Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 484
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
EMBO J ; 43(6): 931-955, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38360997

RESUMO

The Von Hippel-Lindau (VHL) protein, which is frequently mutated in clear-cell renal cell carcinoma (ccRCC), is a master regulator of hypoxia-inducible factor (HIF) that is involved in oxidative stresses. However, whether VHL possesses HIF-independent tumor-suppressing activity remains largely unclear. Here, we demonstrate that VHL suppresses nutrient stress-induced autophagy, and its deficiency in sporadic ccRCC specimens is linked to substantially elevated levels of autophagy and correlates with poorer patient prognosis. Mechanistically, VHL directly binds to the autophagy regulator Beclin1, after its PHD1-mediated hydroxylation on Pro54. This binding inhibits the association of Beclin1-VPS34 complexes with ATG14L, thereby inhibiting autophagy initiation in response to nutrient deficiency. Expression of non-hydroxylatable Beclin1 P54A abrogates VHL-mediated autophagy inhibition and significantly reduces the tumor-suppressing effect of VHL. In addition, Beclin1 P54-OH levels are inversely correlated with autophagy levels in wild-type VHL-expressing human ccRCC specimens, and with poor patient prognosis. Furthermore, combined treatment of VHL-deficient mouse tumors with autophagy inhibitors and HIF2α inhibitors suppresses tumor growth. These findings reveal an unexpected mechanism by which VHL suppresses tumor growth, and suggest a potential treatment for ccRCC through combined inhibition of both autophagy and HIF2α.


Assuntos
Proteína Beclina-1 , Carcinoma de Células Renais , Neoplasias Renais , Proteína Supressora de Tumor Von Hippel-Lindau , Animais , Humanos , Camundongos , Autofagia , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Carcinoma de Células Renais/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Hidroxilação , Neoplasias Renais/metabolismo , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo
2.
Nature ; 581(7807): 204-208, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32405000

RESUMO

It has been speculated that brain activities might directly control adaptive immune responses in lymphoid organs, although there is little evidence for this. Here we show that splenic denervation in mice specifically compromises the formation of plasma cells during a T cell-dependent but not T cell-independent immune response. Splenic nerve activity enhances plasma cell production in a manner that requires B-cell responsiveness to acetylcholine mediated by the α9 nicotinic receptor, and T cells that express choline acetyl transferase1,2 probably act as a relay between the noradrenergic nerve and acetylcholine-responding B cells. We show that neurons in the central nucleus of the amygdala (CeA) and the paraventricular nucleus (PVN) that express corticotropin-releasing hormone (CRH) are connected to the splenic nerve; ablation or pharmacogenetic inhibition of these neurons reduces plasma cell formation, whereas pharmacogenetic activation of these neurons increases plasma cell abundance after immunization. In a newly developed behaviour regimen, mice are made to stand on an elevated platform, leading to activation of CeA and PVN CRH neurons and increased plasma cell formation. In immunized mice, the elevated platform regimen induces an increase in antigen-specific IgG antibodies in a manner that depends on CRH neurons in the CeA and PVN, an intact splenic nerve, and B cell expression of the α9 acetylcholine receptor. By identifying a specific brain-spleen neural connection that autonomically enhances humoral responses and demonstrating immune stimulation by a bodily behaviour, our study reveals brain control of adaptive immunity and suggests the possibility to enhance immunocompetency by behavioural intervention.


Assuntos
Comportamento Animal/fisiologia , Encéfalo/fisiologia , Imunidade Humoral/imunologia , Baço/imunologia , Baço/inervação , Acetilcolina/metabolismo , Acetilcolina/farmacologia , Neurônios Adrenérgicos/metabolismo , Tonsila do Cerebelo/citologia , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/metabolismo , Animais , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Colina O-Acetiltransferase/metabolismo , Hormônio Liberador da Corticotropina/metabolismo , Hemocianinas/imunologia , Imunoglobulina G/imunologia , Ativação Linfocitária , Masculino , Camundongos , Núcleo Hipotalâmico Paraventricular/citologia , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/metabolismo , Plasmócitos/citologia , Plasmócitos/efeitos dos fármacos , Plasmócitos/imunologia , Receptores Nicotínicos/deficiência , Receptores Nicotínicos/metabolismo , Baço/citologia , Baço/efeitos dos fármacos , Estresse Psicológico/imunologia , Estresse Psicológico/metabolismo , Linfócitos T/imunologia
3.
Plant Physiol ; 195(3): 1925-1940, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38427921

RESUMO

Leaf senescence is a vital aspect of plant physiology and stress responses and is induced by endogenous factors and environmental cues. The plant-specific NAC (NAM, ATAF1/2, CUC2) transcription factor family influences growth, development, and stress responses in Arabidopsis (Arabidopsis thaliana) and other species. However, the roles of NACs in tobacco (Nicotiana tabacum) leaf senescence are still unclear. Here, we report that NtNAC56 regulates leaf senescence in tobacco. Transgenic plants overexpressing NtNAC56 (NtNAC56-OE) showed induction of senescence-related genes and exhibited early senescence and lower chlorophyll content compared to wild-type (WT) plants and the Ntnac56-19 mutant. In addition, root development and seed germination were inhibited in the NtNAC56-OE lines. Transmission electron microscopy observations accompanied by physiological and biochemical assays revealed that NtNAC56 overexpression triggers chloroplast degradation and reactive oxygen species accumulation in tobacco leaves. Transcriptome analysis demonstrated that NtNAC56 activates leaf senescence-related genes and jasmonic acid (JA) biosynthesis pathway genes. In addition, the JA content of NtNAC56-OE plants was higher than in WT plants, and JA treatment induced NtNAC56 expression. We performed DNA affinity purification sequencing to identify direct targets of NtNAC56, among which we focused on LIPOXYGENASE 5 (NtLOX5), a key gene in JA biosynthesis. A dual-luciferase reporter assay and a yeast one-hybrid assay confirmed that NtNAC56 directly binds to the TTTCTT motif in the NtLOX5 promoter. Our results reveal a mechanism whereby NtNAC56 regulates JA-induced leaf senescence in tobacco and provide a strategy for genetically manipulating leaf senescence and plant growth.


Assuntos
Ciclopentanos , Regulação da Expressão Gênica de Plantas , Nicotiana , Oxilipinas , Folhas de Planta , Proteínas de Plantas , Senescência Vegetal , Plantas Geneticamente Modificadas , Fatores de Transcrição , Nicotiana/genética , Nicotiana/fisiologia , Nicotiana/efeitos dos fármacos , Nicotiana/crescimento & desenvolvimento , Oxilipinas/metabolismo , Oxilipinas/farmacologia , Ciclopentanos/metabolismo , Ciclopentanos/farmacologia , Folhas de Planta/metabolismo , Folhas de Planta/genética , Folhas de Planta/fisiologia , Senescência Vegetal/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Espécies Reativas de Oxigênio/metabolismo , Clorofila/metabolismo , Cloroplastos/metabolismo , Cloroplastos/ultraestrutura , Regiões Promotoras Genéticas/genética
4.
FASEB J ; 38(5): e23519, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38457249

RESUMO

ARL3 is essential for cilia development, and mutations in ARL3 are closely associated with ciliopathies. In a previous study, we observed distinct phenotypes of retinal dystrophy in patients with heterozygous ARL3T31A and compound heterozygous ARL3T31A/C118F mutations, indicating that different mutation types may exert diverse effects on their functions. Here, we generated transformed immortal fibroblast cells from patients carrying heterozygous ARL3T31A and compound heterozygous ARL3T31A/C118F mutations, and systematically evaluated their cilia morphology and function, which were further validated in ARPE-19 cells. Results showed that both ARL3T31A and ARL3T31A/C118F mutations led to a decrease in cilium formation. The ARL3T31A/C118F mutations caused significantly elongated cilia and impaired retrograde transport, whereas the ARL3T31A mutation did not induce significant changes in fibroblasts. RNA-sequencing results indicated that compared to ARL3T31A , ARL3T31A/C118F fibroblasts exhibited a higher enrichment of biological processes related to neuron projection development, tissue morphogenesis, and extracellular matrix (ECM) organization, with noticeable alterations in pathways such as ECM-receptor interaction, focal adhesion, and TGF-ß signaling. Similar changes were observed in the proteomic results in ARPE-19 cells. Core regulated genes including IQUB, UNC13D, RAB3IP, and GRIP1 were specifically downregulated in the ARL3T31A/C118F group, and expressions of IQUB, NPM2, and SLC38A4 were further validated. Additionally, IQUB showed a rescuing effect on the overlong cilia observed in ARL3T31A/C118F fibroblasts. Our results not only enhance our understanding of ARL3-related diseases but also provide new insights into the analysis of heterozygous and compound heterozygous mutations in genetics.


Assuntos
Cílios , Proteômica , Humanos , Cílios/genética , Cílios/metabolismo , Transporte Proteico , Fatores de Ribosilação do ADP/genética , Fatores de Ribosilação do ADP/metabolismo , Mutação , Fibroblastos/metabolismo , Proteínas de Membrana/metabolismo
5.
Bioessays ; 45(8): e2200242, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37338306

RESUMO

DNA extraction, playing an irreplaceable role in molecular biology as it is an essential step prior to various downstream biological analyses. Thus, the accuracy and reliability of downstream research outcomes depend largely on upstream DNA extraction methodology. However, with the advancement of downstream DNA detection techniques, the development of corresponding DNA extraction methods is lagging behind. The most innovative DNA extraction techniques are silica- or magnetic-based. Recent studies have demonstrated that plant fiber-based adsorbents (PF-BAs) have stronger DNA capturing ability than classic materials. Moreover, magnetic ionic liquid (MIL)-based DNA extraction has gathered attention lately, and extrachromosomal circular DNA (eccDNA), cell-free DNA (cfDNA), and microbial community DNA are current research hotspots. These require specific extraction methods, along with constant improvements in the way they are used. This review discusses the significance as well as the direction of innovation of DNA extraction methods to try to provide valuable references including current status and trends for DNA extraction.


Assuntos
DNA , Líquidos Iônicos , Reprodutibilidade dos Testes
6.
Proc Natl Acad Sci U S A ; 119(15): e2116844119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35377811

RESUMO

In pathological or artificial conditions, memory can be formed as silenced engrams that are unavailable for retrieval by presenting conditioned stimuli but can be artificially switched into the latent state so that natural recall is allowed. However, it remains unclear whether such different states of engrams bear any physiological significance and can be switched through physiological mechanisms. Here, we show that an acute social reward experience switches the silent memory engram into the latent state. Conversely, an acute social stress causes transient forgetting via turning a latent memory engram into a silent state. Such emotion-driven bidirectional switching between latent and silent states of engrams is mediated through regulation of Rac1 activity­dependent reversible forgetting in the hippocampus, as stress-activated Rac1 suppresses retrieval, while reward recovers silenced memory under amnesia by inhibiting Rac1. Thus, data presented reveal hippocampal Rac1 activity as the basis for emotion-mediated switching between latent and silent engrams to achieve emotion-driven behavioral flexibility.


Assuntos
Região CA1 Hipocampal , Rememoração Mental , Comportamento Social , Proteínas rac1 de Ligação ao GTP , Animais , Região CA1 Hipocampal/enzimologia , Sinais (Psicologia) , Rememoração Mental/fisiologia , Camundongos , Neurônios/enzimologia , Recompensa , Proteínas rac1 de Ligação ao GTP/metabolismo
7.
Stroke ; 55(4): 856-865, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38362756

RESUMO

BACKGROUND: The present study aimed to evaluate the efficacy and safety of intravenous tirofiban versus alteplase before endovascular treatment (EVT) in acute ischemic stroke patients with intracranial large vessel occlusion. METHODS: This was a post hoc analysis using data from 2 multicenter, randomized trials: the DEVT trial (Direct Endovascular Treatment for Large Vessel Occlusion Stroke) from May 2018 to May 2020 and the RESCUE BT trial (Intravenous Tirofiban Before Endovascular Thrombectomy for Acute Ischemic Stroke) from October 2018 to October 2021. Patients with acute intracranial large vessel occlusion within 4.5 hours from last known well were dichotomized into 2 groups: tirofiban plus EVT versus alteplase bridging with EVT. The primary outcome was functional independence (modified Rankin Scale score of 0-2) at 90 days. Safety outcomes included symptomatic intracranial hemorrhage and 3-month mortality. Multivariable logistic regression (adjusting for baseline systolic blood pressure, occlusion site, onset-to-puncture time, anesthesia, and first choice of EVT) and propensity score overlap weighting (balance in demographic covariates, stroke characteristics, and initial management between groups) were performed. RESULTS: One-hundred and eighteen alteplase-treated patients in the DEVT trial and 98 tirofiban-treated patients in the RESCUE BT trial were included (median age, 70 years; 115 [53.2%] men). The rate of functional independence was 60.2% in the tirofiban group compared with 46.6% in the alteplase group (adjusted odds ratio, 1.25 [95% CI, 0.60-2.63]). Compared with alteplase, tirofiban was not associated with increased risk of symptomatic intracranial hemorrhage (6.8% versus 9.2%; P=0.51) and mortality (17.8% versus 19.4%; P=0.76). The propensity score overlap weighting analyses showed consistent outcomes. CONCLUSIONS: Among patients with intracranial large vessel occlusion within 4.5 hours of onset, tirofiban plus EVT was comparable to alteplase bridging with EVT regarding the efficacy and safety outcomes. These findings should be interpreted as preliminary and require confirmation in a randomized trial. REGISTRATION: URL: https://www.chictr.org.cn; Unique identifiers: ChiCTR-IOR-17013568 and ChiCTR-INR-17014167.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Humanos , Idoso , Feminino , Ativador de Plasminogênio Tecidual/uso terapêutico , Tirofibana/uso terapêutico , Fibrinolíticos , AVC Isquêmico/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/cirurgia , Terapia Trombolítica/efeitos adversos , Resultado do Tratamento , Procedimentos Endovasculares/efeitos adversos , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos , Hemorragias Intracranianas/etiologia , Hemorragias Intracranianas/induzido quimicamente , Estudos Multicêntricos como Assunto
8.
Br J Haematol ; 204(5): 1780-1789, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38369805

RESUMO

Chimeric antigen receptor T-cell (CAR-T) therapy targeting B-cell maturation antigen (BCMA) has shown profound efficacy and manageable toxicity in patients with relapsed/refractory multiple myeloma (RRMM). However, determining the best course of treatment for post-CAR-T therapy relapse remains a significant challenge. We conducted a retrospective analysis of patients from the phase I LEGEND-2 study (NCT03090659) enrolled at the Xi'an site, analysing the first salvage line of therapy and outcomes in patients with RRMM who progressed after receiving LCAR-B38M CAR-T therapy. Of 45 eligible patients, 34 (76%) had progressive disease (PD). Overall response rate (ORR) to salvage treatment was 50.0%. Median progression-free survival (PFS) after starting salvage treatment was 16.3 months. Median PFS of patients receiving proteasome inhibitor (PI)-based combination therapy was longer (28.2 months) than that of patients receiving a second BCMA CAR-T (including LCAR-B38M; 3.9 months, p = 0.0022) or chemotherapy (1.67 months, p = 0.0001). All patients with extramedullary disease at baseline (n = 11) progressed after CAR-T therapy; ORR to salvage therapy was 25.0% and median PFS was 9.7 months. In conclusion, salvage therapy in patients with PD after receiving LCAR-B38M CAR-T cells produced moderate efficacy, with better outcomes for PI-based salvage regimens.


Assuntos
Antígeno de Maturação de Linfócitos B , Imunoterapia Adotiva , Mieloma Múltiplo , Terapia de Salvação , Humanos , Mieloma Múltiplo/terapia , Mieloma Múltiplo/mortalidade , Terapia de Salvação/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Idoso , Adulto , Resultado do Tratamento
9.
Plant Physiol ; 191(4): 2385-2399, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36617228

RESUMO

Glandular trichomes are universal epidermal structures that produce abundant specialized metabolites. However, knowledge of the initiation of glandular heads in glandular trichomes is limited. Herein, we found an intrinsic link of morphogenesis between glandular trichomes and non-glandular trichomes. Two novel homeodomain leucine zipper II members in tobacco (Nicotiana tabacum), NtHD9 and NtHD12, played important roles in long glandular trichome formation: NtHD9 was responsible for glandular head formation, while NtHD12 simultaneously controlled the formation of stalks and glandular heads. DAP-seq analysis suggested that NtHD9 can bind to the KKGCATTWAWTR motif of the cytochromes P450 94C1 (NtCYP94C1) promoter, which is involved in jasmonoyl-isoleucine oxidation. RNA-seq analysis of non-transformed tobacco and nthd9 plants revealed that NtHD9 modulates the expression of jasmonate (JA) signaling- and six trichome development-related genes. Notably, MeJA treatment restored the morphogenesis of long glandular trichomes in nthd9 and nthd12 plants, and the size of glandular heads increased with increasing MeJA concentration. However, the phenotype of long glandular trichome absence in double mutants of NtHD9 and NtHD12 could not be restored by MeJA. Our data demonstrate that NtHD9 and NtHD12 have distinct major functions yet overlapping roles in long glandular trichome formation via JA signaling.


Assuntos
Fatores de Transcrição , Tricomas , Fatores de Transcrição/metabolismo , Tricomas/genética , Tricomas/metabolismo , Proteínas de Plantas/metabolismo , Ciclopentanos/farmacologia , Ciclopentanos/metabolismo , Nicotiana/genética , Nicotiana/metabolismo
10.
BMC Public Health ; 24(1): 1194, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685020

RESUMO

BACKGROUND: TikTok is emerging as a vital platform for health information dissemination. Despite myopia being a global public health issue, the high-quality myopia information shared by health educators often fails to go viral. It is imperative to analyze the factors influencing video quality and popularity, especially from diverse perspectives of researchers, health educators, and audiences. METHODS: TikTok myopia-related videos were retrieved using TikTok's default comprehensive search (DCS) and most liked search (MLS) strategies. Venn diagrams were employed to illustrate the relationships and commonalities between the two strategies across four sample sizes (top 200, 150, 100, and 50). Video metadata, including details such as creator information, production properties, upload time, video duration, and viewer engagement, were collected. Video quality was assessed using the DISCERN tool. Video content covering six aspects of myopia were evaluated. The impact of search strategies, video sample sizes, production properties, and myopia content on video quality and audience engagement was analyzed through single-factor or multi-factor analysis. RESULTS: DCS and MLS retrieval strategies, as well as varying sample sizes, resulted in differences in audience engagement for myopia videos (P < 0.039), while The DISCERN quality scores remained comparable (P > 0.221). Videos published by healthcare professionals (HCPs) and non-profit organizations (NPOs) were associated with high-quality (P ≤ 0.014) but comparatively lower popularity (P < 0.033). Videos that reported contents of risk factors, management, and outcomes showed high popularity (P < 0.018), while longer video duration (> 60s) exhibited the opposite trend (P < 0.032). Content on myopia evaluation (P ≤ 0.001) and management (P ≤ 0.022) and video duration were positively correlated with higher DISCERN quality. CONCLUSION: Videos created by HCPs and NPOs deserve greater attention. Rather than pursuing entertaining effects, professional educators should emphasize producing concise, and high-quality myopia content that readily resonates with the audience and has the potential to go viral on the platform.


Assuntos
Miopia , Gravação em Vídeo , Humanos , Miopia/terapia , Disseminação de Informação/métodos
11.
JAMA ; 331(10): 840-849, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38329440

RESUMO

Importance: It is uncertain whether intravenous methylprednisolone improves outcomes for patients with acute ischemic stroke due to large-vessel occlusion (LVO) undergoing endovascular thrombectomy. Objective: To assess the efficacy and adverse events of adjunctive intravenous low-dose methylprednisolone to endovascular thrombectomy for acute ischemic stroke secondary to LVO. Design, Setting, and Participants: This investigator-initiated, randomized, double-blind, placebo-controlled trial was implemented at 82 hospitals in China, enrolling 1680 patients with stroke and proximal intracranial LVO presenting within 24 hours of time last known to be well. Recruitment took place between February 9, 2022, and June 30, 2023, with a final follow-up on September 30, 2023. Interventions: Eligible patients were randomly assigned to intravenous methylprednisolone (n = 839) at 2 mg/kg/d or placebo (n = 841) for 3 days adjunctive to endovascular thrombectomy. Main Outcomes and Measures: The primary efficacy outcome was disability level at 90 days as measured by the overall distribution of the modified Rankin Scale scores (range, 0 [no symptoms] to 6 [death]). The primary safety outcomes included mortality at 90 days and the incidence of symptomatic intracranial hemorrhage within 48 hours. Results: Among 1680 patients randomized (median age, 69 years; 727 female [43.3%]), 1673 (99.6%) completed the trial. The median 90-day modified Rankin Scale score was 3 (IQR, 1-5) in the methylprednisolone group vs 3 (IQR, 1-6) in the placebo group (adjusted generalized odds ratio for a lower level of disability, 1.10 [95% CI, 0.96-1.25]; P = .17). In the methylprednisolone group, there was a lower mortality rate (23.2% vs 28.5%; adjusted risk ratio, 0.84 [95% CI, 0.71-0.98]; P = .03) and a lower rate of symptomatic intracranial hemorrhage (8.6% vs 11.7%; adjusted risk ratio, 0.74 [95% CI, 0.55-0.99]; P = .04) compared with placebo. Conclusions and Relevance: Among patients with acute ischemic stroke due to LVO undergoing endovascular thrombectomy, adjunctive methylprednisolone added to endovascular thrombectomy did not significantly improve the degree of overall disability. Trial Registration: ChiCTR.org.cn Identifier: ChiCTR2100051729.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Feminino , Humanos , Idoso , Método Duplo-Cego , Trombectomia/efeitos adversos , Hemorragias Intracranianas , Metilprednisolona/efeitos adversos
12.
Int J Mol Sci ; 25(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38474064

RESUMO

Our previous study has reported that metastasis-associated protein 2 (MTA2) plays essential roles in tumorigenesis and aggressiveness of gastric cancer (GC). However, the underlying molecular mechanisms of MTA2-mediated GC and its upstream regulation mechanism remain elusive. In this study, we identified a novel circular RNA (circRNA) generated from the MTA2 gene (circMTA2) as a crucial regulator in GC progression. CircMTA2 was highly expressed in GC tissues and cell lines, and circMTA2 promoted the proliferation, invasion, and metastasis of GC cells both in vitro and in vivo. Mechanistically, circMTA2 interacted with ubiquitin carboxyl-terminal hydrolase L3 (UCHL3) to restrain MTA2 ubiquitination and stabilize MTA2 protein expression, thereby facilitating tumor progression. Moreover, circMTA2 was mainly encapsulated and transported by exosomes to promote GC cell progression. Taken together, these findings uncover that circMTA2 suppresses MTA2 degradation by interacting with UCHL3, thereby promoting GC progression. In conclusion, we identified a cancer-promoting axis (circMTA2/UCHL3/MTA2) in GC progression, which paves the way for us to design and synthesize targeted inhibitors as well as combination therapies.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Proteínas Repressoras/genética , Linhagem Celular Tumoral , Histona Desacetilases/metabolismo , Proteólise , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genética , Ubiquitina Tiolesterase/metabolismo
13.
World J Microbiol Biotechnol ; 40(6): 181, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38668833

RESUMO

In view of the extensive potential applications of chitinase (ChiA) in various fields such as agriculture, environmental protection, medicine, and biotechnology, the development of a high-yielding strain capable of producing chitinase with enhanced activity holds significant importance. The objective of this study was to utilize the extracellular chitinase from Bacillus thuringiensis as the target, and Bacillus licheniformis as the expression host to achieve heterologous expression of ChiA with enhanced activity. Initially, through structural analysis and molecular dynamics simulation, we identified key amino acids to improve the enzymatic performance of chitinase, and the specific activity of chitinase mutant D116N/E118N was 48% higher than that of the natural enzyme, with concomitant enhancements in thermostability and pH stability. Subsequently, the expression elements of ChiA(D116N/E118N) were screened and modified in Bacillus licheniformis, resulting in extracellular ChiA activity reached 89.31 U/mL. Further efforts involved the successful knockout of extracellular protease genes aprE, bprA and epr, along with the gene clusters involved in the synthesis of by-products such as bacitracin and lichenin from Bacillus licheniformis. This led to the development of a recombinant strain, DW2△abelA, which exhibited a remarkable improvement in chitinase activity, reaching 145.56 U/mL. To further improve chitinase activity, a chitinase expression frame was integrated into the genome of DW2△abelA, resulting in a significant increas to 180.26 U/mL. Optimization of fermentation conditions and medium components further boosted shake flask enzyme activity shake flask enzyme activity, achieving 200.28 U/mL, while scale-up fermentation experiments yielded an impressive enzyme activity of 338.79 U/mL. Through host genetic modification, expression optimization and fermentation optimization, a high-yielding ChiA strain was successfully constructed, which will provide a solid foundation for the extracellular production of ChiA.


Assuntos
Bacillus licheniformis , Proteínas de Bactérias , Quitinases , Bacillus licheniformis/genética , Bacillus licheniformis/enzimologia , Bacillus thuringiensis/genética , Bacillus thuringiensis/enzimologia , Bacitracina , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Quitinases/biossíntese , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Simulação de Dinâmica Molecular , Família Multigênica , Proteínas Recombinantes/biossíntese , Temperatura
14.
Glia ; 71(3): 720-741, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36416239

RESUMO

Deficiency of glutamate transporter GLAST in Müller cells may be culpable for excessive extracellular glutamate, which involves in retinal ganglion cell (RGC) damage in glaucoma. We elucidated how GLAST was regulated in rat chronic ocular hypertension (COH) model. Western blot and whole-cell patch-clamp recordings showed that GLAST proteins and GLAST-mediated current densities in Müller cells were downregulated at the early stages of COH. In normal rats, intravitreal injection of the ephrinA3 activator EphA4-Fc mimicked the changes of GLAST in COH retinas. In purified cultured Müller cells, EphA4-Fc treatment reduced GLAST expression at mRNA and protein levels, which was reversed by the tyrosine kinase inhibitor PP2 or transfection with ephrinA3-siRNA (Si-EFNA3), suggesting that EphA4/ephrinA3 reverse signaling mediated GLAST downregulation. EphA4/ephrinA3 reverse signaling-induced GLAST downregulation was mediated by inhibiting PI3K/Akt/NF-κB pathways since EphA4-Fc treatment of cultured Müller cells reduced the levels of p-Akt/Akt and NF-κB p65, which were reversed by transfecting Si-EFNA3. In Müller cells with ephrinA3 knockdown, the PI3K inhibitor LY294002 still decreased the protein levels of NF-κB p65 in the presence of EphA4-Fc, and the mRNA levels of GLAST were reduced by LY294002 and the NF-κB inhibitor SN50, respectively. Pre-injection of the PI3K/Akt pathway activator 740 Y-P reversed the GLAST downregulation in COH retinas. Western blot and TUNEL staining showed that transfecting of Si-EFNA3 reduced Müller cell gliosis and RGC apoptosis in COH retinas. Our results suggest that activated EphA4/ephrinA3 reverse signaling induces GLAST downregulation in Müller cells via inhibiting PI3K/Akt/NF-κB pathways, thus contributing to RGC damage in glaucoma.


Assuntos
Efrina-A3 , Transportador 1 de Aminoácido Excitatório , Glaucoma , Hipertensão Ocular , Receptor EphA4 , Animais , Ratos , Sistema X-AG de Transporte de Aminoácidos , Regulação para Baixo , Células Ependimogliais , NF-kappa B , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Retina , Transportador 1 de Aminoácido Excitatório/metabolismo , Receptor EphA4/metabolismo , Efrina-A3/metabolismo
15.
Glia ; 71(6): 1502-1521, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36794533

RESUMO

Connexin43 (Cx43) is a major gap junction protein in glial cells. Mutations have been found in the gap-junction alpha 1 gene encoding Cx43 in glaucomatous human retinas, suggestive of the involvement of Cx43 in the pathogenesis of glaucoma. However, how Cx43 is involved in glaucoma is still unknown. We showed that increased intraocular pressure in a glaucoma mouse model of chronic ocular hypertension (COH) downregulated Cx43, which was mainly expressed in retinal astrocytes. Astrocytes in the optic nerve head where they gather and wrap the axons (optic nerve) of retinal ganglion cells (RGCs) were activated earlier than neurons in COH retinas and the alterations in astrocytes plasticity in the optic nerve caused a reduction in Cx43 expression. A time course showed that reductions of Cx43 expression were correlated with the activation of Rac1, a member of the Rho family. Co-immunoprecipitation assays showed that active Rac1, or the downstream signaling effector PAK1, negatively regulated Cx43 expression, Cx43 hemichannel opening and astrocyte activation. Pharmacological inhibition of Rac1 stimulated Cx43 hemichannel opening and ATP release, and astrocytes were identified to be one of the main sources of ATP. Furthermore, conditional knockout of Rac1 in astrocytes enhanced Cx43 expression and ATP release, and promoted RGC survival by upregulating the adenosine A3 receptor in RGCs. Our study provides new insight into the relationship between Cx43 and glaucoma, and suggests that regulating the interaction between astrocytes and RGCs via the Rac1/PAK1/Cx43/ATP pathway may be used as part of a therapeutic strategy for managing glaucoma.


Assuntos
Glaucoma , Hipertensão Ocular , Animais , Humanos , Camundongos , Trifosfato de Adenosina/metabolismo , Astrócitos/metabolismo , Conexina 43/genética , Conexina 43/metabolismo , Glaucoma/metabolismo , Glaucoma/patologia , Hipertensão Ocular/metabolismo , Quinases Ativadas por p21/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Células Ganglionares da Retina/metabolismo
16.
Stroke ; 54(6): 1569-1577, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37165864

RESUMO

BACKGROUND: The effect of imaging selection paradigms on endovascular thrombectomy outcomes in patients with acute ischemic stroke with large vessel occlusion remains uncertain. The study aimed to assess the effect of basic imaging (noncontrast computed tomography with or without computed tomographic angiography) versus advanced imaging (magnetic resonance imaging or computed tomography perfusion) on clinical outcomes following thrombectomy in patients with stroke with large vessel occlusion in the early and extended windows using a pooled analysis of patient-level data from 2 pivotal randomized clinical trials done in China. METHODS: This post hoc analysis used data from 1182 patients included in 2 multicenter, randomized controlled trials in China that evaluated adjunct therapies to endovascular treatment for acute ischemic stroke (Direct Endovascular Treatment for Large Artery Anterior Circulation Stroke performed from May 20, 2018, through May 2, 2020, and Intravenous Tirofiban Before Endovascular Treatment in Stroke from October 10, 2018, through October 31, 2021). Patients with occlusion of the intracranial internal carotid artery or proximal middle cerebral artery (M1/M2 segments) were categorized according to baseline imaging modality (basic versus advanced) as well as treatment time window (early, 0-6 hours versus extended, 6-24 hours from last known well to puncture). The primary outcome was the proportion of patients with functional independence (modified Rankin Scale score of 0-2) at 90 days. Multivariable Poisson regression analysis was performed to determine the association between imaging selection modality and outcomes after endovascular treatment at each time windows. RESULTS: A total of 1182 patients were included in this cohort analysis, with 648 in the early (471 with basic imaging versus 177 advanced imaging) and 534 in the extended (222 basic imaging versus 312 advanced imaging) time window. There were no differences in 90-day functional independence between the advanced and basic imaging groups in either time windows (early window: adjusted relative risk, 0.99 [95% CI, 0.84-1.16]; P=0.91; extended window: adjusted relative risk, 1.00 [95% CI, 0.84-1.20]; P=0.97). CONCLUSIONS: In this post hoc analysis of 2 randomized clinical trial pooled data involving patients with large vessel occlusion stroke, an association between imaging selection modality and clinical or safety outcomes for patients undergoing thrombectomy in either the early or extended windows was not detected. Our study adds to the growing body of literature on simpler imaging paradigms to assess thrombectomy eligibility across both the early and extended time windows. REGISTRATION: URL: http://www.chictr.org.cn; Unique identifiers: ChiCTR-IOR-17013568 and ChiCTR-INR-17014167.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Procedimentos Endovasculares/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
17.
Hematol Oncol ; 41(4): 704-717, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37186314

RESUMO

Chimeric antigen receptor (CAR)-reprogrammed T cell therapy is a novel and powerful treatment against hematological malignancies. Cytokine release syndrome (CRS) and other potentially life-threatening toxicities are known side effects which need appropriate management and supportive care. Coagulopathy is a common and severe CAR-T-related adverse event, while a comprehensive profile of coagulopathy in patients with multiple myeloma (MM) undergoing CAR-T cell therapy has not been reported. Therefore, we performed a comprehensive analysis of coagulopathy in 51 patients with r/r MM given anti-B cell maturation antigen CAR-T cell therapy. We found that 49% of patients had coagulation disorders, and 29% of patients experienced disseminated intravascular coagulation (DIC). Severe CRS, abnormal liver function and higher tumor burden were risk factors for the CAR-T-related coagulopathy. We found that the serum IL-6 level and alanine aminotransferase level were potential indicators for CAR-T-related DIC. Furthermore, we found that coagulation disorders occurred within 1 month after CAR-T cell infusion, mainly between days 10 and 13, which was 2-5 days later than the beginning of CRS and simultaneous with the beginning of abnormal liver function and the peak of CRS. In addition, although patients with coagulation dysfunction had a trend for better outcomes and prognosis, no statistical significance was found. In conclusion, our research provided a comprehensive understanding of CAR-T-related coagulopathy in MM. Upon timely and standardized treatment, coagulopathy was manageable in most cases.


Assuntos
Transtornos da Coagulação Sanguínea , Mieloma Múltiplo , Receptores de Antígenos Quiméricos , Humanos , Receptores de Antígenos Quiméricos/uso terapêutico , Mieloma Múltiplo/complicações , Mieloma Múltiplo/terapia , Estudos Retrospectivos , Antígeno de Maturação de Linfócitos B/uso terapêutico , Transtornos da Coagulação Sanguínea/terapia , Transtornos da Coagulação Sanguínea/complicações , Síndrome da Liberação de Citocina/etiologia
18.
J Nanobiotechnology ; 21(1): 162, 2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37211601

RESUMO

Large-scale skin damage brings potential risk to patients, such as imbalance of skin homeostasis, inflammation, fluid loss and bacterial infection. Moreover, multidrug resistant bacteria (MDRB) infection is still a great challenge for skin damage repair. Herein, we developed an injectable self-healing bioactive nanoglass hydrogel (FABA) with robust antibacterial and anti-inflammatory ability for normal and Methicillin-resistant Staphylococcus aureus (MRSA) infected skin wound repair. FABA hydrogel was fabricated facilely by the self-crosslinking of F127-CHO (FA) and alendronate sodium (AL)-decorated Si-Ca-Cu nanoglass (BA). FABA hydrogel could significantly inhibit the growth of Staphylococcus aureus, Escherichia coli and MRSA in vitro, while showing good cytocompatibility and hemocompatibility. In addition, FABA hydrogel could inhibit the expression of proinflammatory factor TNF-α and enhance the expression of anti-inflammatory factor IL-4/ IL-10. Based on its versatility, FABA hydrogel could complete wound closure efficiently (75% at day 3 for normal wound, 70% at day 3 for MRSA wound), which was almost 3 times higher than control wound, which was related with the decrease of inflammatory factor in early wound. This work suggested that FABA hydrogel could be a promising dressing for acute and MRSA-infected wound repair.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Humanos , Hidrogéis/farmacologia , Staphylococcus aureus , Alendronato , Antibacterianos/farmacologia , Escherichia coli
19.
BMC Pediatr ; 23(1): 586, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993819

RESUMO

BACKGROUND: Patients with complex phenotypes and a chromosomal translocation are particularly challenging, since several potentially pathogenic mechanisms need to be investigated. CASE PRESENTATION: Here, we combined exome and genome sequencing techniques to identify the precise breakpoints of heterozygous microduplications in the 6q25.3-q27 region and microdeletions in the 2q37.1-q37.3 region in a proband. The 5-year-old girl exhibited a severe form of congenital cranial dysinnervation disorder (CCDD) in addition to skeletal dysmorphism anomalies and severe intellectual disability. This is the second case affecting chromosomes 2q and 6q. The individual's karyotype showed an unbalanced translocation 46,XX,del(2)t(2;6)(q37.1;q25.3), which was inherited from her unaffected father [46,XY,t(2;6)(q37.1;q25.3)]. We also obtained the precise breakpoints of a de novo heterozygous copy number deletion [del(2)(q37.1q37.3)chr2:g.232963568_24305260del] and a copy number duplication [dup(6)(q25.3q27)chr6:g.158730978_170930050dup]. The parental origin of the observed balanced translocation was not clear because the parents declined genetic testing. CONCLUSION: Patients with a 2q37 deletion and 6q25.3 duplication may exhibit severe significant neurological and skeletal dysmorphisms, and the utilization of exome and genome sequencing techniques has the potential to unveil the entire translocation of the CNV and the precise breakpoint.


Assuntos
Anormalidades Múltiplas , Deleção Cromossômica , Feminino , Humanos , Pré-Escolar , Trissomia , Exoma , Anormalidades Múltiplas/genética , Translocação Genética
20.
Sensors (Basel) ; 23(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37447890

RESUMO

Mobile edge computing has been an important computing paradigm for providing delay-sensitive and computation-intensive services to mobile users. In this paper, we study the problem of the joint optimization of task assignment and energy management in a mobile-server-assisted edge computing network, where mobile servers can provide assisted task offloading services on behalf of the fixed servers at the network edge. The design objective is to minimize the system delay. As far as we know, our paper presents the first work that improves the quality of service of the whole system from a long-term aspect by prolonging the operational time of assisted mobile servers. We formulate the system delay minimization problem as a mixed-integer programming (MIP) problem. Due to the NP-hardness of this problem, we propose a dynamic energy criticality avoidance-based delay minimization ant colony algorithm (EACO), which strives for a balance between delay minimization for offloaded tasks and operational time maximization for mobile servers. We present a detailed algorithm design and deduce its computational complexity. We conduct extensive simulations, and the results demonstrate the high performance of the proposed algorithm compared to the benchmark algorithms.


Assuntos
Algoritmos , Benchmarking , Computadores , Dureza , Fenômenos Físicos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA