BACKGROUND:At present, the clinical treatment of lumbar disc degeneration mainly includes conservative treatment, traditional surgery and minimal y invasive surgery. The therapeutic purpose is to relieve symptoms, but the long-term effect is not very satisfactory. Therapeutic methods focusing on biological functional recovery have been concerned gradual y, but the clinical application is far in sight. OBJECTIVE:To review the advances in the treatment of lumbar disc degeneration regarding tissue-engineered repair and biomechanics. METHODS:PubMed database was searched by the first author for relevant articles published before December 2014 using the keywords of“intervertebral disc degeneration, clinical treatment, biological treatment, tissue engineering, biomechanics, repair, progress”in English. A total of 100 articles were searched initial y and final y, 40 articles were included in result analysis. RESULTS AND CONCLUSION:Although the therapeutic schemes are varied, the treatment of intervertebral disc degeneration is a great chal enge for clinicians and basic researchers. Currently there is no perfect clinical treatment, and indications corresponding to various therapies should be paid attention as wel as long-term fol ow-up evaluation. For various reasons, the biological treatment for intervertebral disc degenerative disease is becoming more and more popular, providing a promising prospect for the treatment of intervertebral disc degeneration. So far, large amounts of data have been obtained from animal experiments, but there are stil many problems to be solved. Other chal enges also involve the al aspects of general tissue engineering methods, such as cel s, cytokines and scaffolds. In these studies, the nucleus pulposus tissue engineering based on the combination of heparin-functionalized chitosan hydrogel, cytokines and stem cel s exhibits a promising prospect.

BACKGROUND:None of the current treatment strategies has been focused on relieving or reversing the disk degeneration process after degenerative disc diseases. In recent years, more and more scientists try to treat degenerative disc diseases using stem cel therapy. OBJECTIVE:To explore the research status and prospects of stem cel therapy for degenerative disc diseases. METHODS: A computer-based online search of PubMed database between January 2004 and December 2014was performed to search related articles with the key words of “stem cel, intervertebral disk” in English. Literatures related to stem cel therapy for degenerative disc diseases were selected; in the same field, the articles published lately in authoritative journals were preferred. RESULTS AND CONCLUSION: A total of 342 articles were primarily selected, and 43 articles were involved in result analysis according to inclusion criteria. Stem cel therapy is a newly treatment for degenerative disc diseases. Cels appropriate for stem cel therapy include embryonic stem cels, induced pluripotent stem cels, mesenchymal stem cels, human umbilical cord mesenchymal stem cels and chondrocytes or nucleus pulposus cels. Although cel leakage, intervertebral disc infection and tumorigenesis are the main chalenges, stem cel therapy for degenerative disc diseases is promising in the future.

AIM:To detect and compare the longitudinal mitral annulus diastolic velocity and time interval changes by pulsed Doppler tissue imaging(DTI)in patients with angina pectoris(AP)and myocardial infarction(MI),and to explore the value of mitral annulus diastolic velocities and time intervals for evaluation of global left ventricular diastolic dysfunction.METHODS:Fifty patients with established coronary artery disease were divided into AP group(16 cases)and MI group(34 cases).Sixteen age-matched healthy individuals served as the control group.The septum,lateral,anterior and inferior walls of the mitral annulus were displayed,and selected for DTI spectrum sampling.Peak early and late diastolic velocities and their ratio,time to the onset and peak of the early diastolic wave,and regional isovolumic relaxation time were measured,and the average values of the four mitral annular sites were calculated and presented as Em,Am,Em/Am,QEm,TEm and IVRTm,respectively.RESULTS:Compared with the control group,Em and Em/Am were significantly lower in both the AP and the MI groups(P＜0.01).Em was even lower in the MI group than that in the AP group(P＜0.01).QEm,TEm and IVRTm were significantly longer in the AP and the MI groups than those in control group(P＜0.01 or P＜0.05).IVRTm was even longer in the MI group than that in AP group(P＜0.01).IVRTm had significantly negative correlation with Em(r=-0.64,P＜0.01).CONCLUSION:Em,Em/Am,QEm,TEm and IVRTm as measured by pulsed DTI may be promising indexes for quantitative assessment of global left ventricular diastolic dysfunction in patients with coronary artery disease.Em and IVRTm may indicate the severity of ischemic myocardial damage.

AIM: To investigate the effect of peroxisome proliferator-activated receptor ? (PPAR?) activator rosiglitazone on myocardial ischemic-reperfusion injury in rats. METHODS: Forty-two SD rats were randomly divided into three groups: sham group (n=14), I/R group (n=14) and I/R+rosiglitazone group (n=14). Myocardial infarct size was assessed by NBT staining. Plasma and myocardial angiotensin and aldosterone as well as plasma renin activity were detected by radioimmunoassay. RESULTS: Compared with I/R group, myocardial infarct size was reduced by 23.9% (P

Objective To explore the mechanism of Didang Qigui Recipe on preventing diabetes. Methods Ten female rats were set randomly as normal group, and others 70 were injected with STZ (60 mg/kg) to establish the diabetic model. After the model was established, 50 model rats were randomly divided into five groups:the model group, Didang Qigui Recipe group, the gliclazide group, Didang Qigui Recipe high-dose group, Didang Qigui Recipe and gliclazide group, with 10 rats in each group. All groups were given a gavage with related medicine. With treatment being given respectively, eight weeks later, contents of IL-1βand IL–2 in serum were detected by ELISA and structure of pancreatic β cells was observed by immunohistochemistry and microscope. Results Compared with the model group, the contents of IL-1βand IL-2 in serum of rats decreased in treatment groups, especially in Didang Qigui Recipe group and Didang Qigui and gliclazide group (P<0.05). The degree of apoptosis in pancreaticβcells, especially in the above two groups, has been less affected than other groups (P<0.05). Conclusion Didang Qigui Recipe has preventive and therapeutic effects on diabetes by inhibition of inflammatory response and protection structure of pancreaticβcells.

AIM: To study the differentiation of rat bone mesenchymal stem cells (MSCs) into cardiomyocytes in vitro. METHODS: MSCs were isolated and purified from the bone marrow of rats by density gradient centrifugation and adhering to the plastic culture. The third passage MSCs were treated by 5-azacytidine (5-aza). The induced cells were evaluated by immunocytochemistry staining and RT-PCR analysis. RESULTS: After being induced by 5-aza, some MSCs became bigger and longer. The connection of the cells were formed on day 14.The direction of the cells arraying was similar gradually. The induced cells were stained positively for desmin, ?-actin and troponin I. RT-PCR showed that these cells expressed ? myosin heavy chain. CONCLUSION: 5-aza can induce MSCs to differentiate into cardiomyocytes in vitro.

AIM: The aim of this study was to investigate the possibility of establishing a chronic atrial fibrillation model with long-term rapid atrial stimulation ( 1 000 bpm), which was performed in rabbits in vivo. METHODS: 20 rabbits were randomly divided into 2 groups: 1) control group (n=10): pacemaker was implanted but no pacing; 2) experimental group (n=10): a left intercostal thoracotomy was performed and the pericardium was opened to expose the heart and a steel-wire pacing electrode was fixed on the epicardium of the left atria in 10 rabbits. Then the rapid pulse generator was implanted subcutaneously in the left abdominal region and rapid atrial pacing ( 1 000 beats/min) was initiated and continued for 30 days. Electrocardiogram (ECG) was monitored and recorded on day 1, 3, 5, 7, 14, 21 and 30. The atrial effective refractory period (AERP) was measured before pacing and at the time of fibrillation. RESULTS: On day 14, atrial fibrillation was developed in 8 rabbits (80%) and sustained at least till to day 30 (P

0.05). In the non-smoking group, the pulse pressures of patients with coronary heart disease were significantly higher than those of subjects with negative angiographic results. Among the three subgroups with different severity of coronary arterial lesion, the pulse pressure of 3-vessel diseases was higher than those of both 2-vessel and 1-vessel subgroup. The pulse pressure of subjects with negative angiographic results in smoking group was significantly higher than that in non-smoking group [(56.1?17.2) mm Hg vs (50.9?11.4) mm Hg,1 mm Hg=0.133 kPa P

AIM: To investigate the relations between the proliferation and phenotype change of adventitial cells and the expression of T GF-?1 in adventitia after arterial injury. METHODS: After abdominal artery injury in rabbits, adventitial cel l proliferation and phenotype were identified by immunohistochemistry, transmissi on electron microscope and in situ Hybridization. RESULTS: Three days and 7 days after injury, the PCNA-positive ce lls were significantly increased. The previously weakly actin-positive adventiti al cells became strong-actin staining, the typical myofibroblast featurses of ad ventitial cells were detected by TEM 7 and 14 days after injury. Three days afte r vascular injury, there was a marked increase in the nu mber of cells that demonstrated the presence of TGF-?1 transcripts within the adventitia. Seven days after arterial injury, adventitial cells continued to ex press TGF-?1. on day 28, the number of TGF-?1-expressing cells was markedly r e duced in the adventitia. CONCLUSION: This study demonstrates that the proliferation and p henotype modulation of adventitial cells are associated with induction of TGF- ?1 expression in adventitia after arterial injury.

BACKGROUND: Currently, the morphologic characteristics of the torn discoid lateral meniscus remain unclear, andmorphological indexes used to evaluate the discoid lateral meniscus tears still need to be explored. OBJECTIVE: To discuss the specificity and sensitivity of discoid lateral meniscal tears in children using morphological indexes. METHODS: Seventy-three patients (seventy-six knees) with torn discoid lateral meniscus underwentarthroscopy and MRI data of knee examinations were retrospectively reviewed. All MR images were double-blinded, independently, retrospectively analyzed by attending radiologist (doctor A) and sports physician (doctor B). The following morphological signs of discoid lateral meniscus, such as a internal displaced free edge sign, a hypertrophic free edge sign and a hypertrophied-horn sign, were selected to evaluate the discoid lateral meniscus tears. The likelihood of the discoid lateral meniscus tears was analyzed on basis of arthroscopic findings constituted the gold standard. Sensitivity, specificity and accuracy of MRI diagnosis of the discoid lateral meniscus tears by two physicians were calculated, and the consistency of diagnosis results by two physicians was evaluated using the Kappa statistics.RESULTS AND CONCLUSION: (1) The sensitivity, specificity and accuracy in the diagnosis of discoid lateral meniscustears by internal displaced free edge sign for doctor A were 19%, 94% and 53%, respectively, and for doctor B were 21%, 97% and 55%. (2) The sensitivity, specificity and accuracy in the diagnosis of discoid lateral meniscus tears by hypertrophic free edge sign for doctor A were 52%, 100% and 74%, respectively, and for doctor B were 57%, 97% and 75%. (3) The sensitivity, specificity and accuracy in the diagnosis of discoid lateral meniscus tears by hypertrophied-horn sign for doctor A were 26%, 97% and 58%, respectively, and for doctor B were 24%, 100% and 58%. (4) The sensitivity, specificity and accuracy in the diagnosis of discoid lateral meniscus tears by binding morphological index for doctor A were 86%, 91% and 87%, respectively, and for doctor B were 88%, 94% and 91%. (5) The Kappa statistics for discoid lateral meniscus tears respectively demonstrated a good inter-observer agreement (K > 0.75, P < 0.001). (6) These findings suggest that single morphological index used to evaluate the discoid lateral meniscus tears shows a good specificity, but which also shows a low sensitivity, while a binding morphological index can significantly improve the diagnostic sensitivity. Morphological characteristics may be reliable indexes to evaluate the discoid lateral meniscal tears in children.