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1.
bioRxiv ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38562871

RESUMO

Optogenetics allows manipulation of neural circuits in vivo with high spatial and temporal precision. However, combining this precision with control over a significant portion of the brain is technologically challenging (especially in larger animal models). Here, we have developed, optimised, and tested in vivo, the Utah Optrode Array (UOA), an electrically addressable array of optical needles and interstitial sites illuminated by 181 µLEDs and used to optogenetically stimulate the brain. The device is specifically designed for non-human primate studies. Thinning the combined µLED and needle backplane of the device from 300 µm to 230 µm improved the efficiency of light delivery to tissue by 80%, allowing lower µLED drive currents, which improved power management and thermal performance. The spatial selectivity of each site was also improved by integrating an optical interposer to reduce stray light emission. These improvements were achieved using an innovative fabrication method to create an anodically bonded glass/silicon substrate with through-silicon vias etched, forming an optical interposer. Optical modelling was used to demonstrate that the tip structure of the device had a major influence on the illumination pattern. The thermal performance was evaluated through a combination of modelling and experiment, in order to ensure that cortical tissue temperatures did not rise by more than 1°C. The device was tested in vivo in the visual cortex of macaque expressing ChR2-tdTomato in cortical neurons. It was shown that the strongest optogenetic response occurred in the region surrounding the needle tips, and that the extent of the optogenetic response matched the predicted illumination profile based on optical modelling - demonstrating the improved spatial selectivity resulting from the optical interposer approach. Furthermore, different needle illumination sites generated different patterns of low-frequency potential (LFP) activity.

2.
Commun Biol ; 7(1): 329, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485764

RESUMO

Optogenetics has transformed studies of neural circuit function, but remains challenging to apply to non-human primates (NHPs). A major challenge is delivering intense, spatiotemporally-precise, patterned photostimulation across large volumes in deep tissue. Such stimulation is critical, for example, to modulate selectively deep-layer corticocortical feedback circuits. To address this need, we have developed the Utah Optrode Array (UOA), a 10×10 glass needle waveguide array fabricated atop a novel opaque optical interposer, and bonded to an electrically addressable µLED array. In vivo experiments with the UOA demonstrated large-scale, spatiotemporally precise, activation of deep circuits in NHP cortex. Specifically, the UOA permitted both focal (confined to single layers/columns), and widespread (multiple layers/columns) optogenetic activation of deep layer neurons, as assessed with multi-channel laminar electrode arrays, simply by varying the number of activated µLEDs and/or the irradiance. Thus, the UOA represents a powerful optoelectronic device for targeted manipulation of deep-layer circuits in NHP models.


Assuntos
Neurônios , Optogenética , Animais , Eletrodos , Neurônios/fisiologia , Primatas/fisiologia , Utah
3.
Res Sq ; 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36909489

RESUMO

Optogenetics has transformed studies of neural circuit function, but remains challenging to apply in non-human primates (NHPs). A major challenge is delivering intense and spatially precise patterned photostimulation across large volumes in deep tissue. Here, we have developed and validated the Utah Optrode Array (UOA) to meet this critical need. The UOA is a 10×10 glass waveguide array bonded to an electrically-addressable µLED array. In vivo electrophysiology and immediate early gene (c-fos) immunohistochemistry demonstrated the UOA allows for large-scale spatiotemporally precise neuromodulation of deep tissue in macaque primary visual cortex. Specifically, the UOA permits both focal (single layers or columns), and large-scale (across multiple layers or columns) photostimulation of deep cortical layers, simply by varying the number of simultaneously activated µLEDs and/or the light irradiance. These results establish the UOA as a powerful tool for studying targeted neural populations within single or across multiple deep layers in complex NHP circuits.

4.
Front Behav Neurosci ; 16: 943900, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910680

RESUMO

Preclinical studies have clearly indicated that offspring of mothers who suffered sleep deprivation during pregnancy exhibit anxiety, depression-like behaviors, and cognitive deficits. The cognitive impairment induced by maternal sleep deprivation (MSD) is currently poorly treated. Growing evidence indicates that an enriched environment (EE) improves cognition function in models of Alzheimer's disease, schizophrenia, and lipopolysaccharide. However, the effects of EE on hippocampal-dependent learning and memory, as well as synaptic plasticity markers changes induced by MSD, are unclear. In the present study, pregnant CD-1 mice were randomly divided into a control group, MSD group, and MSD+EE group. Two different living environments, including standard environment and EE, were prepared. When male and female offspring were 2 months, the open field test and elevated plus maze were used to assess anxiety-like behavior, and the Morris water maze was used to evaluate hippocampal learning and memory. Western blotting and real-time fluorescence quantitative polymerase chain reaction were used to detect the expression of brain-derived neurotrophic factor and Synaptotagmin-1 in the hippocampus of offspring. The results revealed that MSD-induced offspring showed anxiety-like behaviors and cognitive impairment, while EE alleviated anxiety-like behavior and cognitive impairment in offspring of the MSD+EE group. The cognitive impairment induced by MSD was associated with a decreased brain-derived neurotrophic factor and an increased Synaptotagmin-1, while EE increased and decreased brain-derived neurotrophic factor and Synaptotagmin-1 in the hippocampus of mice from the MSD+EE group, respectively. Taken together, we can conclude that EE has beneficial effects on MSD-induced synaptic plasticity markers changes and can alleviate anxiety-like behaviors and cognitive impairment.

5.
Neurophotonics ; 6(3): 035010, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31528655

RESUMO

We present an electrically addressable optrode array capable of delivering light to 181 sites in the brain, each providing sufficient light to optogenetically excite thousands of neurons in vivo, developed with the aim to allow behavioral studies in large mammals. The device is a glass microneedle array directly integrated with a custom fabricated microLED device, which delivers light to 100 needle tips and 81 interstitial surface sites, giving two-level optogenetic excitation of neurons in vivo. Light delivery and thermal properties are evaluated, with the device capable of peak irradiances > 80 mW / mm 2 per needle site. The device consists of an array of 181 80 µ m × 80 µ m 2 microLEDs, fabricated on a 150 - µ m -thick GaN-on-sapphire wafer, coupled to a glass needle array on a 150 - µ m thick backplane. A pinhole layer is patterned on the sapphire side of the microLED array to reduce stray light. Future designs are explored through optical and thermal modeling and benchmarked against the current device.

6.
J BUON ; 24(2): 622-627, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31128015

RESUMO

PURPOSE: Hepatocellular carcinoma causes considerable mortality and no efficient chemotherapy is available. Novel molecules of plant origin may prove beneficial in the development of therapy of hepatocellular carcinoma. In this study we examined the anticancer effects of Tanshindiol-C (TC) against the hepatocellular carcinoma SNU-4235 cell line. METHODS: Proliferation rate of the SNU-2435 cells was determined by MTT assay. Apoptosis was confirmed by DAPI and annexin V/PI staining. Cell cycle analysis was performed by flow cytometry. MicroRNA expression was checked by qRT-PCR and protein expression by western blotting. The in vivo evaluation of TC was performed in xenografted mice models. RESULTS: TC inhibited the growth of the SNU-4235 cells and exhibited an IC50 of 20 µM. Investigation of the underlying mechanism revealed that TC triggered apoptotic death of the SNU-4235 cells which was also associated with enhancement of the expression of Bax and decrease in the expression of Bcl-2. TC also caused arrest of the cells in the G2/M phase of the cell cycle and also exerted angiogenitic effects. TC also enhanced the expression of the tumor suppressor microRNA-21, 222 and 31. In vivo evaluation of TC revealed that it could inhibit the tumor weight volume, suggestive of the anticancer potential of TC. CONCLUSIONS: In brief, tanshindiol-C exerts anticancer effects on hepatocellular carcinoma by induction of apoptosis and cell cycle arrest, along with inhibiting the angiogenesis and the expression of tumor suppressive microRNAs. TC could also inhibit the growth of the xenografted tumors and hence could prove to be a potential anticancer agent.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Diterpenos/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Compostos Fitoquímicos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Potencial da Membrana Mitocondrial , Camundongos , MicroRNAs/genética , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína X Associada a bcl-2/genética
7.
Biosci Rep ; 39(1)2019 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-30355645

RESUMO

BACKGROUND: Accumulating studies discloses that long non-coding RNAs (lncRNAs) serve important roles in human tumorigenesis, including nasopharyngeal carcinoma (NPC). The purpose of the present study was to determine the role of lncRNA FEZF1-AS1 in NPC. MATERIALS AND METHODS: The expression levels of FEZF1-AS1 in NPC tissues and cell lines were detected by RT-qPCR analysis. MTT assay was performed to investigate the proliferation of NPC cells in vitro, whereas the migration and invasion of NPC cells were determined by wound healing assay and transwell assay. A nude mouse tumor model was established to study the role of FEZF1-AS1 in NPC tumorigenesis in vivo The expression levels of proteins were detected by Western blot assay. RESULTS: The results showed that FEZF1-AS1 expression was increased in the NPC tissues and cell lines, and the higher expression of FEZF1-AS1 was closely associated with poor prognosis of NPC patients. We further observed that knockdown of FEZF1-AS1 inhibited the proliferation of NPC cells in vitro and suppressed NPC xenograft growth in vivo through inducing G2/M cell cycle arrest. The migratory and invasive abilities of NPC cells were also reduced upon FEZF1-AS1 knockdown. Moreover, we demonstrated that inhibition of FEZF1-AS1 remarkably suppressed epithelial-mesenchymal transition (EMT) and reduced ß-catenin accumulation in nucleus in NPC cells. CONCLUSIONS: Collectively, we showed that FEZF1-AS1 might be a key regulator of cell cycle, EMT and Wnt/ß-catenin signaling in NPC cells, which may be helpful for understanding of pathogenesis of NPC.


Assuntos
Transição Epitelial-Mesenquimal/genética , Fatores de Transcrição/genética , Via de Sinalização Wnt/genética , beta Catenina/genética , Animais , Carcinogênese/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Camundongos Nus , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patologia , RNA Longo não Codificante/genética , Proteínas Repressoras
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