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1.
Opt Express ; 32(5): 7448-7462, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439424

RESUMO

Optofluidic systems, integrating microfluidic and micro-optical technologies, have emerged as transformative tools for various applications, from molecular detection to flow cytometry. However, existing optofluidic microlenses often rely on external forces for tunability, hindering seamless integration into systems. This work presents an approach using two-photon polymerization (TPP) to fabricate inherently tunable microlens arrays, eliminating the need for supplementary equipment. The optofluidic design incorporates a three-layered structure enabling dynamic manipulation of refractive indices within microchannels, leading to tunable focusing characteristics. It is shown that the TPP fabricated optofluidic microlenses exhibit inherent tunable focal lengths, numerical apertures, and spot sizes without reliance on external forces. This work signifies some advancements in optofluidic technology, offering precise and tunable microlenses with potential applications in adaptive imaging and variable focal length microscopy.

2.
Support Care Cancer ; 32(7): 469, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940963

RESUMO

PURPOSE: Fear of progression (FoP) leads to poor clinical outcomes in colorectal cancer patients. The study aimed to clarify the profiles and influencing factors of FoP among colorectal cancer patients. METHODS: A cross-sectional study was conducted with 409 colorectal cancer patients. Convenience sampling method was used to select colorectal cancer patients hospitalized in a tertiary-level hospital in Nanjing as the survey subjects. General information questionnaire, Fear of Progression Questionnaire-Short Form, Distress Disclosure Index, and Social Support Rating Scale were used to collect the data. Latent profile analysis was used to explore the latent profiles of FoP in colorectal cancer patients. Additionally, the influencing factors of profiles were explored by Univariate Analysis and Binomial Logistic Regression Analysis. RESULTS: Latent profile analysis identified two subgroups of fear of disease progression: the "fear low-risk profile (83%)", and the "severe fear profile (17%)." Patients with low age, low social support utilization, first hospital admission, severe healthcare burden, and preoperative bowel symptoms were prone to severe fear of disease progression. CONCLUSIONS: There is some heterogeneity in the level of postoperative fear of disease progression in colorectal cancer patients. Doctors and nurses should focus on patients with severe fear and take targeted preventive and psychological care for patients' fear of disease progression as early as possible according to the distribution characteristics of different categories.


Assuntos
Neoplasias Colorretais , Progressão da Doença , Medo , Apoio Social , Humanos , Neoplasias Colorretais/psicologia , Neoplasias Colorretais/patologia , Masculino , Feminino , Estudos Transversais , Medo/psicologia , Pessoa de Meia-Idade , Idoso , Inquéritos e Questionários , Adulto , China
3.
J Integr Neurosci ; 23(5): 91, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38812394

RESUMO

Alzheimer's disease (AD), a primary cause of dementia, is rapidly emerging as one of the most financially taxing, lethal, and burdensome diseases of the 21st century. Increasing evidence suggests that microglia-mediated neuroinflammation plays a key role in both the initiation and progression of AD. Recently, emerging evidence has demonstrated mitochondrial dysfunction, particular in microglia where precedes neuroinflammation in AD. Multiple signaling pathways are implicated in this process and pharmaceutical interventions are potentially involved in AD treatment. In this review, advance over the last five years in the signaling pathways and pharmaceutical interventions are summarized and it is proposed that targeting the signaling pathways in microglia with mitochondrial dysfunction could represent a novel direction for AD treatment.


Assuntos
Doença de Alzheimer , Microglia , Mitocôndrias , Doença de Alzheimer/metabolismo , Doença de Alzheimer/terapia , Doença de Alzheimer/tratamento farmacológico , Humanos , Microglia/metabolismo , Animais , Mitocôndrias/metabolismo , Doenças Neuroinflamatórias/metabolismo , Transdução de Sinais/fisiologia
4.
J Therm Biol ; 122: 103883, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38875961

RESUMO

Melatonin (MT) is an amine hormone secreted by the body that has antioxidant and anti-inflammatory properties. The aim of this study was to investigate pathophysiological protection of MT in heat-stressed chickens. By modelling heat-stressed chickens and treating them with MT. After 21 days of administration, serum antioxidant enzymes, biochemical indices, inflammatory cytokine and heat-stress indices were detected, along with cardiopulmonary function indices and histological observations in chickens. The results show heat-stress induced a decrease (P < 0.05) in body weight and an increase in body temperature, which was reversed after MT intervention. Treatment with MT inhibited (P < 0.05) the secretion of pro-inflammatory factors interleukin-1ß, interleukin-6, tumor necrosis factor α, serum heat shock protein 70, corticosterone, and elevated (P < 0.05) the levels of biochemical factors total protein, albumin, globulin, and increased (P < 0.05) the activities of antioxidant enzymes superoxide dismutase, glutathione peroxidase and catalase in chicken serum caused by heat stress, and the best effect was observed with the medium dose of MT. The heat-stress caused cardiac atrophy and pulmonary congestion, decreased (P < 0.05) the cardiac function indices creatine kinase isoenzyme, cardiac troponin I, angiotensin receptor I, creatine kinase and lung function indices myeloperoxidase, angiotensin-II, heat shock factor I, and increased (P < 0.05) the lung vascular endothelial growth factor II. Sections of the heart and lungs after administration of MT were observed to be more complete with more normal tissue indices. At the same time, compared with heat stress, heart and lung function indices of grade chickens after MT administration were significantly (P < 0.05)reduced and tended to normal levels, and the best effect was observed in the medium-dose MT. In conclusion, heat stress can cause pathophysiological damage in chickens, and 1 mg/kg/d of exogenous melatonin can attenuate this adverse effect.


Assuntos
Galinhas , Transtornos de Estresse por Calor , Resposta ao Choque Térmico , Melatonina , Animais , Melatonina/farmacologia , Melatonina/administração & dosagem , Resposta ao Choque Térmico/efeitos dos fármacos , Transtornos de Estresse por Calor/tratamento farmacológico , Transtornos de Estresse por Calor/veterinária , Antioxidantes , Citocinas/metabolismo , Citocinas/sangue , Masculino , Doenças das Aves Domésticas/tratamento farmacológico
5.
Hum Mol Genet ; 30(3-4): 277-293, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33355648

RESUMO

Ankylosing spondylitis (AS) is a rheumatic disease with pathological osteogenesis that causes bony ankylosis and even deformity over time. Mesenchymal stem cells (MSCs) are multipotent stem cells that are the main source of osteoblasts. We previously demonstrated that enhanced osteogenic differentiation of MSCs from AS patients (ASMSCs) is related to pathological osteogenesis in AS. However, the more concrete mechanism needs further exploration. Super enhancers (SEs) are dense clusters of stitched enhancers that control cell identity determination and disease development. Single-nucleotide polymorphisms (SNPs) regulate the formation and interaction of SEs and denote genes accounting for AS susceptibility. Via integrative analysis of multiomic data, including histone 3 lysine 27 acetylation (H3K27ac), chromatin immunoprecipitation sequencing (ChIP-seq), SNPs and RNA sequencing (RNA-seq) data, we discovered a transcription network mediated by AS SNP-adjacent SEs (SASEs) in ASMSCs and identified key genes, such as Toll-like receptor 4 (TLR4), interleukin 18 receptor 1 (IL18R1), insulin-like growth factor binding protein 4 (IGFBP4), transportin 1 (TNPO1) and proprotein convertase subtilisin/kexin type 5 (PCSK5), which are pivotal in osteogenesis and AS pathogenesis. The SASE-regulated network modulates the enhanced osteogenic differentiation of ASMSCs by synergistically activating the PI3K-Akt, NF-kappaB and Hippo signaling pathways. Our results emphasize the crucial role of the SASE-regulated network in pathological osteogenesis in AS, and the preferential inhibition of ASMSC osteogenic differentiation by JQ1 indicates that SEs may be attractive targets in future treatment for new bone formation in AS.


Assuntos
Redes Reguladoras de Genes , Células-Tronco Mesenquimais/metabolismo , Osteogênese/genética , Transdução de Sinais , Espondilite Anquilosante/genética , Diferenciação Celular , Células Cultivadas , Sequenciamento de Cromatina por Imunoprecipitação , Humanos , Proteína 4 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Subunidade alfa de Receptor de Interleucina-18/genética , Células-Tronco Mesenquimais/fisiologia , Polimorfismo de Nucleotídeo Único , Pró-Proteína Convertase 5/genética , Análise de Sequência de RNA , Espondilite Anquilosante/fisiopatologia , Receptor 4 Toll-Like/genética , beta Carioferinas/genética
6.
BMC Plant Biol ; 23(1): 189, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37038109

RESUMO

Dendrobium orchids have multiple photosynthetic pathways, which can be used as a model system for studying the evolution of crassulacean acid metabolism (CAM). In this study, based on the results of the net photosynthetic rates (Pn), we classified Dendrobium species into three photosynthetic pathways, then employed and compared their chloroplast genomes. The Dendrobium chloroplast genomes have typical quartile structures, ranging from 150,841-153,038 bp. The apparent differences in GC content, sequence variability, and IR junctions of SSC/IRB junctions (JSBs) were measured within chloroplast genomes among different photosynthetic pathways. The phylogenetic analysis has revealed multiple independent CAM origins among the selected Dendrobium species. After counting insertions and deletions (InDels), we found that the occurrence rates and distribution densities among different photosynthetic pathways were inconsistent. Moreover, the evolution patterns of chloroplast genes in Dendrobium among three photosynthetic pathways were also diversified. Considering the diversified genome structure variations and the evolution patterns of protein-coding genes among Dendrobium species, we proposed that the evolution of the chloroplast genomes was disproportional among different photosynthetic pathways. Furthermore, climatic correlation revealed that temperature and precipitation have influenced the distribution among different photosynthetic pathways and promoted the foundation of CAM pathway in Dendrobium orchids. Based on our study, we provided not only new insights into the CAM evolution of Dendrobium but also provided beneficial genetic data resources for the further systematical study of Dendrobium.


Assuntos
Dendrobium , Genoma de Cloroplastos , Filogenia , Dendrobium/genética , Mudança Climática , Cloroplastos/genética , Evolução Molecular
7.
BMC Plant Biol ; 23(1): 586, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37993773

RESUMO

BACKGROUND: Mitochondrial genomes are essential for deciphering the unique evolutionary history of seed plants. However, the rules of their extreme variation in genomic size, multi-chromosomal structure, and foreign sequences remain unresolved in most plant lineages, which further hindered the application of mitogenomes in phylogenetic analyses. RESULTS: Here, we took Dendrobium (Orchidaceae) which shows the great divergence of morphology and difficulty in species taxonomy as the study focus. We first de novo assembled two complete mitogenomes of Dendrobium wilsonii and Dendrobium henanense that were 763,005 bp and 807,551 bp long with multichromosomal structures. To understand the evolution of Dendrobium mitogenomes, we compared them with those of four other orchid species. The results showed great variations of repetitive and chloroplast-derived sequences in Dendrobium mitogenomes. Moreover, the intergenic content of Dendrobium mitogenomes has undergone expansion during evolution. We also newly sequenced mitogenomes of 26 Dendrobium species and reconstructed phylogenetic relationships of Dendrobium based on genomic mitochondrial and plastid data. The results indicated that the existence of chloroplast-derived sequences made the mitochondrial phylogeny display partial characteristics of the plastid phylogeny. Additionally, the mitochondrial phylogeny provided new insights into the phylogenetic relationships of Dendrobium species. CONCLUSIONS: Our study revealed the evolution of Dendrobium mitogenomes and the potential of mitogenomes in deciphering phylogenetic relationships at low taxonomic levels.


Assuntos
Dendrobium , Genoma Mitocondrial , Orchidaceae , Filogenia , Orchidaceae/genética , Dendrobium/genética , Genoma Mitocondrial/genética , Genômica/métodos , Sequência de Bases
8.
Opt Express ; 31(2): 3143-3152, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785312

RESUMO

We propose polarization-sensitive second-harmonic generation microscopy based on off-axis interferometry (OI-PSHG) by recording the complex field of a wide-field second-harmonic generation (SHG) image and performing polarization measurements. With the ability to record the SHG signals associated with different positions simultaneously, the proposed method exhibits a higher imaging frame rate than raster scanning-based SHG microscopy. The molecular orientation (in terms of their symmetric axis) of tendon collagen fibrils and myosin in muscle is resolved in three dimensions from a subset of polarization-resolved SHG holograms. With the present configuration, it takes approximately 0.01 s to acquire an image with 128 × 128 pixels, which is mainly limited by the excitation power density for wide-field illumination. For the same data throughput using pixel-by-pixel scanning, 0.16-s-long acquisition is required, with the pixel dwell time of 10 µs. Offering the ability to perform wide-field imaging and polarization measurements, the present work lays the foundation for fast SHG microscopy using complex deconvolution and harmonic tomography.

9.
Cerebellum ; 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993636

RESUMO

Ataxia-ocular apraxia 2 (AOA2) is a rare neurodegenerative autosomal recessive disorder with no effective treatment. In this study, we present the case of a patient diagnosed with AOA2, who experienced walking instability and uncoordinated movement. The patient underwent transcranial alternating current stimulation (tACS) treatment for 4 weeks with follow-up after 1 month. The effectiveness of the treatment was evaluated using the International Cooperative Ataxia Rating Scale (ICARS), the Scale for the Assessment and Rating of Ataxia (SARA), the 9-Hole Peg Test (9HPT), and functional near-infrared spectroscopy (fNIRS). Following treatment, the patient's ataxia symptoms showed significant improvement and continued to be alleviated during the follow-up period, suggesting a lasting effect of tACS treatment. Our findings from this case study provide compelling evidence for the potential of tACS as a treatment option for AOA2.

10.
J Nanobiotechnology ; 21(1): 280, 2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37598147

RESUMO

Sustained inflammatory invasion leads to joint damage and progressive disability in several autoimmune rheumatic diseases. In recent decades, targeting M1 macrophage polarization has been suggested as a promising therapeutic strategy for autoimmune arthritis. P300/CBP-associated factor (PCAF) is a histone acetyltransferase (HAT) that exhibits a strong positive relationship with the proinflammatory microenvironment. However, whether PCAF mediates M1 macrophage polarization remains poorly studied, and whether targeting PCAF can protect against autoimmune arthritis in vivo remains unclear. Commonly used drugs can cause serious side effects in patients because of their extensive and nonspecific distribution in the human body. One strategy for overcoming this challenge is to develop drug nanocarriers that target the drug to desirable regions and reduce the fraction of drug that reaches undesirable targets. In this study, we demonstrated that PCAF inhibition could effectively inhibit M1 polarization and alleviate arthritis in mice with collagen-induced arthritis (CIA) via synergistic NF-κB and H3K9Ac blockade. We further designed dextran sulfate (DS)-based nanoparticles (DSNPs) carrying garcinol (a PCAF inhibitor) to specifically target M1 macrophages in inflamed joints of the CIA mouse model via SR-A-SR-A ligand interactions. Compared to free garcinol, garcinol-loaded DSNPs selectively targeted M1 macrophages in inflamed joints and significantly improved therapeutic efficacy in vivo. In summary, our study indicates that targeted PCAF inhibition with nanoparticles might be a promising strategy for treating autoimmune arthritis via M1 macrophage polarization inhibition.


Assuntos
Artrite , NF-kappa B , Humanos , Animais , Camundongos , Terpenos , Macrófagos
11.
Planta Med ; 89(15): 1468-1482, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37541437

RESUMO

Boswellia is a traditional medicine for bruises and injuries. Its main active ingredient, acetyl-11-keto-beta-boswellic acid, has antioxidant and antiapoptotic effects. In this experiment, we used Sprague-Dawley rats to make a sciatic nerve injury model to detect the transcription factor NF-E2-related factor 2/heme oxygenase 1 signaling pathway and apoptosis, combined with clinical indicators, for testing whether acetyl-11-keto-beta-boswellic acid can reduce oxidative stress and promote sciatic nerve repair. Our results showed that acetyl-11-keto-beta-boswellic acid administration promoted myelin regeneration and functional recovery in the rat sciatic nerve, reduced lipid peroxidation levels, upregulated the expression of various antioxidant enzymes and enhanced enzyme activity, decreased the expression levels of apoptosis-related proteins, and promoted nuclear translocation of the transcription factor NF-E2-related factor 2 protein. In vitro studies revealed that acetyl-11-keto-beta-boswellic acid reduced H2O2-induced reactive oxygen species production, restored mitochondrial membrane potential, upregulated the expression of various antioxidant enzymes, and downregulated apoptosis-related indicators in Schwann cells, and these therapeutic effects of acetyl-11-keto-beta-boswellic acid were reversed after ML385 treatment in Schwann cells. In summary, acetyl-11-keto-beta-boswellic acid alleviates oxidative stress and apoptosis caused by sciatic nerve injury in rats by activating the transcription factor NF-E2-related factor 2/heme oxygenase 1 signaling pathway, promotes the recovery of sciatic nerve function in rats, and is a promising therapeutic agent to promote sciatic nerve repair by alleviating excessive oxidative stress.


Assuntos
Heme Oxigenase-1 , Triterpenos , Ratos , Animais , Heme Oxigenase-1/metabolismo , Heme Oxigenase-1/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Ratos Sprague-Dawley , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo , Transdução de Sinais , Triterpenos/farmacologia , Triterpenos/uso terapêutico , Triterpenos/metabolismo , Nervo Isquiático/metabolismo , Células de Schwann/metabolismo
12.
Int J Mol Sci ; 25(1)2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38203528

RESUMO

The primary aim of this study is to delve into the potential of Acetyl-11-keto-ß-boswellic acid (AKBA) in ameliorating neuronal damage induced by acute spinal cord injury, as well as to unravel the intricate underlying mechanisms. A cohort of 40 Sprague-Dawley rats was meticulously categorized into four groups. Following a seven-day oral administration of AKBA, damaged spinal cord samples were meticulously procured for Nissl staining and electron microscopy to assess neuronal demise. Employing ELISA, immunofluorescence, Western blot (WB), and quantitative polymerase chain reaction (qPCR), the modulatory effects of AKBA within the context of spinal cord injury were comprehensively evaluated. Furthermore, employing an ex vivo extraction of spinal cord neurons, an ATP + LPS-induced pyroptotic injury model was established. The model was subsequently subjected to Nrf2 inhibition, followed by a battery of assessments involving ELISA, DCFH-DA staining, flow cytometry, immunofluorescence, and WB to decipher the effects of AKBA on the spinal cord neuron pyroptosis model. By engaging the Nrf2-ROS-NLRP3 pathway, AKBA exerted a repressive influence on the expression of the pyroptotic initiator protein Caspase-1, thereby mitigating the release of GSDMD and alleviating pyroptosis. Additionally, AKBA demonstrated the ability to attenuate the release of IL-18 and IL-1ß, curbing neuronal loss and expediting the restorative processes within the context of spinal cord injury. Our study elucidates that AKBA can reduce spinal cord neuronal apoptosis, providing a basis for the development of AKBA as a clinical treatment for spinal cord injury.


Assuntos
Piroptose , Traumatismos da Medula Espinal , Triterpenos , Humanos , Ratos , Animais , Fator 2 Relacionado a NF-E2/genética , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/tratamento farmacológico
13.
Toxicol Mech Methods ; 33(2): 131-140, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35850572

RESUMO

Aristolochic acid is internationally recognized as a carcinogen. It has been shown that the main toxic mechanism of aristolochic acid on the liver and kidney is the induction of ROS-induced oxidative stress damage. To investigate whether proanthocyanidins (GSPE), a natural antioxidant product from grape seed extract, could antagonize AA-I-induced liver injury. Thirty-two SD rats were selected and divided into aristolochic acid exposure group (AA-I), normal control group, GSPE group and GSPE intervention group. The protective effects of GSPE on AA-I liver injury were evaluated by examining the body weight, liver index, liver function and liver pathological sections of rats. The results of body weight, liver index, liver function and liver pathological sections of rats showed that GSPE had antagonistic effects on AA-I-induced liver injury. antioxidant enzyme activity in the GSPE intervention group was significantly higher than that in the aristolochic acid group, apoptotic cells were significantly lower than that in the aristolochic acid group, protein and mRNA expression of PI3K-AKT and BCL-2 were significantly higher than that in the aristolochic acid group, BAX, The protein and mRNA expression of BAX, CASPAES-3, CASPAES-9 were significantly lower than those of the aristolochic acid group. GSPE can antagonize aristolochic acid-induced hepatotoxicity, and its mechanism of action is to antagonize aristolochic acid I-induced liver injury by inhibiting PI3K-AKT pathway-mediated hepatocyte apoptosis.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Extrato de Sementes de Uva , Proantocianidinas , Animais , Ratos , Antioxidantes/farmacologia , Proteína X Associada a bcl-2/metabolismo , Extrato de Sementes de Uva/farmacologia , Estresse Oxidativo , Fosfatidilinositol 3-Quinases/metabolismo , Proantocianidinas/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , RNA Mensageiro/metabolismo
14.
BMC Plant Biol ; 22(1): 201, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35439926

RESUMO

BACKGROUND: Because chloroplast (cp) genome has more conserved structures than nuclear genome and mitochondrial genome, it is a useful tool in estimating the phylogenetic relationships of plants. With a series of researches for cp genomes, there have been comprehensive understandings about the cp genome features. The genus Bulbophyllum widely distributed in Asia, South America, Australia and other places. Therefore, it is an excellent type genus for studying the effects of geographic isolation. RESULTS: In this study, the cp genomes of nine Bulbophyllum orchids were newly sequenced and assembled using the next-generation sequencing technology. Based on 19 Asian (AN) and eight South American (SA) Bulbophyllum orchids, the cp genome features of AN clade and SA clade were compared. Comparative analysis showed that there were considerable differences in overall cp genome features between two clades in three aspects, including basic cp genome features, SSC/IRB junctions (JSBs) and mutational hotspots. The phylogenetic analysis and divergence time estimation results showed that the AN clade has diverged from the SA clade in the late Oligocene (21.50-30.12 mya). After estimating the occurrence rates of the insertions and deletions (InDels), we found that the change trends of cp genome structures between two clades were different under geographic isolation. Finally, we compared selective pressures on cp genes and found that long-term geographic isolation made AN and SA Bulbophyllum cp genes evolved variably. CONCLUSION: The results revealed that the overall structural characteristics of Bulbophyllum cp genomes diverged during the long-term geographic isolation, and the crassulacean acid metabolism (CAM) pathway may play an important role in the Bulbophyllum species evolution.


Assuntos
Genoma de Cloroplastos , Orchidaceae , Ásia , Austrália , Genoma de Cloroplastos/genética , Orchidaceae/genética , Filogenia
15.
Opt Express ; 30(25): 45724-45737, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36522971

RESUMO

Computed tomography (CT) allows for high lateral and axial resolution imaging of the endogenous structure of matter thanks to its large spatial frequency support and has been realized in X-ray and linear optical domain known as optical diffraction tomography (ODT). Here, we present the theoretical basis and experimental considerations for ODT of second-order nonlinear structures in weak scattering media. We have derived the relation between second harmonic wave and the anisotropic nonlinear tensor in spatial frequency domain under first-order Born approximation. Our results show that, under a plane wave illumination, the two dimensional (2D) spatial spectra of generated second harmonic complex field relates to the inverse lattice of nonlinear structure on Ewald sphere shells. The centers of the Ewald spheres are determined by 2 times wavevector of the incident fundamental wave and the radii are determined by the modulus of the second harmonic wavevector. More importantly, it shows that the 2D spatial spectra is a superposition of the Ewald spheres of different components of the anisotropic nonlinear tensor. We propose to solve the inverse problem by controlling the polarizations of the fundamental and second harmonic signal. We tested the feasibility of the proposed method using a numerical phantom and make some discussions on practical implementations, including angular scanning schemes, polarization detection and illumination profile for optimizing reconstruction region. Possessing high resolution, wide-field imaging and polarization-sensitive property, we believe that the proposed scheme would have important applications in nonlinear microscopy.

16.
J Biomed Sci ; 29(1): 73, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36127734

RESUMO

BACKGROUND: Mesenchymal stem cells (MSCs) exhibit two bidirectional immunomodulatory abilities: proinflammatory and anti-inflammatory regulatory effects. Long noncoding RNAs (lncRNAs) have important functions in the immune system. Previously, we performed high-throughput sequencing comparing lncRNA expression profiles between MSCs cocultured with or without CD14+ monocytes and screened out a new lncRNA termed lncRNA MCP1 regulatory factor (MRF). However, the mechanism of MRF in MSCs is still unknown. METHODS: MRF expression was quantified via qRT-PCR. RNA interference and lentiviruses were used to regulate MRF expression. The immunomodulatory effects of MSCs on monocytes were evaluated via monocyte migration and macrophage polarization assays. RNA pull-down and mass spectrometry were utilized to identify downstream factors of MRF. A dual-luciferase reporter assay was applied to analyze the transcription factors regulating MRF. qRT-PCR, western blotting and ELISAs were used to assess MCP1 expression. A human monocyte adoptive transfer mouse model was applied to verify the function of MRF in vivo. RESULTS: MRF was upregulated in MSCs during coculture with CD14+ monocytes. MRF increased monocyte recruitment by upregulating the expression of monocyte chemotactic protein (MCP1). Knockdown of MRF enhanced the regulatory effect of MSCs on restraining M1 polarization and facilitating M2 polarization. Mechanistically, MRF bound to the downstream protein heterogeneous nuclear ribonucleoprotein D (HNRNPD) to upregulate MCP1 expression, and the transcription factor interferon regulatory factor 1 (IRF1) activated MRF transcription early during coculture. The human monocyte adoptive transfer model showed that MRF downregulation in MSCs inhibited monocyte chemotaxis and enhanced the effects of MSCs to inhibit M1 macrophage polarization and promote M2 polarization in vivo. CONCLUSION: We identified the new lncRNA MRF, which exhibits proinflammatory characteristics. MRF regulates the ability of MSCs to accelerate monocyte recruitment and modulate macrophage polarization through the HNRNPD-MCP1 axis and initiates the proinflammatory regulatory process in MSCs, suggesting that MRF is a potential target to improve the clinical effect of MSC-based therapy or correct MSC-related immunomodulatory dysfunction under pathological conditions.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas Grupo D , Células-Tronco Mesenquimais , RNA Longo não Codificante , Animais , Anti-Inflamatórios/farmacologia , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/farmacologia , Humanos , Fator Regulador 1 de Interferon/metabolismo , Fator Regulador 1 de Interferon/farmacologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Proteínas Quimioatraentes de Monócitos/metabolismo , Proteínas Quimioatraentes de Monócitos/farmacologia , Monócitos/metabolismo , RNA Longo não Codificante/metabolismo
17.
Can J Physiol Pharmacol ; 100(6): 562-572, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35413215

RESUMO

Mecobalamin is commonly used in the adjuvant intervention of various peripheral nerve injuries. Actin cytoskeleton plays a role in the regeneration of myelin and axon. Therefore, the purpose of this study was to explore the possibility of mecobalamin regulating actin cytoskeleton in repairing nerve injury. In this study, a crush injury on the right sciatic nerve of two groups of rats (12 in each group) was established. The control group was only given normal saline (i.g.), and the intervention group was given mecobalamin 1 mg/kg (i.g.). The rats were sacrificed on 28th day and the injured nerves were collected for proteomics. The result shows that regulation of actin cytoskeleton pathway changed significantly. The expression of protein Vav1 was verified by Western blot and immunofluorescence. In the intervention group, the nerve fiber structure was complete, the axons were dense and symmetrical, and the myelin sheath was compact and uniform in thickness. The positive rate of myelin basic protein and ßⅢ-tubulin was higher than that in the control group. The findings of the study show that mecobalamin regulates the actin cytoskeleton in the repair of nerve damage and upregulates Vav1 in the regulation of actin cytoskeleton pathway.


Assuntos
Traumatismos dos Nervos Periféricos , Proteômica , Animais , Axônios/metabolismo , Traumatismos dos Nervos Periféricos/tratamento farmacológico , Proteínas Proto-Oncogênicas c-vav/metabolismo , Ratos , Nervo Isquiático/metabolismo , Vitamina B 12/análogos & derivados
18.
Int J Mol Sci ; 23(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36555556

RESUMO

The existing studies by our team demonstrated the pro-recovery effect of 3-Acetyl-11-keto-beta-boswellic acid (AKBA) on a sciatic nerve injury. To further investigate the role of AKBA in peripheral nerve injury repair, The TMT quantitative proteomics technique was used to obtain differentially significant proteins in a Sham group, Model group, and AKBA group. After that, three time points (5, 14, and 28 d) and four groups (Sham + AKBA, Sham, Model, and AKBA) were set up, and immunoblotting, immunofluorescence, and cellular assays were applied to investigate the expression of CDC42, Rac1, RhoA, and Rictor in the sciatic nerve at different time points for each group in more depth. The results showed that AKBA enriched the cellular components of the myelin sheath and axon regeneration after a sciatic nerve injury and that AKBA upregulated CDC42 and Rac1 and downregulated RhoA expression 5 d after a sciatic nerve injury, promoting axon regeneration and improving the repair of a sciatic nerve injury in rats. Rictor is regulated by AKBA and upregulated in PC12 cells after AKBA action. Our findings provide a new basis for AKBA treatment of a peripheral nerve injury.


Assuntos
Traumatismos dos Nervos Periféricos , Neuropatia Ciática , Animais , Ratos , Axônios , Regeneração Nervosa/fisiologia , Proteína Companheira de mTOR Insensível à Rapamicina , Nervo Isquiático/lesões , Neuropatia Ciática/tratamento farmacológico
19.
Toxicol Mech Methods ; 32(7): 510-517, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35253580

RESUMO

As a pesticide extracted from plants, rotenone is widely used to control plant pests. In order to explore the safety of rotenone in the environment, we took 60 healthy male SD rats and randomly divided them into rotenone low-dose group, rotenone medium-dose group, rotenone high-dose group, dimethyl sulfoxide group (DMSO), and control group. After 28 days of oral administration, the rat liver tissue ultrastructure, liver function, oxidative stress indexs, mitochondrial function, and apoptosis-related factors were tested to evaluate the hepatotoxicity and toxicological mechanism of rotenone. The results showed that rotenone significantly increased the hepatic index of rats and the activity of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum. Rotenone can reduce the number of endoplasmic reticulum of hepatocyte, concentrate chromatin and make the hepatocyte nuclears irregular. Rotenone weakened the ATP synthesis ability in mitochondria, decreased the activity of ATP enzyme in mitochondria, and increased the mitochondrial membrane potential in the high-dose group. And it induced oxidative stress damage to the mitochondria of rat liver cells. Rotenone can upregulate the expression of pro-apoptotic factors and downregulate the expression of anti-apoptotic factors. These results indicate that oral rotenone in rats induced hepatotoxicity in a dose-dependent manner. The mechanism of rotenone poisoning is that oxidative stress damages organelles of hepatocyte such as mitochondria and endoplasmic reticulum, resulting in their function being weakened or lost, leading to hepatocyte apoptosis.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Rotenona , Trifosfato de Adenosina/metabolismo , Animais , Apoptose , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Mitocôndrias/metabolismo , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Rotenona/toxicidade
20.
Opt Lett ; 46(12): 2803-2806, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34129544

RESUMO

Measuring the complex field of ultrashort pulse lasers plays a fundamental role in light wavefront manipulation and nonlinear phenomena investigation; yet, it still constitutes a challenge for both full-field and high-resolution characterization due to the short coherent length. We proposed and implemented an off-axis interference system with a delay-line sweeping technique to overcome the fringe contrast degradation caused by the envelope mismatch between interfering pulses, resulting in an increased effective analysis area. The effectiveness of the proposed method was first demonstrated by measuring a complex field generated by a phase-only spatial light modulator, where a four-pixel binning technique was adopted for both amplitude and phase modulation; then it was used for the measurement of the second harmonic generation signal of a urea crystal sample. The experimental results show that the proposed method is capable of measuring complex fields having fine features within the full field. The proposed technique can be applied for strongly scattering medium refocusing and adaptive optics, where measuring the complex field of ultrashort pulse lasers is essential.

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