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Plant roots encounter numerous pathogenic microbes that often cause devastating diseases. One such pathogen, Plasmodiophora brassicae (Pb), causes clubroot disease and severe yield losses on cruciferous crops worldwide. Here, we report the isolation and characterization of WeiTsing (WTS), a broad-spectrum clubroot resistance gene from Arabidopsis. WTS is transcriptionally activated in the pericycle upon Pb infection to prevent pathogen colonization in the stele. Brassica napus carrying the WTS transgene displayed strong resistance to Pb. WTS encodes a small protein localized in the endoplasmic reticulum (ER), and its expression in plants induces immune responses. The cryoelectron microscopy (cryo-EM) structure of WTS revealed a previously unknown pentameric architecture with a central pore. Electrophysiology analyses demonstrated that WTS is a calcium-permeable cation-selective channel. Structure-guided mutagenesis indicated that channel activity is strictly required for triggering defenses. The findings uncover an ion channel analogous to resistosomes that triggers immune signaling in the pericycle.
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Brassica napus , Plasmodioforídeos , Microscopia Crioeletrônica , Chumbo , Brassica napus/genética , Plasmodioforídeos/fisiologia , Canais Iônicos , Doenças das PlantasRESUMO
Nucleotide-binding, leucine-rich repeat receptors (NLRs) are major immune receptors in plants and animals. Upon activation, the Arabidopsis NLR protein ZAR1 forms a pentameric resistosome in vitro and triggers immune responses and cell death in plants. In this study, we employed single-molecule imaging to show that the activated ZAR1 protein can form pentameric complexes in the plasma membrane. The ZAR1 resistosome displayed ion channel activity in Xenopus oocytes in a manner dependent on a conserved acidic residue Glu11 situated in the channel pore. Pre-assembled ZAR1 resistosome was readily incorporated into planar lipid-bilayers and displayed calcium-permeable cation-selective channel activity. Furthermore, we show that activation of ZAR1 in the plant cell led to Glu11-dependent Ca2+ influx, perturbation of subcellular structures, production of reactive oxygen species, and cell death. The results thus support that the ZAR1 resistosome acts as a calcium-permeable cation channel to trigger immunity and cell death.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Arabidopsis/metabolismo , Cálcio/metabolismo , Proteínas de Transporte/metabolismo , Resistência à Doença/imunologia , Imunidade Vegetal , Transdução de Sinais , Animais , Morte Celular , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular , Ácido Glutâmico/metabolismo , Bicamadas Lipídicas/metabolismo , Oócitos/metabolismo , Células Vegetais/metabolismo , Multimerização Proteica , Protoplastos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Imagem Individual de Molécula , Vacúolos/metabolismo , XenopusRESUMO
Stomata in leaves regulate gas (carbon dioxide and water vapor) exchange and water transpiration between plants and the atmosphere. SLow Anion Channel 1 (SLAC1) mediates anion efflux from guard cells and plays a crucial role in controlling stomatal aperture. It serves as a central hub for multiple signaling pathways in response to environmental stimuli, with its activity regulated through phosphorylation via various plant protein kinases. However, the molecular mechanism underlying SLAC1 phosphoactivation has remained elusive. Through a combination of protein sequence analyses, AlphaFold-based modeling and electrophysiological studies, we unveiled that the highly conserved motifs on the N- and C-terminal segments of SLAC1 form a cytosolic regulatory domain (CRD) that interacts with the transmembrane domain(TMD), thereby maintaining the channel in an autoinhibited state. Mutations in these conserved motifs destabilize the CRD, releasing autoinhibition in SLAC1 and enabling its transition into an activated state. Our further studies demonstrated that SLAC1 activation undergoes an autoinhibition-release process and subsequent structural changes in the pore helices. These findings provide mechanistic insights into the activation mechanism of SLAC1 and shed light on understanding how SLAC1 controls stomatal closure in response to environmental stimuli.
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Proteínas de Arabidopsis , Arabidopsis , Estômatos de Plantas , Transdução de Sinais , Fosforilação , Estômatos de Plantas/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Domínios Proteicos , MutaçãoRESUMO
ABSTRACT: Chronic active Epstein-Barr virus (EBV) disease (CAEBV) is a lethal syndrome because of persistent EBV infection. When diagnosed as CAEBV, EBV infection was observed in multiple hematopoietic lineages, but the etiology of CAEBV is still elusive. Bone marrow and peripheral cells derived from 5 patients with CAEBV, 1 patient with EBV-associated hemophagocytic lymphohistiocytosis, and 2 healthy controls were analyzed. Multiple assays were applied to identify and characterize EBV-infected cells, including quantitative polymerase chain reaction, PrimeFlow, and single-cell RNA-sequencing (scRNA-seq). Based on scRNA-seq data, alterations in gene expression of particular cell types were analyzed between patients with CAEBV and controls, and between infected and uninfected cells. One patient with CAEBV was treated with allogeneic hematopoietic stem cell transplantation (HSCT), and the samples derived from this patient were analyzed again 6 months after HSCT. EBV infected the full spectrum of the hematopoietic system including both lymphoid and myeloid lineages, as well as the hematopoietic stem cells (HSCs) of the patients with CAEBV. EBV-infected HSCs exhibited a higher differentiation rate toward downstream lineages, and the EBV infection had an impact on both the innate and adaptive immunity, resulting in inflammatory symptoms. EBV-infected cells were thoroughly removed from the hematopoietic system after HSCT. Taken together, multiple lines of evidence presented in this study suggest that CAEBV disease originates from the infected HSCs, which might potentially lead to innovative therapy strategies for CAEBV.
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Infecções por Vírus Epstein-Barr , Linfo-Histiocitose Hemofagocítica , Humanos , Herpesvirus Humano 4/genética , Doença Crônica , Linfo-Histiocitose Hemofagocítica/complicações , Células-Tronco HematopoéticasRESUMO
Noninvasive control of neuronal activity in the deep brain can be illuminating for probing brain function and treating dysfunctions. Here, we present a sonogenetic approach for controlling distinct mouse behavior with circuit specificity and subsecond temporal resolution. Targeted neurons in subcortical regions were made to express a mutant large conductance mechanosensitive ion channel (MscL-G22S), enabling ultrasound to trigger activity in MscL-expressing neurons in the dorsal striatum and increase locomotion in freely moving mice. Ultrasound stimulation of MscL-expressing neurons in the ventral tegmental area could activate the mesolimbic pathway to trigger dopamine release in the nucleus accumbens and modulate appetitive conditioning. Moreover, sonogenetic stimulation of the subthalamic nuclei of Parkinson's disease model mice improved their motor coordination and mobile time. Neuronal responses to ultrasound pulse trains were rapid, reversible, and repeatable. We also confirmed that the MscL-G22S mutant is more effective to sensitize neurons to ultrasound compared to the wild-type MscL. Altogether, we lay out a sonogenetic approach which can selectively manipulate targeted cells to activate defined neural pathways, affect specific behaviors, and relieve symptoms of neurodegenerative disease.
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Doenças Neurodegenerativas , Núcleo Subtalâmico , Camundongos , Animais , Encéfalo , Núcleo Subtalâmico/fisiologia , Núcleo Accumbens , Dopamina/fisiologia , Vias NeuraisRESUMO
The subiculum is positioned at a critical juncture at the interface of the hippocampus with the rest of the brain. However, the exact roles of the subiculum in most hippocampal-dependent memory tasks remain largely unknown. One obstacle to make comparisons of neural firing patterns between the subiculum and hippocampus is the broad firing fields of the subicular cells. Here, we used spiking phases in relation to theta rhythm to parse the broad firing field of a subicular neuron into multiple subfields to find the unique functional contribution of the subiculum while male rats performed a hippocampal-dependent visual scene memory task. Some of the broad firing fields of the subicular neurons were successfully divided into multiple subfields similar to those in the CA1 by using the theta phase precession cycle. The new paradigm significantly improved the detection of task-relevant information in subicular cells without affecting the information content represented by CA1 cells. Notably, we found that multiple fields of a single subicular neuron, unlike those in the CA1, carried heterogeneous task-related information such as visual context and choice response. Our findings suggest that the subicular cells integrate multiple task-related factors by using theta rhythm to associate environmental context with action.
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Potenciais de Ação/fisiologia , Região CA1 Hipocampal/fisiologia , Memória/fisiologia , Neurônios/fisiologia , Ritmo Teta/fisiologia , Algoritmos , Animais , Região CA1 Hipocampal/anatomia & histologia , Masculino , Aprendizagem em Labirinto/fisiologia , Neurônios/citologia , Reconhecimento Visual de Modelos/fisiologia , Ratos , Ratos Long-EvansRESUMO
Proneural genes play a crucial role in neuronal differentiation. However, our understanding of the regulatory mechanisms governing proneural genes during neuronal differentiation remains limited. RFX4, identified as a candidate regulator of proneural genes, has been reported to be associated with the development of neuropsychiatric disorders. To uncover the regulatory relationship, we utilized a combination of multi-omics data, including ATAC-seq, ChIP-seq, Hi-C, and RNA-seq, to identify RFX4 as an upstream regulator of proneural genes. We further validated the role of RFX4 using an in vitro model of neuronal differentiation with RFX4 knock-in and a CRISPR-Cas9 knock-out system. As a result, we found that RFX4 directly interacts with the promoters of POU3F2 and NEUROD1. Transcriptomic analysis revealed a set of genes associated with neuronal development, which are highly implicated in the development of neuropsychiatric disorders, including schizophrenia. Notably, ectopic expression of RFX4 can drive human embryonic stem cells toward a neuronal fate. Our results strongly indicate that RFX4 serves as a direct upstream regulator of proneural genes, a role that is essential for normal neuronal development. Impairments in RFX4 function could potentially be related to the development of various neuropsychiatric disorders. However, understanding the precise mechanisms by which the RFX4 gene influences the onset of neuropsychiatric disorders requires further investigation through human genetic studies.
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Fatores de Transcrição Hélice-Alça-Hélice Básicos , Proteínas de Homeodomínio , Neurônios , Fatores do Domínio POU , Fatores de Transcrição de Fator Regulador X , Humanos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Perfilação da Expressão Gênica , Regiões Promotoras Genéticas , RNA-Seq , Diferenciação Celular , Proteínas de Homeodomínio/genética , Fatores do Domínio POU/genética , Fatores de Transcrição de Fator Regulador X/genéticaRESUMO
In σ-dependent transcriptional pausing, the transcription initiation factor σ, translocating with RNA polymerase (RNAP), makes sequence-specific proteinDNA interactions with a promoter-like sequence element in the transcribed region, inducing pausing. It has been proposed that, in σ-dependent pausing, the RNAP active center can access off-pathway "backtracked" states that are substrates for the transcript-cleavage factors of the Gre family and on-pathway "scrunched" states that mediate pause escape. Here, using site-specific proteinDNA photocrosslinking to define positions of the RNAP trailing and leading edges and of σ relative to DNA at the λPR' promoter, we show directly that σ-dependent pausing in the absence of GreB in vitro predominantly involves a state backtracked by 24 bp, and σ-dependent pausing in the presence of GreB in vitro and in vivo predominantly involves a state scrunched by 23 bp. Analogous experiments with a library of 47 (â¼16,000) transcribed-region sequences show that the state scrunched by 23 bpand only that stateis associated with the consensus sequence, T−3N−2Y−1G+1, (where −1 corresponds to the position of the RNA 3' end), which is identical to the consensus for pausing in initial transcription and which is related to the consensus for pausing in transcription elongation. Experiments with heteroduplex templates show that sequence information at position T−3 resides in the DNA nontemplate strand. A cryoelectron microscopy structure of a complex engaged in σ-dependent pausing reveals positions of DNA scrunching on the DNA nontemplate and template strands and suggests that position T−3 of the consensus sequence exerts its effects by facilitating scrunching.
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RNA Polimerases Dirigidas por DNA , Transcrição Gênica , Microscopia Crioeletrônica , DNA , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/genéticaRESUMO
Cep57, a vital centrosome-associated protein, recruits essential regulatory enzymes for centriole duplication. Its dysfunction leads to anomalies, including reduced centrioles and mosaic-variegated aneuploidy syndrome. Despite functional investigations, understanding structural aspects and their correlation with functions is partial till date. We present the structure of human Cep57 C-terminal microtubule binding (MT-BD) domain, revealing conserved motifs ensuring functional preservation across evolution. A leucine zipper, with an adjacent possible microtubule-binding region, potentially forms a stabilizing scaffold for microtubule nucleation-accommodating pulling and tension from growing microtubules. This study highlights conserved structural features of Cep57 protein, compares them with other analogous proteins, and explores how protein function is maintained across diverse organisms.
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Proteínas de Ciclo Celular , Zíper de Leucina , Microtúbulos , Ligação Proteica , Humanos , Microtúbulos/metabolismo , Microtúbulos/química , Cristalografia por Raios X , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Modelos Moleculares , Sítios de Ligação , Proteínas Associadas aos Microtúbulos/química , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Sequência de Aminoácidos , Domínios Proteicos , Proteínas NuclearesRESUMO
Neuronal hyperactivity induced by ß-amyloid (Aß) is an early pathological feature in Alzheimer's disease (AD) and contributes to cognitive decline in AD progression. However, the underlying mechanisms are still unclear. Here, we revealed that Aß increased the expression level of synaptic adhesion molecule protocadherin-γC5 (Pcdh-γC5) in a Ca2+-dependent manner, associated with aberrant elevation of synapses in both Aß-treated neurons in vitro and the cortex of APP/PS1 mice in vivo. By using Pcdhgc5 gene knockout mice, we demonstrated the critical function of Pcdh-γC5 in regulating neuronal synapse formation, synaptic transmission, and cognition. To further investigate the role of Pcdh-γC5 in AD pathogenesis, the aberrantly enhanced expression of Pcdh-γC5 in the brain of APP/PS1 mice was knocked down by shRNA. Downregulation of Pcdh-γC5 efficiently rescued neuronal hyperactivity and impaired cognition in APP/PS1 mice. Our findings revealed the pathophysiological role of Pcdh-γC5 in mediating Aß-induced neuronal hyperactivity and cognitive deficits in AD and identified a novel mechanism underlying AD pathogenesis.
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Doença de Alzheimer , Peptídeos beta-Amiloides , Caderinas , Camundongos Knockout , Neurônios , Animais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Caderinas/metabolismo , Caderinas/genética , Camundongos , Neurônios/metabolismo , Camundongos Transgênicos , Sinapses/metabolismo , Sinapses/patologia , Proteínas Relacionadas a Caderinas , Camundongos Endogâmicos C57BL , Masculino , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/genética , Células Cultivadas , Transtornos Cognitivos/metabolismoRESUMO
Background Comparative performance between artificial intelligence (AI) and breast US for women with dense breasts undergoing screening mammography remains unclear. Purpose To compare the performance of mammography alone, mammography with AI, and mammography plus supplemental US for screening women with dense breasts, and to investigate the characteristics of the detected cancers. Materials and Methods A retrospective database search identified consecutive asymptomatic women (≥40 years of age) with dense breasts who underwent mammography plus supplemental whole-breast handheld US from January 2017 to December 2018 at a primary health care center. Sequential reading for mammography alone and mammography with the aid of an AI system was conducted by five breast radiologists, and their recall decisions were recorded. Results of the combined mammography and US examinations were collected from the database. A dedicated breast radiologist reviewed marks for mammography alone or with AI to confirm lesion identification. The reference standard was histologic examination and 1-year follow-up data. The cancer detection rate (CDR) per 1000 screening examinations, sensitivity, specificity, and abnormal interpretation rate (AIR) of mammography alone, mammography with AI, and mammography plus US were compared. Results Among 5707 asymptomatic women (mean age, 52.4 years ± 7.9 [SD]), 33 (0.6%) had cancer (median lesion size, 0.7 cm). Mammography with AI had a higher specificity (95.3% [95% CI: 94.7, 95.8], P = .003) and lower AIR (5.0% [95% CI: 4.5, 5.6], P = .004) than mammography alone (94.3% [95% CI: 93.6, 94.8] and 6.0% [95% CI: 5.4, 6.7], respectively). Mammography plus US had a higher CDR (5.6 vs 3.5 per 1000 examinations, P = .002) and sensitivity (97.0% vs 60.6%, P = .002) but lower specificity (77.6% vs 95.3%, P < .001) and higher AIR (22.9% vs 5.0%, P < .001) than mammography with AI. Supplemental US alone helped detect 12 cancers, mostly stage 0 and I (92%, 11 of 12). Conclusion Although AI improved the specificity of mammography interpretation, mammography plus supplemental US helped detect more node-negative early breast cancers that were undetected using mammography with AI. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Whitman and Destounis in this issue.
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Inteligência Artificial , Densidade da Mama , Neoplasias da Mama , Detecção Precoce de Câncer , Mamografia , Ultrassonografia Mamária , Humanos , Feminino , Mamografia/métodos , Neoplasias da Mama/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Ultrassonografia Mamária/métodos , Detecção Precoce de Câncer/métodos , Adulto , Sensibilidade e Especificidade , Mama/diagnóstico por imagem , IdosoRESUMO
BACKGROUND: The cancer experienced in adolescent and young adult (AYA) could disturb developmental changes and long-term life. The current AYA guidelines and research for survivorship were developed and reported according to the general age range of 15-39 years; however, expected life events vary by diagnosed age. We aimed to examine the social, psychological, and physical well-being of AYA cancer survivors by age at diagnosis using a multinational representative dataset focusing on age at diagnosis. METHODS: We conducted a cross-sectional study using the US and Korean National Health and Nutrition Examination Surveys from 2007 to 2018. Participants diagnosed with any cancer aged 15-39 years and were aged > 18 years at the survey year were defined as AYA cancer survivors. AYA were classified into three groups based on their diagnosed age: adolescent survivors (diagnosed between the ages of 15 and 19, n = 45), young adult survivors (diagnosed between the ages of 20 and 29, n = 238), and late young adult survivors (diagnosed between the ages of 30 and 39, n = 539). We also selected an age-, sex-, race-, and survey year-matched general population with 1:5 ratio among participants without cancer (N = 4110). RESULTS: The average age of the survey was 29.1, 43.7, and 48.7 years for AYA survivors diagnosed during adolescence, young adulthood, and late young adulthood, respectively. Adolescent survivors had more non-couple marital status (adjusted odds ratio (aOR), 1.34; 95% CI, 1.10-1.64) and unemployed (aOR, 1.30; 95% CI, 1.05-1.61) compared to late young adult survivors. Comparing with the matched general, adolescent survivors were more in poor general health (aOR, 4.65; 95% CI, 2.09-10.38) and unemployed (aOR, 2.17; 95% CI, 1.12-4.24) and late young adult survivors were more non-couple (aOR, 1.40; 95% CI, 1.05-1.86). CONCLUSION: This study provides evidence for future studies on long-term health, which may vary according to age at the time of diagnosis among AYA with cancer.
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Sobreviventes de Câncer , Neoplasias , Humanos , Adolescente , Adulto Jovem , Masculino , Feminino , Estudos Transversais , Neoplasias/epidemiologia , Neoplasias/diagnóstico , Adulto , Sobreviventes de Câncer/estatística & dados numéricos , Fatores Etários , Estados Unidos/epidemiologia , Bases de Dados Factuais , República da Coreia/epidemiologia , Inquéritos NutricionaisRESUMO
Organic-inorganic hybrid perovskites have attracted significant attention for optoelectronic applications due to their efficient photoconversion properties. However, grain boundaries and irregular crystal orientations in polycrystalline films remain issues. This study presents a method for producing crystalline-orientation-controlled perovskite single-crystal films using retarded solvent evaporation. It is shown that single-crystal films, grown via inverse temperature crystallization within a confined space, exhibit enhanced optoelectronic property. Using interfacial polymer layer, this method produces high-quality perovskite single-crystalline films with varying crystal orientations. Density functional theory calculations confirm favorable adsorption energies for (110) surfaces with methylammonium iodide and PbI2 terminations on poly(3-hexylthiophene), and stronger adsorption for (224) surfaces with I and methylammonium terminations on polystyrene, influenced by repulsive forces between the thiophene group and the perovskite surface. The correlation between charge transport characteristics and perovskite single-crystalline properties highlights potential advancements in perovskite optoelectronics, improving device performance and reliability.
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Lead halide perovskite solar cells have been emerging as very promising candidates for applications in indoor photovoltaics. To maximize their indoor performance, it is of critical importance to suppress intrinsic defects of the perovskite active layer. Herein, a facile solvent-engineering strategy is developed for effective suppression of both surface and bulk defects in lead halide perovskite indoor solar cells, leading to a high efficiency of 35.99% under the indoor illumination of 1000 lux Cool-white light-emitting diodes. Replacing dimethylformamide (DMF) with N-methyl-2-pyrrolidone (NMP) in the perovskite precursor solvent significantly passivates the intrinsic defects within the thus-prepared perovskite films, prolongs the charge carrier lifetimes and reduces non-radiative charge recombination of the devices. Compared to the DMF, the much higher interaction energy between NMP and formamidinium iodide/lead halide contributes to the markedly improved quality of the perovskite thin films with reduced interfacial halide deficiency and non-radiative charge recombination, which in turn enhances the device performance. This work paves the way for developing efficient indoor perovskite solar cells for the increasing demand for power supplies of Internet-of-Things devices.
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Due to the ultrahigh theoretical specific capacity (3860â mAh g-1) and low redox potential (-3.04â V vs. standard hydrogen electrode), Lithium (Li) metal anode (LMA) received increasing attentions. However, notorious dendrite and volume expansion during the cycling process seriously hinder the development of high energy density Li metal batteries. Constructing three-dimensional (3D) current collectors for Li can fundamentally solve the intrinsic drawback of hostless for Li. Therefore, this review systematically introduces the design and synthesis engineering and the current development status of different 3D collectors in recent years (the current collectors are divided into two major parts: metal-based current collectors and carbon-based current collectors). In the end, some perspectives of the future promotion for LMA application are also presented.
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BACKGROUND: Comorbid depression substantially affects the management of glycemia and diabetes-related complications among patients with type 2 diabetes mellitus. In this study, we sought to determine the association between weight change over 4 years and depression risk among patients with type 2 diabetes mellitus. METHODS: This population-based retrospective cohort study from the National Health Insurance Services of Korea included 1 111 345 patients with type 2 diabetes who were divided into groups according to body weight change over 4 years. Body weight changes were compared with the preceding 4-year period (2005-2008). Depression was defined according to the International Classification of Diseases 10th revision code for depression (F32 and F33) on one or more inpatient or outpatient claims. RESULTS: During a median follow-up of 7.4 years, 244 081 cases of depression were identified. We observed a U-shaped association between body weight change and depression risk with a higher risk among both groups of weight loss (hazard ratio (HR) 1.17, 95% CI 1.15-1.19 for ⩾ -10%; HR 1.07, 95% CI 1.06-1.08 for -10 to -5%) and weight gain (HR 1.06, 95% CI 1.04-1.08 for ⩾10%; HR 1.02, 95% CI 1.01-1.04 for 5-10%) compared with the stable weight group (-5 to 5%). CONCLUSIONS: A U-shaped association between body weight change and depression risk was observed in this large nationwide cohort study. Our study suggests that patients with type 2 diabetes and weight change, either gain or loss, could be considered a high-risk group for depression.
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BACKGROUND: Accurate determination of human epidermal growth factor receptor 2 (HER2) is important for choosing optimal HER2 targeting treatment strategies. HER2-low is currently considered HER2-negative, but patients may be eligible to receive new anti-HER2 drug conjugates. PURPOSE: To use breast MRI BI-RADS features for classifying three HER2 levels, first to distinguish HER2-zero from HER2-low/positive (Task-1), and then to distinguish HER2-low from HER2-positive (Task-2). STUDY TYPE: Retrospective. POPULATION: 621 invasive ductal cancer, 245 HER2-zero, 191 HER2-low, and 185 HER2-positive. For Task-1, 488 cases for training and 133 for testing. For Task-2, 294 cases for training and 82 for testing. FIELD STRENGTH/SEQUENCE: 3.0 T; 3D T1-weighted DCE, short time inversion recovery T2, and single-shot EPI DWI. ASSESSMENT: Pathological information and BI-RADS features were compared. Random Forest was used to select MRI features, and then four machine learning (ML) algorithms: decision tree (DT), support vector machine (SVM), k-nearest neighbors (k-NN), and artificial neural nets (ANN), were applied to build models. STATISTICAL TESTS: Chi-square test, one-way analysis of variance, and Kruskal-Wallis test were performed. The P values <0.05 were considered statistically significant. For ML models, the generated probability was used to construct the ROC curves. RESULTS: Peritumoral edema, the presence of multiple lesions and non-mass enhancement (NME) showed significant differences. For distinguishing HER2-zero from non-zero (low + positive), multiple lesions, edema, margin, and tumor size were selected, and the k-NN model achieved the highest AUC of 0.86 in the training set and 0.79 in the testing set. For differentiating HER2-low from HER2-positive, multiple lesions, edema, and margin were selected, and the DT model achieved the highest AUC of 0.79 in the training set and 0.69 in the testing set. DATA CONCLUSION: BI-RADS features read by radiologists from preoperative MRI can be analyzed using more sophisticated feature selection and ML algorithms to build models for the classification of HER2 status and identify HER2-low. TECHNICAL EFFICACY: Stage 2.
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BACKGROUND: Cancer-associated fibroblasts (CAFs) are key components of the tumor microenvironment (TME) that play an important role in cancer progression. Although the mechanism by which CAFs promote tumorigenesis has been well investigated, the underlying mechanism of CAFs activation by neighboring cancer cells remains elusive. In this study, we aim to investigate the signaling pathways involved in CAFs activation by gastric cancer cells (GC) and to provide insights into the therapeutic targeting of CAFs for overcoming GC. METHODS: Alteration of receptor tyrosine kinase (RTK) activity in CAFs was analyzed using phospho-RTK array. The expression of CAFs effector genes was determined by RT-qPCR or ELISA. The migration and invasion of GC cells co-cultured with CAFs were examined by transwell migration/invasion assay. RESULTS: We found that conditioned media (CM) from GC cells could activate multiple receptor tyrosine kinase signaling pathways, including ERK, AKT, and STAT3. Phospho-RTK array analysis showed that CM from GC cells activated PDGFR tyrosine phosphorylation, but only AKT activation was PDGFR-dependent. Furthermore, we found that connective tissue growth factor (CTGF), a member of the CCN family, was the most pronouncedly induced CAFs effector gene by GC cells. Knockdown of CTGF impaired the ability of CAFs to promote GC cell migration and invasion. Although the PDGFR-AKT pathway was pronouncedly activated in CAFs stimulated by GC cells, its pharmacological inhibition affected neither CTGF induction nor CAFs-induced GC cell migration. Unexpectedly, the knockdown of SRC and SRC-family kinase inhibitors, dasatinib and saracatinib, significantly impaired CTGF induction in activated CAFs and the migration of GC cells co-cultured with CAFs. SRC inhibitors restored the reduced expression of epithelial markers, E-cadherin and Zonula Occludens-1 (ZO-1), in GC cells co-cultured with CAFs, as well as CAFs-induced aggregate formation in a 3D tumor spheroid model. CONCLUSIONS: This study provides a characterization of the signaling pathways and effector genes involved in CAFs activation, and strategies that could effectively inhibit it in the context of GC. Video Abstract.
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Fibroblastos Associados a Câncer , Fator de Crescimento do Tecido Conjuntivo , Neoplasias Gástricas , Humanos , Fibroblastos Associados a Câncer/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fibroblastos/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Neoplasias Gástricas/metabolismo , Microambiente TumoralRESUMO
Transfer RNA-derived small RNAs (tsRNAs) are a class of small non-coding RNA (sncRNA) molecules derived from tRNA, including tRNA derived fragments (tRFs) and tRNA halfs (tiRNAs). tsRNAs can affect cell functions by participating in gene expression regulation, translation regulation, intercellular signal transduction, and immune response. They have been shown to play an important role in various human diseases, including cardiovascular diseases (CVDs). Targeted regulation of tsRNAs expression can affect the progression of CVDs. The tsRNAs induced by pathological conditions can be detected when released into the extracellular, giving them enormous potential as disease biomarkers. Here, we review the biogenesis, degradation process and related functional mechanisms of tsRNAs, and discuss the research progress and application prospects of tsRNAs in different CVDs, to provide a new perspective on the treatment of CVDs.
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Doenças Cardiovasculares , Pequeno RNA não Traduzido , RNA de Transferência , Humanos , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/terapia , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Animais , RNA de Transferência/genética , RNA de Transferência/metabolismo , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/uso terapêutico , Pequeno RNA não Traduzido/metabolismoRESUMO
Infant-type hemispheric glioma (IHG) is a rare pediatric brain tumor with variable response to chemotherapy and radiotherapy. Molecular insights into IHG can be useful in identifying potentially active targeted therapy. A male fetus was found to have congenital hydrocephalus at the gestational age of 37 weeks. Fetal MRI showed a 2.6 × 2.0-cm tumor located at the frontal horn of the left lateral ventricle, involving the left basal nuclei and thalamus. Tumor biopsy at the age of 2 days revealed an IHG consisting of spindle tumor cells with strong expression of GFAP and ALK. Targeted RNA sequencing detected a novel fusion gene of SOX5::ALK. After initial chemotherapy with cyclophosphamide, carboplatin, and etoposide for 2 cycles, the tumor size progressed markedly and the patient underwent a subtotal resection of brain tumor followed by treatment with lorlatinib, an ALK tyrosine kinase inhibitor with central nervous system (CNS) activity. After 3 months of treatment, reduction of tumor size was observed. After 14 months of treatment, partial response was achieved, and the infant had normal growth and development. In conclusion, we identified a case of congenital IHG with a novel SOX5::ALK fusion that had progressed after chemotherapy and showed partial response and clinical benefit after treatment with the CNS-active ALK inhibitor lorlatinib.