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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.
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Genes cdc , Glioblastoma , Humanos , Splicing de RNA , Divisão Celular , Núcleo Celular/metabolismo , Glioblastoma/metabolismo , Proteínas Nucleares/metabolismoRESUMO
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.
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Antioxidantes , Germinação , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/farmacologia , Sementes , Zea mays , Oxigênio/farmacologia , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/metabolismoRESUMO
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.
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Calcinose , Oligodendroglioma , Sistema Nervoso Central , Proteínas Culina , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-IdadeRESUMO
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.
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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.
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Drenagem , Pleurodese , Humanos , Tempo de Internação , Pulmão , Estudos RetrospectivosRESUMO
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.
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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 , PósRESUMO
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.
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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/cirurgiaRESUMO
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.
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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 , TransfecçãoRESUMO
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.
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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-DawleyRESUMO
OBJECTIVE: To set up a prediction rule for the pro-operative differential diagnosis of thyroid nodules and evaluate its clinical value. METHODS: All patients of thyroid nodules underwent thyroid operations in Changzheng hospital from June, 1997 to July, 2012 were included in this study. They were randomly divided into the derivation cohort (2/3) and the validation cohort (1/3). A prediction rule was developed based on the logistic regression model and the scoring system was established in accordance with assigning of the value of each variable ß in the model. The prediction consistency, discriminatory power and diagnostic accuracy were conducted to evaluate the clinical value of the scoring system. RESULTS: A total of 13 980 patients were enrolled in the study with 9195 in the derivation cohort and 4785 in the validation cohort. The prediction rule consisted of 18 variables, which were gender, clinical manifestations including fever, neck sore, neck mass, palpitation and sweating, serum level of thyroid stimulating hormone (TSH) , free triiodothyronine (FT3) , thyroid peroxidase antibody (TPOAb) , thyroglobulin antibody (TgAb) , thyroglobulin (Tg) , calcitonin and carcinoembryonic antigen (CEA) , ultrasonography features including nodules number, location, size, boundaries and ethological patterns and the presence and patterns of lymph nodes. The model showed good calibration consistency (P = 0.437) and discrimination power (area under the receiver operating characteristic curve was 0.928) in the derivation cohort. The sensitivity, specificity, accuracy, positive predictive value, negative predictive value, positive likelihood ratio and negative likelihood ratio of the model were 89.3%, 81.5%, 83.2%, 56.8%, 96.6%, 4.83 and 0.13, respectively. CONCLUSION: The prediction rule and its scoring system established in the study are efficacious for the calibration and discrimination of thyroid nodules in Chinese population, which could be a useful tool for the pro-operative risk stratification.
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Nódulo da Glândula Tireoide/diagnóstico , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
OBJECTIVE: To study whether the effects of Leflunomide were different in treating patients with rheumatoid arthritis (RA) of different Chinese medical syndrome patterns. METHODS: Totally 150 RA patients were recruited and assigned to 5 Chinese medical syndrome types, i.e., the heat-dampness blocking collateral type, cold-dampness blocking collateral type, Shen-qi deficiency cold type, Gan-Shen yin deficiency type, and stagnant blood blocking collateral type according to Chinese medical syndrome typing standards. They were treated with Leflunomide, 3 months as one therapeutic course. The parameters including numbers of joint tenderness and swelling, morning stiffness time, scores estimated by Visual Analog Scale (VAS), as well as laboratory indices involving rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), American College of Rheumatology 20% improvement (ACR20), and American College of Rheumatology 50% improvement (ACR50) were observed before and after treatment, and statistically analyzed. RESULTS: After treatment the numbers of joint tenderness, numbers of joint swelling, VAS scores, ESR, CRP, and RF all decreased, showing statistical difference when compared with those before treatment (P < 0.05). The morning stiffness time was shortened in the heat-dampness blocking collateral type, cold-dampness blocking collateral type, and stagnant blood blocking collateral type, showing statistical difference (P < 0.05). Of them, the numbers of joint tenderness, the numbers of joint swelling, the morning stiffness time, RF, VAS scores, and the improvement of the total effective rate were obviously better in the heat-dampness blocking collateral type, cold-dampness blocking collateral type, and stagnant blood blocking collateral type than in the Shen-qi deficiency cold type and Gan-Shen yin deficiency type, showing statistical difference (P < 0.05). CONCLUSIONS: Leflunomide showed significant effects in treating RA. Of them, its effects were obviously better in the heat-dampness blocking collateral type, cold-dampness blocking collateral type, and stagnant blood blocking collateral type than in the Shen-qi deficiency cold type and Gan-Shen yin deficiency type.
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Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Isoxazóis/uso terapêutico , Adolescente , Adulto , Idoso , Feminino , Humanos , Leflunomida , Masculino , Medicina Tradicional Chinesa , Pessoa de Meia-Idade , Deficiência da Energia Yin/tratamento farmacológico , Adulto JovemRESUMO
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.
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Deslocamento do Disco Intervertebral , Dor Lombar , Ortopedia , Feminino , Masculino , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Deslocamento do Disco Intervertebral/cirurgia , Impressão Tridimensional , TecnologiaRESUMO
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.
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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.
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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.
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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.
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ABCG2, which encodes an ATP-binding cassette transporter protein, is associated with the phenotype of cancer stem cells and is used to define the pluripotential side population cells by flow cytometry and slide-cytometry. MicroRNAs control a wide array of biological processes (e.g., cell differentiation, proliferation and apoptosis) whose dysregulation is a hallmark of cancer. MicroRNA-328 (miR-328) is underexpressed in many cancers including glioblastoma multiforme and contributes to tumor resistance to chemotherapy. ABCG2 is associated with multi-drug resistance and is also highly expressed in glioblastoma. Some preliminary studies have shown that ABCG2 is the target gene for miRNA-328. Thus, we hypothesize that modulating ABCG2 expression by targeting miRNA-328 in glioblastoma cancer stem cells could represent a promising strategy for therapeutic manipulation to increase the efficacy of chemotherapeutic agents for glioblastoma, a highly lethal type of cancer.
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Transportadores de Cassetes de Ligação de ATP/genética , Neoplasias Encefálicas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/genética , MicroRNAs/genética , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/biossíntese , Transportadores de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Neoplasias Encefálicas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Resistência a Múltiplos Medicamentos , Expressão Gênica , Glioblastoma/metabolismo , Humanos , MicroRNAs/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Células-Tronco Neoplásicas/patologiaRESUMO
In our screening program for new agrochemicals from Chinese medicinal herbs, Murraya exotica was found to possess insecticidal activity against the maize weevil, Sitophilus zeamais and red flour beetle, Tribolium castaneum. The essential oil of aerial parts of M. exotica was obtained by hydrodistillation and investigated by GC and GC-MS. The main components of M. exotica essential oil were spathulenol (17.7%), alpha-pinene (13.3%), caryophyllene oxide (8.6%), and alpha-caryophyllene (7.3%). Essential oil of M. exotica possessed fumigant toxicity against S. zeamais and T. castaneum adults with LC(50) values of 8.29 and 6.84 mg/L, respectively. The essential oils also show contact toxicity against S. zeamais and T. castaneum adults with LD(50) values of 11.41 and 20.94 microg/adult, respectively.
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Murraya/química , Óleos Voláteis/química , Óleos Voláteis/toxicidade , Componentes Aéreos da Planta/química , Tribolium/efeitos dos fármacos , Gorgulhos/efeitos dos fármacos , Animais , InseticidasRESUMO
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.
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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.