Objective To investigate the protective effects of metallothionein （MT） for immature myocardium and myocardial interstitium.Methods Twenty-four rabbits （aged 14-21 days） were divided into 4 groups with random number table, 6 each group. Distilled water was injected intraperitoneally in control group and 3.6% ZnSO4 （1.5 ml/kg） was injected intraperitoneally in group 1, group 2 and group 3. Control group, group 1, group 2 and group 3 isolated working rabbit heart model were used in 24h, 12h, 24h and 48h after intraperitoneally respectively. The MT content, recovery of hemodynamics, biochemistry and myocardial ultrastructure were tested. Results The MT content, hemodynamics recovery, adenosine triphosphate （ATP） content, superoxide dismutase activity, Ca2＋-ATPase activity, synthesizing ATP activity of mitochondria, hydroxyproline in group 2 and group 3 were higher than those in control group and group 1 （P 〈 0. 01）. The myocardial watery content, creatine kinase and dehydrogenase leakage, malondialdehyde content, endothelin, mitochondrial Ca2＋ content in group 2 and group 3 were lower than those in control group and group 1（P〈0.01）. The myocardial ultrastructure injuries were less in group 2 and group 3 than that in control group and group l. Conclusion This study demonstrates that myocardial MT prolonged expression can be induced by ZnSO4 and the ischemia-reperfusion injury of immature myocardium and myocardial interstitium could be reduced by MT.
Objective To observe the protective role of the ectogenesis zinc on the cells in rat flap with ischemia reperfusion injury and study the mechanisms. Methods A right low abdominal island flap was created in Wistar rats. Fortyeight rats were randomly divded into 3 groups (n=16):the control group, the ischemia reperfusion group and adding zinc ischemia reperfusion group.The content of malondialdehyde(MDA) and the activity of myeloperoxidase(MPO) were measured by thiobarbituric acid methods and colorimetry. The location of expression of MT was observed,and the image analysis was performed. The quantity of MT was represented by the integratial optical density. The ultrastructure changes of skin flap with ischemia reperfusion injury and the flap viability were observed. Results In the ischemia reperfusion injury flaps, the content of MDA and MPO show no statistically significant difference among the control group,IR group and the adding-zinc-IR group (P＞0.05). Compared with the control group at 1 h and 24 h of reperfusion, the level of MDA increased 62.2% and 136.4%(P＜0.01) in the IR group, which increased 11.3% and 33.2%(P＜0.01) in the adding-zinc-IR group. The activity of MPO increased 238.4% and 503.4%(P＜0.01)in the IR group when compared with the control group, and increased 17.9%and 24.1%(P＜0.05) when compared with the adding-zinc-IR group. In the ischemia reperfusion injury falps, the content of MT in the control group and the IR group is too minimal to measure. While the content ofMT in the adding-zinc-IR group is 45.30±7.60. At 1 h and 24 h of reperfusiion, the content of MT in the adding-zinc-IR group increased 41.5% and 44.9% (P＜0.01) compared with the IR group, and increased 119.9% and 234.6% (P＜0.01) compared with the control group. The flap viability is 100% in the control group, 19.65%±4.38% in the IR group, and 24.99%±5.12% in the adding-zinc-IR group, which increased 27.2% (P＜0.05) compared with IR group. Conclusion Many kinds of cells in skin flap with ischemiareperfusion injury can be protected by ectogenesis zinc and the flap viability increases significantly.
Objective Lots of metal ions accumulation and over-expression of receptor activator of NF-κB l igand (RANKL) around the prosthesis could be found in revision of total hip arthroplasty. To investigate the relationship between metal ions and aseptic loosening by observing the effects of Co2+ and Cr3+ ions on the expression of RANKL and osteoprotegerin(OPG) from osteoblast. Methods Osteoblasts were cultured in vitro at the density of 1 × 105 cells/mL, and were divided into 2 groups according to different culture solutions. In control group, osteoblasts were cultured with normal medium without CoCl2 and CrCl3. In experimental group, osteoblasts were cultured with the medium including CoCl2 (10 mg/ L) and CrCl3 (150 mg/L) solutions. The RT-PCR and ELISA methods were appl ied to detect the mRNA expression of RANKL and OPG and protein level at 24 and 48 hours after co-cultured, respectively. Results RT-PCR revealed that the mRNA expression of RANKL and OPG could be found in two groups at 24 and 48 hours after co-cultured, the expression was higher in the experimental group than in control group, especially the expression of RANKL, showing significant difference (P lt; 0.05). At 24 and 48 hours after co- cultured, the ratios of RANKL mRNA to OPG mRNA in the experimental group were 0.860 and 1.232, respectively, which were significantly higher than those in the control group (0.695 and 0.688,P lt; 0.05). ELISA revealed that the protein level of RANKL and OPG in experimental group were significantly higher than those in the control group (P lt; 0.05). Conclusion Co2+ and Cr3+ can stimulate the mRNA expressions of RANKL, OPG and secretion of those protein from osteoblasts, especially increase of the RANKL, which promotes the formation and activation of osteoblasts and the generation of aseptic loosening.
To investigate the relationship between metallothionein (MT) and prognosis in breast cancer MT expression was determined with immunohistochemical method (SABC). Results: There was a statistically significant association between expression of MT in breast benign and malignant disease (Ｐ＜0.005). The positive rate was 73.8%(62/84) and 15.0%(3/20) in breast cancer and mastofibroma respectively. The positivity of MT was ber in advanced clinical stages than in early clinical stages. There was no association between MT expression and lymph node metastasis. The mortality of the cancer cases with lymph node metastasis having positive MT expression was higher than those with negative MT expression. Conclusion: MT can be taken as a prognostic index of breast cancer.
Objective To observe the human mononuclear cell releasing TNF-α and the activation of Caspase-3 during apoptosis after stimulated by Co2+ and Cr3+, to discuss the mechanism of artificial joint wear production metal ion on aseptic loosening. Methods CoCl2 powder and CrCl3 powder were dissolved by asepsis inject water, preparing solution for10 mg/L and 500 mg/L, respectively. Mononuclear cells were acquired from peripheral blood, 4 × 106/culture dish. According to the difference of culture solution, the cells were divided into 3 groups. Group A: mononuclear cell was culture with normal sal ine as control; group B: mononuclear cell was cultured with CoCl2 solution; group C: mononuclear cell was cultured with CrCl3 solution. The production of TNF-α was assessed by ELISA, the activation of Caspase-3 was measured by colorimetric assay and the apoptotic cell was detected by TUNEL assays at 12, 24 and 48 hours after co-cultured respectively. Results The concentration of TNF-α and the expression of Caspase-3 in groups B and C were higher than those in group A (P lt; 0.05), and reached the peak level at 24, 48 hours, respetively. The TUNEL positive cells were detected in the all groups, nucleus was pyknotic and darker-staining, cell body was crinkle and cell membrane was integrity. There were significant differences in the apoptosis rate between groups B, C and group A (P lt; 0.05). And the activation of Caspase-3 increased and had the positive correlation with the apoptosis rate (r=0.765). Conclusion Co2+ and Cr3+ ions can stimulate human mononuclear cell to release TNF-α and induce human mononuclear cell apoptosis, which result in periprosethetic osteolysis and related to activation of Caspase-3.
Objective To research the clinical characteristics and the arysulfatase A(ARSA) gene screening inafamily withametachromatic leukodystrophy and epilepsy child.
Methods Clinical data were collected and ARSA gene were tested by PCR and Sanger sequencing in the pedigree．
Results Two mutations in exon 2 of ARSA gene was identified in the proband includingaknown heterozygous missense mutation c.293C>T which was also found in his mother andanovel frameshift mutation c.302de1G. None of them was found in the proband’s brother.
Conclusion The intractable epilepsy of the proband was related to his metachromatic leukodystrophy. Andanew frameshift mutation c.302delG was found in his ARSA gene, which haven’t reported around the world yet. Combined with the patient’s typical late infantile presentation, we speculated that the frameshift mutation c.302delG may be the cause of MLD.
In recent years, bone implant materials such as titanium and titanium alloys have been widely used in the biomedical field due to their excellent mechanical properties and good biocompatibility. However, in clinical practice, bacterial adhesion to the material surface and postoperative infection issues may lead to implantation failure. Based on the antibacterial mechanism, this review elaborated on the antibacterial surface design of titanium implants from the aspects of anti-bacterial adhesion, contact sterilization and photocontrol sterilization. Surface modification of titanium or titanium-based alloy implants with different techniques can inhibit bacteria and promote osseointegration. Thus, the application range of multifunctional titanium-based implants in the field of orthopedics will be expanded.
Although metal blocks have been widely used for reconstructing uncontained tibial bone defects, the influence of their elastic modulus on the stability of tibial prosthesis fixation remains unclear. Based on this, a finite element model incorporating constrained condylar knee (CCK) prosthesis, tibia, and metal block was established. Considering the influence of the post-restraint structure of the prosthesis, the effects of variations in the elastic modulus of the block on the von Mises stress distribution in the tibia and the block, as well as on the micromotion at the bone-prosthesis fixation interface, were investigated. Results demonstrated that collision between the insert post and femoral prosthesis during tibial internal rotation increased tibial von Mises stress, significantly influencing the prediction of block elastic modulus variation. A decrease in the elastic modulus of the metal block resulted in increased von Mises stress in the proximal tibia, significantly reduced von Mises stress in the distal tibia, decreased von Mises stress of the block, and increased micromotion at the bone-prosthesis fixation interface. When the elastic modulus of the metal block fell below that of bone cement, inadequate block support substantially increased the risk of stress shielding in the distal tibia and fixation interface loosening. Therefore, this study recommends that biomechanical investigations of CCK prostheses must consider the post-constraint effect, and the elastic modulus of metal blocks for bone reconstruction should not be lower than 3 600 MPa.
Objective Metal wear products cause the aseptic loosening of joint prosthesis. To investigate the effect of metal ions Co2+ and Cr3+ on the osteoblast apoptosis, cell cycle distribution, and secretion of alkal ine phosphatase (ALP), and to search a method to prevent and treat aseptic loosening. Methods The mouse calvarial osteoblasts (MC3T3-E1) were cultured in vitro to 3-5 generations (5 × 105 cells/ mL) and divided into 2 groups: the experimental group and the controlgroup. The osteoblasts were cultured in α-MEM medium containing 10%FBS (the control group), and the mixed solution ofCoCl2 and CrCl3 was added after the osteoblasts cultured in α-MEM medium containing 10%FBS attached completely (the experimental group). At 12, 24, and 48 hours after culture, the osteoblast apoptosis and the cell cycle distribution were assessed by flow cytometry; and ELISA method was appl ied to detect ALP content in serum supernatant. Results At 12, 24, and 48 hours after culture, the apoptosis rates in the experimental group (13.90% ± 0.52%, 14.80% ± 0.41%, and 13.40% ± 0.26%) were significantly higher than those in the control group (8.56% ± 0.31%, 8.19% ± 0.24%, and 2.15% ± 0.11%), (P lt; 0.05); G2M (dividing phase) distribution ratio significantly decreased and G0G1 (dormancy stage) distribution ratio significantly increased when compared with those in the control group (P lt; 0.05); and the absorbency (A) values of ALP were 0.955 ± 0.052, 0.624 ± 0.041, and 0.498 ± 0.026 in the exprimental group, and were 1.664 ± 0.041, 1.986 ± 0.024, and 2.192 ± 0.041 in the control group, showing significant differences between 2 groups (P lt; 0.05). Conclusion Metal ions Co2+ and Cr3+ have a marked effect on osteoblasts cell cycle distribution, which can make most of the cells to be in dormancy stage (G0G1), up-regulate the apoptosis rate and inhibit the releasion of ALP from osteoblasts.
Objective To compare advantage and disadvantage of internal fixation method for tibia intercondylar eminence fracture between absorbable screw and metallic screw. Methods From 1996 to 2002, 200 patients with fracture of tibia intercondylar eminence were divided into group A (with absorbable screw, n=120) andgroup B (with metallic screw, n=80). And the biological compatibility, biomechanics, bone union and complications were compared between two groups.Results There were no obvious differences in operating time and circumstance of recovery position between two groups. Group A was obviously better than group B in biological compatibility, biomechanics, bone union, joint function recovery. The average healing time of group A was three months, that of group B was three and half months. The good rates of joint function in two groups were 98.0% and 95.0% respectively. The occurrence rates of wound arthritis were 1.7% and 3.7%. There wassignificant difference between them(P＜0.01). Conclusion Absorbable screw is a more ideal material of internal fixation to treat tibia intercondylar eminence fracture.
