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1.
Mol Cell ; 81(21): 4467-4480.e7, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34687604

RESUMO

Viral RNA-dependent RNA polymerases (RdRps) are a target for broad-spectrum antiviral therapeutic agents. Recently, we demonstrated that incorporation of the T-1106 triphosphate, a pyrazine-carboxamide ribonucleotide, into nascent RNA increases pausing and backtracking by the poliovirus RdRp. Here, by monitoring enterovirus A-71 RdRp dynamics during RNA synthesis using magnetic tweezers, we identify the "backtracked" state as an intermediate used by the RdRp for copy-back RNA synthesis and homologous recombination. Cell-based assays and RNA sequencing (RNA-seq) experiments further demonstrate that the pyrazine-carboxamide ribonucleotide stimulates these processes during infection. These results suggest that pyrazine-carboxamide ribonucleotides do not induce lethal mutagenesis or chain termination but function by promoting template switching and formation of defective viral genomes. We conclude that RdRp-catalyzed intra- and intermolecular template switching can be induced by pyrazine-carboxamide ribonucleotides, defining an additional mechanistic class of antiviral ribonucleotides with potential for broad-spectrum activity.


Assuntos
Pirazinas/química , Vírus de RNA/genética , RNA Viral/genética , RNA Polimerase Dependente de RNA/genética , Recombinação Genética , Ribonucleotídeos/química , Animais , Antivirais , Catálise , Células Cultivadas , Técnicas Genéticas , Genoma , Genoma Viral , Recombinação Homóloga , Humanos , Cinética , Camundongos , Camundongos Transgênicos , Simulação de Dinâmica Molecular , Mutagênese , Nucleotídeos/genética , Conformação Proteica , RNA/química , RNA Polimerase Dependente de RNA/metabolismo , RNA-Seq , Transgenes , Virulência
2.
Proc Natl Acad Sci U S A ; 121(6): e2309627121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38294940

RESUMO

We present an accreditation protocol for analogue, i.e., continuous-time, quantum simulators. For a given simulation task, it provides an upper bound on the variation distance between the probability distributions at the output of an erroneous and error-free analogue quantum simulator. As its overheads are independent of the size and nature of the simulation, the protocol is ready for immediate usage and practical for the long term. It builds on the recent theoretical advances of strongly universal Hamiltonians and quantum accreditation as well as experimental progress toward the realization of programmable hybrid analogue-digital quantum simulators.

3.
Proc Natl Acad Sci U S A ; 120(35): e2307625120, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37603751

RESUMO

Trehalose plays a crucial role in the survival and virulence of the deadly human pathogen Mycobacterium tuberculosis (Mtb). The type I ATP-binding cassette (ABC) transporter LpqY-SugABC is the sole pathway for trehalose to enter Mtb. The substrate-binding protein, LpqY, which forms a stable complex with the translocator SugABC, recognizes and captures trehalose and its analogues in the periplasmic space, but the precise molecular mechanism for this process is still not well understood. This study reports a 3.02-Å cryoelectron microscopy structure of trehalose-bound Mtb LpqY-SugABC in the pretranslocation state, a crystal structure of Mtb LpqY in a closed form with trehalose bound and five crystal structures of Mtb LpqY in complex with different trehalose analogues. These structures, accompanied by substrate-stimulated ATPase activity data, reveal how LpqY recognizes and binds trehalose and its analogues, and highlight the flexibility in the substrate binding pocket of LpqY. These data provide critical insights into the design of trehalose analogues that could serve as potential molecular probe tools or as anti-TB drugs.


Assuntos
Mycobacterium tuberculosis , Humanos , Microscopia Crioeletrônica , Trealose , Transportadores de Cassetes de Ligação de ATP , Sondas Moleculares
4.
J Biol Chem ; 300(6): 107361, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38735473

RESUMO

Nucleoside analogue drugs are pervasively used as antiviral and chemotherapy agents. Cytarabine and gemcitabine are anti-cancer nucleoside analogue drugs that contain C2' modifications on the sugar ring. Despite carrying all the required functional groups for DNA synthesis, these two compounds inhibit DNA extension once incorporated into DNA. It remains unclear how the C2' modifications on cytarabine and gemcitabine affect the polymerase active site during substrate binding and DNA extension. Using steady-state kinetics, static and time-resolved X-ray crystallography with DNA polymerase η (Pol η) as a model system, we showed that the sugar ring C2' chemical groups on cytarabine and gemcitabine snugly fit within the Pol η active site without occluding the steric gate. During DNA extension, Pol η can extend past gemcitabine but with much lower efficiency past cytarabine. The Pol η crystal structures show that the -OH modification in the ß direction on cytarabine locks the sugar ring in an unfavorable C2'-endo geometry for product formation. On the other hand, the addition of fluorine atoms on gemcitabine alters the proper conformational transition of the sugar ring for DNA synthesis. Our study illustrates mechanistic insights into chemotherapeutic drug inhibition and resistance and guides future optimization of nucleoside analogue drugs.


Assuntos
Citarabina , DNA Polimerase Dirigida por DNA , Desoxicitidina , Gencitabina , Desoxicitidina/análogos & derivados , Desoxicitidina/química , Desoxicitidina/farmacologia , Citarabina/química , Citarabina/farmacologia , DNA Polimerase Dirigida por DNA/metabolismo , DNA Polimerase Dirigida por DNA/química , Humanos , Cristalografia por Raios X , DNA/química , DNA/metabolismo , DNA/biossíntese , Domínio Catalítico , Replicação do DNA/efeitos dos fármacos , Cinética
5.
J Cell Sci ; 136(3)2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36620935

RESUMO

High expression of the non-receptor tyrosine kinase FER is an independent prognostic factor that correlates with poor survival in breast cancer patients. To investigate whether the kinase activity of FER is essential for its oncogenic properties, we developed an ATP analogue-sensitive knock-in allele (FERASKI). Specific FER kinase inhibition in MDA-MB-231 cells reduces migration and invasion, as well as metastasis when xenografted into a mouse model of breast cancer. Using the FERASKI system, we identified Ski family transcriptional corepressor 1 (SKOR1) as a direct FER kinase substrate. SKOR1 loss phenocopies FER inhibition, leading to impaired proliferation, migration and invasion, and inhibition of breast cancer growth and metastasis formation in mice. We show that SKOR1 Y234, a candidate FER phosphorylation site, is essential for FER-dependent tumor progression. Finally, our work suggests that the SKOR1 Y234 residue promotes Smad2/3 signaling through SKOR1 binding to Smad3. Our study thus identifies SKOR1 as a mediator of FER-dependent progression of high-risk breast cancers.


Assuntos
Neoplasias , Proteínas Tirosina Quinases , Animais , Camundongos , Proteínas Tirosina Quinases/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Fosforilação , Transdução de Sinais , Neoplasias/metabolismo
6.
J Pathol ; 263(4-5): 403-417, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38886898

RESUMO

The evolution of cancer treatment has provided increasingly targeted strategies both in the upfront and relapsed disease settings. Small-molecule inhibitors and immunotherapy have risen to prominence with chimeric antigen receptor T-cells, checkpoint inhibitors, kinase inhibitors, and monoclonal antibody therapies being deployed across a range of solid organ and haematological malignancies. However, novel approaches are required to target transcription factors and oncogenic fusion proteins that are central to cancer biology and have generally eluded successful drug development. Thalidomide analogues causing protein degradation have been a cornerstone of treatment in multiple myeloma, but a lack of in-depth mechanistic understanding initially limited progress in the field. When the protein cereblon (CRBN) was found to mediate thalidomide analogues' action and CRBN's neo-targets were identified, existing and novel drug development accelerated, with applications outside multiple myeloma, including non-Hodgkin's lymphoma, myelodysplastic syndrome, and acute leukaemias. Critically, transcription factors were the first canonical targets described. In addition to broadening the application of protein-degrading drugs, resistance mechanisms are being overcome and targeted protein degradation is widening the scope of druggable proteins against which existing approaches have been ineffective. Examples of targeted protein degraders include molecular glues and proteolysis targeting chimeras (PROTACs): heterobifunctional molecules that bind to proteins of interest and cause proximity-induced ubiquitination and proteasomal degradation via a linked E3 ligase. Twenty years since their inception, PROTACs have begun progressing through clinical trials, with early success in targeting the oestrogen receptor and androgen receptor in breast and prostate cancer respectively. This review explores important developments in targeted protein degradation to both treat and study cancer. It also considers the potential advantages and challenges in the translational aspects of developing new treatments. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Neoplasias , Proteólise , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Ubiquitina-Proteína Ligases/metabolismo , Terapia de Alvo Molecular , Animais
7.
Nano Lett ; 24(3): 866-872, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38205713

RESUMO

A critical bottleneck for the training of large neural networks (NNs) is communication with off-chip memory. A promising mitigation effort consists of integrating crossbar arrays of analogue memories in the Back-End-Of-Line, to store the NN parameters and efficiently perform the required synaptic operations. The "Tiki-Taka" algorithm was developed to facilitate NN training in the presence of device nonidealities. However, so far, a resistive switching device exhibiting all the fundamental Tiki-Taka requirements, which are many programmable states, a centered symmetry point, and low programming noise, was not yet demonstrated. Here, a complementary metal-oxide semiconductor (CMOS)-compatible resistive random access memory (RRAM), showing more than 30 programmable states with low noise and a symmetry point with only 5% skew from the center, is presented for the first time. These results enable generalization of Tiki-Taka training from small fully connected networks to larger long-/short-term-memory types of NN.

8.
Nano Lett ; 24(22): 6658-6664, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38770882

RESUMO

Synthetic quantum systems provide a pathway for exploring the physics of complex quantum matter in a programmable fashion. This approach becomes particularly advantageous when it comes to systems that are thermodynamically unfavorable. By sculpting the potential landscape of Cu(111) surfaces with carbon monoxide quantum corrals in a cryogenic scanning tunneling microscope, we created analogue simulators of planar organic molecules, including antiaromatic and non-Kekulé species that are generally reactive or unstable. Spectroscopic imaging of such synthetic molecules reveals close replications of molecular orbitals obtained from ab initio calculations of the organic molecules. We further illustrate the quantitative nature of such analogue simulators by faithful extraction of bond orders and global aromaticity indices, which are otherwise technically daunting using real molecules. Our approach therefore sets the stage for new research frontiers pertaining to the quantum physics and chemistry of designer nanostructures.

9.
Diabetologia ; 67(9): 1783-1799, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38985162

RESUMO

AIMS/HYPOTHESIS: The aim of this study was to evaluate the efficacy and safety of oral semaglutide monotherapy vs placebo in a predominantly Chinese population with type 2 diabetes insufficiently controlled with diet and exercise alone. METHODS: The Peptide Innovation for Early Diabetes Treatment (PIONEER) 11 trial was a double-blind, randomised, Phase IIIa trial conducted across 52 sites in the China region (mainland China and Taiwan), Hungary, Serbia and Ukraine. Eligible participants were ≥18 years (≥20 years in Taiwan), had a diagnosis of type 2 diabetes with HbA1c 53-86 mmol/mol (7.0-10.0%) and were not receiving any glucose-lowering drugs. After a 4-week run-in period in which participants were treated with diet and exercise alone, those who fulfilled the randomisation criteria were randomised (1:1:1:1) using a web-based randomisation system to receive once-daily oral semaglutide 3 mg, 7 mg or 14 mg or placebo for 26 weeks (using a 4-week dose-escalation regimen for the higher doses). Randomisation was stratified according to whether participants were from the China region or elsewhere. The primary and confirmatory secondary endpoints were change from baseline to week 26 in HbA1c and body weight (kg), respectively. Safety was assessed in all participants exposed to at least one dose of the trial product. RESULTS: Between October 2019 and October 2021, a total of 774 participants were screened and 521 participants were randomised to oral semaglutide 3 mg (n=130), 7 mg (n=130), 14 mg (n=130) or placebo (n=131); most participants (92.5%, n=482) completed the trial, with 39 participants prematurely discontinuing treatment. The number of participants contributing to the trial analyses was based on the total number of participants who were randomised at the beginning of the trial. The majority of participants were male (63.7%), and the mean age of participants was 52 years. At baseline, mean HbA1c and body weight were 63 mmol/mol (8.0%) and 79.6 kg, respectively. Oral semaglutide resulted in significantly greater reductions in HbA1c than placebo at week 26 (p<0.001 for all doses). The estimated treatment differences (ETDs [95% CIs]) for oral semaglutide 3 mg, 7 mg and 14 mg vs placebo were -11 (-13, -9) mmol/mol, -16 (-18, -13) mmol/mol and -17 (-19, -15) mmol/mol, respectively. The corresponding ETDs in percentage points (95% CI) vs placebo were -1.0 (-1.2, -0.8), -1.4 (-1.6, -1.2) and -1.5 (-1.8, -1.3), respectively. Significantly greater reductions in body weight were also observed for oral semaglutide 7 mg and 14 mg than for placebo at week 26 (ETD [95% CI] -1.2 kg [-2.0 kg, -0.4 kg; p<0.01] and -2.0 kg [-2.8 kg, -1.2 kg; p<0.001], respectively), but not for oral semaglutide 3 mg (ETD [95% CI] -0.0 kg [-0.9 kg, 0.8 kg; not significant]). Similar reductions in HbA1c and body weight were observed in the Chinese subpopulation, which represented 74.9% of participants in the overall population. Adverse events (AEs) occurred in between 65.4% and 72.3% of participants receiving oral semaglutide (for all doses) and 57.3% of participants with placebo. Most AEs were mild to moderate in severity, with few serious AEs reported; the most commonly reported AEs were gastrointestinal-related and were more frequent with semaglutide (all doses) than with placebo. The proportion of AEs was slightly higher in the Chinese subpopulation. CONCLUSIONS/INTERPRETATION: Oral semaglutide resulted in significantly greater reductions in HbA1c across all doses and in significant body weight reductions for the 7 mg and 14 mg doses when compared with placebo in predominantly Chinese participants with type 2 diabetes insufficiently controlled by diet and exercise alone. Oral semaglutide was generally well tolerated, with a safety profile consistent with that seen in the global PIONEER trials. TRIAL REGISTRATION: ClinicalTrials.gov NCT04109547. FUNDING: Novo Nordisk A/S.


Assuntos
Diabetes Mellitus Tipo 2 , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon , Hipoglicemiantes , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Administração Oral , Povo Asiático , Glicemia/efeitos dos fármacos , China , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , População do Leste Asiático , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Hemoglobinas Glicadas/metabolismo , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Resultado do Tratamento , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon/efeitos adversos , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon/uso terapêutico
10.
Diabetologia ; 67(9): 1800-1816, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38985161

RESUMO

AIMS/HYPOTHESIS: The aim of this study was to assess the efficacy and safety of oral semaglutide vs sitagliptin in a predominantly Chinese population with type 2 diabetes inadequately controlled with metformin treatment. METHODS: The Peptide Innovation for Early Diabetes Treatment (PIONEER) 12 trial was a randomised, double-dummy, active-controlled, parallel-group, Phase IIIa trial conducted over 26 weeks at 90 sites across the China region (including mainland China, Taiwan and Hong Kong) and five other countries. Adults aged ≥18 years (≥20 years in Taiwan) with a diagnosis of type 2 diabetes, HbA1c between 53 and 91 mmol/mol (inclusive) and treated with a stable daily dose of metformin were eligible for inclusion. Participants were randomised (1:1:1:1) using a web-based randomisation system to either once-daily oral semaglutide (3 mg, 7 mg or 14 mg) or once-daily oral sitagliptin 100 mg. Treatment allocation was masked to both participants and investigators. Randomisation was stratified according to whether participants were from the China region or elsewhere. The primary endpoint was change in HbA1c from baseline to week 26. The confirmatory secondary endpoint was change in body weight (kg) from baseline to week 26. All randomised participants were included in the full analysis set (FAS). All participants exposed to at least one dose of trial product were included in the safety analysis (SAS). RESULTS: Of 1839 participants screened, 1441 were randomly assigned to oral semaglutide 3 mg (n=361), 7 mg (n=360), 14 mg (n=361) or sitagliptin 100 mg (n=359) and included in the FAS. A total of 1438 participants were included in the SAS. In total, 75.2% of participants were from the China region. A total of 1372 (95.2%) participants completed the trial and 130 participants prematurely discontinued treatment (8.3%, 8.6% and 15.0% for oral semaglutide 3 mg, 7 mg and 14 mg, respectively; 4.2% for sitagliptin 100 mg). Significantly greater reductions in HbA1c from baseline to week 26 were reported for all doses of oral semaglutide vs sitagliptin 100 mg. For oral semaglutide 3 mg, 7 mg and 14 mg vs sitagliptin 100 mg, the estimated treatment differences (ETDs [95% CI]) were -2 (-4, -1) mmol/mol, -8 (-9, -6) mmol/mol and -11 (-12, -9) mmol/mol, respectively. The corresponding ETDs (95% CI) in percentage points vs sitagliptin 100 mg were -0.2 (-0.3, -0.1), -0.7 (-0.8, -0.6) and -1.0 (-1.1, -0.8), respectively. Reductions in body weight were significantly greater for all doses of oral semaglutide vs sitagliptin 100 mg (ETD [95% CI] -0.9 [-1.4, -0.4] kg, -2.3 [-2.8, -1.8] kg and -3.3 [-3.8, -2.8] kg for 3 mg, 7 mg and 14 mg, respectively). In the subpopulation of participants from the China region (75.2% of trial participants), reductions in HbA1c and body weight from baseline to week 26 were similar to those seen in the overall population. The most frequent adverse events in the semaglutide treatment arms were gastrointestinal, although these were mostly transient and mild/moderate in severity. CONCLUSIONS/INTERPRETATION: Significantly greater reductions in both HbA1c and body weight over 26 weeks were seen with oral semaglutide 3 mg, 7 mg and 14 mg than with sitagliptin 100 mg in a predominantly Chinese population with type 2 diabetes inadequately controlled with metformin treatment. Oral semaglutide was generally well tolerated, with a safety profile consistent with that seen in the global PIONEER trials. TRIAL REGISTRATION: ClinicalTrials.gov NCT04017832. FUNDING: This trial was funded by Novo Nordisk A/S, Søborg, Denmark.


Assuntos
Diabetes Mellitus Tipo 2 , Peptídeos Semelhantes ao Glucagon , Hipoglicemiantes , Metformina , Fosfato de Sitagliptina , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Administração Oral , Povo Asiático , Glicemia/efeitos dos fármacos , China , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , População do Leste Asiático , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Hemoglobinas Glicadas/metabolismo , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Metformina/uso terapêutico , Metformina/administração & dosagem , Fosfato de Sitagliptina/uso terapêutico , Fosfato de Sitagliptina/efeitos adversos , Fosfato de Sitagliptina/administração & dosagem , Resultado do Tratamento , Triazóis/uso terapêutico , Triazóis/efeitos adversos , Triazóis/administração & dosagem
11.
Plant J ; 116(5): 1355-1369, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37647363

RESUMO

2,4-dichlorophenoxyacetic acid (2,4-D) is a synthetic analogue of the plant hormone auxin that is commonly used in many in vitro plant regeneration systems, such as somatic embryogenesis (SE). Its effectiveness in inducing SE, compared to the natural auxin indole-3-acetic acid (IAA), has been attributed to the stress triggered by this compound rather than its auxinic activity. However, this hypothesis has never been thoroughly tested. Here we used a library of forty 2,4-D analogues to test the structure-activity relationship with respect to the capacity to induce SE and auxinic activity in Arabidopsis thaliana. Four analogues induced SE as effectively as 2,4-D and 13 analogues induced SE but were less effective. Based on root growth inhibition and auxin response reporter expression, the 2,4-D analogues were classified into different groups, ranging from very active to not active auxin analogues. A halogen at the 4-position of the aromatic ring was important for auxinic activity, whereas a halogen at the 3-position resulted in reduced activity. Moreover, a small substitution at the carboxylate chain was tolerated, as was extending the carboxylate chain with an even number of carbons. The auxinic activity of most 2,4-D analogues was consistent with their simulated TIR1-Aux/IAA coreceptor binding characteristics. A strong correlation was observed between SE induction efficiency and auxinic activity, which is in line with our observation that 2,4-D-induced SE and stress both require TIR1/AFB auxin co-receptor function. Our data indicate that the stress-related effects triggered by 2,4-D and considered important for SE induction are downstream of auxin signalling.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Ácido 2,4-Diclorofenoxiacético/farmacologia , Ácido 2,4-Diclorofenoxiacético/metabolismo , Relação Estrutura-Atividade , Halogênios/metabolismo , Halogênios/farmacologia , Regulação da Expressão Gênica de Plantas
12.
J Hepatol ; 81(2): 218-226, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38527527

RESUMO

BACKGROUND & AIMS: Factors predicting HBsAg seroclearance after treatment cessation, irrespective of nucleos(t)ide analogue (NA) resumption, have important clinical implications. We evaluated predictors of long-term HBsAg seroclearance after entecavir cessation. METHODS: This study followed-up Chinese patients with chronic hepatitis B from two previous studies of entecavir cessation. All patients were non-cirrhotic, HBeAg-negative, with undetectable HBV DNA (<20 IU/ml) at end-of-treatment (EOT). They were monitored closely for 48 weeks with regular HBV DNA, quantitative HBsAg (qHBsAg) and alanine aminotransferase (ALT) measurements. Entecavir was resumed at HBV DNA >2,000 IU/ml, irrespective of ALT levels. After the initial 48 weeks, patients were assessed every 6 months, regardless of entecavir resumption, to monitor for HBsAg seroclearance. RESULTS: A total of 194 patients (63.4% male, mean age 49.9 years, on entecavir for a median of 47.2 months) were recruited; 94 (48.5%) and 158 (81.4%) patients had EOT qHBsAg <100 IU/ml and <1,000 IU/ml, respectively; 151 (77.8%) patients were eventually resumed on entecavir. After follow-up for a median of 70.7 (51.0-118.2) months, 28 (14.4%) patients had HBsAg seroclearance. qHBsAg levels at weeks 36 and 48 after EOT independently predicted HBsAg seroclearance (both p <0.01), whereas qHBsAg from EOT to week 24 only trended towards statistical significance. The ratio of ALT/qHBsAg at all time points from EOT to week 48 independently predicted HBsAg seroclearance (hazard ratios ranging from 1.003-1.028, all p <0.01) with excellent diagnostic performance (area under the receiver-operating characteristic curve 0.799-0.933, negative predictive value >90% at different time points), regardless of whether entecavir was resumed. CONCLUSIONS: The ALT/qHBsAg ratio after entecavir cessation predicts HBsAg seroclearance, even in patients who were resumed on treatment. Its use may mitigate the risk of severe hepatitis flares in patients managed by observation without treatment resumption. IMPACT AND IMPLICATIONS: Current predictors of HBsAg seroclearance after finite nucleos(t)ide analogue (NA) therapy have suboptimal predictive value. We demonstrated that the ALT/qHBsAg ratio may be able to reflect the balance between host control and virological activity. The ALT/qHBsAg ratio at different time points from end-of-treatment till week 48 independently and accurately predicted HBsAg seroclearance in patients who have stopped entecavir. The ALT/qHBsAg ratio may be utilized by clinicians for patient selection and retreatment decisions in finite NA therapy.


Assuntos
Alanina Transaminase , Antivirais , Guanina , Antígenos de Superfície da Hepatite B , Hepatite B Crônica , Humanos , Guanina/análogos & derivados , Guanina/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Hepatite B Crônica/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Antivirais/uso terapêutico , Alanina Transaminase/sangue , Antígenos de Superfície da Hepatite B/sangue , Adulto , DNA Viral/sangue , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/efeitos dos fármacos , China , Seguimentos , População do Leste Asiático
13.
Artigo em Inglês | MEDLINE | ID: mdl-39089518

RESUMO

BACKGROUND AND AIMS: Whether tenofovir or entecavir has different effects on the prevention of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) in secondary and tertiary preventive settings is still a matter of debate. This study aimed to compare the long-term prognosis of HCC between tenofovir and entecavir in patients with chronic hepatitis B. METHODS: Chronic hepatitis B patients diagnosed with HCC between November 2008 and December 2018 and treated with either entecavir or tenofovir at a tertiary center in Korea were included. The effect of tenofovir compared with entecavir on the prognosis of HBV-related HCC was assessed using multivariable-adjusted Cox and propensity score (PS)-matched analyses. Various predefined subgroup analyses were conducted. RESULTS: During a median follow-up period of 3.0 years, the mortality rate for entecavir-treated patients (n = 3469) was 41.2%, while tenofovir-treated patients (n = 3056) had a mortality rate of 34.6%. Overall survival (OS) was better in the tenofovir group (adjusted hazard ratio [aHR], 0.79; P < .001), which were consistently observed in the PS-matched analysis. The magnitude of the risk difference in OS was more prominent 2 years after the diagnosis of HCC (aHR, 0.50; P < .001) than 2 years before (aHR, 0.88; P = .005), and it was more pronounced in patients with earlier HCC stages. In all subgroups, except for those with shorter life expectancy, such as those with compromised liver function, tenofovir was associated with better OS compared with entecavir. CONCLUSIONS: Among patients with HBV-related HCC, those treated with tenofovir had a better prognosis than those treated with entecavir, particularly among those with prolonged survival.

14.
Clin Gastroenterol Hepatol ; 22(3): 532-541.e8, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37924855

RESUMO

BACKGROUND: Although both nonsteroidal anti-inflammatory drugs (NSAIDs) and opioids are used for analgesia in acute pancreatitis (AP), the analgesic of choice is not known. We compared buprenorphine, an opioid, and diclofenac, an NSAID, for analgesia in AP. METHODS: In a double-blind randomized controlled trial, AP patients were randomized to receive intravenous diclofenac or intravenous buprenorphine. Fentanyl was used as rescue analgesia, delivered through a patient-controlled analgesia pump. Primary outcome was the difference in the dose of rescue fentanyl required. Secondary outcomes were the number of effective and ineffective demands of rescue fentanyl, pain-free interval, reduction in visual analogue scale (VAS) score, adverse events, and organ failure development. RESULTS: Twenty-four patients were randomized to diclofenac and 24 to buprenorphine. The 2 groups were matched at baseline. The total amount of rescue fentanyl required was significantly lower in the buprenorphine group:130 µg, interquartile range (IQR), 80-255 vs 520 µg, IQR, 380-1065 (P < .001). The number of total demands was 32 (IQR, 21-69) in the diclofenac arm vs 8 (IQR, 4-15) in the buprenorphine arm (P < .001). The buprenorphine group had more prolonged pain-free interval (20 vs 4 hours; P < .001), with greater reduction in the VAS score at 24, 48, and 72 hours compared with the diclofenac group. These findings were confirmed in the subgroup of moderately severe/severe pancreatitis. Adverse events profile was similar in the 2 groups. CONCLUSIONS: Compared with diclofenac, buprenorphine appears to be more effective and equally safe for pain management in AP patients, even in the subcohort of moderately severe or severe pancreatitis (Trial Registration number: CTRI/2020/07/026914).


Assuntos
Buprenorfina , Pancreatite , Humanos , Diclofenaco/efeitos adversos , Buprenorfina/efeitos adversos , Manejo da Dor , Doença Aguda , Pancreatite/complicações , Pancreatite/tratamento farmacológico , Pancreatite/induzido quimicamente , Anti-Inflamatórios não Esteroides/efeitos adversos , Analgésicos Opioides/uso terapêutico , Dor/etiologia , Dor/induzido quimicamente , Fentanila/efeitos adversos , Método Duplo-Cego
15.
Small ; : e2406369, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39319487

RESUMO

MXenes exhibit a unique combination of properties-2D structure, high conductivity, exceptional capacity, and chemical resistance-making them promising candidates for hybrid supercapacitors (HSCs). However, the development of MXene-based HSCs is often hindered by the limited availability of cathode materials that deliver comparable electrochemical performance, especially in protic electrolytes. In this study, this challenge is addressed by introducing a durable protic HSC utilizing a bimetallic Prussian Blue Analogue (PBA) decorated on reduced graphene oxide (rGO) as a nanocomposite cathode paired with a single-layered Ti3C2Tx MXene (SL-MXene) anode. The bimetallic PBA, specifically nickel hexacyanocobaltate (NiHCC), is utilized by virtue of its open and stable structure that facilitates efficient charge storage, leading to enhanced stability and energy storage capabilities. The resulting NiHCC/rGO//SL-MXene cell demonstrates impressive performance, achieving a maximum specific energy of 38.03 Wh kg-1 and a power density of 20 666.67 W kg-1. Remarkably, the NiHCC/rGO//SL-MXene HSC cell also exhibits excellent cycling stability without any loss even after 15 000 cycles while retaining ≈100% coulombic efficiency. This work underscores the potential of bimetallic PBA materials with conductive rGO backbone for overcoming the limitations of current MXene-based protic HSCs, highlighting the significance of this work.

16.
Small ; 20(33): e2311267, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38534041

RESUMO

The controllable construction of complex metal-organic coordination polymers (CPs) merits untold scientific and technological potential, yet remains a grand challenge of one-step construction and modulating simultaneously valence states of metals and topological morphology. Here, a thiocyanuric acid (TCA)-triggered strategy is presented to one-step rapid synthesis a double-crystalline Prussian blue analogue hetero-superstructure (PBA-hs) that comprises a Co3[Fe(CN)6]2 cube overcoated with a KCo[Fe(CN)6] shell, followed by eight self-assembled small cubes on vertices. Unlike common directing surfactants, TCA not only acts as a trigger for the fast growth of KCo[Fe(CN)6] on the Co3[Fe(CN)6]2 phase resulting in a PBA-on-PBA hetero-superstructure, but also serves as a flange-like bridge between them. By combining experiments with simulations, a deprotonation-induced electron transfer (DIET) mechanism is proposed for formation of second phase in PBA-hs, differing from thermally and photo-induced electron transfer processes. To prove utility, the calcined PBA-hs exhibits enhanced oxygen evolution reaction performance. This work provides a new method to design of novel CPs for enriching chemistry and material science. This work offers a practical approach to design novel CPs for enriching chemistry and material science.

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.
Clin Endocrinol (Oxf) ; 100(4): 368-378, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38300440

RESUMO

OBJECTIVE: Serum luteinising hormone (LH) concentration has been reported to be lower in girls with overweight and obesity (OW/OB) as compared with girls with normal weight (NW). This study aimed to evaluate peak serum LH concentration during gonadotropin-releasing hormone analogue (GnRHa) test in girls with OW/OB and NW who had central precocious puberty (CPP) and to determine peak serum LH cut-off for diagnosing CPP in girls with OW/OB. DESIGN, PATIENTS AND MEASUREMENTS: Medical records of 971 girls with premature breast development who underwent subcutaneous GnRHa (100 µg of triptorelin acetate) test were reviewed. All girls were classified as either CPP or premature thelarche. All of them were further classified into two groups according to their body mass index as NW and OW/OB groups for each Tanner stage. RESULTS: There were 634 and 337 girls in NW and OW/OB groups, respectively. CPP was diagnosed in 600 girls (249 had Tanner stage II and 351 had Tanner stage III). There were no differences in peak serum LH concentrations between CPP girls with NW and OW/OB. Peak serum LH cut-off of 5 IU/L (the current widely used cut-off) had a sensitivity and a specificity of 75% and 90%, respectively in NW group. Peak serum LH cut-off for CPP diagnosis was lower at 4 IU/L in the OW/OB group with greater sensitivity and specificity of 86% and 93%, respectively. The results were reproducible for each Tanner stage of breasts. CONCLUSION: Lower peak serum LH cut-off to 4 IU/L for diagnosing CPP in girls with OW/OB should be considered to avoid underdiagnosis of the condition.


Assuntos
Puberdade Precoce , Feminino , Humanos , Puberdade Precoce/diagnóstico , Hormônio Liberador de Gonadotropina , Hormônio Luteinizante , Pamoato de Triptorrelina , Obesidade/diagnóstico , Sobrepeso/diagnóstico , Hormônio Foliculoestimulante
19.
Cardiovasc Diabetol ; 23(1): 352, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39342203

RESUMO

AIMS: To estimate the incidence of major adverse cardiovascular events (MACE), expanded MACE, and MACE or Death across Fibrosis- 4 score (FIB-4) categories in people with type 2 diabetes and to determine whether efpeglenatide's effect varies with increasing FIB-4 severity. MATERIALS AND METHODS: AMPLITUDE-O trial data were used to estimate the relationship of FIB-4 score categories to the hazard of MACE, expanded MACE, and MACE or death. Interactions on these outcomes between baseline FIB-4 score, and between FIB-4 score and efpeglenatide were also assessed. RESULTS: Baseline FIB-4 score was available for 4059 participants (99.6%) allowing subdivision of the population in tertiles. During a median follow-up of 1.8 years, numerical increases in the incidence of all 3 outcomes did not change significantly across tertiles of FIB-4 score (P for trend ≥ 0.25) with negligible relationship of the score to incident outcomes (MACE HR, per 1 SD higher score, 95% CI: 1.00, 0.89-1.13). Efpeglenatide's effect on all MACE outcomes did not vary across FIB-4 tertiles (all interaction p values ≥ 0.64). CONCLUSIONS: In high-risk people with type 2 diabetes, the degree of liver fibrosis, as estimated by FIB-4 score, was not related to incident cardiovascular outcomes. The beneficial effect of efpeglenatide on these outcomes is independent of FIB-4 category.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/mortalidade , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/mortalidade , Idoso , Resultado do Tratamento , Fatores de Tempo , Medição de Risco , Incidência , Valor Preditivo dos Testes , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/efeitos adversos , Fatores de Risco , Biomarcadores/sangue , Incretinas/uso terapêutico , Incretinas/efeitos adversos , Índice de Gravidade de Doença
20.
Cardiovasc Diabetol ; 23(1): 146, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685051

RESUMO

BACKGROUND: The GLP-1 receptor agonist liraglutide is used to treat hyperglycemia in type 2 diabetes but is also known to induce weight loss, preserve the beta cell and reduce cardiovascular risk. The mechanisms underlying these effects are however still not completely known. Herein we explore the effect of liraglutide on markers of immune cell activity in a population of obese individuals with prediabetes or newly diagnosed type 2 diabetes mellitus. METHOD: Plasma levels of the monocyte/macrophage markers, soluble (s)CD163 and sCD14, the neutrophil markers myeloperoxidase (MPO) and neutrophil gelatinase-associated lipocalin (NGAL),the T-cell markers sCD25 and T-cell immunoglobulin mucin domain-3 (sTIM-3) and the inflammatory marker TNF superfamily (TNFSF) member 14 (LIGHT/TNFSF14) were measured by enzyme-linked immunosorbent assays in obese individuals with prediabetes or diabetes diagnosed within the last 12 months, prior to and after comparable weight loss achieved with lifestyle changes (n = 20) or liraglutide treatment (n = 20), and in healthy subjects (n = 13). RESULTS: At baseline, plasma levels of the macrophage marker sCD163, and the inflammatory marker LIGHT were higher in cases as compared to controls. Plasma levels of sCD14, NGAL, sTIM-3 and sCD25 did not differ at baseline between patients and controls. After weight reduction following lifestyle intervention or liraglutide treatment, sCD163 decreased significantly in the liraglutide group vs. lifestyle (between-group difference p = 0.023, adjusted for visceral adipose tissue and triglycerides basal values). MPO and LIGHT decreased significantly only in the liraglutide group (between group difference not significant). Plasma levels of MPO and in particular sCD163 correlated with markers of metabolic dysfunction and inflammation. After weight loss, only sCD163 showed a trend for decreased levels during OGTT, both in the whole cohort as in those of liraglutide vs lifestyle group. CONCLUSION: Weight loss following treatment with liraglutide was associated with reduced circulating levels of sCD163 when compared to the same extent of weight loss after lifestyle changes. This might contribute to reduced cardiometabolic risk in individuals receiving treatment with liraglutide.


Assuntos
Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Biomarcadores , Diabetes Mellitus Tipo 2 , Incretinas , Liraglutida , Obesidade , Estado Pré-Diabético , Receptores de Superfície Celular , Comportamento de Redução do Risco , Redução de Peso , Humanos , Liraglutida/uso terapêutico , Liraglutida/efeitos adversos , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/terapia , Redução de Peso/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Feminino , Obesidade/diagnóstico , Obesidade/sangue , Obesidade/terapia , Biomarcadores/sangue , Antígenos de Diferenciação Mielomonocítica/sangue , Estado Pré-Diabético/sangue , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/terapia , Estado Pré-Diabético/tratamento farmacológico , Receptores de Superfície Celular/sangue , Resultado do Tratamento , Antígenos CD/sangue , Incretinas/uso terapêutico , Incretinas/efeitos adversos , Incretinas/sangue , Adulto , Estudos de Casos e Controles , Fatores de Tempo , Regulação para Baixo , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/efeitos adversos , Idoso
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