BACKGROUND:Currently, the cement delivery device used in vertebral augmentation vertebral augmentation (vertebroplasty and kyphoplasty) has flat tips that cannot be bent. During surgery, we always choose injection cement by symmetric way to keep the balance of power on the biomechanics of the vertebral body, while the traditional cement delivery tube can only be used in ipsilateral vertebral body.
OBJECTIVE:To evaluate the feasibility of curved vertebroplasty device for the treatment of thoracolumbar osteoporotic vertebral compression fractures.
METHODS: Sixty patients (72 vertebral bodies) with osteoporotic vertebral compression fractures were enroled, including 8 cases of double-level vertebral fractures and 2 cases of three-level vertebral fractures. Al operations applied curved delivery device in percutaneous vertebroplasty. We recorded operation time, intraoperative blood loss, and X-ray imaging data through prospective self control study. Treatment effect was evaluated with modified Oswestry disability index, Visual Analogue Scale scores and the World Health Organization Quality of Life assessment. The patients were folowed up for 6 months to 2 years.
RESULTS AND CONCLUSION: (1) Surgery was performed successfuly on al 60 patients. The average operation time was 27 minutes (20-45 minutes) for 50 cases by unilateral transpedicular approach. (2) The mean amount of bone cement in every single vertebral of al 72 vertebrae was averagely 6.4 mL (4.2-9.5 mL). Bone cement distribution had not been found to be biased one-sided without severe leakage. (3) Visual Analogue Scale score and Oswestry disability index were significantly improved at 1 day after treatment (P < 0.05). During the final folow-up, no significant difference was detected as compared with 1 day postoperatively (P > 0.05). (4) The ratio of good quality of life in 1 month than postoperatively (87%) and in the last folow-up (92%) was significantly greater compared with the preoperative ratio (27%) (P < 0.05). (5) These findings confirmed that curved vertebroplasty device in unilateral pedicle puncture could ensure bilateral symmetric distribution of bone cement. Al patients are satisfied with treatment. It is proved to be a feasible simple and safe method.

Objective: To investigate the relationship between chemosensitivity to L-OHP and expressions of multidrug resistance (MDR) associated factors in lymph node metastases (LNMs) of gastric carcinoma. Methods: The chemosensitivity to L-OHP was measured by MIT assay, and the expressions of P-gp, GST-π, P53, Survivin and Bcl-2 were determined by immunohistochemistry in 54 paired primary tumor (PT) and LNMs of gastric carcinoma. Results: The inhibition rates of LNMs cells for L-OHP were lower than those of PT (P<0.05). The expressions of P-gp, GST-π and Bcl-2 were higher in LNMs than in PT (P<0.05), and no signifi-cant difference was found in the expression of P53 and Survivin between LNMs and PT (P>0.05). Positive cor-relations among P-gp, P53 and Bcl-2 were found in PT and LNMs (r=0.3424, 0.7123, 0.4548, P<0.05). There was no significant difference in the expression of GST-π and Survivin between PT and LNMs (P>0.05). There was statistically negative correlation between inhibition rates and expression of P-gp, GST-π, and Survivin in PT (P<0.05). In LNMs, only Survivin was negatively correlated with inhibition rates of L-OHP (P<0.05). Conclu-sion: The LNMs of gastric carcinoma are heterogeneous with PT in respect to chemosensitivity to L-OHP and expression of multidrug resistance associated factors. The main factors that affect chemosensitivity to L-OHP are also significantly different between PT and LNMs. Effective adjuvant chemotherapy after surgery and re-version to multidrug resistance (MDR) of gastric carcinoma depend on targeting the metastatic lesions of gas-tric carcinoma.

Percutaneous vertebral augmentation is the most commonly used minimally invasive surgery in the treatment of osteoporotic vertebral compression fractures(OVCF).The efficacy and safety have been widely recognized,however,there are still some complications of percutaneous vertebral augmentation.And the most common complication is bone cement leakage,which can lead to nerve root and spinal cord injury,increase the risk of secondary fractures of adjacent vertebral,and even cause serious complications such as pulmonary embolism.The diagnosis,classification,hazard,influence factors and preventive measures of bone cement leakage in vertebral augmentation for OCVF are reviewed in this paper,which will provide reference for prevention and treatment of bone cement leakage in clinical practice.

OBJECTIVETo investigate the possibility of multi-unit ribozymes to purge bone marrow of chronic myelocytic leukemia (CML), its in vitro cleavage ability and the reversal effect on CML cell's malignant phenotype.

METHODSAs bcr-abl fusion gene plays an important role in CML pathology, three single-unit ribozymes were designed and synthesized in 44 base pairs near the fusion point, two enzyme cleavage sites on bcr gene and one on abl gene. Multi-unit ribozymes' in vitro transcription and retroviral vector through gene recombination were constructed. Then, its in vitro cleavage ability was tested and the retroviral vector was transfected into K562 cell. Through MTT assay, the incorporation rate of (3)H-TdR, RT-PCR, Southern and Northern blot hybridization, flow cytometry, transmission and scanning electron microscopy were used to study the effect of multi-unit ribozymes on CML cell proliferation, cell structure, cell cycle and the induction of apoptosis.

RESULTSMulti-unit ribozymes had in vitro cleavage efficiency of 70.8%. After the transfection of multi-unit ribozymes retroviral vector into K562 cell, cell proliferation and DNA synthesis were greatly reduced with an inhibition rate of about 50% after 96 hours of transfection. Multi-unit ribozymes could cleave K562 cell's RNA with a reduction rate about one 1 000 th of the original. By flow cytometry (FCM), 18.4% cells underwent apoptosis after 72 hours transfection with most of the cells blocked in the G phase. Here, the ratio in S phase was lowered by 41.9%. Under transmission and scanning electron microscope, compaction of nuclear chromation and apoptosis bodies were observed in the transfected cells.

CONCLUSIONMulti-unit ribozymes possess high cleavage ability in vitro. The ribozymes, whose retroviral vector being transfected into CML cell, are able to express a lasting ability to cleave the fusion gene, induce apoptosis, reduce cell proliferation, revert the malignant phenotype. It is possible to make use of multi-unit ribozymes to purge CML bone marrow. Therefore, multi-unit ribozymes may very well be valuable in the gene therapy of CML.

Apoptosis ; Cell Division ; drug effects ; Fusion Proteins, bcr-abl ; genetics ; metabolism ; Humans ; K562 Cells ; RNA, Catalytic ; metabolism ; pharmacology