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1.
Lupus ; 33(8): 828-839, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38662532

RESUMO

BACKGROUND: The current prediction models for the risk of infection during immunosuppressive treatment for lupus nephritis (LN) lack a prediction time window and have poor pertinence. This study aimed to develop a risk stratification to predict infection during immunosuppressive therapy in patients with LN. METHODS: This retrospective nested case-control study collected patients with LN treated with immunosuppressive therapy between 2014 and 2022 in the Nephrology ward in Huashan Hospital affiliated to Fudan University and Huashan Hospital Baoshan Branch. Cases were defined as patients who experienced infection during the follow-up period; patients were eligible as controls if they did not have infection during the follow-up period. RESULTS: There were 53 patients with infection by CTCAE V5.0 grade ≥2. According to the 1:3 nested matching, the 53 patients with infection were matched with 159 controls. In the multivariable logistic regression model, the change rate of fibrinogen (OR = 0.97, 95% CI: 0.94-0.99, p = 0.008), leukopenia (OR = 8.68, 95% CI: 1.16-301.72, p = 0.039), and reduced albumin (OR = 6.25, 95% CI: 1.38-28.24, p = 0.017) were independently associated with infection. The AUC of the ROC curve in the validation set of the multivariable logistic regression model in the internal random sampling was 0.864. The scores range from -2 to 10. The infection risk stratification ranges from 2.8% at score -2 to 97.5% at score 10. CONCLUSION: A risk stratification was built to predict the risk of infection in patients with LN undergoing immunosuppressive therapy.


Assuntos
Imunossupressores , Nefrite Lúpica , Humanos , Nefrite Lúpica/tratamento farmacológico , Feminino , Masculino , Estudos Retrospectivos , Adulto , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Estudos de Casos e Controles , Medição de Risco , Pessoa de Meia-Idade , Fatores de Risco , Infecções/epidemiologia , Infecções/etiologia , Modelos Logísticos , Curva ROC , Adulto Jovem , Leucopenia/induzido quimicamente , Leucopenia/epidemiologia
2.
Nephrol Dial Transplant ; 39(11): 1876-1889, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38587855

RESUMO

BACKGROUND: Inflammation is crucial in the development of acute kidney injury (AKI) and subsequent chronic kidney disease (CKD) following renal ischaemia-reperfusion (IR) injury. Gut microbiota metabolites trigger inflammation and affect IR-induced renal damage. Yet the driving factors and mechanisms are unclear. Trimethylamine N-oxide (TMAO), a gut-derived choline metabolite, is a strong pro-inflammatory factor that increases in patients with AKI and CKD. We hypothesized that TMAO can promote renal injury caused by IR. METHODS: Mice subjected to unilateral renal IR to induce AKI and CKD were fed a high-choline diet to observe the effects of TMAO on kidney inflammation, fibrosis and macrophage dynamics. RESULTS: A choline-rich diet altered the gut microbiota and elevated TMAO levels, exacerbating IR-induced AKI and subsequent CKD. Single-cell analysis identified a distinct subset of CCR2+ macrophages derived from monocytes as key responders to TMAO, intensifying immune cell interactions and worsening renal injury. TMAO promoted sustained CCR2 expression after IR, increasing macrophage infiltration. CCR2 deletion and antagonist RS-102895 improved TMAO-induced inflammation and fibrosis and alleviated renal injury induced by IR. CONCLUSIONS: Our study provides valuable insights into the link between TMAO and IR-induced renal inflammation and fibrosis, emphasizing the critical role of TMAO-mediated macrophage infiltration via CCR2 as a key therapeutic target in the acute and chronic phases after IR.


Assuntos
Injúria Renal Aguda , Microbioma Gastrointestinal , Macrófagos , Metilaminas , Receptores CCR2 , Animais , Metilaminas/metabolismo , Camundongos , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Receptores CCR2/metabolismo , Receptores CCR2/genética , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/etiologia , Inflamação/metabolismo , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/patologia , Insuficiência Renal Crônica/etiologia
3.
Ren Fail ; 46(1): 2296612, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38178566

RESUMO

Intradialytic hypotension (IDH) is a common complication of hemodialysis (HD), but there is no consensus on its definition. In 2015, Flythe proposed a definition of IDH (Definition 1 in this study): nadir systolic blood pressure (SBP) <90 mmHg during hemodialysis for patients with pre-dialysis SBP <159 mmHg, and nadir SBP <100 mmHg during hemodialysis for patients with pre-dialysis SBP ≥160 mmHg. This prospective observational cohort study investigated the association of frequent IDH based on Definition 1 with clinical outcomes and compared Definition 1 with a commonly used definition (nadir SBP <90 mmHg during hemodialysis, Definition 2). The incidence of IDH was observed over a 3-month exposure assessment period. Patients with IDH events ≥30% were classified as 'frequent IDH'; the others were 'infrequent IDH'. All-cause mortality, cardiovascular mortality, and all-cause hospitalization events were followed up for 36 months. This study enrolled 163 HD patients. The incidence of IDH was 11.1% according to Definition 1 and 10.5% according to Definition 2. The Kaplan-Meier curves showed that frequent IDH patients had higher risks of all-cause mortality (p = 0.009, Definition 1; p = 0.002, Definition 2) and cardiovascular mortality (p = 0.021, Definition 1). Multivariable Cox regression analysis indicated that frequent IDH was independently associated with a higher risk of all-cause mortality (Model 1: HR = 2.553, 95%CI 1.334-4.886, p = 0.005; Model 2: HR = 2.406, 95%CI 1.253-4.621, p = 0.008). In conclusion, HD patients classified as frequent IDH are at a greater risk of all-cause mortality. This highlights the significance of acknowledging and proactively managing frequent IDH within the HD patients.


Assuntos
Hipotensão , Falência Renal Crônica , Humanos , Estudos Prospectivos , Falência Renal Crônica/complicações , Diálise Renal/efeitos adversos , Hipotensão/epidemiologia , Hipotensão/etiologia , Pressão Sanguínea
7.
J Nanobiotechnology ; 21(1): 98, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36941678

RESUMO

BACKGROUND: Bone regeneration is a complex procedure that involves an interaction between osteogenesis and inflammation. Macrophages in the microenvironment are instrumental in bone metabolism. Amount evidence have revealed that exosomes transmitting lncRNA is crucial nanocarriers for cellular interactions in various biotic procedures, especially, osteogenesis. However, the underlying mechanisms of the regulatory relationship between the exosomes and macrophages are awaiting clarification. In the present time study, we aimed to explore the roles of human umbilical vein endothelial cells (HUVECs)-derived exosomes carrying nuclear enrichment enriched transcript 1 (NEAT1) in the osteogenesis mediated by M2 polarized macrophages and elucidate the underlying mechanisms. RESULTS: We demonstrated HUVECs-derived exosomes expressing NEAT1 significantly enhanced M2 polarization and attenuated LPS-induced inflammation in vitro. Besides, the conditioned medium from macrophages induced by the exosomes indirectly facilitated the migration and osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). Mechanically, Exos carrying NEAT1 decreased remarkably both expression of dead-box helicase 3X-linked (DDX3X) and nod-like receptor protein 3 (NLRP3). The level of NLRP3 protein increased significantly after RAW264.7 cells transfected with DDX3X overexpression plasmid. Additionally, the knockdown of NEAT1 in exosomes partially counteracted the aforementioned effect of Exos. The results of air pouch rat model demonstrated that HUVECs-derived exosomes increased anti-inflammatory cytokines (IL-10) and decreased pro-inflammatory cytokines (IL-1ß and IL-6) significantly in vivo, contributing to amelioration of LPS-induced inflammation. Afterwards, we further confirmed that the HUVECs-derived exosomes encapsulated in alginate/gelatin methacrylate (GelMA) interpenetrating polymer network (IPN) hydrogels could promote the bone regeneration, facilitate the angiogenesis, increase the infiltration of M2 polarized macrophages as well as decrease NLRP3 expression in the rat calvarial defect model. CONCLUSIONS: HUVECs-derived exosomes enable transmitting NEAT1 to alleviate inflammation by inducing M2 polarization of macrophages through DDX3X/NLRP3 regulatory axis, which finally contributes to osteogenesis with the aid of alginate/GelMA IPN hydrogels in vivo. Thus, our study provides insights in bone healing with the aid of HUVECs-derived exosomes-encapsulated composite hydrogels, which exhibited potential towards the use of bone tissue engineering in the foreseeable future.


Assuntos
Regeneração Óssea , Macrófagos , Osteogênese , RNA Longo não Codificante , Animais , Humanos , Ratos , Citocinas/metabolismo , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Hidrogéis/farmacologia , Inflamação/metabolismo , Lipopolissacarídeos , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , RNA Longo não Codificante/genética
8.
BMC Nephrol ; 24(1): 209, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37452301

RESUMO

BACKGROUND: Intradialytic hypotension (IDH) is frequently accompanied by symptoms of nausea, dizziness, fatigue, muscle spasm, and arrhythmia, which can adversely impact the daily lives of patients who undergo hemodialysis and may lead to decreased quality of life (QoL). This study employed the KDQOL™-36 scale to evaluate the impact of frequent IDH, based on the definition determined by predialysis blood pressure (BP) and nadir systolic blood pressure (SBP) thresholds, on the QoL of patients. METHODS: This is a single center retrospective cohort study involving 160 hemodialysis patients. We enrolled adult patients with uremia who received routine hemodialysis (4 h/time, 3 times/week) from October 1, 2019, to September 30, 2021. Frequent IDH was defined as an absolute nadir SBP < 90 mmHg occurring in no less than 30% of hemodialysis sessions when predialysis SBP < 159 mmHg (or < 100 mmHg when predialysis BP ≥ 160 mmHg).The differences between patients with and without frequent IDH were compared using the independent t test, Kruskal‒Wallis test, or chi-square test. The primary visit was at month 36, and the remaining visits were exploratory outcomes. RESULTS: Compared to patients with infrequent IDH at baseline, those with frequent IDH had significantly lower scores on the symptoms and discomfort of kidney disease dimension at all follow-up points (P < 0.05). The symptoms and discomfort of kidney disease dimension were worse in patients with frequent IDH. Those with frequent IDH had a significantly poorer QoL regarding the dimensions of symptoms and discomfort of kidney disease and the impact of kidney disease on life. CONCLUSIONS: The findings of the study suggest an association between frequent IDH and QoL dimensions of symptoms and discomfort of kidney disease and the impact of kidney disease on life dimension under the definition of frequent IDH.


Assuntos
Hipotensão , Falência Renal Crônica , Adulto , Humanos , Qualidade de Vida , Falência Renal Crônica/complicações , Estudos Retrospectivos , Diálise Renal/efeitos adversos , Pressão Sanguínea
9.
Sensors (Basel) ; 23(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37430607

RESUMO

To overcome the influence of the daytime skylight background on long-distance optical detection, a new type of shearing interference detection system was proposed to improve the detection performance of the traditional detection system for finding dark objects such as dim stars during the daytime. This article focuses on the basic principle and mathematical model as well as the simulation and experimental research of the new type of shearing interference detection system. The comparison of the detection performance between this new-type detection system and the traditional system is also carried out in this article. The experimental results show that the detection performance of the new type of shearing interference detection system is significantly better than that of the traditional system, and the image signal-to-noise ratio of this new-type system (about 13.2) is much higher than that of the best result of the traditional detection system (about 5.1).

10.
Hum Brain Mapp ; 43(12): 3721-3734, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35466500

RESUMO

The question how the brain distinguishes between information about self and others is of fundamental interest to both philosophy and neuroscience. In this functional magnetic resonance imaging (fMRI) study, we sought to distinguish the neural substrates of representing a full-body movement as one's movement and as someone else's movement. Participants performed a delayed match-to-sample working memory task where a retained full-body movement (displayed using point-light walkers) was arbitrarily labeled as one's own movement or as performed by someone else. By using arbitrary associations we aimed to address a limitation of previous studies, namely that our own movements are more familiar to us than movements of other people. A searchlight multivariate decoding analysis was used to test where information about types of movement and about self-association was coded. Movement specific activation patterns were found in a network of regions also involved in perceptual processing of movement stimuli, however not in early sensory regions. Information about whether a memorized movement was associated with the self or with another person was found to be coded by activity in the left middle frontal gyrus (MFG), left inferior frontal gyrus (IFG), bilateral supplementary motor area, and (at reduced threshold) in the left temporoparietal junction (TPJ). These areas are frequently reported as involved in action understanding (IFG, MFG) and domain-general self/other distinction (TPJ). Finally, in univariate analysis we found that selecting a self-associated movement for retention was related to increased activity in the ventral medial prefrontal cortex.


Assuntos
Memória de Curto Prazo , Córtex Motor , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética/métodos , Memória de Curto Prazo/fisiologia
11.
Nat Methods ; 16(12): 1254-1261, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31780840

RESUMO

Pinpointing subcellular protein localizations from microscopy images is easy to the trained eye, but challenging to automate. Based on the Human Protein Atlas image collection, we held a competition to identify deep learning solutions to solve this task. Challenges included training on highly imbalanced classes and predicting multiple labels per image. Over 3 months, 2,172 teams participated. Despite convergence on popular networks and training techniques, there was considerable variety among the solutions. Participants applied strategies for modifying neural networks and loss functions, augmenting data and using pretrained networks. The winning models far outperformed our previous effort at multi-label classification of protein localization patterns by ~20%. These models can be used as classifiers to annotate new images, feature extractors to measure pattern similarity or pretrained networks for a wide range of biological applications.


Assuntos
Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Microscopia de Fluorescência/métodos , Proteínas/análise , Humanos
12.
Neuroimage ; 226: 117592, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33248258

RESUMO

Previous electrophysiological studies in monkeys and humans suggest that premotor regions are the primary loci for the encoding of perceptual choices during vibrotactile comparisons. However, these studies employed paradigms wherein choices were inextricably linked with the stimulus order and selection of manual movements. It remains largely unknown how vibrotactile choices are represented when they are decoupled from these sensorimotor components of the task. To address this question, we used fMRI-MVPA and a variant of the vibrotactile frequency discrimination task which enabled the isolation of choice-related signals from those related to stimulus order and selection of the manual decision reports. We identified the left contralateral dorsal premotor cortex (PMd) and intraparietal sulcus (IPS) as carrying information about vibrotactile choices. Our finding provides empirical evidence for an involvement of the PMd and IPS in vibrotactile decisions that goes above and beyond the coding of stimulus order and specific action selection. Considering findings from recent studies in animals, we speculate that the premotor region likely serves as a temporary storage site for information necessary for the specification of concrete manual movements, while the IPS might be more directly involved in the computation of choice. Moreover, this finding replicates results from our previous work using an oculomotor variant of the task, with the important difference that the informative premotor cluster identified in the previous work was centered in the bilateral frontal eye fields rather than in the PMd. Evidence from these two studies indicates that categorical choices in human vibrotactile comparisons are represented in a response modality-dependent manner.


Assuntos
Encéfalo/fisiologia , Comportamento de Escolha/fisiologia , Percepção do Tato/fisiologia , Adolescente , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Vibração , Adulto Jovem
13.
J Nanobiotechnology ; 19(1): 209, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34256779

RESUMO

BACKGROUND: The therapeutic potential of exosomes derived from stem cells has attracted increasing interest recently, because they can exert similar paracrine functions of stem cells and overcome the limitations of stem cells transplantation. Exosomes derived from bone mesenchymal stem cells (BMSC-Exos) have been confirmed to promote osteogenesis and angiogenesis. The magnetic nanoparticles (eg. Fe3O4, γ-Fe2O3) combined with a static magnetic field (SMF) has been commonly used to increase wound healing and bone regeneration. Hence, this study aims to evaluate whether exosomes derived from BMSCs preconditioned with a low dose of Fe3O4 nanoparticles with or without the SMF, exert superior pro-osteogenic and pro-angiogenic activities in bone regeneration and the underlying mechanisms involved. METHODS: Two novel types of exosomes derived from preconditioned BMSCs that fabricated by regulating the contents with the stimulation of magnetic nanoparticles and/or a SMF. Then, the new exosomes were isolated by ultracentrifugation and characterized. Afterwards, we conducted in vitro experiments in which we measured osteogenic differentiation, cell proliferation, cell migration, and tube formation, then established an in vivo critical-sized calvarial defect rat model. The miRNA expression profiles were compared among the exosomes to detect the potential mechanism of improving osteogenesis and angiogenesis. At last, the function of exosomal miRNA during bone regeneration was confirmed by utilizing a series of gain- and loss-of-function experiments in vitro. RESULTS: 50 µg/mL Fe3O4 nanoparticles and a 100 mT SMF were chosen as the optimum magnetic conditions to fabricate two new exosomes, named BMSC-Fe3O4-Exos and BMSC-Fe3O4-SMF-Exos. They were both confirmed to enhance osteogenesis and angiogenesis in vitro and in vivo compared with BMSC-Exos, and BMSC-Fe3O4-SMF-Exos had the most marked effect. The promotion effect was found to be related to the highly riched miR-1260a in BMSC-Fe3O4-SMF-Exos. Furthermore, miR-1260a was verified to enhance osteogenesis and angiogenesis through inhibition of HDAC7 and COL4A2, respectively. CONCLUSION: These results suggest that low doses of Fe3O4 nanoparticles combined with a SMF trigger exosomes to exert enhanced osteogenesis and angiogenesis and that targeting of HDAC7 and COL4A2 by exosomal miR-1260a plays a crucial role in this process. This work could provide a new protocol to promote bone regeneration for tissue engineering in the future.


Assuntos
Indutores da Angiogênese/farmacologia , Osso e Ossos/efeitos dos fármacos , Nanopartículas de Magnetita/química , Células-Tronco Mesenquimais/efeitos dos fármacos , MicroRNAs/metabolismo , Osteogênese/efeitos dos fármacos , Animais , Regeneração Óssea/efeitos dos fármacos , Diferenciação Celular , Movimento Celular , Proliferação de Células , Colágeno Tipo IV/metabolismo , Biologia Computacional , Exossomos , Histona Desacetilases/metabolismo , Humanos , Campos Magnéticos , Masculino , Ratos , Cicatrização
14.
Blood Purif ; 50(6): 906-913, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33556944

RESUMO

BACKGROUND: Arteriovenous fistula (AVF) is the most common vascular access for patients undergoing hemodialysis (HD). Neointimal hyperplasia (NIH) might be a potential mechanism of AVF dysfunction. Retinol-binding protein 4 (RBP4) may play an important role in the pathogenesis of NIH. The aim of this study was to investigate whether AVF dysfunction is associated with serum concentrations of RBP4 in HD subjects. METHODS: A cohort of 65 Chinese patients undergoing maintenance HD was recruited between November 2017 and June 2019. The serum concentrations of RBP4 of each patient were measured with the ELISA method. Multivariate logistic regression was used to analyze data on demographics, biochemical parameters, and serum RBP4 level to predict AVF dysfunction events. The cutoff for serum RBP4 level was derived from the highest score obtained on the Youden index. Survival data were analyzed with the Cox proportional hazards regression analysis and Kaplan-Meier method. RESULTS: Higher serum RBP4 level was observed in patients with AVF dysfunction compared to those without AVF dysfunction events (174.3 vs. 168.4 mg/L, p = 0.001). The prevalence of AVF dysfunction events was greatly higher among the high RBP4 group (37.5 vs. 4.88%, p = 0.001). In univariate analysis, serum RBP4 level was statistically significantly associated with the risk of AVF dysfunction (OR = 1.015, 95% CI 1.002-1.030, p = 0.030). In multivariate analysis, each 1.0 mg/L increase in RBP4 level was associated with a 1.023-fold-increased risk of AVF dysfunction (95% CI for OR: 1.002-1.045; p = 0.032). The Kaplan-Meier survival analysis indicated that the incidence of AVF dysfunction events in the high RBP4 group was significantly higher than that in the low-RBP4 group (p = 0.0007). Multivariate Cox regressions demonstrated that RBP4 was an independent risk factor for AVF dysfunction events in HD patients (HR = 1.015, 95% CI 1.001-1.028, p = 0.033). CONCLUSIONS: HD patients with higher serum RBP4 concentrations had a relevant higher incidence of arteriovenous dysfunction events. Serum RBP4 level was an independent risk factor for AVF dysfunction events in HD patients.


Assuntos
Fístula Arteriovenosa/sangue , Diálise Renal , Proteínas Plasmáticas de Ligação ao Retinol/análise , Idoso , Fístula Arteriovenosa/etiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neointima/sangue , Neointima/etiologia , Estudos Prospectivos , Diálise Renal/efeitos adversos , Fatores de Risco
15.
Neuroimage ; 221: 117146, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32659356

RESUMO

Working memory (WM) representations are generally known to be influenced by task demands, but it is not clear whether this extends to the somatosensory domain. One way to investigate the influence of task demands is with categorization paradigms, wherein either a single stimulus or an associated category is maintained in WM. In the somatosensory modality, category representations have been identified in the premotor cortex (PMC) and the intraparietal sulcus (IPS). In this study we used multivariate-pattern-analysis with human fMRI data to investigate whether the WM representations in the PMC, IPS or other regions are influenced by changing task demands. We ensured the task-dependent, categorical WM information was decorrelated from stimulus features by (1) teaching participants arbitrary, non-rule based stimulus groupings and (2) contrasting identical pairs of stimuli across experimental conditions, where either a single stimulus or the associated group was maintained in WM. Importantly, we also decoupled the decision and motor output from the WM representations. With these experimental manipulations, we were able to pinpoint stimulus-specific WM information to the left frontal and parietal cortices and context-dependent, group-specific WM information to the left IPS. By showing that grouped stimuli are represented more similarly in the Group condition than in the Stimulus condition, free from stimulus and motor output confounds, we provide novel evidence for the adaptive nature of somatosensory WM representations in the IPS with changing task-demands.


Assuntos
Adaptação Fisiológica/fisiologia , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Memória de Curto Prazo/fisiologia , Lobo Parietal/fisiologia , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Percepção do Tato/fisiologia , Adulto , Estimulação Elétrica , Feminino , Humanos , Masculino , Lobo Parietal/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Limiar Sensorial/fisiologia , Adulto Jovem
16.
FASEB J ; 33(5): 6069-6081, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30763124

RESUMO

The reconstruction of large bone defects remains a significant challenge for orthopedists. Three-dimensional-printed (3DP) scaffold is considered a promising repair material. Static magnetic field (SMF) treatment is an effective and noninvasive therapeutic method to improve bone regeneration. However, the osteogenic effect of SMF on human bone-derived mesenchymal stem cells (hBMSCs) in 3DP scaffolds, as well as its potential mechanism, are unclear. In this study, the osteogenic effect of SMF on hBMSCs in a 3DP scaffold was investigated in vitro and in vivo. In addition, the potential mechanism for promoting osteogenesis was investigated by proteomic analysis. The results showed that SMF promoted osteogenic differentiation of hBMSCs in vitro. A total of 185 differential proteins were identified under SMF conditions by proteomic analysis. The osteogenic effect might be associated with bone morphogenetic protein-Smad1/5/8-signaling pathway and increased transport of phosphorylated Smad1/5/8 and phosphorylated Smad2/3 to the nucleus by up-regulating Smad4 under SMF conditions. The in vivo experiment showed that bone regeneration and osseointegration was enhanced by SMF in the rat model of bone defect. In conclusion, moderate SMF was a safe and effective method for enhancing osteogenesis in 3DP scaffolds in vitro and in vivo.-He, Y., Yu, L., Liu, J., Li, Y., Wu, Y., Huang, Z., Wu, D., Wang, H., Wu, Z., Qiu, G. Enhanced osteogenic differentiation of human bone-derived mesenchymal stem cells in 3-dimensional printed porous titanium scaffolds by static magnetic field through up-regulating Smad4.


Assuntos
Células-Tronco Mesenquimais/citologia , Osseointegração , Osteogênese , Impressão Tridimensional , Proteína Smad4/genética , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Osso e Ossos/citologia , Células Cultivadas , Humanos , Campos Magnéticos , Masculino , Células-Tronco Mesenquimais/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína Smad4/metabolismo , Titânio/química , Regulação para Cima
17.
Part Fibre Toxicol ; 17(1): 42, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32854727

RESUMO

BACKGROUND: The toxicity of released metallic particles generated in metal-on-metal (MoM) total hip arthroplasty (THA) using cobalt chromium (CoCr) has raised concerns regarding their safety amongst both surgeons and the public. Soft tissue changes such as pseudotumours and metallosis have been widely observed following the use of these implants, which release metallic by-products due to both wear and corrosion. Although activated fibroblasts, the dominant cell type in soft tissues, have been linked to many diseases, the role of synovial fibroblasts in the adverse reactions caused by CoCr implants remains unknown. To investigate the influence of implants manufactured from CoCr, the periprosthetic synovial tissues and synovial fibroblasts from patients with failed MoM THA, undergoing a revision operation, were analysed and compared with samples from patients undergoing a primary hip replacement, in order to elucidate histological and cellular changes. RESULTS: Periprosthetic tissue from patients with MoM implants was characterized by marked fibrotic changes, notably an increase in collagen content from less than 20% to 45-55%, an increase in α-smooth muscle actin positive cells from 4 to 9% as well as immune cells infiltration. Primary cell culture results demonstrated that MoM synovial fibroblasts have a decreased apoptosis rate from 14 to 6% compared to control synovial fibroblasts. In addition, synovial fibroblasts from MoM patients retained higher contractility and increased responsiveness to chemotaxis in matrix contraction. Their mechanical properties at a single cell level increased as observed by a 60% increase in contraction force and higher cell stiffness (3.3 kPa in MoM vs 2.18 kPa in control), as measured by traction force microscopy and atomic force microscopy. Further, fibroblasts from MoM patients promoted immune cell invasion by secreting monocyte chemoattractant protein 1 (MCP-1, CCL2) and induced monocyte differentiation, which could also be associated with excess accumulation of synovial macrophages. CONCLUSION: Synovial fibroblasts exposed in vivo to MoM THA implants that release CoCr wear debris displayed dramatic phenotypic alteration and functional changes. These findings unravelled an unexpected effect of the CoCr alloy and demonstrated an important role of synovial fibroblasts in the undesired tissue reactions caused by MoM THAs.


Assuntos
Artroplastia de Quadril , Fibroblastos/fisiologia , Próteses Articulares Metal-Metal , Idoso , Cromo , Cobalto , Feminino , Humanos , Macrófagos , Masculino , Metais , Pessoa de Meia-Idade , Membrana Sinovial
18.
Ren Fail ; 42(1): 580-586, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32576072

RESUMO

Background: Hospitalization is a significant outcome measurement for maintenance hemodialysis pantients. Trimethylamine-N-oxide (TMAO), created by gut microflora from dietary l-carnitine and choline, cleared by the kidney, has been implicated in the causation of cardiovascular diseases in patients with chronic kidney disease. However, whether it associates with hospitalization risk for these patients is unclear.Methods: In this study, 69 patients undergoing outpatient dialysis were enrolled. Enzyme-linked immunosorbent assay was used to quantitate the baseline plasma TMAO levels in patients. The patients were divided into a high TMAO level group (TMAO ≥ 15 µmol/L) and a low TMAO level group (TMAO < 15 µmol/L). During the 1-year follow-up, 1-year dialysis-related data and all-cause hospitalization events were recorded.Results: The incidence of hospitalization events was significantly higher in the high TMAO level group than in the low TMAO level group (91 per 100 patient-year vs. 32 per 100 patient-year). The Kaplain-Meier survaial analysis showed that the incidence of hospitalization events in the high TMAO level group was significantly higher than that in the low TMAO level group (log-rank p = 0.0004). After adjustment age, sex, CK-MB and albumin, the results of multivariate Cox proportional hazard analysis showed that high TMAO level was an independent risk factor for hospitalization in maintenance hemodialysis patients.Conclusion: TMAO is an independent risk factor for hospitalization events in patients receiving maintenance hemodialysis. It may be a new therapeutic target for improving the outcomes of these patients.


Assuntos
Doenças Cardiovasculares/mortalidade , Hospitalização/estatística & dados numéricos , Metilaminas/sangue , Diálise Renal , Insuficiência Renal Crônica/terapia , Idoso , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/mortalidade , Fatores de Risco , Análise de Sobrevida
19.
J Cell Mol Med ; 23(2): 1095-1105, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30411496

RESUMO

As a natural flavonol, fisetin has significant inhibitory effects on many cancers. Although fisetin can inhibit kidney cancer, its effects on kidney renal stem cells (HuRCSCs) remain unknown. Our study found that renal cancer tissues and CD44+/CD105+ HuRCSCs both show high TET1 protein expression. Both in vivo and in vitro experiments showed that fisetin can effectively inhibit HuRCSC cell division and proliferation, invasion, in vivo tumourigenesis and angiogenesis. Our findings showed that fisetin can significantly decrease TET1 expression levels in HuRCSCs and overall 5hmC levels in the genomes of these cells. At the same time, ChIP-PCR results showed that fisetin can effectively inhibit 5hmC modification levels at the CpG islands in cyclin Y (CCNY) and CDK16 and reduce their transcription and activity. Thus, we conclude that fisetin inhibits the epigenetic mechanism in renal cancer stem cells, that is, fisetin inhibits TET1 expression and reduces 5hmC modification in specific loci in the promoters of CCNY/CDK16 in HuRSCs. This in turn inhibits transcription of these genes, causing cell cycle arrest and ultimately inhibiting renal cancer stem cell activity.


Assuntos
Proliferação de Células/efeitos dos fármacos , Quinases Ciclina-Dependentes/genética , Ciclinas/genética , Flavonoides/farmacologia , Oxigenases de Função Mista/genética , Células-Tronco Neoplásicas/efeitos dos fármacos , Regiões Promotoras Genéticas/efeitos dos fármacos , Proteínas Proto-Oncogênicas/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Proliferação de Células/genética , Células Cultivadas , Ilhas de CpG/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Flavonóis , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Regiões Promotoras Genéticas/genética , Transcrição Gênica/efeitos dos fármacos
20.
Hum Brain Mapp ; 40(6): 1898-1907, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30565343

RESUMO

Decision-making in the somatosensory domain has been intensively studied using vibrotactile frequency discrimination tasks. Results from human and monkey electrophysiological studies from this line of research suggest that perceptual choices are encoded within a sensorimotor network. These findings, however, rely on experimental settings in which perceptual choices are inextricably linked to sensory and motor components of the task. Here, we devised a novel version of the vibrotactile frequency discrimination task with saccade responses which has the crucial advantage of decoupling perceptual choices from sensory and motor processes. We recorded human fMRI data from 32 participants while they performed the task. Using a whole-brain searchlight multivariate classification technique, we identify the left lateral prefrontal cortex and the oculomotor system, including the bilateral frontal eye fields (FEF) and intraparietal sulci, as representing vibrotactile choices. Moreover, we show that the decoding accuracy of choice information in the right FEF correlates with behavioral performance. Not only are these findings in remarkable agreement with previous work, they also provide novel fMRI evidence for choice coding in human oculomotor regions, which is not limited to saccadic decisions, but pertains to contexts where choices are made in a more abstract form.


Assuntos
Comportamento de Escolha/fisiologia , Discriminação Psicológica/fisiologia , Movimentos Sacádicos/fisiologia , Córtex Somatossensorial/fisiologia , Percepção do Tato/fisiologia , Adulto , Feminino , Lobo Frontal/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Somatossensorial/diagnóstico por imagem , Vibração , Percepção Visual/fisiologia , Adulto Jovem
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