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1.
EMBO J ; 43(12): 2424-2452, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38714893

RESUMO

The 16-subunit Constitutive Centromere-associated Network (CCAN)-based inner kinetochore is well-known for connecting centromeric chromatin to the spindle-binding outer kinetochore. Here, we report a non-canonical role for the inner kinetochore in directly regulating sister-chromatid cohesion at centromeres. We provide biochemical, X-ray crystal structure, and intracellular ectopic localization evidence that the inner kinetochore directly binds cohesin, a ring-shaped multi-subunit complex that holds sister chromatids together from S-phase until anaphase onset. This interaction is mediated by binding of the 5-subunit CENP-OPQUR sub-complex of CCAN to the Scc1-SA2 sub-complex of cohesin. Mutation in the CENP-U subunit of the CENP-OPQUR complex that abolishes its binding to the composite interface between Scc1 and SA2 weakens centromeric cohesion, leading to premature separation of sister chromatids during delayed metaphase. We further show that CENP-U competes with the cohesin release factor Wapl for binding the interface of Scc1-SA2, and that the cohesion-protecting role for CENP-U can be bypassed by depleting Wapl. Taken together, this study reveals an inner kinetochore-bound pool of cohesin, which strengthens centromeric sister-chromatid cohesion to resist metaphase spindle pulling forces.


Assuntos
Proteínas de Ciclo Celular , Centrômero , Cromátides , Proteínas Cromossômicas não Histona , Cinetocoros , Cinetocoros/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas Cromossômicas não Histona/genética , Humanos , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Cromátides/metabolismo , Cromátides/genética , Centrômero/metabolismo , Coesinas , Células HeLa , Ligação Proteica , Cristalografia por Raios X
2.
Proc Natl Acad Sci U S A ; 121(29): e2323040121, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38985761

RESUMO

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.


Assuntos
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 , Mutação
3.
Brain ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963812

RESUMO

The medial prefrontal cortex (mPFC) has been implicated in the pathophysiology of social impairments including social fear. However, the precise subcortical partners that mediate mPFC dysfunction on social fear behaviour have not been identified. Employing a social fear conditioning paradigm, we induced robust social fear in mice and found that the lateral habenula (LHb) neurons and LHb-projecting mPFC neurons are synchronously activated during social fear expression. Moreover, optogenetic inhibition of the mPFC-LHb projection significantly reduced social fear responses. Importantly, consistent with animal studies, we observed an elevated prefrontal-habenular functional connectivity in subclinical individuals with higher social anxiety characterized by heightened social fear. These results unravel a crucial role of the prefrontal-habenular circuitry in social fear regulation and suggest that this pathway could serve as a potential target for the treatment of social fear symptom often observed in many psychiatric disorders.

4.
J Biol Chem ; 299(12): 105395, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37890777

RESUMO

Sterile 20-like kinases Mst1 and Mst2 (Mst1/2) and large tumor suppressor 1/2 are core kinases to mediate Hippo signaling in maintaining tissue homeostasis. We have previously demonstrated that Smad ubiquitin (Ub) regulatory factor 1 (Smurf1), a HECT-type E3 ligase, ubiquitinates and in turn destabilizes large tumor suppressor 1/2 to induce the transcriptional output of Hippo signaling. Here, we unexpectedly find that Smurf1 interacts with and polyubiquitinates Mst1/2 by virtue of K27- and K29-linked Ub chains, resulting in the proteasomal degradation of Mst1/2 and attenuation of their tumor-suppressor functions. Among the potential Ub acceptor sites on Mst1/2, K285/K282 are conserved and essential for Smurf1-induced polyubiquitination and degradation of Mst1/2 as well as transcriptional output of Hippo signaling. As a result, K285R/K282R mutation of Mst1/2 not only negates the transcriptional output of Hippo signaling but enhances the tumor-suppressor functions of Mst1/2. Together, we demonstrate that Smurf1-mediated polyubiquitination on K285/K282 of Mst1/2 destabilizes Mst1/2 to attenuate their tumor-suppressor functions. Thus, the present study identifies Smurf1-mediated ubiquitination of Mst1/2 as a hitherto uncharacterized mechanism fine-tuning the Hippo signaling pathway and may provide additional targets for therapeutic intervention of diseases associated with this important pathway.


Assuntos
Genes Supressores de Tumor , Ubiquitina-Proteína Ligases , Via de Sinalização Hippo , Ligases/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Humanos , Animais , Camundongos
5.
Opt Express ; 32(2): 1686-1700, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297715

RESUMO

The decoherence-free subspace (DFS) serves as a protective shield against certain types of environmental noise, allowing the system to remain coherent for extended periods of time. In this paper, we propose two protocols, i.e., one converts two-logic-qubit Knill-Laflamme-Milburn (KLM) state to two-logic-qubit Bell states, and the other converts three-logic-qubit KLM state to three-logic-qubit Greenberger-Horne-Zeilinger states, through cavity-assisted interaction in DFS. Especially, our innovative protocols achieve their objectives in a heralded way, thus enhancing experimental accessibility. Moreover, single photon detectors are incorporated into the setup, which can predict potential failures and ensure seamless interaction between the nitrogen-vacancy center and photons. Rigorous analyses and evaluations of two schemes demonstrate their abilities to achieve near-unit fidelities in principle and exceptional efficiencies. Further, our protocols offer progressive solutions to the challenges posed by decoherence, providing a pathway towards practical quantum technologies.

6.
Environ Sci Technol ; 58(23): 9945-9953, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38806168

RESUMO

Background: understanding the effects of coexposure to compound extreme events, such as air pollution and extreme heat, is important for reducing current and future health burdens. This study investigated the independent and synergistic effects of exposure to air pollution from vegetation fires and extreme heat on all-cause mortality in Upper Northern Thailand. Methods: we used a time-stratified case-crossover study design with a conditional quasi-Poisson model to examine the association between mortality and coexposure to air pollution due to vegetation fire events (fire-PM2.5) and extreme heat. Extreme heat days were defined using the 90th and 99th percentile thresholds for daily maximum temperature. Results: we observed a significant positive excess risk of mortality due to independent exposure to fire-PM2.5 and extreme heat, but not an interactive effect. All-cause mortality risk increased by 0.9% (95% confidence interval (CI): 0.1, 1.8) for each 10 µg/m3 increase in fire-PM2.5 on the same day and by 12.8% (95% CI: 10.5, 15.1) on extreme heat days (90th percentile) relative to nonextreme heat days. Conclusion: this study showed that exposure to PM2.5 from vegetation fires and extreme heat independently increased all-cause mortality risk in UNT. However, there was no evidence of a synergistic effect of these events.


Assuntos
Poluição do Ar , Incêndios , Tailândia , Humanos , Calor Extremo/efeitos adversos , Poluentes Atmosféricos , Material Particulado
7.
BMC Infect Dis ; 24(1): 45, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38172766

RESUMO

BACKGROUND: This study aimed to assess and compare procalcitonin (PCT) and C-reactive protein (CRP) levels between COVID-19 and non-COVID-19 sepsis patients. Additionally, we evaluated the diagnostic efficiency of PCT and CRP in distinguishing between Gram-positive (GP) and Gram-negative (GN) bacterial infections. Moreover, we explored the associations of PCT with specific pathogens in this context. METHODS: The study included 121 consecutive sepsis patients who underwent blood culture testing during the COVID-19 epidemic. PCT and CRP were measured, and reverse transcriptase-polymerase chain reaction (RT-PCR) was employed for the detection of COVID-19 nucleic acid. The Mann-Whitney U-test was used to compare PCT and CRP between the COVID-19 and non-COVID-19 groups. Receiver operating characteristic (ROC) curves were generated to compare PCT and CRP levels in the GN group versus the GP group for assessing the diagnostic efficiency. The kruskal-Wallis H test was applied to assess the impact of specific pathogen groups on PCT concentrations. RESULTS: A total of 121 sepsis patients were categorized into a COVID-19 group (n = 25) and a non-COVID-19 group (n = 96). No significant differences in age and gender were observed between the COVID-19 and non-COVID-19 groups. The comparison of biomarkers between these groups showed no statistically significant differences. The optimal cut-off values for PCT and CRP in differentiating between GP and GN infections were 1.03 ng/mL and 34.02 mg/L, respectively. The area under the ROC curve was 0.689 (95% confidence interval (CI) 0.591-0.786) for PCT and 0.611 (95% CI 0.505-0.717) for CRP. The diagnostic accuracy was 69.42% for PCT and 58.69% for CRP. The study found a significant difference in PCT levels among specific groups of pathogens (P < 0.001), with the highest levels observed in Escherichia coli infections. The frequency of Staphylococcus spp. positive results was significantly higher (36.0%) in COVID-19 compared to non-COVID-19 sepsis patients (P = 0.047). CONCLUSION: Sepsis patients with COVID-19 revealed a significantly higher culture positivity for staphylococcus spp. than the non-COVID-19 group. Both PCT and CRP showed moderate diagnostic efficiency in differentiating between GP and GN bacterial infections. PCT showed potential utility in identifying E. coli infections compared to other pathogens.


Assuntos
COVID-19 , Infecções por Escherichia coli , Infecções por Bactérias Gram-Negativas , Sepse , Humanos , Proteína C-Reativa/análise , Pró-Calcitonina , Escherichia coli/metabolismo , Calcitonina , Estudos Retrospectivos , COVID-19/diagnóstico , Sepse/microbiologia , Biomarcadores , Curva ROC , Infecções por Bactérias Gram-Negativas/microbiologia , Staphylococcus , Teste para COVID-19
8.
Phys Chem Chem Phys ; 26(25): 17902-17909, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38888148

RESUMO

The momentum distribution of photoelectrons in H2+ molecules subjected to an attosecond pulse is theoretically investigated. To better understand the laser-molecule interaction, we develop an in-line photoelectron holography approach that is analogous to optical holography. This approach is specifically suitable for extracting the amplitude and phase of the forward-scattered electron wave packet in a dissociating molecule with atomic precision. We also extend this approach to imaging the transient scattering cross-section of a molecule dressed by a near infrared laser field. This attosecond photoelectron holography sheds light on structural microscopy of dissociating molecules with high spatial-temporal resolution.

9.
Mol Cell ; 61(4): 520-534, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26853146

RESUMO

Altered energy metabolism is a cancer hallmark as malignant cells tailor their metabolic pathways to meet their energy requirements. Glucose and glutamine are the major nutrients that fuel cellular metabolism, and the pathways utilizing these nutrients are often altered in cancer. Here, we show that the long ncRNA CCAT2, located at the 8q24 amplicon on cancer risk-associated rs6983267 SNP, regulates cancer metabolism in vitro and in vivo in an allele-specific manner by binding the Cleavage Factor I (CFIm) complex with distinct affinities for the two subunits (CFIm25 and CFIm68). The CCAT2 interaction with the CFIm complex fine-tunes the alternative splicing of Glutaminase (GLS) by selecting the poly(A) site in intron 14 of the precursor mRNA. These findings uncover a complex, allele-specific regulatory mechanism of cancer metabolism orchestrated by the two alleles of a long ncRNA.


Assuntos
Glutaminase/genética , Neoplasias/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo , Alelos , Processamento Alternativo , Metabolismo Energético , Células HCT116 , Humanos , Neoplasias/genética , Precursores de RNA/química , Precursores de RNA/metabolismo , RNA Mensageiro/metabolismo
10.
Cell Mol Life Sci ; 80(5): 123, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37071198

RESUMO

Alzheimer's disease (AD), as the most common type of dementia, has two pathological hallmarks, extracellular senile plaques composed of ß-amyloid peptides and intracellular neurofibrillary tangles containing phosphorylated-tau protein. Amyloid precursor protein (APP) and tau each play central roles in AD, although how APP and tau interact and synergize in the disease process is largely unknown. Here, we showed that soluble tau interacts with the N-terminal of APP in vitro in cell-free and cell culture systems, which can be further confirmed in vivo in the brain of 3XTg-AD mouse. In addition, APP is involved in the cellular uptake of tau through endocytosis. APP knockdown or N-terminal APP-specific antagonist 6KApoEp can prevent tau uptake in vitro, resulting in an extracellular tau accumulation in cultured neuronal cells. Interestingly, in APP/PS1 transgenic mouse brain, the overexpression of APP exacerbated tau propagation. Moreover, in the human tau transgenic mouse brain, overexpression of APP promotes tau phosphorylation, which is significantly remediated by 6KapoEp. All these results demonstrate the important role of APP in the tauopathy of AD. Targeting the pathological interaction of N-terminal APP with tau may provide an important therapeutic strategy for AD.


Assuntos
Doença de Alzheimer , Precursor de Proteína beta-Amiloide , Camundongos , Humanos , Animais , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo , Modelos Animais de Doenças , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Camundongos Transgênicos
11.
J Ultrasound Med ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38975721

RESUMO

OBJECTIVES: To establish a reliable ultrasound (US) method of evaluating dynamic extrusion of lateral meniscus in healthy population, and to investigate the pattern of dynamic meniscus extrusion (ME) in lateral meniscus under loading conditions. METHODS: The lateral ME was examined via US method in unloaded, double-leg standing, and single-leg standing positions. Two different US measurement methods were compared to the magnetic resonance imaging (MRI) results to determine the optimal measurement methods. The US results obtained by different researchers were tested for interobserver consistency and the results obtained by the same researcher on two separate days were tested for intraobserver consistency. The patterns of dynamic extrusion were compared between medial and lateral sides. RESULTS: A total of healthy 44 volunteers were included in the study, with 86 knees assessed by US, and 25 knees evaluated by MRI. The US evaluation of dynamic lateral ME demonstrated excellent interobserver and intraobserver reliability. The US measurements using method A were consistent with the MRI results with no significant difference (P = .861, intraclass correlation coefficient [ICC] = 0.868), while method B underestimated the lateral ME compared to MRI (P = .001, ICC = 0.649). Lateral ME decreased slightly from unloaded (1.0 ± 0.8 mm) to single-leg standing position (0.8 ± 0.8 mm), whereas medial ME increased significantly in both double-leg and single-leg standing positions (2.4 ± 0.7 mm, 2.6 ± 0.7 mm). CONCLUSION: A novel US evaluation method of lateral ME was established with reliable and accurate results compared to the MRI. Lateral ME in healthy populations decreased slightly as the loadings increased, which was different from the pattern of dynamic extrusion in medial meniscus.

12.
Proc Natl Acad Sci U S A ; 118(18)2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33926963

RESUMO

Stomata in leaves regulate gas exchange between the plant and its atmosphere. Various environmental stimuli elicit abscisic acid (ABA); ABA leads to phosphoactivation of slow anion channel 1 (SLAC1); SLAC1 activity reduces turgor pressure in aperture-defining guard cells; and stomatal closure ensues. We used electrophysiology for functional characterizations of Arabidopsis thaliana SLAC1 (AtSLAC1) and cryoelectron microscopy (cryo-EM) for structural analysis of Brachypodium distachyon SLAC1 (BdSLAC1), at 2.97-Å resolution. We identified 14 phosphorylation sites in AtSLAC1 and showed nearly 330-fold channel-activity enhancement with 4 to 6 of these phosphorylated. Seven SLAC1-conserved arginines are poised in BdSLAC1 for regulatory interaction with the N-terminal extension. This BdSLAC1 structure has its pores closed, in a basal state, spring loaded by phenylalanyl residues in high-energy conformations. SLAC1 phosphorylation fine-tunes an equilibrium between basal and activated SLAC1 trimers, thereby controlling the degree of stomatal opening.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Proteínas de Membrana/genética , Folhas de Planta/genética , Estômatos de Plantas/genética , Ácido Abscísico/metabolismo , Ânions/metabolismo , Arabidopsis/ultraestrutura , Proteínas de Arabidopsis/ultraestrutura , Brachypodium/genética , Brachypodium/ultraestrutura , Dióxido de Carbono/metabolismo , Microscopia Crioeletrônica , Transporte de Íons/genética , Proteínas de Membrana/ultraestrutura , Fosforilação/genética , Folhas de Planta/ultraestrutura , Estômatos de Plantas/ultraestrutura , Conformação Proteica , Transdução de Sinais/genética
13.
Ecotoxicol Environ Saf ; 279: 116474, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38772144

RESUMO

Rhubarb is widely used in health care, but causing a great amount of rhein-containing herbal residue. Rhein with several toxicities might pollute environment, damage ecology and even hazard human health if left untreated. In this study, the degradation effects of bisulfite- (BS) and peroxymonosulfate- (PMS) based oxidation systems on rhein in rhubarb residue were compared and investigated. The effects of BS and PMS with two valence states of ferric ion (Fe) on the degradation of rhein in rhubarb residue were optimized for the selection of optimal oxidation system. The influences of reaction temperature, reaction time and initial pH on the removal of rhein under the optimal oxidation system were evaluated. The chemical profiles of rhubarb residue with and without oxidation process were compared by UPLC-QTOF-MS/MS, and the degradation effects were investigated by PLS-DA and S plot/OPLS-DA analysis. The results manifested that PMS showed relative higher efficiency than BS on the degradation of rhein. Moreover, Fe(III) promoted the degradation effect of PMS, demonstrated that Fe(III)/PMS is the optimal oxidation system to degrade rhein in rhubarb residue. Further studies indicated that the degradation of rhein by the Fe(III)/PMS oxidation system was accelerated with the prolong of reaction time and the elevation of reaction temperature, and also affected by the initial pH. More importantly, Fe(III)/PMS oxidation system could degrade rhein in rhubarb residue completely under the optimal conditions. In conclusion, Fe(III)/PMS oxidation system is a feasible method to treat rhein in rhubarb residue.


Assuntos
Antraquinonas , Oxirredução , Peróxidos , Rheum , Antraquinonas/química , Rheum/química , Peróxidos/química , Espectrometria de Massas em Tandem , Sulfitos/química , Concentração de Íons de Hidrogênio , Compostos Férricos/química , Temperatura
14.
Int J Mol Sci ; 25(7)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38612440

RESUMO

Salinity is one of the most serious threats to sustainable agriculture. The Salt Overly Sensitive (SOS) signaling pathway plays an important role in salinity tolerance in plants, and the SOS2 gene plays a critical role in this pathway. Mulberry not only has important economic value but also is an important ecological tree species; however, the roles of the SOS2 gene associated with salt stress have not been reported in mulberry. To gain insight into the response of mulberry to salt stress, SOS2 (designated MulSOS2) was cloned from mulberry (Morus atropurpurea Roxb), and sequence analysis of the amino acids of MulSOS2 showed that it shares some conserved domains with its homologs from other plant species. Our data showed that the MulSOS2 gene was expressed at different levels in different tissues of mulberry, and its expression was induced substantially not only by NaCl but also by ABA. In addition, MulSOS2 was exogenously expressed in Arabidopsis, and the results showed that under salt stress, transgenic MulSOS2 plants accumulated more proline and less malondialdehyde than the wild-type plants and exhibited increased tolerance to salt stress. Moreover, the MulSOS2 gene was transiently overexpressed in mulberry leaves and stably overexpressed in the hairy roots, and similar results were obtained for resistance to salt stress in transgenic mulberry plants. Taken together, the results of this study are helpful to further explore the function of the MulSOS2 gene, which provides a valuable gene for the genetic breeding of salt tolerance in mulberry.


Assuntos
Arabidopsis , Morus , Tolerância ao Sal/genética , Morus/genética , Melhoramento Vegetal , Estresse Salino , Agricultura , Plantas Geneticamente Modificadas
15.
Health Care Women Int ; : 1-19, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38289647

RESUMO

In this study, the researchers aimed to understand the life experience of older widowed women living alone. Employing a phenomenological approach, we interviewed 15 older women (age 62 to 95) living alone at homes in two villages in Central Java. Through systematic text condensation procedure, we identified five themes: (1) negative feelings at times, (2) getting used to living alone, (3) needing help to support independent living, (4) coping toward negative feelings, (5) attachment to the original house. We depicted the struggles of older women living alone in their homes. Despite the coping strategies they have developed over time, older women needed help during hard times, especially when getting sick. Families and neighbors were the main resources to maintain their independent living. Improving the home environment to increase suitability for aging residents and providing a support system are the options that best fit the needs and values the older women believed.

16.
Haematologica ; 108(5): 1284-1299, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36005562

RESUMO

A hallmark of mixed lineage leukemia gene-rearranged (MLL-r) acute myeloid leukemia that offers an opportunity for targeted therapy is addiction to protein tyrosine kinase signaling. One such signal is the receptor tyrosine kinase Fms-like receptor tyrosine kinase 3 (FLT3) upregulated by cooperation of the transcription factors homeobox A9 (HOXA9) and Meis homeobox 1 (MEIS1). Signal peptide-CUB-EGF-like repeat-containing protein (SCUBE) family proteins have previously been shown to act as a co-receptor for augmenting signaling activity of a receptor tyrosine kinase (e.g., vascular endothelial growth factor receptor). However, whether SCUBE1 is involved in the pathological activation of FLT3 during MLL-r leukemogenesis remains unknown. Here we first show that SCUBE1 is a direct target of HOXA9/MEIS1 that is highly expressed on the MLL-r cell surface and predicts poor prognosis in de novo acute myeloid leukemia. We further demonstrate, by using a conditional knockout mouse model, that Scube1 is required for both the initiation and maintenance of MLL-AF9-induced leukemogenesis in vivo. Further proteomic, molecular and biochemical analyses revealed that the membrane-tethered SCUBE1 binds to the FLT3 ligand and the extracellular ligand-binding domains of FLT3, thus facilitating activation of the signal axis FLT3-LYN (a non-receptor tyrosine kinase) to initiate leukemic growth and survival signals. Importantly, targeting surface SCUBE1 by an anti-SCUBE1 monomethyl auristatin E antibody-drug conjugate led to significantly decreased cell viability specifically in MLL-r leukemia. Our study indicates a novel function of SCUBE1 in leukemia and unravels the molecular mechanism of SCUBE1 in MLL-r acute myeloid leukemia. Thus, SCUBE1 is a potential therapeutic target for treating leukemia caused by MLL rearrangements.


Assuntos
Fator de Crescimento Epidérmico , Leucemia Mieloide Aguda , Animais , Camundongos , Tirosina Quinase 3 Semelhante a fms , Leucemia Mieloide Aguda/patologia , Camundongos Knockout , Proteína Meis1 , Proteína de Leucina Linfoide-Mieloide/metabolismo , Proteômica , Receptores Proteína Tirosina Quinases , Fator A de Crescimento do Endotélio Vascular
17.
Biogerontology ; 24(4): 581-592, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37052773

RESUMO

There is growing evidence that extracellular vesicles (EVs) play a functional role in tissue repair and anti-aging by transferring the contents of donor cells to recipient cells. We hypothesized that Dauer (C. elegans), known as "ageless" nematodes, can also secrete extracellular vesicles and influence the lifespan of C. elegans. Here, we isolated EVs of dauer larvae (dauer EVs). Dauer EVs were characterized using transmission electron microscopy, nanoparticle tracking analysis (NTA), and Western blot analysis. Wild-type C. elegans were fed in the presence or absence of dauer EVs and tested for a range of phenotypes, including longevity, mobility and reproductive capacity. Results showed that dauer EVs increased the average lifespan of nematodes by 15.74%, improved mobility, slowed age-related pigmentation as well as body length, and reduced the accumulation of reactive oxygen species and lipids, while not impairing nematode reproductive capacity. These findings suggest that dauer EVs can extend the lifespan of C. elegans as well as the healthy lifespan by reducing ROS accumulation, with potential anti-aging capacity.


Assuntos
Proteínas de Caenorhabditis elegans , Vesículas Extracelulares , Animais , Caenorhabditis elegans/genética , Larva , Envelhecimento , Proteínas de Caenorhabditis elegans/genética , Longevidade/genética
18.
Br J Anaesth ; 131(2): 253-265, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37474241

RESUMO

BACKGROUND: Delirium is a common and disturbing postoperative complication that might be ameliorated by propofol-based anaesthesia. We therefore tested the primary hypothesis that there is less delirium after propofol-based than after sevoflurane-based anaesthesia within 7 days of major cancer surgery. METHODS: This multicentre randomised trial was conducted in 14 tertiary care hospitals in China. Patients aged 65-90 yr undergoing major cancer surgery were randomised to either propofol-based anaesthesia or to sevoflurane-based anaesthesia. The primary endpoint was the incidence of delirium within 7 postoperative days. RESULTS: A total of 1228 subjects were enrolled and randomised, with 1195 subjects included in the modified intention-to-treat analysis (mean age 71 yr; 422 [35%] women); one subject died before delirium assessment. Delirium occurred in 8.4% (50/597) of subjects given propofol-based anaesthesia vs 12.4% (74/597) of subjects given sevoflurane-based anaesthesia (relative risk 0.68 [95% confidence interval {CI}: 0.48-0.95]; P=0.023; adjusted relative risk 0.59 [95% CI: 0.39-0.90]; P=0.014). Delirium reduction mainly occurred on the first day after surgery, with a prevalence of 5.4% (32/597) with propofol anaesthesia vs 10.7% (64/597) with sevoflurane anaesthesia (relative risk 0.50 [95% CI: 0.33-0.75]; P=0.001). Secondary endpoints, including ICU admission, postoperative duration of hospitalisation, major complications within 30 days, cognitive function at 30 days and 3 yr, and safety outcomes, did not differ significantly between groups. CONCLUSIONS: Delirium was a third less common after propofol than sevoflurane anaesthesia in older patients having major cancer surgery. Clinicians might therefore reasonably select propofol-based anaesthesia in patients at high risk of postoperative delirium. CLINICAL TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR-IPR-15006209) and ClinicalTrials.gov (NCT02662257).


Assuntos
Anestésicos Inalatórios , Delírio do Despertar , Neoplasias , Propofol , Humanos , Feminino , Idoso , Masculino , Propofol/efeitos adversos , Sevoflurano/efeitos adversos , Anestésicos Inalatórios/efeitos adversos , Seguimentos , Anestesia Geral/efeitos adversos , Delírio do Despertar/induzido quimicamente , Neoplasias/cirurgia
19.
Br J Anaesth ; 131(2): 266-275, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37474242

RESUMO

BACKGROUND: Experimental evidence indicates that i.v. anaesthesia might reduce cancer recurrence compared with volatile anaesthesia, but clinical information is observational only. We therefore tested the primary hypothesis that propofol-based anaesthesia improves survival over 3 or more years after potentially curative major cancer surgery. METHODS: This was a long-term follow-up of a multicentre randomised trial in 14 tertiary hospitals in China. We enrolled 1228 patients aged 65-90 yr who were scheduled for major cancer surgery. They were randomised to either propofol-based i.v. anaesthesia or to sevoflurane-based inhalational anaesthesia. The primary endpoint was overall survival after surgery. Secondary endpoints included recurrence-free and event-free survival. RESULTS: Amongst subjects randomised, 1195 (mean age 72 yr; 773 [65%] male) were included in the modified intention-to-treat analysis. At the end of follow-up (median 43 months), there were 188 deaths amongst 598 patients (31%) assigned to propofol-based anaesthesia compared with 175 deaths amongst 597 patients (29%) assigned to sevoflurane-based anaesthesia; adjusted hazard ratio 1.02; 95% confidence interval (CI): 0.83-1.26; P=0.834. Recurrence-free survival was 223/598 (37%) in patients given propofol anaesthesia vs 206/597 (35%) given sevoflurane anaesthesia; adjusted hazard ratio 1.07; 95% CI: 0.89-1.30; P=0.465. Event-free survival was 294/598 (49%) in patients given propofol anaesthesia vs 274/597 (46%) given sevoflurane anaesthesia; adjusted hazard ratio 1.09; 95% CI 0.93 to 1.29; P=0.298. CONCLUSIONS: Long-term survival after major cancer surgery was similar with i.v. and volatile anaesthesia. Propofol-based iv. anaesthesia should not be used for cancer surgery with the expectation that it will improve overall or cancer-specific survival. CLINICAL TRIAL REGISTRATIONS: ChiCTR-IPR-15006209; NCT02660411.


Assuntos
Neoplasias , Propofol , Sevoflurano , Propofol/efeitos adversos , Sevoflurano/efeitos adversos , Neoplasias/cirurgia , Humanos , Masculino , Feminino , Idoso , Seguimentos , Anestésicos Intravenosos , Anestesia por Inalação , Sobreviventes de Câncer
20.
Support Care Cancer ; 31(4): 246, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37000288

RESUMO

PURPOSE: The early integration of palliative care for terminally ill cancer patients improves quality of life. We have developed a new nurse-led consultation model for use in a palliative care consultation service (PCCS) to initiate early palliative care for cancer patients. METHODS: In this 11-year observational study, data were collected from the Hospice-Palliative Clinical Database (HPCD) of Taichung Veterans General Hospital (TCVGH). Terminally ill cancer patients who had received PCCS during the years 2011 to 2021 were enrolled. Trend analysis was performed in order to evaluate differences in outcomes seen within the categories of either a nurse-led consultation model or ordinary consultation model throughout the study period. Analysis included studying the duration of PCCS and DNR declaration, as well as awareness of disease by both patients and families before and after PCCS. RESULTS: In total, 6923 cancer patients with an average age of 64.1 years received PCCS from 2011 to 2021, with the average duration of PCCS being 11.1 days. Three thousand four hundred twenty-one patients (49.4%) received both a nurse consultation and doctor consultation during PCCS. Being admitted to the Department of Hematology, a longer duration of hospitalization, a DNR declaration after PCCS, and having had a PCCS consultation by a nurse only or both with a nurse and a doctor were significant determinants of a PCCS duration of more than 7 days. CONCLUSION: This 11-year observational study shows that the number of terminal cancer patients receiving a novel nurse-led consultation during PCCS has increased significantly during the past decade, while a nurse-led consultation model during PCCS was effective in improving the duration of PCCS among terminally ill cancer patients.


Assuntos
Neoplasias , Cuidados Paliativos , Humanos , Pessoa de Meia-Idade , Doente Terminal , Taiwan , Papel do Profissional de Enfermagem , Qualidade de Vida , Neoplasias/terapia , Encaminhamento e Consulta
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