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1.
J Biol Chem ; 300(5): 107212, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522513

RESUMO

As an output effector of the Hippo signaling pathway, the TEAD transcription factor and co-activator YAP play crucial functions in promoting cell proliferation and organ size. The tumor suppressor NF2 has been shown to activate LATS1/2 kinases and interplay with the Hippo pathway to suppress the YAP-TEAD complex. However, whether and how NF2 could directly regulate TEAD remains unknown. We identified a direct link and physical interaction between NF2 and TEAD4. NF2 interacted with TEAD4 through its FERM domain and C-terminal tail and decreased the protein stability of TEAD4 independently of LATS1/2 and YAP. Furthermore, NF2 inhibited TEAD4 palmitoylation and induced the cytoplasmic translocation of TEAD4, resulting in ubiquitination and dysfunction of TEAD4. Moreover, the interaction with TEAD4 is required for NF2 function to suppress cell proliferation. These findings reveal an unanticipated role of NF2 as a binding partner and inhibitor of the transcription factor TEAD, shedding light on an alternative mechanism of how NF2 functions as a tumor suppressor through the Hippo signaling cascade.


Assuntos
Via de Sinalização Hippo , Neurofibromina 2 , Proteínas Serina-Treonina Quinases , Transdução de Sinais , Fatores de Transcrição de Domínio TEA , Humanos , Proliferação de Células , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Células HEK293 , Lipoilação , Neurofibromina 2/metabolismo , Neurofibromina 2/genética , Ligação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Estabilidade Proteica , Fatores de Transcrição de Domínio TEA/metabolismo , Proteínas Supressoras de Tumor , Ubiquitinação
2.
Carcinogenesis ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829328

RESUMO

Cancer cells exhibit heterogenous metastatic potential, and high metastatic subclones can enhance metastatic potential of low metastatic subclones by transmitting some factors. Exosomal miRNAs play a pivotal role in the crosstalk of heterogenous metastatic subclones. This study discovered that miR-20a-3p was upregulated in colorectal adenocarcinoma (CRA), correlated with metastasis, and potentially served as a prognostic indicator for CRA. miR-20a-3p could promote the proliferation, migration and invasion of CRA cells. Interestingly, high metastatic CRA cells could promote malignant phenotypes of low metastatic CRA cells by transmitting exosomal miR-20a-3p. Mechanically, miR-20a-3p could inhibit NF1, thereby activate the RAS-mediated mitogen-activated protein kinases (MAPK) signaling pathway to drive the metastasis of CRA. In summary, our study provided the evidence that colorectal cancer cells with high metastatic potential drive metastasis by transmitting exosomal miR-20a-3p through modulating NF1/MAPK pathway.

3.
Opt Express ; 32(9): 15156-15165, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859174

RESUMO

Fiber side-pump couplers can enhance the output power of fiber laser due to their dependable and efficient operation and impressive power handling capability. We developed a tellurite fiber side-pump coupler by twisting and fusing a tapered pump fiber onto a target fiber. The effect of twisting parameters on coupling efficiency was comprehensively investigated through theoretical simulations and experiments. Experimental results exhibited an impressive coupling efficiency of 76.5% and a root mean square stability of 0.086% and 0.091% before and after one month, respectively, driven by an incident pump power of up to 4.2 W.

4.
Opt Lett ; 49(9): 2509-2512, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691756

RESUMO

A high-efficiency and broadband tunable chalcogenide fiber Raman laser with the Fabry-Perot (F-P) cavity formed by the Fresnel reflection was established. A maximum average power slope efficiency of around 43% and a maximum output peak power of about 2.9 W at 2148 nm were demonstrated by using a 2 µm nanosecond pump source. The laser shows a broadened pulse width of 674 ns and a broadband tunability of the central wavelength from 2100 to 2186 nm. The Raman Fabry-Perot cavity constituted by the Fresnel reflection from chalcogenide fiber endfaces can operate at any wavelength without the aid of any additional optical feedback element. This will facilitate the realization of fiber lasers with excellent performance and compact system, especially in the mid-infrared region.

5.
Exp Eye Res ; 240: 109814, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307190

RESUMO

Neurotrophic keratopathy (NK) is a challenging disease with the reduced innervation to the cornea. To establish a genetic and stable mouse model of NK, we utilized the TRPV1-DTR mice with intraperitoneal injection of diphtheria toxin (DT) to selectively eliminate TRPV1 neurons. After DT administration, the mice exhibited robust ablation of TRPV1 neurons in the trigeminal ganglion, accompanied with reduced corneal sensation and nerve density, as well as the decreased calcitonin-gene-related peptide (CGRP) and substance P levels. According to disease progression of TRPV1 neuronal ablation, tear secretion was reduced from day 3, which followed by corneal epithelial punctate lesions from day 7. From day 11 to day 16, the mice exhibited persistent corneal epithelial defects and stromal edema. By day 21, corneal ulceration and stromal melting were observed with the abundant inflammatory cell infiltration, corneal neovascularization, and enhanced cell apoptosis. Moreover, subconjunctival injection of CGRP delayed the NK progression with the characteristics of reduced severe corneal epithelial lesions and corneal inflammation. In addition, the impairments of conjunctival goblet cells, lacrimal gland, and meibomian gland were identified by the diminished expression of MUC5AC, AQP5, and PPARγ, respectively. Therefore, these results suggest that the TRPV1-DTR mice may serve as a reliable animal model for the research of NK pathogenesis.


Assuntos
Distrofias Hereditárias da Córnea , Ceratite , Doenças do Nervo Trigêmeo , Camundongos , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Córnea/metabolismo , Neurônios/metabolismo , Modelos Animais de Doenças , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo
6.
Environ Res ; 252(Pt 3): 118972, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38657851

RESUMO

This study aims to provide a thorough characterization of dissolved organics in oil sands process water (OSPW) in field-based aquatic mesocosms at both molecular and bulk measurement levels using multiple analytical methods. In a 3-year outdoor mesocosm experiment, the analysis of naphthenic acid (NA) species was conducted using ultra-performance liquid chromatography time-of-flight mass spectrometry (UPLC-TOFMS). The results revealed the removal of both total NAs (38% and 35%) and classical NAs (O2-NAs, 58% and 49%) in undiluted and half-diluted OSPW, respectively. The increased ratios of oxidized NAs (O3-O6 NAs) to classical NAs suggested a transformation trend. The results also indicated that O2-NAs with higher carbon number and lower double bond equivalent (DBE) were more easily degraded in the mesocosm systems. Biomimetic extraction using solid-phase microextraction (BE-SPME) measurement displayed 26% (undiluted OSPW) and 30% (half-diluted OSPW) decrease in total bioavailable organics over 3 years. Naphthenic acids fraction compounds (NAFCs) obtained by liquid-liquid extraction (LLE) were also determined using Fourier transform infrared spectroscopy (FTIR). Reduction in acute toxicity for undiluted (43%) and half-diluted (26%) OSPW was observed over 3 years, which are well correlated with the decreases of NAs and BE-SPME concentrations. Moreover, BE-SPME values were found to be linearly correlated with total NAs concentrations (r = 0.96) and NAFCs (r = 0.96). Additionally, the linear relationships of individual O2-O6 NA species and BE-SPME concentrations unveiled the changes in the relative abundances of O2-O6 NA species in total bioavailable organics over time in the mesocosms. The present study has provided comprehensive insights by integrating various analytical methods, contributing valuable information for assessing the effectiveness of aquatic mesocosm systems in studying the temporal changes of organics in OSPW.


Assuntos
Campos de Petróleo e Gás , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Campos de Petróleo e Gás/química , Ácidos Carboxílicos/análise , Microextração em Fase Sólida/métodos , Espectrometria de Massas/métodos
7.
Ecotoxicol Environ Saf ; 270: 115878, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38150748

RESUMO

Aluminum (Al) exposure has been linked to the development of a variety of neurodegenerative diseases. However, whether m6A RNA methylation participated in Al-induced neurotoxicity remain to be defined. In this study, mice were administrated with aluminum-lactate at dose of 220 mg/kg. bw by gavage for 3 months. Meanwhile, the primary hippocampal neurons were isolated and treated with 0, 50, 100, 150 µM aluminum-lactate, respectively for 7 days. Al exposure caused neuronal shrinkage, decreased Nissl bodies, and increased apoptosis. In accordance, in vitro studies also showed that Al exposure led to neuronal apoptosis in a dose-dependent manner, together with the decline in m6A RNA methylation levels. Moreover, the mRNA expression of Mettl3, Mettl14, Fto, and Ythdf2 were decreased upon Al exposure. Notably, the protein expression of METTL3 was dramatically down-regulated by 42% and 35% in Al-treated mice and neurons, suggesting METTL3 might exert a crucial role in Al-induced neurotoxicity. We next established a mouse model with hippocampus-specific overexpressing of Mettl3 gene to confirm the regulatory role of RNA methylation and found that METTL3 overexpression relieved the neurological injury induced by Al. The integrated MeRIP-seq and RNA-seq analysis elucidated that 631 genes were differentially expressed at both m6A RNA methylation and mRNA expression. Notably, EGFR tyrosine kinase inhibitor resistance, Rap1 signaling pathway, protein digestion and absorption might be involved in Al-induced neurotoxicity. Moreover, VEGFA, Thbs1, and PDGFB might be the central molecules. Collectively, our findings provide the novel sight into the role of m6A RNA methylation in neurodegenerative disease induced by Al.


Assuntos
Alumínio , Doenças Neurodegenerativas , Camundongos , Animais , Alumínio/toxicidade , Alumínio/metabolismo , Metilação de RNA , Metiltransferases/genética , Metiltransferases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Lactatos , RNA/metabolismo
8.
Am J Transplant ; 23(11): 1694-1708, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37507072

RESUMO

The classical lytic infection theory along with large T antigen-mediated oncogenesis cannot explain the BK polyomavirus (BKPyV)-associated tumor secondary to BKPyV-associated nephropathy (BKVAN), viremia/DNAemia, and viruria after renal transplantation. This study performed virome capture sequencing and pathological examination on regularly collected urine sediment and peripheral blood samples, and BKVAN and tumor biopsy tissues of 20 patients with BKPyV-associated diseases of different stages. In the early noncancerous stages, well-amplified integration sites were visualized by in situ polymerase chain reaction, simultaneously with BKPyV inclusion bodies and capsid protein expression. The integration intensity, the proportion of microhomology-mediated end-joining integration, and host PARP-1 and POLQ gene expression levels increased with disease progression. Furthermore, multiomics analysis was performed on BKPyV-associated urothelial carcinoma tissues, identifying tandem-like structures of BKPyV integration using long-read genome sequencing. The carcinogenicity of BKPyV integration was proven to disturb host gene expression and increase viral oncoprotein expression. Fallible DNA double-strand break repair pathways were significantly activated in the parenchyma of BKPyV-associated tumors. Olaparib showed an antitumor activity dose-response effect in the tumor organoids without BRCA1/2 genes mutation. In conclusion, the dynamic viral integration patterns actively participate in the progression of BKPyV-associated diseases and thus could be a potential target for disease monitoring and intervention.


Assuntos
Vírus BK , Carcinoma de Células de Transição , Transplante de Rim , Nefrite Intersticial , Infecções por Polyomavirus , Infecções Tumorais por Vírus , Neoplasias da Bexiga Urinária , Humanos , Transplante de Rim/efeitos adversos , Vírus BK/genética , Proteína BRCA1/genética , Proteína BRCA2/genética , Integração Viral , Infecções Tumorais por Vírus/etiologia
9.
Clin Gastroenterol Hepatol ; 21(3): 681-693, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35337983

RESUMO

BACKGROUND & AIMS: Acute-on-chronic liver failure (ACLF) is a life-threatening syndrome with rapid progression. This study aimed to develop and validate a prognostic score to predict the onset of ACLF in hepatitis B virus (HBV) etiology. METHODS: The prospective clinical data of 1373 patients with acute deterioration of HBV-related chronic liver disease were used to identify clinical characteristics and develop a prognostic score for the onset of ACLF. RESULTS: Of the patients assessed using the Chinese Group on the Study of Severe Hepatitis B (COSSH)-ACLF criteria, 903 patients with non-ACLF at admission (1 received transplantation at 5 days) were stratified: 71 with progression to ACLF and 831 without progression to ACLF at 7 days. Four predictors (total bilirubin, international normalized ratio, alanine aminotransferase, and ferritin) were associated significantly with ACLF onset at 7 days. The COSSH-onset-ACLF score was constituted as follows: (0.101 × ln [alanine aminotransferase] + 0.819 × ln [total bilirubin] + 2.820 × ln [international normalized ratio] + 0.016 × ln [ferritin]). The C-indexes of the new score for 7-/14-/28-day onset (0.928/0.925/0.913) were significantly higher than those of 5 other scores (Chronic Liver Failure Consortium ACLF development score/Model for End-stage Liver Disease score/Model for End-stage Liver Disease sodium score/COSSH-ACLF score/Chronic liver failure Consortium ACLF score; all P < .001). The improvement in predictive errors, time-dependent receiver operating characteristic, probability density function evaluation, and calibration curves of the new score showed the highest predictive value for ACLF onset at 7/14/28 days. Risk stratification of the new score showed 2 strata with high and low risk (≥6.3/<6.3) of ACLF onset. The external validation group further confirmed the earlier results. CONCLUSIONS: A new prognostic score based on 4 predictors can accurately predict the 7-/14-/28-day onset of ACLF in patients with acute deterioration of HBV-related chronic liver disease and might be used to guide clinical management.


Assuntos
Insuficiência Hepática Crônica Agudizada , Doença Hepática Terminal , Hepatite B Crônica , Hepatite B , Humanos , Vírus da Hepatite B , Doença Hepática Terminal/complicações , Hepatite B Crônica/complicações , Insuficiência Hepática Crônica Agudizada/complicações , Estudos Prospectivos , Alanina Transaminase , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença , Hepatite B/complicações , Bilirrubina , Curva ROC
10.
Anal Chem ; 95(42): 15540-15548, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37831785

RESUMO

With the development of near-infrared II (NIR-II) fluorescence imaging, Ag2Se quantum dots (QDs) have become promising label candidates due to their negligible toxicity and narrow band gap. Despite their potential for gastrointestinal (GI) imaging, the application of Ag2Se QDs still presents significant challenges due to issues such as fluorescence extinction or poor stability in the complex digestive microenvironment. Herein, we have proposed a novel approach to the continuous production of Se precursors using glutathione (GSH) as the reductant under acidic conditions, realizing the continuous growth of water-dispersible Ag2Se QDs. The Ag2Se QDs emitting at 600-1100 nm have been successfully synthesized. Meanwhile, the silver-rich surface of the synthesized NIR-II Ag2Se QDs has been passivated well with the dense GSH, resulting in exceptional colloidal stability and photostability and endowing them with acid resistance. As a result, the obtained NIR-II Ag2Se QDs have exhibited remarkable stability in gastric acid, thus enabling their utilization for long-term real-time monitoring of GI peristalsis via NIR-II fluorescence imaging. Moreover, in contrast to conventional barium meal-based X-ray imaging, NIR-II fluorescence imaging with as-prepared NIR-II Ag2Se QDs can offer clearer visualization of fine intestinal structures, with a width as small as 1.07 mm. The developed strategy has offered a new opportunity for the synthesis of acid-resistant nanocrystals, and the acid-resistant, low-toxicity, and biocompatible NIR-II Ag2Se QDs synthesized in this work show a great promise for GI imaging and diagnosis of GI diseases in vivo.


Assuntos
Nanopartículas , Pontos Quânticos , Pontos Quânticos/toxicidade , Pontos Quânticos/química , Nanopartículas/química , Fluorescência , Prata/química
11.
Biochem Biophys Res Commun ; 678: 11-16, 2023 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-37603968

RESUMO

Ferroptosis is a non-apoptotic form of cell death, involved in chronic kidney diseases (CKD) and acute kidney injury (AKI), so far, the role of ferroptosis in focal segmental glomerulosclerosis (FSGS) remains largely unknown. We aimed to investigate the role of ferroptosis in FSGS, in this study, we found the reduced expression of GPX4 in podocytes, as well as tubular epithelial cells (TECs), from patients with FSGS. Treatment with ferrostatin-1 (Fer-1), a potent and selective ferroptosis inhibitor, significantly reduced proteinuria, prevented glomerulosclerosis, attenuated podocyte injury in ADR-induced FSGS murine model. As expected, ADR treatment caused downregulation of GPX4 in human podocytes, treatment with Fer-1 greatly blocked the downregulation of GPX4, restored the GSH level and attenuated cell death. Furthermore, Fer-1 treatment greatly delayed the development of tubulointerstitial fibrosis in ADR-induced FSGS murine model. Taken together, ferroptosis is involved in the pathogenesis of FSGS, targeting ferroptosis is a promising therapeutic option for patients with FSGS.


Assuntos
Injúria Renal Aguda , Ferroptose , Glomerulosclerose Segmentar e Focal , Podócitos , Humanos , Animais , Camundongos , Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Modelos Animais de Doenças , Fibrose
12.
BMC Plant Biol ; 23(1): 215, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37098482

RESUMO

BACKGROUND: Melatonin is considered to be a polyfunctional master regulator in animals and higher plants. Exogenous melatonin inhibits plant infection by multiple diseases; however, the role of melatonin in Cucumber green mottle mosaic virus (CGMMV) infection remains unknown. RESULTS: In this study, we demonstrated that exogenous melatonin treatment can effectively control CGMMV infection. The greatest control effect was achieved by 3 days of root irrigation at a melatonin concentration of 50 µM. Exogenous melatonin showed preventive and therapeutic effects against CGMMV infection at early stage in tobacco and cucumber. We utilized RNA sequencing technology to compare the expression profiles of mock-inoculated, CGMMV-infected, and melatonin+CGMMV-infected tobacco leaves. Defense-related gene CRISP1 was specifically upregulated in response to melatonin, but not to salicylic acid (SA). Silencing CRISP1 enhanced the preventive effects of melatonin on CGMMV infection, but had no effect on CGMMV infection. We also found exogenous melatonin has preventive effects against another Tobamovirus, Pepper mild mottle virus (PMMoV) infection. CONCLUSIONS: Together, these results indicate that exogenous melatonin controls two Tobamovirus infections and inhibition of CRISP1 enhanced melatonin control effects against CGMMV infection, which may lead to the development of a novel melatonin treatment for Tobamovirus control.


Assuntos
Melatonina , Tobamovirus , Reguladores de Crescimento de Plantas , Cisteína , Melatonina/farmacologia , Tobamovirus/genética , Nicotiana/genética , Doenças das Plantas/genética
13.
Mol Carcinog ; 62(7): 1001-1008, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37067398

RESUMO

Mutations in epidermal growth factor receptor and anaplastic lymphoma kinase are common driver events in non-small cell lung cancer (NSCLC), which are associated with a high frequency of bone metastases (BMs). While the bone marrow represents a specialized immune microenvironment, the immune repertoire of BMs remains unknown. Considering the higher incidence of BMs in driver gene-positive NSCLCs, and the unique biology of the bone, herein, we assessed the infiltrating immune cells and T cell receptor (TCR) profile of BMs in driver-positive NSCLCs. Immune profile of BMs in driver gene-positive NSCLC were assessed in 10 patients, where 6 had driver gene-positive mutation. TCR and bulk RNA sequencing were performed on malignant bone samples. The diversity and clonality of the TCR repertoire were analyzed. The cellular components were inferred from bulk gene expression profiles computationally by CIBERSORT. Although BMs were generally regarded as immune-cold tumors, immune cell composition analyses showed co-existence of cytotoxic and suppressor immune cells in driver-positive BM samples, as compared to primary lung. Analysis of the TCR repertoire indicated a trend of higher diversity and similar clonality in the driver-positive compared with the driver-negative subsets. In addition, we identified two cases that showed the opposite response to immune checkpoint blockade. A comparison of these two patients' BM samples showed more highly amplified clones, fewer M2 macrophages and more activated natural killer cells in the responder. In summary, BMs in NSCLC are heterogeneous in their immune microenvironment, which might be related to differential clinical outcomes to immune checkpoint blockade.


Assuntos
Neoplasias Ósseas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Pulmão/patologia , Neoplasias Ósseas/genética , Receptores de Antígenos de Linfócitos T/genética , Microambiente Tumoral/genética
14.
Opt Express ; 31(2): 2394-2401, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785254

RESUMO

We demonstrated a compact self-starting nanosecond Yb:YAG/V:YAG solid-state laser with cylindrical vector beams output modulated by the intracavity mode converter S-waveplate experimentally. We can deliver the stable Q-switched pulse with the highest repetition rate 3.61 kHz and minimum pulse width 26 ns at the wavelength of 1030.07 nm with the help of the V:YAG crystal. In addition, the switchable radially and azimuthally polarized beams can be realized with polarization extinction ratios of 92.3% and 89.6%, respectively. The compact laser configuration can provide solutions for generating stable nanosecond structured light, and may benefit the applications like micro/nano material processing.

15.
Opt Express ; 31(8): 13169-13181, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37157460

RESUMO

In this study, (1 + 1) × 1 side-pump couplers made of tellurite fibers were fabricated and investigated. The whole optical design of the coupler was established on the basis of ray tracing models and validated by experimental results. By optimizing the preparation conditions and structural parameters, the tested component achieved a coupling efficiency of 67.52% and an insertion loss of 0.52 dB. To the best of our knowledge, this is the first time a tellurite-fiber-based side-pump coupler was developed. The fused coupler presented will simplify many mid-infrared fiber lasers or amplifier architectures.

16.
Opt Lett ; 48(15): 4057-4060, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37527117

RESUMO

A stable mid-infrared saturable absorber with a high damage threshold is urgently required for high-performance optical modulation in the mid-infrared regime. Here, we demonstrate stable mid-infrared erbium-doped fiber laser generation modulated by tantalum carbide nanoparticles (TaC NPs) experimentally. The TaC NPs show high physicochemical stability, obvious nonlinear optical absorption, and a high damage threshold. By introducing the TaC-based saturable absorber into an erbium-doped fiber laser, stable nanosecond pulses can be successfully delivered with a minimum pulse duration of 575 ns and signal-to-noise ratio of over 40 dB. The experimental results show that TaC NPs can act as a stable mid-infrared pulse modulator, and may make inroads for developing highly stable broadband optoelectronic devices.

17.
Neurochem Res ; 48(3): 767-780, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36418652

RESUMO

Spinal cord injury (SCI) is a serious injury to the central nervous system that causes significant physical and psychological trauma to the patient. SCI includes primary spinal cord injuries and secondary spinal cord injuries. The secondary injury refers to the pathological process or reaction after the primary injury. Although SCI has always been thought to be an incurable injury, the human nerve has the ability to repair itself after an injury. However, the reparability is limited because glial scar formation impedes functional recovery. There is a type of astrocyte that can differentiate into two forms of reactive astrocytes known as 'A1' and 'A2' astrocytes. A1 astrocytes release cytotoxic chemicals that cause neurons and oligodendrocytes to die and perform a harmful role. A2 astrocytes can produce neurotrophic factors and act as neuroprotectors. This article discusses ways to block A1 astrocytes while stimulating A2 astrocytes to formulate a new treatment for spinal cord injury.


Assuntos
Astrócitos , Traumatismos da Medula Espinal , Humanos , Astrócitos/patologia , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/patologia , Neurônios/patologia , Gliose/patologia , Sistema Nervoso Central , Medula Espinal/patologia
18.
Bioorg Med Chem ; 93: 117455, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37643500

RESUMO

Human sirtuin 5 (SIRT5) participates in a variety of metabolic disorder-associated diseases, including cancer. Inhibition of SIRT5 has been confirmed to provide a new strategy for treatment of related diseases. Previously, we discovered a pyrimidine skeleton inhibitor XIV, which showed low micromolar inhibitory activity against SIRT5. Herein, we utilized the scaffold-hopping strategy to design and synthesize a series of 2,4,6- trisubstituted triazine derivatives. The SAR analysis led to the discovery of several new SIRT5 inhibitors with low micromolar inhibition levels. The most potent compounds 10 (IC50 = 5.38 µM), and 14 (IC50 = 4.07 µM) were further confirmed to be the substrate-competitive SIRT5 inhibitors through enzyme kinetic assays, which is consistent with the molecular docking analyses. Fluorescence-based thermal shift assays proved that these compounds may stabilize SIRT5 by binding withprotein.. In addition, compounds 10 and 14 were also revealed to have moderate selectivity to SIRT5 over SIRT1-3. This study will aid further efforts to develop highly potent and selective SIRT5 inhibitors for the treatment of cancer and other related diseases.


Assuntos
Compostos Radiofarmacêuticos , Sirtuínas , Humanos , Simulação de Acoplamento Molecular , Bioensaio , Ensaios Enzimáticos , Triazinas/farmacologia
19.
Methods ; 202: 117-126, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34274447

RESUMO

Epilepsy is a neurological disorder that affects approximately 1% of the world's populations. Epilepsy prediction has been of great interest as it can identify and warn of an upcoming seizure, and to reduce the burden of the unpredictability of seizures. In this paper, we proposed a new seizure prediction model, TASM_ResNet, based on a time-wise attention simulation module and a pre-trained ResNet, using intracranial EEG signals. The simulation module with a time-wise attention was designed to convert EEG data into image like data and extract temporal features from raw data. Pre-trained ResNet was applied to reduce the amount of training data without initial training. Moreover, since the data is extremely imbalanced, we used an improved focal loss (FL) instead of the cross-entropy loss and investigated the optimal parameters for FL. Compared with a state-of-art CNN model, our proposed model achieved a better average AUC of 0.877. Moreover, our results demonstrated that EEG signals can be migrated to the image network which was pre-trained on large data set through a simulation module.


Assuntos
Eletroencefalografia , Epilepsia , Algoritmos , Atenção , Eletroencefalografia/métodos , Epilepsia/diagnóstico , Humanos , Convulsões/diagnóstico
20.
Brain ; 145(5): 1839-1853, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34919654

RESUMO

CACNA1I is implicated in the susceptibility to schizophrenia by large-scale genetic association studies of single nucleotide polymorphisms. However, the channelopathy of CACNA1I in schizophrenia is unknown. CACNA1I encodes CaV3.3, a neuronal voltage-gated calcium channel that underlies a subtype of T-type current that is important for neuronal excitability in the thalamic reticular nucleus and other regions of the brain. Here, we present an extensive functional characterization of 57 naturally occurring rare and common missense variants of CACNA1I derived from a Swedish schizophrenia cohort of more than 10 000 individuals. Our analysis of this allelic series of coding CACNA1I variants revealed that reduced CaV3.3 channel current density was the dominant phenotype associated with rare CACNA1I coding alleles derived from control subjects, whereas rare CACNA1I alleles from schizophrenia patients encoded CaV3.3 channels with altered responses to voltages. CACNA1I variants associated with altered current density primarily impact the ionic channel pore and those associated with altered responses to voltage impact the voltage-sensing domain. CaV3.3 variants associated with altered voltage dependence of the CaV3.3 channel and those associated with peak current density deficits were significantly segregated across affected and unaffected groups (Fisher's exact test, P = 0.034). Our results, together with recent data from the SCHEMA (Schizophrenia Exome Sequencing Meta-Analysis) cohort, suggest that reduced CaV3.3 function may protect against schizophrenia risk in rare cases. We subsequently modelled the effect of the biophysical properties of CaV3.3 channel variants on thalamic reticular nucleus excitability and found that compared with common variants, ultrarare CaV3.3-coding variants derived from control subjects significantly decreased thalamic reticular nucleus excitability (P = 0.011). When all rare variants were analysed, there was a non-significant trend between variants that reduced thalamic reticular nucleus excitability and variants that either had no effect or increased thalamic reticular nucleus excitability across disease status. Taken together, the results of our functional analysis of an allelic series of >50 CACNA1I variants in a schizophrenia cohort reveal that loss of function of CaV3.3 is a molecular phenotype associated with reduced disease risk burden, and our approach may serve as a template strategy for channelopathies in polygenic disorders.


Assuntos
Canais de Cálcio Tipo T , Canalopatias , Esquizofrenia , Alelos , Canais de Cálcio Tipo T/genética , Canalopatias/genética , Humanos , Mutação de Sentido Incorreto , Esquizofrenia/genética , Suécia
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