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1.
Chemistry ; 30(24): e202304056, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38379208

RESUMO

3-Indole-3-one is a key intermediate in the synthesis of many drugs and plays an important role in synthetic chemistry and biochemistry. A new method for synthesizing trifluoromethylated 3-indoleketones by Pd(0)-catalyzed carbonylation was introduced. In the absence of additives, 1-chloro-3,3,3-trifluoropropyl (an inexpensive and environmentally friendly synthetic block of trifluoromethyl) reacts with indole and carbon monoxide to generate trifluoromethylindole ketones with good yields, regioselectivity, and chemical selectivity; furthermore, the products exhibit strong resistance to basic functional groups, such as alkynes, aldehydes, and esters. In addition to the conversion of indole compounds into corresponding products, pyrrole and heteroindole may be suitable for corresponding chemical transformations. This study provides a synthetic method for the further construction of trifluoromethylated 3-indole ketones.

2.
J Appl Toxicol ; 41(4): 561-571, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33058278

RESUMO

The presence of metal ions, such as titanium (Ti) ions, is toxic to adjacent tissues of implants. Indeed, Ti ions may induce an inflammatory response through the NF-κB pathway, thus causing damage to soft and hard tissues. The involvement of Yes-associated protein (YAP), a key factor of the Hippo pathway, in an immuno-inflammatory response has been confirmed, whereas its role in Ti ion-mediated inflammation has not been elucidated. Therefore, this study aimed to investigate the role of signal crosstalk between the Hippo/YAP and NF-κB signaling pathways in the pro-inflammatory effect of Ti ions on macrophages. In our work, RAW264.7 cells were cocultured with Ti ions. The migration capacity of macrophages under Ti ion exposure was measured by transwell assay. Western blot analysis was used to detect the expressions of related proteins. Polymerase chain reaction was used to evaluate the expression of pro-inflammatory cytokines. The nucleus translocation of YAP and P65 was visualized and analyzed via immunofluorescence staining. The results showed that the migration of macrophages was promoted under Ti ion exposure. Ten parts per million Ti ions induced nuclear expression of YAP and activated the NF-κB pathway, which finally upregulated the expression of pro-inflammatory cytokines in macrophages. Moreover, the inhibition of the NF-κB pathway rescued the reduction of YAP expression under Ti ion exposure. Most importantly, the overexpression of YAP exacerbated the inflammatory response mediated by Ti ions through the NF-κB pathway. In summary, this study explored the mechanism of Hippo-YAP/NF-κB pathway crosstalk involved in the regulation of macrophage behaviors under Ti ion exposure.


Assuntos
Via de Sinalização Hippo/efeitos dos fármacos , Via de Sinalização Hippo/genética , Mediadores da Inflamação/metabolismo , Inflamação/etiologia , Inflamação/genética , Macrófagos/efeitos dos fármacos , Titânio/toxicidade , Animais , Proliferação de Células/efeitos dos fármacos , Camundongos , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
3.
Clin Oral Implants Res ; 30(10): 1038-1048, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31348555

RESUMO

OBJECTIVE: This study aims to investigate the influence of fluoride exposure on implant osseointegration. METHODS: A total of 24 male New Zealand white rabbits were randomly divided into the control group and the fluoride exposure group. Rabbits in the control group were fed with tap water, while those in the fluoride exposure group were given 200 mg/L sodium fluoride solution. After 2-month feeding, implants were inserted into the extraction socket immediately after extraction of rabbit mandibular anterior teeth. Four rabbits in each group were sacrificed to collect the implants samples at 1, 2, and 3 months post-implantation, respectively. Radiographic and histomorphometry examinations were performed to evaluate the condition of implant osseointegration. RESULTS: Bone volume around the implants increased in a time-dependent manner in both groups. Micro-CT images illustrated that the bone mineral density (BMD) in the fluoride exposure group was significantly lower than that in the control group after implantation for 2 and 3 months. The bone-implant contact ratio (BIC) in the fluoride exposure group was much lower than that of the control group at 3 months post-implantation according to histomorphometry examination. CONCLUSIONS: In rabbit animal model, high fluoride exposure affected the quality of bone surrounding the implant and significantly reduced bone integration of the implant, especially in the late stage of osseointegration.


Assuntos
Implantes Dentários , Osseointegração , Animais , Fluoretos , Masculino , Coelhos , Titânio , Microtomografia por Raio-X
4.
J Nanobiotechnology ; 17(1): 55, 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30992009

RESUMO

Titanium (Ti) and its alloys as bio-implants have excellent biocompatibilities and osteogenic properties after modification of chemical composition and topography via various methods. The corrosion resistance of these modified materials is of great importance for changing oral system, while few researches have reported this point. Recently, oxidative corrosion induced by cellular metabolites has been well concerned. In this study, we explored the corrosion behaviors of four common materials (commercially pure Ti, cp-Ti; Sandblasting and acid etching-modified Ti, Ti-SLA; nanowires-modified Ti, Ti-NW; and zinc-containing nanowires-modified Ti, Ti-NW-Zn) with excellent biocompatibilities and osteogenic capacities under the macrophages induced-oxidizing microenvironment. The results showed that the materials immersed into a high oxidizing environment were more vulnerable to corrode. Meanwhile, different surfaces also showed various corrosion susceptibilities under oxidizing condition. Samples embed with zinc element exhibited more excellent corrosion resistance compared with other three surfaces exposure to excessive H2O2. Besides, we found that zinc-decorated Ti surfaces inhibited the adhesion and proliferation of macrophages on its surface and induced the M2 states of macrophages to better healing and tissue reconstruction. Most importantly, zinc-decorated Ti surfaces markedly increased the expressions of antioxidant enzyme relative genes in macrophages. It improved the oxidation microenvironment around the materials and further protected their properties. In summary, our results demonstrated that Ti-NW-Zn surfaces not only provided excellent corrosion resistance properties, but also inhibited the adhesion of macrophages. These aspects were necessary for maintaining osseointegration capacity and enhancing the corrosion resistance of Ti in numerous medical applications, particularly in dentistry.


Assuntos
Peróxido de Hidrogênio/química , Nanofios/química , Titânio/química , Zinco/química , Animais , Materiais Biocompatíveis , Adesão Celular , Linhagem Celular , Proliferação de Células , Corrosão , Implantes Dentários , Macrófagos/metabolismo , Camundongos , Oxirredução , Propriedades de Superfície
5.
J Appl Toxicol ; 38(6): 824-833, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29377205

RESUMO

Titanium (Ti) and its corresponding alloys have been widely applied in dental and orthopedic implants. Owing to abrasion and corrosion of implants in the unfavorable electrolytic aqueous environment of the host body, Ti ions could be released from implants and accumulated in local tissues. Recent studies have found that excessive Ti ions were toxic to osteoblasts in adjacent bone tissues and subsequently influenced long-term effects on implant prostheses. However, the potential molecular mechanisms underlying the damage to osteoblasts induced by Ti ions remained unclear. Hippo signaling has been confirmed to be involved in organ size and tissue regeneration in many organs, while its roles in osteoblasts differentiation and bone repair remained elusive. Therefore, we hypothesize that YAP, a regulator of Hippo pathway, inhibited osteoblast growth, skeletal development and bone repair, as well as excessive Ti ions promoted the progression of YAP activation. This study aimed to explore the role of Hippo/YAP signaling pathway in the biotoxicity effect of Ti ions on osteoblast behaviors. Here, we confirmed that 10 ppm Ti ions, a minimum concentration gradient previously reported that was capable of suppressing osteoblasts growth, induced nuclear expression of YAP in osteoblasts in our study. Furthermore, 10 ppm Ti ion-induced YAP activation was found to downregulate osteogenic differentiation of MC3T3-E1 cells. Most importantly, the hypothesis we proposed that knockdown of YAP did reverse the inhibitory effect of 10 ppm Ti ions on osteogenesis has been verified. Taken together, our work provides insights into the mechanism of which YAP is involved in regulating osteoblast behaviors under the effect of Ti ions, which may help to develop therapeutic applications for Ti implant failures and peri-implantitis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Osteoblastos/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Titânio/toxicidade , Células 3T3 , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteínas de Ciclo Celular/genética , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica , Via de Sinalização Hippo , Camundongos , Osteoblastos/metabolismo , Osteoblastos/patologia , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Fosforilação , Proteínas de Sinalização YAP
6.
iScience ; 27(6): 110127, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38966571

RESUMO

Identifying the atlas of immune cells from coronary sinus circulation (CSC) of patients with persistent atrial fibrillation (PerAF) may provide new insights into the role of immune cells in the progression of AF. Single-cell sequencing revealed substantial alterations in immune cells from CSCs of patients with PerAF, especially a markedly elevated abundance of T cells, after which we identified a T cell subset: FGFBP2(+)TRDC(-)CD4(-) T cells (Ftc-T cells), which can promote the proliferation of cardiac fibroblasts (CFs),and the proportion of Ftc-T had a positive linear with AF recurrence post catheter ablation (CA). Moreover, IFI27 was found to be highly enriched in Ftc-T cells and promoted CFs proliferation and collagen expression. Altogether, our findings represent a unique resource providing in-depth insights into the heterogeneity of the immune cell from CSC of patients with PerAF and highlight the potential role of Ftc-T cells and IFI27 for AF progression.

7.
ACS Omega ; 8(7): 7128-7134, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36844566

RESUMO

Amide compounds are important organic compounds, which play an important role in biomedical chemistry, materials science, life science, and other fields. The synthesis of α-CF3 amides, especially compounds containing 3-(trifluoromethyl)-1,3,4,5-tetrahydro-2H-benzo[b][1,4]diazepine-2-one, has long been a challenge due to the tensile properties and instability of the rings. Here, we report an example of palladium-catalyzed carbonylation of CF3-containing olefin to form α-CF3 acrylamide. By controlling the ligands, we can get different amide compounds as products. This method has good substrate adaptability and functional group tolerance.

8.
Eur J Pharmacol ; 961: 176167, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37939994

RESUMO

BACKGROUND: Recent evidence revealed that glucose fluctuation might be more likely to cause arrhythmia than persistent hyperglycemia, whereas its mechanisms were elusive. We aimed to investigate the effect of glucose fluctuation on the occurrence of ventricular arrhythmia and its mechanism. METHODS: Streptozotocin (STZ) induced diabetic rats were randomized to five groups: the controlled blood glucose (C-STZ) group, uncontrolled blood glucose (U-STZ) group, fluctuated blood glucose (GF-STZ) group, and GF-STZ rats with 100 mg/kg Tempol (GF-STZ + Tempol) group or with 5 mg/kg KN93 (GF-STZ + KN93) group. Six weeks later, the susceptibility of ventricular arrhythmias and the electrophysiological dysfunctions of ventricular myocytes were evaluated using electrocardiogram and patch-clamp technique, respectively. The levels of reactive oxygen species (ROS) and oxidized CaMKII (ox-CaMKII) were determined by fluorescence assay and Western blot, respectively. Neonatal rat cardiomyocytes and H9C2 cells in vitro were used to explore the underlying mechanisms. RESULTS: The induction rate of ventricular arrhythmias was 10%, 55%, and 90% in C-STZ group, U-STZ group, and GF-STZ group, respectively (P < 0.05). The electrophysiological dysfunctions of ventricular myocytes, including action potential duration at repolarization of 90% (APD90), APD90 short-term variability (APD90-STV), late sodium current (INa-L), early after depolarization (EAD) and delayed after depolarizations (DAD), as well as the levels of ROS and ox-CaMKII, were significantly increased in GF-STZ group. In vivo and ex vivo, inhibition of ROS or ox-CaMKII reversed these effects. Inhibition of INa-L also significantly alleviated the electrophysiological dysfunctions. In vitro, inhibition of ROS increase could significantly decrease the ox-CaMKII activation induced by glucose fluctuations. CONCLUSIONS: Glucose fluctuations aggravated the INa-L induced ventricular arrhythmias though the activation of ROS/CaMKII pathway.


Assuntos
Diabetes Mellitus Experimental , Glucose , Animais , Ratos , Potenciais de Ação , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/metabolismo , Glicemia/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Diabetes Mellitus Experimental/metabolismo , Glucose/metabolismo , Miócitos Cardíacos , Espécies Reativas de Oxigênio/metabolismo , Sódio/metabolismo
9.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 7): m896, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22807738

RESUMO

In the title complex, [La(C7H4BrO3)Cl2(C12H8N2)](n), the La(III) ion is eight-coordinated by two carboxyl-ate O atoms from two 5-bromo-salicylate ligands, two N atoms from a chelating 1,10-phenanthroline ligand and four bridging Cl atoms in a distorted square-anti-prismatic geometry. The La(III) ions are linked by bridging carboxyl-ate groups and chloride anions into a chain along [100]. An intra-molecular O-H⋯O hydrogen bond is formed in the 5-bromo-salicylate ligand. π-π inter-actions between the pyridine and benzene rings and between the benzene rings are observed [centroid-centroid distances = 3.794 (5) and 3.804 (4) Å].

10.
Front Bioeng Biotechnol ; 10: 848769, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35528211

RESUMO

Zinc-modified titanium materials have been widely applied in oral implants. Among them, our previous studies have also successfully prepared a novel acid-etched microstructured titanium surface modified with zinc-containing nanowires (Ti-NW-Zn) and proved its excellent biocompatibility. It is well known that the functional regulation between angiogenesis and osteogenesis is of great importance for bone remodeling around implants. However, there are few reports concerning the biological safety of zinc ions released from materials and the appropriate concentration of released zinc ions which was more conducive to angiogenesis and bone regeneration. In this study, we investigated the effects of zinc ions released from Ti-NW-Zn surfaces on angiogenesis and osteogenesis using the zebrafish model and revealed the relationship between angiogenesis and osteogenesis via HUVECs and MC3T3-E1s in vitro. We found that the zinc ions released from Ti-NW-Zn surfaces, with a concentration lower than median lethal concentrations (LCs) of zebrafish, were biologically safe and promote osteogenesis and angiogenesis in vivo. Moreover, the proper concentration of zinc ions could induce the proliferation of HUVECs and osteogenic differentiation. The positive effects of the appropriate concentration of zinc ions on osteoblast behaviors might be regulated by activating the MAPK/ERK signaling pathway. These aspects may provide new sights into the mechanisms underlying zinc-modified titanium surfaces between osteogenesis and angiogenesis, to lay the foundation for further improving the materials, meanwhile, promoting the applications in dentistry.

11.
Zhonghua Yan Ke Za Zhi ; 47(5): 416-22, 2011 May.
Artigo em Zh | MEDLINE | ID: mdl-21756743

RESUMO

OBJECTIVE: To explore the morphological characteristics on cornea in patients with vernal keratoconjunctivitis (VKC) by the application of in vivo laser scanning confocal microscopy (LSCM). METHODS: The experimental design was retrospective observation case series (case control study). Twenty-six patients, each diagnosed as bilateral VKC, were enrolled in the study, among which 13 were tarsal form, 5 were bulbar form and the rest were mixed form. Nine patients had the clinical course less than one year, eight subjects longer than three years, and the rest between them. Another twenty-six healthy volunteers with matching age and gender were selected as normal control. All participants had their right eyes examined with the in vivo confocal microscopy (HRT II/RCM). Central cornea and superior peripheral cornea were chosen as the examination points. The images were recorded automatically and cellular density of each layer was analyzed by installed software. Software ImageJ was utilized to analyze the density, diameter, branch number and tortuosity of subbasal nerve fiber in VKC patients. Independent t test was performed to assess the differences on cellular density between VKC patients and normal control, as well as those between central and peripheral cornea in VKC patients. Fisher chi-square test was used to compare the infiltration rate of Langerhans cells in corneal epithelium between VKC patients and controls. ANOVA was applied to assess the differences in cellular density among three subtypes, as well as among different duration of VKC. Independent t-test and chi-square test were applied to analyze the parameters of subbasal nerve fiber. RESULTS: The morphological changes in cornea included the absence of superficial hyperreflective polygonal epithelial cells, infiltration of Langerhans cells in and(or) underneath corneal epithelium and activation of keratocytes in anterior stroma. Corneal epithelium conjunctivalization and stromal neovascularization could be identified in patients with corneal neovascular epithelium. Longitudinal or oblique dark striae could be found in the posterior stroma in patients with complicated keratoconus. The density of epithelial cells at central and peripheral cornea in healthy controls were (6033.1 ± 998.7) cells/mm(2) and (6098.4 ± 298.3) cells/mm(2), while that in VKC patients were (5972.2 ± 1148.2) cells/mm(2) and (6178.5 ± 318.9) cells/mm(2) respectively, the differences being no statistical significant between them (t = 1.191, 1.011; P = 0.238, 0.318). However, it's found in VKC patients that cellular density at peripheral cornea was significantly higher than that at central area (t = 2.249, P = 0.03). The density of anterior stromal cells at central and peripheral cornea in healthy controls was (1001.4 ± 125.3) cells/mm(2) and (924.6 ± 201.4) cells/mm(2), while that in VKC patients was (1184.5 ± 115.3) cells/mm(2) and (1101.4 ± 151.1) cells/mm(2), the difference bearing no statistical significance (t = 6.617, 3.439; P = 0.001). The density of posterior stromal cells in normal subjects and VKC patients was (537.7 ± 42.6) cells/mm(2) and (548.7 ± 79.8) cells/mm(2), that of endothelial cells was (2985.7 ± 401.2) cells/mm(2) and (3021.5 ± 383.3) cells/mm(2), respectively, neither difference had statistical significance (t = 0.174, 1.112; P = 0.864, 0.282). Langerhans cell infiltration could be identified in 61.5% (16 cases) VKC patients, which was significantly higher than normal control (2 cases, 7.7%) (χ(2) = 12.49, P = 0.001). Furthermore, much intense Langerhans cells infiltration was found in bulbar form and mix form than tarsal form. (t = 6.617, P = 0.001). The density and diameter of subbasal nerve fiber in VKC patients decreased significantly than those in normal subjects, whereas the tortuosity increased significantly. CONCLUSIONS: The morphological changes of cornea in VKC patients mainly involve corneal epithelium, subbasal nerve fiber and anterior stroma. In vivo LSCM is helpful in discriminating the subtypes of VKC.


Assuntos
Conjuntivite Alérgica/patologia , Córnea/patologia , Microscopia Confocal , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Conjuntivite Alérgica/diagnóstico , Feminino , Humanos , Masculino , Estudos Retrospectivos , Adulto Jovem
12.
Zhonghua Yan Ke Za Zhi ; 47(6): 539-45, 2011 Jun.
Artigo em Zh | MEDLINE | ID: mdl-21914270

RESUMO

OBJECTIVE: To evaluate the effects of protein-free calf blood extract for recovery of corneal nerve after LASEK and LSEIK. METHODS: A prospective, randomized, control and double-blind study was carried out from January through February 2009 at Department of Ophthalmology, Eye Ear Nose and Throat Hospital of Fudan University. Forty-nine eyes of 25 patients who underwent LASEK were randomly divided into two groups. One group with 16 patients (32 eyes) was treated by protein-free calf blood extract eye gel which was defined as drug treated group and the other group with 9 patients (17 eyes) was not treated by protein-free calf blood extract eye gel which was defined as no drug treated group. Forty-four eyes of 23 patients who underwent LASIK were also randomly divided into two groups. One group with 13 patients (24 eyes) was treated by protein-free calf blood extract eye gel which was defined as drug treated group and the other group with 10 patients (20 eyes) was not treated by protein-free calf blood extract eye gel which was defined as no drug treated group. Protein-free calf blood extract eye gel was delivered in both drug treated groups 3 times per day for three months after surgery. Laser scanning confocal microscopic examinations were performed on 48 eyes in vivo. Central corneal sensitivity and tear break-up time (BUT) were tested on 93 eyes preoperatively and 1, 3, 6 months, and 1 year after surgery. The obtained dates in the study were analyzed using independent samples t-test, paired t-test and Mann-Whitney Test. RESULTS: The morphology observed by confocal microscope of sub-basal nerve fibers was not different between drug treated group and no drug treated group until the last follow up after LASIK or LASEK (Z = 0.0000, P = 1.00) and (Z = 0.0000, P = 1.00). Nerve fibers with interconnections were observed in drug treated group at 3 months after LASEK. The morphology of sub-basal nerve fibers had not recovered completely until 1 year after surgery. The central corneal sensitivity was better in drug treated group than in no drug treated group at 1 month after LASEK [(4.95 ± 0.84) µm, (3.62 ± 1.38) µm; t = 4.23, P < 0.01] and at 1 and 3 months after LASIK [(3.29 ± 1.40)µm, (2.35 ± 1.51) µm; t = 2.10, P < 0.05], [(4.31 ± 1.61) µm, (3.18 ± 1.62) µm; t = 2.31, P < 0.05]. At 6 months postoperatively, the central corneal sensitivity of both drug treated group and no drug treated group which underwent LASEK was not significantly different from pre-operation [(5.81 ± 0.35) µm; t = -1.26, P > 0.05], [(5.79 ± 0.36) µm; t = -0.70, P > 0.05]. At 6 months postoperatively, the central corneal sensitivity of drug treated group which underwent LASIK was not significantly different from pre-operation [(5.25 ± 0.91) µm; t = -1.87, P > 0.05]. No significant difference was seen in BUT between drug treated group and no drug treated group after LASEK or LASIK until 1 year after surgery [(8.13 ± 2.18) µm, (8.76 ± 1.64) µm; t = -0.90, P > 0.05], [(7.71 ± 2.14) µm, (7.45 ± 2.37) µm; t = 0.30, P > 0.05]. CONCLUSION: Protein-free calf blood extract could significantly promote the recovery of corneal nerve in the early period after LASEK and LASIK.


Assuntos
Córnea/inervação , Ceratectomia Subepitelial Assistida por Laser/métodos , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Extratos de Tecidos/uso terapêutico , Adolescente , Animais , Bovinos , Método Duplo-Cego , Feminino , Humanos , Masculino , Regeneração Nervosa , Período Pós-Operatório , Estudos Prospectivos , Adulto Jovem
13.
RSC Adv ; 11(22): 13152-13163, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35423842

RESUMO

The development of effective methods to promote the osseointegration of dental implants by surface modification is an area of intense research in dental materials science. Exogenous metal ions present in the implant and surface modifications are closely related to the bone metabolism around the implant. In the complex oral microenvironment, the release of metal ions caused by continuous corrosion of dental implants has an unfavorable impact on the surrounding tissue, and then affects osseointegration, leading to bad results such as loosening and falling off in the late stage of the implant. Besides, these ions can even be distributed in distant tissues and organs. Currently, surface modification techniques are being developed that involve different processing technologies including the introduction of exogenous metal ions with different properties onto the surface of implants to improve performance. However, most metal elements have some level of biological toxicity and can only be used within a safe concentration range to exert the optimum biological effects on recipients. In this paper, we review the adverse effects of metal ions on osseointegration and highlight the emerging applications for metal elements in improving the performance of dental implants.

14.
Mater Sci Eng C Mater Biol Appl ; 119: 111610, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33321654

RESUMO

Titanium (Ti) and alloys thereof are commonly utilized in biomedical settings owing to their desirable mechanical properties and good biocompatibility. However, when exposed to biological systems for extended periods of time, Ti still undergoes corrosion. In the present study, we therefore explore the impact of osteoclasts (OC) on the surface characteristics and corrosion of commercially pure Titanium (cpTi) in the context of lipopolysaccharide (LPS)-induced inflammation. We utilized tartrate resistant acidic phosphatase (TRAP) and fluorescence staining to assess OC properties, while scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), optical profilometer, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization tests, and inductively coupled plasma atomic emission spectrometry (ICP-AES) were used to evaluate metal microstructure, surface composition and roughness, electrochemical corrosion properties, and metal ion release. SEM findings demonstrated that the surface of cpTi exhibited micro-pitting as well as the presence of viable OCs. Correspondingly, cpTi that had been exposed to OCs exhibited reduced levels of Ti, oxygen, and oxides within the corroded regions relative to smooth Ti as measured via EDS and XPS. OC exposure was also associated with significant changes in cpTi surface roughness, a significant decrease in corrosion resistance, and a significant increase in the release of Ti ions into the surrounding medium. In summary, these findings indicate that OC culture on the surface of cpTi can directly corrode titanium and lead to the release of Ti ions.


Assuntos
Osteoclastos , Titânio , Corrosão , Teste de Materiais , Microscopia Eletrônica de Varredura , Propriedades de Superfície
15.
Zhonghua Yan Ke Za Zhi ; 46(1): 18-24, 2010 Jan.
Artigo em Zh | MEDLINE | ID: mdl-20388317

RESUMO

OBJECTIVE: To analyze the morphology on the ocular surface of severe alkali burns patients by in vivo laser scanning confocal microscopy. METHODS: This research was a retrospective observation case series. From February to November 2008 in Eye Ear Nose and Throat Hospital of Fudan University, 39 alkali burns patients who classified as III or IV according to Roper-Hall classification were enrolled in this study. They were divided into four groups according to the course of disease: A (less than 3 months), B (3 - 6 months), C (6 - 12 months) and D (over 12 months). In vivo laser scanning confocal microscopic examinations were performed on the injured cornea, the limbus and the bulbar conjunctiva and the images were recorded. The morphology of the injured cornea, the limbus and the bulbar conjunctiva was analyzed and the densities of the inflammatory cells and dendritic cells in the limbus were calculated. One-way analysis of variance was used to compare the means of the inflammatory cells and dendritic cells. Subsequently the data between two groups were analyzed by least significant difference. RESULTS: The corneal epitheliums of the patients in Group A manifested large irregular features with hyperreflective cytoplasm and hyporeflective nuclei, sometimes losing cell features. There were numerous small hyperreflective inflammatory cells in groups beneath the superficial epitheliums. Shallow corneal stroma was edema, and it was hard to discriminate the morphology of the stromal cells. Deep stromal cells were in the activated state. The images of the endothelial layer were unclear. In Group B and Group C, there were the same manifestation of the superficial epitheliums as the group A and it disappeared in Group D. The inflammatory cells beneath the superficial epitheliums reduced and some residual basal epitheliums and hyperreflective conjunctiva-like epitheliums were visible in Group B and Group C. In Group D, there were small oval tight-arranged cells with punctiform hyperreflective nuclei instead of normal corneal basal epitheliums. In Group B, it was still hard to discriminate the morphology of the shallow stroma cells. Deep stromal cells were still in the activated state. In Group C and Group D, corneal stroma was replaced by the fibrous tissues. The images of the endothelial layer were still unclear in the other groups. The Vogt palisades in the limbus of the severe alkali burns patients were destroyed in all groups. There were rich vascular nets in the limbus. The densities of the limbal inflammatory cells in four groups were (4023 +/- 343), (2975 +/- 246), (2652 +/- 375), (2679 +/- 299) cells/mm(2), respectively. Significant difference in inflammatory cell density was found among groups (F = 40.001, P = 0.000). The densities of the limbal dendritic cells in four groups were (106 +/- 19), (132 +/- 35), (141 +/- 26), (98 +/- 24) cells/mm(2), respectively. Significant difference in dendritic cell density was found among groups (F = 8.053, P = 0.000). When the injured area of the conjunctiva was limited, it was hard to discriminate the morphology of the conjunctival epitheliums in both Group A and Group B. Numerous inflammatory cells infiltrated in the conjunctival lamina propria and goblet cells were invisible. In Group C and Group D, the conjunctival epitheliums were almost normal. There were still some inflammatory cells and dendritic cells in the conjunctival lamina propria, and there were residual goblet cells visible in parts of the patients. When the injured area of the conjunctiva was large, the conjunctivas in four groups displayed hyperreflective stripe fibrous tissues instead of normal conjunctival epitheliums. CONCLUSIONS: The application of laser scanning confocal microscopy indicates that there is much difference on the cellular morphology of the ocular surface of severe alkali burns patients among diverse courses of the disease. The technique is a useful tool to the observation on the ocular surface of severe alkali burns patients.


Assuntos
Queimaduras Químicas/patologia , Queimaduras Oculares/patologia , Microscopia Confocal , Adolescente , Adulto , Túnica Conjuntiva/patologia , Epitélio Corneano/patologia , Humanos , Limbo da Córnea/patologia , Masculino , Microscopia Confocal/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
16.
Mol Med Rep ; 22(6): 4792-4800, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33173964

RESUMO

The oral cavity is a complex environment that is constantly undergoing remodeling. This provides a favorable electrolytic aqueous condition, which causes the corrosion of titanium implants and the release of titanium (Ti) ions. The accumulation of Ti ions in the peri­implant tissues may affect the osteogenesis process. Therefore, the present study aimed to investigate the possible effects of Ti ions on osteoblast physiology and its underlying mechanism, specifically the MAPK/JNK signaling pathway. In the present study, MC3T3­E1 osteoblasts were cultured the medium containing 10 ppm Ti ions. Confocal laser scanning microscopy was used to analyze cell morphology and adhesion. Alkaline phosphatase (ALP) activity assay and western blotting were performed to evaluate the expression of proteins associated with osteogenesis such as Runx2 and Osterix. Nuclear translocation of JNK, a key factor of the MAPK signaling pathway, was visualized and analyzed using immunofluorescence staining. The results showed that 10 ppm Ti ions exerted negative effects on the biological behaviors of MC3T3­E1 cells, which exhibited reduced adhesion, ALP activity and osteogenic differentiation. It was also found that 10 ppm Ti ions activated the MAPK/JNK signaling pathway by promoting the nuclear translocation of JNK via phosphorylation. In addition, the inhibitory effects of 10 ppm Ti ions on MC3T3­E1 cells was found to be reversed by the JNK inhibitor SP600125. In conclusion, the preset study suggests that the MAPK/JNK signaling pathway serves a key role in the molecular mechanism underlying the changes in osteoblast behavior following Ti ion exposure. These findings may serve as a valuable reference point for the further in­depth exploration of peri­implant bone loss.


Assuntos
Osteoblastos/metabolismo , Titânio/efeitos adversos , Células 3T3 , Fosfatase Alcalina/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Corrosão , Íons/efeitos adversos , Íons/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Propriedades de Superfície , Titânio/farmacologia
17.
Zhonghua Yan Ke Za Zhi ; 45(4): 344-9, 2009 Apr.
Artigo em Zh | MEDLINE | ID: mdl-19575968

RESUMO

OBJECTIVE: To analyze the morphology of human bulbar conjunctiva by in vivo laser scanning confocal microscopy. METHODS: This research was a cross-sectional study. From February to July 2008, 50 eyes of 50 healthy subjects were enrolled in this study. They had no history of ocular trauma, infection or contact lens wear and had no found after routine slit-lamp examinations. In vivo laser scanning confocal microscopic examinations were performed on the superior, inferior, nasal and temporal bulbar conjunctiva and the images were recorded. The morphology of bulbar conjunctiva was analyzed and the density of epithelial cells, dendritic cells and goblet cells were calculated. One-way analysis of variance (ANOVA) was used to compare the means of epithelial cell densities in different layers and goblet cell densities in different positions. Subsequently the datum between two groups were analyzed by least significant difference (LSD). RESULTS: Superficial epithelial cells of bulbar conjunctiva were characterized as large loose-arranged cells with a hyporeflective nucleus. The mean density is (1643 +/- 206) cells/mm(2). Intermediate epithelial cells were captured with features of oval small tight-arranged cells with a punctiform hyperreflective nucleus. The mean density is (4693 +/- 228) cells/mm(2). Basal epithelial cells appeared to be polygonal and regular-arranged within hyperreflective cell borders. The mean density is (4420 +/- 230) cells/mm(2). There was a significant difference among three kinds of conjunctival epithelium (F = 1160.312, P = 0.000). The presumed goblet cell was defined as a large hyperreflective oval-shaped cell with relatively homogeneous brightness, crowded in groups or mainly dispersed. The mean density is (432 +/- 72) cells/mm(2). The dendritic cell appeared to be hyperreflective corpuscular particles with dendritic processes scattered among conjunctival epithelial cells. The mean density is (22 +/- 25) cells/mm(2). The basement membrane, a prominent hyperreflective band, separated epithelial cells from subepithelial structure. Bulbar conjunctival substantia propria, beneath the basement membrane, was mainly composed of highly vascularized, loose connective tissues which were irregularly arranged fibers or a network of fibers, punctiform hyperreflective immune cells and sharp flows of blood vessels. CONCLUSION: In vivo laser scanning confocal microscopy is a useful tool in the analysis of the bulbar conjunctival morphology, which provided a fast and noninvasive method for the diagnosis of ocular surface diseases.


Assuntos
Túnica Conjuntiva/anatomia & histologia , Microscopia Confocal/métodos , Adolescente , Adulto , Idoso , Túnica Conjuntiva/citologia , Estudos Transversais , Células Dendríticas/ultraestrutura , Células Epiteliais/ultraestrutura , Feminino , Células Caliciformes/ultraestrutura , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
18.
Zhonghua Xin Xue Guan Bing Za Zhi ; 37(9): 790-3, 2009 Sep.
Artigo em Zh | MEDLINE | ID: mdl-20128375

RESUMO

OBJECTIVE: To detect gene mutations associated with hypertrophic cardiomyopathy (HCM) in Chinese patients and possible correlations between genotype and phenotype. METHODS: Twenty-one unrelated patients with hypertrophic cardiomyopathy were studied. The clinical data including symptoms, physical examination, echocardiography and electrocardiography were collected. The full ecoding exons of cardiac myosin-binding protein C gene (cMYBPC3) were amplified with PCR and the products were sequenced. RESULTS: Two mutations were identified in probands from two families. One mutation was frame shift mutation Pro1208fs in the exon 32 of the cMYBPC3 gene. Pro1208fs mutation was identified in a 59 years old female patient with familial hypertrophic cardiomyopathy. Symptom onset was late and a favorable clinical course was evidenced in this patient. Another mutation was missence mutation Gly507Arg in the exon 17 of the MYBPC3 gene identified in a 24 years old male patient. Diffuse thickness of left ventricular wall, impaired diastolic function and enlarged left atria were evidenced in echocardiography. No mutation was identified in the 80 control healthy individuals. CONCLUSION: cMYBPC3 might be the disease-causing genes in Chinese patients with hypertrophic cardiomyopathy.


Assuntos
Cardiomiopatia Hipertrófica/genética , Proteínas de Transporte/genética , Mutação , Adolescente , Adulto , Idoso , Povo Asiático/genética , Estudos de Casos e Controles , Éxons , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Adulto Jovem
19.
RSC Adv ; 9(32): 18589-18598, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35515248

RESUMO

Objective: This study aims to investigate the adsorption of low density lipoprotein (LDL) on a titanium surface and to explore its effect on osteoblast behaviors. Materials and methods: LDL adsorption on a titanium surface was analyzed using LDL assay and X-ray photoelectron spectroscopy (XPS). Physical properties, including topography, surface roughness and wettability of a control smooth titanium surface and a LDL pre-adsorbed titanium surface, were assessed. Subsequently, the adhesion, proliferation and differentiation abilities of MC3T3-E1 cells (an osteoblast-like cell line) on the surfaces of control titanium and LDL pre-adsorbed titanium were investigated. Results: LDL assay and XPS confirmed LDL adsorption on the titanium surface. The maximum adsorption of LDL on the titanium surfaces was observed after 150 minutes of incubation. In comparison with the control smooth titanium surface, the roughness and hydrophilicity of the LDL pre-adsorbed titanium surface were significantly altered. Furthermore, in vitro studies demonstrated that LDL adsorption obviously attenuated the adhesion, proliferation and differentiation of MC3T3-E1 cells on the titanium surface. Conclusion: LDL could adsorb on a titanium surface. Meanwhile, LDL adsorption changed the characteristics of the titanium surface, which, in turn, negatively regulated osteoblast behaviors.

20.
J Mol Med (Berl) ; 97(7): 1003-1017, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31055605

RESUMO

Titanium is widely used in implant materials, while excessive fluoride may have negative effects on the osseointegration between the titanium and osteoblasts. Although the underlying mechanisms are still not clear, the mitogen-activated protein kinase (MAPK) or Yes-associated protein (YAP) signaling pathways are thought to be involved. This study evaluated the role of Hippo/YAP and MAPK signaling pathway in osteoblast behaviors under excessive fluoride exposure in vitro and in vivo. Commercially pure Ti (cp-Ti) samples were exposed to fluoride (0, 0.1, and 1.0 mM NaF) for 7 days. Cell adhesion was observed using a laser scanning confocal microscope. Cell viability and apoptosis were evaluated by CCK-8 assay and flow cytometry, respectively. The expressions of osteoblast markers and key molecules in MAPK and YAP pathway were detected by Western blot. In vivo studies were evaluated by histology methods in C57/BL6 mice model. Our results showed that 1.0 mM NaF destroyed the passivation film on cp-Ti surface, which further inhibited the osteoblast adhesion and spreading. Meanwhile, compared to other groups, 1.0 mM NaF led to a remarkable reduction in cell viability (P < 0.05), as well as increased apoptosis (P < 0.05) and downregulation of osteogenesis protein expression (P < 0.05). MAPK and YAP signaling pathways were also activated under 1.0 mM NaF exposure, and JNK seemed to regulate YAP phosphorylation in response to NaF impacts on osteoblasts. In vivo fluorosis mouse model further indicated that 100 ppm NaF group (high fluoride group) increased bone resorption and inhibited the nuclear translocation of YAP. The osteoblast behaviors were negatively altered under excessive fluoride, and MAPK/JNK axis contributed to YAP signaling activation in regulating NaF-induced osteoblast behaviors. KEY MESSAGES: • Excessive fluoride inhibited osteoblast behaviors and bone formation. • YAP and MAPK signaling pathways were activated in osteoblasts under fluoride exposure. • Fluoride regulated osteoblast behaviors via the cross-talk between YAP and MAPK.


Assuntos
Fluoretos/farmacologia , Sistema de Sinalização das MAP Quinases , Osteoblastos/metabolismo , Proteínas Quinases/metabolismo , Fatores de Transcrição/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Reabsorção Óssea/patologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Corrosão , Modelos Animais de Doenças , Fêmur/efeitos dos fármacos , Fêmur/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Propriedades de Superfície
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