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1.
Dent Mater ; 40(4): 716-727, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395738

RESUMO

OBJECTIVES: This study aimed to compare two types of bioactive additives which were strontium-containing fluorinated bioactive glass (SrBGF) or strontium-containing fluorapatite (SrFA) added to sol-gel derived glass ionomer cement (SGIC). The objective was to develop antibacterial and mineralisation properties, using bioactive additives, to minimize the occurrence of caries lesions in caries disease. METHODS: Synthesized SrBGF and SrFA nanoparticles were added to SGIC at 1 wt% concentration to improve antibacterial properties against S. mutans, promote remineralisation, and hASCs and hDPSCs viability. Surface roughness and ion-releasing behavior were also evaluated to clarify the effect on the materials. Antibacterial activity was measured via agar disc diffusion and bacterial adhesion. Remineralisation ability was assessed by applying the material to demineralised teeth and subjecting them to a 14-day pH cycle, followed by microCT and SEM-EDS analysis. RESULTS: The addition of SrFA into SGIC significantly improved its antibacterial property. SGIC modified with either SrBGF or SrFA additives could similarly induce apatite crystal precipitation onto demineralised dentin and increase dentin density, indicating its ability to remineralise dentin. Moreover, this study also showed that SGIC modified with SrBGF or SrFA additives had promising results on the in vitro cytotoxicity of hASC and hDPSC. SIGNIFICANT: SrFA has superior antibacterial property as compared to SrBGF while demonstrating equal remineralisation ability. Furthermore, the modified SGIC showed promising results in reducing the cytotoxicity of hASCs and hDPSCs, indicating its potential for managing caries.


Assuntos
Cárie Dentária , Fluoretos , Humanos , Fluoretos/farmacologia , Fluoretos/química , Cimentos de Ionômeros de Vidro/farmacologia , Cimentos de Ionômeros de Vidro/química , Estrôncio/farmacologia , Estrôncio/química , Antibacterianos/farmacologia , Antibacterianos/química , Apatitas/farmacologia , Cárie Dentária/terapia , Teste de Materiais
2.
Artigo em Inglês | MEDLINE | ID: mdl-37455847

RESUMO

Breast cancer recurrence continues to pose a major clinical problem, despite significant advancements in early diagnosis and an aggressive mode of treatment. This study aimed at investigating the anticancer activity of Oroxylum indicum extract (OIE) by assessing cell proliferation, cell migration, and angiogenesis in metastatic breast cancer MDA-MB-231 cell lines. This study also estimated the phytochemical profiles of OIE by LC-QTOF-MS. The extract was found to contain six identified flavonoid substances, and baicalein was the most abundant substance in the extract. Cell proliferation capacity was performed by cell counting kit-8 (CCK-8) and colony formation assays. The effect of OIE on cell migration was determined using wound healing and transwell assays. Meanwhile, MDA-MB-231-induced angiogenesis on chick chorioallantoic membrane (CAM) was applied to investigate the ex vivo antiangiogenesis activity of the extracts. OIE at concentrations lower than 600 µg/mL had no cytotoxic effects against MDA-MB-231 cells. OIE was found to inhibit the long-term colony formation ability of MDA-MB-231 cells in a concentration-dependent manner. Antimigration and antiangiogenesis activities were further investigated using noncytotoxic concentrations of OIE ranging from 25 to 150 µg/mL. OIE greatly reduced the migration of MDA-MB-231 breast cancer cells in a dose-dependent manner. OIE significantly suppressed the MDA-MB-231-induced angiogenesis, and there was no substantial toxic effect on natural angiogenesis. Interestingly, the concentration of OIE at 150 µg/mL was as practically potent as pazopanib, the positive anticancer drug, at 4.37 µg/mL in inhibiting MDA-MB-231 cell migration and angiogenesis induced by these cells. Therefore, the inhibitory effects of OIE in cell proliferation and cell migration, together with antiangiogenesis in MDA-MB-231 breast cancer cells, suggesting that OIE has the potential to be a novel adjunct candidate for breast cancer chemotherapeutic agents.

3.
J Int Med Res ; 49(2): 300060520976864, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33535865

RESUMO

OBJECTIVE: This study aimed to investigate the expression of O-linked glycoprotein glycans in tissue of patients with cholangiocarcinoma compared with adjacent normal tissue. METHODS: Sixty patients with cholangiocarcinoma were included in the study. Permethylated O-linked glycans from intrahepatic cholangiocarcinoma tissue and adjacent normal tissue were analyzed using nano-spray ionization-linear ion trap mass spectrometry. Histochemistry of peanut agglutinin lectin was used for detection and localization of galactose (Gal) 1, N-acetyl-galactosamine (GalNAc) 1. RESULTS: O-linked glycans from patients with cholangiocarcinoma were composed of di- to hexa-saccharides with a terminal galactose and sialic acids (N-acetylneuraminic acid [NeuAc]). A total of eight O-linked glycan structures were detected. Gal1GalNAc1 and Gal2 N-acetyl-glucosamine 1 GalNAc1 expression was significantly higher in tissue from patients with cholangiocarcinoma compared with adjacent normal tissue, while NeuAc1Gal1GalNAc1 expression was significantly lower. High Gal1GalNAc1 expression was significantly associated with the late stage of cholangiocarcinoma (stages II-IV), lymphatic invasion, and vascular invasion. CONCLUSION: Our study shows expression of O-linked glycans in progression of cholangiocarcinoma and highlights the association of Gal1GalNAc1 with lymphatic and vascular invasion of cholangiocarcinoma.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Ductos Biliares Intra-Hepáticos , Humanos , Fenótipo , Polissacarídeos
4.
Biomed Mater ; 15(5): 055038, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32217815

RESUMO

Injectable biphasic calcium phosphate bone cements (BCPCs) composed of ß-tricalcium phosphate (ß-TCP) and hydroxyapatite (HA) have been intensively investigated because of their high rate of biodegradation, bioactivity and osteoconductivity, which can be adjusted by changing the ratio between ß-TCP and HA phases after setting. The aim of this study was to evaluate the performance of 1 wt% chitosan fiber additive with biphasic calcium phosphate as an injectable bone cement both in vitro and in vivo. In vitro evaluation of compressive strength, degradation rate, morphology, and cell and alkaline phosphatase activities was done by comparison with bone cement without ß-TCP. The in vivo results for micro-CT scanning and histological examinations for three groups (control, BCPC and commercial biphasic calcium phosphate granules) were characterized and compared. After the addition of 20 wt% ß-TCP to calcium phosphate cement, the initial and final setting times of the sample were 3.92 min and 11.46 min, respectively, which were not significantly different from cement without ß-TCP. The degradation time of the BCPC material was longer than that of calcium phosphate cement alone. The healing process was significantly faster for BCPC than for the control and commercial product groups. Therefore, this is the first evidence that BCPC is an attractive option for bone surgery due to its faster stimulation of healing and faster degradation rate.


Assuntos
Cimentos Ósseos , Fosfatos de Cálcio/química , Quitosana/química , Força Compressiva , Células 3T3 , Animais , Materiais Biocompatíveis , Regeneração Óssea , Osso e Ossos/patologia , Adesão Celular , Diferenciação Celular , Proliferação de Células , Durapatita/química , Hidroxiapatitas , Técnicas In Vitro , Masculino , Camundongos , Osteoblastos/metabolismo , Tamanho da Partícula , Pós , Estudos Prospectivos , Coelhos , Difração de Raios X , Microtomografia por Raio-X
5.
Int J Mol Sci ; 20(12)2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31226809

RESUMO

Currently, human Wharton's jelly-derived mesenchymal stem cells (hWJ-MSCs) are an attractive source of stem cells for cell-based therapy, owing to their ability to undergo self-renewal and differentiate into all mesodermal, some neuroectodermal, and endodermal progenies, including hepatocytes. Herein, this study aimed to investigate the effects of sodium butyrate (NaBu), an epigenetic regulator that directly inhibits histone deacetylase, on hepatic endodermal lineage differentiation of hWJ-MSCs. NaBu, at 1 mM, optimally promoted endodermal differentiation of hWJ-MSCs, along with epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) supplementation (EGF + bFGF + 1 mM NaBu). CXCR4, HNF3ß, SOX17 (endodermal), and GATA6 (mesendodermal) mRNAs were also up-regulated (p < 0.001). Immunocytochemistry and a Western blot analysis of SOX17 and HNF3ß confirmed that the EGF + bFGF + 1 mM NaBu condition was appropriately pre-treated with hWJ-MSCs before hepatogenic differentiation. Furthermore, the hepatogenic medium + NaBu pre-treatment up-regulated hepatoblast (AFP and HNF3ß) and hepatic (CK18 and ALB) markers, and increased the proportion of mature hepatocyte functions, including G6P, C/EBPα, and CYP2B6 mRNAs, glycogen storage and urea secretion. The hepatogenic medium + NaBu in the pre-treatment step can induce hWJ-MSC differentiation toward endodermal, hepatoblastic, and hepatic lineages. Therefore, the hepatogenic medium + NaBu pre-treatment for differentiating hWJ-MSCs could represent an alternative protocol for cell-based therapy and drug screening in clinical applications.


Assuntos
Hepatócitos/citologia , Células-Tronco Mesenquimais/citologia , Geleia de Wharton/citologia , Animais , Ácido Butírico/farmacologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular/efeitos dos fármacos , Separação Celular , Células Cultivadas , Inibidores de Histona Desacetilases/farmacologia , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos
6.
J Med Assoc Thai ; 99 Suppl 7: S125-32, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-29901966

RESUMO

Background: Many researchers have been trying different methods for obtaining stem cells. Some studies have failed due to the growth of a tumor after stem cells transplantation. Several successful tries for getting stem cells or stem cell like cells: direct isolation from tissue, direct isolation from blood or fluids, iPS cells, small molecules induced stem cells. However, none have used real organ stimulation in the induction of a specific stem cell lineage. Objective: To induce a lineage specific hepatic stem cell using isolated embryonic organs. Material and Method: The embryonic stem cells were cultured through confluence. After observing several colonies formations, we put freshly isolated chicken embryonic hearts onto the colonies. After, at least, four days, we started looking for hepatic plate-like formations. Results: After several trials, we found that the chicken embryonic hearts, on day 4, could actually induce a hepatic cell fate for the mouse embryonic stem cells. We were able to show specific marker for early hepatic lineage such as the production of Albumin, AFP. When these cells were tested for a hepatocyte function, we found glycogen formation inside the cells. Conclusion: Isolated early embryonic chicken hearts are acceptable for inducing embryonic stem cells into the hepatic stem cell lineage.


Assuntos
Embrião de Galinha/citologia , Células-Tronco Embrionárias/citologia , Hepatócitos/citologia , Células-Tronco Embrionárias Murinas/citologia , Animais , Contagem de Células , Diferenciação Celular/fisiologia , Linhagem da Célula , Células Cultivadas , Embrião de Galinha/metabolismo , Galinhas , Células-Tronco Embrionárias/metabolismo , Hepatócitos/metabolismo , Células-Tronco Pluripotentes Induzidas , Camundongos , Modelos Animais , Células-Tronco Embrionárias Murinas/metabolismo
7.
Dig Dis Sci ; 60(12): 3669-80, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26173507

RESUMO

BACKGROUND: Because the molecular mechanisms of morphogenesis of the hepatic cord and sinus are unclear, we investigated the involvement of bone morphogenetic protein (BMP4) in hepatic sinusoid morphogenesis. METHODS: We used embryonic chicken livers, which develop rapidly, as our model, and investigated expression of BMP-related genes. BMP4 activity was manipulated by overexpressing BMP4 and its antagonist, noggin. RESULTS: During hepatic cord morphogenesis, BMP4 and its receptors are expressed in both peri-sinusoidal cells and hepatoblasts as the sinusoids form, whereas noggin is expressed transiently in peri-sinusoidal cells at early stages. Suppression of BMP activity with noggin overexpression disrupted normal hepatic sinusoid structure, leading to liver congestion, failure of fibronectin deposition, and markedly reduced numbers of peri-sinusoidal cells. However, overexpression of BMP did not change sinusoidal morphology but increased endothelial cell number. Noggin overexpression resulted in disrupted cord organization, and dilated sinusoidal space, eventually leading to increased apoptosis and failed hepatocyte differentiation. CONCLUSIONS: Our results show that proper BMP signaling mediates peri-sinusoidal cell-hepatoblast interactions during development; this is essential for hepatic cord organization among hepatoblasts, endothelium, and presumptive hepatic stellate cells.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas de Transporte/metabolismo , Células Estreladas do Fígado/fisiologia , Fígado/embriologia , Fígado/metabolismo , Células-Tronco Mesenquimais/fisiologia , Animais , Proteínas de Transporte/genética , Comunicação Celular , Embrião de Galinha , Regulação da Expressão Gênica no Desenvolvimento , Transdução de Sinais
8.
Anim Reprod Sci ; 136(1-2): 115-20, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23067865

RESUMO

Plasma leptin concentrations were investigated during the reproductive cycle in the native Thai chicken. The plasma leptin concentration was high during non-laying (0.69±0.15ng/ml), lowered to a minimum concentration during egg laying (0.07±0.02ng/ml), and gradually increased during egg incubation and rearing of the chicks (0.53±0.22 and 0.74±0.29ng/ml, respectively). However, the differences were not significant. Incubating chickens that were deprived of their nests for 3 weeks showed a significant decrease in plasma leptin concentrations (0.29±0.04ng/ml, P<0.05) compared to those of their corresponding incubating controls (0.77±0.08ng/ml). Similarly, plasma leptin concentration of chickens that were deprived of their chicks for 4 weeks was significantly lower (0.09±0.11ng/ml, P<0.05), when compared to those of chickens that rearing their chicks (0.71±0.18ng/ml). These findings taken together with the results that the low plasma leptin concentrations were observed in chickens having relatively greater ovary and oviduct weights led to the suggestion that circulating leptin concentrations are associated with the reproductive states of the birds, especially the ovarian activity (i.e. ovarian steroid hormone concentrations) in the native Thai chicken, a tropical and continuous breeding species.


Assuntos
Galinhas/fisiologia , Leptina/sangue , Reprodução/fisiologia , Animais , Peso Corporal/fisiologia , Feminino , Leptina/metabolismo , Masculino , Tamanho do Órgão/fisiologia , Ovário/anatomia & histologia , Ovário/fisiologia , Oviductos/anatomia & histologia , Oviductos/fisiologia
9.
Int J Dev Biol ; 56(9): 719-28, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23319347

RESUMO

The ephrin receptor (Eph) tyrosine kinases and their ephrin ligands are involved in morphogenesis during organ formation. We studied their role in feather morphogenesis, focusing on ephrin-B1 and its receptor EphB3. Early in feather development, ephrin-B1 mRNA and protein were found to be expressed in the dermal condensation, but not in the inter-bud mesenchyme. Later, in feather buds, expression was found in both the epithelium and mesenchyme. In the feather follicle, ephrin-B1 protein expression was found to be enriched in the feather filament epithelium and in the marginal plate which sets the boundary between the barb ridges. EphB3 mRNA was also expressed in epithelia. In the feather bud, its expression was restricted to the posterior bud. In the follicle, its expression formed a circle at the bud base which may set the boundary between bud and inter-bud domains. Perturbation with ephrin-B1/Fc altered feather primordia segregation and feather bud elongation. Analyses revealed that ephrin-B1/Fc caused three types of changes: blurred placode boundaries with loose dermal condensations, incomplete follicle invagination with less compact dermal papillae, and aberrant barb ridge patterning in feather filament morphogenesis. Thus, while ephrin-B1 suppression does not inhibit the initial emergence of a new epithelial domain, Eph/ephrin-B1 interaction is required for its proper completion. Consequently, we propose that interaction between ephrin-B1 and its receptor is involved in boundary stabilization during feather morphogenesis.


Assuntos
Efrina-B1/metabolismo , Plumas/embriologia , Receptor EphB3/metabolismo , Animais , Embrião de Galinha , Efrina-B1/genética , Epitélio/metabolismo , Plumas/metabolismo , Mesoderma/metabolismo , Morfogênese/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor EphB3/genética
10.
Science ; 305(5689): 1465-6, 2004 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-15353803

RESUMO

Beak shape is a classic example of evolutionary diversification. Beak development in chicken and duck was used to examine morphological variations among avian species. There is only one proliferative zone in the frontonasal mass of chickens, but two in ducks. These growth zones are associated with bone morphogenetic protein 4 (BMP4) activity. By "tinkering" with BMP4 in beak prominences, the shapes of the chicken beak can be modulated.


Assuntos
Bico/embriologia , Proteínas Morfogenéticas Ósseas/metabolismo , Embrião de Galinha , Patos/embriologia , Animais , Proteína Morfogenética Óssea 4 , Proteínas Morfogenéticas Ósseas/genética , Proteínas de Transporte , Divisão Celular , Galinhas/genética , Galinhas/metabolismo , Patos/genética , Patos/metabolismo , Técnicas de Transferência de Genes , Vetores Genéticos , Mesoderma/metabolismo , Morfogênese , Proteínas/genética , Proteínas/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Especificidade da Espécie
11.
Int J Dev Biol ; 48(2-3): 249-70, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15272390

RESUMO

Integuments form the boundary between an organism and the environment. The evolution of novel developmental mechanisms in integuments and appendages allows animals to live in diverse ecological environments. Here we focus on amniotes. The major achievement for reptile skin is an adaptation to the land with the formation of a successful barrier. The stratum corneum enables this barrier to prevent water loss from the skin and allowed amphibian / reptile ancestors to go onto the land. Overlapping scales and production of beta-keratins provide strong protection. Epidermal invagination led to the formation of avian feather and mammalian hair follicles in the dermis. Both adopted a proximal - distal growth mode which maintains endothermy. Feathers form hierarchical branches which produce the vane that makes flight possible. Recent discoveries of feathered dinosaurs in China inspire new thinking on the origin of feathers. In the laboratory, epithelial - mesenchymal recombinations and molecular mis-expressions were carried out to test the plasticity of epithelial organ formation. We review the work on the transformation of scales into feathers, conversion between barbs and rachis and the production of "chicken teeth". In mammals, tilting the balance of the BMP pathway in K14 noggin transgenic mice alters the number, size and phenotypes of different ectodermal organs, making investigators rethink the distinction between morpho-regulation and pathological changes. Models on the evolution of feathers and hairs from reptile integuments are discussed. A hypothetical Evo-Devo space where diverse integument appendages can be placed according to complex phenotypes and novel developmental mechanisms is presented.


Assuntos
Evolução Biológica , Crescimento e Desenvolvimento , Tegumento Comum/embriologia , Vertebrados/embriologia , Vertebrados/crescimento & desenvolvimento , Animais , Morfogênese
12.
Dev Biol ; 266(1): 109-22, 2004 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-14729482

RESUMO

During development and regeneration, new cells are added and incorporated to the liver parenchyma. Regulation of this process contributes to the final size and shape of the particular organs, including the liver. We identified the distribution of liver growth zones using an embryonic chicken model because of its accessibility to experimentation. Hepatocyte precursors were first generated all over the primordia surrounding the vitelline blood vessel at embryonic day 2 (E2), then became limited to the peripheral growth zones around E6. Differentiating daughter cells of the peripheral hepatocyte precursors were shown by DiI microinjection to be laid inward and were subsequently organized to form the hepatic architecture. At E8, hepatocyte precursor cells were further restricted to limited segments of the periphery, called localized growth zones (LoGZ). Adhesion and signaling molecules in the growth zone were studied. Among them, beta-catenin and Wnt 3a were highly enriched. We overexpressed constitutively active beta-catenin using replication competent avian sarcoma (RCAS) virus. Liver size increased about 3-fold with an expanded hepatocyte precursor cell population. In addition, blocking beta-catenin activity by either overexpression of dominant-negative LEF1 or overexpression of a secreted Wnt inhibitor Dickkopf (DKK) resulted in decreased liver size with altered liver shape. Our data suggest that (1) the duration of active growth zone activity modulates the size of the liver; (2) a shift in the position of the localized growth zone helps to shape the liver; and (3) beta-catenin/Wnt are involved in regulating growth zone activities during liver development.


Assuntos
Proteínas do Citoesqueleto/fisiologia , Fígado/embriologia , Proteínas Proto-Oncogênicas/fisiologia , Transativadores/fisiologia , Proteínas de Peixe-Zebra , Animais , Sequência de Bases , Embrião de Galinha , Primers do DNA , Genes Reporter , Imuno-Histoquímica , Luciferases/genética , Microinjeções , Morfogênese , Proteínas Wnt , beta Catenina
13.
J Invest Dermatol ; 120(1): 20-6, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12535194

RESUMO

Skin appendage formation represents a process of regulated new growth. Bromodeoxyuridine labeling of developing chicken skin demonstrated the presence of localized growth zones, which first promote appendage formation and then move within each appendage to produce specific shapes. Initially, cells proliferate all over the presumptive skin. During the placode stage they are organized to form periodic rings. At the short feather bud stage, the localized growth zones shifted to the posterior and then the distal bud. During the long bud stage, the localized growth zones descended through the flank region toward the feather collar (equivalent to the hair matrix). During feather branch formation, the localized growth zones were positioned periodically in the basilar layer to enhance branching of barb ridges. Wnts were expressed in a dynamic fashion during feather morphogenesis that coincided with the shifting localized growth zones positions. The expression pattern of Wnt 6 was examined and compared with other members of the Wnt pathway. Early in feather development Wnt 6 expression overlapped with the location of the localized growth zones. Its function was tested through misexpression studies. Ectopic Wnt 6 expression produced abnormal localized outgrowths from the skin appendages at either the base, the shaft, or the tip of the developing feathers. Later in feather filament morphogenesis, several Wnt markers were expressed in regions undergoing rearrangements and differentiation of barb ridge keratinocytes. These data suggest that skin appendages are built to specific shapes by adding new cells from well-positioned and controlled localized growth zones and that Wnt activity is involved in regulating such localized growth zone activity.


Assuntos
Proteínas do Citoesqueleto/fisiologia , Plumas/embriologia , Proteínas Proto-Oncogênicas/fisiologia , Transativadores/fisiologia , Proteínas de Peixe-Zebra , Animais , Embrião de Galinha , Receptores Frizzled , Morfogênese , Antígeno Nuclear de Célula em Proliferação/análise , Receptores Acoplados a Proteínas G , Receptores de Neurotransmissores/fisiologia , Proteínas Wnt , beta Catenina
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