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1.
Cancer Lett ; 594: 216992, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38797231

RESUMO

Intrahepatic cholangiocarcinoma (iCCA) is an aggressive cancer with an extremely poor prognosis, and new treatment options are needed. Recently, immunotherapy has emerged as an efficient treatment against malignant tumors, but less effective in iCCA. Activation of stimulator of interferon genes (STING) signaling could reignite immunologically inert tumors, but the expression and role of STING in iCCA remains to be determined. Here, we show STING is expressed in iCCA, and patients with high expression of STING in early-stage iCCA have a longer overall survival than those have low expression. Increased immune cell infiltration in early-stage iCCA corresponds to elevated STING expression. In mice iCCA models, treatment with the STING agonist MSA-2 show stage-specific inhibitory effects on tumors, with beneficial effects in early-stage tumors but not with advanced-stage cancer. This discrepancy was associated with greater programmed cell death ligand 1 (PD-L1) expression in advanced-stage tumors. Combination therapy targeting PD-L1 and MSA-2 strikingly reduced tumor burden in such tumors compared to either monotherapy. Cumulatively, these data demonstrate that STING agonism monotherapy improves the immune landscape of the tumor microenvironment in early-stage iCCA, while combination therapy ameliorates advanced-stage iCCA.

2.
Hepatology ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38683582

RESUMO

BACKGROUND AIMS: Hepatocellular carcinoma (HCC), particularly the multifocal HCC, features aggressive invasion and dismal prognosis. Locoregional treatments were often refractory to eliminate tumor tissue, resulting in residual tumor cells persisting and subsequent progression. Owing to problematic delivery to the tumor tissue, systemic therapies, such as lenvatinib (LEN) therapy, show limited clinical benefit in preventing residual tumor progression. Therefore, more advanced strategies for postablative multifocal HCC are urgently needed. APPROACH RESULTS: Motivated by the chemotaxis in tumor penetration of macrophages, we report a strategy named microinvasive ablation-guided macrophage hitchhiking (MAMH) for the targeted therapy toward HCC. In this study, the strategy leverages the natural inflammatory gradient induced by ablation to guide LEN-loaded macrophages toward tumor targeting, which increased by ~10-fold the delivery efficiency of LEN in postablative HCC in vivo. MAMH has demonstrated significant antitumor activity in various HCC models, including the hydrodynamic tail vein injection multifocal HCC mouse model and the orthotopic xenograft HCC rabbit model, systematically inhibiting residual tumor progression after ablation and prolonging the median survival of tumor-bearing mice. The potential antitumor mechanism was explored using techniques such as flow cytometry, enzyme-linked immunosorbent assay, and immunohistochemistry. We found that the strategy significantly suppressed tumor cell proliferation and neovascularization, and such enhanced delivery of LEN stimulated systemic immune responses and induced durable immune memory. CONCLUSIONS: The macrophage hitchhiking strategy demonstrates exceptional therapeutic efficacy and biosafety across various species, offering promising prospects for clinical translation in controlling residual tumor progression and improving outcomes following HCC ablation.

3.
Comput Biol Med ; 172: 108250, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38493603

RESUMO

Lung tumor segmentation in medical imaging is a critical step in the diagnosis and treatment planning for lung cancer. Accurate segmentation, however, is challenging due to the variability in tumor size, shape, and contrast against surrounding tissues. In this work, we present MSMV-Net, a novel deep learning architecture that integrates multi-scale multi-view (MSMV) learning modules and multi-scale uncertainty-based deep supervision (MUDS) for enhanced segmentation of lung tumors in computed tomography images. MSMV-Net capitalizes on the strengths of multi-view analysis and multi-scale feature extraction to address the limitations posed by small 3D lung tumors. The results indicate that MSMV-Net achieves state-of-the-art performance in lung tumor segmentation, recording a global Dice score of 55.60% on the LUNA dataset and 59.94% on the MSD dataset. Ablation studies conducted on the MSD dataset further validate that our method enhances segmentation accuracy.


Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Tórax , Tomografia Computadorizada por Raios X , Incerteza , Processamento de Imagem Assistida por Computador
4.
Nat Commun ; 15(1): 2546, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514647

RESUMO

Influenza virus continuously evolves to escape human adaptive immunity and generates seasonal epidemics. Therefore, influenza vaccine strains need to be updated annually for the upcoming flu season to ensure vaccine effectiveness. We develop a computational approach, beth-1, to forecast virus evolution and select representative virus for influenza vaccine. The method involves modelling site-wise mutation fitness. Informed by virus genome and population sero-positivity, we calibrate transition time of mutations and project the fitness landscape to future time, based on which beth-1 selects the optimal vaccine strain. In season-to-season prediction in historical data for the influenza A pH1N1 and H3N2 viruses, beth-1 demonstrates superior genetic matching compared to existing approaches. In prospective validations, the model shows superior or non-inferior genetic matching and neutralization against circulating virus in mice immunization experiments compared to the current vaccine. The method offers a promising and ready-to-use tool to facilitate vaccine strain selection for the influenza virus through capturing heterogeneous evolutionary dynamics over genome space-time and linking molecular variants to population immune response.


Assuntos
Vacinas contra Influenza , Influenza Humana , Humanos , Animais , Camundongos , Vacinas contra Influenza/genética , Vírus da Influenza A Subtipo H3N2/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Mutação , Estações do Ano
5.
Chem Commun (Camb) ; 59(54): 8388-8391, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37305995

RESUMO

Herein, we design a novel "crossbreeding" dye (BC-OH) within the second near-infrared (NIR-II) window based on BODIPY and chromene chromophores. BC-OH can serve as a platform to construct activatable NIR-II probes with small spectral crosstalk, thereby making a breakthrough in imaging in vivo H2O2 fluctuation in an APAP-induced liver injury model with high signal-to-background ratio.


Assuntos
Corantes Fluorescentes , Peróxido de Hidrogênio , Compostos de Boro , Fígado/diagnóstico por imagem , Imagem Óptica/métodos
6.
STAR Protoc ; 4(2): 102172, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36943863

RESUMO

Here, we present a protocol for the detection of the two STING isoforms (erSTING and pmSTING) in human peripheral blood mononuclear cells or mouse splenocytes using Western blot and PCR. We detail steps to construct plasmids encoding each isoform and transfer them into mouse and human cell lines. Finally, we describe how to detect cell membrane localization of pmSTING using flow cytometry, immunoprecipitation, and immunofluorescence. This protocol is applicable for proteins with well-predicted topological structures. For complete details on the use and execution of this protocol, please refer to Li et al.1.

7.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38189543

RESUMO

Recently, attention mechanism and derived models have gained significant traction in drug development due to their outstanding performance and interpretability in handling complex data structures. This review offers an in-depth exploration of the principles underlying attention-based models and their advantages in drug discovery. We further elaborate on their applications in various aspects of drug development, from molecular screening and target binding to property prediction and molecule generation. Finally, we discuss the current challenges faced in the application of attention mechanisms and Artificial Intelligence technologies, including data quality, model interpretability and computational resource constraints, along with future directions for research. Given the accelerating pace of technological advancement, we believe that attention-based models will have an increasingly prominent role in future drug discovery. We anticipate that these models will usher in revolutionary breakthroughs in the pharmaceutical domain, significantly accelerating the pace of drug development.


Assuntos
Inteligência Artificial , Descoberta de Drogas , Desenvolvimento de Medicamentos , Confiabilidade dos Dados
8.
Curr Gene Ther ; 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36017825

RESUMO

BACKGROUND: A novel CDK4/6 inhibitor SHR6390 has shown significant anti-tumor effects. However, its role in hepatocellular carcinoma(HCC) remains unknown. OBJECTIVE: To explore the inhibitory effect of combination treatment with SHR6390 and cabozantinib in HCC, and its antitumor mechanism, so as to provide more effective therapeutic strategy for HCC patients. METHODS: We investigated SHR6390, monotherapy or combined with cabozantinib, by CCK8, wound healing, transwell, western blotting, immunohistochemistry and mouse model of subcutaneous tumor. RESULTS: Our results show that SHR6390 exhibited potent anti-proliferative activity against HCC in a dose-dependent manner. SHR6390 combined with cabozantinib exhibited more potent inhibition of cell viability, migration and invasion. In terms of potential mechanisms, we found that cabozantinib could lead to phosphorylation of Rb, which was reduced in SHR6390 and combined groups. SHR6390 monotherapy inhibited the growth of subcutaneous HCC tumors, besides the combination treatment with SHR6390 and cabozantinib exerted synergistic anti-tumor activity in vivo. CONCLUSION: SHR6390 is effective against HCC, monotherapy or combined with cabozantinib.

9.
Nat Med ; 28(8): 1715-1722, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35710987

RESUMO

Timely evaluation of the protective effects of Coronavirus Disease 2019 (COVID-19) vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern is urgently needed to inform pandemic control planning. Based on 78 vaccine efficacy or effectiveness (VE) data from 49 studies and 1,984,241 SARS-CoV-2 sequences collected from 31 regions, we analyzed the relationship between genetic distance (GD) of circulating viruses against the vaccine strain and VE against symptomatic infection. We found that the GD of the receptor-binding domain of the SARS-CoV-2 spike protein is highly predictive of vaccine protection and accounted for 86.3% (P = 0.038) of the VE change in a vaccine platform-based mixed-effects model and 87.9% (P = 0.006) in a manufacturer-based model. We applied the VE-GD model to predict protection mediated by existing vaccines against new genetic variants and validated the results by published real-world and clinical trial data, finding high concordance of predicted VE with observed VE. We estimated the VE against the Delta variant to be 82.8% (95% prediction interval: 68.7-96.0) using the mRNA vaccine platform, closely matching the reported VE of 83.0% from an observational study. Among the four sublineages of Omicron, the predicted VE varied between 11.9% and 33.3%, with the highest VE predicted against BA.1 and the lowest against BA.2, using the mRNA vaccine platform. The VE-GD framework enables predictions of vaccine protection in real time and offers a rapid evaluation method against novel variants that may inform vaccine deployment and public health responses.


Assuntos
COVID-19 , Vacinas Virais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus , Eficácia de Vacinas , Vacinas Sintéticas , Vacinas de mRNA
10.
J Clin Invest ; 132(3)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34905508

RESUMO

It has been revealed that 2'3'-cyclic-GMP-AMP (cGAMP), a second messenger that activates the antiviral stimulator of IFN genes (STING), elicits an antitumoral immune response. Since cGAMP cannot cross the cell membrane, it is not clear how intracellular STING has been activated by extracellular cGAMP until SLC19A1 was identified as an importer to transport extracellular cGAMP into the cytosol. However, SLC19A1-deficient cells also sense extracellular cGAMP, suggesting the presence of mechanisms other than the facilitating transporters for STING sensing extracellular cGAMP. Here, using immunoprecipitation, immunofluorescence, and flow cytometry, we identified an alternatively spliced STING isoform, plasmatic membrane STING (pmSTING), that localized in the plasma membrane with its C-terminus outside the cell, due to a lack of 1 transmembrane domain in its N-terminus compared with canonical STING. Further studies showed that extracellular cGAMP not only promoted the dimerization of pmSTING and interaction of pmSTING with TANK-binding kinase 1 (TBK1) and IFN regulatory factor 3 (IRF3), but also enhanced the phosphorylation of TBK1 and IRF3 and the production of IFN in pmSTING-transfected cells. Additionally, we also identified similar pmSTING isoforms in other species including human. This study suggests a conserved role for pmSTING in sensing extracellular cGAMP and provides insight into the role of cGAMP as an immunotransmitter.


Assuntos
Processamento Alternativo , Membrana Celular/metabolismo , Proteínas de Membrana/biossíntese , Nucleotídeos Cíclicos/metabolismo , Transdução de Sinais , Membrana Celular/genética , Células HEK293 , Humanos , Proteínas de Membrana/genética , Nucleotídeos Cíclicos/genética
11.
Front Plant Sci ; 12: 783388, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34912363

RESUMO

Members of the R2R3-MYB transcription factor superfamily have been implicated in plant development, improved disease resistance, and defense responses to several types of stresses. To study the function of TaMYB29 transcription factor-a member of the R2R3-MYB superfamily-in response to an avirulent race of stripe rust pathogen, Puccinia striiformis f. sp. tritici (Pst), we identified and cloned the TaMYB29 gene from wheat cultivar (cv.) AvS+Yr10 following infection with Pst. The TaMYB29 protein, comprising 261 amino acids, contains two highly conserved MYB domains. We first showed that TaMYB29 is a transcription factor, whose transcriptional levels are significantly induced by salicylic acid (SA), abscisic acid (ABA), jasmonic acid (JA), ethylene (ET), and Pst. The results showed that TaMYB29 is involved in the wheat response to stipe rust. The overexpression of the TaMYB29 gene resulted in the accumulation of reactive oxygen species (ROS) and pathogen-independent cell death in Nicotiana benthamiana leaves. The silencing of TaMYB29 gene in wheat cv. AvS+Yr10, containing the stripe rust resistance gene Yr10, promoted hyphae growth, significantly downregulated the expression of pathogenesis-related (PR) genes, and substantially reduced the wheat resistance to Pst compared with the non-silenced control. In addition, the accumulation of hydrogen peroxide (H2O2) significantly decreased, and the activity of catalase, an enzyme required for H2O2 scavenging, was elevated. Altogether, TaMYB29 positively regulates the defense response against stripe rust in wheat AvS+Yr10 by enhancing H2O2 accumulation, PR gene expression, and SA signaling pathway-induced cell death. These results provide new insights into the contribution of TaMYB29 to the defense response against rust pathogens in wheat.

12.
Therap Adv Gastroenterol ; 14: 1756284821989177, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262609

RESUMO

Helicobacter pylori (HP) is a major causative agent of chronic gastritis and peptic ulcer. HP is also engaged in the development of gastric cancer and gastric mucosa-associated lymphoid tissue lymphoma. It is an important pathogenic factor in various other systemic diseases, such as vitamin B12 deficiency, iron deficiency, and idiopathic thrombocytopenia. The current consensus is that unless there is a special reason, eradication therapy should be implemented whenever HP infection is found, and it is ideally successful the first time. International guidelines recommend that under certain conditions, treatment should be personalized based on drug susceptibility testing. However, drug susceptibility testing is often not available because it is expensive, time-consuming, and difficult to obtain living tissue. Each region has separately formulated guidelines or consensuses on empirical therapy. Owing to an increasing drug resistance rate in various places, the eradication rate of proton pump inhibitor (PPI) triple therapy and sequential therapy has been affected. These regimens are rarely used; the PPI triple especially has been abandoned in most areas. Currently, radical treatment regimens for HP involve bismuth-containing quadruple therapy and concomitant therapy. However, quadruple therapy has its own limitations, such as complex drug administration. To improve the effectiveness, safety, and compliance, many clinical studies have proposed useful modified regimens, which mainly include the modified bismuth-containing quadruple regimen, high-dose dual therapy, and vonoprazan-containing regimens. Studies have shown that these emerging regimens have acceptable eradication rates and safety, and are expected to become first-line treatments in empirical therapy. However, the problem of decline in the eradication rate caused by drug resistance has not been fundamentally solved. This review not only summarizes the effectiveness of mainstream regimens in the first-line treatment of HP infection with the currently increasing antibiotic resistance rates, but also summarizes the effectiveness and safety of various emerging treatment regimens.

13.
Cell Immunol ; 366: 104384, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34182334

RESUMO

Despite impressive clinical success, cancer immunotherapy based on immune checkpoint blockade remains ineffective in colorectal cancer (CRC). Stimulator of interferon genes (STING) is a novel potential target and STING agonists have shown potential anti-tumor efficacy. Combined therapy based on synergistic mechanism can overcome the resistance. However, STING agonists-based combination therapies are deficient. We designed different immunotherapy combinations, including STING agonist, indoleamine 2,3 dioxygenase (IDO) inhibitor and PD-1 blockade, with purpose of exploring which option can effectively inhibit CRC growth. To further explore the possible reasons of therapeutic effectiveness, we observed the combination therapy in C57BL/6Tmem173gt mice. Our findings demonstrated that STING agonist diABZI combined with IDO inhibitor 1-MT significantly inhibited tumor growth, even better than the three-drug combination, promoted the recruitment of CD8+ T cells and dendritic cells, and decreased the infiltration of myeloid-derived suppressor cells. We conclude that diABZI combined with 1-MT is a promising option for CRC.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzimidazóis/uso terapêutico , Linfócitos T CD8-Positivos/imunologia , Neoplasias Colorretais/tratamento farmacológico , Imunoterapia/métodos , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Proteínas de Membrana/agonistas , Células Supressoras Mieloides/imunologia , Triptofano/uso terapêutico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Benzimidazóis/farmacologia , Carcinogênese , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Triptofano/farmacologia
14.
Front Oncol ; 11: 654076, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34046350

RESUMO

PURPOSE: Colon cancer (CC) is a serious disease burden. The prognosis of patients with CC is different, so looking for effective biomarkers to predict prognosis is vitally important. Ferroptosis is a promising therapeutic and diagnosis strategy in CC. However, the role of ferroptosis in prognosis of CC has not been studied. The aim of the study is to build a prognosis model related ferroptosis, and provide clues for further therapy of CC. METHODS: The RNA-seq data were from TCGA (training group) and GEO (testing group). The R language and Perl language were used to process and analyze data. LASSO regression analysis was used to build the prognosis model. ssGSEA was used to compare the immune status between two groups. Immunohistochemistry was used to detect expression of AKR1C1 and CARS1 in colon cancer tissues and adjacent tissues. RESULTS: The prognosis model consisted of five ferroptosis related genes (AKR1C1, ALOX12, FDFT1, ATP5MC3, and CARS1). The area under curve (AUC) at 1-, 2-, and 3-year were 0.668, 0.678, and 0.686, respectively. The high- and low-risk patients had significant survival probability and could be clearly distinguished by the PCA and t-SNE analysis. The multivariate cox regression analysis also showed the riskscore is an independent prognosis factor. Importantly, we found that the immune status between high- and low-risk patients were different obviously, such as CD8+T cells. And STING, a new promising immune target, was also correlated to our signature genes statistically significantly. CONCLUSION: Our ferroptosis prognosis signature could predict survival of CC patients to a certain degree. And the crosstalk between ferroptosis and immune, especially STING need further studies.

15.
Front Oncol ; 10: 562950, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33585187

RESUMO

Sirtuins (SIRTs) are members of the silent information regulator-2 family. They are a conserved family of nicotinamide adenine dinucleotide-dependent protein lysine deacylases. SIRTS are involved in intricate cellular processes. There are seven subtypes of SIRTs (1-7) in mammals. SIRT4 is located mainly in mitochondria and has various catalytic activities. These enzyme activities give it a diverse range of important biologic functions, such as energy metabolism, oxidative stress, and aging. Cancer is characterized as reprogramming of energy metabolism and redox imbalance, and SIRT4 can affect tumorigenesis. Here, we review the structure, localization, and enzyme activity of SIRT4 and its role in various neoplasms.

16.
Oncol Res ; 27(8): 965-978, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-30940297

RESUMO

Toll-like receptors (TLRs) are associated with tumor growth and immunosuppression, as well as apoptosis and immune system activation. TLRs can activate apoptosis and innate and adaptive immunity pathways, which can be pharmacologically targeted for the development of anticancer oncotherapies. Several studies and clinical trials indicate that TLR agonists are promising adjuvants or elements of novel therapies, particularly when used in conjunction with chemotherapy or radiotherapy. An increasing number of studies suggest that the activation of TLRs in various cancer types is related to oncotherapy; however, before this finding can be applied to clinical practice, additional studies are required. Research suggests that TLR agonists may have potential applications in cancer therapy; nevertheless, because TLR signaling can also promote tumorigenesis, a critical and comprehensive evaluation of TLR action is warranted. This review focuses on recent studies that have assessed the strengths and weaknesses of utilizing TLR agonists as potential anticancer agents.


Assuntos
Apoptose/genética , Terapia de Alvo Molecular , Neoplasias/terapia , Receptores Toll-Like/genética , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Humanos , Neoplasias/genética , Neoplasias/patologia , Receptores Toll-Like/antagonistas & inibidores
17.
Int J Biol Macromol ; 121: 161-172, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30290264

RESUMO

A new water-soluble polysaccharide, APS-1II, with a molecular weight of 42.1 kDa was isolated from the roots of Angelica sinensis (Oliv.) Diels. APS-1II consists of arabinose (Ara), glucose (Glc) and fucose (Fuc) with a molar ratio of 2.48:1.05:1.00. The backbone of APS-1II is composed of 1,3-α-l-Araf and 1,6-α-d-Glcp with the branches containing 1,5-α-l-Araf, 1,4-ß-d-Glcp, T-ß-d-Glcp, 1,3-α-l-Fucp and T-α-l-Fucp. APS-1II inhibited the proliferation of human leukemia K562 and mouse L1210 cells in vitro and markedly prolonged the life span of L1210-bearing mice in vivo. APS-1II also increased the numbers of leukocytes and lymphocytes in peripheral blood, and significantly decreased plasma tumor necrosis factor, interleukin-2 and interferon-γ levels in L1210-bearing mice. Moreover, APS-1II administration concentration-dependently promoted the proliferation of the splenocytes, enhanced phagocytic activity of peritoneal macrophages and cytotoxicity of natural killer cells. These results suggest that APS-1II could effectively inhibit leukemia and induce a protective immune response, and it may be used as a suitable candidate reagent for leukemia therapy.


Assuntos
Angelica sinensis/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Leucemia/tratamento farmacológico , Polissacarídeos/química , Polissacarídeos/farmacologia , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Humanos , Hidrólise , Células K562 , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Leucemia/imunologia , Leucemia/patologia , Masculino , Camundongos , Peso Molecular , Monossacarídeos/análise , Fagócitos/efeitos dos fármacos , Polissacarídeos/uso terapêutico , Baço/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Acta Odontol Scand ; 72(8): 664-72, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24580092

RESUMO

OBJECTIVE: The aim of this study was to investigate the chondrogenic potential of stem cells from human exfoliated teeth (SHED). MATERIALS AND METHODS: SHED cultures were isolated from human exfoliated deciduous teeth. Colony-forming capacity, odonto/osteogenic and adipogenic potential were measured. SHED were cultured for 2 weeks in chondrogenic differentiation medium containing dexamethasone, insulin, ascorbate phosphate, TGF-ß3 and bFGF. Toluidine blue staining and safranin O staining were used for chondrogenesis analysis. The related markers, type II collagen and aggrecan, were also investigated using immunohistochemistry. SHED were seeded onto the ß-TCP scaffolds and transplanted into the subcutaneous space on the back of nude mice. The transplants were recovered at 2, 4 and 8 weeks post-transplantation for analysis. RESULTS: SHED showed colony-forming capacity, odonto/osteogenic and adipogenic differentiation capacity. Chondrogenic differentiation was confirmed by toluidine blue staining, safranin O staining, type II collagen and aggrecan immunostaining. After in vivo transplantation, SHED recombined with ß-TCP scaffolds were able to generate new cartilage-like tissues. CONCLUSIONS: The findings demonstrate the chondrogenic differentiation capacity of SHED both in vitro and in vivo models, suggesting the potential of SHED in cartilage tissue engineering.


Assuntos
Condrogênese/fisiologia , Células-Tronco/fisiologia , Dente Decíduo/citologia , Adipogenia/fisiologia , Agrecanas/análise , Animais , Fosfatos de Cálcio/química , Cartilagem/anatomia & histologia , Técnicas de Cultura de Células , Diferenciação Celular/fisiologia , Sobrevivência Celular/fisiologia , Criança , Colágeno Tipo II/análise , Corantes , Meios de Cultura , Polpa Dentária/citologia , Humanos , Camundongos , Camundongos Nus , Odontogênese/fisiologia , Osteogênese/fisiologia , Fenazinas , Transplante de Células-Tronco/métodos , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Cloreto de Tolônio
19.
Nan Fang Yi Ke Da Xue Xue Bao ; 33(10): 1512-6, 2013 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-24144758

RESUMO

OBJECTIVE: To regenerate dentin-pulp complex by tissue engineering with human stem cells from apical papilla cells (SCAP) as the seed cells. METHODS: SCAP was separated from from normal human impacted third molars with immature roots by outgrowth culture. The cells were then cultured in the differentiation medium for 3 weeks or in normal medium for 60 days, and analyzed for mineralization potential by Alizarin red staining. The osteo/odontogenic markers including alkaline phosphatase (ALP), bone sialoprotein (BSP), osteocalcin (OC) and dentin sialoprotein (DSP) were investigated by immunofluorescence staining and reverse transcription-polymerase chain reaction. The co-cultured mixture of SCAP and HA/TCP, or HA/TCP alone was implanted subcutaneously on the back of nude mice for 8 weeks, and the implants were collected and examined by HE and immunohistochemical staining. RESULTS: Round alizarin red-positive nodules formed in the isolated cells after cell culture in the differentiation medium for 3 weeks or in normal medium for 60 days with positive staining for osteo/odontogenic markers. SCAP with HA/TCP could regenerate pulp-dentin complex-like tissue in nude mice. The cells near the dentin-like tissue were positive for DSP. No mineral tissue was found in mice receiving HA/TCP implantation. CONCLUSIONS: SCAP may serve as a promising seed cell for dentin-pulp complex tissue engineering.


Assuntos
Papila Dentária/citologia , Polpa Dentária/citologia , Odontogênese/fisiologia , Células-Tronco/fisiologia , Engenharia Tecidual/métodos , Adolescente , Adulto , Fosfatase Alcalina/análise , Animais , Técnicas de Cultura de Células , Diferenciação Celular , Técnicas de Cocultura , Proteínas da Matriz Extracelular/análise , Feminino , Humanos , Sialoproteína de Ligação à Integrina/análise , Camundongos , Camundongos Nus , Osteocalcina/análise , Fosfoproteínas/análise , Sialoglicoproteínas/análise , Células-Tronco/química , Adulto Jovem
20.
Nan Fang Yi Ke Da Xue Xue Bao ; 33(5): 776-8, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-23689006

RESUMO

OBJECTIVE: To observe the effect of revascularization for treatment of immature teeth with endodontic infection mediated by calcium hydroxide. METHODS: Seventeen pediatric patients with endodontic infections of the permanent teeth were treated with routine root canal and pulp cavity irrigation and disinfection followed by application of calcium hydroxide paste to the root canal orifice to induce revascularization. Another 17 patients received conventional apexification procedures to serve as the control group. The patients were followed up to observe the therapeutic effect of the treatments. RESULTS: In the revascularization treatment group, 4 cases showed healed periapical lesions 6 to 18 months after the surgery with thickened root canal walls and closure of the apical foramen; in 10 cases, the periapical lesions healed 12 to 18 months postoperatively with lengthened root, thickened root canal wall, and narrowed apical foramen. One patient reported pain and swelling at 2 months, and 2 patients showed the formation of gum fistula and ceased development of the roots at 7 and 8 months. In the control group, the periapical lesions healed in 1 cases at 12 months postoperatively with apical foramen closure; in 11 cases, hard tissues formed in the root apex without obviously lengthened roots 6 to 8 months after the surgery; in 5 cases, no apical barrier formed even 12 to 18 months after the surgery. The overall effective rates were similar between the two groups (P>0.05). CONCLUSIONS: Revascularization by calcium hydroxide sealing can promote root development of immature permanent teeth with pulpitis or periradicular periodontitis.


Assuntos
Hidróxido de Cálcio/uso terapêutico , Doenças da Polpa Dentária/terapia , Polpa Dentária/irrigação sanguínea , Dentição Permanente , Regeneração Tecidual Guiada Periodontal , Adolescente , Criança , Humanos , Neovascularização Fisiológica/efeitos dos fármacos , Resultado do Tratamento
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