Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.355
Filtrar
1.
Genes Dev ; 34(17-18): 1177-1189, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32792353

RESUMO

Dysregulation of the ubiquitin-proteasomal system (UPS) enables pathogenic accumulation of disease-driving proteins in neurons across a host of neurological disorders. However, whether and how the UPS contributes to oligodendrocyte dysfunction and repair after white matter injury (WMI) remains undefined. Here we show that the E3 ligase VHL interacts with Daam2 and their mutual antagonism regulates oligodendrocyte differentiation during development. Using proteomic analysis of the Daam2-VHL complex coupled with conditional genetic knockout mouse models, we further discovered that the E3 ubiquitin ligase Nedd4 is required for developmental myelination through stabilization of VHL via K63-linked ubiquitination. Furthermore, studies in mouse demyelination models and white matter lesions from patients with multiple sclerosis corroborate the function of this pathway during remyelination after WMI. Overall, these studies provide evidence that a signaling axis involving key UPS components contributes to oligodendrocyte development and repair and reveal a new role for Nedd4 in glial biology.


Assuntos
Diferenciação Celular , Proteínas dos Microfilamentos/metabolismo , Ubiquitina-Proteína Ligases Nedd4/metabolismo , Regeneração Nervosa/genética , Doenças do Sistema Nervoso/genética , Oligodendroglia/fisiologia , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Animais , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Camundongos , Camundongos Knockout , Esclerose Múltipla/fisiopatologia , Bainha de Mielina/genética , Doenças do Sistema Nervoso/fisiopatologia , Oligodendroglia/citologia , Estabilidade Proteica , Ubiquitinação/genética
2.
Trends Biochem Sci ; 48(1): 40-52, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35871147

RESUMO

In eukaryotic cells, oxidative protein folding occurs in the lumen of the endoplasmic reticulum (ER), catalyzed by ER sulfhydryl oxidase 1 (Ero1) and protein disulfide isomerase (PDI). The efficiency and fidelity of oxidative protein folding are vital for the function of secretory cells. Here, we summarize oxidative protein folding in yeast, plants, and mammals, and discuss how the conformation and activity of human Ero1-PDI machinery is regulated through various post-translational modifications (PTMs). We propose that oxidative protein folding fidelity and ER redox homeostasis are maintained by both the precise control of Ero1 oxidase activity and the division of labor between PDI family members. We also discuss how deregulated Ero1-PDI functions contribute to human diseases and can be leveraged for therapeutic interventions.


Assuntos
Isomerases de Dissulfetos de Proteínas , Dobramento de Proteína , Animais , Humanos , Isomerases de Dissulfetos de Proteínas/metabolismo , Oxirredução , Saccharomyces cerevisiae/metabolismo , Retículo Endoplasmático/metabolismo , Estresse Oxidativo , Mamíferos
3.
N Engl J Med ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38828946

RESUMO

BACKGROUND: Osimertinib is a recommended treatment for advanced non-small-cell lung cancer (NSCLC) with an epidermal growth factor receptor (EGFR) mutation and as adjuvant treatment for resected EGFR-mutated NSCLC. EGFR-tyrosine kinase inhibitors have shown preliminary efficacy in unresectable stage III EGFR-mutated NSCLC. METHODS: In this phase 3, double-blind, placebo-controlled trial, we randomly assigned patients with unresectable EGFR-mutated stage III NSCLC without progression during or after chemoradiotherapy to receive osimertinib or placebo until disease progression occurred (as assessed by blinded independent central review) or the regimen was discontinued. The primary end point was progression-free survival as assessed by blinded independent central review. RESULTS: A total of 216 patients who had undergone chemoradiotherapy were randomly assigned to receive osimertinib (143 patients) or placebo (73 patients). Osimertinib resulted in a significant progression-free survival benefit as compared with placebo: the median progression-free survival was 39.1 months with osimertinib versus 5.6 months with placebo, with a hazard ratio for disease progression or death of 0.16 (95% confidence interval [CI], 0.10 to 0.24; P<0.001). The percentage of patients who were alive and progression free at 12 months was 74% (95% CI, 65 to 80) with osimertinib and 22% (95% CI, 13 to 32) with placebo. Interim overall survival data (maturity, 20%) showed 36-month overall survival among 84% of patients with osimertinib (95% CI, 75 to 89) and 74% with placebo (95% CI, 57 to 85), with a hazard ratio for death of 0.81 (95% CI, 0.42 to 1.56; P = 0.53). The incidence of adverse events of grade 3 or higher was 35% in the osimertinib group and 12% in the placebo group; radiation pneumonitis (majority grade, 1 to 2) was reported in 48% and 38%, respectively. No new safety concerns emerged. CONCLUSIONS: Treatment with osimertinib resulted in significantly longer progression-free survival than placebo in patients with unresectable stage III EGFR-mutated NSCLC. (Funded by AstraZeneca; LAURA ClinicalTrials.gov number, NCT03521154.).

4.
Proc Natl Acad Sci U S A ; 121(14): e2319233121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38547064

RESUMO

Chemical transformations near plasmonic metals have attracted increasing attention in the past few years. Specifically, reactions occurring within plasmonic nanojunctions that can be detected via surface and tip-enhanced Raman (SER and TER) scattering were the focus of numerous reports. In this context, even though the transition between localized and nonlocal (quantum) plasmons at nanojunctions is documented, its implications on plasmonic chemistry remain poorly understood. We explore the latter through AFM-TER-current measurements. We use two molecules: i) 4-mercaptobenzonitrile (MBN) that reports on the (non)local fields and ii) 4-nitrothiophenol (NTP) that features defined signatures of its neutral/anionic forms and dimer product, 4,4'-dimercaptoazobenzene (DMAB). The transition from classical to quantum plasmons is established through our optical measurements: It is marked by molecular charging and optical rectification. Simultaneously recorded force and current measurements support our assignments. In the case of NTP, we observe the parent and DMAB product beneath the probe in the classical regime. Further reducing the gap leads to the collapse of DMAB to form NTP anions. The process is reversible: Anions subsequently recombine into DMAB. Our results have significant implications for AFM-based TER measurements and their analysis, beyond the scope of this work. In effect, when precise control over the junction is not possible (e.g., in SER and ambient TER), both classical and quantum plasmons need to be considered in the analysis of plasmonic reactions.

5.
Proc Natl Acad Sci U S A ; 120(35): e2304112120, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37607236

RESUMO

Wnt signaling plays an essential role in developmental and regenerative myelination in the central nervous system. The Wnt signaling pathway is composed of multiple regulatory layers; thus, how these processes are coordinated to orchestrate oligodendrocyte (OL) development remains unclear. Here, we show CK2α, a Wnt/ß-catenin signaling Ser/Thr kinase, phosphorylates Daam2, inhibiting its function and Wnt activity during OL development. Intriguingly, we found Daam2 phosphorylation differentially impacts distinct stages of OL development, accelerating early differentiation followed by decelerating maturation and myelination. Application toward white matter injury revealed CK2α-mediated Daam2 phosphorylation plays a protective role for developmental and behavioral recovery after neonatal hypoxia, while promoting myelin repair following adult demyelination. Together, our findings identify a unique regulatory node in the Wnt pathway that regulates OL development via protein phosphorylation-induced signaling complex instability and highlights a new biological mechanism for myelin restoration.


Assuntos
Substância Branca , Fosforilação , Bainha de Mielina , Via de Sinalização Wnt
6.
J Biol Chem ; 300(1): 105502, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38016515

RESUMO

Fatty acid handling and complex lipid synthesis are altered in the kidney cortex of diabetic patients. We recently showed that inhibition of the renin-angiotensin system without changes in glycemia can reverse diabetic kidney disease (DKD) and restore the lipid metabolic network in the kidney cortex of diabetic (db/db) mice, raising the possibility that lipid remodeling may play a central role in DKD. However, the roles of specific enzymes involved in lipid remodeling in DKD have not been elucidated. In the present study, we used this diabetic mouse model and a proximal tubule epithelial cell line (HK2) to investigate the potential relationship between long-chain acyl-CoA synthetase 1 (ACSL1) and lipid metabolism in response to fatty acid exposure and inflammatory signals. We found ACSL1 expression was significantly increased in the kidney cortex of db/db mice, and exposure to palmitate or tumor necrosis factor-α significantly increased Acsl1 mRNA expression in HK-2 cells. In addition, palmitate treatment significantly increased the levels of long-chain acylcarnitines and fatty acyl CoAs in HK2 cells, and these increases were abolished in HK2 cell lines with specific deletion of Acsl1(Acsl1KO cells), suggesting a key role for ACSL1 in fatty acid ß-oxidation. In contrast, tumor necrosis factor-α treatment significantly increased the levels of short-chain acylcarnitines and long-chain fatty acyl CoAs in HK2 cells but not in Acsl1KO cells, consistent with fatty acid channeling to complex lipids. Taken together, our data demonstrate a key role for ACSL1 in regulating lipid metabolism, fatty acid partitioning, and inflammation.


Assuntos
Coenzima A Ligases , Nefropatias Diabéticas , Ácidos Graxos , Animais , Humanos , Camundongos , Coenzima A Ligases/metabolismo , Diabetes Mellitus/patologia , Nefropatias Diabéticas/metabolismo , Ácidos Graxos/metabolismo , Ligases , Palmitatos , Fator de Necrose Tumoral alfa
7.
Circ Res ; 133(1): 71-85, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37232163

RESUMO

BACKGROUND: As a part of natural disease progression, acute kidney injury (AKI) can develop into chronic kidney disease via renal fibrosis and inflammation. LTBP4 (latent transforming growth factor beta binding protein 4) regulates transforming growth factor beta, which plays a role in renal fibrosis pathogenesis. We previously investigated the role of LTBP4 in chronic kidney disease. Here, we examined the role of LTBP4 in AKI. METHODS: LTBP4 expression was evaluated in human renal tissues, obtained from healthy individuals and patients with AKI, using immunohistochemistry. LTBP4 was knocked down in both C57BL/6 mice and human renal proximal tubular cell line HK-2. AKI was induced in mice and HK-2 cells using ischemia-reperfusion injury and hypoxia, respectively. Mitochondrial division inhibitor 1, an inhibitor of DRP1 (dynamin-related protein 1), was used to reduce mitochondrial fragmentation. Gene and protein expression were then examined to assess inflammation and fibrosis. The results of bioenergetic studies for mitochondrial function, oxidative stress, and angiogenesis were assessed. RESULTS: LTBP4 expression was upregulated in the renal tissues of patients with AKI. Ltbp4-knockdown mice showed increased renal tissue injury and mitochondrial fragmentation after ischemia-reperfusion injury, as well as increased inflammation, oxidative stress, and fibrosis, and decreased angiogenesis. in vitro studies using HK-2 cells revealed similar results. The energy profiles of Ltbp4-deficient mice and LTBP4-deficient HK-2 cells indicated decreased ATP production. LTBP4-deficient HK-2 cells exhibited decreased mitochondrial respiration and glycolysis. Human aortic endothelial cells and human umbilical vein endothelial cells exhibited decreased angiogenesis when treated with LTBP4-knockdown conditioned media. Mitochondrial division inhibitor 1 treatment ameliorated inflammation, oxidative stress, and fibrosis in mice and decreased inflammation and oxidative stress in HK-2 cells. CONCLUSIONS: Our study is the first to demonstrate that LTBP4 deficiency increases AKI severity, consequently leading to chronic kidney disease. Potential therapies focusing on LTBP4-associated angiogenesis and LTBP4-regulated DRP1-dependent mitochondrial division are relevant to renal injury.


Assuntos
Injúria Renal Aguda , Insuficiência Renal Crônica , Traumatismo por Reperfusão , Animais , Humanos , Camundongos , Injúria Renal Aguda/prevenção & controle , Células Endoteliais/metabolismo , Fibrose , Inflamação/metabolismo , Rim/metabolismo , Proteínas de Ligação a TGF-beta Latente , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Insuficiência Renal Crônica/complicações , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Fator de Crescimento Transformador beta/metabolismo
8.
EMBO Rep ; 24(8): e56439, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37306027

RESUMO

Oxidative protein folding occurs in the endoplasmic reticulum (ER) to generate disulfide bonds, and the by-product is hydrogen peroxide (H2 O2 ). However, the relationship between oxidative protein folding and senescence remains uncharacterized. Here, we find that the protein disulfide isomerase (PDI), a key oxidoreductase that catalyzes oxidative protein folding, accumulated in aged human mesenchymal stem cells (hMSCs) and deletion of PDI alleviated hMSCs senescence. Mechanistically, knocking out PDI slows the rate of oxidative protein folding and decreases the leakage of ER-derived H2 O2 into the nucleus, thereby decreasing the expression of SERPINE1, which was identified as a key driver of cell senescence. Furthermore, we show that depletion of PDI alleviated senescence in various cell models of aging. Our findings reveal a previously unrecognized role of oxidative protein folding in promoting cell aging, providing a potential target for aging and aging-related disease intervention.


Assuntos
Isomerases de Dissulfetos de Proteínas , Dobramento de Proteína , Humanos , Idoso , Oxirredução , Isomerases de Dissulfetos de Proteínas/genética , Retículo Endoplasmático/metabolismo , Estresse Oxidativo
9.
J Am Chem Soc ; 146(5): 3125-3135, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38288596

RESUMO

The chapter on the thiol-related hydrogen bond (H-bond) and its excited-state intramolecular proton-transfer (ESIPT) reaction was recently opened where compound 4'-diethylamino-3-mercaptoflavone (3NTF) undergoes ESIPT in both cyclohexane solution and solid, giving a 710 nm tautomer emission with an anomalously large Stokes shift of 12,230 cm-1. Considering the thiol H-bond to be unconventional compared to the conventional Pauling-type -OH or -NH H-bond, it is thus essential and timely to probe its fundamental difference between their ESIPT. However, thiol-associated ESIPT tends to be nonemissive due to the dominant nπ* character of the tautomeric lowest excited state. Herein, based on the 3-mercaptoflavone scaffold and π-elongation concept, a new series of 4'-substituted-7-diethylamino-3-mercaptoflavones, NTFs, was designed and synthesized with varied H-bond strength and 690-720 nm tautomeric emission upon ultraviolet (UV) excitation in cyclohexane. The order of their H-bonding strength was experimentally determined to be N-NTF < O-NTF < H-NTF < F-NTF, while the rate of -SH ESIPT measured by fluorescence upconversion was F-NTF (398 fs)-1 < H-NTF (232 fs)-1 < O-NTF (123 fs)-1 < N-NTF (101 fs)-1 in toluene. Unexpectedly, the strongest H-bonded F-NTF gives the slowest ESIPT, which does not conform to the traditional ESIPT model. The results are rationalized by the trend of carbonyl oxygen basicity rather than -SH acidity. Namely, the thiol acidity relevant to the H-bond strength plays a minor role in the driving force of ESIPT. Instead, the proton-accepting strength governs ESIPT. That is to say, the noncanonical thiol H-bonding system undergoes an unconventional type of ESIPT.

10.
EMBO J ; 39(10): e103841, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32149426

RESUMO

Accumulated unfolded proteins in the endoplasmic reticulum (ER) trigger the unfolded protein response (UPR) to increase ER protein folding capacity. ER proteostasis and UPR signaling need to be regulated in a precise and timely manner. Here, we identify phosphorylation of protein disulfide isomerase (PDI), one of the most abundant and critical folding catalysts in the ER, as an early event during ER stress. The secretory pathway kinase Fam20C phosphorylates Ser357 of PDI and responds rapidly to various ER stressors. Phosphorylation of Ser357 induces an open conformation of PDI and turns it from a "foldase" into a "holdase", which is critical for preventing protein misfolding in the ER. Phosphorylated PDI also binds to the lumenal domain of IRE1α, a major UPR signal transducer, and attenuates excessive IRE1α activity. Importantly, PDI-S359A knock-in mice display enhanced IRE1α activation and liver damage under acute ER stress. We conclude that the Fam20C-PDI axis constitutes a post-translational response to maintain ER proteostasis and plays a vital role in protecting against ER stress-induced cell death.


Assuntos
Caseína Quinase I/metabolismo , Endorribonucleases/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Pró-Colágeno-Prolina Dioxigenase/química , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Isomerases de Dissulfetos de Proteínas/química , Isomerases de Dissulfetos de Proteínas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Estresse do Retículo Endoplasmático , Feminino , Células HeLa , Células Hep G2 , Humanos , Masculino , Camundongos , Modelos Moleculares , Fosforilação , Conformação Proteica , Proteostase , Resposta a Proteínas não Dobradas
11.
Cancer Immunol Immunother ; 73(9): 175, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953994

RESUMO

Tumor immunotherapies targeting PD-(L)1 exhibit anti-tumor efficacy in only 10-30% of patients with various cancers. Literature has demonstrated that a "hot tumor" which contains high T lymphocytes in the tumor microenvironment exhibits a better response to immunotherapies than a "cold tumor." This study aimed to investigate whether tumor-intrinsic IFNα and CXCL10 determine the recruitment and activation of CD8+ T cells to become "hot tumor." In this study, we found that CXCL10 overexpressed in a variety of tumors including lung, colon, and liver tumors with a correlation with PD-L1. High PD-L1 and CXCL10 are associated with better survival rates in tumor patients receiving immunotherapies. IFNs-downstream transcriptional factor IRF-1 and STAT1 were correlated with PD-L1 and CXCL10 expression. We demonstrated that IRF-1 and STAT1 were both bound with the promoters of PD-L1 and CXCL10, sharing the same signaling pathway and determining IFNs-mediated PD-L1 and CXCL10 expression. In addition, IFNα significantly increased activation marker IFNγ in PBMCs, promoting M1 type monocyte differentiation, CD4+ T, and CD8+ T cell activation. Particularly, we found that CD8+ T lymphocytes abundantly expressed CXCR3, a receptor of CXCL10, by flow cytometry, indicating that tumor-intrinsic CXCL10 potentially recruited CD8+ T in tumor microenvironment. To demonstrate the hypothesis, immunotherapy-sensitive CT26 and immunotherapy-resistant LL/2 were used and we found that CT26 cells exhibited higher IFNα, IFNγ, CXCL10, and PD-L1 levels compared to LL/2, leading to higher IFNγ expression in mouse splenocytes. Moreover, we found that CD8+ T cells were recruited by CXCL10 in vitro, whereas SCH546738, an inhibitor of CXCR3, inhibited T cell migration and splenocytes-mediated anti-tumor effect. We then confirmed that CT26-derived tumor was sensitive to αPD-L1 immunotherapy and LL/2-tumor was resistant, whereas αPD-L1 significantly increased T lymphocyte activation marker CD107a in CT26-derived BALB/c mice. In conclusion, this study revealed that CXCL10 expression is correlated with PD-L1 in tumors, sharing the same signaling pathway and associating with better immunotherapeutic efficacy. Further evidence in the syngeneic tumor models demonstrated that immunotherapy-sensitive CT26 intrinsically exhibited higher IFNα and CXCL10 compared to immunotherapy-resistant LL/2 to recruit and activate CD8+ T cells in the tumor microenvironment, exhibiting "hot tumor" characteristic of sensitizing αPD-L1 immunotherapies.


Assuntos
Quimiocina CXCL10 , Imunoterapia , Interferon-alfa , Microambiente Tumoral , Quimiocina CXCL10/metabolismo , Quimiocina CXCL10/imunologia , Microambiente Tumoral/imunologia , Animais , Camundongos , Humanos , Imunoterapia/métodos , Neoplasias/imunologia , Neoplasias/terapia , Ativação Linfocitária/imunologia , Linhagem Celular Tumoral , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Antígeno B7-H1/metabolismo , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Feminino , Fator de Transcrição STAT1/metabolismo
12.
Radiology ; 311(3): e231937, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38916510

RESUMO

Background Diagnosing osteoporosis is challenging due to its often asymptomatic presentation, which highlights the importance of providing screening for high-risk populations. Purpose To evaluate the effectiveness of dual-energy x-ray absorptiometry (DXA) screening in high-risk patients with osteoporosis identified by an artificial intelligence (AI) model using chest radiographs. Materials and Methods This randomized controlled trial conducted at an academic medical center included participants 40 years of age or older who had undergone chest radiography between January and December 2022 without a history of DXA examination. High-risk participants identified with the AI-enabled chest radiographs were randomly allocated to either a screening group, which was offered fully reimbursed DXA examinations between January and June 2023, or a control group, which received usual care, defined as DXA examination by a physician or patient on their own initiative without AI intervention. A logistic regression was used to test the difference in the primary outcome, new-onset osteoporosis, between the screening and control groups. Results Of the 40 658 enrolled participants, 4912 (12.1%) were identified by the AI model as high risk, with 2456 assigned to the screening group (mean age, 71.8 years ± 11.5 [SD]; 1909 female) and 2456 assigned to the control group (mean age, 72.1 years ± 11.8; 1872 female). A total of 315 of 2456 (12.8%) participants in the screening group underwent fully reimbursed DXA, and 237 of 315 (75.2%) were identified with new-onset osteoporosis. After including DXA results by means of usual care in both screening and control groups, the screening group exhibited higher rates of osteoporosis detection (272 of 2456 [11.1%] vs 27 of 2456 [1.1%]; odds ratio [OR], 11.2 [95% CI: 7.5, 16.7]; P < .001) compared with the control group. The ORs of osteoporosis diagnosis were increased in screening group participants who did not meet formalized criteria for DXA compared with those who did (OR, 23.2 [95% CI: 10.2, 53.1] vs OR, 8.0 [95% CI: 5.0, 12.6]; interactive P = .03). Conclusion Providing DXA screening to a high-risk group identified with AI-enabled chest radiographs can effectively diagnose more patients with osteoporosis. Clinical trial registration no. NCT05721157 © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Smith and Rothenberg in this issue.


Assuntos
Absorciometria de Fóton , Redes Neurais de Computação , Osteoporose , Radiografia Torácica , Humanos , Feminino , Osteoporose/diagnóstico por imagem , Masculino , Radiografia Torácica/métodos , Absorciometria de Fóton/métodos , Idoso , Programas de Rastreamento/métodos , Pessoa de Meia-Idade
13.
Crit Care Med ; 52(2): 237-247, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38095506

RESUMO

OBJECTIVES: We aimed to develop a computer-aided detection (CAD) system to localize and detect the malposition of endotracheal tubes (ETTs) on portable supine chest radiographs (CXRs). DESIGN: This was a retrospective diagnostic study. DeepLabv3+ with ResNeSt50 backbone and DenseNet121 served as the model architecture for segmentation and classification tasks, respectively. SETTING: Multicenter study. PATIENTS: For the training dataset, images meeting the following inclusion criteria were included: 1) patient age greater than or equal to 20 years; 2) portable supine CXR; 3) examination in emergency departments or ICUs; and 4) examination between 2015 and 2019 at National Taiwan University Hospital (NTUH) (NTUH-1519 dataset: 5,767 images). The derived CAD system was tested on images from chronologically (examination during 2020 at NTUH, NTUH-20 dataset: 955 images) or geographically (examination between 2015 and 2020 at NTUH Yunlin Branch [YB], NTUH-YB dataset: 656 images) different datasets. All CXRs were annotated with pixel-level labels of ETT and with image-level labels of ETT presence and malposition. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: For the segmentation model, the Dice coefficients indicated that ETT would be delineated accurately (NTUH-20: 0.854; 95% CI, 0.824-0.881 and NTUH-YB: 0.839; 95% CI, 0.820-0.857). For the classification model, the presence of ETT could be accurately detected with high accuracy (area under the receiver operating characteristic curve [AUC]: NTUH-20, 1.000; 95% CI, 0.999-1.000 and NTUH-YB: 0.994; 95% CI, 0.984-1.000). Furthermore, among those images with ETT, ETT malposition could be detected with high accuracy (AUC: NTUH-20, 0.847; 95% CI, 0.671-0.980 and NTUH-YB, 0.734; 95% CI, 0.630-0.833), especially for endobronchial intubation (AUC: NTUH-20, 0.991; 95% CI, 0.969-1.000 and NTUH-YB, 0.966; 95% CI, 0.933-0.991). CONCLUSIONS: The derived CAD system could localize ETT and detect ETT malposition with excellent performance, especially for endobronchial intubation, and with favorable potential for external generalizability.


Assuntos
Aprendizado Profundo , Medicina de Emergência , Humanos , Estudos Retrospectivos , Intubação Intratraqueal/efeitos adversos , Intubação Intratraqueal/métodos , Hospitais Universitários
14.
Hepatology ; 77(2): 379-394, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35073601

RESUMO

BACKGROUND AND AIMS: Both nuclear and cytoplasmic overexpression of metastatic tumor antigen 1 (MTA1) contributes to tumorigenesis of HCC. Most studies have focused on nuclear MTA1 whose function is mainly a chromatin modifier regulating the expression of various cancer-promoting genes. By contrast, the molecular mechanisms of cytoplasmic MTA1 in carcinogenesis remain elusive. Here, we reveal a role of MTA1 in posttranscriptional gene regulation. APPROACH AND RESULTS: We conducted the in vitro and in vivo RNA-protein interaction assays indicating that MTA1 could bind directly to the 3'-untranslated region of MYC RNA. Mutation at the first glycine of the conserved GXXG loop within a K-homology II domain-like structure in MTA1 (G78D) resulted in the loss of RNA-binding activity. We used gain- and loss-of-function strategy showing that MTA1, but not the G78D mutant, extended the half-life of MYC and protected it from the lethal -7-mediated degradation. The G78D mutant exhibited lower activity in promoting tumorigenesis than wild-type in vitro and in vivo. Furthermore, RNA-immunoprecipitation sequencing analysis demonstrated that MTA1 binds various oncogenesis-related mRNAs besides MYC . The clinical relevance of cytoplasmic MTA1 and its interaction with MYC were investigated using HBV-HCC cohorts with or without early recurrence. The results showed that higher cytoplasmic MTA1 level and MTA1- MYC interaction were associated with early recurrence. CONCLUSIONS: MTA1 is a generic RNA-binding protein. Cytoplasmic MTA1 and its binding to MYC is associated with early recurrence in patients with HBV-HCC. This function enables it to regulate gene expression posttranscriptionally and contributes to hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Transativadores/genética , Transativadores/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Antígenos de Neoplasias , Carcinogênese/genética , RNA , Regulação Neoplásica da Expressão Gênica
15.
Rev Cardiovasc Med ; 25(4): 124, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-39076571

RESUMO

Background: Galectin-3 is implicated in the pathogenesis of inflammation and atherosclerosis. Peripheral arterial disease (PAD), characterized by a reduced ankle-brachial index (ABI), is a prognostic marker for mortality in patients on hemodialysis. We investigated the relationship between serum galectin-3 levels and PAD in patients undergoing regular hemodialysis. Methods: We carried out a cross-sectional study at a medical center, involving 92 participants. Serum galectin-3 levels were assessed by a commercially available enzyme-linked immunosorbent assay. ABI measurement was done with an automatic device based on oscillometry. Participants were categorized into two groups, normal and low ABI, based on a 0.9 cut-off point. Results: Eighteen patients (19.6%) exhibited a low ABI. In individuals with low ABIs, we observed a greater prevalence of diabetes mellitus, elevated serum C-reactive protein (CRP) levels, increased galectin-3 levels, and lower serum creatinine levels. Furthermore, serum galectin-3 levels (odds ratio [OR]: 1.056, 95% confidence interval [CI]: 1.003-1.112, p = 0.037) and CRP (per 0.1 mg/dL increment, OR: 1.195, 95% CI: 1.032-1.383, p = 0.017) were identified as independent predictors of PAD. Serum galectin-3 and log-transformed CRP levels were also independently and significantly negatively correlated with the left and right ABI values. Conclusions: Serum galectin-3 levels correlate with PAD in patients undergoing maintenance hemodialysis.

16.
J Biomed Sci ; 31(1): 21, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38350919

RESUMO

BACKGROUND: Cancer susceptibility germline mutations are associated with pancreatic ductal adenocarcinoma (PDAC). However, the hereditary status of PDAC and its impact on survival is largely unknown in the Asian population. METHODS: Exome sequencing was performed on 527 blood samples from PDAC individuals and analyzed for mutations in 80 oncogenic genes. Pathogenic and likely pathogenic (P/LP) germline variants were diagnosed according to the ACMG variant classification categories. The association between germline homologous recombination gene mutations (gHRmut, including BAP1, BRCA1, BRCA2, PALB2, ATM, BLM, BRIP1, CHEK2, NBN, MUTYH, FANCA and FANCC) and the treatment outcomes was explored in patients with stage III/IV diseases treated with first-line (1L) platinum-based versus platinum-free chemotherapy. RESULTS: Overall, 104 of 527 (19.7%) patients carried germline P/LP variants. The most common mutated genes were BRCA2 (3.60%), followed by ATR (2.66%) and ATM (1.9%). After a median follow-up duration of 38.3-months (95% confidence interval, 95% CI 35.0-43.7), the median overall survival (OS) was not significantly different among patients with gHRmut, non-HR germline mutations, or no mutation (P = 0.43). Among the 320 patients with stage III/IV disease who received 1L combination chemotherapy, 32 (10%) had gHRmut. Of them, patients receiving 1L platinum-based chemotherapy exhibited a significantly longer median OS compared to those with platinum-free chemotherapy, 26.1 months (95% CI 12.7-33.7) versus 9.6 months (95% CI 5.9-17.6), P = 0.001. However, the median OS of patients without gHRmut was 14.5 months (95% CI 13.2-16.9) and 12.6 months (95% CI 10.8-14.7) for patients receiving 1L platinum-based and platinum-free chemotherapy, respectively (P = 0.22). These results were consistent after adjusting for potential confounding factors including age, tumor stage, performance status, and baseline CA 19.9 in the multivariate Cox regression analysis. CONCLUSIONS: Our study showed that nearly 20% of Taiwanese PDAC patients carried germline P/LP variants. The longer survival observed in gHRmut patients treated with 1L platinum-based chemotherapy highlights the importance of germline testing for all patients with advanced PDAC at diagnosis.


Assuntos
Mutação em Linhagem Germinativa , Neoplasias Pancreáticas , Humanos , Taiwan , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Recombinação Homóloga , Genes BRCA2 , Proteína BRCA1/genética , Proteína BRCA2/genética
17.
Liver Int ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984849

RESUMO

BACKGROUND AND AIMS: We aimed to explore the risk factors associated with virological and clinical relapse, as well as their impact on overall mortality, in hepatitis B virus (HBV)-infected patients receiving nucleos(t)ide analogues (NUCs) therapy prior to chemotherapy initiation. METHODS: From 2010 to 2020, we conducted a prospective cohort study involving patients with HBV infection undergoing cytotoxic chemotherapy. We utilized the Kaplan-Meier method and Cox proportional hazard regression models to assess risk factors. RESULTS: We observed that TDF or TAF (HR: 2.16, 95% CI 1.06-4.41; p = .034), anthracycline (HR: 1.73, 95% CI 1.10-2.73; p = .018), baseline HBV DNA (HR: 1.55, 95% CI 1.33-1.81; p < .001) and end-of-treatment HBsAg titre >100 IU/mL (HR: 7.81, 95% CI 1.94-31.51; p = .004) were associated with increased risk of virological relapse. Additionally, TDF or TAF (HR: 4.91, 95% CI 1.45-16.64; p = .011), baseline HBV DNA (HR: 1.48, 95% CI 1.10-1.99; p = .009) and end-of-treatment HBsAg titre >100 IU/mL (HR: 6.09, 95% CI .95-38.87; p = .056) were associated with increased risk of clinical relapse. Furthermore, we found that virological relapse (HR: 3.32, 95% CI 1.33-8.32; p = .010) and clinical relapse (HR: 3.59, 95% CI 1.47-8.80; p = .005) significantly correlated with all-cause mortality in HBV patients receiving cytotoxic chemotherapy with prophylactic NUCs therapy. CONCLUSIONS: The risk of virological and clinical relapse was linked to baseline HBV DNA, end-of-treatment HBsAg levels and TDF or TAF for prophylaxis; additionally, experiencing relapse heightens the risk of all-cause mortality. Further research is warranted to explore potential strategies for preventing virological and clinical relapse in high-risk patients.

18.
Biogerontology ; 25(3): 447-459, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38183523

RESUMO

Dietary restriction (DR) is a potential intervention for ameliorating ageing-related damages. Mitochondrial quality control is the key mechanism for regulating cellular functions in skeletal muscle. This study aimed to explore the effect of age and DR on the homeostasis of mitochondrial quality control in skeletal muscle. To study the effect of age on mitochondrial homeostasis, young (3 months old) male C57BL/6J mice were fed ad libitum (AL) until 7 (Young), 14 (Middle), and 19 months (Aged) of age. For the DR intervention, 60% of AL intake was given to the mice at 3 months of age until they reached 19 months of age (16 months). The quadriceps femoris muscle was collected for further analysis. Significant changes in the skeletal muscle were noticed during the transition between middle age and the elderly stages. An accumulation of collagen was observed in the muscle after middle age. Compared with the Middle muscle, Aged muscle displayed a greater expression of VDAC, and lower expressions of mitochondrial dynamic proteins and OXPHOS proteins. The DR intervention attenuated collagen content and elongated the sarcomere length in the skeletal muscle during ageing. In addition, DR adjusted the abnormalities in mitochondrial morphology in the Aged muscle. DR downregulated VDAC expression, but upregulated OPA1 and DRP1 expressions. Taken together, greater pathological changes were noticed in the skeletal muscle during ageing, especially in the transition between middle age and the elderly, whereas early-onset DR attenuated the muscular ageing via normalising partial functions of mitochondria.


Assuntos
Envelhecimento , Restrição Calórica , Camundongos Endogâmicos C57BL , Mitocôndrias Musculares , Músculo Quadríceps , Animais , Masculino , Músculo Quadríceps/metabolismo , Camundongos , Envelhecimento/fisiologia , Envelhecimento/metabolismo , Mitocôndrias Musculares/metabolismo , Colágeno/metabolismo
19.
Clin Transplant ; 38(1): e15163, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37823247

RESUMO

BACKGROUND AND AIM: Limited data are available regarding pre-liver transplantation (LT) bacteremia in adults with end-stage liver disease. In this study, we investigated the risk factors independently associated with pre-LT bacteremia and their effects on clinical outcomes of LT. METHODS: This retrospective study performed between 2010 and 2021 included 1287 LT recipients. The study population was categorized into patients with pre-LT bacteremia and those without pre-LT infection. Pre-LT bacteremia was defined as bacteremia detected within 90 days before LT. RESULTS: Among 1287 LT recipients, 92 (7.1%) developed pre-LT bacteremia. The mean interval between bacteremia and LT was 28.3 ± 19.5 days. Of these 92 patients, seven (7.6%) patients died after LT. Of the 99 microorganisms isolated in this study, gram-negative bacteria were the most common microbes (72.7%). Bacteremia was mainly attributed to spontaneous bacterial peritonitis. The most common pathogen isolated was Escherichia coli (25.2%), followed by Klebsiella pneumoniae (18.2%), and Staphylococcus aureus (15.1%). Multivariate analysis showed that massive ascites (adjusted odds ratio [OR] 1.67, 95% confidence Interval [CI] 1.048-2.687) and a prolonged international normalized ratio for prothrombin time (adjusted OR 1.13, 95% CI 1.074-1.257) were independent risk factors for pre-LT bacteremia in patients with end-stage liver disease. Intensive care unit and in-hospital stay were significantly longer, and in-hospital mortality was significantly higher among LT recipients with pre-LT bacteremia than among those without pre-LT infection. CONCLUSIONS: This study highlights predictors of pre-LT bacteremia in patients with end-stage liver disease. Pre-LT bacteremia increases the post-transplantation mortality risk.


Assuntos
Bacteriemia , Doença Hepática Terminal , Transplante de Fígado , Adulto , Humanos , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Doença Hepática Terminal/complicações , Doença Hepática Terminal/cirurgia , Fatores de Risco , Bacteriemia/epidemiologia
20.
J Clin Gastroenterol ; 58(2): 131-135, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36753462

RESUMO

BACKGROUND METHODS: The question prompt list content was derived through a modified Delphi process consisting of 3 rounds. In round 1, experts provided 5 answers to the prompts "What general questions should patients ask when given a new diagnosis of Barrett's esophagus" and "What questions do I not hear patients asking, but given my expertise, I believe they should be asking?" Questions were reviewed and categorized into themes. In round 2, experts rated questions on a 5-point Likert scale. In round 3, experts rerated questions modified or reduced after the previous rounds. Only questions rated as "essential" or "important" were included in Barrett's esophagus question prompt list (BE-QPL). To improve usability, questions were reduced to minimize redundancy and simplified to use language at an eighth-grade level (Fig. 1). RESULTS: Twenty-one esophageal medical and surgical experts participated in both rounds (91% males; median age 52 years). The expert panel comprised of 33% esophagologists, 24% foregut surgeons, and 24% advanced endoscopists, with a median of 15 years in clinical practice. Most (81%), worked in an academic tertiary referral hospital. In this 3-round Delphi technique, 220 questions were proposed in round 1, 122 (55.5%) were accepted into the BE-QPL and reduced down to 76 questions (round 2), and 67 questions (round 3). These 67 questions reached a Flesch Reading Ease of 68.8, interpreted as easily understood by 13 to 15 years olds. CONCLUSIONS: With multidisciplinary input, we have developed a physician-derived BE-QPL to optimize patient-physician communication. Future directions will seek patient feedback to distill the questions further to a smaller number and then assess their usability.


Assuntos
Esôfago de Barrett , Médicos , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Esôfago de Barrett/diagnóstico , Técnica Delphi , Comunicação , Relações Médico-Paciente , Inquéritos e Questionários
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA