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1.
Cell ; 170(4): 800-814.e18, 2017 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-28802047

RESUMO

Improved methods for manipulating and analyzing gene function have provided a better understanding of how genes work during organ development and disease. Inducible functional genetic mosaics can be extraordinarily useful in the study of biological systems; however, this experimental approach is still rarely used in vertebrates. This is mainly due to technical difficulties in the assembly of large DNA constructs carrying multiple genes and regulatory elements and their targeting to the genome. In addition, mosaic phenotypic analysis, unlike classical single gene-function analysis, requires clear labeling and detection of multiple cell clones in the same tissue. Here, we describe several methods for the rapid generation of transgenic or gene-targeted mice and embryonic stem (ES) cell lines containing all the necessary elements for inducible, fluorescent, and functional genetic mosaic (ifgMosaic) analysis. This technology enables the interrogation of multiple and combinatorial gene function with high temporal and cellular resolution.


Assuntos
Marcação de Genes/métodos , Animais , Linhagem Celular , Células-Tronco Embrionárias , Camundongos , Camundongos Transgênicos
2.
Am J Hum Genet ; 111(3): 544-561, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38307027

RESUMO

Cervical cancer is caused by human papillomavirus (HPV) infection, has few approved targeted therapeutics, and is the most common cause of cancer death in low-resource countries. We characterized 19 cervical and four head and neck cancer cell lines using long-read DNA and RNA sequencing and identified the HPV types, HPV integration sites, chromosomal alterations, and cancer driver mutations. Structural variation analysis revealed telomeric deletions associated with DNA inversions resulting from breakage-fusion-bridge (BFB) cycles. BFB is a common mechanism of chromosomal alterations in cancer, and our study applies long-read sequencing to this important chromosomal rearrangement type. Analysis of the inversion sites revealed staggered ends consistent with exonuclease digestion of the DNA after breakage. Some BFB events are complex, involving inter- or intra-chromosomal insertions or rearrangements. None of the BFB breakpoints had telomere sequences added to resolve the dicentric chromosomes, and only one BFB breakpoint showed chromothripsis. Five cell lines have a chromosomal region 11q BFB event, with YAP1-BIRC3-BIRC2 amplification. Indeed, YAP1 amplification is associated with a 10-year-earlier age of diagnosis of cervical cancer and is three times more common in African American women. This suggests that individuals with cervical cancer and YAP1-BIRC3-BIRC2 amplification, especially those of African ancestry, might benefit from targeted therapy. In summary, we uncovered valuable insights into the mechanisms and consequences of BFB cycles in cervical cancer using long-read sequencing.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/genética , Aberrações Cromossômicas , Telômero/genética , DNA
3.
Nature ; 589(7842): 437-441, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33299176

RESUMO

The formation of arteries is thought to occur by the induction of a highly conserved arterial genetic programme in a subset of vessels that will later experience an increase in oxygenated blood flow1,2. The initial steps of arterial specification require both the VEGF and Notch signalling pathways3-5. Here, we combine inducible genetic mosaics and transcriptomics to modulate and define the function of these signalling pathways in cell proliferation, arteriovenous differentiation and mobilization. We show that endothelial cells with high levels of VEGF or Notch signalling are intrinsically biased to mobilize and form arteries; however, they are not genetically pre-determined, and can also form veins. Mechanistically, we found that increased levels of VEGF and Notch signalling in pre-arterial capillaries suppresses MYC-dependent metabolic and cell-cycle activities, and promotes the incorporation of endothelial cells into arteries. Mosaic lineage-tracing studies showed that endothelial cells that lack the Notch-RBPJ transcriptional activator complex rarely form arteries; however, these cells regained the ability to form arteries when the function of MYC was suppressed. Thus, the development of arteries does not require the direct induction of a Notch-dependent arterial differentiation programme, but instead depends on the timely suppression of endothelial cell-cycle progression and metabolism, a process that precedes arterial mobilization and complete differentiation.


Assuntos
Artérias/citologia , Artérias/crescimento & desenvolvimento , Proliferação de Células , Células Endoteliais/citologia , Endotélio Vascular/citologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Diferenciação Celular/genética , Linhagem Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/metabolismo , Masculino , Camundongos , Mosaicismo , Mutação , Fenótipo , Proteínas Proto-Oncogênicas c-myc/deficiência , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Receptores Notch/deficiência , Receptores Notch/genética , Receptores Notch/metabolismo , Transdução de Sinais , Fatores de Tempo , Transcrição Gênica , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Veias/citologia
4.
Am J Hum Genet ; 110(3): 427-441, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36787739

RESUMO

Ewing sarcoma (EwS) is a rare bone and soft tissue malignancy driven by chromosomal translocations encoding chimeric transcription factors, such as EWSR1-FLI1, that bind GGAA motifs forming novel enhancers that alter nearby expression. We propose that germline microsatellite variation at the 6p25.1 EwS susceptibility locus could impact downstream gene expression and EwS biology. We performed targeted long-read sequencing of EwS blood DNA to characterize variation and genomic features important for EWSR1-FLI1 binding. We identified 50 microsatellite alleles at 6p25.1 and observed that EwS-affected individuals had longer alleles (>135 bp) with more GGAA repeats. The 6p25.1 GGAA microsatellite showed chromatin features of an EWSR1-FLI1 enhancer and regulated expression of RREB1, a transcription factor associated with RAS/MAPK signaling. RREB1 knockdown reduced proliferation and clonogenic potential and reduced expression of cell cycle and DNA replication genes. Our integrative analysis at 6p25.1 details increased binding of longer GGAA microsatellite alleles with acquired EWSR-FLI1 to promote Ewing sarcomagenesis by RREB1-mediated proliferation.


Assuntos
Neoplasias Ósseas , Sarcoma de Ewing , Humanos , Alelos , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Proteína Proto-Oncogênica c-fli-1/genética , Proteína Proto-Oncogênica c-fli-1/metabolismo , Proteína EWS de Ligação a RNA/genética , Proteína EWS de Ligação a RNA/metabolismo , Sarcoma de Ewing/genética , Sarcoma de Ewing/metabolismo , Sarcoma de Ewing/patologia
5.
PLoS Biol ; 20(3): e3001578, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35263320

RESUMO

Neurodegenerative disorders refer to a group of diseases commonly associated with abnormal protein accumulation and aggregation in the central nervous system. However, the exact role of protein aggregation in the pathophysiology of these disorders remains unclear. This gap in knowledge is due to the lack of experimental models that allow for the spatiotemporal control of protein aggregation, and the investigation of early dynamic events associated with inclusion formation. Here, we report on the development of a light-inducible protein aggregation (LIPA) system that enables spatiotemporal control of α-synuclein (α-syn) aggregation into insoluble deposits called Lewy bodies (LBs), the pathological hallmark of Parkinson disease (PD) and other proteinopathies. We demonstrate that LIPA-α-syn inclusions mimic key biochemical, biophysical, and ultrastructural features of authentic LBs observed in PD-diseased brains. In vivo, LIPA-α-syn aggregates compromise nigrostriatal transmission, induce neurodegeneration and PD-like motor impairments. Collectively, our findings provide a new tool for the generation, visualization, and dissection of the role of α-syn aggregation in PD.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Análise por Conglomerados , Humanos , Corpos de Lewy/metabolismo , Corpos de Lewy/patologia , Doença de Parkinson/metabolismo , Agregados Proteicos , alfa-Sinucleína/metabolismo
6.
Brain ; 147(2): 427-443, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37671615

RESUMO

Mer tyrosine kinase (MerTK) is a receptor tyrosine kinase that mediates non-inflammatory, homeostatic phagocytosis of diverse types of cellular debris. Highly expressed on the surface of microglial cells, MerTK is of importance in brain development, homeostasis, plasticity and disease. Yet, involvement of this receptor in the clearance of protein aggregates that accumulate with ageing and in neurodegenerative diseases has yet to be defined. The current study explored the function of MerTK in the microglial uptake of alpha-synuclein fibrils which play a causative role in the pathobiology of synucleinopathies. Using human primary and induced pluripotent stem cell-derived microglia, the MerTK-dependence of alpha-synuclein fibril internalization was investigated in vitro. Relevance of this pathway in synucleinopathies was assessed through burden analysis of MERTK variants and analysis of MerTK expression in patient-derived cells and tissues. Pharmacological inhibition of MerTK and siRNA-mediated MERTK knockdown both caused a decreased rate of alpha-synuclein fibril internalization by human microglia. Consistent with the non-inflammatory nature of MerTK-mediated phagocytosis, alpha-synuclein fibril internalization was not observed to induce secretion of pro-inflammatory cytokines such as IL-6 or TNF, and downmodulated IL-1ß secretion from microglia. Burden analysis in two independent patient cohorts revealed a significant association between rare functionally deleterious MERTK variants and Parkinson's disease in one of the cohorts (P = 0.002). Despite a small upregulation in MERTK mRNA expression in nigral microglia from Parkinson's disease/Lewy body dementia patients compared to those from non-neurological control donors in a single-nuclei RNA-sequencing dataset (P = 5.08 × 10-21), no significant upregulation in MerTK protein expression was observed in human cortex and substantia nigra lysates from Lewy body dementia patients compared to controls. Taken together, our findings define a novel role for MerTK in mediating the uptake of alpha-synuclein fibrils by human microglia, with possible involvement in limiting alpha-synuclein spread in synucleinopathies such as Parkinson's disease. Upregulation of this pathway in synucleinopathies could have therapeutic values in enhancing alpha-synuclein fibril clearance in the brain.


Assuntos
Doença por Corpos de Lewy , Doença de Parkinson , Sinucleinopatias , Humanos , alfa-Sinucleína/metabolismo , c-Mer Tirosina Quinase/metabolismo , Doença por Corpos de Lewy/metabolismo , Microglia/metabolismo , Doença de Parkinson/metabolismo , Proteínas Tirosina Quinases , Sinucleinopatias/metabolismo
7.
J Cell Physiol ; 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38946060

RESUMO

Skeletal muscle is crucial for animal movement and posture maintenance, and it serves as a significant source of meat in the livestock and poultry industry. The number of muscle fibers differentiated from myoblast in the embryonic stage is one of the factors determining the content of skeletal muscle. Insulin-like growth factor 2 (IGF2), a well-known growth-promoting hormone, is crucial for embryonic and skeletal muscle growth and development. However, the specific molecular mechanism underlying its impact on chicken embryonic myoblast differentiation remains unclear. To elucidate the molecular mechanism by which IGF2 regulates chicken myoblast differentiation, we manipulated IGF2 expression in chicken embryonic myoblast. The results demonstrated that IGF2 was upregulated during chicken skeletal muscle development and myoblast differentiation. On the one hand, we found that IGF2 promotes mitochondrial biogenesis through the PGC1/NRF1/TFAM pathway, thereby enhancing mitochondrial membrane potential, oxidative phosphorylation, and ATP synthesis during myoblast differentiation. This process is mediated by the PI3K/AKT pathway. On the other hand, IGF2 regulates BNIP3-mediated mitophagy, clearing dysfunctional mitochondria. Collectively, our findings confirmed that IGF2 cooperatively regulates mitochondrial biogenesis and mitophagy to remodel the mitochondrial network and enhance mitochondrial function, ultimately promoting myoblast differentiation.

8.
Neuroimage ; 290: 120580, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38508294

RESUMO

Diagnosis of disorders of consciousness (DOC) remains a formidable challenge. Deep learning methods have been widely applied in general neurological and psychiatry disorders, while limited in DOC domain. Considering the successful use of resting-state functional MRI (rs-fMRI) for evaluating patients with DOC, this study seeks to explore the conjunction of deep learning techniques and rs-fMRI in precisely detecting awareness in DOC. We initiated our research with a benchmark dataset comprising 140 participants, including 76 unresponsive wakefulness syndrome (UWS), 25 minimally conscious state (MCS), and 39 Controls, from three independent sites. We developed a cascade 3D EfficientNet-B3-based deep learning framework tailored for discriminating MCS from UWS patients, referred to as "DeepDOC", and compared its performance against five state-of-the-art machine learning models. We also included an independent dataset consists of 11 DOC patients to test whether our model could identify patients with cognitive motor dissociation (CMD), in which DOC patients were behaviorally diagnosed unconscious but could be detected conscious by brain computer interface (BCI) method. Our results demonstrate that DeepDOC outperforms the five machine learning models, achieving an area under curve (AUC) value of 0.927 and accuracy of 0.861 for distinguishing MCS from UWS patients. More importantly, DeepDOC excels in CMD identification, achieving an AUC of 1 and accuracy of 0.909. Using gradient-weighted class activation mapping algorithm, we found that the posterior cortex, encompassing the visual cortex, posterior middle temporal gyrus, posterior cingulate cortex, precuneus, and cerebellum, as making a more substantial contribution to classification compared to other brain regions. This research offers a convenient and accurate method for detecting covert awareness in patients with MCS and CMD using rs-fMRI data.


Assuntos
Transtornos da Consciência , Aprendizado Profundo , Humanos , Encéfalo/diagnóstico por imagem , Estado Vegetativo Persistente , Inconsciência , Estado de Consciência
9.
Breast Cancer Res Treat ; 205(3): 567-577, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38520597

RESUMO

PURPOSE: Recruit and sequence breast cancer subjects in Guatemalan and US Hispanic populations. Identify optimum strategies to recruit Latin American and Hispanic women into genetic studies of breast cancer. METHODS: We used targeted gene sequencing to identify pathogenic variants in 19 familial breast cancer susceptibility genes in DNA from unselected Hispanic breast cancer cases in the US and Guatemala. Recruitment across the US was achieved through community-based strategies. In addition, we obtained patients receiving cancer treatment at major hospitals in Texas and Guatemala. RESULTS: We recruited 287 Hispanic US women, 38 (13%) from community-based and 249 (87%) from hospital-based strategies. In addition, we ascertained 801 Guatemalan women using hospital-based recruitment. In our experience, a hospital-based approach was more efficient than community-based recruitment. In this study, we sequenced 103 US and 137 Guatemalan women and found 11 and 10 pathogenic variants, respectively. The most frequently mutated genes were BRCA1, BRCA2, CHEK2, and ATM. In addition, an analysis of 287 US Hispanic patients with pathology reports showed a significantly higher percentage of triple-negative disease in patients with pathogenic variants (41% vs. 15%). Finally, an analysis of mammography usage in 801 Guatemalan patients found reduced screening in women with a lower socioeconomic status (p < 0.001). CONCLUSION: Guatemalan and US Hispanic women have rates of hereditary breast cancer pathogenic variants similar to other populations and are more likely to have early age at diagnosis, a family history, and a more aggressive disease. Patient recruitment was higher using hospital-based versus community enrollment. This data supports genetic testing in breast cancer patients to reduce breast cancer mortality in Hispanic women.


Assuntos
Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Hispânico ou Latino , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/etnologia , Neoplasias de Mama Triplo Negativas/epidemiologia , Hispânico ou Latino/genética , Hispânico ou Latino/estatística & dados numéricos , Guatemala/epidemiologia , Pessoa de Meia-Idade , Adulto , Idoso , Estados Unidos/epidemiologia , Seleção de Pacientes
10.
Small ; 20(10): e2305020, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37875658

RESUMO

Clean and sustainable energy conversion and storage through electrochemistry shows great promise as an alternative to traditional fuel or fossil-consumption energy systems. With regards to practical and high-efficient electrochemistry application, the rational design of active sites and the accurate description of mechanism remain a challenge. Toward this end, in this Perspective, a unique on-chip micro/nano device coupling nanofabrication and low-dimensional electrochemical materials is presented, in which material structure analysis, field-effect regulation, in situ monitoring, and simulation modeling are highlighted. The critical mechanisms that influence electrochemical response are discussed, and how on-chip micro/nano device distinguishes itself is emphasized. The key challenges and opportunities of on-chip electrochemical platforms are also provided through the Perspective.

11.
Small ; 20(10): e2305767, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37919097

RESUMO

Low-dimensional materials serving as photocatalysts favor providing abundant unsaturated active sites and shortening the charge transport distance, but the high surface energy readily causes the aggregation that limits their application. Herein, it is demonstrated that 2D covalent organic framework (COF) TpBD nanosheets are effective in the dispersion and stabilization of 0D Ni(OH)2 . The COF precursor TpBD is synthesized from the Schiff base condensation of 1,3,5-triformylphloroglucinol (Tp) and benzidine (BD) and exfoliated into 2D nanosheets named BDNs via ultrasonication. The formation of highly dispersive 0D Ni(OH)2 on BDNs is reached under a mild weak basic condition, enabling robust active sites for CO2 adsorption/activation and rapid interface cascaded electron transport channels for the accumulation of long-lived photo-generated charges. The champion catalyst 30%Ni-BDNs effectively catalyze the CO2 to CO conversion under visible-light irradiation, offering a high CO evolution rate of 158.4 mmol g-1 h-1 and turnover frequency of 51 h-1 . By contrast, the counterpart photocatalyst, the bulk TpBD stabilized Ni(OH)2 , affords a much lower CO evolution rate and selectivity. This work demonstrates a new avenue to simultaneously construct efficient active sites and electron transport channels by coupling 0D metal hydroxides and 2D COF nanosheets for CO2 photoreduction.

12.
Small ; : e2400252, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38461522

RESUMO

Owing to the high economic efficiency and energy density potential, manganese-based layer-structured oxides have attracted great interests as cathode materials for potassium ion batteries. In order to alleviate the continuous phase transition and K+ re-embedding from Jahn-Teller distortion, the [Mn-Co-Mo]O6 octahedra are introduced into P3-K0.45 MnO2 herein to optimize the local electron structure. Based on the experimental and computational results, the octahedral center metal molybdenum in [MoO6 ] octahedra proposes a smaller ionic radius and higher oxidation state to induce second-order JTE (pseudo-JTE) distortion in the adjacent [MnO6 ] octahedra. This distortion compresses the [MnO6 ] octahedra along the c-axis, leading to an increased interlayer spacing in the K+ layer. Meanwhile, the Mn3+ /Mn4+ is balanced by [CoO6 ] octahedra and the K+ diffusion pathway is optimized as well. The proposed P3-K0.45 Mn0.9 Co0.05 Mo0.05 O2 cathode material shows an enhanced cycling stability and rate performance. It demonstrates a high capacity of 80.2 mAh g-1 at 100 mAh g-1 and 77.3 mAh g-1 at 500 mAh g-1 . Furthermore, it showcases a 2000 cycles stability with a 59.6% capacity retention. This work presents a promising solution to the challenges faced by manganese-based layered oxide cathodes and offers a deep mechanism understanding and improved electrochemical performance.

13.
Small ; : e2310997, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38353064

RESUMO

Sodium-ion batteries (SIBs) are potential candidates for large energy storage usage because of the natural abundance and cheap sodium. Nevertheless, improving the energy density and cycling steadiness of SIB cathodes remains a challenge. In this work, F-doping Na3 Al2/3 V4/3 (PO4 )3 (NAVP) microspheres (Na3 Al2/3 V4/3 (PO4 )2.9 F0.3 (NAVPF)) are synthesized via spray drying and investigated as SIB cathodes. XRD and Rietveld refinement reveal expanded lattice parameters for NAVPF compared to the undoped sample, and the successful cation doping into the Na superionic conductor (NASICON) framework improves Na+ diffusion channels. The NAVPF delivers an ultrahigh capacity of 148 mAh g-1 at 100 mA g-1 with 90.8% retention after 200 cycles, enabled by the activation of V2+ /V5+ multielectron reaction. Notably, NAVPF delivers an ultrahigh rate performance, with a discharge capacity of 83.6 mAh g-1 at 5000 mA g-1 . In situ XRD demonstrates solid-solution reactions occurred during charge-discharge of NAVPF without two-phase reactions, indicating enhanced structural stability after F-doped. The full cell with NAVPF cathode and Na+ preintercalated hard carbon anode shows a large discharge capacity of 100 mAh g-1 at 100 mA g-1 with 80.2% retention after 100 cycles. This anion doping strategy creates a promising SIB cathode candidate for future high-energy-density energy storage applications.

14.
Diabetes Metab Res Rev ; 40(1): e3706, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37545385

RESUMO

OBJECTIVE: To explore the difference in temperature recovery following cold stimulation between participants with and without diabetes mellitus (DM). MATERIALS AND METHODS: The participants without (control group; n = 25) and with (DM group; n = 26) DM were subjected to local cold stimulation (10º C for 90 s). The thermal images of their hands were continuously captured using a thermal camera within 7 min following cold stimulation, and the highest temperature of each fingertip was calculated. According to the temperature values at different timepoints, the temperature recovery curves were drawn, and the baseline temperature (T-base), initial temperature after cooling (T0), temperature decline amplitude (T-range), and area under the temperature recovery curve > T0 (S) were calculated. Finally, symmetry differences between the two groups were analysed. RESULTS: No statistical differences in the T-base, T0, and T-range were observed between the DM and control groups. After drawing the rewarming curve according to the temperature of the fingertips of the patients following cold stimulation, the S in the DM group was significantly lower than that in the control group (p < 0.05). Furthermore, the asymmetry of the base temperature of the hand was observed in the DM group. CONCLUSIONS: Following cold stimulation, the patients with DM exhibited a different rewarming pattern than those without DM. Thus, cold stimulation tests under infrared thermography may contribute to the early screening of diabetic peripheral neuropathy in future.


Assuntos
Diabetes Mellitus , Termografia , Humanos , Temperatura , Termografia/métodos , Temperatura Baixa , Reaquecimento , Temperatura Cutânea
15.
Nitric Oxide ; 142: 47-57, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38049061

RESUMO

BACKGROUND: Endothelial-mesenchymal transition (EndMT) induced by low shear stress plays an important role in the development of atherosclerosis. However, little is known about the correlation between hydrogen sulfide (H2S), a protective gaseous mediator in atherosclerosis and the process of EndMT. METHODS: We constructed a stable low-shear-stress-induced(2 dyn/cm2) EndMT model, acombined with the pretreatment method of hydrogen sulfide slow release agent(GYY4137). The level of MEST was detected in the common carotid artery of ApoE-/- mice with local carotid artery ligation. The effect of MEST on atherosclerosis development in vivo was verified using ApoE-/- mice were given tail-vein injection of endothelial-specific overexpressed and knock-down MEST adeno-associated virus (AAV). RESULTS: These findings confirmed that MEST is up-regulated in low-shear-stress-induced EndMT and atherosclerosis. In vivo experiments showed that MEST gene overexpression significantly promoted EndMT and aggravated the development of atherosclerotic plaques and MEST gene knockdown significantly inhibited EndMT and delayed the process of atherosclerosis. In vitro, H2S inhibits the expression of MEST and EndMT induced by low shear stress and inhibits EndMT induced by MEST overexpression. Knockdown of NFIL3 inhibit the up regulation of MEST and EndMT induced by low shear stress in HUVECs. CHIP-qPCR assay and Luciferase Reporter assay confirmed that NFIL3 binds to MEST DNA, increases its transcription and H2S inhibits the binding of NFIL3 and MEST DNA, weakening NFIL3's transcriptional promotion of MEST. Mechanistically, H2S increased the sulfhydrylation level of NFIL3, an important upstream transcription factors of MEST. In part, transcription factor NFIL3 restrain its binding to MEST DNA by sulfhydration. CONCLUSIONS: H2S negatively regulate the expression of MEST by sulfhydrylation of NFIL3, thereby inhibiting low-shear-stress-induced EndMT and atherosclerosis.


Assuntos
Aterosclerose , Sulfeto de Hidrogênio , Camundongos , Animais , Humanos , Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/metabolismo , Transição Endotélio-Mesênquima , Aterosclerose/genética , Aterosclerose/metabolismo , Endotélio/metabolismo , DNA/metabolismo , Apolipoproteínas E/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Transição Epitelial-Mesenquimal
16.
Am J Hematol ; 99(1): 113-123, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38009642

RESUMO

Burkitt lymphoma (BL) is an aggressive B-cell lymphoma that significantly contributes to childhood cancer burden in sub-Saharan Africa. Plasmodium falciparum, which causes malaria, is geographically associated with BL, but the evidence remains insufficient for causal inference. Inference could be strengthened by demonstrating that mendelian genes known to protect against malaria-such as the sickle cell trait variant, HBB-rs334(T)-also protect against BL. We investigated this hypothesis among 800 BL cases and 3845 controls in four East African countries using genome-scan data to detect polymorphisms in 22 genes known to affect malaria risk. We fit generalized linear mixed models to estimate odds ratios (OR) and 95% confidence intervals (95% CI), controlling for age, sex, country, and ancestry. The ORs of the loci with BL and P. falciparum infection among controls were correlated (Spearman's ρ = 0.37, p = .039). HBB-rs334(T) was associated with lower P. falciparum infection risk among controls (OR = 0.752, 95% CI 0.628-0.9; p = .00189) and BL risk (OR = 0.687, 95% CI 0.533-0.885; p = .0037). ABO-rs8176703(T) was associated with decreased risk of BL (OR = 0.591, 95% CI 0.379-0.992; p = .00271), but not of P. falciparum infection. Our results increase support for the etiological correlation between P. falciparum and BL risk.


Assuntos
Linfoma de Burkitt , Malária Falciparum , Malária , Traço Falciforme , Humanos , África Oriental , Alelos , Linfoma de Burkitt/epidemiologia , Linfoma de Burkitt/genética , Malária Falciparum/epidemiologia , Malária Falciparum/genética , Malária Falciparum/complicações , Traço Falciforme/epidemiologia , Traço Falciforme/genética , Traço Falciforme/complicações , Nectinas/metabolismo
17.
J Org Chem ; 89(13): 9627-9640, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38888955

RESUMO

The use of amide carbonyl groups of substrates as weakly coordinating directing groups has received a significant amount of attention. Recently, difluoromethylene alkynes have been successfully used in fluorination reactions, resulting in the preparation of various fluorine-containing compounds. This work describes a [4+2] annulation method for creating a range of fluorinated quinolino[2,1-b]quinazolinone derivatives. The derivatives are formed through Rh(III)-catalyzed cascade cyclization of 3-phenylquinazolinones and gem-difluoromethylene alkynes.

18.
J Org Chem ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953547

RESUMO

An efficient [3 + 2] cycloaddition reaction between in situ generated nitrile imines from hydrazonoyl halides and vinylsulfonium salts is developed. The nitrile imines are demonstrated to be a new class of reaction partner for vinylsulfonium salts to conduct the [3 + 2] cycloaddition reaction. The process provides a concise and efficient method for the construction of pyrazole derivatives under mild reaction conditions with broad substrate scope, good product yields, and high regioselectivity.

19.
Infection ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652225

RESUMO

PURPOSE: Physicians may administer Nirmatrelvir-ritonavir to patients who have been symptomatic for more than 5 days. There is currently no clear evidence to support this approach. METHODS: A real-world study was conducted to investigate the potential relationship between the administration of Nirmatrelvir-ritonavir and the rates of intubation or in-hospital mortality among COVID-19 patients who experienced symptoms for more than 5 days. The end point was a composite event of intubation or in-hospital mortality. The outcomes between those patients who received Nirmatrelvir-ritonavir and those who did not were compared. RESULTS: A total of 847 patients were included in the analysis. Among them, 312 patients (36.84%) received Nirmatrelvir-ritonavir. Within the entire population, 86 patients (10.15%) experienced intubation or in-hospital mortality. The main analysis indicated that there was a significant association between the application of Nirmatrelvir-ritonavir and intubation or in-hospital mortality, with an odds ratio of 0.50 (95% confidence interval, 0.28 to 0.87; P = 0.0153) using inverse probability of treatment weighting. The finding was consistent with multiple sensitivity analyses. CONCLUSIONS: The application of Nirmatrelvir-ritonavir was associated with a significantly reduced risk of intubation or death in hospitalized COVID-19 patients who experienced symptoms for more than 5 days as compared to those who did not receive the treatment.

20.
Environ Res ; 250: 118518, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38382662

RESUMO

Plant residues are important sources of soil organic carbon in terrestrial ecosystems. The degradation of plant residue by microbes can influence the soil carbon cycle and sequestration. However, little is known about the microbial composition and function, as well as the accumulation of soil organic carbon (SOC) in response to the inputs of different quality plant residues in the desert environment. The present study evaluated the effects of plant residue addition from Pinus sylvestris var. mongolica (Pi), Artemisia desertorum (Ar) and Amorpha fruticosa (Am) on desert soil microbial community composition and function in a field experiment in the Mu Us Desert. The results showed that the addition of the three plant residues with different C/N ratios induced significant variation in soil microbial communities. The Am treatment (low C/N ratio) improved microbial diversity compared with the Ar and Pi treatments (medium and high C/N ratios). The variations in the taxonomic and functional compositions of the dominant phyla Actinobacteria and Proteobacteria were higher than those of the other phyla among the different treatments. Moreover, the network links between Proteobacteria and other phyla and the CAZyme genes abundances from Proteobacteria increased with increasing residue C/N, whereas those decreased for Actinobacteria. The SOC content of the Am, Ar and Pi treatments increased by 45.73%, 66.54% and 107.99%, respectively, as compared to the original soil. The net SOC accumulation was positively correlated with Proteobacteria abundance and negatively correlated with Actinobacteria abundance. These findings showed that changing the initial quality of plant residue from low C/N to high C/N can result in shifts in taxonomic and functional composition from Actinobacteria to Proteobacteria, which favors SOC accumulation. This study elucidates the ecophysiological roles of Actinobacteria and Proteobacteria in the desert carbon cycle, expands our understanding of the potential microbial-mediated mechanisms by which plant residue inputs affect SOC sequestration in desert soils, and provides valuable guidance for species selection in desert vegetation reconstruction.


Assuntos
Clima Desértico , Microbiologia do Solo , Ecossistema , Carbono/análise , Carbono/metabolismo , Solo/química , Sequestro de Carbono , Microbiota , Bactérias/classificação , Bactérias/genética
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