Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 43
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
J Neuroinflammation ; 21(1): 140, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807233

RESUMO

BACKGROUND: Perihematomal edema (PHE) after post-intracerebral hemorrhage (ICH) has complex pathophysiological mechanisms that are poorly understood. The complicated immune response in the post-ICH brain constitutes a crucial component of PHE pathophysiology. In this study, we aimed to characterize the transcriptional profiles of immune cell populations in human PHE tissue and explore the microscopic differences between different types of immune cells. METHODS: 9 patients with basal ganglia intracerebral hemorrhage (hematoma volume 50-100 ml) were enrolled in this study. A multi-stage profile was developed, comprising Group1 (n = 3, 0-6 h post-ICH, G1), Group2 (n = 3, 6-24 h post-ICH, G2), and Group3 (n = 3, 24-48 h post-ICH, G3). A minimal quantity of edematous tissue surrounding the hematoma was preserved during hematoma evacuation. Single cell RNA sequencing (scRNA-seq) was used to map immune cell populations within comprehensively resected PHE samples collected from patients at different stages after ICH. RESULTS: We established, for the first time, a comprehensive landscape of diverse immune cell populations in human PHE tissue at a single-cell level. Our study identified 12 microglia subsets and 5 neutrophil subsets in human PHE tissue. What's more, we discovered that the secreted phosphoprotein-1 (SPP1) pathway served as the basis for self-communication between microglia subclusters during the progression of PHE. Additionally, we traced the trajectory branches of different neutrophil subtypes. Finally, we also demonstrated that microglia-produced osteopontin (OPN) could regulate the immune environment in PHE tissue by interacting with CD44-positive cells. CONCLUSIONS: As a result of our research, we have gained valuable insight into the immune-microenvironment within PHE tissue, which could potentially be used to develop novel treatment modalities for ICH.


Assuntos
Edema Encefálico , Hemorragia Cerebral , Progressão da Doença , Análise de Sequência de RNA , Análise de Célula Única , Humanos , Edema Encefálico/imunologia , Edema Encefálico/patologia , Edema Encefálico/genética , Edema Encefálico/metabolismo , Edema Encefálico/etiologia , Hemorragia Cerebral/imunologia , Hemorragia Cerebral/patologia , Hemorragia Cerebral/genética , Masculino , Feminino , Pessoa de Meia-Idade , Análise de Sequência de RNA/métodos , Idoso , Hematoma/patologia , Hematoma/imunologia , Hematoma/genética
2.
Opt Express ; 32(7): 12569-12586, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571076

RESUMO

According to the principle of synthetic aperture ladar, high-resolution imaging can be achieved if the relative motion exists between the target and the ladar. The imaging system has characteristics including a large field of view, narrow-band laser signals applied, and easy engineering implementation. The complex image reconstruction and the synthetic aperture laser imaging method for moving targets based on the spatial light modulator and the direct-detection detector array are proposed. The far-field simulations and the near-field experiments for the stop-and-go target and the continuous-moving target were carried out. It is verified that the complex image reconstruction method can equivalently realize coherent detection for the target and reflect its phase information corresponding to the laser wavelength. Multi-frame complex images reconstructed can be applied to the synthetic aperture laser imaging, which forms high-resolution images for moving targets under far/near-field conditions.

3.
Cell Biochem Funct ; 42(2): e3939, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38454810

RESUMO

We aimed to explore the effects of NOP16 on the pathogenesis of nasopharyngeal carcinoma (NPC) and the related mechanism. In this study, the expression level of NOP16 in NPC tissues and adjacent tissues was measured by qRT-polymerase chain reaction (PCR) and immunohistochemistry (IHC) tests. In the in vitro study, the expression levels of NOP16 and RhoA/phosphatidylinositol 3-kinase (PI3K)/Akt/c-Myc and IKK/IKB/NF-κB signalling pathway-related proteins in NPC cells were measured by qRT-PCR and Western blot (WB). CCK8 assays and colony formation assays were used to detect cell proliferation. Transwell assays were used to detect the migration and invasion ability of NPC cells. Flow cytometry and WB were used to measure the level of apoptosis. For the in vivo study, NPC xenograft models were established in nude mice, and tumour weight and volume were recorded. The expression levels of NOP16 and RhoA/PI3K/Akt/c-Myc signalling pathway-related proteins and mRNAs were measured by immunofluorescence, qRT-PCR and WB experiments. In clinical samples, the results of qRT-PCR and IHC experiments showed that the expression level of NOP16 was significantly increased in NPC tissues. In the in vitro study, the results of qRT-PCR and WB experiments showed that NOP16 was significantly increased in NPC cells. The CCK8 assay, colony formation assay, transwell assay and flow cytometry results showed that knocking out NOP16 inhibited the proliferation, migration and invasion of NPC cells and increased apoptosis. WB results showed that knocking out NOP16 inhibited the RhoA/PI3K/Akt/c-Myc and IKK/IKB/NF-κB signalling pathways. These effects were reversed by 740Y-P (PI3K activator). In the in vivo study, knockdown of NOP16 reduced tumour volume and weight and inhibited the RhoA/PI3K/Akt/c-Myc signalling pathway. In conclusion, knockdown of NOP16 inhibited the proliferation, migration and invasion of NPC cells and induced apoptosis by inhibiting the RhoA/PI3K/Akt/c-Myc and IKK/IKB/NF-κB pathways, leading to the malignant phenotype of NPC.


Assuntos
Neoplasias Nasofaríngeas , Fragmentos de Peptídeos , Proteínas Proto-Oncogênicas c-akt , Receptores do Fator de Crescimento Derivado de Plaquetas , Animais , Camundongos , Humanos , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , NF-kappa B , Camundongos Nus , Linhagem Celular Tumoral , Apoptose/genética , Proliferação de Células/genética , Movimento Celular/genética
4.
J Stroke Cerebrovasc Dis ; 33(6): 107715, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38608824

RESUMO

OBJECTIVES: This study aimed to investigate the correlations between carotid intima-media thickness (IMT) and systemic immune inflammation index (SII), platelet-to-lymphocyte ratio (PLR), and neutrophil-to-lymphocyte (NLR) ratio. MATERIALS AND METHODS: This was a cross-sectional study enrolling a total of 582 middle-aged and elderly patients. The correlations between SII, PLR, and NLR with IMT were assessed using logistic regression models, which were subsequently incorporated into the underlying models with traditional risk factors and their predictive values for IMT. RESULTS: NLR exhibited a significant correlation with IMT in the simple regression analysis (ß = 0.01, 95 %CI= 0.00-0.02, p < 0.05). After controlling for potential confounding variables in the multivariate analysis, the association between NLR and both Maximum IMT [ß = 0.04, 95 %CI = 0.02-0.07, p = 0.0006] and Mean IMT [ß = 0.05, 95 %CI = 0.02-0.07, p = 0.0001] remained statistically significant. Additionally, PLR was found to be a significant independent predictor of Maximum IMT [ß = 0.04, 95 % CI =0.00-0.07, p = 0.0242] and Mean IMT [ß = 0.04, 95 % CI = 0.01-0.07, p = 0.0061]. Similarly, SII was identified as an independent predictor of Maximum IMT [ß = 1.87, 95 % CI =1.24, p = 0.0003]. The study found a significant positive correlation between Maximum IMT and the levels NLR, PLR, and SII. Specifically, in the Maximum IMT group, higher quartiles of NLR, PLR, and SII were associated with increased odds ratios (OR) for elevated IMT levels, with statistically significant results for NLR (Q4vsQ1: OR 3.87, 95 % CI 1.81-8.29), PLR (Q4vsQ1: OR 2.84, 95 % CI 1.36-5.95), and SII (Q4vsQ1: OR 2.64, 95 % CI 1.30-5.37). Finally, the inclusion of NLR, PLR, and NLR+PLR+SII in the initial model with traditional risk factors resulted in a marginal improvement in the predictive ability for Maximum IMT, as evidenced by the net reclassification index (p < 0.05). CONCLUSIONS: This study discovered a positive correlation between SII, PLR, NLR, and IMT, which are likely to emerge as new predictors for IMT thickening. These findings lay a theoretical reference for future predictive research and pathophysiological research on carotid intima-media thickening.


Assuntos
Plaquetas , Doenças das Artérias Carótidas , Espessura Intima-Media Carotídea , Linfócitos , Neutrófilos , Valor Preditivo dos Testes , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Transversais , Idoso , Contagem de Linfócitos , Linfócitos/patologia , Contagem de Plaquetas , Fatores de Risco , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/sangue , Plaquetas/patologia , Fatores Etários , Inflamação/sangue , Inflamação/diagnóstico , Medição de Risco
5.
Appl Opt ; 62(11): 2845-2854, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37133127

RESUMO

Inverse synthetic aperture ladar (ISAL) has the capability to achieve high-resolution imaging of long-distance targets in a short time because of the laser's short wavelength. However, the unexpected phases introduced by target vibration in the echo can cause defocused imaging results of the ISAL. How to estimate the vibration phases has always been one of the difficulties in ISAL imaging. In this paper, in view of the echo's low signal-to-noise ratio, the orthogonal interferometry method based on time-frequency analysis is proposed to estimate and compensate the vibration phases of ISAL. The method can effectively suppress the influence of noise on the interferometric phases and accurately estimate vibration phases using multichannel interferometry in the inner view field. The effectiveness of the proposed method is validated through simulations and experiments, including a 1200 m distance cooperative vehicle experiment and a 250 m distance noncooperative unmanned aerial vehicle experiment.

6.
J Stroke Cerebrovasc Dis ; 32(10): 107293, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37604080

RESUMO

OBJECTIVE: To evaluate the association between remnant cholesterol (remnant-C) and intracranial atherosclerotic disease (ICAD) in the Atherosclerosis Risk in Communities Neurocognitive Study (ARIC-NCS). METHODS: We studied 1,564 participants with data on lipid profiles and high-resolution vessel wall MRI (VWMRI) from the ARIC-NCS. Remnant-C was computed as total cholesterol minus high-density lipoprotein cholesterol minus low-density lipoprotein cholesterol (LDL-C). The primary outcomes were the presence of intracranial plaques and luminal stenosis. Contributors were separated into four different groups based on remnant-C (22 mg/dL) and LDL-C (100 mg/dL) levels to investigate the function of remnant-C vs. LDL-C on ICAD. Multivariable logistic regression models were utilized to estimate the correlation among the discordant/concordant remnant-C and LDL-C, and ICAD. RESULTS: A total of 1,564 participants were included (age 76.2 ± 5.3). After multivariable adjustment, log remnant-C was correlated with greater ICAD risk [odds ratio (OR) 1.36, 95% confidence interval (CI) 1.01 to 1.83]. The lower remnant-C/higher LDL-C group and the higher remnant-C/lower LDL-C group manifested a 1.53-fold (95% CI 1.06 to 2.20) and 1.52-fold (95% CI 1.08 to 2.14) greater risk of ICAD, relative to those having lower remnant-C/low LDL-C. Additionally, remnant-C ≥ 22 mg/dL distinguished participants at a greater risk of the presence of any stenosis compared to those at lower levels, even in participants with optimal levels of LDL-C. CONCLUSIONS: Elevated levels of remnant-C were connected to ICAD independent of LDL-C and traditional risk factors. The mechanisms of remnant-C association with ICAD probably offer insight into preventive risk-factor of ischemic stroke.


Assuntos
Aterosclerose , Arteriosclerose Intracraniana , Humanos , Idoso , Idoso de 80 Anos ou mais , LDL-Colesterol , Constrição Patológica , Colesterol , Fatores de Risco , Aterosclerose/diagnóstico por imagem , Aterosclerose/epidemiologia , Arteriosclerose Intracraniana/diagnóstico por imagem , Arteriosclerose Intracraniana/epidemiologia
7.
Opt Lett ; 47(20): 5356-5359, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36240361

RESUMO

According to the self-heterodyne signal obtained by lidar under different fiber delay times, the model of the local oscillator signal was established, and the maintenance method of signal coherence in lidar based on the digital delay was improved by using multiple sinusoidal frequency modulation components. An imaging detection experiment was carried out at a distance of 5.4 km. The coherence of the lidar signal was maintained by combining the transmitting reference channel correction method and the local oscillator reference channel compensation method, accompanied by the use of a phase spectrum to analyze the improvement effect. The processing results of the echo signal showed that the method could remove the high-order phase errors that cannot be compensated by the phase gradient autofocus algorithm and improve the signal coherence, which could be used for the detection and imaging of long-range targets.

8.
Appl Opt ; 61(34): 10080-10085, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36606767

RESUMO

Aiming at the wide-spectrum chromatic aberration problem of membrane diffractive lenses, the concept of the digital chromatic aberration correction infrared imaging system was proposed. The principle of digital chromatic aberration correction was given, and the chromatic aberration correction of this system was completed on a computer, which is based on a wavelength-tunable laser local oscillator coherent detection detector. Compared with the chromatic aberration correction method for traditional lenses, this membrane diffractive optical system exhibited characteristics of small size, low weight, and low complexity. The digital chromatic aberration correction application conditions of this membrane diffractive optical system were analyzed. In addition, the main parameters and imaging simulation results were given. The center wavelength of this membrane diffractive optical system is 1.55 µm, and its spectral range is 1.50-1.60 µm. The application of autocorrelation processing to infrared complex images after digital chromatic aberration correction followed by incoherent accumulation of the received corrected complex images based on multiple stepping wavelengths could significantly improve the imaging signal-to-noise ratio.

9.
J Immunol ; 200(5): 1618-1626, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29378913

RESUMO

Inflammation that complicates many autoimmune diseases, such as multiple sclerosis (MS), has been correlated to abnormal differentiation of Th17 cells. However, the reasons that promote Th17 cell-driven autoimmunity are yet to be discovered. In this study, we sought evidence that DNA-damage-inducible transcript 4 (DDIT4) and its associated long noncoding RNA DDIT4 (lncDDIT4) inhibit Th17 cell differentiation. We recruited 36 patients. Six MS patients and five healthy volunteers (controls) contributed PBMCs as material for microarray analysis. Microarray assays of lncDDIT4 and DDIT4 RNA expression identified outstanding differences between MS and control subjects, which were verified with real-time quantitative PCR. We then interrupted the expression of lncDDIT4 and DDIT4 mRNA in MS patients' naive CD4+ T cells and observed the resulting changes in Th17 cells. The expression of lncDDIT4 and DDIT4 mRNA were higher both in PBMCs and CD4+ T cells of MS patients than in healthy controls. DDIT4 (2.79-fold upregulation) was then recognized as a candidate for the cis-regulated target of lncDDIT4 (4.32-fold upregulation). Isolation of naive CD4+ T cells revealed enhanced levels of lncDDIT4 and DDIT4 after stimulated with Th17-inducing cytokines, but not after Th1, Th2, or T regulatory cell induction. Overexpression of lncDDIT4 in naive CD4+ T cells inhibited IL-17 transcription through increased DDIT4 expression and decreased activation of the DDIT4/mTOR pathway. Consistently, silencing lncDDIT4 in naive CD4+ T cells enhanced Th17 differentiation through increased activation of the DDIT4/mTOR pathway. However, these results vanished when DDIT4 was silenced. This outcome suggests that lncDDIT4 regulates Th17 cell differentiation by directly targeting DDIT4.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Diferenciação Celular/fisiologia , RNA Longo não Codificante/metabolismo , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Células Th17/metabolismo , Fatores de Transcrição/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Citocinas/metabolismo , Humanos , RNA Mensageiro/metabolismo , Linfócitos T Reguladores/metabolismo , Células Th2/metabolismo , Regulação para Cima/fisiologia
10.
Proc Natl Acad Sci U S A ; 114(30): E6202-E6211, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28696300

RESUMO

The nonneural cholinergic system of immune cells is pivotal for the maintenance of immunological homeostasis. Here we demonstrate the expression of choline acetyltransferase (ChAT) and cholinergic enzymes in murine natural killer (NK) cells. The capacity for acetylcholine synthesis by NK cells increased markedly under inflammatory conditions such as experimental autoimmune encephalomyelitis (EAE), in which ChAT expression escalated along with the maturation of NK cells. ChAT+ and ChAT- NK cells displayed distinctive features in terms of cytotoxicity and chemokine/cytokine production. Transfer of ChAT+ NK cells into the cerebral ventricles of CX3CR1-/- mice reduced brain and spinal cord damage after EAE induction, and decreased the numbers of CNS-infiltrating CCR2+Ly6Chi monocytes. ChAT+ NK cells killed CCR2+Ly6Chi monocytes directly via the disruption of tolerance and inhibited the production of proinflammatory cytokines. Interestingly, ChAT+ NK cells and CCR2+Ly6Chi monocytes formed immune synapses; moreover, the impact of ChAT+ NK cells was mediated by α7-nicotinic acetylcholine receptors. Finally, the NK cell cholinergic system up-regulated in response to autoimmune activation in multiple sclerosis, perhaps reflecting the severity of disease. Therefore, this study extends our understanding of the nonneural cholinergic system and the protective immune effect of acetylcholine-producing NK cells in autoimmune diseases.


Assuntos
Acetilcolina/metabolismo , Sistema Nervoso Central/patologia , Encefalomielite/patologia , Células Matadoras Naturais/fisiologia , Macrófagos/fisiologia , Monócitos/fisiologia , Animais , Encefalomielite/imunologia , Humanos , Células Matadoras Naturais/metabolismo , Camundongos , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Sistema Colinérgico não Neuronal/imunologia , Sistema Colinérgico não Neuronal/fisiologia
11.
J Immunol ; 198(7): 2626-2639, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28228555

RESUMO

IL-17-producing Th17 cells have gradually become considered as key factors in the pathogenesis of many autoimmune diseases, including multiple sclerosis (MS). Although the involvement of certain microRNAs in the development of MS has been reported, their role in Th17-driven autoimmunity is still poorly understood. In this study, we identified microRNA (miR)-15b as an important factor in Th17-associated effects and determined that the expression of miR-15b is significantly downregulated in MS patients and in mice with experimental autoimmune encephalomyelitis. Overexpression of miR-15b alleviated experimental autoimmune encephalomyelitis, whereas knockdown of miR-15b aggravated it. We demonstrated that miR-15b suppressed Th17 differentiation both in vivo and in vitro. We also found that O-linked N-acetylglucosamine transferase is a potential target of miR-15b, enabling it to affect the transcriptional regulation of retinoic acid-related orphan receptor γT through O-linked N-acetylglucosamine glycosylation of NF-κB. These results contribute to the importance of miR-15b in Th17 differentiation and the pathogenesis of MS.


Assuntos
Regulação da Expressão Gênica/imunologia , MicroRNAs/imunologia , Esclerose Múltipla/imunologia , N-Acetilglucosaminiltransferases/biossíntese , Células Th17/imunologia , Animais , Western Blotting , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Separação Celular , Regulação para Baixo , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Citometria de Fluxo , Técnicas de Silenciamento de Genes , Humanos , Imunoprecipitação , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Esclerose Múltipla/genética , N-Acetilglucosaminiltransferases/imunologia , Reação em Cadeia da Polimerase em Tempo Real
12.
Appl Opt ; 58(15): 3974-3985, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31158148

RESUMO

While imaging geosynchronously orbiting objects with ground-based inverse synthetic aperture LADAR (ISAL), target rotation and vibration will introduce phase errors into the echo and cause the two-dimensional imaging result to be defocused. To solve this problem, one layout of the ISAL receiving channels is designed, combining the orthogonal short baselines in the inner field with the orthogonal long baselines in the external field. On this basis, an imaging method based on orthogonal interferometry processing is proposed. The proposed method estimates and compensates for the phase errors introduced by the rotation and vibration of the target such that the focus of the two-dimensional image is improved, and three-dimensional imaging results with high accuracy are obtained. The effectiveness of the proposed method is verified by simulation data.

13.
Hum Reprod ; 33(6): 1183-1190, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29697801

RESUMO

STUDY QUESTION: Do PATL2 mutations account for female infertility with oocyte germinal vesicle (GV) arrest? SUMMARY ANSWER: Four of nine independent families with oocyte GV arrest were identified with biallelic PATL2 mutations, suggesting that these mutations may be responsible for oocyte maturation arrest in primary infertile women. WHAT IS KNOWN ALREADY: Recently, two independent studies have demonstrated that infertility in some women with oocyte maturation arrest at the GV stage was caused by biallelic mutations in PATL2. PATL2 encodes protein PAT1 homolog 2, an RNA-binding protein that may act as a translational repressor. STUDY DESIGN, SIZE, DURATION: In this study, nine unrelated primary infertile females presenting with oocyte GV arrest were recruited during the treatment of early rescue ICSI or ICSI from January 2013 to December 2016. PARTICIPANTS/MATERIALS, SETTING, METHODS: Genomic DNA was isolated from blood samples obtained from all nine affected individuals and all of their available family members. All the coding regions of PATL2 were sequenced by Sanger sequencing. The pathogenicity of the identified variants and their possible effects on the protein were evaluated in silico. MAIN RESULTS AND THE ROLE OF CHANCE: Five novel point mutations and one recurrent splicing mutation in PATL2 were identified in four of nine (44.4%) unrelated patients. We found a consanguineous family with a homozygous missense mutation in two affected sisters, and their fertile brother. There were no clear phenotypic differences in oocytes between the patient with the homozygous missense mutation, patients with nonsense mutations and undiagnosed patients. LARGE SCALE DATA: n/a. LIMITATIONS, REASONS FOR CAUTION: The function of PATL2 remains largely unknown. Both the exact pathogenic mechanism(s) of mutated PATL2 causing human oocyte maturation arrest and the strategies to overcome this condition should be further investigated in the future. WIDER IMPLICATIONS OF THE FINDINGS: According to our data, mutations in PATL2 account for 44.4% of the individuals with oocyte GV arrest. Our study further confirms that PATL2 is required for human oocyte maturation and female fertility, which indicates a potential prognostic value of testing for PATL2 mutations in primary infertile women with oocyte maturation arrest. STUDY FUNDING/COMPETING INTEREST(S): Natural Science Foundation of Anhui Province (1808085MH241), National Natural Science Foundation of China (81401251 and 81370757) and Central Guided Local Development of Science and Technology Special Fund (2016080802D114) supported this study. None of the authors have any competing interests.


Assuntos
Proteínas de Ligação a DNA/genética , Infertilidade Feminina/genética , Oócitos/patologia , Mutação Puntual/genética , Adulto , Consanguinidade , Proteínas de Ligação a DNA/sangue , Feminino , Humanos , Infertilidade Feminina/diagnóstico , Oócitos/metabolismo , Irmãos
14.
Opt Lett ; 43(6): 1222-1225, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29543256

RESUMO

Internal polarization dynamics of vector dissipative-soliton-resonance (DSR) pulses in a mode-locked fiber laser are investigated. By utilizing a wave plate analyzer configuration to analyze the special structure of a DSR pulse, we find that polarization state is not uniform across a resonant dissipative soliton. Specifically, although the central plane wave of the resonant dissipative soliton acquires nearly a single fixed polarization, the dissipative fronts feature polarization states that are different and spatially varying. This distinct polarization distribution is maintained while the whole soliton extends with increasing gain. Numerical simulation further confirms the experimental observations.

15.
Appl Opt ; 57(22): 6481-6490, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30117881

RESUMO

Target vibration introduces unexpected vibration phases in the echo signal of inverse synthetic aperture LADAR (ISAL). The vibration phases cause the imaging results to be defocused. How to estimate the vibration phases has always been one of the difficulties in ISAL imaging, and there has not been an effective solution. In this paper, two methods are proposed to estimate the vibration phases in different situations. The method based on multi-channel along-track interferometry (MCATI method) is for some cases that the target velocity vector is parallel to some baselines of ISAL. The method based on orthogonal interferometry (OI method) is for other cases that the target velocity vector is not parallel to any baseline of ISAL. In addition, a high signal to noise ratio (SNR) is essential for the MCATI and OI methods to get high estimation accuracy. Therefore, a large power-aperture product should be carefully considered in the ISAL system design. Furthermore, on the condition of low SNR, range cell accumulation is also helpful to reduce the influence of noise. Take the ISAL, which is utilized to image the satellite in 500 km orbit, as an example, the estimation accuracy can satisfy the demand of synthetic aperture imaging with 0 dB single-pulse SNR and 300 range cell accumulation. The proposed methods are verified with simulation and experiment.

16.
FASEB J ; 30(10): 3388-3399, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27342766

RESUMO

Inflammatory factors secreted by microglia play an important role in focal ischemic stroke. The mammalian target of rapamycin (mTOR) pathway is a known regulator of immune responses, but the role that mTORC1 signaling plays in poststroke neuroinflammation is not clear. To explore the relationship between microglial action in the mTORC1 pathway and the impact on stroke, we administered the mTORC1 inhibitors sirolimus and everolimus to mice. Presumably, disrupting the mTORC1 pathway after focal ischemic stroke should clarify the subsequent activity of microglia. For that purpose, we generated mice deficient in the regulatory associated protein of mTOR (Raptor) in microglia, whose mTORC1 signaling was blocked, by crossing Raptor loxed (Raptorflox/flox) mice with CX3CR1CreER mice, which express Cre recombinase under the control of the CX3C chemokine receptor 1 promoter. mTORC1 blockade reduced lesion size, improved motor function, dramatically decreased production of proinflammatory cytokines and chemokines, and reduced the number of M1 type microglia. Thus, mTORC1 blockade apparently attenuated behavioral deficits and poststroke inflammation after middle cerebral artery occlusion by preventing microglia polarization toward the M1 type.-Li, D., Wang, C., Yao, Y., Chen, L., Liu, G., Zhang, R., Liu, Q., Shi, F.-D., Hao, J. mTORC1 pathway disruption ameliorates brain inflammation following stroke via a shift in microglia phenotype from M1 type to M2 type.


Assuntos
Encefalite/metabolismo , Macrófagos/metabolismo , Microglia/metabolismo , Complexos Multiproteicos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Comportamento Animal/fisiologia , Isquemia Encefálica/metabolismo , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos Transgênicos , Complexos Multiproteicos/genética , Transdução de Sinais/fisiologia , Acidente Vascular Cerebral/metabolismo , Serina-Treonina Quinases TOR/genética
17.
Reprod Biomed Online ; 35(3): 305-310, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28652098

RESUMO

Mutations in the tubulin beta 8 class VIII (TUBB8) gene have been proven to cause oocyte maturation arrest. The aim of this study was to describe newly discovered mutations in TUBB8 and to investigate the prevalence of TUBB8 mutations in our cohort. Nine women with oocyte maturation arrest and 100 fertile female controls were recruited. Sanger sequencing of the coding regions of TUBB8 revealed a heterozygous variant c.535G > A (p.V179M) in two unrelated affected individuals and a heterozygous variant c.5G > T (p.R2M) in one affected individual. These TUBB8 variants were inherited from the unaffected fathers and were absent in 100 fertile female control individuals. In total, 33.33% (3/9) of the affected individuals in our cohort obtained a clear genetic diagnosis through sequencing of the TUBB8 gene. These two novel variants extend the spectrum of TUBB8 mutations and this study confirmed that TUBB8 mutations occur in a high proportion of infertile women with oocyte maturation arrest.


Assuntos
Infertilidade Feminina/genética , Oócitos/fisiologia , Oogênese/genética , Tubulina (Proteína)/genética , Adulto , Estudos de Casos e Controles , Pontos de Checagem do Ciclo Celular/genética , Análise Mutacional de DNA , Feminino , Heterozigoto , Humanos , Técnicas de Maturação in Vitro de Oócitos , Masculino , Mutação , Injeções de Esperma Intracitoplásmicas , Falha de Tratamento
18.
Appl Opt ; 56(27): 7756-7765, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-29047758

RESUMO

To improve the target detection performance of inverse synthetic aperture ladar (ISAL) under the situation that there is Doppler bandwidth ambiguity, we consider energy accumulation of echo signals along a range through matched illumination. However, since the target impulse responses change with the target aspect angle, the phase shifts along slow-time between range cells are different, and the output of matched illumination fluctuates along slow-time. To reduce the slow-time fluctuation of matched illumination under additive white Gaussian noise assumption, we have proposed an interferometric ISAL (InISAL) target detection method based on interferometry processing and principal component analysis (PCA) in this paper. After the interferometry processing, the interferometric phase shifts along slow-time of all range cells are approximately the same. Then PCA is introduced to reduce the impact of noise, interference, and cross-terms of interferometry processing. Thus, the slow-time fluctuation of matched illumination can be decreased, and the target detection performance is improved. The proposed method has been validated with both simulated data of InISAL and real data of millimeter-wave interferometric synthetic aperture radar.

19.
J Neuroinflammation ; 13(1): 192, 2016 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-27549161

RESUMO

BACKGROUND: Microglia/macrophages play a critical role in the inflammatory and immune processes of cerebral ischemia/reperfusion injury. Since microglia/macrophages can reversibly shift their phenotype toward either a "detrimental" or a "restorative" state in the injured central nervous system (CNS), compounds mediate that shift which could inhibit inflammation and restore the ability to alleviate cerebral ischemia/reperfusion injury would have therapeutic potential. METHODS: Transient middle cerebral artery occlusion was induced in male C57BL/6 mice. Mice were randomly separated into a sham-operated group, a control group, and a ZSTK474-treated group. We investigated the effect of ZSTK474 by assessing neurological deficits, infarct volume, and histopathological changes. We then determined the potential mechanism by immunofluorescent staining, quantitative real-time polymerase chain reaction (PCR), and Western blot analysis. The Tukey's test or Mann-Whitney U test was used to compare differences among the groups. RESULTS: ZSTK474 alleviated neurological deficits and reduced infarct volume in the cerebral ischemia/reperfusion injury model. Presumably, ZSTK474 shifted the phenotype of microglia/macrophages to a restorative state, since this treatment decreased the secretion of pro-inflammatory factors and advanced the secretion of anti-inflammatory factors. These neuroprotective properties of ZSTK474 may be mediated by the phosphoinositide 3-kinase (PI3K)/AKT/mammalian target of rapamycin complex 1 (mTORC1) pathway. CONCLUSIONS: ZSTK474 can mediate a shift in microglia/macrophage phenotype and inhibit the inflammatory response in cerebral ischemia reperfusion injury of mice. These effects appeared to ensue via the PI3K/AKT/mTORC1 pathway. Therefore, ZSTK474 may represent a therapeutic intervention with potential for circumventing the catastrophic aftermath of ischemic stroke.


Assuntos
Isquemia Encefálica/complicações , Inflamação , Macrófagos/efeitos dos fármacos , Microglia/efeitos dos fármacos , Traumatismo por Reperfusão , Triazinas/farmacologia , Triazinas/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antígenos CD/metabolismo , Infarto Encefálico/tratamento farmacológico , Infarto Encefálico/etiologia , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Inflamação/tratamento farmacológico , Inflamação/etiologia , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doenças do Sistema Nervoso/tratamento farmacológico , Doenças do Sistema Nervoso/etiologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Transdução de Sinais/efeitos dos fármacos
20.
Opt Express ; 23(20): 25889-95, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26480103

RESUMO

We report on the observation of both stable dissipative solitons and noise-like pulses with the presence of strong Raman scattering in a relatively short all-normal-dispersion Yb-doped fiber laser. We show that Raman scattering can be filtered out by intracavity filter. Furthermore, by appropriate intracavity polarization control, the Raman effect can be utilized to generate broadband noise-like pulses (NLPs) with bandwidth up to 61.4 nm. To the best of our knowledge, this is the broadest NLP achieved in all-normal-dispersion fiber lasers.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA