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1.
EMBO J ; 41(5): e108119, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35099830

RESUMO

Lysosomes function not only as degradatory compartments but also as dynamic intracellular calcium ion stores. The transient receptor potential mucolipin 1 (TRPML1) channel mediates lysosomal Ca2+ release, thereby participating in multiple cellular functions. The pentameric Ragulator complex, which plays a critical role in the activation of mTORC1, is also involved in lysosomal trafficking and is anchored to lysosomes through its LAMTOR1 subunit. Here, we report that the Ragulator restricts lysosomal trafficking in dendrites of hippocampal neurons via LAMTOR1-mediated tonic inhibition of TRPML1 activity, independently of mTORC1. LAMTOR1 directly interacts with TRPML1 through its N-terminal domain. Eliminating this inhibition in hippocampal neurons by LAMTOR1 deletion or by disrupting LAMTOR1-TRPML1 binding increases TRPML1-mediated Ca2+ release and facilitates dendritic lysosomal trafficking powered by dynein. LAMTOR1 deletion in the hippocampal CA1 region of adult mice results in alterations in synaptic plasticity, and in impaired object-recognition memory and contextual fear conditioning, due to TRPML1 activation. Mechanistically, changes in synaptic plasticity are associated with increased GluA1 dephosphorylation by calcineurin and lysosomal degradation. Thus, LAMTOR1-mediated inhibition of TRPML1 is critical for regulating dendritic lysosomal motility, synaptic plasticity, and learning.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Cálcio/metabolismo , Hipocampo/metabolismo , Lisossomos/metabolismo , Neurônios/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo , Animais , Linhagem Celular Tumoral , Células Cultivadas , Células HeLa , Humanos , Camundongos , Plasticidade Neuronal/fisiologia
2.
Int J Cancer ; 154(9): 1639-1651, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38212905

RESUMO

TRPS1 is aberrantly expressed in a variety of tumors, including breast, prostate, and gastric cancers, and is strongly associated with tumorigenesis or prognosis. However, the role of TRPS1 in high grade serous ovarian carcinoma (HGSC) is unknown. We investigated the relationship between TRPS1 expression and clinicopathology in HGSC patients. The tumor-related regulatory mechanisms of TRPS1 was explored through in vivo and vitro experiments. The results showed that TRPS1 was highly expressed in HGSC compared to normal tissues. It was also linked to the cell proliferation index Ki67 and poor prognosis. In vivo experiments showed that knockdown of TRPS1 could inhibit tumor growth. In vitro experiments, knockdown of TRPS1 inhibited the proliferation of ovarian cancer cells. TRPS1 exerted its regulatory role as a transcription factor, binding to the PSAT1 promoter and promoting the expression of PSAT1 gene. Meanwhile, PSAT1 was positively correlated with CCND1 expression. These results suggest that TRPS1 affects HGSC proliferation and cell cycle by regulating PSAT1 and thus CCND1 expression.


Assuntos
Cistadenocarcinoma Seroso , Neoplasias Ovarianas , Masculino , Feminino , Humanos , Cistadenocarcinoma Seroso/patologia , Neoplasias Ovarianas/patologia , Fatores de Transcrição/genética , Prognóstico , Proliferação de Células , Proteínas Repressoras/genética
3.
Opt Express ; 31(12): 19754-19765, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381384

RESUMO

We report a sub-terahertz scattering-type scanning near-field microscope (sub-THz s-SNOM) which uses a 6 mm long metallic tip driven by a quartz tuning fork as the near-field probe. Under continuous-wave illumination by a 94 GHz Gunn diode oscillator, terahertz near-field images are obtained by demodulating the scattered wave at both the fundamental and the second harmonic of the tuning fork oscillation frequency together with the atomic-force-microscope (AFM) image. The terahertz near-field image of a gold grating with a period of 2.3 µm obtained at the fundamental modulation frequency agrees well with the AFM image. The experimental relationship between the signal demodulated at the fundamental frequency and the tip-sample distance is well fitted with the coupled dipole model indicating that the scattered signal from the long probe is mainly contributed by the near-field interaction between the tip and the sample. This near-filed probe scheme using quartz tuning fork can adjust the tip length flexibly to match the wavelength over the entire terahertz frequency range and allows for operation in cryogenic environment.

4.
Opt Express ; 31(6): 10720-10731, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-37157613

RESUMO

To satisfy the demand for broadband and high-sensitivity terahertz detectors, we designed and verified a broadband terahertz detector built with antenna-coupled AlGaN/GaN high-electron-mobility transistors (HEMTs). Eighteen pairs of dipole antennas with different center frequency from 0.24 to 7.4 THz are arrayed into a bow-tie pattern. The corresponding eighteen transistors have common a source and a drain but different gated channels coupled by the corresponding antennas. The photocurrents generated by each gated channel are combined in the drain as the output port. With incoherent terahertz radiation from a hot blackbody in a Fourier-transform spectrometer (FTS), the detector exhibits a continuous response spectrum from 0.2 to 2.0 THz at 298 K and from 0.2 to 4.0 THz at 77 K, respectively. The results agree well with simulations taking into account the silicon lens, antenna and blackbody radiation law. The sensitivity is characterized under coherent terahertz irradiation, the average noise-equivalent power (NEP) is about 188 p W/H z at 298 K and 19 p W/H z at 77 K from 0.2 to 1.1 THz, respectively. A maximum optical responsivity of 0.56 A/W and a minimum NEP of 7.0 p W/H z at 0.74 THz are achieved at 77 K. The blackbody response spectrum is divided by the blackbody radiation intensity to obtain a performance spectrum, which is calibrated by measuring coherence performance from 0.2 to 1.1 THz to evaluate detector performance at frequencies above 1.1 THz. At 298 K, the NEP is about 1.7 n W/H z at 2.0 THz. At 77 K, the NEP is about 3 n W/H z at 4.0 THz. For further improvements in sensitivity and bandwidth, high-bandwidth coupling components, smaller series resistance, smaller gate lengths and high-mobility materials need to be considered.

5.
Cell Biol Toxicol ; 39(6): 3141-3157, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37531013

RESUMO

Infertility has attracted global concern, and disruption of testosterone is a common cause of male infertility. Exploring the critical factors in testosterone biosynthesis may provide new insights for disease research and clinical therapy. Research on trichorhinophalangeal syndrome-1 (Trps1) gene has recently been focus on cancers; it is yet unknown whether Trps1 produces a marked effect in the male reproductive system. In the current study, single-cell RNA sequencing analysis of trichorhinophalangeal syndrome-1 gene (Trps1) expression in mouse testes and cleavage under targets and tagmentation and RNA sequencing were utilized to investigate the functionality of Trps1 in mouse Leydig cells. Knockdown of Trps1 increased testosterone synthesis in vitro and vivo using adeno-associated viral delivery and conditional knockout models. The results showed that Trps1 was abundantly expressed in Leydig cells. The expression levels of both steroidogenic factor-1 (Sf-1) and steroidogenic enzymes (Cyp11a1, Hsd3b, Cyp17a1, and Hsd17b3) as well as testosterone secretion were increased after Trps1 deficiency in vivo and vitro. Furthermore, disruption of Trps1 reduced histone deacetylase 1/2 activity and increased histone H3 acetylation in the Sf-1 promoter, thereby promoting testosterone secretion. Interestingly, Sf-1 also regulated the transcription of Trps1 through activating transcription factor 2. These results indicate that Trps1 targets Sf-1 to affect steroidogenesis through histone acetylation and shed light on the critical role of Trps1 functioning in the mouse Leydig cells.


Assuntos
Células Intersticiais do Testículo , Testosterona , Camundongos , Animais , Masculino , Células Intersticiais do Testículo/metabolismo , Sequência de Bases , Regiões Promotoras Genéticas , Proteínas Repressoras/genética
6.
Cancer Sci ; 113(4): 1277-1291, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35080085

RESUMO

Long noncoding RNAs (lncRNAs) have been found to play an important role in the occurrence and development of endometrial carcinoma (EC). Here, using RNA sequencing analysis, we systemically screened and identified the lncRNA eukaryotic translation initiation factor 1A, X-linked (EIF1AX)-AS1, which is aberrantly downregulated in clinical EC tissues and closely correlated with tumor type. EIF1AX-AS1 markedly inhibited EC cell proliferation and promoted apoptosis in vitro and in vivo. Mechanistically, EIF1AX-AS1 interacts with EIF1AX mRNA and poly C binding protein 1 (PCBP1), which promote EIF1AX mRNA degradation. Intriguingly, by interacting with internal ribosome entry site-related protein Y-box binding protein 1 (YBX-1), EIF1AX promotes c-Myc translation through the internal ribosome entry site pathway. c-Myc promotes EIF1AX transcription and thus forms a feed-forward loop to regulate EC cell proliferation. Taken together, these data reveal new insights into the biology driving EC proliferation and highlights the potential of lncRNAs as biomarkers for prognosis and future therapeutic targets for cancer.


Assuntos
Neoplasias do Endométrio , RNA Longo não Codificante , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias do Endométrio/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Sítios Internos de Entrada Ribossomal , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Opt Express ; 30(24): 42956-42966, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36523005

RESUMO

The foundation for polarization-based terahertz applications is the acquisition of polarization information. To develop an all-electronic terahertz straightforward polarization detection system, in this paper, a terahertz polarization detector based on three antenna-coupled AlGaN/GaN high-electron-mobility transistors (HEMTs) on a single chip is designed and fabricated. The function of the direct polarization detector is proven by measuring the polarization angle of linearly polarized continuous-wave terahertz radiation at 216 GHz. The average deviation and maximum deviation of the measured polarization angle are 3.7 degrees and 10 degrees, respectively. The error comes mainly from the disturbance of the local terahertz field by the interference effect. Simulations locate the sources of interference and guide the further device design and packaging of such kind of direct polarization detectors.

8.
Toxicol Appl Pharmacol ; 441: 115969, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35259346

RESUMO

Icariin (ICA), extracted from Epimedium, is a flavonoid used in traditional Chinese medicine. Di(2-ethylhexyl) phthalate (DEHP) is a phthalate used in commercial products as a plasticizer that can influence the human endocrine and reproduction system. We previously found that ICA reversed DEHP-induced damage through the prevention of reactive oxygen species accumulation and promotion of testosterone secretion. Here we investigated the mechanisms of ICA in promoting testosterone secretion from murine Leydig cells. We used ICA, DEHP, the Akt agonist SC-79, the Akt inhibitor MK2206, and the Creb inhibitor KG501 to determine the effect of these treatments on the expression levels of the steroidogenic enzymes, Cyp11a1 and Hsd3b, which play critical roles in androgen production, in Leydig cells. Bioinformatic analysis was used to search for ICA-targeted proteins and their associated pathways. We found that icariin interacted with estrogen receptor on the cell membrane, leading to increased phosphorylation levels of Akt and Creb proteins and enhanced transcription of genes encoding steroidogenic enzymes and testosterone synthesis. We further investigated ICA activity in vivo using male mice pretreated with 100 mg/kg ICA and then treated with 750 mg/kg DEHP. ICA pretreatment reversed the reduced protein expression levels of Cyp11a1 and Hsd3b induced by DEHP in Leydig cells in vivo. Furthermore, while the phosphorylation levels of Akt and Creb were decreased in testes of mice exposed to DEHP alone, these effects were reversed by ICA pretreatment. These findings indicate that ICA promotes testosterone synthesis via the Esr1/Src/Akt/Creb/Sf-1 signaling pathway.


Assuntos
Dietilexilftalato , Células Intersticiais do Testículo , Animais , Enzima de Clivagem da Cadeia Lateral do Colesterol , Dietilexilftalato/farmacologia , Flavonoides , Masculino , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Testículo , Testosterona/metabolismo
9.
Biotechnol Appl Biochem ; 69(1): 364-375, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33533517

RESUMO

d-Psicose 3-epimerase (DPEase) can catalyze the isomerization of d-fructose to be rare sugar d-psicose, which has wide application prospects in the food and medical fields. In this study, the DPEase gene from Agrobacterium tumefaciens was constructed into plasmid pMA5, and was successfully expressed in the host Bacillus subtilis WB600 (B. subtilis). After optimization of the fermentation conditions, whole recombinant B. subtilis WB600/pMA5-At-DEPase(O) cells produced d-psicose from d-fructose with a conversion rate of 29.01 ± 0.19%, which could be used for the efficient synthesis of d-psicose. To further improve the whole recombinant B. subtilis application, B. subtilis cells were immobilized onto a gel bead biocatalyst by Ca-alginate. After optimization of the biotransformation conditions, the conversion rate of the immobilized biocatalyst reached 20.74 ± 0.39%, which was lower than the free cells. However, the results showed that the immobilized biocatalyst had higher thermal/pH stability and storability, and the gel beads could be recycled for at least six batches. The results showed that the amount of d-psicose generated reached 32.83 ± 2.56 g/L with the immobilized biocatalyst after six times biotransformation, whereas the free cells produced only approximately 10.44 ± 0.07 g/L. The results showed that immobilized recombinant B. subtilis cells are promising to use for the efficient synthesis of d-psicose.


Assuntos
Agrobacterium tumefaciens , Bacillus subtilis , Agrobacterium tumefaciens/genética , Bacillus subtilis/genética , Carboidratos Epimerases/genética , Frutose , Concentração de Íons de Hidrogênio , Racemases e Epimerases , Temperatura
10.
Neural Plast ; 2022: 3923384, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36237484

RESUMO

Angelman syndrome (AS) is a rare neurodevelopmental disorder characterized by severe developmental delay, motor impairment, language and cognition deficits, and often with increased seizure activity. AS is caused by deficiency of UBE3A, which is both an E3 ligase and a cofactor for transcriptional regulation. We previously showed that the small conductance potassium channel protein SK2 is a UBE3A substrate, and that increased synaptic SK2 levels contribute to impairments in synaptic plasticity and fear-conditioning memory, as inhibition of SK2 channels significantly improved both synaptic plasticity and fear memory in male AS mice. In the present study, we investigated UBE3a-mediated regulation of synaptic plasticity and fear-conditioning in female AS mice. Results from both western blot and immunofluorescence analyses showed that synaptic SK2 levels were significantly increased in hippocampus of female AS mice, as compared to wild-type (WT) littermates. Like in male AS mice, long-term potentiation (LTP) was significantly reduced while long-term depression (LTD) was enhanced at hippocampal CA3-CA1 synapses of female AS mice, as compared to female WT mice. Both alterations were significantly reduced by treatment with the SK2 inhibitor, apamin. The shunting effect of SK2 channels on NMDA receptor was significantly larger in female AS mice as compared to female WT mice. Female AS mice also showed impairment in both contextual and tone memory recall, and this impairment was significantly reduced by apamin treatment. Our results indicate that like male AS mice, female AS mice showed significant impairment in both synaptic plasticity and fear-conditioning memory due to increased levels of synaptic SK2 channels. Any therapeutic strategy to reduce SK2-mediated inhibition of NMDAR should be beneficial to both male and female patients.


Assuntos
Síndrome de Angelman , Síndrome de Angelman/metabolismo , Animais , Apamina , Modelos Animais de Doenças , Feminino , Hipocampo/metabolismo , Potenciação de Longa Duração/fisiologia , Masculino , Transtornos da Memória/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Plasticidade Neuronal/fisiologia , Receptores de N-Metil-D-Aspartato/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Baixa , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/farmacologia
11.
J Neurovirol ; 26(1): 84-94, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31512144

RESUMO

Enterovirus A71 (EV-A71) is the major cause of severe hand-foot-and-mouth diseases (HFMD), especially encephalitis and other nervous system diseases. EV-A71 capsid protein VP1 mediates virus attachment and is the important virulence factor in the EV-A71pathogenesis. In this study, we explored the roles of VP1 in the permeability of blood-brain barrier (BBB). Sera albumin, Evans blue, and dextran leaked into brain parenchyma of the 1-week-old C57BL/6J mice intracranially injected with VP1 recombinant protein. VP1 also increased the permeability of the brain endothelial cells monolayer, an in vitro BBB model. Tight junction protein claudin-5 was reduced in the brain tissues or brain endothelial cells treated with VP1. In contrast, VP1 increased the expression of virus receptor vimentin, which could be blocked with VP1 neutralization antibody. Vimentin expression in the VP1-treated brain endothelial cells was regulated by TGF-ß/Smad-3 and NF-κB signal pathways. Moreover, vimentin over-expression was accompanied with compromised BBB. From these studies, we conclude that EV-A71 virus capsid protein VP1 disrupted BBB and increased virus receptor vimentin, which both may contribute to the virus entrance into brain and EV-A71 CNS infection.


Assuntos
Barreira Hematoencefálica/virologia , Proteínas do Capsídeo/metabolismo , Infecções por Enterovirus/virologia , Enterovirus/patogenicidade , Vimentina/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Encéfalo/virologia , Permeabilidade Capilar/fisiologia , Células Endoteliais , Infecções por Enterovirus/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Virulência/metabolismo
12.
Opt Express ; 28(4): 4911-4920, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32121721

RESUMO

Aiming at the requirement of passive terahertz imaging, we report a high-sensitivity terahertz detector based on an antenna-coupled AlGaN/GaN high-electron-mobility transistor (HEMT) at 77 K without using low-noise terahertz amplifier. The measured optical noise-equivalent power and the noise-equivalent temperature difference of the detector were about 0.3p W/H z and 370 mK in a 200 ms integration time over a bandwidth of 0.7 - 0.9 THz, respectively. By using this detector, we demonstrated passive terahertz imaging of room-temperature objects with signal-to-noise ratio up to 13 dB. Further improvement in the sensitivity may allow passive terahertz imaging using AlGaN/GaN-HEMT at room temperature.

13.
Toxicol Appl Pharmacol ; 378: 114612, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31175881

RESUMO

Infertility caused by environmental pollution is becoming a global problem, but an effective prevention or treatment is lacking. Icariin (ICA) is a flavonoid used in traditional Chinese medicine. The present study investigated the possible roles of ICA in preventing testicular dysfunction caused by di(2-ethylhexyl) phthalate (DEHP), one of the most studied environmental endocrine disruptors. Cultured mouse Leydig cells were pretreated with ICA and exposed to DEHP to determine ICA effects upon cell proliferation, reactive oxygen species (ROS) levels, mitochondrial membrane potential (Δψm), testosterone levels and the expression of transcription factor SF-1 and steroidogenic enzymes (CYP11, 3ß-HSD and 17ß-HSD), which play critical roles in androgen production. Our results showed that ICA reversed the adverse effect of DEHP on Leydig cell proliferation, and decreased ROS levels and elevated Δψm levels. Also, ICA promoted testosterone production and up-regulated the expression of SF-1 and steroidogenic enzymes. We investigated ICA actions in vivo, using male mice administrated DEHP followed by ICA. Exposure to DEHP decreased epididymal sperm counts and disrupted seminiferous tubules, and both of these effects were reversed by ICA treatment. These results showed that the mechanisms of ICA in protecting mouse testes against DEHP-induced damage involves the prevention of ROS accumulation and promotion of testosterone secretion.


Assuntos
Dietilexilftalato/efeitos adversos , Flavonoides/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Ácidos Ftálicos/efeitos adversos , Substâncias Protetoras/farmacologia , Testosterona/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Disruptores Endócrinos/metabolismo , Feminino , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo
15.
BMC Public Health ; 19(1): 281, 2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30849990

RESUMO

BACKGROUND: Few studies in China have examined personal ultraviolet radiation (UVR) exposure using polysulfone dosimetry. METHODS: In this study, 93 mother and adolescent child pairs (N = 186) from two locations in China, one rural (higher latitude) and one urban (lower latitude), completed 3 days of personal UVR dosimetry and a sun/clothing diary, as part of a larger pilot study. RESULTS: The average daily ambient UVR in each location as measured by dosimetry was 20.24 Minimal Erythemal Doses (MED) in the rural location and 20.53 MED in the urban location. Rural mothers had more average daily time outdoors than urban mothers (5.5 h, compared with 1.5 h, in urban mothers) and a much higher daily average personal UVR exposure (4.50 MED, compared with 0.78 MED in urban mothers). Amongst adolescents, rural males had the highest average daily personal UVR exposure, followed by rural females, urban females and urban males (average 2.16, 1.05, 0.81, and 0.48 MED, respectively). CONCLUSIONS: Although based on small numbers, our findings show the importance of geographic location, age, work/school responsibilities, and sex of the adolescents in determining personal UVR exposure in China. These results suggest that latitude of residence may not be a good proxy for personal UVR exposure in all circumstances.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Exposição à Radiação/estatística & dados numéricos , Raios Ultravioleta , Adolescente , Criança , China , Estudos de Coortes , Feminino , Humanos , Masculino , Mães , Projetos Piloto , Radiometria , População Rural
16.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(5): 491-496, 2019 May.
Artigo em Zh | MEDLINE | ID: mdl-31104669

RESUMO

OBJECTIVE: To study the effect of 280 nm-LED ultraviolet irradiation on the proliferation of acute promyelocytic leukemia (APL) HL-60 cells under hypoxic conditions and related mechanism. METHODS: HL-60 cells in the logarithmic growth phase were selected and divided into control, hypoxia, ultraviolet and hypoxia+ultraviolet groups. The cells in the hypoxia group were treated with cobalt chloride (with a final concentration of 150 µmol/L), those in the ultraviolet group were irradiated by 280 nm-LED ultraviolet with an energy intensity of 30 J/m2, and those in the hypoxia+ultraviolet group were treated with cobalt chloride and then irradiated by 280 nm-LED ultraviolet. After 48 hours of treatment, the cells were placed under an invert microscope to observe cell morphology. CCK-8 assay was used to measure the inhibition rate of cell proliferation. Annexin V-FITC/PI double staining flow cytometry was used to evaluate cell apoptosis. Quantitative real-time PCR was used to measure the mRNA expression of Bcl-2. Each experiment above was repeated three times independently. RESULTS: Compared with the control group, the experimental groups showed shrinkage, decreased brightness, and disordered arrangement of cells, and the number of cells decreased over the time of culture. There were significant differences in the inhibition rate of cell proliferation and cell apoptosis rate among the groups (P<0.01), and the hypoxia+ultraviolet group showed the strongest inhibition of cell proliferation and induction of cell apoptosis, followed by the ultraviolet group and the hypoxia group. Compared with the control group, the other three groups had a gradual reduction in the mRNA expression of Bcl-2, and the hypoxia+ultraviolet group had a significantly greater reduction than the hypoxia and ultraviolet groups (P<0.01). CONCLUSIONS: Both hypoxia and ultraviolet irradiation can inhibit the proliferation of HL-60 cells and induce cell apoptosis, and ultraviolet irradiation has a better effect on proliferation inhibition and cell apoptosis under hypoxic conditions than under normoxic conditions, possibly by downregulating the mRNA expression of Bcl-2.


Assuntos
Leucemia Promielocítica Aguda , Apoptose , Hipóxia Celular , Proliferação de Células , Humanos
17.
Opt Express ; 26(24): 31794-31807, 2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30650759

RESUMO

Plasmon in two-dimensional electron gas (2DEG) has long been considered as a promising active medium for terahertz emitters and detectors. However, the efficiency of terahertz plasmonic devices is severely limited by the high damping rate of plasma wave in solid state. In addition to the enhancement of plasmon lifetime by using 2DEGs with higher carrier mobility, engineering on the boundary condition and electromagnetic environment of plasmon cavity helps to preserve the plasmon states. Here we report on terahertz reflection spectroscopy of plasmon states in a grating-coupled AlGaN/GaN-2DEG plasmonic device at 7 K in equilibrium with ambient blackbody irradiation. Localized plasmon states and plasmon-polariton states were observed when the core plasmonic device is integrated with a silicon lens and when it is embedded in a terahertz Fabry-Pérot cavity, respectively. Simulation results including the reflection spectra and total reflection power agree well with the measured results. The Rabi splitting is found to be inversely proportional to the resonance frequency, and follows a linear relation with the square root of the sheet electron density. A normalized coupling ratio, ΩRω0≈0.13, is achieved between the Rabi splitting ΩR and the resonance frequency ω0. The coupling ratio could be further increased to allow for ultrastrong coupling between terahertz photons and plasmons.

19.
BMC Cancer ; 17(1): 95, 2017 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-28152983

RESUMO

BACKGROUND: Australia and New Zealand have the highest incidence of colorectal cancer (CRC) in the world, presenting considerable health, economic, and societal burden. Over a third of the Australian population live in regional areas and research has shown they experience a range of health disadvantages that result in a higher disease burden and lower life expectancy. The extent to which geographical disparities exist in CRC management and outcomes has not been systematically explored. The present review aims to identify the nature of geographical disparities in CRC survival, clinical management, and psychosocial outcomes. METHODS: The review followed PRISMA guidelines and searches were undertaken using seven databases covering articles between 1 January 1990 and 20 April 2016 in an Australian setting. Inclusion criteria stipulated studies had to be peer-reviewed, in English, reporting data from Australia on CRC patients and relevant to one of fourteen questions examining geographical variations in a) survival outcomes, b) patient and cancer characteristics, c) diagnostic and treatment characteristics and d) psychosocial and quality of life outcomes. RESULTS: Thirty-eight quantitative, two qualitative, and three mixed-methods studies met review criteria. Twenty-seven studies were of high quality, sixteen studies were of moderate quality, and no studies were found to be low quality. Individuals with CRC living in regional, rural, and remote areas of Australia showed poorer survival and experienced less optimal clinical management. However, this effect is likely moderated by a range of other factors (e.g., SES, age, gender) and did appear to vary linearly with increasing distance from metropolitan centres. No studies examined differences in use of stoma, or support with stomas, by geographic location. CONCLUSIONS: Overall, despite evidence of disparity in CRC survival and clinical management across geographic locations, the evidence was limited and at times inconsistent. Further, access to treatment and services may not be the main driver of disparities, with individual patient characteristics and type of region also playing an important role. A better understanding of factors driving ongoing and significant geographical disparities in cancer related outcomes is required to inform the development of effective interventions to improve the health and welfare of regional Australians.


Assuntos
Neoplasias Colorretais/epidemiologia , Disparidades em Assistência à Saúde , Austrália/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pesquisa Qualitativa , Qualidade de Vida , População Rural , Análise de Sobrevida
20.
Cell Mol Life Sci ; 73(22): 4303-4314, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27173058

RESUMO

Emerging evidence is implicating abnormal activation of the mechanistic target of rapamycin (mTOR) pathway in several monogenetic neuropsychiatric disorders, including Angelman syndrome (AS), which is caused by deficiency in maternally inherited UBE3A. Using an AS mouse model, we show that semi-chronic rapamycin treatment improves long-term potentiation (LTP) and actin polymerization in hippocampal slices, spine morphology, and fear-conditioning learning. Activity of mTORC1 and of its downstream substrate, S6K1, was increased in hippocampus of AS mice. However, mTORC2 activity, as reflected by PKCα levels, was decreased. Both increased mTORC1 and decreased mTORC2 activities were reversed by semi-chronic rapamycin treatment. Acute treatment of hippocampal slices from AS mice with rapamycin or an S6K1 inhibitor, PF4708671, improved LTP, restored actin polymerization, and normalized mTORC1 and mTORC2 activity. These treatments also reduced Arc levels in AS mice. Treatment with Torin 1, an inhibitor of both mTORC1 and mTORC2, partially rescued LTP and actin polymerization in hippocampal slices from AS mice, while partially impairing them in wild-type (WT) mice. Torin 1 decreased mTORC1 and increased mTORC2 activity in slices from AS mice but inhibited both mTORC1 and mTORC2 in WT mice. Finally, an mTORC2 activator, A-443654, increased hippocampal LTP in AS mice and actin polymerization in both WT and AS mice. Collectively, these results indicate that events set in motion by increased mTORC1 and decreased mTORC2 activities, including increased Arc translation and impaired actin remodeling, are crucial in AS pathogenesis. Therefore, selectively targeting these two master kinase complexes may provide new therapeutic approaches for AS treatment.


Assuntos
Síndrome de Angelman/fisiopatologia , Hipocampo/fisiopatologia , Aprendizagem , Complexos Multiproteicos/antagonistas & inibidores , Complexos Multiproteicos/metabolismo , Plasticidade Neuronal , Proteínas Quinases S6 Ribossômicas 70-kDa/antagonistas & inibidores , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Actinas/metabolismo , Síndrome de Angelman/metabolismo , Animais , Proteínas Sanguíneas/farmacologia , Proteínas do Citoesqueleto/metabolismo , Hipocampo/efeitos dos fármacos , Imidazóis/farmacologia , Indazóis/farmacologia , Indóis/farmacologia , Aprendizagem/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Alvo Mecanístico do Complexo 1 de Rapamicina , Alvo Mecanístico do Complexo 2 de Rapamicina , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Plasticidade Neuronal/efeitos dos fármacos , Piperazinas/farmacologia , Polimerização/efeitos dos fármacos , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia
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