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1.
Cell ; 176(1-2): 127-143.e24, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30633903

RESUMO

DNA damage provokes mutations and cancer and results from external carcinogens or endogenous cellular processes. However, the intrinsic instigators of endogenous DNA damage are poorly understood. Here, we identify proteins that promote endogenous DNA damage when overproduced: the DNA "damage-up" proteins (DDPs). We discover a large network of DDPs in Escherichia coli and deconvolute them into six function clusters, demonstrating DDP mechanisms in three: reactive oxygen increase by transmembrane transporters, chromosome loss by replisome binding, and replication stalling by transcription factors. Their 284 human homologs are over-represented among known cancer drivers, and their RNAs in tumors predict heavy mutagenesis and a poor prognosis. Half of the tested human homologs promote DNA damage and mutation when overproduced in human cells, with DNA damage-elevating mechanisms like those in E. coli. Our work identifies networks of DDPs that provoke endogenous DNA damage and may reveal DNA damage-associated functions of many human known and newly implicated cancer-promoting proteins.


Assuntos
Dano ao DNA/genética , Dano ao DNA/fisiologia , Reparo do DNA/fisiologia , Proteínas de Bactérias/metabolismo , Instabilidade Cromossômica/fisiologia , Replicação do DNA/fisiologia , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/metabolismo , Instabilidade Genômica , Humanos , Proteínas de Membrana Transportadoras/fisiologia , Mutagênese , Mutação , Fatores de Transcrição/metabolismo
2.
Cell ; 150(2): 264-78, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22817890

RESUMO

Most mutations in cancer genomes are thought to be acquired after the initiating event, which may cause genomic instability and drive clonal evolution. However, for acute myeloid leukemia (AML), normal karyotypes are common, and genomic instability is unusual. To better understand clonal evolution in AML, we sequenced the genomes of M3-AML samples with a known initiating event (PML-RARA) versus the genomes of normal karyotype M1-AML samples and the exomes of hematopoietic stem/progenitor cells (HSPCs) from healthy people. Collectively, the data suggest that most of the mutations found in AML genomes are actually random events that occurred in HSPCs before they acquired the initiating mutation; the mutational history of that cell is "captured" as the clone expands. In many cases, only one or two additional, cooperating mutations are needed to generate the malignant founding clone. Cells from the founding clone can acquire additional cooperating mutations, yielding subclones that can contribute to disease progression and/or relapse.


Assuntos
Evolução Clonal , Leucemia Mieloide Aguda/genética , Mutação , Adulto , Idoso , Análise Mutacional de DNA , Progressão da Doença , Feminino , Estudo de Associação Genômica Ampla , Células-Tronco Hematopoéticas/metabolismo , Humanos , Leucemia Mieloide Aguda/fisiopatologia , Masculino , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/genética , Recidiva , Pele/metabolismo , Adulto Jovem
3.
Mol Cell ; 74(4): 785-800.e7, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-30948267

RESUMO

Antibiotics can induce mutations that cause antibiotic resistance. Yet, despite their importance, mechanisms of antibiotic-promoted mutagenesis remain elusive. We report that the fluoroquinolone antibiotic ciprofloxacin (cipro) induces mutations by triggering transient differentiation of a mutant-generating cell subpopulation, using reactive oxygen species (ROS). Cipro-induced DNA breaks activate the Escherichia coli SOS DNA-damage response and error-prone DNA polymerases in all cells. However, mutagenesis is limited to a cell subpopulation in which electron transfer together with SOS induce ROS, which activate the sigma-S (σS) general-stress response, which allows mutagenic DNA-break repair. When sorted, this small σS-response-"on" subpopulation produces most antibiotic cross-resistant mutants. A U.S. Food and Drug Administration (FDA)-approved drug prevents σS induction, specifically inhibiting antibiotic-promoted mutagenesis. Further, SOS-inhibited cell division, which causes multi-chromosome cells, promotes mutagenesis. The data support a model in which within-cell chromosome cooperation together with development of a "gambler" cell subpopulation promote resistance evolution without risking most cells.


Assuntos
Antibacterianos/efeitos adversos , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Mutagênese/genética , Divisão Celular/efeitos dos fármacos , Ciprofloxacina/efeitos adversos , Dano ao DNA/efeitos dos fármacos , DNA Polimerase Dirigida por DNA/genética , Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Mutagênese/efeitos dos fármacos , Mutação , Espécies Reativas de Oxigênio/metabolismo , Resposta SOS em Genética/efeitos dos fármacos , Fator sigma/genética
4.
Mol Cell ; 75(6): 1188-1202.e11, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31399345

RESUMO

The maternal-to-zygotic transition (MZT) is a conserved and fundamental process during which the maternal environment is converted to an environment of embryonic-driven development through dramatic reprogramming. However, how maternally supplied transcripts are dynamically regulated during MZT remains largely unknown. Herein, through genome-wide profiling of RNA 5-methylcytosine (m5C) modification in zebrafish early embryos, we found that m5C-modified maternal mRNAs display higher stability than non-m5C-modified mRNAs during MZT. We discovered that Y-box binding protein 1 (Ybx1) preferentially recognizes m5C-modified mRNAs through π-π interactions with a key residue, Trp45, in Ybx1's cold shock domain (CSD), which plays essential roles in maternal mRNA stability and early embryogenesis of zebrafish. Together with the mRNA stabilizer Pabpc1a, Ybx1 promotes the stability of its target mRNAs in an m5C-dependent manner. Our study demonstrates an unexpected mechanism of RNA m5C-regulated maternal mRNA stabilization during zebrafish MZT, highlighting the critical role of m5C mRNA modification in early development.


Assuntos
5-Metilcitosina/metabolismo , Embrião não Mamífero/embriologia , Desenvolvimento Embrionário/fisiologia , Estabilidade de RNA/fisiologia , RNA Mensageiro Estocado/metabolismo , Peixe-Zebra/embriologia , Animais , Células HeLa , Humanos , Camundongos , RNA Mensageiro Estocado/genética , Peixe-Zebra/genética
5.
J Proteome Res ; 23(1): 500-509, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38097511

RESUMO

Lung cancer is the leading cause of cancer-related death, with high morbidity and mortality rates due to the lack of reliable methods for diagnosing lung cancer at an early stage. Low-dose computed tomography can help detect abnormal areas in the lungs, but only 16% of cases are diagnosed early. Tests for lung cancer markers are often employed to determine genetic expression or mutations in lung carcinogenesis. Serum glycome analysis is a promising new method for early lung cancer diagnosis as glycopatterns exhibit significant differences in lung cancer patients. In this study, we employed a solid-phase chemoenzymatic method to systematically compare glycopatterns in benign cases, adenocarcinoma before and after surgery, and advanced stages of adenocarcinoma. Our findings indicate that serum high-mannose levels are elevated in both benign cases and adenocarcinoma, while complex N-glycans, including fucose and 2,6-linked sialic acid, are downregulated in the serum. Subsequently, we developed an algorithm that utilizes 16 altered N-glycans, 7 upregulated and 9 downregulated, to generate a score based on their intensity. This score can predict the stages of cancer progression in patients through glycan characterization. This methodology offers a potential means of diagnosing lung cancer through serum glycome analysis.


Assuntos
Adenocarcinoma , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Polissacarídeos/metabolismo , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Fucose
6.
Anal Chem ; 96(4): 1498-1505, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38216336

RESUMO

Hydrophilic interaction liquid chromatography (HILIC) is widely used for glycopeptide enrichment in shot-gun glycoproteomics to enhance the glycopeptide signal and minimize the ionization competition of peptides. In this work, we have developed a novel hydrophilic material (glycoHILIC) based on glycopeptides and peptides to provide hydrophilic properties. GlycoHILIC was synthesized by oxidizing cotton and then reacting the resulting aldehyde with the N-terminus of the glycopeptide or peptide by reductive amination. Due to the large amount of hydrophilic carbohydrates and hydrophilic amino acids contained in glycopeptides, glycoHILIC showed significantly better enrichment of glycopeptides than cotton itself. Our results demonstrate that glycoHILIC has high selectivity, a low detection limit, and good stability. Over 257 unique N-linked glycosylation sites in 1477 intact N-glycopeptides from 146 glycoproteins were identified from 1 µL of human serum using glycoHILIC. Serum analysis of pancreatic cancer patients found that 38 N-glycopeptides among 21 glycoproteins changed significantly, of which 7 N-glycopeptides increased and 31 N-glycopeptides decreased. These results demonstrate that glycoHILIC can be used for glycopeptide enrichment and analysis.


Assuntos
Glicopeptídeos , Glicoproteínas , Humanos , Glicopeptídeos/análise , Glicosilação , Cromatografia Líquida/métodos , Interações Hidrofóbicas e Hidrofílicas
7.
Small ; 20(22): e2308851, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38112252

RESUMO

Vanadium oxides have aroused attention as cathode materials in aqueous zinc-ion batteries (AZIBs) due to their low cost and high safety. However, low ion diffusion and vanadium dissolution often lead to capacity decay and deteriorating stability during cycling. Herein, vanadium dioxides (VO2) nanobelts are coated with a single-atom cobalt dispersed N-doped carbon (Co-N-C) layer via a facile calcination strategy to form Co-N-C layer coated VO2 nanobelts (VO2@Co-N-C NBs) for cathodes in AZIBs. Various in-/ex situ characterizations demonstrate the interfaces between VO2 layers and Co-N-C layers can protect the VO2 NBs from collapsing, increase ion diffusion, and enhance the Zn2+ storage performance. Additional density functional theory (DFT) simulations demonstrate that Co─O─V bonds between VO2 and Co-N-C layers can enhance interfacial Zn2+ storage. Moreover, the VO2@Co-N-C NBs provided an ultrahigh capacity (418.7 mAh g-1 at 1 A g-1), outstanding long-term stability (over 8000 cycles at 20 A g-1), and superior rate performance.

8.
J Bioenerg Biomembr ; 56(1): 55-71, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38041751

RESUMO

Circular RNAs (circRNAs) showing unusual expressions have been discovered in pancreatic adenocarcinoma (PAAD). However, the functions and underlying mechanisms of these circRNAs still remain largely unclear. Our current study discovered a notable increase in the expression of circRNA hsa_circ_0002395 (circ_0002395) in both PAAD tissues and cell lines. This up-regulation of circ_0002395 was found to be associated with larger tumor sizes and lymph node metastasis. Furthermore, our findings showed that circ_0002395 facilitated aerobic glycolysis and cell proliferation in PAAD cells by regulating the miR-548c-3p/PDK1 axis. Mechanistically, we identified circ_0002395 as a competing endogenous RNA (ceRNA) that sponged miR-548c-3p, thereby promoting PDK1 expression and aerobic glycolysis, and ultimately resulting in the enhancement of cell proliferation. Our findings found that circ_0002395 promoted proliferation of PAAD cells by enhancing PDK1 expression and aerobic glycolysis by sponging miR-548c-3p.


Assuntos
Adenocarcinoma , MicroRNAs , Neoplasias Pancreáticas , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , Adenocarcinoma/genética , Neoplasias Pancreáticas/genética , Linhagem Celular Tumoral , Proliferação de Células , Glicólise
9.
J Autoimmun ; 142: 103148, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37967495

RESUMO

BACKGROUND: Rheumatoid arthritis (RA) is a chronic autoimmune disorder that affects the joints and produces pain, swelling, and stiffness. It has a lifetime prevalence of up to 1% worldwide. An extract of Tripterygium wilfordii Hook F (TwHF), a member of the Celastraceae herbal family widely available in south China, has been used for treatment of RA since 1960s. METHODS: The current consensus practice guidance (CPG) aims to offer guidance on the application of TwHF in the clinical management of active RA. The CPG followed World Health Organisation (WHO)'s recommended process, carried out three systematic reviews to synthesize data from 19 randomised controlled trials (RCT) involving 1795 participants. We utilized Grading of Recommendations, Assessment, Development and Evaluation (GRADE) to evaluate certainty of evidence and derive recommendations. We rigorously followed The Appraisal of Guidelines for Research and Evaluation II (AGREE II) as conduct guides to minimise bias and promote transparency. RESULTS: There was no obvious difference between TwHF monotherapy and methotrexate (MTX) monotherapy on ACR20 (RCT = 2, N = 390, RR = 1.06, 95%CI 0.90-1.26, moderate certainty), ACR50 (RCT = 3, N = 419, RR = 1.03, 95%CI 0.80-1.34, moderate certainty), ACR70 (RCT = 2, N = 390, RR = 1.12, 95%CI 0.69-1.79, low certainty). TwHF monotherapy may be better than salicylazosulfapyridine monotherapy on ACR20 and the effect may be similar on ACR50 and ACR70. Seven RCTs compared MTX combined with TwHF versus MTX monotherapy, and the meta-analysis results favoured combination therapy group on ACR20 (RCT = 3, N = 470, RR = 1.44, 95%CI 1.28-1.62, moderate certainty), ACR50 (RCT = 4, N = 500, RR = 1.88, 95%CI 1.56-2.28, moderate certainty) and ACR70 (RCT = 2, N = 390, RR = 2.12, 95%CI 1.40-3.19, low certainty). We found no obvious difference between groups on critical safety outcomes, including infection (RCT = 3, N = 493, RR = 1.37, 95%CI 0.84-2.23), liver dysfunction (RCT = 5, N = 643, RR = 1.14, 95%CI 0.71-1.85), renal damage (RCT = 3, N = 450, RR = 2.20, 95%CI 0.50-9.72). CONCLUSION: Upon full review of the evidence, the guidance panel reached consensus on recommendations for the use of TwHF in people with active RA, either as monotherapy or as combination therapy with MTX.


Assuntos
Antirreumáticos , Artrite Reumatoide , Humanos , Antirreumáticos/uso terapêutico , Tripterygium , Consenso , Artrite Reumatoide/tratamento farmacológico , Metotrexato/uso terapêutico , Doença Crônica
10.
Blood ; 140(14): 1607-1620, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-35675516

RESUMO

Hematopoietic stem/progenitor cells (HSPCs) reside in localized microenvironments, or niches, in the bone marrow that provide key signals regulating their activity. A fundamental property of hematopoiesis is the ability to respond to environmental cues such as inflammation. How these cues are transmitted to HSPCs within hematopoietic niches is not well established. Here, we show that perivascular bone marrow dendritic cells (DCs) express a high basal level of Toll-like receptor-1 (TLR1) and TLR2. Systemic treatment with a TLR1/2 agonist induces HSPC expansion and mobilization. It also induces marked alterations in the bone marrow microenvironment, including a decrease in osteoblast activity and sinusoidal endothelial cell numbers. TLR1/2 agonist treatment of mice in which Myd88 is deleted specifically in DCs using Zbtb46-Cre show that the TLR1/2-induced expansion of multipotent HPSCs, but not HSPC mobilization or alterations in the bone marrow microenvironment, is dependent on TLR1/2 signaling in DCs. Interleukin-1ß (IL-1ß) is constitutively expressed in both murine and human DCs and is further induced after TLR1/2 stimulation. Systemic TLR1/2 agonist treatment of Il1r1-/- mice show that TLR1/2-induced HSPC expansion is dependent on IL-1ß signaling. Single-cell RNA-sequencing of low-risk myelodysplastic syndrome bone marrow revealed that IL1B and TLR1 expression is increased in DCs. Collectively, these data suggest a model in which TLR1/2 stimulation of DCs induces secretion of IL-1ß and other inflammatory cytokines into the perivascular niche, which in turn, regulates multipotent HSPCs. Increased DC TLR1/2 signaling may contribute to altered HSPC function in myelodysplastic syndrome by increasing local IL-1ß expression.


Assuntos
Células da Medula Óssea , Células Dendríticas , Células-Tronco Hematopoéticas , Interleucina-1beta , Síndromes Mielodisplásicas , Animais , Medula Óssea/metabolismo , Células da Medula Óssea/citologia , Citocinas/metabolismo , Células Dendríticas/citologia , Células-Tronco Hematopoéticas/citologia , Humanos , Interleucina-1beta/metabolismo , Camundongos , Síndromes Mielodisplásicas/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , RNA/metabolismo , Receptor 1 Toll-Like/metabolismo , Receptor 2 Toll-Like/agonistas , Receptor 2 Toll-Like/metabolismo
11.
Anal Biochem ; 685: 115388, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-37967783

RESUMO

The retrospective detection of organophosphorus nerve agents (OPNAs) exposure has been achieved by the off-site analysis of OPNA-human serum albumin (HSA) adducts using mass spectrometry-based detection approaches. However, few specific methods are accessible for on-site detection. To address this, a novel immunofluorescence microfluidic chip (IFMC) testing system combining europium chelated microparticle (EuCM) with self-driven microfluidic chip assay has been established to unambiguously determine soman (GD) and VX exposure within 20 min, respectively. The detection system was based on the principle of indirect competitive enzyme-linked immunosorbent assay. The specific monoclonal antibodies that respectively recognized the phosphonylated tyrosine 411 of GD-HSA and VX-HSA adducts were labeled by EuCM to capture corresponding adducts in the exposed samples. The phosphonylated peptides in the test line and goat-anti-rabbit antibody in the control line were utilized to bind the EuCM-labeled antibodies for signal exhibition. The developed IFMC chip could discriminatively detect exposed HSA adducts with high specificity, demonstrating a low limit of detection at exposure concentrations of 0.5 × 10-6 mol/L VX and 1.0 × 10-6 mol/L GD. The exposed serum samples can be qualitatively detected following an additional pretreatment procedure. This is a novel rapid detection system capable of discriminating GD and VX exposure, providing an alternative method for rapidly identifying OPNA exposure.


Assuntos
Soman , Animais , Humanos , Coelhos , Soman/metabolismo , Európio , Microfluídica , Estudos Retrospectivos , Albumina Sérica Humana , Imunofluorescência
12.
Cell Commun Signal ; 22(1): 146, 2024 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388414

RESUMO

Paraquat (PQ) is an irreplaceable insecticide in many countries for the advantage of fast-acting and broad-spectrum. However, PQ was classified as the most prevailing poisoning substance for suicide with no specific antidote. Therefore, it is imperative to develop more effective therapeutic agents for the treatment of PQ poisoning. In the present study, both the RNA-Seq and the application of various cell death inhibitors reflected that ferroptosis exerts a crucial regulatory role in PQ poisoning. Moreover, we found PQ strengthens lipid peroxidation as evidenced by different experimental approaches. Of note, pretreatment of iron chelation agent DFO could ameliorate the ferroptotic cell death and alleviate the ferroptosis-related events. Mechanistically, PQ treatment intensively impaired mitochondrial homeostasis, enhanced phosphorylation of AMPK, accelerated the autophagy flux and triggered the activation of Nuclear receptor coactivator 4-ferritin heavy chain (NCOA4-FTH) axis. Importantly, the activation of autophagy was observed prior to the degradation of ferritin, and inhibition of autophagy could inhibit the accumulation of iron caused by the ferritinophagy process. Genetic and pharmacological inhibition of ferritinophagy could alleviate the lethal oxidative events, and rescue the ferroptotic cell death. Excitingly, in the mouse models of PQ poisoning, both the administration of DFO and adeno-associated virus-mediated FTH overexpression significantly reduced PQ-induced ferroptosis and improved the pathological characteristics of pulmonary fibrosis. In summary, the current work provides an in-depth study on the mechanism of PQ intoxication, describes a framework for the further understanding of ferroptosis in PQ-associated biological processes, and demonstrates modulation of iron metabolism may act as a promising therapeutic agent for the management of PQ toxicity.


Assuntos
Ferroptose , Lesão Pulmonar , Animais , Humanos , Camundongos , Autofagia , Ferritinas/metabolismo , Ferritinas/farmacologia , Ferro/metabolismo , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/tratamento farmacológico , Coativadores de Receptor Nuclear/metabolismo , Paraquat/toxicidade , Fatores de Transcrição/metabolismo
13.
Anesthesiology ; 140(1): 102-115, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37812765

RESUMO

BACKGROUND: Multiple neural structures involved in maintaining wakefulness have been found to promote arousal from general anesthesia. The medial septum is a critical region that modulates arousal behavior. This study hypothesized that glutamatergic neurons in the medial septum play a crucial role in regulating states of consciousness during sevoflurane general anesthesia. METHODS: Adult male mice were used in this study. The effects of sevoflurane anesthesia on neuronal activity were determined by fiber photometry. Lesions and chemogenetic manipulations were used to study the effects of the altered activity of medial septal glutamatergic neurons on anesthesia induction, emergence, and sensitivity to sevoflurane. Optogenetic stimulation was used to observe the role of acute activation of medial septal glutamatergic neurons on cortical activity and behavioral changes during sevoflurane-induced continuous steady state of general anesthesia and burst suppression state. RESULTS: The authors found that medial septal glutamatergic neuronal activity decreased during sevoflurane anesthesia induction and recovered in the early period of emergence. Chemogenetic activation of medial septal glutamatergic neurons prolonged the induction time (mean ± SD, hM3Dq-clozapine N-oxide vs. hM3Dq-saline, 297.5 ± 60.1 s vs. 229.4 ± 29.9 s, P < 0.001, n = 11) and decreased the emergence time (53.2 ± 11.8 s vs. 77.5 ± 33.5 s, P = 0.025, n = 11). Lesions or chemogenetic inhibition of these neurons produced the opposite effects. During steady state of general anesthesia and deep anesthesia-induced burst suppression state, acute optogenetic activation of medial septal glutamatergic neurons induced cortical activation and behavioral emergence. CONCLUSIONS: The study findings reveal that activation of medial septal glutamatergic neurons has arousal-promoting effects during sevoflurane anesthesia in male mice. The activation of these neurons prolongs the induction and accelerates the emergence of anesthesia.


Assuntos
Estado de Consciência , Neurônios , Camundongos , Animais , Masculino , Sevoflurano/farmacologia , Vigília/fisiologia , Anestesia Geral
14.
Eur Radiol ; 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38175218

RESUMO

OBJECTIVES: This study aimed to examine the equivalence of computed tomography (CT)-based synthetic T1-weighted imaging (T1WI) to conventional T1WI for the quantitative assessment of brain morphology. MATERIALS AND METHODS: This prospective study examined 35 adult patients undergoing brain magnetic resonance imaging (MRI) and CT scans. An image synthesis method based on a deep learning model was used to generate synthetic T1WI (sT1WI) from CT data. Two senior radiologists used sT1WI and conventional T1WI on separate occasions to independently measure clinically relevant brain morphological parameters. The reliability and consistency between conventional and synthetic T1WI were assessed using statistical consistency checks, comprising intra-reader, inter-reader, and inter-method agreement. RESULTS: The intra-reader, inter-reader, and inter-method reliability and variability mostly exhibited the desired performance, except for several poor agreements due to measurement differences between the radiologists. All the measurements of sT1WI were equivalent to that of T1WI at 5% equivalent intervals. CONCLUSION: This study demonstrated the equivalence of CT-based sT1WI to conventional T1WI for quantitatively assessing brain morphology, thereby providing more information on imaging diagnosis with a single CT scan. CLINICAL RELEVANCE STATEMENT: Real-time synthesis of MR images from CT scans reduces the time required to acquire MR signals, improving the efficiency of the treatment planning system and providing benefits in the clinical diagnosis of patients with contraindications such as presence of metal implants or claustrophobia. KEY POINTS: • Deep learning-based image synthesis methods generate synthetic T1-weighted imaging from CT scans. • The equivalence of synthetic T1-weighted imaging and conventional MRI for quantitative brain assessment was investigated. • Synthetic T1-weighted imaging can provide more information per scan and be used in preoperative diagnosis and radiotherapy.

15.
BMC Neurol ; 24(1): 246, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014305

RESUMO

BACKGROUND: To investigate the association between white matter changes and ventricular expansion in idiopathic normal pressure hydrocephalus (iNPH) based on diffusion spectrum imaging (DSI). METHODS: We included 32 patients with iNPH who underwent DSI using a 3T MRI scanner. The lateral ventricles were manually segmented, and ventricular volumes were measured. Two methods were utilised in the study: manual region-of-interest (ROI) delineation and tract diffusion profile analysis. General fractional anisotropy (GFA) and fractional anisotropy (FA) were extracted in different white matter regions, including the bilateral internal capsule (anterior and posterior limbs) and corpus callosum (body, genu, and splenium) with manual ROI delineation. The 18 main tracts in the brain of each patient were extracted; the diffusion metrics of 100 equidistant nodes on each fibre were calculated, and Spearman's correlation coefficient was used to determine the correlation between diffusion measures and ventricular volume of iNPH patients. RESULTS: The GFA and FA of all ROI showed no significant correlation with lateral ventricular volume. However, in the tract diffusion profile analysis, lateral ventricular volume was positively correlated with part of the cingulum bundle, left corticospinal tract, and bilateral thalamic radiation posterior, whereas it was negatively correlated with the bilateral cingulum parahippocampal (all p < 0.05). CONCLUSIONS: The effect of ventricular enlargement in iNPH on some white matter fibre tracts around the ventricles was limited and polarizing, and most white matter fibre tract integrity changes were not associated with ventricular enlargement; this reflects that multiple pathological mechanisms may have been combined to cause white matter alterations in iNPH.


Assuntos
Hidrocefalia de Pressão Normal , Substância Branca , Humanos , Hidrocefalia de Pressão Normal/diagnóstico por imagem , Hidrocefalia de Pressão Normal/patologia , Masculino , Feminino , Idoso , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Idoso de 80 Anos ou mais , Imagem de Tensor de Difusão/métodos , Pessoa de Meia-Idade , Imagem de Difusão por Ressonância Magnética/métodos , Ventrículos Cerebrais/diagnóstico por imagem , Ventrículos Cerebrais/patologia , Anisotropia
16.
Environ Res ; 252(Pt 4): 119145, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38754610

RESUMO

The impact of CO2 fertilization on enhancing global forest gross primary productivity (GPP) is acknowledged, but its interaction with climate factors-air temperature (Tem), precipitation (Pre), vapor pressure deficit (VPD), and radiation (Rad)-remains unclear. In this study, global forest GPP trends from 1982 to 2018 were examined using BEPS, NIRv, FLUXCOM, and revised EC-LUE datasets, with interannual trends of 5.618 (p < 0.01), 5.831 (p < 0.01), 0.227, and 6.566 g C m-2 yr-1 (p < 0.01), respectively. Elevated CO2 was identified as the primary driver of GPP trends, with the dominant area ranging from 51.11% to 90.37% across different GPP datasets. In the NIRv and revised EC-LUE datasets, the positive impact of CO2 on GPP showed a decrease of 0.222 g C m-2 yr-1, while the negative impact of Rad increased by 0.007 g C m-2 yr-1. An inhibitory relationship was found between the actual effects of elevated CO2 and climate change on GPP in most forest types. At lower latitudes, Tem primarily constrained CO2 fertilization, while at higher latitudes, VPD emerged as the key limiting factor. This was mainly attributed to the potential trade-off or competition between elevated CO2 and climate change in influencing GPP, with strategic resource allocation varying across different forest ecosystems. This study highlights the significant inhibitory effects of elevated CO2 and climate change on global forest GPP, providing insights into the dynamic responses of forest ecosystems to changing environments.


Assuntos
Dióxido de Carbono , Mudança Climática , Florestas , Dióxido de Carbono/análise , Árvores
17.
Artigo em Inglês | MEDLINE | ID: mdl-38719166

RESUMO

OBJECTIVE: To investigate the effects of physiotherapeutic scoliosis-specific exercises (PSSE) on coronal, horizontal, and sagittal deformities of the spine in adolescent idiopathic scoliosis (AIS) as well as how curve severity, intervention duration, and intervention type could modify these effects. DATA SOURCES: Data sources included PubMed, Web of Science, Embase, Cochrane Library, and Scopus databases, which were searched from their inception to September 5, 2023. STUDY SELECTION: Clinical controlled trials reporting the effects of PSSE on the Cobb angle, angle of trunk rotation (ATR), thoracic kyphosis (TK), or lumbar lordosis in patients with AIS aged 10-18 years. The experimental groups received PSSE; the control groups received standard care (observation or bracing) or conventional exercise such as core stabilization exercise, Pilates, proprioceptive neuromuscular facilitation, and other nonspecific exercises. DATA EXTRACTION: Two researchers independently extracted key information from eligible studies. The quality of the studies was assessed using the Cochrane Handbook version 5.1.0 risk of bias assessment and the JBI Center for Evidence-Based Health Care (2016) of quasi-experimental research authenticity assessment tool. The level and certainty of evidence were rated according to the Grading of Recommendations, Assessment, Development, and Evaluation framework. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The protocol for this study was registered in PROSPERO (CRD42023404996). DATA SYNTHESIS: Twelve randomized controlled trials (RCTs) and 5 non-RCTs were meta-analyzed separately. The results indicated that compared with other nonsurgical management, PSSE significantly improved the Cobb angle, ATR, and TK, whereas the lumbar lordosis improvement was not statistically significant. Additionally, the efficacy of PSSE on Cobb angle was not significant in patients with curve severity ≥30° compared with controls. Nevertheless, the pooled effect of PSSE on Cobb angle was not significantly modified by intervention duration and intervention type and that on ATR was not significantly modified by intervention duration. The overall quality of evidence according to Grading of Recommendations, Assessment, Development, and Evaluation was moderate to low for RCT and very low for non-RCT. CONCLUSIONS: PSSE exhibited positive benefits on the Cobb angle, ATR, and TK in patients with AIS compared with other nonsurgical therapies. In addition, the effectiveness of PSSE may be independent of intervention duration and intervention type but may be influenced by the initial Cobb angle. However, more RCTs are needed in the future to validate the efficacy of PSSE in moderate AIS with a mean Cobb angle ≥30°. Current evidence is limited by inconsistent control group interventions and small sample size of the studies.

18.
BMC Med Imaging ; 24(1): 91, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627678

RESUMO

BACKGROUND: The relationship between the biological pathways related to deep learning radiomics (DLR) and lymph node metastasis (LNM) of breast cancer is still poorly understood. This study explored the value of DLR based on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in LNM of invasive breast cancer. It also analyzed the biological significance of DLR phenotype based on genomics. METHODS: Two cohorts from the Cancer Imaging Archive project were used, one as the training cohort (TCGA-Breast, n = 88) and one as the validation cohort (Breast-MRI-NACT Pilot, n = 57). Radiomics and deep learning features were extracted from preoperative DCE-MRI. After dual selection by principal components analysis (PCA) and relief methods, radiomics and deep learning models for predicting LNM were constructed by the random forest (RF) method. A post-fusion strategy was used to construct the DLR nomograms (DLRNs) for predicting LNM. The performance of the models was evaluated using the receiver operating characteristic (ROC) curve and Delong test. In the training cohort, transcriptome data were downloaded from the UCSC Xena online database, and biological pathways related to the DLR phenotypes were identified. Finally, hub genes were identified to obtain DLR gene expression (RadDeepGene) scores. RESULTS: DLRNs were based on area under curve (AUC) evaluation (training cohort, AUC = 0.98; validation cohort, AUC = 0.87), which were higher than single radiomics models or GoogLeNet models. The Delong test (radiomics model, P = 0.04; GoogLeNet model, P = 0.01) also validated the above results in the training cohorts, but they were not statistically significant in the validation cohort. The GoogLeNet phenotypes were related to multiple classical tumor signaling pathways, characterizing the biological significance of immune response, signal transduction, and cell death. In all, 20 genes related to GoogLeNet phenotypes were identified, and the RadDeepGene score represented a high risk of LNM (odd ratio = 164.00, P < 0.001). CONCLUSIONS: DLRNs combining radiomics and deep learning features of DCE-MRI images improved the preoperative prediction of LNM in breast cancer, and the potential biological characteristics of DLRN were identified through genomics.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Segunda Neoplasia Primária , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/genética , Radiômica , Metástase Linfática/diagnóstico por imagem , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Linfonodos
19.
Lasers Surg Med ; 56(4): 346-354, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38462706

RESUMO

OBJECTIVES: Public's interest in noninvasive skin rejuvenation treatments continues to grow. The advantage of combination therapy lies in that it can target different aspects of skin rejuvenation. This study aimed to assess the efficacy and safety of microfocused ultrasound (MFU) combined with delicate pulsed light (DPL) for facial rejuvenation. METHODS: Twenty-one patients with facial relaxation were enrolled. All patients received whole-face MFU treatment, and one side of the face was randomly assigned to receive DPL. MFU treatment was performed at Months 0 and 3, while DPL treatment was performed at Months 1, 2, 4, and 5. The length and angle of the nasolabial fold and perioral wrinkles, melanin index (MI), erythema index (EI), transepidermal water loss (TEWL), and follow-up time were recorded at Months 0, 3, and 6. Side effects were recorded during treatment and each follow-up visit. RESULTS: Twenty patients successfully completed the study. At the sixth month, the average length of perioral wrinkles and nasolabial folds on the combined side decreased by 11.5% (pwithin < 0.001) and 6.5% (pwithin = 0.011), while 8.3% (pwithin = 0.012) and 3.8% (pwithin = 0.02) on the MFU side. Compared with MFU treatment alone, the combined treatment also showed significant improvements in nasolabial fold angle (from 28.8 ± 3.4° to 32.7 ± 5.0°) and perioral wrinkle angle (from 39.3 ± 5.0° to 43.7 ± 5.1°). In addition, the combined side had greater benefits than the MFU side in improving MI, EI, TEWL, and skin elasticity (pbetween < 0.05). Except for one patient who withdrew due to increased skin sensitivity after MFU treatment, other subjects did not experience permanent or serious side effects. CONCLUSIONS: The combination of MFU and DPL for facial rejuvenation treatment is safe and effective. The combined treatment has better efficacy in skin firmness, and improving skin tone.


Assuntos
Técnicas Cosméticas , Envelhecimento da Pele , Humanos , Rejuvenescimento , Estudos Prospectivos , Pele , Ultrassonografia , Eritema , Resultado do Tratamento , Satisfação do Paciente
20.
Acta Radiol ; 65(1): 41-48, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37071506

RESUMO

BACKGROUND: Computed tomography (CT) and magnetic resonance imaging (MRI) are indicated for use in preoperative planning and may complicate diagnosis and place a burden on patients with lumbar disc herniation. PURPOSE: To investigate the diagnostic potential of MRI-based synthetic CT with conventional CT in the diagnosis of lumbar disc herniation. MATERIAL AND METHODS: After obtaining prior institutional review board approval, 19 patients who underwent conventional and synthetic CT imaging were enrolled in this prospective study. Synthetic CT images were generated from the MRI data using U-net. The two sets of images were compared and analyzed qualitatively by two musculoskeletal radiologists. The images were rated on a 4-point scale to determine their subjective quality. The agreement between the conventional and synthetic images for a diagnosis of lumbar disc herniation was determined independently using the kappa statistic. The diagnostic performances of conventional and synthetic CT images were evaluated for sensitivity, specificity, and accuracy, and the consensual results based on T2-weighted imaging were employed as the reference standard. RESULTS: The inter-reader and intra-reader agreement were almost moderate for all evaluated modalities (κ = 0.57-0.79 and 0.47-0.75, respectively). The sensitivity, specificity, and accuracy for detecting lumbar disc herniation were similar for synthetic and conventional CT images (synthetic vs. conventional, reader 1: sensitivity = 91% vs. 81%, specificity = 83% vs. 100%, accuracy = 87% vs. 91%; P < 0.001; reader 2: sensitivity = 84% vs. 81%, specificity = 85% vs. 98%, accuracy = 84% vs. 90%; P < 0.001). CONCLUSION: Synthetic CT images can be used in the diagnostics of lumbar disc herniation.


Assuntos
Deslocamento do Disco Intervertebral , Humanos , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Estudos Prospectivos , Estudos de Viabilidade , Vértebras Lombares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Imageamento por Ressonância Magnética/métodos
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