Experimental study of superparamagentic scaffolds used to repair rabbit mandibular defect / 医学研究生学报

Objective Sperparamagnetic material is widely used in tumor localization and treatment , but there are still few studies in bone tissue engineering .This study aims to investigate the osteogenic efficiency of superparamagnetic scaffolds poly lactic acid hydroxy acetic acid (PLGA)/iron-doped hydroxyapatite (Fe-HA) for repairing rabbit mandibular defects , as well as evaluating the biocompatibility of the material . Methods 36 New Zealand rabbits were randomly selected and randomly divided into 6 groups, control without and with static magnetic field ( SMF ) groups ( no material is implanted), PLGA scaffold without and with SMF groups (implanted PLGA), PLGA/Fe-HA scaffold without and with SMF groups ( im-planted PLGA/Fe-HA), each group has 6 rabbits.We created bilat-eral mandibular defect models , executed the rabbits at 4 weeks and 12 weeks post-surgery, marked the mandibular specimens which detected by general observation, Micro-CT and HE staining, and ana-lyzed the results of bone mineral density in defect area .The hematological detection , pathological examination of liver and kidney sam-ples were carried out at 12 weeks pot-surgery.. Results The PLGA/Fe-HA scaffold without and with SMF groups began to appear rough defect area edge , decreased defect diameter , new bone formation from 4 weeks; the defect area formed a smooth , continuous bone repair from 12 weeks.The PLGA scaffold without and with SMF groups appeared rough , irregular callus repair , visible boundary between defect edge and normal bone tissue .There are still have part of unrepaired bone defect in the center of defect area in the control without and with SMF groups.At 12 weeks , the bone mineral density of PLGA/Fe-HA scaffold with SMF group [(572.50±19.09) mgHA/cm3] , respectively, compared with the PLGA scaffold with SMF group [(467.00±6.24)mgHA/cm3], the control with SMF scaffold group [(480.00±2.08) mgHA/cm3], the PLGA/Fe-HA scaffold without SMF group [(461.00±19.79)mgHA/cm3], the PL-GA scaffold without SMF group [(446.00±11.31)mgHA/cm3] and the control without SMF group [(422.00±28.28) mgHA/cm3], all the differences were statistically significant ( P<0.05).The bone mineral density of PLGA/Fe-HA scaffold with SMF group at 4 weeks [(572.50±19.09)mgHA/cm3] was significantly higher than that at 12 weeks [(276.00±28.28)mgHA/cm3] (P<0.05), the differences between 4 weeks and 12 weeks in other groups were statistically significant (P<0.05). Conclusion The superparama-gentic PLGA/Fe-HA scaffolds can promote the repair of bone defect , optimize the osteogenic effect of the material with SMF .Also ,the scaffold showed a good biocompatibility .

Porphyromonas gingivalis infection enhanced the adhesion of monocytes to endothelial / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To observe if Porphyromonas gingivalis (Pg) infection could enhance the adhesion of human monocytic cell line (THP-1) to human umbilical vein endothelial cells (HUVEC).</p><p><b>METHODS</b>PgATCC33277 was cultured in anaerobic jar, and THP-1 was infected with various concentrations of PgATCC33277 at multiplicity of infection (MOI) of 1: 100 for 8 and 24 hours, respectively. After removal of the free Pg, THP-1 cells were cocultured with HUVEC for 1 hour to observe the adhesion of THP-1 to HUVEC.HUVEC with adhesive THP-1 cells were co-cultured for additional 23 hours. The medium and cells were separately collected. The expression of related chemotactic cytokine[monocyte chemotactic protein 1(MCP-1) and interleukin 8(IL-8)] and intercellular adhesion molecule-1(ICAM-1) were detected with enzyme-linked immunosorbent assay.</p><p><b>RESULTS</b>The adhesion of THP-1 to HUVEC was enhanced (13.8%-35.2%, P = 0.006) and the expression of ICAM-1 of HUVEC was increased from (132.5 ± 7.7) to (164.9 ± 9.1) ng/L (P = 0.005) after infection for 24 hours by Pg. Both of the secreted MCP-1 and IL-8 elevated after infection of Pg for 24 hours from (183.2 ± 3.1) to (221.0 ± 4.9) ng/L (P = 0.012) and from (587.2 ± 5.1) to (787.2 ± 10.3) ng/L (P = 0.002), respectively.</p><p><b>CONCLUSIONS</b>Pg could enhance the adhesion of monocytes to endothelial cells and stimulate the inflammation, suggesting that Pg infection may be one of the risk factors in promoting the development of atherosclerosis.</p>

Ephrin B2 is involved in Porphyromonas gingivalis infection-enhanced adhesion of THP-1 to human umbilical vein endothelial cells / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the mechanisms of Porphyromonas gingivalis (Pg) infection-mediated enhancement of adhesion between monocytes THP-1 and human umbilical vein endothelial cells (HUVEC) by detecting the effect of erythropoietin producing hepatomocellular receptor interacting protein B2 (Ephrin B2) and its receptors on the adhesion.</p><p><b>METHODS</b>PgATCC33277 was cultured in an anaerobic jar, and THP-1 cells were infected with various concentrations of Pg at multiplicity of infection (MOI) of 1:100 for 8 and 24 h, respectively. The expression of Ephrin B2 receptor of THP-1 cells was detected. After removal of the free Pg, THP-1 cells were cocultured with HUVEC (overexpress of EphrinB2 or not) for 24 h to detect the expression of Ephrin B2 of HUVEC cells after additional cultivation for 23 h.</p><p><b>RESULTS</b>The adhesion of THP-1 cells post infection by Pg to HUVEC was enhanced. The mRNA levels of Ephrin B2 receptors, including EphB3 (5.169±0.152, P = 0.005), EphB4 (11.040±1.195, P = 0.001), and EphA4 (4.976± 0.122, P = 0.001) expressed by THP-1, and Ephrin B2 (8.938±0.962, P = 0.008) expressed by HUVEC were significantly elevated 24 h post infection of Pg. Over expression of Ephrin B2 in HUVEC promoted the adhesion of THP-1 to HUVEC.</p><p><b>CONCLUSIONS</b>Ephrin B2 and its receptors are involved in Pg infection mediated enhancement of the adhesion of THP-1 to HUVEC cells, suggesting that Ephrin B2 participates in the development of atherosclerosis.</p>

The clinical effect of root amputation in the treatment of periodontal/alveolar abscess / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the clinical effect of root amputation in the treatment of periodontal/alveolar abscess teeth with one severe lesion root.</p><p><b>METHODS</b>30 periodontal/alveolar abscess teeth with one severe lesion root were chosen in the study. After root canal treatment, supragingival scaling, subgingival scaling and root planning, occlusal adjustment were done. Then the teeth were treated by root amputation. The clinical effect was evaluated 3 months, 6 months and 1 year after surgery.</p><p><b>RESULTS</b>One year after surgery, 27 of 30 teeth were successful, 1 mandibular molar occurred root fracture, 1 mandibular molar was removed because of tooth loosening secondary to periodontal damage. 1 patient lost.</p><p><b>CONCLUSION</b>Root amputation is an effective solution of periodontal/alveolar abscess.</p>

Morphometric and functional alterations of amygdale and hippocampus in patients with depression: a MRI study / 中华放射学杂志

Objective To explore the morphometric and functional alterations of amygdale and hippocampus in patients with depression by anatomical and functional MRI, and try to reveal the pattern and pathogenesis of the changes in depression. Methods Sixty patients (divided equally into mild, moderate and major groups according to patient′s scores of HAMD) and 20 healthy control groups were scanned using T1WI and fMRI. The outlines of hippocampus and amygdale were drawn manually by observer and the volumes were calculated and normalized subsequently. Functional MRI was processed using SPM5 and individual activation map was got subsequently. Dunnett-t test and Pearson correlation analysis were separately used to analyze the morphometric and functional changes and the correlations between cerebral changes and clinical severity. Results The hippocampal volumes of control groups were 2296±202 left for left side and 2283±199 for right side. The hippocampal volumes of depressive patients were smaller than those of control groups, especially for the major group (left 1978±176,Dunnett-t=-10.0,P0.05,right 2210±191,Dunnett-t=-1.6,P>0.05). The amygdale′s volumes of control groups was 1762±185,the right was 1749±182, while those in patient group reduced along with the patient′s condition, i.e., the mild groups (left 1992±200,Dunnett-t=4.8,P<0.01,right 1989±191, Dunnett-t=5.0,P<0.001), the moderate groups (left 1889±192, Dunnett-t=2.8,P<0.05,right 1896±195,Dunnett-t=2.8,P<0.05), and the major groups (left 1539±178,Dunnett-t=-6.8,P<0.01,right 1543±180,Dunnett-t=-7.0,P<0.01).For fMRI study, patient group demonstrated more activation of the amygdale and hippocampus under the stimulations of negative images than controls. Furthermore, the strengthens of activation decreased along with the patient′s condition, i.e., the major ones showed the weakest activation among the patients, though it was higher than that of control group. In patient group, both the volumes and activations of hippocampus and amygdale showed significant negative correlations with HAMD scores(r=-0.80--0.90,P＜0.05). Conclusion The hippocampal volumes of depressive patients reduced, which may be due to the change of the amygdale, and the amygdale′s volumes were changed along with the patient′s condition. There were more activation in the amygdale and hippocampus of depressive patients under the stimulations of negative images.

MRI enhancement scanning features and pathology of the orthotropic transplantation nude mouse model with human pancreatic cancer / 中华胰腺病杂志

Objective To investigate the MRI imaging features, and pathologic basis of the orthotropic transplantation nude mouse model with human pancreatic cancer. Methods Adopting Siemens Magnetom Trio Tim 3.0 Tesla superconductive MRI and breast coil was used to examine 30 orthotropic transplantation nude mouse models of the human pancreatic cancer, these mouse were sampled to acquire TSE-T1 -weighted and T2-weighted transverse axial images. Intraperitoneal injection of Gd DTP A was used to perform continuous dynamic enhancement scanning. Signal intensities of tumors were measured in plain scanning and each phase' s enhancement scanning images, respectively. Intensification rates of tumors were calculated. Pathologic examination of tumors was performed to be compared with the findings of MRI scanning. Results The successful rate of inoculation of 30 nude mice was 100%. The histological findings were comparable with poorly differentiated adenocarcinoma. Compared with signal of adjacent tissues, the MRI findings of the tumors were uniformly slightly hypointensity (90% , 27/30) , or unevenly (10% , 3/30) on TSE-T1WI; uniformly (20% , 6/30) or unevenly (80% , 24/30) hyperintensity with equal or more hyper signal spots on TSE-T2WI. Signal intensities on plain scanning was 228.35 ±11.71, and 1.5,3,6,9, 12 min after enhancement scanning, thesignal intensities were 258.20 ± 11.17, 301.75 ± 17.09, 358.65 ±25.13, 480.05 ± 19.01, 558.35 ± 40.49, which were significantly higher than those in plain scanning (P <0.01). The intensification rate of every phase was 0.13 ±0.04, 0.35 ±0.11, 0.56 ±0.10, 1.10 ±0.10, 1.45 ±0.18, and the difference among these phases was statistically significant (P <0.01). The significantly intensified area was the area where the tumor cells grew actively with rich capillaries; the central area without intensification was the area of necrotic tissue and/or densely packed tumor cells and few capillaries. Conclusions High resolution MRI imaging of implanted tumors can be obtained by intraperitoneal injection of contrast, and it is consistent with pathologic examinations.

Dynamic research about the change of the behavior and hippocampal volume of rat depressive model / 中华行为医学与脑科学杂志

Objective To explore the dynamic change and correlation of the behavior and hippocampal volumes by MRI of rat depressive model. Methods Based on the evaluation of ethology, thirty SD rats were randomly and equally divided into control group and model group which was exposed to chronic unpredictable mild stress for 8 weeks. The body weight, fluid consumption test and Morris water maze test were done at the beginning and per week while the bilateral hippocampal volumes of every rat were measured by high field MRI at the beginning and per two weeks. Results Based on the behavioral data,the rat depressive model was established successfully,and changed dynamically. On 4th week,the left hippocampal volumes of depressive rat were significantly reduced (model group(37.13 ±2.40)mm3 ,control group (39.05 ±2.05)mm3, t=2.36, P＜0.05) while the right ones did not. On 6th week, the right ones began to reduce significantly ( model group ( 37.85 ± 2.11 ) mm3, control group ( 39.44 ± 2.10 ) mm3, t = 2.07, P ＜ 0.05 ) while the left one still reduced, but the extent of the left's reduction was bigger than the right( left:15% ,right:8% ). And there was apparent correlation between the behavior and the reduction of hippocampal volumes. Conclusion The behavior and hippocampal volumes of rat depressive model changes dynamically,and there was a regularity of them.

Establishment and magnetic resonance imaging monitoring of the orthotopic transplantation nude mouse model with human pancreatic cancer cell line PANC1 / 中华胰腺病杂志

Objective To establish a stable orthotopic transplantation nude mouse model of the human pancreatic cancer and to explore the role of monitoring tumor growth with noninvesive MRI.Methods The tumors cells suspension made by the subcutaneous injection of human pancreatic cancer cell lines PANC1 were used as the source of tissue for orthotopic implantation of tissue.and transplanted into the pancreas of 20 BALB/C-nu nude mice.After implantation,the successful rate,tumor formation time,tumor growth speed,tumor shape and the change of signal of the tumor were monitored and recorded noninvasively by MRI.At the end of the 7th week,all the specimens were examined by pathological methods.Results Thirty-five percent (7/20)mice with implantation of primary human PANC1 adenocarcinoma cells were detected to have orthotopic implanted tumors by MRI after 15 days,and all the 20 nude mice developed pancreatic tumor within 27 days after operations,and the successful rate was 100%.Compared with adjacent normal tissue,the T1 WI imaging of 90%(18/20)of all the tumors showed uniformly hypo-intense signal,10%(2/20)showed iso-intense signal,the T2W 75%(15/20)showed uniformly hyper-intense signal.The tumor size 2,3,4,5,6,7 weeks after implantation was(912.6±2.4)mm3,(94.3±11.2)mm3,(175.9±82.5)mm3,(395.8±126.6)mm3,(1290.2±167.2)mm3,(1583.4±87.4)mm3,respectively.Pathologic examination confirmed poody differentiated pancreatic adenocatcinoma and it remained the primary tumor's biolosic features.Conclusions The orthotopic transplantation nude mouse model was in accordance with the feature of human pancreatic cancer and was easy for noninvasive monitoring,which provided an effective and stable in vivo experimental system.

The Dynamic CT Study of Peripheral Lung Cancer and Pulmonary Inflammatory Pseudotumor / 实用放射学杂志

Objective To investigate the dynamic CT features of peripheral lung cancer (PLC) and pulmonary inflammatory pseudotumor(IPT).Methods 23 patients with PLC and 6 patients with IPT were undergone plain and dynamic enhanced CT scans (beginning at 30 s after the onset of injection,serial scan were obtained at 30 s intervals within 180 s) before surgery or administration of antibiotic.Results The average CT values of plain CT,CT enhanced attenuation at 30 s and 90 s were significantly different between PLC and IPT.There were no significant decline following peak enhancement in IPT but PLC within 180 s.Conclusion The comprehensive analysis of plain CT value,enhanced CT value at 30 s,and the decreasing rate after 90 s of administration of contrast material may be useful in differential diagnosis between PLC and IPT.

The Relationship Between p16 Expression and Angiogenesis as well as Value of CT Enhancment in Peripheral Lung Cancer / 实用放射学杂志

Objective To study the relationship between expression of p16 and tumor angiogenesis as well as value of CT enhancement in peripheral lung cancer. Methods twenty-three patients with peripheral lung cancer were examed with dynamic CT scan before surgery.The MVD、protein expression of VEGF and p16 were measured immunohistochemically on speciments of resected tumors.Results There were negative correlation tendency between expressions of p16 and VEGF,but the difference were no significant.During the course of delaying 30 s from injecting contrast dose,the relating coefficient was the highest between enhanced CT value and MVD,P=0.9364.The mean value of MVD and CT enhancement in the course of delaying 30 s in p16 negative expression group were higher than that in the group of p16 positive expression with no significant.Conclusion p16 negative expression may improve angiogenesis in peripheral lung cancer.