RESUMEN
Objective:To investigate the effects of metformin on the expression of high mobility group box 1 (HMGB1) and receptor for advanced glycation end product(RAGE) around implants in type 2 diabetic rats and underlying mechanism on bone bonding. To investigate the effect of metformin on osseointegration in non-diabetic rats.Methods:Forty male SD rats aged 6 to 8 weeks were randomly divided into 4 groups by random number table with 10 rats each: normal group (T0 group), normal+ metformin group (T1 group), diabetic group (T2 group), and diabetic+ metformin group (T3 group). After type 2 diabetes model was established in T2 and T3 groups, pure titanium implants were implanted in bilateral tibial epiphyseal of all rats. On the same day, T1 and T3 groups were given 300 mg·kg -1·d -1 metformin, and other groups were gavaged with the same amount of normal saline. At the 4th and 8th week after surgery, 5 rats in each group were randomly sacrificed, and bone structure was examined using HE staining and micro-computed tomography (micro-CT). The expression of related factors was detected with immunohistochemistry and enzyme linked immunosorbent assay. Results:At the 4th and 8th week after surgery, the trabecular bone structure, new bone formation quality, and bone microparameters in T3 group were better than those in T2 group. Compared with T2 group, the expression of HMGB1 and RAGE was decreased, the content of osteocalcin was increased, and the expression of tumor necrosis factor-α was decreased (all P<0.01). 4 weeks after operation, bone volume/tissue volume and trabecular number in T1 group was higher than that in T0 group [(0.569±0.013)% vs (0.523±0.030)%, P=0.014; (1.695±0.059)/mm vs (1.569±0.050)/mm, P=0.007]. 8 weeks after operation, trabecular number in T1 group was higher than that in T0 group [(2.324±0.337)/mm vs (1.882±0.057)/mm, P=0.042]. Compared with T0 group, the content of RAGE in T1 group was significantly decreased [(35.49±2.77)ng/L vs (44.92±7.99)ng/L, P=0.005]. The osteocalcin content in T1 group was significantly higher than that in T0 group [(1.32±0.19)ng/L vs (0.89±0.26)ng/L, P=0.001]. Conclusions:Metformin can reduce the expression of HMGB1 and RAGE in type 2 diabetic rats, which may be one of the mechanisms promoting implant bone binding. Metformin has bone protective effect on non-diabetic rats.
RESUMEN
Objective:To investigate the CT characteristics of bronchiolar adenoma (BA) in order to improve the understanding of the disease and to increase the accuracy of preoperative diagnosis.Methods:The clinical, imaging and pathological data of 69 patients with BA confirmed by surgical resection and pathology at Cancer Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences from December 2018 to November 2020 were retrospectively reviewed. The type, the location and the size of the lesions, the distance from the lesion to the adjacent pleura, as well as the morphological characteristics including lobulation, spiculation, bubble lucency and pleural indentation were analyzed and recorded. The follow-up CT data were also reviewed.Results:Among 69 BAs, pre-operation chest CT displayed visible lesion in 25 cases, and showed negative in 44 cases. According to the lesion density, the 25 BAs on CT images were classified into solid type ( n=8), ground-glass type ( n=8), cystic type ( n=6) and cyst type ( n=3). There were 15 lesions in the right lung (1 in the upper, 2 in the middle and 12 in the lower lobe) and 10 lesions in the left lung (5 in the upper and 5 in the lower lobe). Ten lesions were found adjacent to the pleura. As for the other 15 cases, the distance between the lesion and the adjacent pleura was (10±7) mm. Calcification was displayed in one cystic type BA case. The maximum diameter of 25 BAs were 4.4-30.3 mm, with the median value of 9.6 mm. The lobulation, spiculation, bubble lucency, and pleural indentation of lesions were detected in 20, 11, 12, and 6 cases. In total there were 11 patients received the preoperative follow-up CT, and 4 cases showed enlargement in diameter (including 2 cases of solid type, 1 of ground-glass type and 1 of cystic type). The growth rate was 0.43-2.14 mm/year, with the median value of 1.67 mm/year. Imaging signs including spiculation ( n=1), bubble lucency ( n=1) and lobulation ( n=1) were newly discovered on the preoperative follow-up CT. Postoperative follow-up CT was performed in 13 cases, without any recurrence or metastasis found. Conclusions:CT imaging features of BA usually display as a single pulmonary solid or ground-glass nodule, and also can be presented as cystic or cyst type in several cases. Lesions can appear the lobulation, spiculation and bubble lucency, with calcification rarely found. A few of BA cases can enlarge during follow-up.
RESUMEN
Objective@#To evaluate the effect of semaphorin 3A (Sema3A) pre-treated bone marrow mesenchymal stem cells (BMSC) sheets on new bone formation in type 2 diabetes mellitus rats.@*Methods@#Type 2 diabetes mellitus (T2DM) were induced by injection of streptozotocin, and the BMSC were isolated, controlled, identified and induced into cell sheets. Fifteen T2DM rats were randomly divided into control, sheets and Sema3A-sheets group and the calvarial critical size defect (CSD) model of rats were established. The defect zone of rats from control group were implanted with bone powder. The defect zone of rats from sheets group were implanted with bone powder and BMSC sheets. The defect zone of rats from Sema3A-sheets group were implanted with bone powder and BMSC sheets pretreated with 1.0 mg/L Sema3A. After 8 weeks, the bone samples were harvested and analyzed by micro-CT scanning, HE staining for the evaluation of new bone formation, and the immunohistochemical analysis for the expression of osteogenesis-related proteins including type Ⅰ collagen (COL- Ⅰ ), bone morphogenetic protein-2 (BMP-2), and osteocalcin (OCN).@*Results@#The BMSC were isolated and cultured, and oil red O and Alizarin red S staining proved the multi-potential differentiation. Eight weeks after the establishment of calvarial CSD model, Sema3A-sheet group showed the most abundant new bone formation (0.516±0.070), with increased bone volume fraction, namely bone volume/tissue volume (BV/TV) compared with sheets group (0.319±0.050) and control group (0.224±0.037) (P<0.05), and the sheets group showed increased BV/TV compared with control group (P<0.05). While trabecular thickness (Tb.Th) control group showed no difference in three groups (P>0.05). HE staining also confirmed that Sema3A-sheets group showed the most new bone formation. Sheet group (0.174±0.051) compared showed difference with control group (0.099±0.033) (P< 0.05), and Sema3A-sheet group (0.421±0.069) showed increased bone formation compared with sheet group and control group (P<0.05). Immunohistochemistry showed that BMSC sheet increased the expression of osteogenesis-related proteins including COL-Ⅰ, BMP-2 and OCN, while Sema3A pretreatment showed more obvious increase of the expression of COL-Ⅰ and OCN.@*Conclusions@#The combined implantation of bone powder and Sema3A stimulated BMSC sheets significantly increased bone regeneration in vivo. Therefore, Sema3A pre-treated BMSC sheets transplantation provides a new strategy for restoring bone defect in T2DM.
RESUMEN
Objective@#To investigate the effect of aspirin on osseointegration around titanium implants in ostoeporotic rats and to provide evidence for future researches and clinical application.@*Methods@#A total of 60 female SD rats, aged 3-4 months, were divided into ovariectomy group (Ovx group, n=48) and sham-ovariectomy group (Sham group, n=12). The rats in Ovx group received ovariectomy and those in Sham group underwent sham-ovariectomy. Twelve weeks later, six rats in each group were randomly selected to confirm the osteoporosis models. The Ovx group was divided into 4 subgroups with 12 rats in each group, namely the osteoporosis group (OP group), and Aspirin groups (A1, A2, A3 group). Pure screw titanium implants were placed in the right tibia near metaphysis of all rats. Three days after implant surgery, aspirin groups were intragastrically administered aspirin at a dose of 2.06, 4.11, 8.21 mg·kg-1·d-1 (A1, A2, A3), and OP group and Sham group were fed the same amount of normal saline. Four and 12 weeks following implantations surgery, half of the rats in each group were randomly chosen and sacrificed. Implant bone contact rate (IBCR), combined bone lamella width (CBLW) and trabercular width (TW) were observed and calculated using histomorphometric measurement.@*Results@#Four weeks after implantations surgery, the TW and CBLW of rats in A1 group [(39.60±2.77) and (27.56±4.14) μm] and the IBCR, TW and CBLW of rats in A2 group and A3 group [A2: (47.21±4.19)%, (48.74±3.20) and (35.91±3.79) μm; A3: (47.35±6.07)%, (50.27±5.25) and (40.66±2.11) μm] were much higher than those in OP group [(33.89±7.17)%, (32.20±6.10) and (19.77±6.80) μm](P<0.05). In term of CBLW, there were no difference between A3 group and Sham group [(46.11±5.87) μm](P>0.05). Twelve weeks after implantations surgery, the IBCR and CBLW of rats in A1 group [ (85.86±3.64) %, (53.12±8.68) μm], and the IBCR, TW and CBLW of rats in A2 group and A3 group [A2: (85.64±3.97)%, (69.42±6.78) and (54.19±3.12) μm; A3: (86.22±3.48)%, (75.43±3.50) and (55.79±5.60) μm] were much higher than those in OP group [(77.20±7.14)%, (55.10±2.26) and (41.77±3.13) μm](P<0.05). In term of IBCR, there were no difference among A1 group, A2 group, A3 group and Sham group [(90.09±2.21)%](P>0.05).@*Conclusions@#The low dose aspirin could promote IBCR, CBLW and TW of osteoporotic rats implants.
RESUMEN
Objective@#To evaluate the adhesion, proliferation, alkaline phosphatase (ALP) activity and the expression of osteogenesis-related genes and osteoprotegerin (OPG)/receptor activator of NF-κB ligand (RANKL) of osteoblast-like cells on a type of near β-type titanium alloys (Ti-5Zr-3Sn-5Mo-15Nb, TLM) surfaces modified by the double glow plasma nitriding technology, and to investigate the effect of the modified surfaces on the initial functions of osteoblast-like cells. @*Methods@#The surfaces of TLM were modified by the double glow plasma nitriding technology. TLM surfaces without modification were used as control. Cell morphology was observed with scanning electron microscopy (SEM). Methyl thiazolyl tetrazolium (MTT) method was used to measure cell proliferation. Cell ALP activity was evaluated by using reagent kits. The mRNA expression of Runt-related transcription factor-2 (RUNX2), typeⅠcollagen alpha 1 chain (COLⅠ α1) and OPG/RANKL were examined by quantitative real-time PCR(qRT-PCR). @*Results@#Four hour following cell alture, cells on modified surfaces extend filopodia and intercellular junction was tight. Three days later, cell proliferation (0.277±0.007) was significantly higher than that in control group (0.249±0.004) (P<0.01). After two weeks, ALP activity on TLM modified layer (173.6±1.89) was significantly higher than that on unmodified TLM (162.6±2.4) (P<0.01). The mRNA expression of osteoblast marker RUNX2, COLⅠα1 were stronger than that in control group (P<0.05). The expression of OPG mRNA was higher than that in control group (P<0.01), and RANKL mRNA expression was significantly lower than that in control group (P<0.05). @*Conclusions@#The TLM surface modified by the double glow plasma nitriding technology has a positive effect on osteoblasts initial adhesion, proliferation and differentiation, and it can also improve expression of OPG mRNA and has an inhibitory effect on RANKL mRNA expression of osteoblasts.
RESUMEN
<p><b>OBJECTIVE</b>To study the electrochemical corrosion performance of a type of biomedical materials near beta titanium alloy(Ti-3Zr-2Sn-3Mo-25Nb, TLM) in artificial saliva before and after nitride changing, and to provide clinical basis for clinical application of titanium alloy TLM.</p><p><b>METHODS</b>The double glow plasma alloying technology was used to nitride the surface of titanium alloy TLM. The surface properties of the modified layer were observed and tested by optical microscope, scanning electron microscope, glow discharge spectrum analyzer, X-ray diffraction and micro hardness tester. Then, electrochemical measurement system was used to test and compare titanium alloy TLM's electrochemical corrosion in artificial saliva before and after its surface change. Finally, the surface morphology of the original titanium alloy and the modified layer was compared by scanning electron microscope.</p><p><b>RESULTS</b>By the technology of double glow plasma nitriding, the surface of the titanium alloy TLM had been successfully nitrided with a modified layer of 4-5 µm in thickness, uniform and compact. Its main compositions were Ti and Ti(2)N. The Microhardness of modified layer also had been improved from (236.8 ± 5.4) to (871.8 ± 5.2) HV. The self-corrosion potential in electrochemical corrosion tests had been increased from -0.559 V to -0.540 V, while the self- corrosion current density had been reduced from 2.091 × 10(-7) A/cm(2) to 7.188 × 10(-8) A/cm(2). Besides, alternating-current impedance(AC Impedance) had also been increased. With the scanning electron microscope, it's obvious that the diameter of corrosion holes on modified layer were approximately 10 µm. As to the diameter and number of corrosion holes on modified layer, they had been decreased comparing with the original titanium alloy.</p><p><b>CONCLUSIONS</b>The type of near beta titanium alloy TLM can construct a nitriding modified layer on its surface. Meanwhile, the performance of its anti- corrosion in artificial saliva has been improved, comparing to the original titanium alloy TLM.</p>
Asunto(s)
Materiales Biocompatibles , Química , Corrosión , Aleaciones Dentales , Química , Impedancia Eléctrica , Pruebas de Dureza , Métodos , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Saliva Artificial , Química , Propiedades de Superficie , Titanio , Química , Difracción de Rayos XRESUMEN
Objective To examine the expression of potassium channel mRNA in myocardial tissue of mice with low selenium.Methods Forty C57BL/6 mice were randomly divided into four groups according to body weight(18-22 g),10 mice in each group,half male and half female.The low-selenium treatment groups were fed with low-selenium diet(selenium content was 0.004 mg/kg) for 4,12 and 24 weeks,respectively,and the control group was fed with normal diet(selenium content was 0.256 mg/kg).The mice were killed by cutting neck method,hearts were taken out and RNA was extracted by Trizol method.The expressions of potassium ion channel genes (KCNA4,KCND2,KCND3,KCNE1,KCNE2,KCNJ2,KCNJ12 and KCNQ1) at the mRNA level in heart were determined using real-time polymerase chain reaction.Results In low-selenium 4 weeks group,the mRNA expressions of KCNA4 gene(25.3 ± 0.09) and KCND2 gene(4.85 ± 0.05) were higher than that of the control group (1.00 ± 0.00,1.00 ± 0.00,all P ＜ 0.05); in low-selenium 24 weeks group,the mRNA expression of KCNJ12 gene (22.7 ± 0.10) was higher than that of the control group(1.00 ± 0.00,P ＜ 0.05); the mRNA expressions of KCND3,KCNE1,KCNE2,KCNJ2,KCNQ1 genes were compared with the corresponding control groups,the differences were not statistically significant(all P ＞ 0.05).Conclusions Low selenium can affect the mRNA expression of mouse cardiac potassium ion channel genes.
RESUMEN
Objective To observe the influence of selenocysteine synthase(SEPSECS) on injury of human umbilical vein endothelial cell line EVC-304 induced by hydrogen peroxide (H2O2). Methods Transfection was conducted to transfect EVC-304 which was maintained in vitro. The cells were divided into four groups: control group, SEPSECS over-expression group, empty vector group and SEPSECS silenced expression group, then Real-time PCR and Western blotting were performed to detected SEPSECS mRNA and protein expression , respectively. Flow cytometry(FCM) was performed to detect cell cycle. Different concentrations of H2O2, which including 0, 200, 400, 600, 800, 1 000 μmol/L, were used to treat EVC-304 . Then malonaldehyde (MDA), superoxide dismutase(SOD) secreted by the cells which were treated with H2O2 for 6 h, were checked by MDA or SOD kit. Results The SEPSECS mRNA expressions of control, SEPSECS silenced expression, empty vector and SEPSECS over-expression groups were 1.03 ± 0.24, 0.43 ± 0.11, 0.98 ± 0.27 and 1.61 ± 0.13, respectively. The protein expressions of control, SEPSECS silenced expression, empty vector and SEPSECS over-expression groups were 1.00 ± 0.26, 0.51 ± 0.10, 1.12 ± 0.38 and 1.51 ± 0.20, respectively. There was a significant difference between control and SEPSECS silenced expression groups (all P 0.05). Meanwhile, MDA of SEPSECS silenced expression groups[(15.8 ± 0.5),(19.6 ± 1.5)μmol/L] were significantly higher than control groups[(12.4 ± 0.1),(17.1 ± 0.5)μmol/L, all P < 0.05], on the other hand, MDA of SEPSECS over-expression groups[(10.8 ± 0.4),(14.2 ± 1.1)μmol/L] were lower than empty vector groups [(12.7 ± 0.7),(16.2 ± 1.1)μmol/L, all P < 0.05], when the H2O2 concentration was 800 or 1 000μmol/L. The level of SOD was decreased along with the H2O2 concentration. SOD of SEPSECS silenced expression groups[(7.7 ± 0.4),(2.4 ± 0.3)μmol/L] were lower than control groups[(10.0 ± 1.0),(6.0 ± 0.6)μmol/L, all P < 0.05], on the contrary, SOD of SEPSECS over-expression groups[(11.3 ± 0.6),(12.7 ± 1.6)μmol/L] were higher than empty vector groups[(9.2 ± 0.6),(6.7 ± 0.2)μmol/L, all P < 0.05], when the H2O2 concentration was 800 or 1 000μmol/L. Conclusion Expression of SEPSECS has a significant protective role on damaged EVC-304 which was induced by H2O2.
RESUMEN
<p><b>OBJECTIVE</b>To analyze the effect on pronunciation and comfort level when 4 different major connectors (type 1: Palatal plate; type 2: Single palatal strap; type 3: Anterior-posterior joint palatal strap; type 4: Anterior-posterior joint palatal bar) were used in patients with Kennedy I deletion.</p><p><b>METHODS</b>Tirty young volunteers were chosen to wear 4 different major connectors. The pronunciation of consonants /s/, /t/, /j/, /sh/ were detected and the different formant parameters(F1 and F2) were analyzed by the computer speech analytical system. The comfort levels of 4 major connectors were compared by questionnaire survey.</p><p><b>RESULTS</b>1)There was no significant difference(P5).05) in pronunciation of consonants /s/, /sh/, /t/(F1 and F2) among the 4 types of connectors whatever wearing or not, but there was significant difference (P < 0.05) in pronunciation of consonant /j/ among wearing type 3, type 4 and no wearing. 2)There was no significant difference in comfort level (P > 0.05) among the four connectors.</p><p><b>CONCLUSION</b>The effect on pronunciation of patients with Kennedy I deletion was less when wearing the first and the second types of connectors than that of wearing the third and the fourth types of connectors. There was no significant difference in comfort level among the four connectors.</p>
Asunto(s)
Anciano , Humanos , Dentición , Diseño de Dentadura , Dentadura Parcial Removible , Diente Molar , Diente PrimarioRESUMEN
Mesenchymal stem cells (MSCs) not only exhibit a marked tropism for tumors,but also exert antitumorigenic activity or as an emerging vectors to express foreign genes continuously and efficiently within the tumor microenvironment,suppress tumor's growth and metastasis.Conversely,MSCs can accelerate tumor development through promoting tumor stroma remodeling and tumor vascular formation,inhibiting tumor local immune and changing tumor phenotype.The reason for this discrepancy may be attributable to different sources of MSCs,the heterogeneity of MSCs,differences in tumor microenviroment,or another factor that is not yet appreciated.
RESUMEN
Objective To explore the clinical application of reconstructing silicone elastomer nose prosthesis by means of selected laser sintering and wax powder PCPI. Methods Laser scanning was used to get the 3-D data of a nose model. Surfacere 10.0 etc softwares was used to reconstruct the nose by mirroring the digitalized model of absent nose. Selective laser sintering and wax powder was chosen to fabricate a wax nose model and the nose prosthesis made by silicone clastomer. Results Perfect silicone clastomer nose prosthesis was made for 2 patients. Conclusion This study suggests that the wax nose model and the new wax powder can meet the requirement of clinical expectation for maxillofacial prosthesis.
RESUMEN
Objective:To reconstruct a 3-D wax nose model and make a s ilicone elastomer nose prosthesis. Methods:Laser scanning was us ed to get the data of a nose model, selective laser sintering and wax powder wer e used to fabricate a wax nose model,the nose prosthesis was made by silicone el astomer. The differences in length(L),width(W),deepth(D),height(H) and tip-angl e(TA) among the nose models made with plaster, wax powder and silicone elastomer were compared. Results:L(mm) in plaster, wax and silicon e models was 36.61,36.60 and 36.60 respectively.W(mm),D(mm),H(mm) and TA(?) in the three kinds of models were the same:36.23,18.45,43.14 and 74.57 respectively .Conclusion:Nose model made of the wax powder is precise and can meet the requirements for maxillofacial prosthesis.