Comparative study on Sichuan yak pericardium and Australian cattle pericardium / 生物医学工程学杂志

Currently, as the key raw material of artificial biological heart valve, bovine pericardium is mainly depend on import and has become a "bottleneck" challenge, greatly limiting the development of domestic biological heart valve. Therefore, the localization of bovine pericardium is extremely urgent. In this study, the pericardium of Sichuan yak was compared with that of Australian cattle in terms of fundamental properties and anti-calcification performance. The results demonstrated that the appearance and thickness of yak pericardium were more advantageous than the Australian one. Sichuan yak pericardium and Australian cattle pericardium had comparable performance in shrinkage temperature, mechanical test and anti-calcification test. This study preliminarily verifies the feasibility of substitution of Australian cattle pericardium by Sichuan yak pericardium and promotes the progression of bovine pericardium localization with data support.

The impact of the loss of attachment in Hirayama disease patients treated with anterior cervical discectomy and fusion / 中华骨科杂志

Objective　To investigate the impact of the loss of attachment on the outcomes in Hirayama disease(HD)patients treated with anterior cervical discectomy and fusion(ACDF).Methods　A total of 26 patients(23 males and 3 females)who were diagnosed as HD and received 2 levels of ACDF surgery from February 2014 to November 2016 were enrolled in the present study.All patients took the MRI at both flexion and neutral position pre-operation and MRI at flexion position post-operation.The measured parameters related to performance of "loss of attachment" include:the distances between the posterior edge of the spinal cord and the cervical spinal canal(x),the anterior and posterior wall of the cervical spinal canal(y),the anterior-posterior(a)and the transverse diameter(b)of spinal cord cross sections.The value of the cervical spinal cord deformation(flexion position a/b)and the cervical spinal cord forward movement(flexion position x/y-neutral position x/y)were calculated,and the centrums refer to the performance of "loss of attachment" were also recorded.DASH scores and grip strength on both sides were recorded before and 1 year after operation.The 26 patients were divided into two groups,17 patients(17/26,65.4%)in improvement group with the decreased DASH scores and the other 9 patients(9/26,34.6%)in no improvement group.Logistic regression and ROC curve were used to analyze the influence factor of anterior cervical discectomy and fusion(ACDF)surgery on patients with Hirayama disease.Results　After surgery,the value of a/b significantly increased(t=4.27,P=0.001)and x/y significantly decreased(t=10.25,P=0.001).The performance of "loss of attachment" in 88.5%(23 of 26)patients disappeared after surgery,while the DASH score(P=0.06),and the grip strength of severe and mild side(P=0.36 and P=0.42)shew no obvious change.65.4%(17 of 26)patients shew a decrease in DASH scores after operation,the remaining 34.6%(9 of 26)patients shew no obvious change,several even with a mild increase.The segments refer to performance of "loss of attachment",the value of the cervical spinal cord de-formation and the cervical spinal cord forward movement shew a difference between the two group(t=-5.56,P=0.001;t=3.06,P=0.005;t=-3.76,P=0.001).The logistics regression analysis with the above three independent variable confirmed that the value of segments that refer to "loss of attachment" was the factor of the post-operative efficacy of ACDF surgery on patients with Hirayama disease(OR=6.963,P=0.001).And the ROC curve shew AUC=0.902,Jordan index=0.83,critical value=4.5.Conclusion　The anterior cervical discectomy and fusion(ACDF)surgery can effectively improve the loss of attachment at the surgical segments,and prevent the progress of upper limb dyskinesia.And range of the longitudinal separation refers to "loss of attachment" can impact the outcomes of ACDF surgery,more segments for fusion may be need in order to improve the outcomes of those patients with the range more than 5 segments.

Preparation of hydroxyapatite in the presence of amino acids by hydrothermal method / 国际生物医学工程杂志

Objective To investigate the preparation method of hydroxyapatite by amino acids induced hydrothermal technique.Methods The hydroxyapatite nanorods were obtained using alanine and glycine as templates by hydrothermal method.The samples were characterized by X-ray diffraction (XRD),Fourier infrared spectroscopy (FTIR),transmission electron microscopy (TEM).Results The results showed that amino acids induced the formation of hydroxyapatite.Amino acids could affect crystallinity and dispersion of the formed hydroxyapatite.In addition,the substituent content of carbonate ions in hydroxyapatite was reduced by changing the ratio of amino acids.Conclusion Hydroxyapatite with high crystallinity and low carbonate ions can be prepared by hydrothermal method in the presence of amino acids.

In vivo and in vitro studies on anode-oxidized titanium percutaneous implants / 生物医学工程学杂志

In order to solve the problesm in biological sealing of load-bearing percutaneous implants for a fairly long time, we investigated titanium with bioactivated anodic oxidized surface(group A) through the animal tests in vivo and the epithelium cell culture in vitro. Smooth Ti (group B) was used as control. The animal tests results showed that there was no evident difference in the inflammory reaction between the group A implant tissues and the group B implant/tissues. The bioactivated Ti surface could keep the implant not only bonding with the bone firmly but also adhering to the soft tissue closely, thus contributing to the formation of calcium phosphate layer and its micropores. The cell culture results also demonstrated that the microporous surface of group A could clasp and fix the skin. So, it can be concluded that the surface modified method of anode oxidization may be one of the most effective methods to resolve the problem of durable biological sealing.