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1.
BMC Pulm Med ; 24(1): 323, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965505

RESUMO

BACKGROUND: In the tumor microenvironment (TME), a bidirectional relationship exists between hypoxia and lactate metabolism, with each component exerting a reciprocal influence on the other, forming an inextricable link. The aim of the present investigation was to develop a prognostic model by amalgamating genes associated with hypoxia and lactate metabolism. This model is intended to serve as a tool for predicting patient outcomes, including survival rates, the status of the immune microenvironment, and responsiveness to therapy in patients with lung adenocarcinoma (LUAD). METHODS: Transcriptomic sequencing data and patient clinical information specific to LUAD were obtained from comprehensive repositories of The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). A compendium of genes implicated in hypoxia and lactate metabolism was assembled from an array of accessible datasets. Univariate and multivariate Cox regression analyses were employed. Additional investigative procedures, including tumor mutational load (TMB), microsatellite instability (MSI), functional enrichment assessments and the ESTIMATE, CIBERSORT, and TIDE algorithms, were used to evaluate drug sensitivity and predict the efficacy of immune-based therapies. RESULTS: A novel prognostic signature comprising five lactate and hypoxia-related genes (LHRGs), PKFP, SLC2A1, BCAN, CDKN3, and ANLN, was established. This model demonstrated that LUAD patients with elevated LHRG-related risk scores exhibited significantly reduced survival rates. Both univariate and multivariate Cox analyses confirmed that the risk score was a robust prognostic indicator of overall survival. Immunophenotyping revealed increased infiltration of memory CD4 + T cells, dendritic cells and NK cells in patients classified within the high-risk category compared to their low-risk counterparts. Higher probability of mutations in lung adenocarcinoma driver genes in high-risk groups, and the MSI was associated with the risk-score. Functional enrichment analyses indicated a predominance of cell cycle-related pathways in the high-risk group, whereas metabolic pathways were more prevalent in the low-risk group. Moreover, drug sensitivity analyses revealed increased sensitivity to a variety of drugs in the high-risk group, especially inhibitors of the PI3K-AKT, EGFR, and ELK pathways. CONCLUSIONS: This prognostic model integrates lactate metabolism and hypoxia parameters, offering predictive insights regarding survival, immune cell infiltration and functionality, as well as therapeutic responsiveness in LUAD patients. This model may facilitate personalized treatment strategies, tailoring interventions to the unique molecular profile of each patient's disease.


Assuntos
Adenocarcinoma de Pulmão , Ácido Láctico , Neoplasias Pulmonares , Microambiente Tumoral , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/mortalidade , Prognóstico , Microambiente Tumoral/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Ácido Láctico/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética , Idoso , Hipóxia/metabolismo
2.
J Cardiothorac Surg ; 19(1): 301, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38812010

RESUMO

BACKGROUND: Quadricuspid aortic valve (QAV) is a rare congenital anomaly characterized by the presence of four cusps instead of the usual three. It is estimated to occur in less than 0.05% of the population, with Type A (four equal-sized leaflets) accounting for roughly 30% of QAV subtypes. Based on limited clinical series, the usual presentation is progressive aortic valve regurgitation (AR) with symptoms occurring in the fourth to sixth decade of life. Severe aortic valve stenosis (AS) and acute AR are very uncommon. CASE PRESENTATION: We describe two cases of Type A QAV in patients who remained asymptomatic until their seventies with very uncommon presentations: one with severe AS and one with acute, severe AR and flail leaflet. In Case A, a 72-year-old patient with history of moderate AS presents to clinic with progressive exertional dyspnea. During work-up for transcatheter vs. surgical replacement pre-operative computed tomography angiogram (CTA) reveals a quadricuspid aortic valve with severe AS, and the patient undergoes surgical aortic valve replacement. Pre-discharge transthoracic echocardiography (TTE) shows good prosthetic valve function with no gradient or regurgitation. In Case B, a 76-year-old patient is intubated upon arrival to the hospital for acute desaturation, found to have wide open AR on catheterization, and transferred for emergent intervention. Intraoperative TEE reveals QAV with flail leaflet and severe AR. Repair is considered but deferred ultimately due to emergent nature. Post-operative TTE demonstrates good prosthetic valve function with no regurgitation and normal biventricular function. CONCLUSIONS: QAV can present as progressive severe AS and acute AR, with symptoms first occurring in the seventh decade of life. The optimal treatment for QAV remains uncertain. Although aortic valve repair or transcatheter option may be feasible in some patients, aortic valve replacement remains a tenable option.


Assuntos
Valva Aórtica , Humanos , Idoso , Valva Aórtica/anormalidades , Valva Aórtica/cirurgia , Valva Aórtica/diagnóstico por imagem , Masculino , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/diagnóstico , Insuficiência da Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/diagnóstico por imagem , Ecocardiografia , Feminino , Implante de Prótese de Valva Cardíaca
3.
Nature ; 629(8014): 1027-1033, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38811710

RESUMO

Image sensors face substantial challenges when dealing with dynamic, diverse and unpredictable scenes in open-world applications. However, the development of image sensors towards high speed, high resolution, large dynamic range and high precision is limited by power and bandwidth. Here we present a complementary sensing paradigm inspired by the human visual system that involves parsing visual information into primitive-based representations and assembling these primitives to form two complementary vision pathways: a cognition-oriented pathway for accurate cognition and an action-oriented pathway for rapid response. To realize this paradigm, a vision chip called Tianmouc is developed, incorporating a hybrid pixel array and a parallel-and-heterogeneous readout architecture. Leveraging the characteristics of the complementary vision pathway, Tianmouc achieves high-speed sensing of up to 10,000 fps, a dynamic range of 130 dB and an advanced figure of merit in terms of spatial resolution, speed and dynamic range. Furthermore, it adaptively reduces bandwidth by 90%. We demonstrate the integration of a Tianmouc chip into an autonomous driving system, showcasing its abilities to enable accurate, fast and robust perception, even in challenging corner cases on open roads. The primitive-based complementary sensing paradigm helps in overcoming fundamental limitations in developing vision systems for diverse open-world applications.

4.
Eur J Med Chem ; 272: 116477, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38733884

RESUMO

The cellular-mesenchymal epithelial transition factor (c-Met) is a receptor tyrosine kinase (RTK) located on the 7q31 locus encoding the Met proto-oncogene and plays a critical role in regulating cell proliferation, metastasis, differentiation, and apoptosis through various signaling pathways. However, its aberrant activation and overexpression have been implicated in many human cancers. Therefore, c-Met is a promising target for cancer treatment. However, the anticancer effect of selective single-targeted drugs is limited due to the complexity of the signaling system and the involvement of different proteins and enzymes. After inhibiting one pathway, signal molecules can be transmitted through other pathways, resulting in poor efficacy of single-targeted drug therapy. Dual inhibitors that simultaneously block c-Met and another factor can significantly improve efficacy and overcome some of the shortcomings of single-target inhibitors, including drug resistance. In this review, We introduced c-Met kinase and the synergism between c-Met and other anti-tumor targets, then dual-target inhibitors based on c-Met for the treatment of cancers were summarized and their design concepts and structure-activity relationships (SARs) were discussed elaborately, providing a valuable insight for the further development of novel c-Met-based dual inhibitors.


Assuntos
Antineoplásicos , Neoplasias , Inibidores de Proteínas Quinases , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-met , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Relação Estrutura-Atividade , Estrutura Molecular , Proliferação de Células/efeitos dos fármacos , Animais
5.
J Clin Invest ; 134(13)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713523

RESUMO

The smoothened (Smo) receptor facilitates hedgehog signaling between kidney fibroblasts and tubules during acute kidney injury (AKI). Tubule-derived hedgehog is protective in AKI, but the role of fibroblast-selective Smo is unclear. Here, we report that Smo-specific ablation in fibroblasts reduced tubular cell apoptosis and inflammation, enhanced perivascular mesenchymal cell activities, and preserved kidney function after AKI. Global proteomics of these kidneys identified extracellular matrix proteins, and nidogen-1 glycoprotein in particular, as key response markers to AKI. Intriguingly, Smo was bound to nidogen-1 in cells, suggesting that loss of Smo could affect nidogen-1 accessibility. Phosphoproteomics revealed that the 'AKI protector' Wnt signaling pathway was activated in these kidneys. Mechanistically, nidogen-1 interacted with integrin ß1 to induce Wnt in tubules to mitigate AKI. Altogether, our results support that fibroblast-selective Smo dictates AKI fate through cell-matrix interactions, including nidogen-1, and offers a robust resource and path to further dissect AKI pathogenesis.


Assuntos
Injúria Renal Aguda , Fibroblastos , Receptor Smoothened , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Injúria Renal Aguda/genética , Animais , Receptor Smoothened/metabolismo , Receptor Smoothened/genética , Camundongos , Fibroblastos/metabolismo , Fibroblastos/patologia , Via de Sinalização Wnt , Humanos , Camundongos Knockout , Microambiente Celular , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Masculino , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética
6.
FASEB J ; 38(7): e23597, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38581235

RESUMO

Sepsis is a life-threatening condition that occurs when the body responds to an infection but subsequently triggers widespread inflammation and impaired blood flow. These pathologic responses can rapidly cause multiple organ dysfunction or failure either one by one or simultaneously. The fundamental common mechanisms involved in sepsis-induced multiple organ dysfunction remain unclear. Here, employing quantitative global and phosphoproteomics, we examine the liver's temporal proteome and phosphoproteome changes after moderate sepsis induced by cecum ligation and puncture. In total, 4593 global proteins and 1186 phosphoproteins according to 3275 phosphosites were identified. To characterize the liver-kidney comorbidity after sepsis, we developed a mathematical model and performed cross-analyses of liver and kidney proteome data obtained from the same set of mice. Beyond immune response, we showed the commonly disturbed pathways and key regulators of the liver-kidney comorbidity are linked to energy metabolism and consumption. Our data provide open resources to understand the communication between the liver and kidney as they work to fight infection and maintain homeostasis.


Assuntos
Proteoma , Sepse , Camundongos , Animais , Insuficiência de Múltiplos Órgãos/complicações , Insuficiência de Múltiplos Órgãos/patologia , Fígado/metabolismo , Rim/metabolismo , Sepse/metabolismo , Modelos Animais de Doenças
7.
Cell Rep ; 43(5): 114144, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38656874

RESUMO

The molecular mechanisms underlying seizure generation remain elusive, yet they are crucial for developing effective treatments for epilepsy. The current study shows that inhibiting c-Abl tyrosine kinase prevents apoptosis, reduces dendritic spine loss, and maintains N-methyl-d-aspartate (NMDA) receptor subunit 2B (NR2B) phosphorylated in in vitro models of excitotoxicity. Pilocarpine-induced status epilepticus (SE) in mice promotes c-Abl phosphorylation, and disrupting c-Abl activity leads to fewer seizures, increases latency toward SE, and improved animal survival. Currently, clinically used c-Abl inhibitors are non-selective and have poor brain penetration. The allosteric c-Abl inhibitor, neurotinib, used here has favorable potency, selectivity, pharmacokinetics, and vastly improved brain penetration. Neurotinib-administered mice have fewer seizures and improved survival following pilocarpine-SE induction. Our findings reveal c-Abl kinase activation as a key factor in ictogenesis and highlight the impact of its inhibition in preventing the insurgence of epileptic-like seizures in rodents and humans.


Assuntos
Pilocarpina , Proteínas Proto-Oncogênicas c-abl , Convulsões , Animais , Masculino , Camundongos , Apoptose/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/patologia , Neurônios/metabolismo , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-abl/metabolismo , Proteínas Proto-Oncogênicas c-abl/antagonistas & inibidores , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Convulsões/patologia , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/patologia
8.
bioRxiv ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38529509

RESUMO

Brain metastasis of HER2+ breast cancer occurs in about 50% of all women with metastatic HER2+ breast cancer and confers poor prognosis for patients. Despite effective HER2-targeted treatments of peripheral HER2+ breast cancer with Trastuzumab +/-HER2 inhibitors, limited brain permeability renders these treatments inefficient for HER2+ breast cancer brain metastasis (BCBM). The scarcity of suitable patient-derived in-vivo models for HER2+ BCBM has compromised the study of molecular mechanisms that promote growth and therapeutic resistance in brain metastasis. We have generated and characterized new HER2+ BCBM cells (BCBM94) isolated from a patient HER2+ brain metastasis. Repeated hematogenic xenografting of BCBM94 consistently generated BCBM in mice. The clinically used receptor tyrosine kinase inhibitor (RTKi) Lapatinib blocked phosphorylation of all ErbB1-4 receptors and induced the intrinsic apoptosis pathway in BCBM94. Neuregulin-1 (NRG1), a ligand for ErbB3 and ErbB4 that is abundantly expressed in the brain, was able to rescue Lapatinib-induced apoptosis and clonogenic ability in BCBM94 and in HER2+ BT474. ErbB3 was essential to mediate the NRG1-induced survival pathway that involved PI3K-AKT signalling and the phosphorylation of BAD at serine 136 to prevent apoptosis. High throughput RTKi screening identified the brain penetrable Poziotinib as highly potent compound to reduce cell viability in HER2+ BCBM in the presence of NRG1. Successful in-vivo ablation of BCBM94- and BT474-derived HER2+ brain tumors was achieved upon two weeks of treatment with Poziotinib. MRI revealed BCBM remission upon poziotinib, but not with Lapatinib treatment. In conclusion, we have established a new patient-derived HER2+ BCBM in-vivo model and identified Poziotinib as highly efficacious RTKi with excellent brain penetrability that abrogated HER2+ BCBM brain tumors in our mouse models.

9.
Cell Res ; 34(4): 295-308, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38326478

RESUMO

Autoreactive B cells are silenced through receptor editing, clonal deletion and anergy induction. Additional autoreactive B cells are ignorant because of physical segregation from their cognate autoantigen. Unexpectedly, we find that follicular B cell-derived autoantigen, including cell surface molecules such as FcγRIIB, is a class of homeostatic autoantigen that can induce spontaneous germinal centers (GCs) and B cell-reactive autoantibodies in non-autoimmune animals with intact T and B cell repertoires. These B cell-reactive B cells form GCs in a manner dependent on spontaneous follicular helper T (TFH) cells, which preferentially recognize B cell-derived autoantigen, and in a manner constrained by spontaneous follicular regulatory T (TFR) cells, which also carry specificities for B cell-derived autoantigen. B cell-reactive GC cells are continuously generated and, following immunization or infection, become intermixed with foreign antigen-induced GCs. Production of plasma cells and antibodies derived from B cell-reactive GC cells are markedly enhanced by viral infection, potentially increasing the chance for autoimmunity. Consequently, immune homeostasis in healthy animals not only involves classical tolerance of silencing and ignoring autoreactive B cells but also entails a reactive equilibrium attained by a spontaneous B cell-reactive triad of B cells, TFH cells and TFR cells.


Assuntos
Linfócitos T Auxiliares-Indutores , Linfócitos T Reguladores , Animais , Linfócitos T Auxiliares-Indutores/metabolismo , Linfócitos B , Centro Germinativo/metabolismo , Autoantígenos/metabolismo
10.
J Colloid Interface Sci ; 663: 132-142, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38394818

RESUMO

SnO2 layer between Li1.5Al0.5Ge1.5(PO4)3 (LAGP) and lithium anode was prepared through simple scratch-coating process to improve interface properties. The physical phase, morphology, and electrochemical properties of Li/SnO2/LAGP structure were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and electrochemical analytical methods. It was found that SnO2 layer effectively improved the interface stability of LAGP and lithium anode. The prepared Li/SnO2/LAGP/SnO2/Li symmetric cell exhibited a large critical current density of 1.8 mA cm-2 and demonstrated excellent cycling characteristics. The polarization voltages of symmetric cell were 0.1 V and 0.8 V after 1000 h of cycling at current densities of 0.04 mA cm-2 and 0.5 mA cm-2, respectively. Li/SnO2@LAGP/LiFePO4 solid-state full cells were also assembled, exhibiting a discharge specific capacity of 150 mAh g-1 after 200 cycles at 0.1C with capacity retention rate of 96 %. The good interface properties of Li/SnO2/LAGP structure are attributed to the transformation of SnO2 layer into a buffer layer containing Li2O, Sn0, and LixSny alloy during cycling process, which effectively inhibits the reduction reaction between LAGP and lithium anode.

11.
Small ; 20(22): e2306536, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38168889

RESUMO

Effective strategies toward building exquisite nanostructures with enhanced structural integrity and improved reaction kinetics will carry forward the practical application of alloy-based materials as anodes in batteries. Herein, a free-standing 3D carbon nanofiber (CNF) skeleton incorporated with heterostructured binary metal selenides (ZnSe/SnSe) nanoboxes is developed for Na-ion storage anodes, which can facilitate Na+ ion migration, improve structure integrity, and enhance the electrochemical reaction kinetics. During the carbonization and selenization process, selenium/nitrogen (Se/N) is co-doped into the 3D CNF skeleton, which can improve the conductivity and wettability of the CNF matrices. More importantly, the ZnSe/SnSe heterostructures and the Se/N co-doping CNFs can have a synergistic interfacial coupling effect and built-in electric field in the heterogeneous interfaces of ZnSe/SnSe hetero-boundaries as well as the interfaces between the CNF matrix and the selenide heterostructures, which can enable fast ion/electron transport and accelerate surface/internal reaction kinetics for Na-ion storage. The ZnSe/SnSe@Se,N-CNFs exhibit superior Na-ion storage performance than the comparative ZnSe/SnSe, ZnSe and SnSe powders, which deliver an excellent rate performance (882.0, 773.6, 695.7, 634.2, and 559.0 mAh g-1 at current rates of 0.1, 0.2, 0.5, 1, and 2 A g-1) and long-life cycling stability of 587.5 mAh g-1 for 3500 cycles at 2 A g-1.

12.
Sci Rep ; 13(1): 17120, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37816794

RESUMO

The effect of wet environments on the dust cake of filter media was studied. The collapse angles of dust particles and the collapse angles between dust particles and filter media increase with increasing dust moisture content, relative humidity, and spray rate. The smallest growth rate of collapse was observed under dust moisture content, while the largest growth rate occurred under the spray rate condition. The collapse angles between dust particles and filter media of coated filter media were smaller compared to those of mechanical filter media under different wet environments. The dust cake drag coefficients of both filter media initially increase and then decrease with an increase in the dust moisture content, decrease with the acceleration of the relative humidity, and show a pattern of first decreasing and then increasing as the spray rate increases. The dust loading capacity of both filter media follows an opposite trend to that of the dust cake drag coefficients.

13.
ACS Appl Mater Interfaces ; 15(38): 45322-45335, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37708083

RESUMO

The hydrophobic modification of poly(vinyl alcohol) (PVA) film as a biodegradable packaging material has received significant attention in recent research. Despite the use of stearic acid (SA) as a coating for the PVA film, a challenge persists due to the poor compatibility between SA and PVA. This study addressed the aforementioned issue by utilizing (3-aminopropyl)trimethoxysilane (APTMS) as a bridging agent to establish a connection between the hydrophilic PVA film and the hydrophobic SA coating through hydrogen bonding and chemical reactions. First, SEM and EDS analyses confirmed the enhanced interfacial compatibility between the SA coating and the PVA film. Subsequently, the results from 1H NMR, FTIR, and XPS experiments presented evidence of hydrogen bonding and chemical reactions among APTMS, SA, and the PVA film. Interestingly, the PVA-APTMS-SA film demonstrated a contact angle of 120.77°, a water absorption of 7.81%, and a water vapor transmission rate of 8.69 g/m2/h. Furthermore, such a composite film displayed exceptional adhesion performance, requiring detachment stresses of 9.86 ± 0.91 and 6.17 ± 0.75 MPa when tested on glass and marble surfaces, respectively. In conclusion, the PVA-APTMS-SA film exhibited significant potential in extending the freshness of fresh-cut apples, making it a promising eco-friendly packaging material for food preservation.

14.
J Org Chem ; 88(20): 14292-14302, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37768859

RESUMO

A series of calix[4]arenes with upper-rim sulfanylpropyl and p-methoxyphenylazo groups (compounds 8-10) were synthesized and found to be effective chromogenic sensors for selectively detecting Hg2+, Hg+, and Ag+ ions among 18 screened metal perchlorates. In comparison to previously reported diallyl- and dithioacetoxypropyl-substituted calix[4]arenes (5, 6, 14, 15, and 16) and the newly synthesized compound 7, the distal (5,17)-disulfanylpropyl-substituted di-p-methoxyphenylazocalix[4]arene 9 demonstrated superior performance with a limit of detection of 0.028 µM for Hg2+ ions in a chloroform/methanol (v/v = 399/1) cosolvent. Job's plot revealed 1:1 binding stoichiometry for all these upper-rim sulfanylpropyl- and p-methoxyphenylazo-substituted calix[4]arenes 8-10 with Hg2+ ions, and Benesi-Hildebrand plots from ultraviolet/visible (UV-vis) titration spectra were used for the determination of their association constants. Our findings indicated that the distal orientation of two p-methoxyphenylazo and two sulfanylpropyl groups in calix[4]arenes 8-10 is more favorable for binding Hg2+ ions than the proximal (5,11-) orientation; moreover, the adjacent sulfanylpropyl groups exhibited superior coordination as ligands compared to the allyl and thioacetoxypropyl groups. Notably, compounds 8-10 displayed a comparable trend in their association with Ag+ ions, albeit with 1 order of magnitude lower binding constants and a distinct binding mode compared to Hg2+ ions. UV-vis spectroscopy, Job's plots, high-resolution mass spectrometry, and 1H nuclear magnetic resonance titration studies are presented and discussed.

15.
Genome Res ; 33(9): 1609-1621, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37580132

RESUMO

Single-cell transcriptome data has been widely used to reconstruct gene regulatory networks (GRNs) controlling critical biological processes such as development and differentiation. Although a growing list of algorithms has been developed to infer GRNs using such data, achieving an inference accuracy consistently higher than random guessing has remained challenging. To address this, it is essential to delineate how the accuracy of regulatory inference is limited. Here, we systematically characterized factors limiting the accuracy of inferred GRNs and demonstrated that using pre-mRNA information can help improve regulatory inference compared to the typically used information (i.e., mature mRNA). Using kinetic modeling and simulated single-cell data sets, we showed that target genes' mature mRNA levels often fail to accurately report upstream regulatory activities because of gene-level and network-level factors, which can be improved by using pre-mRNA levels. We tested this finding on public single-cell RNA-seq data sets using intronic reads as proxies of pre-mRNA levels and can indeed achieve a higher inference accuracy compared to using exonic reads (corresponding to mature mRNAs). Using experimental data sets, we further validated findings from the simulated data sets and identified factors such as transcription factor activity dynamics influencing the accuracy of pre-mRNA-based inference. This work delineates the fundamental limitations of gene regulatory inference and helps improve GRN inference using single-cell RNA-seq data.


Assuntos
Redes Reguladoras de Genes , Transcriptoma , Precursores de RNA , Algoritmos , RNA Mensageiro/genética
16.
Nucleic Acids Res ; 51(17): 9019-9038, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37587722

RESUMO

Cell-to-cell variability within a clonal population, also known as non-genetic heterogeneity, has created significant challenges for intervening with diseases such as cancer. While non-genetic heterogeneity can arise from the variability in the expression of specific genes, it remains largely unclear whether and how clonal cells could be heterogeneous in the expression of the entire transcriptome. Here, we showed that gene transcriptional activity is globally modulated in individual cancer cells, leading to non-genetic heterogeneity in the global transcription rate. Such heterogeneity contributes to cell-to-cell variability in transcriptome size and displays both dynamic and static characteristics, with the global transcription rate temporally modulated in a cell-cycle-coupled manner and the time-averaged rate being distinct between cells and heritable across generations. Additional evidence indicated the role of ATP metabolism in this heterogeneity, and suggested its implication in intrinsic cancer drug tolerance. Collectively, our work shed light on the mode, mechanism, and implication of a global but often hidden source of non-genetic heterogeneity.


Assuntos
Neoplasias , Transcriptoma , Humanos , Antineoplásicos , Células Clonais , Neoplasias/genética , Neoplasias/patologia
17.
J Surg Educ ; 80(9): 1268-1276, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37482530

RESUMO

OBJECTIVE: We report on the development and implementation of a surgical simulation curriculum for undergraduate medical students in rural Rwanda. DESIGN: This is a narrative report on the development of scenario and procedure-based content for a junior surgical clerkship simulation curriculum by an interdisciplinary team of simulation specialists, surgeons, anesthesiologists, medical educators, and medical students. SETTING: University of Global Health Equity, a new medical school located in Butaro, Rwanda. PARTICIPANTS: Participants in this study consist of simulation and surgical educators, surgeons, anesthesiologists, research fellows and University of Global Health Equity medical students enrolled in the junior surgery clerkship. RESULTS: The simulation training schedule was designed to begin with a 17-session simulation-intensive week, followed by 8 sessions spread over the 11-week clerkship. These sessions combined the use of high-fidelity mannequins with improvised, bench-top surgical simulators like the GlobalSurgBox, and low-cost gelatin-based models to effectively replace resource intensive options. CONCLUSIONS: Emphasis on contextualized content generation, low-cost application, and interdisciplinary design of simulation curricula for low-income settings is essential. The impact of this curriculum on students' knowledge and skill acquisition is being assessed in an ongoing fashion as a substrate for iterative improvement.


Assuntos
Estágio Clínico , Educação de Graduação em Medicina , Treinamento por Simulação , Estudantes de Medicina , Cirurgiões , Humanos , Ruanda , Competência Clínica , Currículo
18.
J Cancer Res Clin Oncol ; 149(13): 11295-11308, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37368120

RESUMO

PURPOSE: AFP appears to be negative in about 30% of overall hepatocellular carcinoma (HCC). Our study aimed to develop a nomogram model to diagnose AFP-negative HCC (AFPN-HCC). PATIENTS AND METHODS: The training set included 294 AFPN-HCC patients, 159 healthy objects, 63 patients with chronic hepatitis B(CHB), and 64 patients with liver cirrhosis (LC). And the validation set enrolled 137 healthy controls objects, 47 CHB patients and 45 patients with LC. LASSO, univariate, and multivariable logistic regression analysis were performed to construct the model and then transformed into a visualized nomogram. The receiver operating characteristic (ROC) curves, the calibration curve, decision curve analysis (DCA), and clinical impact curve (CIC) were further used for validation. RESULTS: Four variables including age, PIVKA-II, platelet (PLT) counts, and prothrombin time (PT) were selected to establish the nomogram. The area under the curve (AUC) of the ROC to distinguish AFPN-HCC patients was 0.937(95% CI 0.892-0.938) in training set and 0.942(95% CI 0.921-0.963) in validation set. We also found that the model had high diagnostic value for small-size HCC (tumor size < 5 cm) (AUC = 0.886) and HBV surface antigen-positive AFPN-HCC (AUC = 0.883). CONCLUSIONS: Our model was effective for discrimination of AFPN-HCC from patients with benign liver diseases and healthy controls, and might be helpful for the diagnosis for AFPN-HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , alfa-Fetoproteínas , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Biomarcadores , Cirrose Hepática/diagnóstico , Curva ROC , Biomarcadores Tumorais
19.
Cell Rep ; 42(7): 112663, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37347664

RESUMO

While it has been established that the responses of T cells to antigens are combinatorially regulated by multiple signaling pathways, it remains elusive what mechanisms cells utilize to quantitatively modulate T cell responses during pathway integration. Here, we show that two key pathways in T cell signaling, calcium/nuclear factor of activated T cells (NFAT) and protein kinase C (PKC)/nuclear factor κB (NF-κB), integrate through a dynamic and combinatorial strategy to fine-tune T cell response genes. At the cis-regulatory level, the two pathways integrate through co-binding of NFAT and NF-κB to immune response genes. Pathway integration is further regulated temporally, where T cell receptor (TCR) and chimeric antigen receptor (CAR) activation signals modulate the temporal relationships between the nuclear localization dynamics of NFAT and NF-κB. Such physical and temporal integrations together contribute to distinct modes of expression modulation for genes. Thus, the temporal relationships between regulators can be modulated to affect their co-targets during immune responses, underscoring the importance of dynamic combinatorial regulation in cellular signaling.


Assuntos
NF-kappa B , Receptores de Antígenos Quiméricos , Humanos , NF-kappa B/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Transdução de Sinais , Fatores de Transcrição NFATC/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/metabolismo
20.
J Am Coll Surg ; 237(3): 533-544, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37194947

RESUMO

BACKGROUND: Open and robotic-assisted transthoracic approaches for diaphragm plication are accepted surgical interventions for diaphragm paralysis and eventration. However, long-term patient-reported symptom improvement and quality of life (QOL) remains unclear. STUDY DESIGN: A telephone-based survey was developed focusing on postoperative symptom improvement and QOL. Patients who underwent open or robotic-assisted transthoracic diaphragm plication (2008-2020) across three institutions were invited to participate. Patients who responded and provided consent were surveyed. Likert responses on symptom severity were dichotomized and rates before and after surgery were compared using McNemar's test. RESULTS: Forty-one percent of patients participated (43 of 105 responded, mean age 61.0 years, 67.4% male, 37.2% robotic-assisted surgery), with an average time between surgery and survey of 4.1 ± 3.2 years. Patients reported significant improvement in dyspnea while lying flat (67.4% pre- vs 27.9% postoperative, p < 0.001), dyspnea at rest (55.8% pre- vs 11.6% postoperative, p < 0.001), dyspnea with activity (90.7% pre- vs 55.8% postoperative, p < 0.001), dyspnea while bending over (79.1% pre- vs 34.9% postoperative, p < 0.001), and fatigue (67.4% pre- vs 41.9% postoperative, p = 0.008). There was no statistical improvement in chronic cough. 86% of patients reported improved overall QOL, 79% had increased exercise capacity, and 86% would recommend surgery to a friend with a similar problem. Analysis comparing open and robotic-assisted approaches found no statistically significant differences in symptom improvement or QOL responses between the groups. CONCLUSIONS: Patients report significantly improved dyspneic and fatigue symptoms after transthoracic diaphragm plication, regardless of open or robotic-assisted approach. The majority of patients report improved QOL and exercise capacity.


Assuntos
Diafragma , Procedimentos Cirúrgicos Robóticos , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Diafragma/cirurgia , Qualidade de Vida , Resultado do Tratamento , Dispneia/etiologia , Dispneia/cirurgia , Fadiga , Medidas de Resultados Relatados pelo Paciente
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