887) had significantly lower levels of HBsAg and HBV DNA than the non-MASLD group (n = 3197). During a median follow-up of 5.0 years, MASLD was associated with a higher likelihood of HBsAg seroclearance (adjusted hazard ratio [aHR], 1.43; 95% confidence interval [CI], 1.10-1.85; P = .007), and the accumulation of individual metabolic dysfunctions additively facilitated HBsAg seroclearance. In addition, a higher rate of HBsAg seroconversion was observed in patients with MASLD versus those without MASLD (aHR, 1.37; 95% CI, 1.00-1.86; P = .049). In sensitivity analysis, patients with intermittent MASLD had an intermediate probability of HBsAg seroclearance. After balancing clinical and virologic profiles by inverse probability of treatment weighting (IPTW), MASLD was still associated with a higher HBsAg seroclearance rate (IPTW-adjusted HR, 1.41; 95% CI, 1.09-1.84; P = .010). CONCLUSIONS: In untreated HBeAg-negative CHB patients, concurrent MASLD is associated with higher rates of HBsAg seroclearance and seroconversion. Metabolic dysfunctions have additive effects on the functional cure of CHB.


Assuntos
Hepatite B Crônica , Hepatite B , Humanos , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Soroconversão , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , DNA Viral/análise , Hepatite B/tratamento farmacológico , Antivirais/uso terapêutico
15.
Artigo em Inglês | MEDLINE | ID: mdl-39181430

RESUMO

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) risk persists in patients with chronic hepatitis B (CHB) despite antiviral therapy. The relationship between pre-treatment baseline hepatitis B virus (HBV) viral load and HCC risk during antiviral treatment remains uncertain. METHODS: This multinational cohort study aimed to investigate the association between baseline HBV viral load and on-treatment HCC risk in 20,826 noncirrhotic, hepatitis B e antigen (HBeAg)-positive and HBeAg-negative patients with baseline HBV DNA levels ≥2000 IU/mL (3.30 log10 IU/mL) who initiated entecavir or tenofovir treatment. The primary outcome was on-treatment HCC incidence, stratified by baseline HBV viral load as a categorical variable. RESULTS: In total, 663 patients developed HCC over a median follow-up of 4.1 years, with an incidence rate of 0.81 per 100 person-years (95% confidence interval [CI], 0.75-0.87). Baseline HBV viral load was significantly associated with HCC risk in a non-linear parabolic pattern, independent of other factors. Patients with baseline viral load between 6.00 and 7.00 log10 IU/mL had the highest on-treatment HCC risk (adjusted hazard ratio, 4.28; 95% CI, 2.15-8.52; P < .0001) compared with those with baseline viral load ≥8.00 log10 IU/mL, who exhibited the lowest HCC risk. CONCLUSION: Baseline viral load showed a significant, non-linear, parabolic association with HCC risk during antiviral treatment in noncirrhotic patients with CHB. Early initiation of antiviral treatment based on HBV viral load may help prevent irreversible HCC risk accumulation in patients with CHB.

16.
Am J Gastroenterol ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38775310

RESUMO

INTRODUCTION: Concerns regarding bleeding remain in cold snare polypectomy (CSP) for small pedunculated (0-Ip) polyps. The aim of this study was to compare the risk of CSP and hot snare polypectomy (HSP) for such lesions. METHODS: Data on 0-Ip colorectal polyps ≤10 mm were extracted from a large, pragmatic, randomized trial. Immediate postpolypectomy bleeding (IPPB), defined as the perioperative use of a clip for bleeding, was evaluated through polyp-level analysis. Delayed postpolypectomy bleeding (DPPB), defined as bleeding occurring within 2 weeks postoperatively, was assessed at the patient-level among patients whose polyps were all ≤10 mm, including at least one 0-Ip polyp. RESULTS: A total of 647 0-Ip polyps (CSP: 306; HSP: 341) were included for IPPB analysis and 386 patients (CSP: 192; HSP: 194) for DPPB analysis. CSP was associated with a higher incidence of IPPB (10.8% vs 3.2%, P < 0.001) but no adverse clinical events. The procedure time of all polypectomies was shorter for CSP than for HSP (123.0 ± 117.8 vs 166.0 ± 237.7 seconds, P = 0.003), while the procedure time of polypectomies with IPPB were similar (249.8 ± 140.2 vs 227.4 ± 125.9 seconds, P = 0.64). DPPB was observed in 3 patients (1.5%) in the HSP group, including one patient (0.5%) with severe bleeding, but not in the CSP group. DISCUSSION: Despite CSP being associated with more IPPB events, it could be timely treated without adverse outcomes. Notably, no delayed bleeding occurred in the CSP group. Our findings support the use of CSP for 0-Ip polyps ≤ 10 mm.

17.
Small ; : e2405822, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39101605

RESUMO

Prussian blue analogs (PBAs) show promise as cathodes for sodium-ion batteries due to their notable cycle stability, cost-effectiveness, and eco-friendly nature, yet the presence of interstitial water limits the specific capacity and obstructs Na+ mobility within the material. Although considerable experimental efforts are focused on dehydrating water for capacity enhancement, there is still a deficiency of a comprehensive understanding of the low capacity of low-spin Fe resulting from interstitial water, which holds significance in Na+ storage. This study introduces a novel gas-assisted heat treatment method to efficiently remove interstitial water from Fe-based PBA (NaFeHCF) electrodes and combines experiments and theoretical calculations to reveal the iron spin state regulation that is related to the capacity enhancement mechanism. This dehydration strategy significantly enhances battery capacity, especially the portion at higher voltages (3.4-4.0 V). The increase in capacity is attributed to the following factors: an enhanced proportion of Fe2+, reduced water content which facilitates faster charge transfer, and the activation of low spin Fe2+. The optimized NaFeHCF demonstrated impressive half-cell performance of retaining 87.3% capacity after 2000 cycles at a 5 C rate and achieving 100 mAh g-1 capacity over 200 cycles when being paired with hard carbon, exhibiting its practical potential.

18.
Small ; 20(22): e2309181, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38100297

RESUMO

The development of catalysts with abundant active interfaces for superior low-temperature catalytic CO oxidation is critical to meet increasingly rigorous emission requirements, yet still challenging. Herein, this work reports a PtCo/CoOx/Al2O3 catalyst with PtCo clusters and enriched Pt─O─Co interfaces induced by hydrogen spillover from the Pt sites and self-oxidation process in air, exhibiting excellent performance for CO oxidation at low temperatures and humid conditions. The combination of structural characterizations and in situ Fourier transform infrared spectroscopy reveals that the PtCo cluster effectively prevents CO saturation/poisoning on the Pt surface. Additionally, the presence of Pt─O─Co interfaces in the PtCo/CoOx/Al2O3 catalyst provides a significant number of active sites for oxygen activation and ─OH formation. This facilitates efficient generation of CO2 at ambient temperature by coupling with nearby adsorbed CO molecules, resulting in superior low-temperature activity and long-term stability for CO oxidation under humid conditions. This work provides a facile route toward rationalizing the design of catalysts with more active interfaces for superior low-temperature CO oxidation under humid conditions for practical applications.

19.
Small ; 20(31): e2311151, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38456785

RESUMO

As vitally prospective candidates for next-generation energy storage systems, room-temperature sodium-sulfur (RT-Na/S) batteries continue to face obstacles in practical implementation due to the severe shuttle effect of sodium polysulfides and sluggish S conversion kinetics. Herein, the study proposes a novel approach involving the design of a B, N co-doped carbon nanotube loaded with highly dispersed and electron-deficient cobalt (Co@BNC) as a highly conductive host for S, aiming to enhance adsorption and catalyze redox reactions. Crucially, the pivotal roles of the carbon substrate in prompting the electrocatalytic activity of Co are elucidated. The experiments and density functional theory (DFT) calculations both demonstrate that after B doping, stronger chemical adsorption toward polysulfides (NaPSs), lower polarization, faster S conversion kinetics, and more complete S transformation are achieved. Therefore, the as-assembled RT-Na/S batteries with S/Co@BNC deliver a high reversible capacity of 626 mAh g-1 over 100 cycles at 0.1 C and excellent durability (416 mAh g-1 over 600 cycles at 0.5 C). Even at 2 C, the capacity retention remains at 61.8%, exhibiting an outstanding rate performance. This work offers a systematic way to develop a novel Co electrocatalyst for RT-Na/S batteries, which can also be effectively applied to other transition metallic electrocatalysts.

20.
J Med Virol ; 96(5): e29675, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38746997

RESUMO

Early confirmation of sustained virologic response (SVR) or viral relapse after direct-acting antivirals (DAAs) for hepatitis C virus (HCV) infection is essential based on public health perspectives, particularly for patients with high risk of nonadherence to posttreatment follow-ups. A total of 1011 patients who achieved end-of-treatment virologic response, including 526 receiving fixed-dose pangenotypic DAAs, and 485 receiving other types of DAAs, who had available off-treatment weeks 4 and 12 serum HCV RNA data to confirm SVR at off-treatment week 12 (SVR12) or viral relapse were included. The positive predictive value (PPV) and negative predictive value (NPV) of SVR4 to predict patients with SVR12 or viral relapse were reported. Furthermore, we analyzed the proportion of concordance between SVR12 and SVR24 in 943 patients with available SVR24 data. The PPV and NPV of SVR4 to predict SVR12 were 98.5% (95% confidence interval [CI]: 98.0-98.9) and 100% (95% CI: 66.4-100) in the entire population. The PPV of SVR4 to predict SVR12 in patients receiving fixed-dose pangenotypic DAAs was higher than those receiving other types of DAAs (99.8% [95% CI: 98.9-100] vs. 97.1% [95% CI: 96.2-97.8], p < 0.001). The NPVs of SVR4 to predict viral relapse were 100%, regardless of the type of DAAs. Moreover, the concordance between SVR12 and SVR24 was 100%. In conclusion, an off-treatment week 4 serum HCV RNA testing is sufficient to provide an excellent prediction power of SVR or viral relapse at off-treatment week 12 among patients with HCV who are treated with fixed-dose pangenotypic DAAs.


Assuntos
Antivirais , Hepacivirus , Hepatite C Crônica , RNA Viral , Resposta Viral Sustentada , Humanos , Antivirais/uso terapêutico , Antivirais/administração & dosagem , Masculino , Feminino , Pessoa de Meia-Idade , Hepacivirus/genética , Hepacivirus/efeitos dos fármacos , Idoso , Adulto , RNA Viral/sangue , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Recidiva , Seguimentos , Resultado do Tratamento , Hepatite C/tratamento farmacológico , Hepatite C/virologia
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