BACKGROUND: A new material of porous carbonated hydroxyapatite cement (PCHC) is discovered using foaming technique.The new material characterizes original solidification and forms porous structure.OBJECTIVE: To investigate the biomechanical effect of PCHC on repairing cancellous bone defect.METHODS: Among 30 New Land rabbits, 25 ones were considered as surgery group, whose bilateral condyles of femur was used to establish bone defect model (5.5 mm diameter and 12 mm depth). PCHC was implanted into the left side, which was considered as the experimental group, and carbonated hydroxyapatite cement (CHC) was implanted into the right side, which was considered as the control group. Another 5 rabbits were used as normal mechanical control group. Both PCHC and CHC were dip in simulated body fluid (SBF) to test mechanical intension. PCHC and CHC were then implanted into muscles of back in the surgery group. Rabbits Were-sacrificed after 2, 4, 8, 12, and 16 weeks postoperatively. Mechanical analysis was tested following intra-bone and intramuscular implantation, and compressive strength was then tested following dipping into SBF.RESULTS AND CONCLUSION: PCHC: Intra-bone mechanical strength was lower at 2 weeks, the lowest at 4 weeks, but then closed to intension of normal cancellated bone at 8 weeks, higher than normal cancellated bone at 12 weeks, and recovered to the level of normal cancellated bone at 16 weeks. CHC: Intra-bone strength was higher than that of PCHC at 2 weeks, decreased at 4 weeks, gradually increased at 8, 12, and 16 weeks, but still lower than intension of normal cancallated bone. Compressive strength of both PCHC and CHC was not changed following dipping in SBF; however, compressive strength was changed remarkably following intramuscular implantation. The results demonstrated that PCHC characterized by immobilization in situ and mechanical supporting. Thus it could be used for one kind of bone substitute material to repair the bone defect.

AIM: RNAⅢ inhibiting peptide (RIP) has been previously proved to possess good histocompatibility and safety for preventing and curing staphylococcal infection, and this study evaluated histocompatibility of polyaiticglycolic acid/RIP (PLGA/RIP) sustained release microsphere. METHODS: The experiment was performed in the Orthopedic Institute, Pharmacologic Research Institute and Animal Experimental Center of General Hospital of Chinese PLA from October 2005 to October 2007.①Preparation of PLGA/RIP: The solid-phase synthesis (Fmoc) method was used to synthesize RIP from C end to N end, then the synthesized peptide was purified by the reverse phase high performance liquid chromatography, and composition was collected by means of ultraviolet absorption peak. The purified RIP was obtained after freezing and drying. Liquid-phase multiple emulsion method was used to synthesize PLGA/RIP microsphere of 50-70 ?m diameter.②Acute general toxicity test was studied in PLGA/RIP. Effect of PLGA/RIP on the cell proliferation was detected with cytotoxicity test by MTT method. Intramuscular implanting test was used to observe the irritation reaction of muscles by implantation materials. Sensitivity test was used to observe the sensitization of PLGA/RIP. Changes of animal's body temperature were determined with pyrogen test. RESULTS: ①Acute general toxicity test: Neither toxicosis reaction nor animal death was found after animals were injected with 100% and 50% eluents of PLGA/RIP peritoneally. Animal's body weight was not changed significantly.②Cytotoxiciity test by MTT method: The average proliferation rate of cell in two kinds of eluents exceeded 85% and cytotoxicity was graded in 1 rank, indicating no cytotoxicity.③Intramuscular implanting test: At 4 weeks after RIP and PLGA/RIP were implanted into the animals, there was not obvious synathresis, denaturation or necrosis in tissues. No inflammatory cell infiltration occurred around the materials. There had been the fibrous capsules around the materials.④Sensitivity test: Average primary irritation index of three groups were 0.38, 0.33 and 0.31 respectively. There was no significant difference among three groups.⑤Pyrogen test: Fervescence of each animal in the experiment was under 0.5 ℃, confirming that the materials had no pyrogenic characteristics. This was in coincidence with evaluation criterion of pyrogen test. CONCLUSION: PLGA/RIP has good histocompatibility and safety, without general toxic reaction, cytotoxicity, immunological rejection, hypersensitive response or pyrogenic characteristics.

Objective The aim of this study was to investigate the effect of ultrasonically activated hematoporphyrin on ultrastructure of ehrlich ascites tumor(EAT) cells and to evaluate the potential mechanism of action inducing this cytotoxicity. Methods EAT cells in vitro were exposed to ultrasound at 2^0?MHz and 1^5?W/cm+2 for 3?min in the presence or absence of hematoporphyrin.The changes of ultrastructure of sample preparation for different time were observed by transmission electron microscope. Results The degree of destruction of treated EAT cells was enhanced with the increasing of time for the sample preparation.The sites destroyed mainly involved cell membrane,mitochondrion,endoplasmic reticulum and cell nuclei.Furthermore,morphoiogical characters of ultrasound-activated hematoporphyrin induced apoptosis were observed on EAT cells.Conclusion The killing of tumor cells was ascribed mainly to the damage of ultrastructure induced by ultrasound in combined with hematoporphyrin,apoptosis was also induced during ultrasound and hematoporphyrin killing process.;

Objective: To study the effect of and possible mechanism of knockinng down PI3Kp85α using siRNA in MCF-7 human breast cancer cell line. Methods: Oligofectamine was used to transfect PI3Kp85α siRNA to knock down the PI3Kp85α expression level in MCF-7 human breast cancer cell line in vitro. Real-time PCR was conducted to detect the expression of PI3Kp85α. The effect of PI3Kp85αsiRNA on the growth of MCF-7 cells was measured by MTT. The cell cycle distribution and cell apoptosis were detected by cell flow cytometry. Protein expression was evaluated by immunofluorescence staining and Western blot. Results: The expression of PI3Kp85 α was knocked down with PI3Kp85α siRNA in MCF-7 cells. Cell growth was delayed in PI3Kp85αsiRNA-treated group. Conclusion: The suppressive effect of PI3Kp85αsiRNA on the growth of MCF-7 human breast cancer cell line is significant and PI3Kp85α could be a candidate for gene therapy for breast cancer.

[ ABSTRACT] AIM: To investigate the protective effect of autophagy on oxidized low density lipoprotein ( ox-LDL)-induced macrophage apoptosis and the underlying molecular mechanisms .METHODS:The RAW264.7 macropha-ges were pretreated with 3 mmol/L 3-methyladenine (3-MA), 1 μmol/L rapamycin (Rap) or 4 mmol/L 4-phenylbutyric acid ( PBA) respectively for 1 h and then treated with ox-LDL (100 mg/L) for 12 h.The cell viability and apoptosis were determined by MTT assay and flow cytometry with Annexin V-FITC/PI staining, respectively.The activities of lactate de-hydrogenase ( LDH) in the medium and caspase-3 in the cells were determined by detection kits .The protein levels of bec-lin-1 (a molecular marker of autophagy ), glucose-regulated protein 78 (GRP78, an endoplasmic reticulum stress marker) and C/EBP homologous protein ( CHOP, a key-signaling component of endoplasmic reticulum stress-induced apoptosis ) were examined by Western blot .Microtubule-associated protein 1 light chain 3 (LC3, another molecular marker of autoph-agy) was observed under laser scanning confocal microscope .RESULTS: Treatment of the RAW264.7 macrophages with ox-LDL at 100 mg/L for 12 h resulted in significant decrease in cell viability , and dramatic elevation in LDH leakage , cell apoptosis and caspase-3 activity, which were promoted by 3-MA (an autophagy inhibitor) and inhibited by Rap (an autoph-agy inducer ) .ox-LDL induced autophagy in the macrophages as assessed by beclin-1 upregulation and frequent granulation of LC3, which were inhibited by 3-MA and promoted by Rap.Interestingly, 3-MA enhanced, while Rap blocked, the CHOP upregulation induced by ox-LDL.Moreover , PBA ( endoplasmic reticulum stress inhibitor ) significantly inhibited ox-LDL-induced GRP78 upregulation and autophagy as determined by the attenuation of beclin-1 upregulation and frequent granula-tion of LC3.CONCLUSION: Endoplasmic reticulum stress mediates ox-LDL-induced autophagy in macrophages , and moderates activation of autophagy may protect macrophages from ox-LDL-induced apoptosis by inhibiting CHOP expression .

OBJECTIVETo study the clinical results of metal on metal hip resurfacing arthroplasty for developmental dysplasia patients.

METHODSFrom March 2005 to December 2006, 34 cases of developmental dysplasia patients (Crowe I, Crowe II) were attempted to have metal on metal hip resurfacing arthroplasty. There were 29 females (32 hips), 5 males (5 hips). The average age was 45 (26 - 57) years old. Radiographic and clinical evaluations were taken at 6 weeks, 3 months, 1 year and then once a year postoperatively. The average Harris score was 35 (25 - 44). Hip flexion was 101 degrees , abduction 24 degrees , adduction 15 degrees .

RESULTSThree patients were turned to total hip arthroplasty during operations. Thirty-one patients (34 hips) received hip resurfacing surgery. These 31 patients were followed for average 21.4 months (12 - 33 months). The average Harris score was 94 (82 - 100) at the latest follow-up, and there was statistical difference compared with the preoperative score (P < 0.01). Hip flexion increased to 133 degrees , abduction to 48 degrees , adduction to 26 degrees . No radiolucency line was found at both acetabular and femoral sides in all the patients. The average abduction angle of acetabular cup was 43 degrees (40 degrees - 53 degrees ), and the average stem shaft angle was 139 degrees (130 degrees - 145 degrees ).

CONCLUSIONSThe short term result is excellent. While the mid to long term results for hip resurfacing arthroplasty in developmental dysplasia patients are still looking forward, and the meticulous surgical technique and strict patient selection are the key of the good results.

Adult ; Arthroplasty, Replacement, Hip ; methods ; Female ; Follow-Up Studies ; Hip Dislocation, Congenital ; surgery ; Hip Prosthesis ; Humans ; Male ; Middle Aged ; Treatment Outcome

OBJECTIVETo explore the biomarkers of manganese exposure by measuring the manganese (Mn) and iron (Fe) level as well as the mRNA change of Hepcidin, divalent metal-ion transporter-1 (DMT1) and Parkin-2, one of genes related to Parkinson disease in body fluid and brain tissues of rat.

METHODSMale Sprague-Dawley rats were administered (i.p) either MnCl2 solution (6 mg Mn/kg) or the same volume saline, 5 times per week and for 4 weeks. Graphic furnace Atom Absorption Spectrum (AAS) was applied to measure the concentration of Mn and Fe in brain tissue and body fluids. Meanwhile Hepcidin, DMT1 and Parkin-2 mRNA expression were detected by real-time RT-PCR.

RESULTSMn concentration in erythrocytes of rats was the 86.9 folds of that in control; No significant change was found in plasma. However the trend and range of Mn increase in cerebrospinal fluid (CSF) was the same as that in brain tissue including striatum, cortex, hippocampus and choroid plexus. Meanwhile Fe concentration in brain tissue of Mn exposed rats was also higher than that of control, whose trend was as same as that in CSF. However iron concentration in plasma decreased. The real-time RT-PCR data also showed that Hepcidin mRNA expression in Mn-exposed rat decreased 56% in blood, which was in line with its expression in cortex(67%). Similarly, Parkin-2 mRNA expression decreased both in blood (42%) and in striatum. However DMT1 mRNA expression increase 38% in striatum of Mn-exposed rats but decreased in blood.

CONCLUSIONHepcidin and Parkin-2 mRNA expression in blood might be serves as the effective biomarkers following manganese exposure, certainly which needs to be further explored.

Animals ; Antimicrobial Cationic Peptides ; genetics ; metabolism ; Cation Transport Proteins ; genetics ; metabolism ; Corpus Striatum ; metabolism ; Environmental Exposure ; Gene Expression Regulation ; Hepcidins ; Iron ; blood ; cerebrospinal fluid ; Male ; Manganese ; blood ; cerebrospinal fluid ; RNA, Messenger ; genetics ; Rats ; Rats, Sprague-Dawley ; Ubiquitin-Protein Ligases ; genetics ; metabolism

OBJECTIVETo observe the effect of pioglitazone on hypoxia/reoxygenation injury and the expression of protein kinase C (PKC) in neonatal rat cardiomyocytes.

METHODSNeonatal Sprague-Dawley rat cardiomyocytes in primary culture were treated with pioglitazone or GW9662 for 24 h prior to hypoxia/reoxygenation injury. Cardiomyocyte apoptosis was evaluated with Hoechst33258 staining and the expression of PKC was detected using Western blotting.

RESULTSIn the early stage of hypoxia/reoxygenation injury, the apoptosis rates of the cardiomyocytes increased significantly from (0.20∓0.03)% of the control level to (12.22∓1.45)% (P<0.05). Pretreatment with pioglitazone significantly lowered the apoptosis rate of the cardiomyocytes with hypoxia/reoxygenation injury to (8.32∓0.89)%, and this effect was antagonized by GW9662, a specific blocker of peroxisome proliferators activated receptors γ (PPARγ). Pioglitazone did not cause increased expression of PKC in the cardiomyocytes.

CONCLUSIONPioglitazone can ameliorate neonatal rat cardiomyocyte injury induced by hypoxia/reoxygenation partially by activating PPARγ and does not increase the expression of PKC in the cells.

Animals ; Animals, Newborn ; Apoptosis ; drug effects ; Cell Hypoxia ; physiology ; Female ; Ischemic Preconditioning, Myocardial ; methods ; Male ; Myocardial Reperfusion Injury ; physiopathology ; prevention & control ; Myocytes, Cardiac ; enzymology ; pathology ; PPAR gamma ; metabolism ; Potassium Channels ; metabolism ; Primary Cell Culture ; Protein Kinase C ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Thiazolidinediones ; pharmacology

OBJECTIVETo research effect of Wuzhuyu on Huanglian intestinal absorption and to provide some basic principle of match-pair of huanglian-rougui.

METHODThe rat everted gut sac method as well as non everted gut sac method was applied to investigate the influence of Wuzhuyu on Huanglian intestinal absorption.

RESULTThe content of each alkalis in Huanglian was decreasing with the comptibale ration increase, and the intestinal absorption had been improved in some degree. The intestinal absorption of Huanglian alkalis reached the highest level when match-pair ration of huang Lian-rougui was 6: 1.

CONCLUSIONThe chemical reaction in the progress of extraction and the intestinal absorption of huanglian alkalis were the key factors of match-pair of huanglian-wuzhuyu.

Animals ; Drugs, Chinese Herbal ; pharmacokinetics ; pharmacology ; In Vitro Techniques ; Intestines ; drug effects ; Male ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo evaluate the short term clinical results of minimally invasive total knee arthroplasty (MIS-TKA) through a quadriceps sparing (QS) approach compared with a standard TKA using a medial parapatellar exposure.

METHODSBetween March 2005 and March 2006, 26 consecutive unilateral primary MIS-TKA through a QS approach were performed. It was compared that the short term clinical results of this group with an age-matched and sex-match cohort of total knee arthroplasty done with a standard medial parapatellar approach. Length of incision, tourniquet time, blood loss, flexion degree, visual analog scale (VAS) score, Knee Society score, tibiofemoral angle and the ability to do a straight leg raising maneuver were evaluated respectively.

RESULTSThe mean follow-up time were 17 months (range 12-23 months). The average length of incision was (9.5+/-1.5) cm in the QS group and (14.0+/-2.3) cm in the standard group (P<0.05). Average tourniquet times were (83+/-16) minutes in the QS group and (55+/-11) minutes for the standard group (P<0.05). Postoperative tibiofemoral angles averaged (5.7+/-1.5) degrees valgus in the QS group knees and (6.0+/-1.4) degrees valgus in the standard group knees (P>0.05). The average VAS scores were significantly lower at the first, the third and the seventh postoperative days in the QS group compared with that of the standard group, and the difference was not significant after 6 weeks between two groups. Mean flexion at one week was greater for the QS group (107+/-12) degrees than that in the standard group (95+/-11) degrees. Improved ROM also was seen 6 and 12 weeks postoperatively in the QS group with significant difference. There were no differences in ROM between the two groups in 12 months. The ability to straight leg raised at one week postoperatively was better in the QS group (23/26, 88%) than that of the standard group (21/33, 64%). At the 6 weeks follow-up, the average knee score was (78+/-15) points in the QS group and (71+/-20) points for the standard group (P<0.05). Deep vein thrombosis were found in 1 case of the QS group and 3 cases for the standard group. One patient in the QS group developed superficial wound necrosis that healed uneventfully. There were no other complications such as deep infection, neurovascular injury and so on.

CONCLUSIONSThe MIS-TKA through a QS approach is associated with a more rapid functional recovery and improves range of motion. But higher specifications and more restrictive indications are of importance with the QS technique.

Arthroplasty, Replacement, Knee ; methods ; Follow-Up Studies ; Humans ; Minimally Invasive Surgical Procedures ; methods ; Quadriceps Muscle ; Treatment Outcome