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1.
Nat Immunol ; 18(9): 1035-1045, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28759003

RESUMO

MLL4 is an essential subunit of the histone H3 Lys4 (H3K4)-methylation complexes. We found that MLL4 deficiency compromised the development of regulatory T cells (Treg cells) and resulted in a substantial decrease in monomethylated H3K4 (H3K4me1) and chromatin interaction at putative gene enhancers, a considerable portion of which were not direct targets of MLL4 but were enhancers that interacted with MLL4-bound sites. The decrease in H3K4me1 and chromatin interaction at the enhancers not bound by MLL4 correlated with MLL4 binding at distant interacting regions. Deletion of an upstream MLL4-binding site diminished the abundance of H3K4me1 at the regulatory elements of the gene encoding the transcription factor Foxp3 that were looped to the MLL4-binding site and compromised both the thymic differentiation and the inducible differentiation of Treg cells. We found that MLL4 catalyzed methylation of H3K4 at distant unbound enhancers via chromatin looping, which identifies a previously unknown mechanism for regulating the T cell enhancer landscape and affecting Treg cell differentiation.


Assuntos
Diferenciação Celular/genética , Cromatina/metabolismo , Fatores de Transcrição Forkhead/genética , Histona-Lisina N-Metiltransferase/genética , Histonas/metabolismo , Linfócitos T Reguladores , Animais , Sistemas CRISPR-Cas , Citocinas/imunologia , Citometria de Fluxo , Regulação da Expressão Gênica , Immunoblotting , Técnicas In Vitro , Metilação , Camundongos
2.
Genes Dev ; 35(9-10): 713-728, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33888555

RESUMO

MED1 often serves as a surrogate of the general transcription coactivator complex Mediator for identifying active enhancers. MED1 is required for phenotypic conversion of fibroblasts to adipocytes in vitro, but its role in adipose development and expansion in vivo has not been reported. Here, we show that MED1 is not generally required for transcription during adipogenesis in culture and that MED1 is dispensable for adipose development in mice. Instead, MED1 is required for postnatal adipose expansion and the induction of fatty acid and triglyceride synthesis genes after pups switch diet from high-fat maternal milk to carbohydrate-based chow. During adipogenesis, MED1 is dispensable for induction of lineage-determining transcription factors (TFs) PPARγ and C/EBPα but is required for lipid accumulation in the late phase of differentiation. Mechanistically, MED1 controls the induction of lipogenesis genes by facilitating lipogenic TF ChREBP- and SREBP1a-dependent recruitment of Mediator to active enhancers. Together, our findings identify a cell- and gene-specific regulatory role of MED1 as a lipogenesis coactivator required for postnatal adipose expansion.


Assuntos
Tecido Adiposo/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/genética , Lipogênese/genética , Subunidade 1 do Complexo Mediador/genética , Subunidade 1 do Complexo Mediador/metabolismo , Tecido Adiposo/metabolismo , Tecido Adiposo Marrom/embriologia , Animais , Células Cultivadas , Dieta , Camundongos , Ligação Proteica/genética
3.
Cell ; 153(6): 1266-80, 2013 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-23727112

RESUMO

The DNA damage response (DDR) protein 53BP1 protects DNA ends from excessive resection in G1, and thereby favors repair by nonhomologous end-joining (NHEJ) as opposed to homologous recombination (HR). During S phase, BRCA1 antagonizes 53BP1 to promote HR. The pro-NHEJ and antirecombinase functions of 53BP1 are mediated in part by RIF1, the only known factor that requires 53BP1 phosphorylation for its recruitment to double-strand breaks (DSBs). Here, we show that a 53BP1 phosphomutant, 53BP18A, comprising alanine substitutions of the eight most N-terminal S/TQ phosphorylation sites, mimics 53BP1 deficiency by restoring genome stability in BRCA1-deficient cells yet behaves like wild-type 53BP1 with respect to immunoglobulin class switch recombination (CSR). 53BP18A recruits RIF1 but fails to recruit the DDR protein PTIP to DSBs, and disruption of PTIP phenocopies 53BP18A. We conclude that 53BP1 promotes productive CSR and suppresses mutagenic DNA repair through distinct phosphodependent interactions with RIF1 and PTIP.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Reparo do DNA por Junção de Extremidades , Proteínas de Ligação a DNA/metabolismo , Switching de Imunoglobulina , Proteínas Nucleares/metabolismo , Proteínas de Ligação a Telômeros/metabolismo , Animais , Linfócitos B/metabolismo , Proteína BRCA1/metabolismo , Proteínas Cromossômicas não Histona/genética , Quebras de DNA de Cadeia Dupla , Proteínas de Ligação a DNA/genética , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Fibroblastos/metabolismo , Instabilidade Genômica , Camundongos , Mutação , Proteína 1 de Ligação à Proteína Supressora de Tumor p53
4.
Mol Cell ; 78(6): 1114-1132.e10, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32446320

RESUMO

Bromodomain-containing protein 4 (BRD4) is a cancer therapeutic target in ongoing clinical trials disrupting primarily BRD4-regulated transcription programs. The role of BRD4 in cancer has been attributed mainly to the abundant long isoform (BRD4-L). Here we show, by isoform-specific knockdown and endogenous protein detection, along with transgene expression, the less abundant BRD4 short isoform (BRD4-S) is oncogenic while BRD4-L is tumor-suppressive in breast cancer cell proliferation and migration, as well as mammary tumor formation and metastasis. Through integrated RNA-seq, genome-wide ChIP-seq, and CUT&RUN association profiling, we identify the Engrailed-1 (EN1) homeobox transcription factor as a key BRD4-S coregulator, particularly in triple-negative breast cancer. BRD4-S and EN1 comodulate the extracellular matrix (ECM)-associated matrisome network, including type II cystatin gene cluster, mucin 5, and cathepsin loci, via enhancer regulation of cancer-associated genes and pathways. Our work highlights the importance of targeted therapies for the oncogenic, but not tumor-suppressive, activity of BRD4.


Assuntos
Neoplasias da Mama/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/fisiologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/fisiologia , Animais , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Genes Homeobox , Proteínas de Homeodomínio/metabolismo , Humanos , Camundongos , Invasividade Neoplásica , Proteínas Nucleares/metabolismo , Isoformas de Proteínas/metabolismo , Proteínas/antagonistas & inibidores , Proteínas/metabolismo , Transcrição Gênica/genética , Neoplasias de Mama Triplo Negativas/genética
5.
Nature ; 599(7886): 576-581, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34819684

RESUMO

Efficient magnetic control of electronic conduction is at the heart of spintronic functionality for memory and logic applications1,2. Magnets with topological band crossings serve as a good material platform for such control, because their topological band degeneracy can be readily tuned by spin configurations, dramatically modulating electronic conduction3-10. Here we propose that the topological nodal-line degeneracy of spin-polarized bands in magnetic semiconductors induces an extremely large angular response of magnetotransport. Taking a layered ferrimagnet, Mn3Si2Te6, and its derived compounds as a model system, we show that the topological band degeneracy, driven by chiral molecular orbital states, is lifted depending on spin orientation, which leads to a metal-insulator transition in the same ferrimagnetic phase. The resulting variation of angular magnetoresistance with rotating magnetization exceeds a trillion per cent per radian, which we call colossal angular magnetoresistance. Our findings demonstrate that magnetic nodal-line semiconductors are a promising platform for realizing extremely sensitive spin- and orbital-dependent functionalities.

6.
Brief Bioinform ; 25(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38349059

RESUMO

Standigm ASK™ revolutionizes healthcare by addressing the critical challenge of identifying pivotal target genes in disease mechanisms-a fundamental aspect of drug development success. Standigm ASK™ integrates a unique combination of a heterogeneous knowledge graph (KG) database and an attention-based neural network model, providing interpretable subgraph evidence. Empowering users through an interactive interface, Standigm ASK™ facilitates the exploration of predicted results. Applying Standigm ASK™ to idiopathic pulmonary fibrosis (IPF), a complex lung disease, we focused on genes (AMFR, MDFIC and NR5A2) identified through KG evidence. In vitro experiments demonstrated their relevance, as TGFß treatment induced gene expression changes associated with epithelial-mesenchymal transition characteristics. Gene knockdown reversed these changes, identifying AMFR, MDFIC and NR5A2 as potential therapeutic targets for IPF. In summary, Standigm ASK™ emerges as an innovative KG and artificial intelligence platform driving insights in drug target discovery, exemplified by the identification and validation of therapeutic targets for IPF.


Assuntos
Inteligência Artificial , Fibrose Pulmonar Idiopática , Humanos , Reconhecimento Automatizado de Padrão , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/genética , Pulmão/metabolismo
7.
Proc Natl Acad Sci U S A ; 120(37): e2221929120, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37669380

RESUMO

The endoplasmic reticulum (ER) is selectively degraded by ER-phagy to maintain cell homeostasis. α-synuclein accumulates in the ER, causing ER stress that contributes to neurodegeneration in Parkinson's disease (PD), but the role of ER-phagy in α-synuclein modulation is largely unknown. Here, we investigated the mechanisms by which ER-phagy selectively recognizes α-synuclein for degradation in the ER. We found that ER-phagy played an important role in the degradation of α-synuclein and recovery of ER function through interaction with FAM134B, where calnexin is required for the selective FAM134B-mediated α-synuclein clearance via ER-phagy. Overexpression of α-synuclein in the ER of the substantia nigra (SN) resulted in marked loss of dopaminergic neurons and motor deficits, mimicking PD characteristics. However, enhancement of ER-phagy using FAM134B overexpression in the SN exerted neuroprotective effects on dopaminergic neurons and recovered motor performance. These data suggest that ER-phagy represents a specific ER clearance mechanism for the degradation of α-synuclein.


Assuntos
Fármacos Neuroprotetores , Doença de Parkinson , Humanos , alfa-Sinucleína , Retículo Endoplasmático , Autofagia
8.
Nucleic Acids Res ; 51(11): 5634-5646, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37158237

RESUMO

In this study, we specifically visualized DNA molecules at their AT base pairs after in vitro phage ejection. Our AT-specific visualization revealed that either end of the DNA molecule could be ejected first with a nearly 50% probability. This observation challenges the generally accepted theory of Last In First Out (LIFO), which states that the end of the phage λ DNA that enters the capsid last during phage packaging is the first to be ejected, and that both ends of the DNA are unable to move within the extremely condensed phage capsid. To support our observations, we conducted computer simulations that revealed that both ends of the DNA molecule are randomized, resulting in the observed near 50% probability. Additionally, we found that the length of the ejected DNA by LIFO was consistently longer than that by First In First Out (FIFO) during in vitro phage ejection. Our simulations attributed this difference in length to the stiffness difference of the remaining DNA within the phage capsid. In conclusion, this study demonstrates that a DNA molecule within an extremely dense phage capsid exhibits a degree of mobility, allowing it to switch ends during ejection.


Assuntos
Bacteriófago lambda , DNA Viral , Empacotamento do Genoma Viral , Bacteriófago lambda/fisiologia , DNA Viral/metabolismo , Capsídeo/metabolismo
9.
Curr Issues Mol Biol ; 46(5): 4580-4594, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38785546

RESUMO

The proto-oncogene MYC is frequently dysregulated in patients with diffuse large B-cell lymphoma (DLBCL) and plays a critical role in disease progression. To improve the clinical outcomes of patients with DLBCL, the development of strategies to target MYC is crucial. The use of medicinal plants for developing anticancer drugs has garnered considerable attention owing to their diverse mechanisms of action. In this study, 100 plant extracts of flora from the Republic of Korea were screened to search for novel agents with anti-DLBCL effects. Among them, Ajania pacifica (Nakai) K. Bremer and Humphries extract (APKH) efficiently suppressed the survival of DLBCL cells, while showing minimal toxicity toward normal murine bone marrow cells. APKH suppressed the expression of anti-apoptotic BCL2 family members, causing an imbalance between the pro-apoptotic and anti-apoptotic BCL2 members. This disrupted mitochondrial membrane potential, cytochrome c release, and pro-caspase-3 activation and eventually led to DLBCL cell death. Importantly, MYC expression was markedly downregulated by APKH and ectopic expression of MYC in DLBCL cells abolished the pro-apoptotic effects of APKH. These results demonstrate that APKH exerts anti-DLBCL effects by inhibiting MYC expression. Moreover, when combined with doxorubicin, an essential component of the CHOP regimen (cyclophosphamide, doxorubicin, vincristine, and prednisone), APKH synergistically enhanced the therapeutic effect of doxorubicin. This indicates that APKH may overcome drug resistance, which is common in patients with refractory/relapsed DLBCL. To identify compounds with anti-DLBCL activities in APKH, the chemical profile analysis of APKH was performed using UPLC-QTOF/MSe analysis and assessed for its anticancer activity. Based on the UPLC-QTOF/MSe chemical profiling, it is conceivable that APKH may serve as a novel agent targeting MYC and sensitizing drug-resistant DLBCL cells to CHOP chemotherapy. Further studies to elucidate how the compounds in APKH exert tumor-suppressive role in DLBCL are warranted.

10.
Biochem Biophys Res Commun ; 720: 150072, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-38749187

RESUMO

The Eph receptor, a prototypically large receptor protein tyrosine kinase, interacts with ephrin ligands, forming a bidirectional signaling system that impacts diverse brain functions. Eph receptors and ephrins mediate forward and reverse signaling, affecting neurogenesis, axon guidance, and synaptic signaling. While mammalian studies have emphasized their roles in neurogenesis and synaptic plasticity, the Drosophila counterparts are less studied, especially in glial cells, despite structural similarities. Using RNAi to modulate Eph/ephrin expression in Drosophila neurons and glia, we studied their roles in brain development and sleep and circadian behavior. Knockdown of neuronal ephrin disrupted mushroom body development, while glial knockdown had minimal impact. Surprisingly, disrupting ephrin in neurons or glial cells altered sleep and circadian rhythms, indicating a direct involvement in these behaviors independent from developmental effects. Further analysis revealed distinct sleep phenotypes between neuronal and glial knockdowns, underscoring the intricate interplay within the neural circuits that govern behavior. Glia-specific knockdowns showed altered sleep patterns and reduced circadian rhythmicity, suggesting an intricate role of glia in sleep regulation. Our findings challenge simplistic models of Eph/ephrin signaling limited to neuron-glia communication and emphasize the complexity of the regulatory networks modulating behavior. Future investigations targeting specific glial subtypes will enhance our understanding of Eph/ephrin signaling's role in sleep regulation across species.


Assuntos
Ritmo Circadiano , Efrinas , Corpos Pedunculados , Neuroglia , Neurônios , Transdução de Sinais , Sono , Animais , Neuroglia/metabolismo , Sono/fisiologia , Sono/genética , Ritmo Circadiano/fisiologia , Neurônios/metabolismo , Efrinas/metabolismo , Efrinas/genética , Corpos Pedunculados/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Receptores da Família Eph/metabolismo , Receptores da Família Eph/genética , Drosophila melanogaster/metabolismo , Drosophila melanogaster/fisiologia , Drosophila melanogaster/genética , Drosophila/metabolismo
11.
Nat Methods ; 18(12): 1499-1505, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34824476

RESUMO

Organisms orchestrate cellular functions through transcription factor (TF) interactions with their target genes, although these regulatory relationships are largely unknown in most species. Here we report a high-throughput approach for characterizing TF-target gene interactions across species and its application to 354 TFs across 48 bacteria, generating 17,000 genome-wide binding maps. This dataset revealed themes of ancient conservation and rapid evolution of regulatory modules. We observed rewiring, where the TF sensing and regulatory role is maintained while the arrangement and identity of target genes diverges, in some cases encoding entirely new functions. We further integrated phenotypic information to define new functional regulatory modules and pathways. Finally, we identified 242 new TF DNA binding motifs, including a 70% increase of known Escherichia coli motifs and the first annotation in Pseudomonas simiae, revealing deep conservation in bacterial promoter architecture. Our method provides a versatile tool for functional characterization of genetic pathways in prokaryotes and eukaryotes.


Assuntos
Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Genoma Bacteriano , Motivos de Aminoácidos , Arabidopsis/genética , Sítios de Ligação , Biotina/química , Mapeamento Cromossômico , DNA/química , Código de Barras de DNA Taxonômico , Bases de Dados Genéticas , Escherichia coli/metabolismo , Biblioteca Gênica , Redes Reguladoras de Genes , Fenótipo , Ligação Proteica , Pseudomonas/metabolismo , Especificidade da Espécie , Fatores de Transcrição/metabolismo
12.
Electrophoresis ; 45(9-10): 906-915, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38488745

RESUMO

Targeted bisulfite sequencing using single-base extension (SBE) can be used to measure DNA methylation via capillary electrophoresis on genetic analyzers in forensic labs. Several accurate age prediction models have been reported using this method. However, using different genetic analyzers with different software settings can generate different methylation values, leading to significant errors in age prediction. To address this issue, the study proposes and compares four methods as follows: (1) adjusting methylation values using numerous actual body fluid DNA samples, (2) adjusting methylation values using control DNAs with varying methylation ratios, (3) constructing new age prediction models for each genetic analyzer type, and (4) constructing new age prediction models that could be applied to all types of genetic analyzers. To test the methods for adjusting values using actual body fluid DNA samples, previously reported adjusting equations were used for blood/saliva DNA age prediction markers (ELOVL2, FHL2, KLF14, MIR29B2CHG/C1orf132, and TRIM59). New equations were generated for semen DNA age prediction markers (TTC7B, LOC401324/cg12837463, and LOC729960/NOX4) by drawing polynomial regression lines between the results of the three types of genetic analyzers (3130, 3500, and SeqStudio). The same method was applied to obtain adjustment equations using 11 control DNA samples. To develop new age prediction models for each genetic analyzer type, linear regression analysis was conducted using DNA methylation data from 150 blood, 150 saliva, and 62 semen samples. For the genetic analyzer-independent models, control DNAs were used to formulate equations for calibrating the bias of the data from each genetic analyzer, and linear regression analysis was performed using calibrated body fluid DNA data. In the comparison results, the genetic analyzer-specific models showed the highest accuracy. However, genetic analyzer-independent models through bias adjustment also provided accurate age prediction results, suggesting its use as an alternative in situations with multiple constraints.


Assuntos
Metilação de DNA , DNA , Humanos , Masculino , DNA/análise , DNA/genética , Adulto , Eletroforese Capilar/métodos , Genética Forense/métodos , Pessoa de Meia-Idade , Análise de Sequência de DNA/métodos , Envelhecimento/genética , Adulto Jovem , Sêmen/química , Saliva/química , Idoso , Marcadores Genéticos/genética
13.
Microb Pathog ; : 106771, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38969185

RESUMO

Despite modern advances in food hygiene, food poisoning due to microbial contamination remains a global problem, and poses a great threat to human health. Especially, Listeria monocytogenes and Staphylococcus aureus are gram-positive bacteria found on food-contact surfaces with biofilms. These foodborne pathogens cause a considerable number of food poisoning and infections annually. Ovomucin (OM) is a water-insoluble gel-type glycoprotein in egg whites. Enzymatic hydrolysis can be used to improve the bioactive properties of OM. This study aimed to investigate whether ovomucin hydrolysates (OMHs) produced using five commercial enzymes (Alcalase®, Bromelain, α-Chymotrypsin, Papain, and Pancreatin) can inhibit the biofilm formation of L. monocytogenes ATCC 15313, L. monocytogenes H7962, S. aureus KCCM 11593, and S. aureus 7. Particularly, OMH prepared with papain (OMPP; 500 µg/mL) significantly inhibited biofilm formation in L. monocytogenes ATCC 15313, L. monocytogenes H7962, S. aureus KCCM 11593, and S. aureus 7 by 85.56%, 80.28%, 91.70%, and 79.00%, respectively. In addition, OMPP reduced the metabolic activity, exopolysaccharide production (EPS), adhesion ability, and gene expression associated with the biofilm formation of these bacterial strains. These results suggest that OMH, especially OMPP, exerts anti-biofilm effects against L. monocytogenes and S. aureus. Therefore, OMPP can be used as a natural anti-biofilm agent to control food poisoning in the food industry.

14.
Eur Radiol ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806802

RESUMO

OBJECTIVES: To investigate the imaging features of pancreatic ductal adenocarcinoma (PDAC) with histological large duct pattern. METHODS: Our study included 37 patients (mean age, 66.5 years; 22 women) with surgically proven PDAC with histological large duct pattern, whose imaging features were classified into four types: Type I, solid mass; Type II, predominantly cystic mass with intracystic solid components; Type III, predominantly solid mass with intratumoral cysts; and Type IV, solid mass with peritumoral retention cysts or pseudocysts. Two radiologists independently analyzed both CT and MRI images for the morphological type, presence of abrupt main pancreatic duct (MPD) cutoff, adjacent vascular invasion, diffusion restriction, and reached consensus. RESULTS: On CT, 26 patients (70.3%) had Type I tumors, five (13.5%) had Type II, three (8.1%) had Type III, and three (8.1%) had Type IV. Among the 26 patients with Type I tumors on CT, 16 had tumors with multiple intratumoral cysts within the solid mass on MRI and were subsequently classified as Type III. Accordingly, 10 patients (27.0%) were classified as Type I, five (13.5%) as Type II, 19 (51.7%) as Type III, and three (8.1%) as Type IV on MRI. Of the 37 patients, 27 (73.0%) had an abrupt MPD cutoff, 15 (40.5%) had adjacent vascular invasion, and 25 (67.6%) had diffusion restriction on MRI. CONCLUSIONS: Predominantly solid pancreatic masses with small intratumoral cysts visualized on MRI may be a characteristic imaging finding of PDAC with histological large duct pattern, and differentiate it from conventional PDAC or other cystic pancreatic tumors. CLINICAL RELEVANCE STATEMENT: Radiologists should be familiar with the various imaging features of PDAC with histological large duct pattern and should be aware that it may mimic other solid or cystic tumors of the pancreas. KEY POINTS: Imaging features of pancreatic ductal adenocarcinoma with histological large duct pattern can be classified into four types. This pathology more frequently appears as a predominantly solid mass with intratumoral cysts on MRI than on CT. Adding MRI to CT may help identify pancreatic ductal adenocarcinoma with histological large duct pattern.

15.
Eur Radiol ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38536460

RESUMO

OBJECTIVES: To predict tumor recurrence in patients who underwent surgical resection of ampullary adenocarcinoma using preoperative magnetic resonance (MR) imaging findings combined with clinical findings. METHODS: In this multicenter study, a total of 113 patients (mean age, 62.9 ± 9.8 years; 58 men and 55 women) with ampullary adenocarcinoma who underwent preoperative MR imaging and surgery with margin-negative resection between 2006 and 2017 were retrospectively included. The MR imaging findings were evaluated by two radiologists. Preoperative clinical findings were obtained. Cox proportional regression analyses were used to identify the independent prognostic factors for recurrence-free survival (RFS). A nomogram was created based on the multivariable analysis and was internally validated. RESULTS: Multivariable analysis revealed that presence of infiltrative tumor margin (hazard ratio [HR]: 2.18, p = 0.019), adjacent organ invasion (HR: 3.31, p = 0.006), adjacent vessel invasion (HR: 5.42, p = 0.041), peripancreatic lymph node enlargement (HR: 2.1, p = 0.019), and jaundice (HR: 1.93, p = 0.043) were significantly associated with worse RFS of ampullary adenocarcinoma after surgical resection. These MR imaging and clinical findings were used to construct a nomogram. On internal validation, the calibration plots showed excellent agreement between the predicted probabilities and the actual rates of tumor recurrence, with Harrell's c-index of 0.746. CONCLUSIONS: Combination of preoperative MR imaging and clinical findings can be useful for predicting tumor recurrence after surgical resection of ampullary adenocarcinoma. Identifying these features before surgery may aid in better treatment planning and management of these patients. CLINICAL RELEVANCE STATEMENT: A predictive nomogram using preoperative MR imaging and clinical findings can be useful in estimating the recurrence-free survival after surgical resection of ampullary adenocarcinoma. KEY POINTS: • Presently, tumor size on imaging is the only non-invasive factor that correlates with recurrence-free survival from ampullary adenocarcinoma; other factors are obtained postoperatively. • Infiltrative tumor margin, adjacent organ invasion, adjacent vessel invasion, peripancreatic lymph node enlargement on MRI, and jaundice are significant predictors for recurrence. • A nomogram incorporating significant MR imaging and clinical findings showed good performance in predicting recurrence-free survival, which can help in treatment planning.

16.
BMC Ophthalmol ; 24(1): 58, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326764

RESUMO

PURPOSE: To investigate a novel marker to diagnose posterior staphylomas by measuring the radius of the steepest curvature on the retinal pigment epithelium (RPE) segmentation line using optical coherence tomography (OCT). STUDY DESIGN: Retrospective Cross-sectional Study. METHODS: The authors developed a prototype software to measure the radius of curvature on the RPE segmentation line of OCT. Twelve images of 9-mm radial OCT scans were used. The radius of curvature was measured at the steepest area of the RPE segmentation line, and the macular curvature (MC) index was calculated based on its reciprocal. Based on the wide-field fundus findings, the study sample was divided into three groups: definite posterior staphyloma, no posterior staphyloma, and undetermined. The differences of MC index among the groups and the correlation between the MC index, age, and axial length were analyzed. RESULTS: The present study analyzed 268 eyes, with 54 (20.1%) with definite posterior staphyloma, 202 (75.4%) with no posterior staphyloma, and 12 (4.5%) with undetermined disease status. A maximum MC index of 37.5 was observed in the group with no posterior staphyloma, which was less than the minimum MC index of 42.7 observed in the group with definite posterior staphyloma. The MC index had strong correlations with the axial length and age in eyes with high myopia. CONCLUSIONS: Eyes with posterior staphyloma have a steeper curvature than those with radius 8.44 mm, while eyes without posterior staphyloma do not. MC index 40 (radius 8.44 mm) might act as a reference to distinguish between those with and those without posterior staphyloma.


Assuntos
Miopia Degenerativa , Doenças da Esclera , Humanos , Epitélio Pigmentado da Retina , Rádio (Anatomia) , Estudos Retrospectivos , Estudos Transversais , Miopia Degenerativa/diagnóstico , Tomografia de Coerência Óptica/métodos
17.
BMC Geriatr ; 24(1): 90, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38262951

RESUMO

BACKGROUND: We aimed to evaluate the association of anticholinergic burden and chronic polypharmacy with the incidence of functional decline and all-cause mortality, and to determine the difference between anticholinergic burden and chronic polypharmacy among Korean older people. METHODS: This nationwide cohort study included 42,132 older people aged ≥ 65 years who underwent Korean National Health Insurance Service health examinations from 2007 to 2008. Odds ratios (ORs) and 95% confidence intervals (CIs) for abnormal Timed Up and Go (TUG) test results were assessed using multivariate logistic regression analyses. Hazard ratios (HRs) and 95% CIs for all-cause mortality until the end of 2015 were estimated using multivariable Cox proportional hazards regression analysis. RESULTS: Of the participants, 37.19% had abnormal TUG test results, and 7.66% of those died during the 5.7-year mean follow-up. The abnormal TUG test results OR increased by 27% among individuals with Korean Anticholinergic Burden Scale (KABS) scores ≥ 3 (OR 1.27, 95% CI 1.02-1.58) compared to those with KABS scores of 0. The HRs for all-cause mortality increased for individuals with higher KABS scores (P for trend < 0.001) or chronic polypharmacy (P for trend < 0.001) compared to those for individuals without these conditions. The combination of a higher KABS or chronic polypharmacy and abnormal TUG test results increased the risk of all-cause mortality (All P for trend < 0.001). CONCLUSION: Anticholinergic drug burden shows a better association with functional decline than chronic polypharmacy, and the use of medications and functional decline may be important risk factors for all-cause mortality among older people.


Assuntos
Antagonistas Colinérgicos , Polimedicação , Idoso , Humanos , Antagonistas Colinérgicos/efeitos adversos , Estudos de Coortes , República da Coreia , Estudos Retrospectivos , Mortalidade
18.
Dis Esophagus ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587429

RESUMO

Metabolic dysfunction-associated steatotic liver disease (MASLD) is closely associated with type 2 diabetes and a developing several cancers including esophageal cancer (EC). However, the association between MASLD and EC in diabetic patients has not been investigated. Therefore, we aimed to investigate the relation between MASLD and developing EC in diabetic patients. This was a population-based retrospective cohort study of data from the Korean National Health Insurance Service (NHIS). A total of 1,904,468 subjects diagnosed with diabetes who underwent NHIS-provided health checkups from 2009 to 2012 were included. We constructed a Cox proportional hazard model for the association of fatty liver index (FLI) and the risk of EC stratified by potential confounders. Over a mean follow-up duration of 6.9 years, the incidence of EC was higher in the high (≥60) FLI group compared to the low (<30) FLI group (14.4 vs. 13.7 event per 100,000 person-years). The risk of EC correlated with the degree of FLI, particularly in older (P = 0.002), female (P = 0.033), non-smoking (P = 0.002), and non-drinking patients (P = 0.025). Among obese patients, the risk of EC was not associated with FLI; however, the risk of EC was higher in the high FLI group in non-obese patients. Lean MASLD patients had the highest risk of EC (adjusted hazard ratio 1.78; 95% confidence interval, 1.5-2.13). MASLD was associated with an increased risk of EC in diabetic patients, and lean MASLD has the highest risk. Further studies are required to determine the causal relationship between MASLD and EC.

19.
Sensors (Basel) ; 24(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38894186

RESUMO

Smart wearable sensors are increasingly integrated into everyday life, interfacing with the human body to enable real-time monitoring of biological signals. This study focuses on creating high-sensitivity capacitive-type sensors by impregnating polyester-based 3D spacer fabric with a Carbon Nanotube (CNT) dispersion. The unique properties of conductive particles lead to nonlinear variations in the dielectric constant when pressure is applied, consequently affecting the gauge factor. The results reveal that while the fabric without CNT particles had a gauge factor of 1.967, the inclusion of 0.04 wt% CNT increased it significantly to 5.210. As sensor sensitivity requirements vary according to the application, identifying the necessary CNT wt% is crucial. Artificial intelligence, particularly the Multilayer Perception (MLP) model, enables nonlinear regression analysis for this purpose. The MLP model created and validated in this research showed a high correlation coefficient of 0.99564 between the model predictions and actual target values, indicating its effectiveness and reliability.

20.
Nano Lett ; 23(24): 11526-11532, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38079244

RESUMO

Fe3GaTe2, a recently discovered van der Waals ferromagnet, demonstrates intrinsic ferromagnetism above room temperature, necessitating a comprehensive investigation of the microscopic origins of its high Curie temperature (TC). In this study, we reveal the electronic structure of Fe3GaTe2 in its ferromagnetic ground state using angle-resolved photoemission spectroscopy and density functional theory calculations. Our results establish a consistent correspondence between the measured band structure and theoretical calculations, underscoring the significant contributions of the Heisenberg exchange interaction (Jex) and magnetic anisotropy energy to the development of the high-TC ferromagnetic ordering in Fe3GaTe2. Intriguingly, we observe substantial modifications to these crucial driving factors through doping, which we attribute to alterations in multiple spin-splitting bands near the Fermi level. These findings provide valuable insights into the underlying electronic structure and its correlation with the emergence of high-TC ferromagnetic ordering in Fe3GaTe2.

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