BJECTIVE: To explore the effect of different convergent conditions on accuracy of simulation results from a three dimensional finite element model of the pelvic ring.METHODS: A first-order linear load of 600 was applied on the S_1 vertebral endplate in an established three-dimensional finite element model. The step length was set to 0.1 s. The boundary condition was set as constraint of 6 degrees of freedom in the proximal femur. Static and dynamic explicit convergences with 6 different weight scale factors were calculated retrospectively,and all the simulated results were compared with the experimental results in order to verify the accuracy. RESULTS: The static convergence predicted most accurate with the linear regression coefficient 0.88. With the increase of weight scale factor, the time cost decreased. However, the accuracy of the predicted results decreased. There was statistically difference between the simulation results and experimental results when the weight scale factor achieved 3 000 (P<0.05) and the coefficient of linear regression was lower than 0.8.CONCLUSION: It suggested that as for the complex finite element model, especially when the model contains complex contact conditions, dynamic explicit convergence can be an alternative solution to static convergence if the latter failed. Also proper weight scale factor should be used to decrease the time cost under the condition that the error was in the limited.

BACKGROUND:Studies addressing coronary heart disease are largely dependent on the establishment of myocardial infarction animal models. It is very important that exploring a safe method with easy operation, less damage, long time survival and high survival rate for myocardial infarction animal model OBJECTIVE:To compare the pros and cons of two kinds of thoracotomy anterior descending coronary artery ligation to do myocardial infarction animal model. METHODS: Thirty healthy male New Zealand white rabbits were randomly divided into three groups: control, median sternotomy incision, and left sternal incision. The anterior descending coronary artery was ligated after thoracotomy. The operation time, amount of intraoperative bleeding, postoperative food intake, and recovery time of eating were monitored during the surgery and within 24 hours after the surgery. And myocardial enzyme indexes were also monitored within 24 hours after the surgery. Rabbits were detected with ultrasonic echocardiogram at 4 weeks. RESULTS AND CONCLUSION:Different levels of ST segment elevation appeared in median sternotomy and left sternal incision groups by echocardiogram. The success rate of modeling was 70% in median sternotomy incision group, and 80% in left sternal incision group. Within 24 hours post-surgery, the myocardial enzyme indexes in the two groups were significantly increased compared with before surgery (P < 0.05). At 4 weeks, the left ventricular ejection fraction and the left ventricular shortening fraction were significantly decreased when compared to before surgery (P< 0.05). The operation time was shorter, the amount of bleeding was less, the time of eating recovery was less and the amount of eating was much in median sternotomy group than in left sternal incision, with significant differences between he two groups (P < 0.05). The median sternotomy incision for the ligation of anterior descending coronary artery is better than the left sternal incision to establish myocardial infarction models.

Objective To review the long-term oncologic and functional outcomes of surgical treatment for pelvic chondrosarcoma at a single institution to further delineate surgical strategy of resection and function reconstruction.Methods All of 165 patients with pelvic chondrosarcoma that had been surgically treated between July 2000 and Dec 2013 were reviewed retrospectively.There were 102 male and 63 female patients who had a mean age of 43.5 (range,13 to 75) years.The resection type included Type T 16,type Ⅱ 18,type Ⅲ 11,type Ⅰ+Ⅱ 19,type Ⅱ+Ⅲ 63,type Ⅰ+Ⅳ 15,type Ⅰ+Ⅱ+Ⅲ 10 and type Ⅰ+Ⅱ+Ⅳ 13 cases.The pathology diagnosis was grade Ⅰ in 15,grade Ⅱ in 88,grade Ⅲ in 20,dedifferentiated in 28,mesenchymal in 12 and clear cell chondrosarcoma in 2 patients.Nine cases were secondary lesion following multiple exostoses.114 patients received no previous treatment while others were referred due to recurrent tumor.En bloc resection was achieved in 142 patients and intralesional resection in 23 cases.Twelve patients had a hemipelvectomy to achieve local tumor control,whereas 153 patients underwent a limb-salvage procedure.Spinal screw-rod system was used to reconstruct anterior pelvic ring after ilium resection.Modular hemipelvic endoprosthesis was utilized to reconstruct periacetabular defect after tumor resection while no reconstruction was performed after ischium and pubis resection.Results The median duration of follow-up was 54.1 (range,l0 to 159) months.147 (89.1％) patients were alive at the final follow-up,seven of which were alive with tumor.The estimated 5-year survival was 81.5％.Thirty-three patients (20％) had local recurrence,and twenty (12.1％) had lung metastasis.Recurrent case,sacroiliac joint involvement and intralesional resction were three risk factors for postoperative recurrence.Patients who received type Ⅱ+Ⅲ resection and reconstruction had a mean functional score of 23 according to MSTS 93.The mean MSTS 93 for patients with type Ⅰ+Ⅱ and type Ⅰ+Ⅱ+Ⅳ resection and reconstruction was 18.The wound complication rate was 15.8％.Two aseptic loosening and 2 pubic connection plate breakage were observed in hemipelvic endoprosthesis reconstruction.Conclusion Tumor grade correlates with overall or disease-free survival.For low-grade chondrosarcoma,adequate surgical margin can provide long-term local control while for high-grade cases,distant metastasis is the main case of treatment failure.Adequate surgical margin can be achieved in cases with acetabulum involved.However,aggressive surgical resection of pelvic chondrosarcoma still remains as a challenge for orthopaedic oncologists when the tumor invades the iliosacral joint,which necessitates careful preoperative plan and skilled surgical techniques.

Through the analysis of current situation of the setup of local professional institutions,the principles and characteristics,the author put forward countermeasures and suggestions to optimize the local medical professional institutions’ setup,to help local medical institutions’development and improve the quality of medicinal higher education.

As a novel targeting drug delivery system, acid-sensitive micelles have many advantages, such as increasing solubility of lipophilic drugs, acid-sensitive release, high drug loading, etc. They can load drugs though non-covalent encapsulation and covalent conjugation methods. In tumor tissues, drugs are released quickly from the depolymerized micelles with lipophilic copolymer protonation or lypohydrophilic copolymer hydrolysis and covalent conjugated drugs are released when the acid-sensitive covalent linkage breaks. This review mainly advances acid-sensitive micelles for the tumor targeting drug delivery systems from drug-loaded methods and release mechanisms.
Animals ; Antibiotics, Antineoplastic ; administration & dosage ; pharmacology ; Antineoplastic Agents, Phytogenic ; administration & dosage ; pharmacology ; Cell Line, Tumor ; Doxorubicin ; administration & dosage ; pharmacology ; Drug Carriers ; chemistry ; Drug Delivery Systems ; Humans ; Hydrogen-Ion Concentration ; Lactates ; chemistry ; Micelles ; Paclitaxel ; administration & dosage ; pharmacology ; Polyethylene Glycols ; chemistry ; Polymers

In recent years (2007 to 2011),although the overall number of rabies cases in China has decreased,there is evidence of emerging or re-emerging cases in regions without previous rabies cases or with low incidence of rabies.To investigate the origin and the factors affecting the spread of rabies in China,specimens were collected from 2007 to 2011 from provinces with emerging and re-emerging cases and tested for the presence of the rabies virus.Positive specimens were combined with sequences from GenBank to perform comparisons of homology and functional sites,and to carry out phylogenetic analyses.Out of these regions,five provinces had 9positive specimens from canine and cattle,and 34 canine or human specimens were obtained from previously high-incidence provinces.Complete sequences of G gene were obtained for these samples.Homology of the sequences of these 43 specimens was 87％-100％ at the nucleotide level and 93.7％ -100％ at the amino acid level.These G gene sequences were combined with reference sequence from GenBank and used to construct a phylogenetic tree.The results showed that 43 specimens were all assigned to China clade I and clade Ⅱ,with all specimens from emerging and re-emerging areas placed within clade I.Specimens isolated from Shanxi and Inner Mongolia in 2011 were distinct from previously-isolated local strains and had closer homology to strains from Hebei,Beijing and Tianjin whereas new isolates from Shanghai were tightly clustered with strains isolated in the 1990s.Finally,Shaanxi isolates were clustered with strains from adjacent Sichuan.Our results suggest that the rabies cases in emerging and re-emerging areas in China in the last 5 years are a consequence of the epidemic spreading from of neighboring provinces and regions experiencing a serious epidemic of rabies.

BACKGROUND:Transforaminal endoscopic discectomy needs to dissociate the ligamentum flavum, and if
combined with the continuous dilator and working channel, it can keep the intact ligamentum flavum no matter how smal the incision may be (even 3-5 mm).
OBJECTIVE:To present the technique of interlaminar endoscopic lumbar discectomy with ligamentum flavum splitting.
METHODS:We performed operations on 16 male and 14 female patients by interlaminar endoscopic lumbar
discectomy with ligamentum flavum splitting. The average age of the patients in the study was (48±15) years. The chief complaint before surgery was radiculopathy confined to one leg. The anatomic operative level was L 3-4 in
one case, L 4-5 in 13 cases and L 5-S 1 in 16 cases. The ruptured disc migrated superiorly in four cases and
inferiorly in seven cases, and intraoperative electromyo-graphic monitoring was performed in al surgeries. The
ligamentum flavum was split, and after withdrawing the working channel, the ligamentum flavum could reset itself. RESULTS AND CONCLUSION:The total operation time was 20-40 minutes, and the fol ow-up period was
(149±108) days. There were no abnormal signals on the intraoperative electromyography in any cases, and the reported symptoms were immediately improved in al patients after the operation. Fol ow-up magneticresonance imaging showed a disappearance of the ruptured disc without defect in the ligamentum flavum. There were no operation-associated complications in al the patients. Interlaminar endoscopic lumbar discectomy with
ligamentum flavum splitting is a feasible approach.

Objective To investigate the effectiveness of femoral troehanter reconstruction and artificial femoral head replacement in treatment of unstable intertrochanterie fractures in the elderly pa- tients. Methods Femoral trochanter reconstruction and artificial femoral head replacement was done on 106 patients with unstable intertrochanterie fractures. There were 45 males and 61 females, at age range of 80-105 years (average 88 years). Most of patients slipt in the room and got fractured. According to the Evans classification, there were 31 patients with type ⅢA fractures, 45 with type ⅢB and 30 with type IV. We used 4 kinds of methods to reconstruct the fracturad imertrochanters : (1) shape of" ∞ " ten- sion band fixation after intertrochanterie fracture reduction;(2) wire loop fixation of the lesser troehanter around proximal femur;(3)defect within the femoral ealear was filled with bone cement and remodeled; (4) for patients with relative intact base of femoral neck, the intertrochanterie fracture was transformed in- to femoral neck fracture and the femoral ealear was fixed with femoral prosthesis stem. Results All the operations continued successfully, with duration of the operation for 45-70 minutes (average 55 minutes). No artificial femoral head dislocation occurred during hospitalization. Of all, 79 patients were followed up for 6-48 months (average 16 months). No Late loosening, dislocation or infections occurred, with total excellence rate of 87.3%. Conclusions For elderly patient with unstable intertrochanterie fractures, reconstruction of femoral intertrochant and artificial femoral head replacement can restore the proximal femoral anatomy, maintain stability of the hip joint and help early functional exeereise, as can reduce ease fatality rate and improve the quality of life.

OBJECTIVETo explore the effect of Yixintai Granule (YG) on mRNA and protein expression levels of AQP2 in renal medulla of chronic heart failure (CHF) rabbits.

METHODSCHF rat model was established by ear marginal vein injection of adriamycin. Successfully modeled rabbits were divided into the model group, the high (8.4 g/kg), middle (4.2 g/kg), and low dose (2.1 g/kg) YG group, and the Furosemide group (2 mg/kg). Besides, a normal control group was set up. Equal volume of physiological saline was administered to rabbits of the model group and the normal control group by gastrogavage. YG at different doses was administered to rabbits of the 3 YG groups by gastrogavage. The intervention lasted for 4 weeks, once per day. After treatment the urine volume and pathomorphological changes of renal medulla tissue were observed. mRNA and its protein expression levels of AQP2 were detected.

RESULTSCompared with the normal control group, the urine volume decreased significantly, mRNA and protein expression levels of renal medulla AQP2 increased significantly in the model group (all P < 0.01). Compared with the model group, the urine volume increased significantly, and mRNA and protein expression levels of renal medulla AQP2 decreased significantly in all medicated groups (all P < 0.01). Compared with the low dose YG group, the urine volume significantly increased and the mRNA expression level of renal medulla AQP2 significantly decreased in the middle and high dose YG groups (all P < 0.01). The expression level of AQP2 protein significantly decreased in the high dose YG group (P < 0.01). Pathological changes of the renal medulla was the most obviously seen in the model group. But they were alleviated to various degrees in all medicated groups. They were more obviously attenuated in the middle and high dose YG groups.

CONCLUSIONYG could improve CHF possibly through down-regulating mRNA and protein expression levels of AQP2 in renal medulla, and elevating the urine volume.

Animals ; Aquaporin 2 ; genetics ; metabolism ; Chronic Disease ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; therapeutic use ; Heart Failure ; drug therapy ; metabolism ; RNA, Messenger ; metabolism ; Rabbits ; Rats, Sprague-Dawley

ObjectiveTo explore the effects ofYixintaiGranules on expression of C-Myc mRNA and its protein in myocardial tissues of rabbits with chronic heart failure (CHF).Methods CHF rabbit models were established by ear marginal vein injection of adriamycin. Successfully modeled rabbits were divided into the model group, the Losartan Potassium group, the high-, medium-, and low doseYixintaiGranules groups. Besides, a normal control group was set up. Administration groups were given relevant medicine for gavage, equal volume of physiological saline was administered to rabbits of the model group and the normal control group by gastrogavage. The intervention lasted for 4 weeks, once per day. Echocardiographic indexes and mRNA and protein expression levels of C-Myc in myocardial tissue were detected after 4 weeks of medication.Results Compared with the normal group, the LVEF, LVFS, and E/A of the model group decreased significantly (P<0.01), but mRNA and protein expression levels of C-Myc in myocardial tissues increased significantly (P<0.01). Compared with the model group, the LVEF, LVFS, and E/A of YG groups and Losartan Potassium group increased significantly (P<0.01), but mRNA and protein expression levels of C-Myc in myocardial tissues decreased significantly (P<0.05,P<0.01).ConclusionYixintaiGranules can effectively inhibit the expression of mRNA and protein expression of C-Myc, and improve cardiac function.