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1.
J Neurosci ; 43(37): 6401-6414, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37507230

RESUMO

Older adults exposed to enriched environments (EEs) maintain relatively higher levels of cognitive function, even in the face of compromised markers of brain health. Response speed (RS) is often used as a simple proxy to measure the preservation of global cognitive function in older adults. However, it is unknown which specific selection, decision, and/or motor processes provide the most specific indices of neurocognitive health. Here, using a simple decision task with electroencephalography (EEG), we found that the efficiency with which an individual accumulates sensory evidence was a critical determinant of the extent to which RS was preserved in older adults (63% female, 37% male). Moreover, the mitigating influence of EE on age-related RS declines was most pronounced when evidence accumulation rates were shallowest. These results suggest that the phenomenon of cognitive reserve, whereby high EE individuals can better tolerate suboptimal brain health to facilitate the preservation of cognitive function, is not just applicable to neuroanatomical indicators of brain aging but can be observed in markers of neurophysiology. Our results suggest that EEG metrics of evidence accumulation may index neurocognitive vulnerability of the aging brain.Significance Statement Response speed in older adults is closely linked with trajectories of cognitive aging. Here, by recording brain activity while individuals perform a simple computer task, we identify a neural metric that is a critical determinant of response speed. Older adults exposed to greater cognitive and social stimulation throughout a lifetime could maintain faster responding, even when this neural metric was impaired. This work suggests EEG is a useful technique for interrogating how a lifetime of stimulation benefits brain health in aging.


Assuntos
Encéfalo , Cognição , Humanos , Masculino , Feminino , Idoso , Tempo de Reação , Encéfalo/fisiologia , Cognição/fisiologia , Envelhecimento , Eletroencefalografia/métodos
2.
Skin Res Technol ; 30(4): e13679, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38616503

RESUMO

BACKGROUND: Injectable filler, a nonsurgical beauty method, has gained popularity in rejuvenating sagging skin. In this study, polydioxanone (PDO) was utilized as the main component of the ULTRACOL200 filler that helps stimulate collagenesis and provide skin radiant effects. The study aimed to evaluate and compare the effectiveness of ULTRACOL200 with other commercialized products in visually improving dermatological problems. METHODS: Herein, 31 participants aged between 20 and 59 years were enrolled in the study. 1 mL of the testing product, as well as the quantity for the compared groups was injected into each participants face side individually. Subsequently, skin texture and sunken volume of skin were measured using ANTERA 3D CS imaging technology at three periods: before the application, 4 weeks after the initial application, and 4 weeks after the 2nd application of ULTRACOL200. RESULTS: The final results of skin texture and wrinkle volume evaluation consistently demonstrated significant enhancement. Consequently, subjective questionnaires were provided to the participants to evaluate the efficacy of the testing product, illustrating satisfactory responses after the twice applications. CONCLUSION: The investigation has contributed substantially to the comprehension of a PDO-based filler (ULTRACOL200) for skin enhancement and provided profound insight for future clinical trials.


Assuntos
Sulco Nasogeniano , Transplante de Pele , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Pele/diagnóstico por imagem , Imageamento Tridimensional , Tecnologia
3.
Sheng Li Xue Bao ; 74(2): 177-187, 2022 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-35503065

RESUMO

This paper was aimed to investigate the effect of voluntary wheel running exercise on depression-like behavior induced by chronic water immersion restraint stress (CWIRS) and the underlying mechanism. Sprague-Dawley (SD) rats received CWIRS to induce depression-like behavior and 4-week voluntary wheel running exercise. Meanwhile, the rats were treated with lipopolysaccharide (LPS) or STAT3 over-expression vector (pcDNA-STAT3) by intracerebroventricular injection. Behavioral tests were used to detect depression-like behavior. ELISA assay was used to detect levels of various inflammatory factors in the rat hippocampus. Western blot was used to detect protein expression levels of ionized calcium binding adaptor molecule 1 (Iba1), inducible nitric oxide synthase (iNOS), arginase 1 (Arg1), phosphorylated STAT3 (p-STAT3) and total STAT3 (t-STAT3). The results showed that, compared with stress group, stress + exercise group exhibited improved depression-like behavior, decreased interleukin-1ß (IL-1ß) and IL-6 levels, increased IL-4 and IL-10 levels, down-regulated Iba-1 and iNOS protein expression levels, up-regulated Arg1 protein expression level, and decreased p-STAT3/t-STAT3 ratio in hippocampal tissue. LPS reversed the improving effect of voluntary wheel running exercise on depression-like behavior in rats, and the over-expression of STAT3 reversed the promoting effects of voluntary wheel running on M2 polarization of microglial cells in rat hippocampus and depression-like behavior. These results suggest that voluntary wheel running ameliorates the depression-like behavior induced by CWIRS in rats, and the mechanism may be related to regulating hippocampal microglia polarization via STAT3 signaling pathway.


Assuntos
Depressão , Microglia , Animais , Depressão/etiologia , Hipocampo/metabolismo , Lipopolissacarídeos/metabolismo , Microglia/metabolismo , Atividade Motora , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
4.
J Cogn Neurosci ; 33(6): 1020-1031, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34428789

RESUMO

Current models of perceptual decision-making assume that choices are made after evidence in favor of an alternative accumulates to a given threshold. This process has recently been revealed in human EEG recordings, but an unresolved issue is how these neural mechanisms are modulated by competing, yet task-irrelevant, stimuli. In this study, we tested 20 healthy participants on a motion direction discrimination task. Participants monitored two patches of random dot motion simultaneously presented on either side of fixation for periodic changes in an upward or downward motion, which could occur equiprobably in either patch. On a random 50% of trials, these periods of coherent vertical motion were accompanied by simultaneous task-irrelevant, horizontal motion in the contralateral patch. Our data showed that these distractors selectively increased the amplitude of early target selection responses over scalp sites contralateral to the distractor stimulus, without impacting on responses ipsilateral to the distractor. Importantly, this modulation mediated a decrement in the subsequent buildup rate of a neural signature of evidence accumulation and accounted for a slowing of RTs. These data offer new insights into the functional interactions between target selection and evidence accumulation signals, and their susceptibility to task-irrelevant distractors. More broadly, these data neurally inform future models of perceptual decision-making by highlighting the influence of early processing of competing stimuli on the accumulation of perceptual evidence.


Assuntos
Atenção , Humanos
5.
J Med Internet Res ; 23(9): e28797, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34528888

RESUMO

BACKGROUND: Although patient portals are widely used for health promotion, little is known about the use of palliative care and end-of-life (PCEOL) portal tools available for patients and caregivers. OBJECTIVE: This study aims to identify and assess the user perspectives of PCEOL portal tools available to patients and caregivers described and evaluated in the literature. METHODS: We performed a scoping review of the academic literature directed by the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) extension for Scoping Review and searched three databases. Sources were included if they reported the development or testing of a feature, resource, tool, or intervention; focused on at least one PCEOL domain defined by the National Coalition for Hospice and Palliative Care; targeted adults with serious illness or caregivers; and were offered via a patient portal tethered to an electronic medical record. We independently screened the titles and abstracts (n=796) for eligibility. Full-text (84/796, 10.6%) sources were reviewed. We abstracted descriptions of the portal tool name, content, targeted population, and reported user acceptability for each tool from included sources (n=19). RESULTS: In total, 19 articles describing 12 tools were included, addressing the following PCEOL domains: ethical or legal (n=5), physical (n=5), and psychological or psychiatric (n=2). No tools for bereavement or hospice care were identified. Studies have reported high acceptability of tools among users; however, few sources commented on usability among older adults. CONCLUSIONS: PCEOL patient portal tools are understudied. As medical care increasingly moves toward virtual platforms, future research should investigate the usability and acceptability of PCEOL patient portal resources and evaluate their impact on health outcomes.


Assuntos
Cuidados Paliativos na Terminalidade da Vida , Portais do Paciente , Assistência Terminal , Idoso , Cuidadores , Humanos , Cuidados Paliativos
6.
Biochem Biophys Res Commun ; 524(1): 77-82, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-31980179

RESUMO

OBJECTIVES: Protein arginine methyltransferase 2 (PRMT2) is closely related to the occurrence and development of atherosclerosis. However, its underlying mechanisms remain to be elucidated. The purpose of this study is to observe the effect of overexpression of PRMT2 on the formation of foam cells and to explore its possible mechanism in RAW 264.7 macrophage. METHODS: Lentivirus vector of overexpression PRMT2 (LV-PRMT2) was constructed. LV-PRMT2 and lentivirus vector GV492 were transfected into RAW 264.7 macrophages, positive clone cells were screened by treatment with 4.0 µg/mL puromycin for 4 weeks. The macrophages were treated with ox-LDL (50 µg/mL) for 48 h to induce foaming. The lipid accumulation of macrophages was observed by oil red O staining. The levels of cellular total cholesterol (TC), free cholesterol (FC) and cholesteryl ester (CE) were measured by high performance liquid chromatography (HPLC) assays. The cholesterol efflux of macrophages was tested by the [3H] labeled cholesterol. The expressions of ATP binding cassette transporter A1 (ABCA1), ATP binding cassette transporter G1 (ABCG1), CD36 and scavenger receptor A1 (SR-A1) in macrophages were measured by Western Blot. RESULTS: The results showed that LV-PRMT2 and lentivirus vector has been successfully transfected into RAW 264.7 macrophage. Compared with the Vector group, the mRNA and protein expressions of PRMT2 were significantly up-regulated (P < 0.05). Compared with Control group, the expression of PRMT2 was significantly down-regulated in ox-LDL group (P < 0.05). A large number of red lipid droplets appeared in the cells in Vector group. Compared with Vector group, lipid droplets, the levels of TC, FC and CE and CE/TC, cholesterol efflux rate and expression of ABCA1 in RAW 264.7 macrophage was significantly decreased in LV-PRMT2 group (all P < 0.05). There was no significant difference about the expressions of ABCG1, CD36 and SR-A1 between LV-PRMT2 group and Vector group (all P > 0.05). CONCLUSIONS: Overexpression of PRMT2 inhibits the formation of foam cell induced by ox-LDL in RAW 264.7 macrophage, and the mechanism may be related to the increase of ABCA1 expression and ABCA1 mediated cholesterol efflux.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/metabolismo , Células Espumosas/metabolismo , Lipoproteínas LDL/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Transportador 1 de Cassete de Ligação de ATP/genética , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Arginina/metabolismo , Aterosclerose/metabolismo , Transporte Biológico , Antígenos CD36/metabolismo , Regulação da Expressão Gênica , Lentivirus/genética , Metilação , Camundongos , Células RAW 264.7 , RNA Mensageiro/metabolismo , Receptores Depuradores/metabolismo , Transfecção
7.
Brain ; 142(3): 719-732, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30689734

RESUMO

Disorders of motivation, such as apathy, are common in Parkinson's disease, and a key feature of such disorders is a greater aversion to effort. In humans, the experience of cognitive effort is ubiquitous, and cognitive apathy has traditionally been considered distinct and separable from other subtypes. Surprisingly, however, the neurobiology of cognitive motivation is poorly understood. In particular, although dopamine has a well-characterized role in incentivizing physically effortful behaviour, a critical, unresolved issue is whether its facilitatory role generalizes to other domains. Here, we asked how dopamine modulates the willingness of patients with Parkinson's disease to invest cognitive effort in return for reward. We tested 20 patients with idiopathic Parkinson's disease across two counterbalanced sessions-ON and OFF their usual dopaminergic medication-and compared their performance to 20 healthy age-matched controls. We applied a novel task in which we manipulated cognitive effort as the number of rapid serial visual presentation streams to which participants had to attend. After training participants to ceiling performance, we then asked them to choose between a low-effort/low-reward baseline option, and a higher-effort/higher-reward offer. Computational models of choice behaviour revealed four key results. First, patients OFF medication were significantly less cognitively motivated than controls, as manifest by steeper cognitive effort discounting functions in the former group. Second, dopaminergic therapy improved this deficit, such that choices in patients ON medication were indistinguishable from controls. Third, differences in motivation were also accompanied by independent changes in the stochasticity of individuals' decisions, such that dopamine reduced the variability in choice behaviour. Finally, choices on our task correlated uniquely with the subscale of the Dimensional Apathy Scale that specifically indexes cognitive motivation, which suggests a close relationship between our laboratory measure of cognitive effort discounting and subjective reports of day-to-day cognitive apathy. Importantly, participants' choices were not confounded by temporal discounting, probability discounting, physical demand, or varying task performance. These results are the first to reveal the central role of dopamine in overcoming cognitive effort costs. They provide an insight into the computational mechanisms underlying cognitive apathy in Parkinson's disease, and demonstrate its amenability to dopaminergic therapy. More broadly, they offer important empirical support for prominent frameworks proposing a domain-general role for dopamine in value-based decision-making, and provide a critical link between dopamine and multidimensional theories of apathy.


Assuntos
Cognição/efeitos dos fármacos , Dopamina/farmacologia , Doença de Parkinson/tratamento farmacológico , Idoso , Apatia , Simulação por Computador , Tomada de Decisões , Dopamina/metabolismo , Dopaminérgicos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motivação/efeitos dos fármacos , Esforço Físico , Recompensa
8.
Bull Environ Contam Toxicol ; 103(1): 127-132, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30671617

RESUMO

This study examined the selenium (Se) and cadmium (Cd) uptake by rice from soil and analyzed the relationship between Se and Cd in naturally occurred Se-rich paddy fields with a high geological background of Cd. Significant correlations were observed between soil Se and plant biomass Se, but not between soil Cd and plant biomass Cd. High concentrations of Cd were detected in rice plants and particularly in rice grains, suggesting potential health risks to human. Contrary to results from other previous studies, our results showed that high soil Se did not reduce Cd uptake by rice, although it decreased the availability of Cd in soil. Rather, soil Se and internal Se pool in rice were positively correlated to the transfer of Cd from root to straw. The effect of Se on the uptake and translocation of Cd in rice in field is therefore different from those in pot experiments.


Assuntos
Cádmio/metabolismo , Oryza/metabolismo , Selênio/química , Poluentes do Solo/metabolismo , Transporte Biológico , Biomassa , Cádmio/análise , Raízes de Plantas/efeitos dos fármacos , Solo
9.
Opt Express ; 26(2): 1521-1529, 2018 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-29402025

RESUMO

We present a SESAM mode locked Yb:CALGO laser with a harmonic repetition rate to the 300th order pumped by a single-mode fiber coupled laser diode. By fine tuning the internal angle between the laser beam and the normal axis through the gain medium, at pump power of 1.2 W, an average output power of 132 mW is achieved with a pulse duration of 777.6 fs and a repetition rate of 22.4 GHz. The amplification effect over several tens of roundtrips induced Fabry-Perot filtering of the anti-reflection (AR) coated gain medium is analyzed. The modulation depth increases and the FWHM of a passband Δυcrystal decreases with increasing roundtrip numbers in the laser crystal. The intra-cavity pulse shaping mechanism with a comb filter caused by the amplified etalon effect of the AR coated laser crystal leads to the overall mode spacing equal to the free spectral range of the gain medium other than the laser cavity and results in the high repetition rate running.

10.
Opt Express ; 26(21): 26925-26932, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30469770

RESUMO

Double-end polarized pumping scheme combined with off-axis pumping technique has been first introduced to generate vortex beams in a z-type cavity. By employing double-end pumping, two different transverse modes can be excited simultaneously. The phase delay between these two modes can be finely tuned by manipulating the cavity structure. Direct emission of a chirality controllable Laguerre Gaussian LG01 vortex beam with slope efficiency of more than 40% has been realized by a double-end polarized pumped Yb:KYW laser. Other modes, such as dual-LG01 mode, cross-shaped mode, and LG10 mode, have also been demonstrated from our laser setup.

11.
Opt Express ; 26(14): 18164-18170, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-30114096

RESUMO

Wavelength- and OAM- tunable laser with large tunable range is the key source for the application in large capacity optical communications. In this paper, we demonstrate a wavelength- and OAM-tunable vortex laser in a 1.2 W single mode fiber coupled LD pumped Yb:phosphate laser. A z-type cavity has been used to precisely control the laser mode diameter. A thin film polarizer (TFP) is inserted to finely control the intra-cavity loss and tune the wavelength. Corresponding laser fundamental mode to pump beam ratio has been optimized to decrease the pump threshold for high order HG mode running. A pair of cylindrical lenses has been used to convert the HG mode to vortex output. The vortex beam with OAM-tunable range from 1h to 14 h with wavelength tuning range of ~36.2 nm for LG0,1 vortex beam, and ~14.5 nm for LG0,14 vortex beam at pump power of only 1.2 W have been realized, which is the largest tuning range of both OAM and wavelength at ~1 W pump power range to the best of our knowledge.

12.
Opt Express ; 26(24): 31889-31897, 2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30650768

RESUMO

We propose and demonstrate a novel flexible and elastic vibration-displacement fiber sensor with a doped polydimethylsiloxane (PDMS) micro-fiber based on model interference. High resolution three-dimensional displacement measurement is achieved through monitoring the output pattern and variation of power. The sensor with a length of about 200 µm reveals frequency range from 50 Hz to 14 kHz, covering all the human voice frequency, with greatly enhanced high signal to noise ratio (SNR) reaching up to 66 dB. This work suggests a simple structure, small size and low cost fiber-based convenient way to achieve a multifunctional sensing applications including human motion detection.

13.
Appl Opt ; 56(4): 897-900, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28158091

RESUMO

We have demonstrated a generation of double-scale in a laser diode (LD)-pumped Yb:phosphate solid-state laser. The double-scale pulse with a spectrum bandwidth of 4.6 nm is obtained at a central wavelength of 1030 nm with maximum output power of 377 mW and 80 MHz repetition rate. The autocorrelation function of the double-scale pulse contained a 510 fs short peak and 12.51 ps long pedestal. To our best knowledge, this is the first demonstration of a double-scale pulse mode-locked solid-state laser.

14.
Appl Opt ; 55(4): 929-34, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26836102

RESUMO

We theoretically and experimentally report and evaluate a novel split laser-diode (LD) double-end pumped Yb:KYW ultrafast oscillator aimed at improving the performance of an ultrafast laser. Compared to a conventional unpolarized single-LD end-pumped ultrafast laser system, we improve the laser performance such as absorption efficiency, slope efficiency, cw mode-locking threshold, and output power by this new structure LD-pumped Yb:KYW ultrafast laser. Experiments were carried out with a 1 W output fiber-coupled LD. Experimental results show that the absorption increases from 38.7% to 48.4%, laser slope efficiency increases from 18.3% to 24.2%, cw mode-locking threshold decreases 12.7% from 630 to 550 mW in cw mode-locking threshold, and maximum output-power increases 28.5% from 158.4 to 221.5 mW when we switch the pump scheme from an unpolarized single-end pumping structure to a split LD double-end pumping structure.

15.
Yao Xue Xue Bao ; 51(1): 80-5, 2016 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-27405166

RESUMO

This study aims to investigate the function of two SNPs (rs8904C > T and rs696G >A) in 3' untranslated region (3'UTR) of NFKBIA gene by constructing luciferase reporter gene. A patient's genomic DNA with rs8904 CC and rs696 GA genotype was used as the PCR template. Full-length 3'UTR of NFKBIA gene was amplified by different primers. After sequencing validation, these fragments were inserted to the luciferase reporter vector, pGL3-promoter to construct recombinant plasmids containing four kinds of haplotypes, pGL3-rs8904C/rs696G, pGL3-rs8904C/rs696A, pGL3-rs8904T/rs696G and pGL3-rs8904T/rs696A. Then these plasmids were transfected into LS174T cells and the luciferase activity was detected. Compared with pGL3-vector transfected cells (negative control), the luciferase activity of the four kinds of recombinant plasmids was significantly decreased (P < 0.001). For rs696G > A, the luciferase activity of the recombinant plasmids containing A allele (pGL3-rs8904C/rs696A and pGL3-rs8904T/rs696A) was about 45.1% (P < 0.05) and 56.1% (P < 0.001) lower than those containing G allele (pGL3-rs8904C/rs696G and pGL3-rs8904T/rs696G), respectively. For rs8904C > T, there were no significant differences in the luciferase activity between the recombinant plasmids containing T allele and those with C allele. Together, the luciferase reporter gene vectors containing SNPs in NFKBIA gene 3'UTR were constructed successfully and rs696G > A could decrease the luciferase activity while rs8904C >T didn't have much effect on the luciferase activity.


Assuntos
Genes Reporter , Vetores Genéticos , Proteínas I-kappa B/genética , Luciferases , Polimorfismo de Nucleotídeo Único , Regiões 3' não Traduzidas , Humanos , Inibidor de NF-kappaB alfa , Plasmídeos , Regiões Promotoras Genéticas , Transfecção
16.
J Neurophysiol ; 113(4): 1077-84, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25429114

RESUMO

It is well known that the central nervous system automatically reduces a mismatch in the visuomotor coordination. Can the underlying learning strategy be modified by environmental factors or a subject's learning experiences? To elucidate this matter, two groups of subjects learned to execute reaching arm movements in environments with task-irrelevant visual cues. However, one group had previous experience of learning these movements using task-relevant visual cues. The results demonstrate that the two groups used different learning strategies for the same visual environment and that the learning strategy was influenced by prior learning experience.


Assuntos
Encéfalo/fisiologia , Aprendizagem , Destreza Motora , Sinais (Psicologia) , Feminino , Mãos/inervação , Mãos/fisiologia , Humanos , Masculino , Sensação , Adulto Jovem
17.
Neurochem Res ; 40(11): 2374-82, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26453045

RESUMO

Organophosphate-induced delayed neuropathy (OPIDN) is pathologically characterized by the swollen axon containing aggregations of microtubules, neurofilaments, smooth endoplasmic reticulum and multivesicular vesicles. At present, the exact mechanism of OPIDN is unclear and the effective therapeutic methods is not available to counter this syndrome. Recent studies had shown that the autophagy was involved in OPIDN. The adipocytokine Apelin is a peptide, Apelin and its receptor are abundantly expressed in the nervous system. Recent researches illuminated that Apelin was neuroprotective factor and Apelin could regulate the autophagy in vivo and vitro model. So we investigated the effect of Apelin-13 on the OPIDN induced by Tri-ortho-cresyl phosphate (TOCP) in hens and explored the role of autophagy in Apelin-13 preventing OPIDN. Adult Roman hens were given a single dose of 750 mg/kg TOCP by gavage for 21 days to induce OPIDN, and neural dysfunction were detected, and the formation of autophagosomes in spinal cord neurons was observed by transmission electron microscopy, and the molecular markers of autophagy microtubule-associated protein light chain-3 (LC3) and the autophagy substrates p62/SQSTM1 were determined by Western blot analysis. The results demonstrated that the obvious neurological dysfunction such as hindlimb paralysis and paralysis of gait was present, the number of autophagosomes in the neurons of spinal cords was significantly increased, the level of LC3-II and p62 expressions and the ratio of LC3-II/LC3-I in spinal cords and sciatic nerve were significantly increased in the OPIDN model group compared with the control group. Compared with the OPIDN model group, the neurological dysfunction of tens was obviously reduced, the clinical signs scores was significantly decreased, the number of autophagosomes in the neurons of hen spinal cords was significantly decreased, the level of LC3-II and p62 expressions and the ratio of LC3-II/LC3-I in spinal cords and sciatic nerve were significantly decreased in Apelin-13 treatment group. Our results suggested that Apelin-13 prevented against the OPIDN induced by TOCP in hens, which the mechanism might be associated with regulation autophagy flux by Apelin-13.


Assuntos
Autofagia/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Fármacos Neuroprotetores/farmacologia , Síndromes Neurotóxicas/prevenção & controle , Tritolil Fosfatos , Animais , Galinhas , Feminino , Transtornos Neurológicos da Marcha/induzido quimicamente , Transtornos Neurológicos da Marcha/fisiopatologia , Humanos , Neurônios/metabolismo , Neurônios/patologia , Síndromes Neurotóxicas/patologia , Fagossomos/efeitos dos fármacos , Nervo Isquiático/patologia , Medula Espinal/metabolismo , Medula Espinal/patologia
18.
Appl Opt ; 54(35): 10304-8, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26836850

RESUMO

In this paper, we use a small bandwidth 808 nm cw Ti:sapphire laser as a pump source to pump a picosecond microchip laser. Different focal length pump focus lenses have been tested to improve laser efficiency. A maximum slope efficiency of around 20% is obtained by a 30 mm focal length lens. The pump threshold is only 13 mW. In order to reduce the timing jitter, we explored the self-injection seeding method by adding a seeding cavity to the microchip laser. A reduction factor in the timing jitter of up to a factor of 23 relative to the unseeded laser is obtained. From the experiments, we also found that higher seeding pulse energy will help to reduce the jitter more.

19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(9): 2483-6, 2015 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-26669152

RESUMO

Thin films of Nd:YAG and Nd:Glass were prepared on Si(100) substrate by pulsed laser deposition technology. The morphology of film surface and cross section, composition, absorption spectrum and photoluminescence (PL) spectra of films were investigated by scanning electron microscope (SEM), energy disperse spectroscopy (EDS), Fourier transform infrared spectrometer (FTIR), optical parametric oscillator (OPO) and grating spectrometer. The results show that both Nd:YAG films and Nd:Glass films grown on the substrates at room temperature are amorphous. Nd:YAG films grown by PLD contain Nd element with 0.15 at. % stoichiometric proportion. The absorption spectrum of bulk Nd:YAG target rather than deposited films exhibit two absorption peaks at 750 and 808 nm. There are no evident peaks in the photoluminescence spectra curve of Nd:YAG films. However, the photoluminescence spectra of Nd:Glass films with two sharp peaks at the wavelength of 877 and 1064 nm are observed. It indicates that Nd is doped into glass host as optically active Nd(3+) ions when Nd:Glass films grow at room temperature. But for Nd:YAG films, Nd don't incorporate into YAG host as Nd(3+) ions.

20.
IEEE J Biomed Health Inform ; 28(5): 2854-2865, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38427554

RESUMO

Automated segmentation of liver tumors in CT scans is pivotal for diagnosing and treating liver cancer, offering a valuable alternative to labor-intensive manual processes and ensuring the provision of accurate and reliable clinical assessment. However, the inherent variability of liver tumors, coupled with the challenges posed by blurred boundaries in imaging characteristics, presents a substantial obstacle to achieving their precise segmentation. In this paper, we propose a novel dual-branch liver tumor segmentation model, SBCNet, to address these challenges effectively. Specifically, our proposed method introduces a contextual encoding module, which enables a better identification of tumor variability using an advanced multi-scale adaptive kernel. Moreover, a boundary enhancement module is designed for the counterpart branch to enhance the perception of boundaries by incorporating contour learning with the Sobel operator. Finally, we propose a hybrid multi-task loss function, concurrently concerning tumors' scale and boundary features, to foster interaction across different tasks of dual branches, further improving tumor segmentation. Experimental validation on the publicly available LiTS dataset demonstrates the practical efficacy of each module, with SBCNet yielding competitive results compared to other state-of-the-art methods for liver tumor segmentation.


Assuntos
Algoritmos , Neoplasias Hepáticas , Tomografia Computadorizada por Raios X , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Fígado/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Redes Neurais de Computação , Aprendizado Profundo
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