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1.
Int J Mol Sci ; 24(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37958543

RESUMO

Reactive oxygen species (ROS) are an important part of adaptation to biotic and abiotic stresses and regulate seed germination through positive or negative signaling. Seed adaptation to abiotic stress may be mediated by hydrogen peroxide (H2O2). The effects of the ROS scavenger N,N'-dimethylthiourea (DMTU) on maize seed germination through endogenous H2O2 regulation is unclear. In this study, we investigated the effects of different doses of DMTU on seed endogenous H2O2 and radicle development parameters using two maize varieties (ZD958 and DMY1). The inhibitory effect of DMTU on the germination rate and radicle growth was dose-dependent. The inhibitory effect of DMTU on radicle growth ceased after transferring maize seeds from DMTU to a water medium. Histochemical analyses showed that DMTU eliminated stable H2O2 accumulation in the radicle sheaths and radicles. The activity of antioxidant enzyme and the expression of antioxidant enzyme-related genes (ZmAPX2 and ZmCAT2) were reduced in maize seeds cultured with DMTU compared with normal culture conditions (0 mmol·dm-3 DMTU). We suggest the use of 200 mmol·dm-3 DMTU as an H2O2 scavenger to study the ROS equilibrium mechanisms during the germination of maize seeds, assisting in the future with the efficient development of plant growth regulators to enhance the seed germination performance of test maize varieties under abiotic stress.


Assuntos
Antioxidantes , Germinação , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/farmacologia , Sementes , Zea mays , Oxigênio/farmacologia , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/metabolismo
2.
Zhongguo Gu Shang ; 36(9): 849-53, 2023 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-37735077

RESUMO

OBJECTIVE: To analyze the important effect of 3D printing personalized lumbar support on lumbar pain and lumbar function in patients with lumbar disc herniation. METHODS: From October 2018 to May 2021, 60 patients initially diagnosed with lumbar disc herniation were selected and divided into an observation group and a control group, with 30 patients in each group. Among them, there were 18 males and 12 females in the observation group;the age ranged from 24 to 56 years old, with an average of (45.23±6.07) years old. The course of disease ranged from 1 to 24 months, with an average of(6.25±0.82) months, and rehabilitation treatment was carried out by wearing 3D printed personalized lumbar support. There were 19 males and 11 females in the control group;the age ranged from 25 to 57 years old, with an average of (42.78±7.58) years old. The course of disease ranged from 1 to 24 months, with an average of (6.72±1.36) months, and rehabilitation treatment is carried out by wearing traditional lumbar protective equipment. The Japanese Orthopaedic Association (JOA) scores, lumbar Oswestry dysfunction index (ODI) and visual analogue scale (VAS) were evaluated and compared between the two groups before and 1 course after treatment (3 weeks). RESULTS: There was no statistically significant difference in JOA, ODI, and VAS between two groups before treatment (P>0.05). After one course of treatment (3 weeks), JOA scores of both groups was increased compared to before treatment (P<0.05), while ODI and VAS decreased compared to before treatment (P<0.05). After treatment, JOA score of observation group was higher than that of control group (P<0.05), while ODI and VAS scores were lower than those of control group. No adverse events occurred in both groups. CONCLUSION: The application of 3D printing personalized lumbar support can effectively alleviate the pain of patients with lumbar disc herniation and improve their lumbar function of patients.


Assuntos
Deslocamento do Disco Intervertebral , Dor Lombar , Ortopedia , Feminino , Masculino , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Deslocamento do Disco Intervertebral/cirurgia , Impressão Tridimensional , Tecnologia
3.
RNA Biol ; 20(1): 311-322, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37294214

RESUMO

The exon junction complex (EJC) plays key roles throughout the lifespan of RNA and is particularly relevant in the nervous system. We investigated the roles of two EJC members, the paralogs MAGOH and MAGOHB, with respect to brain tumour development. High MAGOH/MAGOHB expression was observed in 14 tumour types; glioblastoma (GBM) showed the greatest difference compared to normal tissue. Increased MAGOH/MAGOHB expression was associated with poor prognosis in glioma patients, while knockdown of MAGOH/MAGOHB affected different cancer phenotypes. Reduced MAGOH/MAGOHB expression in GBM cells caused alterations in the splicing profile, including re-splicing and skipping of multiple exons. The binding profiles of EJC proteins indicated that exons affected by MAGOH/MAGOHB knockdown accumulated fewer complexes on average, providing a possible explanation for their sensitivity to MAGOH/MAGOHB knockdown. Transcripts (genes) showing alterations in the splicing profile are mainly implicated in cell division, cell cycle, splicing, and translation. We propose that high MAGOH/MAGOHB levels are required to safeguard the splicing of genes in high demand in scenarios requiring increased cell proliferation (brain development and GBM growth), ensuring efficient cell division, cell cycle regulation, and gene expression (splicing and translation). Since differentiated neuronal cells do not require increased MAGOH/MAGOHB expression, targeting these paralogs is a potential option for treating GBM.


Assuntos
Genes cdc , Glioblastoma , Humanos , Splicing de RNA , Divisão Celular , Núcleo Celular/metabolismo , Glioblastoma/metabolismo , Proteínas Nucleares/metabolismo
4.
ACS Nano ; 17(11): 10181-10190, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37212535

RESUMO

Modern infrared (IR) microscopy, communication, and sensing systems demand control of the spectral characteristics and polarization states of light. Typically, these systems require the cascading of multiple filters, polarization optics, and rotating components to manipulate light, inevitably increasing their sizes and complexities. Here, we report two-terminal mid-infrared (mid-IR) emitters, in which tuning the polarity of the applied bias can switch their emission peak wavelengths and linear polarization states along two orthogonal orientations. Our devices are composed of two back-to-back p-n junctions formed by stacking anisotropic light-emitting materials, black phosphorus and black arsenic-phosphorus with MoS2. By controlling the crystallographic orientations and engineering the band profile of heterostructures, the emissions of two junctions exhibit distinct spectral ranges and polarization directions; more importantly, these two electroluminescence (EL) units can be independently activated, depending on the polarity of the applied bias. Furthermore, we show that when operating our emitter under the polarity-switched pulse mode, the time-averaged EL exhibits the characteristics of broad spectral coverage, encompassing the entire first mid-IR atmospheric window (λ: 3-5 µm), and electrically tunable spectral shapes.

5.
ACS Appl Mater Interfaces ; 14(28): 32665-32674, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35797527

RESUMO

A bias-selectable photodetector, which can sense the wavelength of interest by tuning the polarity of applied bias, is useful for target discrimination and identification applications. So far, those detectors are generally based on the back-to-back photodiode configuration via exploiting epitaxial semiconductors as optoelectronic materials, which inevitably lead to high fabrication costs and complex device architectures. Here, we demonstrate that our band-engineered van der Waals heterostructures can be applied as bias-selectable photodetectors. Our first prototypical device is mainly composed of black phosphorus (BP) and MoTe2 light absorbers sandwiching a thin MoS2 hole blocking layer. By varying the bias polarity, its spectral photoresponse can be switched between near-infrared and short-wave infrared bands, and our optoelectronic characterizations indicate that the detector can exhibit high external quantum efficiency (EQE) and fast operation speed. With this framework, we further demonstrate the detector with bias-selectable photoresponses within the mid-wave infrared band using BP/MoS2/arsenic-doped BP heterostructures and show that our developed detectors can be integrated into a single-pixel imaging system to capture dual-band infrared imaging.

6.
Nat Nanotechnol ; 17(7): 721-728, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35501377

RESUMO

Electrical manipulation of the valley degree of freedom in transition metal dichalcogenides is central to developing valleytronics. Towards this end, ferromagnetic contacts, such as Ga(Mn)As and permalloy, have been exploited to inject spin-polarized carriers into transition metal dichalcogenides to realize valley-dependent polarization. However, these materials require either a high external magnetic field or complicated epitaxial growth steps, limiting their practical applications. Here we report van der Waals heterostructures based on a monolayer WSe2 and an Fe3GeTe2/hexagonal boron nitride ferromagnetic tunnelling contact that under a bias voltage can effectively inject spin-polarized holes into WSe2, leading to a population imbalance between ±K valleys, as confirmed by density functional theory calculations and helicity-dependent electroluminescence measurements. Under an external magnetic field, we observe that the helicity of electroluminescence flips its sign and exhibits a hysteresis loop in agreement with the magnetic hysteresis loop obtained from reflective magnetic circular dichroism characterizations on Fe3GeTe2. Our results could address key challenges of valleytronics and prove promising for van der Waals magnets for magneto-optoelectronics applications.

7.
ACS Appl Mater Interfaces ; 14(21): 24856-24863, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35476925

RESUMO

Extending the operation wavelength of silicon photonics to the mid-infrared (mid-IR) band will significantly benefit critical application areas, including health care, astronomy, and chemical sensing. However, a major hurdle for mid-IR silicon photonics has been the lack of high-speed, high-responsivity, and low noise-equivalent power (NEP) photodetectors. Here, we demonstrate a van der Waals (vdW) heterostructure mid-IR photodetector integrated on a silicon-on-insulator (SOI) waveguide. The detector is composed of vertically stacked black phosphorus (BP)/molybdenum ditelluride (MoTe2). We measured high responsivity (up to 0.85 A/W) over a 3-4 µm spectral range, indicating that waveguide-confined light could strongly interact with vdW heterostructures on top. In addition, the waveguide-integrated detector could be modulated at high speed (>10 MHz) and its switching performance shows excellent stability. These results, together with the noise analysis, indicate that the NEP of the detector is as low as 8.2 pW/Hz1/2. This reported critical missing piece in the silicon photonic toolbox will enable the wide-spread adoption of mid-IR integrated photonic circuits.

8.
Neuropathology ; 41(5): 371-375, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34374134

RESUMO

Calcifying pseudoneoplasms of the neuraxis (CAPNON) are rare, slow-growing, benign lesions occurring throughout the neuroaxis that are frequently misdiagnosed and overlooked by clinicians. Here, we report a case of a 56-year-old woman who presented with a history of recurrent headache for the previous six years. Magnetic resonance imaging (MRI) revealed a 2.3-cm-sized solid mass in the right frontal lobe that was surrounded by marked edematous areas. The lesion demonstrated dense calcification and avid enhancement. The lesion was initially diagnosed as oligodendroglioma, and then found to be CAPNON based on histopathology of a surgically resected tissue. Genetic analysis revealed a nonsense mutation in the CUL4B gene. The patient's condition appeared to reflect a reactive, rather than neoplastic, process. Clinicians should be prepared to detect such pseudotumors histopathologically in order to avoid unnecessary differential tests of neoplastic or infectious diseases, as well as potentially harmful therapies.


Assuntos
Calcinose , Oligodendroglioma , Sistema Nervoso Central , Proteínas Culina , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade
9.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 43(2): 211-215, 2021 Apr 28.
Artigo em Chinês | MEDLINE | ID: mdl-33966700

RESUMO

Objective To evaluate the efficacy and risks of autologous blood patch pleurodesis in patients with persistent air leak(PAL)after lung resection. Methods A total of 97 patients with PAL after lung resection in Beijing Shijitan Hospital from October 2014 to October 2019 were retrospectively reviewed,including 53 treated by autologous blood patch pleurodesis and 44 by the conventional way.The therapeutic effect,adverse reactions and complications were analyzed. Results All the patients with PAL were cured with autologous blood patch pleurodesis.Most air leaks(81.1%)ceased within 48 hours after treatment,and the left 18.9% patients got cured after a repeat.The mean tube retention time and the mean in-hospital stay were 8.4 days and 10.0 days in the autologous blood patch pleurodesis group and 13.5 days and 15.3 days in the conventional treatment group.A prolonged drainage time(P=0.00)and in-hospital stay(P=0.00)were observed in the conventional treatment group.No severe complications were observed except two patients developed slight fever and cutaneous emphysema. Conclusion In our experience,the autologous blood patch pleurodesis is an effective way with low risk of adverse reactions in the treatment of PAL.


Assuntos
Drenagem , Pleurodese , Humanos , Tempo de Internação , Pulmão , Estudos Retrospectivos
10.
Genome Biol ; 21(1): 195, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32762776

RESUMO

BACKGROUND: RNA-binding proteins (RBPs) function as master regulators of gene expression. Alterations in RBP expression and function are often observed in cancer and influence critical pathways implicated in tumor initiation and growth. Identification and characterization of oncogenic RBPs and their regulatory networks provide new opportunities for targeted therapy. RESULTS: We identify the RNA-binding protein SERBP1 as a novel regulator of glioblastoma (GBM) development. High SERBP1 expression is prevalent in GBMs and correlates with poor patient survival and poor response to chemo- and radiotherapy. SERBP1 knockdown causes delay in tumor growth and impacts cancer-relevant phenotypes in GBM and glioma stem cell lines. RNAcompete identifies a GC-rich region as SERBP1-binding motif; subsequent genomic and functional analyses establish SERBP1 regulation role in metabolic routes preferentially used by cancer cells. An important consequence of these functions is SERBP1 impact on methionine production. SERBP1 knockdown decreases methionine levels causing a subsequent reduction in histone methylation as shown for H3K27me3 and upregulation of genes associated with neurogenesis, neuronal differentiation, and function. Further analysis demonstrates that several of these genes are downregulated in GBM, potentially through epigenetic silencing as indicated by the presence of H3K27me3 sites. CONCLUSIONS: SERBP1 is the first example of an RNA-binding protein functioning as a central regulator of cancer metabolism and indirect modulator of epigenetic regulation in GBM. By bridging these two processes, SERBP1 enhances glioma stem cell phenotypes and contributes to GBM poorly differentiated state.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Neoplasias Encefálicas/etiologia , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Epigênese Genética , Feminino , Glioblastoma/etiologia , Glioblastoma/mortalidade , Glioblastoma/terapia , Humanos , Masculino , Camundongos , Neurogênese , Fenótipo , Prognóstico , Estados Unidos/epidemiologia
11.
Nano Lett ; 20(9): 6824-6830, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32816495

RESUMO

Light-emitting diodes (LEDs) based on III-V/II-VI materials have delivered a compelling performance in the mid-infrared (mid-IR) region, which enabled wide-ranging applications in sensing, including environmental monitoring, defense, and medical diagnostics. Continued efforts are underway to realize on-chip sensors via heterogeneous integration of mid-IR emitters on a silicon photonic chip, but the uptake of such an approach is limited by the high costs and interfacial strains, associated with the processes of heterogeneous integrations. Here, the black phosphorus (BP)-based van der Waals (vdW) heterostructures are exploited as room-temperature LEDs. The demonstrated devices emit linearly polarized light, and the spectra cover the technologically important mid-IR atmospheric window. Additionally, the BP LEDs exhibit fast modulation speed and exceptional operation stability. The measured peak extrinsic quantum efficiency is comparable to the III-V/II-VI mid-IR LEDs. By leveraging the integrability of vdW heterostructures, we further demonstrate a silicon photonic waveguide-integrated BP LED.

12.
Med Sci Monit ; 26: e919029, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32023237

RESUMO

BACKGROUND Cardiovascular complications, such as diabetic cardiomyopathy (DCM), are the leading cause of death in diabetic patients. Shengmai Powder (SMP) was found to have cardioprotective effects. MATERIAL AND METHODS Based on the systematic pharmacological methodology, this research determined the genes of DCM and the known targets of SMP, predicted potential compounds and targets of SMP, constructed networks for DCM and SMP, and performed network analysis. RESULTS Five network were constructed: (1) the DCM gene PPI network; (2) the Compound-compound target network of SMP; (3) the SMP-DCM PPI network; (4) the Compound-known target network of SMP; (5) and the SMP known target-DCM PPI network. Several DCM and treatment related targets, clusters, signaling pathways, and biological processes were found. CONCLUSIONS SMP is able to regulate glycometabolism-related, lipid metabolism-related, inflammatory response-related, oxidative stress-related signaling pathways, and biological processes and targets, which suggests that SMP may have a therapeutic effect on DCM.


Assuntos
Cardiotônicos/uso terapêutico , Cardiomiopatias Diabéticas/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Redes Reguladoras de Genes , Cardiotônicos/farmacologia , Análise por Conglomerados , Cardiomiopatias Diabéticas/genética , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Pós
13.
ACS Appl Mater Interfaces ; 12(1): 1201-1209, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31804794

RESUMO

Black phosphorus (BP), a narrow band gap semiconductor without out-of-plane dangling bonds, has shown promise for broadband and integrable photodetector applications. Simultaneously exhibiting high speed and high-efficiency operation, however, remains a critical challenge for current BP-based photodetectors. Here, we demonstrate a photodetector based on the BP-based van der Waals heterostructures. The developed photodetector enables broadband responses in the visible to mid-infrared range with external quantum efficiency ranging from 20 to 52% at room temperature. These results together with noise measurements indicate that the photodetector can detect light in the picowatt range. Furthermore, the demonstrated BP detector has ultrafast rise (1.8 ns) and fall (1.68 ns) times, and its photoresponse exhibits reproducible switching behavior even under consecutive and rapid light intensity modulations (2100 cycles, 200 MHz), as indicated by the eye-diagram measurement. By leveraging these features, we show our BP heterostructures can be configured as a point-like detector in a scanning confocal microscopy, useful for mid-infrared imaging applications.

14.
Oncol Rep ; 37(5): 2865-2874, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28339043

RESUMO

Novel molecular markers are required for defining subsets of diffuse astrocytic tumor patients with differing prognoses. Here, we examined ATP2A2 expression in 109 human diffuse astrocytic tumor samples (39 grade II diffuse astrocytoma (DA), 19 grade III anaplastic astrocytoma (AA), 51 grade IV glioblastoma) and its correlation with patient clinicopathologic characteristics. ATP2A2 expression significantly correlated with tumor grade and survival (P<0.05). High ATP2A2 expression was detected in 35.3% (18/51) of glioblastoma patients, compared to 61.5% (24/39) in grade II, and 52.6% (10/19) in grade III astrocytoma patients (P=0.043). The median survival was 45±5.3 (95% CI, 34.7-55.3) months in patients with high ATP2A2 expression and 16±5.0 (95% CI, 6.3-25.7) months in patients with low ATP2A2 expression (P<0.0001). Additionally, high grade astrocytoma patients with high ATP2A2 expression showed longer survival (median, 31.0±4.9 months, 95% CI, 21.4-40.7) than those with low ATP2A2 expression (median: 13.0±1.6 months, 95% CI, 9.9-16.1; P=0.027). Furthermore, both ATP2A2 overexpression and IDH1 mutation were detected in secondary glioblastoma, AA developed from DA and oligodendrogiomas with IDH1 mutation. The MTT assays showed that lentiviral ATP2A2 overexpression significantly suppressed the clonogenic growth of glioblastoma U251MG cells (P<0.05). Xenografts stably overexpressing ATP2A2 were markedly smaller in size 4 weeks post inoculation (P<0.05). Our findings identified high ATP2A2 expression in a subset of astrocytoma patients that was associated with better prognosis and ATP2A2 suppressed astrocytoma growth.


Assuntos
Astrocitoma/metabolismo , Astrocitoma/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Adolescente , Adulto , Idoso , Animais , Astrocitoma/genética , Neoplasias Encefálicas/genética , Linhagem Celular , Criança , Feminino , Humanos , Isocitrato Desidrogenase/genética , Masculino , Camundongos , Pessoa de Meia-Idade , Mutação , Gradação de Tumores , Transplante de Neoplasias , Prognóstico , Análise de Sobrevida , Regulação para Cima , Adulto Jovem
15.
Oncol Lett ; 12(5): 4054-4060, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27895771

RESUMO

Hepatocytic stem cells (HSCs) have inhibitory effects on hepatocarcinoma cells. The present study investigated the effects of HSC activity in hepatocarcinoma cells in vitro. A Transwell co-culture system of hepatocytic precursor (stem-like) WB-F344 cells and hepatoma CBRH-7919 cells was used to assess HSC activity in metastasized hepatoma cells in vitro. Nude mouse xenografts were used to assess HSC activity in vivo. Co-culture of hepatoma CBRH-7919 cells with WB-F344 cells suppressed the growth and colony formation, tumor cell migration and invasion capacity of CBRH-7919 cells. The nude mouse xenograft assay demonstrated that the xenograft size of CBRH-7919 cells following co-culture with WB-F344 cells was significantly smaller compared with that of control cells. Furthermore, the expression levels of the epithelial markers E-cadherin and ß-catenin were downregulated, while the mesenchymal markers α-SMA and vimentin were upregulated. Co-culture of CBRH-7919 cells with WB-F344 cells downregulated NF-κB and phospho-Akt expression. In conclusion, hepatocytic precursor (stem-like) WB-F344 cells inhibited the growth, colony formation and invasion capacity of metastasized hepatoma CBRH-7919 cells in vitro and in vivo by downregulating Akt/NF-κB signaling.

16.
J Chromatogr A ; 1432: 132-9, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26780846

RESUMO

An analytical method based on ultra-high performance supercritical fluid chromatography (UHPSFC) with photo-diode array detection (PDA) has been developed to quantify 15 sulfonamides and their N4-acetylation metabolites in serum. Under the optimized gradient elution conditions, it took only 7min to separate all 15 sulfonamides and the critical pairs of each parent drug and metabolite were completely separated. Variables affecting the UHPSFC were optimized to get a better separation. The performance of the developed method was evaluated. The UHPSFC method allowed the baseline separation and determination of 15 sulfonamides and metabolites with limit of detection ranging from 0.15 to 0.35µg/mL. Recoveries between 90.1 and 102.2% were obtained with satisfactory precision since relative standard deviations were always below 3%. The proposed method is simple, accurate, time-saving and green, it is applicable to a variety of sulfonamides detection in serum samples.


Assuntos
Sulfonamidas/sangue , Cromatografia com Fluido Supercrítico/métodos , Humanos , Sulfanilamidas/sangue
17.
Neurosciences (Riyadh) ; 20(3): 280-4, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26166599

RESUMO

The combination of vascular anomalies with gliomas is rarely seen in the CNS, and is defined as "angioglioma". However, the definition, category, and histopathogenesis of angiogliomas remain controversial. Here, we present an unusual case of spinal hemangioblastoma (HB) combined with pilocytic astrocytoma (PA). Spinal MRI revealed lesions extending from T9 to T12 segments, in a "sandwich-like" fashion. After resection of the tumor, histopathologic study confirmed the diagnosis of HB as well as PA. A comprehensive review of the literature was further conducted. We describe a case of spinal HB combined with PA, in addition we discuss the clinicopathological relationship between HB and PA under these conditions, which may facilitate the understanding of the histogenesis of an angioglioma and guide its diagnosis and treatment.


Assuntos
Astrocitoma/diagnóstico , Hemangioblastoma/diagnóstico , Neoplasias da Coluna Vertebral/diagnóstico , Astrocitoma/cirurgia , Hemangioblastoma/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias da Coluna Vertebral/cirurgia
18.
Int J Oncol ; 46(4): 1601-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25626081

RESUMO

miR-27a and BTG2 are implicated in gliomagenesis and glioma progression. However, hitherto, a link between miR-27a and BTG2 in glioma has not been reported. In the present study, we investigated the effects of miR-27a on the proliferation and invasiveness of glioblastoma cells in vitro and in a mouse xenograft model and further studied the relation between miR­27a expression and its target gene BTG2, which was identified by computation prediction algorithms. Our MTT and clonogenic assays showed that miR-27a overexpression significantly increased the clonogenic growth of glioblastoma U87MG and U251MG cells. The Transwell assays further revealed that miR-27a overexpression markedly increased the number of migrated U87MG and U251MG cells. TargetScan and other prediction algorithms identified BTG2 as a target gene of miR-27a, which was confirmed by EGFP reporter and immunoblotting assays showing an inverse relation between miR-27a expression and endogenous BTG2 expression. BTG2 overexpression also increased the proliferation and invasiveness of glioblastoma cells and BTG2 functioned downstream of miR-27a in modulating the proliferation and migration of glioblastoma cells. In conclusion, miR-27a modulates human glioblastoma growth and invasion by targeting BTG2.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Glioblastoma/genética , Glioblastoma/patologia , Proteínas Imediatamente Precoces/genética , MicroRNAs/genética , Proteínas Supressoras de Tumor/genética , Animais , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Biologia Computacional/métodos , Feminino , Glioblastoma/metabolismo , Humanos , Proteínas Imediatamente Precoces/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Invasividade Neoplásica , Transplante de Neoplasias , Proteínas Supressoras de Tumor/metabolismo
19.
Biochem Biophys Res Commun ; 446(4): 1261-7, 2014 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-24690174

RESUMO

Previous studies from this laboratory indicated that microRNA-21 (miR-21) contributes to chemoresistance of glioblastoma multiforme (GBM) cells to teniposide, a type II topoisomerase inhibitor. We also showed that LRRFIP1 is a target of miR-21. In this study, we found that higher baseline LRRFIP1 expression in human GBM tissue (n=60) is associated with better prognosis upon later treatment with teniposide. Experiments in cultured U373MG cells showed enhanced toxicity of teniposide against U373MG cells transfected with a vector that resulted in LRRFIP1 overexpression (vs. cells transfected with control vector). Experiments in nude mice demonstrated better response of LRRFIP1 overexpressing xenografts to teniposide. These findings indicate that high baseline LRRFIP1 expression in GBM is associated with better response to teniposide, and encourage exploring LRRFIP1 as a target for GBM treatment.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Proteínas de Ligação a RNA/genética , Teniposídeo/uso terapêutico , Inibidores da Topoisomerase II/uso terapêutico , Regulação para Cima , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Glioblastoma/diagnóstico , Glioblastoma/genética , Humanos , Camundongos , Camundongos Nus , MicroRNAs/genética , Prognóstico , Transfecção
20.
Biomed Environ Sci ; 26(6): 445-52, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23816578

RESUMO

OBJECTIVE: To investigate the impact of sub-chronic Aluminium-maltolate [Al(mal)3] exposure on the catabolism of amyloid precursor protein (APP) in rats. METHODS: Forty adult male Sprague-Dawley (SD) rats were randomly divided into five groups: the control group, the maltolate group (7.56 mg/kg BW), and the Al(mal)3 groups (0.27, 0.54, and 1.08 mg/kg BW, respectively). Control rats were administered with 0.9% normal saline through intraperitoneal (i.p.) injection. Maltolate and Al(mal)3 were administered to the rats also through i.p. injections. Administration was conducted daily for two months. Rat neural behavior was examined using open field tests (OFT). And the protein expressions and their mRNAs transcription related with APP catabolism were studied using enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (RT-PCR). RESULTS: The expressions of APP, ß-site APP cleaving enzyme 1 (BACE1) and presenilin-1 (PS1) proteins and their mRNAs transcription increased gradually with the increase of Al(mal)3 doses (P<0.05). The enzyme activity of BACE1 in the 0.54 and 1.08 mg/kg Al(mal)3 groups increased significantly (P<0.05). The expression of ß-amyloid protein (Aß) 1-40 gradually decreased while the protein expression of Aß1-42 increased gradually with the increase of Al(mal)3 doses (P<0.05). CONCLUSION: Result from our study suggested that one of the possible mechanisms that Al(mal)3 can cause neurotoxicity is that Al(mal)3 can increase the generation of Aß1-42 by facilitating the expressions of APP, ß-, and γ-secretase.


Assuntos
Proteínas Amiloidogênicas/metabolismo , Compostos Organometálicos/toxicidade , Pironas/toxicidade , Proteínas Amiloidogênicas/genética , Animais , Esquema de Medicação , Poluentes Ambientais/administração & dosagem , Poluentes Ambientais/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Compostos Organometálicos/administração & dosagem , Pironas/administração & dosagem , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
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