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The trophoblast lineage differentiation represents a rate-limiting step in successful embryo implantation. Adhesion, invasion and migration processes within the trophoblast are governed by several transcription factors. Among them, CDX2 is a critical regulator shaping the destiny of the trophoblast. While its altered expression is a linchpin initiating embryo implantation in mice, the precise influence of CDX2 on the functionality and lineage differentiation of early human trophoblast remains unclear. In this study, we employed well-established human trophoblast stem cell (hTSC) lines with CDX2 overexpression coupled with a 3D in vitro culture system for early human embryos. We revealed that the downregulation of CDX2 is a prerequisite for syncytialization during human embryo implantation based on immunofluorescence, transcriptome analysis, CUT-tag sequencing and the construction of 3D human trophoblast organoids. While CDX2 overexpression inhibited syncytialization, it propelled hTSC proliferation and invasive migration. CDX2 exerted its influence by interacting with CGA, PTGS2, GCM1, LEF1 and CDH2, thereby hindering premature differentiation of the syncytiotrophoblast. CDX2 overexpression enhanced the epithelial-mesenchymal transition of human trophoblast organoids. In summary, our study provides insights into the molecular characteristics of trophoblast differentiation and development in humans, laying a theoretical foundation for advancing research in embryo implantation.
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One of the most common neurodegenerative illnesses is Parkinson's disease (PD). Rotigotine (RTG) is a dopamine agonist that exerts anti-Parkinsonian effects through dopamine receptor agonism to improve motor symptoms and overall performance in PD patients. In this study, an in situ liquid crystal gel called rotigotine-gel (RTG-gel) was developed using soya phosphatidyl choline (SPC) and glycerol dioleate (GDO) to provide long-acting slow-release benefits of rotigotine while minimizing side effects. This study prepared the RTG-gel precursor solution using SPC, GDO, and ethanol (in the ratio of 54:36:10, w/w/w). The internal structures of the gel were confirmed by crossed-polarized light microscopy (PLM), small-angle X-ray scattering (SAXS), and differential scanning calorimetry (DSC). The rheological properties of the RTG-gel precursor solution indicate a favorable combination of low viscosity and excellent flowability. The gel that produced during water absorption was also highly viscous and structurally stable, which helped to maintain the drug delayed release at the injection site. In vitro release assays showed that the in vitro release of RTG-gel followed Ritger-Peppas. The RTG-gel precursor solution was administered by subcutaneous injection, and the results of in vivo pharmacokinetic tests in SD rats showed that the plasma elimination half-life (t1/2) was 59.28 ± 16.08 h; the time to peak blood concentration (Tmax) was 12.00 ± 10.32 h, and the peak concentration (Cmax) was 29.9 ± 10.10 ng/mL. The blood concentration remained above 0.1 ng/mL for 20 days after administration and was still detectable after 31 days of administration, and the bioavailability of RTG can reach 72.59%. The results of in vitro solvent exchange tests showed that the RTG-gel precursor solution undergoes rapid exchange upon contact with PBS, and the diffusion of ethanol can reach 48.1% within 60 min and 80% within 8 h. The results of cytotoxicity test showed 89.27 ± 4.32% cell survival after administration of the drug using RTG-gel. The results of tissue extraction at the administration site showed that healing of the injection site without redness and hemorrhage could be observed after 14 days of injection. The results of tissue section of the administered site showed that the inflammatory cells decreased and granulation tissue appeared after 14 days of administration, and there was basically no inflammatory cell infiltration after 35 days of administration, and the inflammatory reaction was basically eliminated. It shows that RTG-gel has some irritation to the injection site, but it can be recovered by itself in the later stage, and it has good biocompatibility. In summary, RTG-gel might be a potential RTG extended-release formulation for treating PD.
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Cristais Líquidos , Doença de Parkinson , Tetra-Hidronaftalenos , Tiofenos , Humanos , Ratos , Animais , Doença de Parkinson/tratamento farmacológico , Cristais Líquidos/química , Espalhamento a Baixo Ângulo , Ratos Sprague-Dawley , Difração de Raios X , Agonistas de Dopamina/efeitos adversos , Injeções Subcutâneas , EtanolRESUMO
Studies of cultured embryos have provided insights into human peri-implantation development. However, detailed knowledge of peri-implantation lineage development as well as underlying mechanisms remains obscure. Using 3D-cultured human embryos, herein we report a complete cell atlas of the early post-implantation lineages and decipher cellular composition and gene signatures of the epiblast and hypoblast derivatives. In addition, we develop an embryo-like assembloid (E-assembloid) by assembling naive hESCs and extraembryonic cells. Using human embryos and E-assembloids, we reveal that WNT, BMP and Nodal signaling pathways synergistically, but functionally differently, orchestrate human peri-implantation lineage development. Specially, we dissect mechanisms underlying extraembryonic mesoderm and extraembryonic endoderm specifications. Finally, an improved E-assembloid is developed to recapitulate the epiblast and hypoblast development and tissue architectures in the pre-gastrulation human embryo. Our findings provide insights into human peri-implantation development, and the E-assembloid offers a useful model to disentangle cellular behaviors and signaling interactions that drive human embryogenesis.
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Embrião de Mamíferos , Camadas Germinativas , Humanos , Embrião de Mamíferos/metabolismo , Implantação do Embrião , Endoderma , Mesoderma/metabolismo , Desenvolvimento EmbrionárioRESUMO
In recent years, biodegradable polymers have gained the attention of many researchers for their promising applications, especially in drug delivery, due to their good biocompatibility and designable degradation time. Poly (lactic-co-glycolic acid) (PLGA) is a biodegradable functional polymer made from the polymerization of lactic acid (LA) and glycolic acid (GA) and is widely used in pharmaceuticals and medical engineering materials because of its biocompatibility, non-toxicity, and good plasticity. The aim of this review is to illustrate the progress of research on PLGA in biomedical applications, as well as its shortcomings, to provide some assistance for its future research development.
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BACKGROUND AND AIM: Liver cancer stem cells (LCSCs) cause therapeutic refractoriness and relapse in hepatocellular carcinoma. Heat shock factor 1 (HSF1) plays versatile roles in multiple cancers. However, the role of HSF1 in LCSCs is not well understood. This study investigated the function and signal mechanisms of HSF1 in maintaining LCSC phenotypes. METHODS: We established two LCSC lines, HepG2-R and HuH-7-R. Constitutive activation of HSF1 was observed in these LCSCs. Specific short hairpin RNAs (shRNAs) and chemical inhibitors were used to identify the relationship between HSF1 expression and LCSCs phenotypes. RESULTS: We revealed a concomitant activation modality involving HSF1 and STAT3 in LCSCs and liver cancer tissues. We also found that liver cancer patients whose HSF1 and STAT3 mRNA expression levels were high presented with unfavorable clinicopathological characteristics. Moreover, the secretion of interleukin-8 (IL-8) was elevated in the LCSC medium and was directly regulated by HSF1 at the transcriptional level. In turn, IL-8 activated HSF1 and STAT3 signaling, and a neutralizing IL-8 antibody inhibited HSF1 and STAT3 activity, reduced cancer stem cell marker expression, and decreased LCSC microsphere formation. Simultaneous intervention with HSF1 and STAT3 led to synergistically suppressed stemness acquisition and growth suppression in the LCSCs in vivo and in vitro. CONCLUSIONS: Our study indicates that IL-8 mediates the crosstalk between the HSF1 and Stat3 signaling pathways in LCSCs and that the combined targeting of HSF1 and STAT3 is a promising treatment strategy for patients with advanced liver cancer.
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Fatores de Transcrição de Choque Térmico , Neoplasias Hepáticas , Células-Tronco Neoplásicas , Fator de Transcrição STAT3 , Humanos , Comunicação Autócrina , Linhagem Celular Tumoral , Fatores de Transcrição de Choque Térmico/metabolismo , Interleucina-8/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de SinaisRESUMO
The peri-implantation period from blastula to gastrula is one of the crucial stages of human embryo and stem cell development. During development, human embryos undergo many crucial events, such as embryonic lineage differentiation and development, structural self-assembly, pluripotency state transition, cell communication between lineages, and crosstalk between the embryo and uterus. Abnormalities in these developmental events will result in implantation failure or pregnancy loss. However, because of ethical and technical limits, the developmental dynamics of human peri-implantation embryos and the underlying mechanisms of abnormal development remain in a "black box." In this review, we summarize recent progress made toward our understanding of human peri-implantation embryogenesis based on extended in vitro cultured embryos and stem cell-based embryoids. These findings lay an important foundation for understanding early life, promoting research into human stem cells and their application, and preventing and treating infertility. We also propose key scientific issues regarding peri-implantation embryogenesis and provide an outlook on future study directions. Finally, we sum up China's contribution to the field and future opportunities.
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Implantação do Embrião , Infertilidade , Blastocisto , Diferenciação Celular , Embrião de Mamíferos , Desenvolvimento Embrionário , Feminino , Humanos , GravidezRESUMO
Precise gene regulation is critical during embryo development. Long terminal repeat elements (LTRs) of endogenous retroviruses (ERVs) are dynamically expressed in blastocysts of mammalian embryos. However, the expression pattern of LTRs in monkey blastocyst is still unknown. By single-cell RNA-sequencing (seq) data of cynomolgus monkeys, we found that LTRs of several ERV families, including MacERV6, MacERV3, MacERV2, MacERVK1, and MacERVK2, were highly expressed in pre-implantation embryo cells including epiblast (EPI), trophectoderm (TrB), and primitive endoderm (PrE), but were depleted in post-implantation. We knocked down MacERV6-LTR1a in cynomolgus monkeys with a short hairpin RNA (shRNA) strategy to examine the potential function of MacERV6-LTR1a in the early development of monkey embryos. The silence of MacERV6-LTR1a mainly postpones the differentiation of TrB, EPI, and PrE cells in embryos at day 7 compared to control. Moreover, we confirmed MacERV6-LTR1a could recruit Estrogen Related Receptor Beta (ESRRB), which plays an important role in the maintenance of self-renewal and pluripotency of embryonic and trophoblast stem cells through different signaling pathways including FGF and Wnt signaling pathways. In summary, these results suggest that MacERV6-LTR1a is involved in gene regulation of the pre-implantation embryo of the cynomolgus monkeys.
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Blastocisto/metabolismo , Retrovirus Endógenos/genética , Sequências Repetidas Terminais/genética , Animais , Desenvolvimento Embrionário/genética , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Ontologia Genética , Macaca fascicularis , Células-Tronco Pluripotentes/metabolismo , Fatores de Tempo , Transcriptoma/genéticaRESUMO
Inflammasome is a complex composed of several proteins and an important part of the natural immune system. Nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome is composed of NLRP3, apoptosis associated speck like protein (ASC) and pro-caspase-1. It plays an important role in many diseases. Hydrogen sulfide (H2S) is an important signaling molecule that regulates many physiological and pathological processes. Recent studies indicated that H2S played anti-inflammatory and pro-inflammatory roles in many diseases through influencing NLRP3 inflammasome, but its mechanism was not fully understood. This article reviewed the progress about the effects of H2S on NLRP3 inflammasome and its mechanisms involved in recent years to provide theoretical basis for in-depth study.
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Sulfeto de Hidrogênio/metabolismo , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Diabetes Mellitus/metabolismo , Humanos , Macrófagos/metabolismo , NeuroproteçãoRESUMO
BACKGROUND: Considerable progress has been made in converting human pluripotent stem cells (hPSCs) into cortical neurons for disease modeling and regenerative medicine. However, these procedures are hard to provide sufficient cells for their applications. Using a combination of small-molecules and growth factors, we previously identified one condition which can rapidly induce hPSCs into neuroepithelial stem cells (NESCs). Here, we developed a scalable suspension culture system, which largely yields high-quality NESC-spheres and subsequent cortical neurons. METHODS: The NESC medium was first optimized, and the suspension culture system was then enlarged from plates to stirred bioreactors for large-scale production of NESC-spheres by a stirring speed of 60 rpm. During the expansion, the quality of NESC-spheres was evaluated. The differentiation potential of NESC-spheres into cortical neurons was demonstrated by removing bFGF and two pathway inhibitors from the NESC medium. Cellular immunofluorescence staining, global transcriptome, and single-cell RNA sequencing analysis were used to identify the characteristics, identities, purities, or homogeneities of NESC-spheres or their differentiated cells, respectively. RESULTS: The optimized culture system is more conducive to large-scale suspension production of NESCs. These largely expanded NESC-spheres maintain unlimited self-renewal ability and NESC state by retaining their uniform sizes, high cell vitalities, and robust expansion abilities. After long-term expansion, NESC-spheres preserve high purity, homogeneity, and normal diploid karyotype. These expanded NESC-spheres on a large scale have strong differentiation potential and effectively produce mature cortical neurons. CONCLUSIONS: We developed a serum-free, defined, and low-cost culture system for large-scale expansion of NESCs in stirred suspension bioreactors. The stable and controllable 3D system supports long-term expansion of high-quality and homogeneous NESC-spheres. These NESC-spheres can be used to efficiently give rise to cortical neurons for cell therapy, disease modeling, and drug screening in future.
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Técnicas de Cultura de Células , Células-Tronco Pluripotentes , Reatores Biológicos , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , NeurôniosRESUMO
Various culture systems have been used to derive and maintain human pluripotent stem cells (hPSCs), but they are inefficient in sustaining cloning and suspension expansion of hPSCs. Through systematically modulating Wnt and Activin/Nodal signaling, we developed a defined medium (termed AIC), which enables efficient cloning and long-term expansion of hPSCs (AIC-hPSCs) through single-cell passage on feeders, matrix or in suspension (25-fold expansion in 4 days) and maintains genomic stability of hPSCs over extensive expansion. Moreover, the AIC medium supports efficient derivation of hPSCs from blastocysts or somatic cells under feeder-free conditions. Compared to conventional hPSCs, AIC-hPSCs have similar gene expression profiles but down-regulated differentiation genes and display higher metabolic activity. Additionally, the AIC medium shows a good compatibility for different hPSC lines under various culture conditions. Our study provides a robust culture system for derivation, cloning and suspension expansion of high-quality hPSCs that benefits GMP production and processing of therapeutic hPSC products.
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Ativinas , Células-Tronco Pluripotentes , Técnicas de Cultura de Células , Diferenciação Celular , Clonagem Molecular , HumanosRESUMO
Monkeys are an optimal model species for developing stem cell therapies. We previously reported generating chimeric cynomolgus monkey fetuses using dome-shaped embryonic stem cells (dESCs). However, conventional primed pluripotent stem cells (pPSCs) lack chimera competency. Here, by altering the media in which injected morulae are cultured, we observed increased survival of cynomolgus monkey primed ESCs, induced PSCs, and somatic cell nuclear transfer-derived ESCs, thereby enabling chimeric contributions with 0.1%-4.5% chimerism into the embryonic and placental tissues, including germ cell progenitors in chimeric monkeys. Mechanically, dESCs and pPSCs belong to different cell types and similarly express epiblast ontogenic genes. The host embryonic microenvironment could reprogram injected PSCs to embryonic-like cells. However, the reprogramming level and chimerism were associated with the cell state of injected PSCs. Our findings provide a method to understand pluripotency and broaden the use of embryonic chimeras for basic developmental biology research and regenerative medicine.
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Quimerismo , Embrião de Mamíferos/citologia , Injeções , Células-Tronco Pluripotentes/citologia , Animais , Animais Recém-Nascidos , Sobrevivência Celular , Microambiente Celular , Reprogramação Celular , Técnicas de Cultura Embrionária , Regulação da Expressão Gênica , Macaca fascicularis , Células-Tronco Pluripotentes/metabolismo , Trofoblastos/citologiaRESUMO
The metastasis is one of the greatest challenges for successful cancer therapy. Herein, we report a lipid-coated nanodiamond (ND) system loading water-insoluble sorafenib (SND) to improve the bioavailability and efficacy on suppression of cancer metastasis. SND was homogenous nanoassemblies with the mean diameter of 127.6 ± 12.9 nm. Compared with the drug suspension, the sorafenib concentration in gastrointestinal (GI) tract and major organs was significantly increased by SND. Moreover, the oral bioavailability of sorafenib was greatly improved 7.64-fold by SND. However, the ND in SND could not be absorbed into the mucus of GI tract or distributed into major organs after oral administration. Furthermore, the sorafenib concentration in tumor tissue was markedly improved 14.95 folds by SND, and SND demonstrated an efficient and impressive tumor growth inhibition effect in tumor xenograft models. In particular, the metastasis of gastric cancer to distant organs of liver and kidney was remarkably suppressed by SND, which was verified by the detection of macroscopic metastatic nodules, histological examination and immunofluorescence measurements. Thereby, the lipid-coated ND could be a promising drug delivery platform for improving the oral bioavailability of lipophilic drugs and treatment of cancer metastasis.
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Antineoplásicos/administração & dosagem , Portadores de Fármacos/química , Lipídeos/química , Nanodiamantes/química , Metástase Neoplásica/prevenção & controle , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Neoplasias Gástricas/tratamento farmacológico , Administração Oral , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Disponibilidade Biológica , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica/patologia , Niacinamida/administração & dosagem , Niacinamida/farmacocinética , Niacinamida/uso terapêutico , Compostos de Fenilureia/farmacocinética , Compostos de Fenilureia/uso terapêutico , Sorafenibe , Estômago/efeitos dos fármacos , Estômago/patologia , Neoplasias Gástricas/patologiaRESUMO
PURPOSE: We are reporting on the development of a unique drug delivery platform by directed self-assembly technique to improve the oral delivery of hydrophobic drugs. METHODS: Herein, a series of probucol directed self-assembled nanoparticles (PDN) were developed with two components of probucol and surfactant such as Tween 20, Tween 80, D-alpha-tocopheryl polyethylene glycol 1,000 succinate (TPGS) and HS-15, which was respectively named as T20-PDN, T80-PDN, TP-PDN and HS-PDN. The formation of various PDNs was determined by in vitro characterization and the physicochemical properties of these PDNs were determined. Moreover, the performance of PDN in enhancing the oral delivery and possible correlation between the in vitro properties and in vivo performances were investigated. RESULTS: PDN was homogenous nanometer-sized particles with negative surface charge. The cellular uptake of probucol in Caco-2 cell monolayer was respectively increased 1.15, 1.82, 1.59 and 5.31-fold by these PDN. In particular, the oral bioavailability of these PDN was significantly improved 3.0, 4.1, 5.4 and 10.4 folds compared with the free drug suspension. The enhanced cellular uptake and oral bioavailability were correlated with the characters of involved surfactants and the particle size of PDN. CONCLUSIONS: Thereby, the directed self-assembled nanoparticles could provide a new strategy for enhancing the oral delivery of hydrophobic drugs.
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Anticolesterolemiantes/administração & dosagem , Portadores de Fármacos/química , Nanopartículas/química , Probucol/administração & dosagem , Administração Oral , Animais , Anticolesterolemiantes/farmacocinética , Disponibilidade Biológica , Células CACO-2 , Humanos , Masculino , Tamanho da Partícula , Polietilenoglicóis/química , Polissorbatos/química , Probucol/farmacocinética , Ratos Sprague-Dawley , Tensoativos/química , Vitamina E/análogos & derivados , Vitamina E/químicaRESUMO
Multidrug resistance (MDR) is one of the main causes leading to the failure in cancer treatment. Differential proteins between esophageal squamous cell carcinoma (ESCC) cell line EC9706 and its cisdiamminedichloroplatinum (CDDP)-resistant subline EC9706/CDDP revealed by quantitative analysis may provide deeper insights into the molecular mechanisms of MDR implicated in ESCC. EC9706/CDDP was generated by exposure of its parental sensitive EC9706 to a step-wise increase of CDDP concentration during EC9706 cultivation. The stable isotope labeling with amino acids in cell culture (SILAC) was used to label EC9706 and EC9706/CDDP with heavy and light medium, separately. Mixed peptides derived from EC9706 and EC9706/CDDP were analyzed by high performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS/MS) and subsequently subjected to bioinformatics analysis to identify differential proteins between EC9706 and EC9706/CDDP. Compared to parental EC9706, EC9706/CDDP manifested phenotypes of slow proliferation, cell pleomorphology, atypia and increased resistant-index 3.23. Seventy-four differential proteins identified in the present study belongs to various families with multiple functions, such as cytoskeleton (20%), energy metabolism (11%), transcription regulation and DNA repair (11%), redox homeostasis (9.5%), protein biosynthesis and mRNA processing (12%), ribosome constituent (8.1%), molecular chaperone (8.1%), immunity/inflammation (5.4%), intracellular transport (5.4%) and nucleosome assembly (2.7%), which indicated that development of MDR is a complicated process involving dysregulation of multiple molecules and pathways. The data is of great value for in-depth elucidation of molecular mechanisms of the MDR implicated in ESCC and may represent potential molecular targets for future therapeutic development.
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Carcinoma de Células Escamosas/metabolismo , Cisplatino/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Neoplasias Esofágicas/metabolismo , Proteoma/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Neoplasias Esofágicas/patologia , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Oxirredutases Intramoleculares/metabolismo , Marcação por Isótopo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Proteômica , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Tiorredoxinas/metabolismoRESUMO
Radial glial cells are stem cells that play an important role in neuronal migration and proliferation in the developing brain. However, how radial glial cells contribute to the lamination of the cerebellar cortex is not well understood. We therefore used immunohistochemistry and BrdU labeling to follow radial glial cell differentiation, cell migration and cerebellar cortex development in mice from embryonic day 8 to postnatal day 180. We report that radial glial cells represent the stem cell population of the neuroepithelium of the neural tube, and act as progenitors for both neurons and neuroglia. In addition, radial glial cells not only give rise to the principal cells of the cerebellar cortex, the Purkinje and granule cells, but they also provide a scaffold for the migration of these cells. We conclude that radial glial cells play a pivotal role in establishing the laminar structure of the cerebellar cortex.
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Córtex Cerebelar/embriologia , Córtex Cerebelar/crescimento & desenvolvimento , Células-Tronco Neurais/fisiologia , Neurogênese/fisiologia , Neuroglia/fisiologia , Neurônios/fisiologia , Animais , Animais Recém-Nascidos , Diferenciação Celular/fisiologia , Córtex Cerebelar/citologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/transplante , Neuroglia/transplante , Neurônios/citologia , Migração Transcelular de Célula/fisiologiaRESUMO
BACKGROUND: The aim was to establish and characterize adriamycin (ADM)-resistant cell lines. MATERIAL/METHODS: Two cell lines, named Saos-2/ADM1 and Saos-2/ADM4, resistant to ADM, were established after 167 days. RESULTS: The resistance indices of methotrexate for the Saos-2/ADM1 and Saos-2/ADM4 cell lines to ADM were 49.8 and 74.6 times higher, respectively, than that of Saos-2. The two cells lines had resistance to MTX, IFO, EPI, THP, and PTX, while the cells were found to remain sensitive to cisplatin. Disordered and coenocytic structure were observed via microscopy. CONCLUSIONS: This is the first report on ADM-resistant cells based on clinical peak doses in serum. MDR1 and MRP genes are involved in the resistance of cell lines to ADM, which are invaluable tools to study the resistance of anticancer drugs and to find the means to revert the resistance.
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Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Osteossarcoma/metabolismo , Proliferação de Células , Cisplatino/farmacologia , Citometria de Fluxo/métodos , Humanos , Concentração Inibidora 50 , Metotrexato/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologiaRESUMO
The title compound, [Mn(C(8)H(7)N(3))(3)](2)[SiMo(12)O(40)]·6H(2)O, consists of an [SiMo(12)O(40)](4-) heteropolyanion, lying on a centre of inversion, and a complex [Mn(C(8)H(7)N(3))(3)](4+) cation. The Mn(II) atom of the cation is hexa-coordinated in a distorted octa-hedral geometry by six N atoms from three chelating 3-(2-pyrid-yl)pyrazole ligands. In the heteropolyanion, the four O atoms of the tetra-hedral SiO(4) group each half-occupy eight sites due to Si lying on the centre of inversion. N-Hâ¯O and O-Hâ¯O hydrogen bonding mediated by the water mol-ecules leads to a consolidation of the structure.