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1.
Eur J Med Chem ; 268: 116204, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38364716

ABSTRACT

The involvement of CDC20 in promoting tumor growth in different types of human cancers and it disturbs the process of cell division and impedes tumor proliferation. In this work, a novel of Apcin derivatives targeting CDC20 were designed and synthesized to evaluate for their biological activities. The inhibitory effect on the proliferation of four human tumor cell lines (MCF-7, MDA-MB-231, MDA-MB-468 and A549) was observed. Among them, compound E1 exhibited the strongest inhibitory effect on the proliferation of MDA-MB-231 cells with an IC50 value of 1.43 µM, which was significantly superior to that of Apcin. Further biological studies demonstrated that compound E1 inhibited cancer cell migration and colony formation. Furthermore, compound E1 specifically targeted CDC20 and exhibited a higher binding affinity to CDC20 compared to that of Apcin, thereby inducing cell cycle arrest in the G2/M phase of cancer cells. Moreover, it has been observed that compound E1 induces autophagy in cancer cells. In 4T1 Xenograft Models compound E1 exhibited the potential antitumor activity without obvious toxicity. These findings suggest that E1 could be regarded as a CDC20 inhibitor deserved further investigation.


Subject(s)
Antineoplastic Agents , Diamines , Triple Negative Breast Neoplasms , Humans , Cell Proliferation , Triple Negative Breast Neoplasms/pathology , Apoptosis , Carbamates/pharmacology , Cell Line, Tumor , Cell Cycle Proteins , Antineoplastic Agents/chemistry , Drug Screening Assays, Antitumor , Cdc20 Proteins
2.
Clin Oral Implants Res ; 24(8): 853-61, 2013 Aug.
Article in English | MEDLINE | ID: mdl-22168601

ABSTRACT

OBJECTIVES: Evaluate hBMP-2 expression following gene delivery from plasmid multilayers formed on sandblasted titanium in vitro and bone formation around similarly prepared implant surfaces in vivo. MATERIALS AND METHODS: Multilayers of cationic lipid/rhBMP-2 plasmid DNA complex (LDc) and anionic hyaluronic acid (HA) was assembled on sandblasted-dual acid etched pure titanium disks or implant surfaces using layer-by-layer (LBL) assembly. Gene delivery and hBMP-2 expression in cells exposed to the LDc multilayers was measured in vitro. To determine the effect of BMP delivery from such multilyaers in vivo, roughened implants coated with BMP-2 LDc multilayers or uncoated control implants (n = 15 for both) were implanted in the femurs of NZW rabbits. After 2, 4, 8 weeks, femurs were retrieved and prepared for histomorphometric evaluation (n = 5 rabbits per time point). RESULTS: MC3T3-E1 cells cultured directly on the BMP-2 LDc coated titanium disks showed EGFP and hBMP-2 expression after 48 h in culture. Increased gene delivery occurred by increasing the number of assembly layers when cells were cultured for 48 h. Cells cultured on LDc coated surfaces had significantly higher cell viability than control cells cultured on uncoated porous titanium surfaces. Histologic observation of the implants showed that after 4 weeks healing, the bone to implant contact (BIC) on the LDc coated surface was much lower than that on the control surface, but didn't reach significant. In contrast, the percentage of bone within the implant's threads was significantly higher than the control group (P = 0.047). CONCLUSION: The BMP-2 gene coated sandblasted dual acid etched titanium implants slightly accelerated early bone formation around implants.


Subject(s)
Bone Morphogenetic Protein 2/pharmacology , Coated Materials, Biocompatible/pharmacology , Dental Implants , Dental Materials/chemistry , Femur/drug effects , Osteogenesis/drug effects , Titanium/chemistry , Transforming Growth Factor beta/pharmacology , 3T3 Cells , Acid Etching, Dental/methods , Animals , Bone Morphogenetic Protein 2/genetics , Cell Culture Techniques , Cell Survival/drug effects , Dental Etching/methods , Fluorescent Dyes , Green Fluorescent Proteins , Lipids , Liposomes , Mice , Osseointegration/drug effects , Osteoblasts/metabolism , Osteogenesis/physiology , Plasmids/genetics , Porosity , Rabbits , Recombinant Proteins/genetics , Recombinant Proteins/pharmacology , Surface Properties , Transfection/methods , Transforming Growth Factor beta/genetics
3.
Clin Oral Implants Res ; 24 Suppl A100: 34-41, 2013 Aug.
Article in English | MEDLINE | ID: mdl-22145854

ABSTRACT

OBJECTIVE: The objective of this study was to compare magnesium-substituted and pure hydroxyapatite coatings on the promotion of osteogenesis in vitro and on the osseointegration in vivo. METHODS: Electrochemically deposited pure hydroxyapatite (EDHA) or electrochemically deposited magnesium-substituted hydroxyapatite (EDMHA) coatings were formed on the surface of pure titanium disks or implants. MC3T3-E1 preosteoblasts were cultured in the EDHA and EDMHA coated disks, and cell growth, alkaline phosphatase (ALP) activity, and osteocalcin secretion were measured at various time points. For studies on osseointegration, 30 roughened implants coated either with EDHA or EDMHA (n = 15 for each coating) were implanted in the femurs of 15 NZW rabbits. After 2, 4, and 8 weeks, femurs were retrieved and prepared for histomorphometric evaluation (n = 5 for each coating at each time point). RESULTS: MC3T3-E1 cells cultured on EDMHA coated disks showed increased cell number, ALP, and osteocalcin secretion compared with the EDHA coated disks at all time points (P < 0.05 for all). Histologic observation of the coated implants showed woven bone in direct contact with both implant surfaces after 2 weeks and mature bone after 8 weeks. While there were no differences in the amount of bone between the threads at any time point, the percentage of implant in direct contact with bone (bone implant contact) was slightly higher along the EDMHA coated implants at 2 weeks (P = 0.086), although this difference was no longer seen at 4 and 8 weeks. CONCLUSION: Mg-substituted HA coated surfaces promote osteogenic differentiation of preosteoblasts in vitro and may improve implant osseointegration during the early stages of bone healing compared with pure EDHA coated surfaces.


Subject(s)
Coated Materials, Biocompatible/pharmacology , Dental Implants , Durapatite/pharmacology , Magnesium/chemistry , Magnesium/pharmacology , Osseointegration/drug effects , Osteogenesis/drug effects , Alkaline Phosphatase/metabolism , Animals , Dental Implantation, Endosseous , Electrochemistry , Femur/surgery , Implants, Experimental , Materials Testing , Microscopy, Electron, Scanning , Nanoparticles , Osteocalcin/metabolism , Rabbits , Surface Properties , Titanium/pharmacology
4.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 41(3): 239-44, 2012 May.
Article in Zh | MEDLINE | ID: mdl-22723157

ABSTRACT

OBJECTIVE: To construct a multiple-scale organized implant surface with super-hydrophilicity. METHODS: The SiC paper polished titanium disc was sandblasted and treated with HF/HNO3 and HCl/H2SO4, then acid-etched with H2SO4/H2O2. The physicochemical properties of the surfaces were characterized by scanning electron microscope, static state contact angle and X-ray diffraction. MC3T3-E1 cells were used to evaluate the effects of the surface on the cell adhesion, proliferation and differentiation. RESULTS: The acid-etching process with a mixture of H2SO4/H2O2 superimposed the nano-scale structure on the micro-scale texture. The multiple-scale implant surface promoted its hydrophilicity and was more favorable to the responses of osteoprogenitor cells, characterized by increased DNA content, enhanced ALP activity and promoted OC production. CONCLUSION: A multiple-scale implant surface with super-hydrophilicity has been constructed in this study, which facilitates cell proliferation and adhesion.


Subject(s)
Dental Etching , Dental Implants , Titanium/chemistry , 3T3 Cells , Animals , Cell Adhesion/drug effects , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Hydrophobic and Hydrophilic Interactions , Mice , Surface Properties , Titanium/pharmacology
5.
Int J Oral Maxillofac Implants ; 26(1): 115-22, 2011.
Article in English | MEDLINE | ID: mdl-21365046

ABSTRACT

PURPOSE: The aim of this study was to investigate the bone response to rough titanium implants treated with hydrofluoric acid/nitric acid (HF/HNO3) solution. MATERIALS AND METHODS: Implants were treated with HF/HNO3 solution (test implants) or without HF/HNO3 solution (control implants). Forty-five test and 45 control implants were inserted into both tibias of 15 rabbits. After 2, 4, and 8 weeks in situ, tibias were retrieved and prepared for removal torque testing and histomorphometric evaluation. The removed implants were prepared and observed with an electron microscope. RESULTS: Mechanical tests showed that mean removal torque values for the test implants were higher than those of the control implants after 8 weeks (33.1 Ncm versus 25.7 Ncm, P = .012). Histomorphometric analysis showed that the bone area in the threads of the cortical bone region was significantly higher for test implants (81.99% and 86.38%) than for control implants (75.33% and 81.62%) after 4 and 8 weeks of healing, respectively. The implant-bone contact rate in the cortical region was higher for test implants than for control implants after 8 weeks in situ (79.56% versus 68.45%, P = .003). CONCLUSIONS: The treatment with HF/HNO3 solution promotes bone formation and osseointegration after 4 and 8 weeks of bone healing in the rabbit tibia model.


Subject(s)
Acid Etching, Dental/methods , Dental Implants , Dental Materials/chemistry , Hydrofluoric Acid/chemistry , Nitric Acid/chemistry , Tibia/surgery , Titanium/chemistry , Animals , Carbon/analysis , Fluorides/analysis , Microscopy, Electron, Scanning , Osseointegration/physiology , Osteoblasts/pathology , Osteogenesis/physiology , Oxygen/analysis , Photoelectron Spectroscopy , Porosity , Rabbits , Stress, Mechanical , Surface Properties , Tibia/pathology , Time Factors , Titanium/analysis , Torque , Wound Healing/physiology , X-Ray Diffraction
6.
Int J Oral Maxillofac Implants ; 25(4): 669-80, 2010.
Article in English | MEDLINE | ID: mdl-20657861

ABSTRACT

PURPOSE: The purpose of this study was to investigate and compare bone formation on titanium implant surfaces coated with biomimetically deposited calcium phosphate (BDCaP) or electrochemically deposited hydroxyapatite (EDHA). MATERIALS AND METHODS: The implants were separated into three groups: a control group, a BDCaP group, and an EDHA group. Surface analysis was performed by field-emission scanning electron microscopy, x-ray diffractometry, and Fourier transform infrared spectroscopy. Implants were inserted in a randomized arrangement into rabbit tibiae. After 2, 4, and 8 weeks, the tibiae were retrieved and prepared for histomorphometric evaluation. RESULTS: Field-emission scanning electron microscopy showed that the BDCaP crystals were flakelike and the EDHA crystals were rodlike with a hexagonal cross section. X-ray diffractometric patterns and Fourier transform infrared spectroscopy spectra showed that the BDCaP coating consisted of HA and octacalcium phosphate, whereas the EDHA coating consisted of HA. Histologic observation showed that new bone on the EDHA-coated implant became mature after 4 weeks, while new bone on the control and BDCaP-coated implants was mature after 8 weeks. The EDHA implant showed significantly greater BIC and bone area compared to the control and BDCaP implants during 4 to 8 weeks. The BDCaP coating failed to show increased bone formation during the test period. CONCLUSION: The present EDHA coating has good bone formation properties, while the BDCaP coating has weaker bone formation properties.


Subject(s)
Biomimetic Materials/chemistry , Calcium Phosphates/chemistry , Coated Materials, Biocompatible/chemistry , Dental Implants , Dental Materials/chemistry , Durapatite/chemistry , Electroplating/methods , Osteogenesis/physiology , Titanium/chemistry , Acid Etching, Dental/methods , Animals , Dental Etching/methods , Dental Prosthesis Design , Microscopy, Electron, Scanning , Osseointegration/physiology , Rabbits , Random Allocation , Spectroscopy, Fourier Transform Infrared , Surface Properties , Tibia/pathology , Tibia/physiopathology , Tibia/surgery , Time Factors , X-Ray Diffraction
7.
J Oral Maxillofac Surg ; 68(5): 1131-9, 2010 May.
Article in English | MEDLINE | ID: mdl-20202734

ABSTRACT

PURPOSE: The purpose of this study was to investigate the effect of surface chemistry of a sandblasted and acid-etched implant (with and without titanium hydride [TiH(2)]) on cell attachment, proliferation, and differentiation of preosteoblasts (MC3T3-E1). MATERIALS AND METHODS: Sandblasted and dual acid-etched titanium discs comprised the test group, whereas sandblasted, acid-etched, and heat-treated discs comprised the control group. Both groups' discs were sent for surface characterization. MC3T3-E1 cells were cultured on these 2 groups' discs, and then cell attachment, cell proliferation, and cell differentiation were analyzed. RESULTS: Scanning electron microscope analysis showed that the titanium discs in the 2 groups shared the same surface topography; however, x-ray diffraction examination showed that the TiH(2) diffractions only appeared in the test group. Cell attachment and cell proliferation were much better in the test group than in the control group at all time points investigated (P < .05). The expressions of alkaline phosphatase and osteocalcin were significantly higher in the test group than in the control group for both protein and transcription level at every time point (P < .05 or P < .01). CONCLUSIONS: These results suggested that surface chemistry played a significant role in cell response to the sandblasted and acid-etched surface and the presence of TiH(2) might promote the attachment, proliferation, and differentiation of preosteoblasts.


Subject(s)
Dental Implants , Dental Materials/chemistry , Dental Prosthesis Design , Osteoblasts/physiology , Titanium/chemistry , 3T3 Cells , Acid Etching, Dental/methods , Alkaline Phosphatase/analysis , Animals , Biomarkers/analysis , Cell Adhesion/physiology , Cell Differentiation/physiology , Cell Proliferation , Dental Etching/methods , Hot Temperature , Hydrogen/chemistry , Materials Testing , Mice , Microscopy, Electron, Scanning , Osteocalcin/analysis , Osteogenesis/physiology , Reverse Transcriptase Polymerase Chain Reaction , Surface Properties , X-Ray Diffraction
8.
J Oral Maxillofac Surg ; 68(2): 420-7, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20116717

ABSTRACT

PURPOSE: The purpose of this study was to investigate the effects of biomimetically and electrochemically deposited hydroxyapatite on the fixation of an implant with bone tissue. MATERIALS AND METHODS: Implants were separated into 3 groups: roughened group, biomimetically deposited calcium-phosphorus (BDCaP) group, and electrochemically deposited hydroxyapatite (EDHA) group. We randomly inserted 90 implants into the femurs of 45 rabbits. After 2, 4, and 8 weeks, the femurs were retrieved and prepared for removal torque tests (RTQs) and field-emission scanning electron microscopy observation. RESULTS: During the test period, the EDHA group showed significantly greater RTQ values than did the roughened group and BDCaP group. The BDCaP group failed to increase the RTQ values compared with the roughened group. Field-emission scanning electron microscopy observation showed that the amount of attached bone tissue on the EDHA-coated implant surface was more than that on the roughened and BDCaP-coated implant surfaces during the test period. CONCLUSION: The electrochemical hydroxyapatite coating contributes to the fixation between bone and implant compared with the roughened surface, whereas the biomimetic calcium-phosphorus coating has little effect on the fixation.


Subject(s)
Biomimetic Materials , Coated Materials, Biocompatible , Dental Implants , Dental Prosthesis Design , Osseointegration , Animals , Calcium Phosphates , Device Removal , Durapatite , Electrochemical Techniques , Femur/surgery , Implants, Experimental , Materials Testing , Porosity , Rabbits , Surface Properties , Titanium
9.
Zhonghua Yi Xue Za Zhi ; 89(46): 3289-94, 2009 Dec 15.
Article in Zh | MEDLINE | ID: mdl-20193370

ABSTRACT

OBJECTIVE: To investigate the cross-talk between Notch1 and epidermal growth factor receptor (EGFR) signaling in regulating the cellular proliferation of human tongue squamous cell carcinoma (SCC). METHODS: Human tongue SCC cell line Tca8113 cells was transiently transfected with the vector encoding exogenous intracellular fragment of Notch1 and the vector encoding the specific short hairpin RNA (shRNA) targeting EGFR respectively and were treated by AG1478, an inhibitor of receptor tyrosine kinases, for elucidating the effects of constitutive activation, EGFR gene silencing and blocking EGFR signaling upon cellular proliferation and expression of Notch1 and EGFR. The mRNA and protein levels of Notch1 and EGFR were detected by reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot, respectively. The cellular proliferation was evaluated by methyl thiazolyl tetrazolium (MTT) assay. RESULTS: Constitutive activation of Notch1 resulted in inhibition of cellular proliferation, and up-regulation of Notch1 (1.102 +/- 0.135, 0.243 +/- 0.032, P < 0.05) but down-regulation of EGFR (0.083 +/- 0.009, 0.605 +/- 0.075, P < 0.05) at the the mRNA and protein levels. Silencing of EGFR gene resulted in inhibition of cell proliferation, and down-regulation of EGFR (0.148 +/- 0.019, 1.175 +/- 0.132, P < 0.05) but up-regulation of Notch1 (0.978 +/- 0.115, 0.083 +/- 0.009, P < 0.05) at the mRNA and protein levels. Blocking EGFR signaling had no significant effect upon EGFR expression (P > 0.05), but resulted in inhibition of cellular proliferation and up-regulation of Notch1 (P < 0.05) at the mRNA and protein levels. CONCLUSION: There might be a cross-talk of bi-directional control between Notch1 and EGFR signaling in regulating the cellular proliferation of human tongue SCC cells.


Subject(s)
Carcinoma, Squamous Cell/metabolism , ErbB Receptors/metabolism , Receptor, Notch1/metabolism , Signal Transduction , Tongue Neoplasms/metabolism , Carcinoma, Squamous Cell/pathology , Cell Line, Tumor , Cell Proliferation , Down-Regulation , Humans , Tongue Neoplasms/pathology , Up-Regulation
10.
Int J Oral Maxillofac Implants ; 23(6): 1020-8, 2008.
Article in English | MEDLINE | ID: mdl-19216270

ABSTRACT

PURPOSE: To investigate the effect of H2O/HCl heat treatment on peri-implant bone formation in vivo. MATERIALS AND METHODS: Twenty Ti-6Al-4V implants and 30 Ti-6Al-4V discs were used in this study. The implants and discs were separated into 2 groups: sandblasted and dual acid-etched group (control group) and sandblasted, dual acid-etched and H2O2/HCl heat-treated group (test group). Surface morphology, roughness, and crystal structure of the discs were analyzed by field-emission scanning electron microscopy, atomic force microscopy, and low angle X-ray diffractometry. The implants were inserted into the femurs of 10 adult white rabbits. Animals were injected with fluorescent bone labels at 1, 5, and 7 weeks following surgery to monitor progress of bone formation. Animals were euthanized 8 weeks postsurgery, and block biopsies were prepared for histologic and histometric analysis. RESULTS: Microscopic evaluation showed the surfaces were quite irregular for both techniques; however, the test surface demonstrated consistently smaller surface irregularities. The differences in Sa values were significant (P = .022). No significant differences were found in the maximum peak-to-valley ratio values (P = .258). X-ray diffractometry analysis showed that titanium dioxide was found on the test surface. New bone was formed on both implant surfaces. The bone-implant contact pattern appeared to produce a broad-based direct contact. Test implants demonstrated 7.13% more bone to implant contact (P = .003) and 15.42% more bone to implant contact for 3 consecutive threads (P = .001) than control implants. Test implants demonstrated 37.04% more bone area 500 microm outside of implant threads (P = .004) and 51.97% more bone area within 3 consecutive threads (P = .001) than control implants. No significant differences were found in bone area within all implant threads between the two groups (P = .069). CONCLUSION: This study demonstrated that implants heat-treated with H2O2/HCl solution enhanced peri-implant bone formation.


Subject(s)
Acid Etching, Dental/methods , Dental Alloys/chemistry , Dental Implants , Hydrochloric Acid/chemistry , Hydrogen Peroxide/chemistry , Osseointegration/physiology , Osteogenesis/physiology , Oxidants/chemistry , Titanium/chemistry , Alloys , Aluminum Oxide/chemistry , Animals , Biocompatible Materials/chemistry , Biopsy , Crystallography , Dental Etching/methods , Femur/pathology , Femur/surgery , Fluorescent Dyes , Hot Temperature , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Microscopy, Fluorescence , Rabbits , Surface Properties , X-Ray Diffraction
11.
Am J Orthod Dentofacial Orthop ; 132(3): 353-9, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17826604

ABSTRACT

INTRODUCTION: The purpose of this research was to study the potential anchorage of a newly designed bicortical microimplant for mesial movement of posterior teeth in the mandibles of beagle dogs. METHODS: Five adult male dogs with the third premolars in both arches extracted 1 week before the treatment were used in this study. Two bicortical microimplants were placed in the interradicular region at the center of resistance of the second premolar on each side of the mandible. One served as a loaded microimplant with 2 orthodontic nickel-titanium springs delivering 50 g of force between the bicortical microimplant and the fourth premolar. The contralateral bicortical microimplant without loading was the control. Implant-tooth measurements were made biweekly. At the end of tooth movement, the animals were killed, and the specimens with microimplants were embedded in methylmethacrylate and cut to 100 microm and ground to a thickness of 70 microm. Bone-to-implant contact was calculated. RESULTS: All bicortical microimplants remained stable. Obvious mesial movement of the fourth premolar was observed on the loaded side, but no movement was seen on the unloaded side. No evidence of infection was seen in the histologic examination of the bone interface, and no statistical difference in the bone-to-implant contact between sides was seen. CONCLUSIONS: A bicortical microimplant with 2 anchorage units can be used for bilateral orthodontic anchorage in protraction of the posterior teeth in the mandibles of beagle dogs.


Subject(s)
Orthodontic Anchorage Procedures/instrumentation , Tooth Movement Techniques/instrumentation , Analysis of Variance , Animals , Dental Implants , Dental Stress Analysis , Dogs , Male , Miniaturization , Orthodontic Appliance Design , Orthodontic Space Closure/instrumentation
13.
Arch Oral Biol ; 51(12): 1112-9, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16806049

ABSTRACT

Oral squamous cell carcinoma (OSCC) is the most common malignant tumour in the oral and maxillofacial region and has a poor prognosis. Cytokeratin 19 (CK19) is a component of cytoskeleton protein. Previous studies have reported abnormal expression of CK19 protein in OSCC tissue. This study is to investigate the quantitative level of CK19 gene transcript in OSCC tissue as well as its clinical significance. Thirty-one OSCC patients (26 males and 5 females) took part in the present study, aged 34-78 years (mean 58.2 years). The level of CK19 mRNA was detected using fluorescent quantitative real-time reverse transcriptase polymerase chain reaction (RT-PCR) in cancerous and paracancerous tissues. The relative quantification in cancerous tissue compared with paracancerous tissue was calculated using the 2(-DeltaDeltaCt) equation. The level of CK19 mRNA in cancerous tissue from OSCC patients was 2.21-fold higher than that in paracancerous tissue (P=0.020), and the amplicon was specific without genomic DNA contamination. The level of CK19 mRNA correlated significantly with the pathological differentiation grade of OSCC tissue (P=0.025), with poorer differentiation indicating a higher level of CK19 mRNA. These results suggest that fluorescent quantitative real-time RT-PCR is accurate and reliable for the detection of CK19 gene transcript levels in OSCC tissue. The level of CK19 mRNA was increased in OSCC tissue, and this was significantly correlated with the pathological differentiation grade.


Subject(s)
Carcinoma, Squamous Cell/chemistry , Keratin-19/genetics , Mouth Neoplasms/chemistry , RNA, Messenger/analysis , RNA, Neoplasm/analysis , Adult , Aged , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/mortality , Cell Differentiation/physiology , Female , Humans , Male , Middle Aged , Mouth Neoplasms/genetics , Mouth Neoplasms/mortality , Neoplasm Staging , Prognosis , Reverse Transcriptase Polymerase Chain Reaction/methods
14.
Int J Oral Maxillofac Implants ; 21(4): 629-34, 2006.
Article in English | MEDLINE | ID: mdl-16955616

ABSTRACT

PURPOSE: In recent years, microimplants have gained popularity in orthodontics. Microimplants are primarily placed in complex sites where critical anatomic structures, such as roots of teeth, may be damaged, so precise surgical planning is required prior to placement. The goal of this report was to introduce a newly developed technique for the placement of microimplants in interradicular areas and evaluate its accuracy. MATERIALS AND METHODS: The planned placement site is radiographed using a radiographic template and film holder fabricated by the investigators. The resultant radiograph is clipped and attached to the radiographic template to make a surgical template to guide the placement of the microimplant. Forty-one patients, 15 men and 26 women ranging in age from 21 to 29 years, were enrolled in this study. On 1 side of the arch, this novel technique was used for implant placement, and on the other side, an established method reported by Maino and associates (i.e., the control technique) was used. RESULTS: A total of 116 microimplants 2 mm wide and 9 mm long were placed interradicularly in 41 patients. Twelve of 58 microimplants were placed unsuccessfully in the control group, versus 2 of 58 in the test group. Statistical analysis showed that there was a significant difference between the 2 techniques in terms of success rate (P < .05). DISCUSSION: Presurgical diagnosis of bone quantity and transfer of the information to the surgical sites are vital in microimplant placement. Radiographic templates modified for surgical purposes have the advantage of transferring radiographic information directly to the surgical site. CONCLUSION: This study, although limited in some respects, demonstrated that microimplant placement can be improved using the newly developed technique described.


Subject(s)
Dental Implantation, Endosseous/methods , Dental Implants , Orthodontic Anchorage Procedures/methods , Orthodontics, Corrective/instrumentation , Radiography, Dental/instrumentation , Adult , Female , Humans , Male , Radiography, Dental/methods
15.
J Zhejiang Univ Sci B ; 7(8): 654-9, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16845720

ABSTRACT

BACKGROUND: Electrochemical therapy (ECT) has been used to treat unresectable hepatic tumor. In order to improve its efficacy, we combined ECT with hyperthermia induced by electrothermal needle (ETN) (ETECT). The aim of this study is to investigate the destructive effect of ETECT on normal rat liver. METHODS: Twenty rats were randomized into 4 treatment groups (n=5 in each group): control, ECT alone, hyperthermia alone and ETECT. Following the treatment, sections of the livers were histologically examined by light microscopy and the destructive volumes were measured with micrometer. RESULTS: We found that the destructive volumes in ETECT group were the largest (P<0.01). In ETECT group coagulative necrosis was found in both anode and cathode areas, around which transition zones existed. The transition zones can only be seen when coulomb was increased in ECT group. CONCLUSION: ETECT was demonstrated to enhance the destructive effect of ECT. This study provides theoretical and experimental basis for a new local ablative treatment for unresectable primary liver tumor.


Subject(s)
Electric Stimulation Therapy/methods , Hyperthermia, Induced/methods , Liver Neoplasms, Experimental/therapy , Animals , Electrochemistry , Female , Liver Neoplasms, Experimental/pathology , Rats , Rats, Sprague-Dawley
16.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 35(5): 479-84, 2006 09.
Article in Zh | MEDLINE | ID: mdl-17063538

ABSTRACT

OBJECTIVE: To observe regulation of nitric oxide on c-fos expression in osteoblastic cells in response to changes in wall-shear stress in vitro. METHODS: Isolated and purified osteoblastic cells from the calvaria of newborn SD rats were cultured and passaged. The third generation cells, pre-treated with 10% FBS DMEM, 0.3 mmol/L L-NMMA DMEM and 0.1 mmol/L SNP DMEM separately, were subjected to wall-shear stress of 1.2 Pa. Gene expression of the c-fos and NOS activity were studied before (0 min) and 10 min, 15 min, 30 min, 60 min after treated with wall-shear stress. RESULT: The expression of c-fos mRNA was increased transiently after application of 1.2 Pa wall-shear stress in osteoblastic cells and peaked at 15 min. The expression of c-fos mRNA was decreased after pre-application with L-NMMA and increased after use of SNP. CONCLUSION: Changes in the osteoblastic cells mechanical environment may cause a dramatic induction of NO and c-fos expression.


Subject(s)
Nitric Oxide/biosynthesis , Osteoblasts/metabolism , Proto-Oncogene Proteins c-fos/biosynthesis , Animals , Animals, Newborn , Biomechanical Phenomena , Cells, Cultured , Female , Male , Nitric Oxide/genetics , Nitric Oxide Synthase/metabolism , Osteoblasts/cytology , Proto-Oncogene Proteins c-fos/genetics , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Rats , Rats, Sprague-Dawley , Skull/cytology , Stress, Mechanical
17.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 35(5): 491-5, 2006 09.
Article in Zh | MEDLINE | ID: mdl-17063540

ABSTRACT

OBJECTIVE: To evaluate the potential anchorage of bicortical microimplant for tooth movement. METHODS: Five bicortical microimplants were inserted in the interradicular area of the second premolar (P2) in one side of the mandible (test side), 5 monocortical microimplant in the contralateral region (control side) in 5 beagle dogs. A total of 100 g force was generated between the implant and the fourth premolar (P4) in two sides. M1-P4, CA-IB and CA-M1 were measured biweekly. At the end of loading, specimens with P4 segments were cut and grounded to 70 microm to calculate the bone-to-implant contact (BIC). RESULT: All the bicortical microimplants remained stable during the treatment periods, while 1 monocortical microimplant was lost within 1 week. Mesial movement of P4 was ( 3.92+/-0.22) mm in the test side, (2.03+/-0.15) mm in the control side (P<0.05). Analysis showed no difference of the BIC between the bicortical microimplants and the monocortical microimplants. CONCLUSION: The bicortical microimplant may be used as orthodontic anchorage for mesial movement of posterior tooth.


Subject(s)
Dental Implantation, Endosseous/methods , Dental Implants , Orthodontic Anchorage Procedures/instrumentation , Tooth Movement Techniques/methods , Animals , Dogs , Male , Orthodontic Appliance Design , Orthodontic Appliances
18.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 35(1): 50-4, 2006 01.
Article in Zh | MEDLINE | ID: mdl-16470921

ABSTRACT

OBJECTIVE: To observe the apoptosis induced by exogenous NO in Tca8113 cells and to investigate the possible mechanism. METHODS: SNP as NO donor was used to treat the tongue squamous cell carcinoma Tca8113 cells. Cytotoxic and apoptotic effects of NO on Tca8113 cells were examined by using MTT assay, acridine orange (AO) staining, Wright-Giemsa staining, agarose gel electrophoresis and flow cytometry. Western blot was performed for investigating the apoptotic mechanism. RESULTS: NO had a remarkable proliferation inhibiting effect on Tca8113 cells. After being exposed to exogenous NO, Tca8113 cells showed series of apoptotic morphological changes such as cell shrinkage, nuclear condensation; and also showed DNA fragmentation, G2/M phase arrest as well as upregulation of the tumor suppressor P53 protein. CONCLUSION: Exogenous NO has a proliferation inhibition and apoptosis induction effect on Tca8113 cells in a concentration and time-dependent manner, P53 protein may be involved in the apoptosis induced by NO.


Subject(s)
Apoptosis/drug effects , Carcinoma, Squamous Cell/pathology , Nitric Oxide/pharmacology , Tongue Neoplasms/pathology , Tumor Suppressor Protein p53/biosynthesis , Antineoplastic Agents/pharmacology , Carcinoma, Squamous Cell/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Tongue Neoplasms/metabolism , Tumor Suppressor Protein p53/genetics
19.
Oral Oncol ; 41(8): 785-90, 2005 Sep.
Article in English | MEDLINE | ID: mdl-15979383

ABSTRACT

Nitric oxide has been reported to have cytotoxic effects in several tumor cells. The objective of this study was to investigate the effects of exogenous nitric oxide on apopotosis in oral squamous cell carcinoma cells and to reveal its possible mechanism. Tca8113 cells were cultured with various concentrations of nitric oxide that were released from sodium nitroprusside (SNP). Nitrite/nitrate levels in the culture supernatant were determined using a commercial available nitric oxide kit. Cellular proliferation was determined by MTT assay. Apoptosis was detected by flow cytometry. Expression of inducible nitric oxide synthase (iNOS) was determined by immunocytochemistry. p53 expression was assessed by Western blot. SNP can release nitric oxide into the culture medium in a dose-dependent manner. Nitric oxide remarkably inhibits proliferation in a dose and time-dependent manners and lead to apoptosis of the Tca8113 cell. The p53 expression was elevated accompanying by the increased apoptotic cells. No difference of iNOS was found whether or not the cells were treated with SNP. Exogenous nitric oxide had an inhibitory effect on Tca8113 cells proliferation in a dose and time-dependent manners and possibly via p53 dependent apoptosis pathway. Exogenous nitric oxide had no significant effect on cellular iNOS protein.


Subject(s)
Apoptosis , Carcinoma, Squamous Cell/pathology , Nitric Oxide/pharmacology , Tongue Neoplasms/pathology , Tumor Suppressor Protein p53/metabolism , Humans , Nitric Oxide Synthase Type II/metabolism , Tumor Cells, Cultured/drug effects
20.
Article in English | MEDLINE | ID: mdl-14970773

ABSTRACT

PURPOSE: To reconstruct immediately the maxilla with bone grafts after partial maxillary resection and solve complications of exposed bone grafts to the maxillary sinus leading to a high rate of bone infection and sequestration. STUDY DESIGN: Thirty-eight patients were treated by immediate reconstruction of the maxilla with bone grafts supported by pedicled buccal fat pad (BFP) graft. The facial contour, the bone healing of the bone grafts, and the function of the maxillary sinus were evaluated with the Waters radiograph and speech evaluation. RESULTS: The postoperative healing was satisfactory with normal mouth opening and symmetrical contour of the face. The function of the maxillary sinus was restored with satisfactory speech and symmetrical density on radiograph and the healing of the bone grafts was good without complications such as bone resorption and sequestration. CONCLUSIONS: Immediate reconstruction of the maxilla with bone grafts supported by pedicled BFP grafts can restore the facial contour and the function of the maxillary sinus for the patients with partial maxillary resection. It provides a good method to reconstruct the maxillary defects and function in the mouth.


Subject(s)
Adipose Tissue/transplantation , Bone Transplantation , Maxilla/surgery , Plastic Surgery Procedures , Surgical Flaps , Adolescent , Adult , Bone Density/physiology , Face/anatomy & histology , Female , Follow-Up Studies , Humans , Male , Maxillary Diseases/surgery , Maxillary Neoplasms/surgery , Maxillary Sinus/diagnostic imaging , Maxillary Sinus/surgery , Middle Aged , Radiography , Speech/physiology , Wound Healing/physiology
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