BACKGROUND: Recently, trans-pedicle screw internal fixation has markedly improved the rigidity of spinal fixation and hence the fusion rate. But when placed incorrectly, the pedicle screw can injure the spinal cord and/or nerve roots, resulting in serious complications.OBJECTIVE: To evaluate the application value of preoperative CT scans-based navigation technique in the spinal pedicle screw internal fixation surgery.DESIGN, TINE AND SETTING: A prospective, randomized, and controlled observation was performed at the Department of Orthopedics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences between January 2006 and December 2008.PARTICIPANTS: A total of 95 patients who underwent pedicle screw internal fixation due to spine diseases were randomly assigned to a navigation group (n = 45) and a conventional group (n = 50).METHODS: In the navigation group, patients were subjected to pedicle screw insertion with the assistance of computer navigation technique and while in the conventional group, patients underwent pedicle screw insertion using the conventional anatomic landmark combined with fluoroscopy.MAIN OUTCOME MEASURES: Screw channel preparation time, excellent and good rate of screw position, and postoperative complications.RESULTS: In the navigation group, totally 206 pedicle screws were inserted under navigation guidance, with an excellent and good rate of 96.1%; and navigation could not be continued in 9 patients for a three-dimensional registration error. In the conventional group, altogether 285 pedicle screws were inserted, and the excellent and good rate was 100%. No significant difference was found between the two groups (P > 0.05). The navigation group exhibited longer screw channel preparation time than the conventional group [(360±22) seconds vs. (56+8) seconds, P < 0.01]. No postoperative complications were found in each group.CONCLUSION: The preoperative CT scans-based navigation technique produces similar accuracy of pedicle screw insertion, but markedly prolonged operation time, compared with the conventional anatomic landmarks, exhibiting limited application value in the spinal pedicle screw internal fixation.

OBJECTIVETo investigate telomerase gene expression in precancerous mammary lesion, such as atypical ductal hyperplasia and breast cancer and to study the relationship between expression and malignant transformation.

METHODSExpression of human telomerase genes (hTR) and human reverse transcriptase gene (hTRT) in 76 cases of mammary tissue was evaluated using in situ hybridization and included 50 cases of mammary hyperplasia, 6 of which were benign hyperplasia, 9 were mild atypical hyperplasia, 12 were moderate atypical hyperplasia, 23 were severe atypical hyperplasia and 26 were mammary cancer.

RESULTSThe expressions of hTR and hTRT mRNA were much weaker or negative in benign hyperplasia (16.6%, 0), weak to mild moderate in atypical hyperplasia (22.2%, 11.1%, 33.3%, 25.0%), strong in severe atypical hyperplasia (60.9%, 52.1%), and significantly strong in mammary cancer (88.5%, 80.8%). The difference between mild-moderate atypical hyperplasia, invasive ductal carcinoma and severe atypical hyperplasia was significant (P < 0.05) and the difference between severe atypical hyperplasia and intraductal carcinoma was not significant (P > 0.05).

CONCLUSIONTelomerase genes (hTR and hTRT) expressions are related to the transformation of atypical hyperplasia. Activated telomerase may play a role in mammary cancer development.

Breast ; metabolism ; pathology ; Breast Neoplasms ; genetics ; pathology ; DNA-Binding Proteins ; Female ; Gene Expression ; Humans ; Precancerous Conditions ; genetics ; pathology ; RNA ; genetics ; physiology ; RNA, Messenger ; analysis ; Telomerase ; genetics ; physiology

OBJECTIVETo investigate the relationship of telomerase genes and the malignant transformation of atypical mammary ductal hyperplasia.

METHODSTelomerase genes hTR and hTRT in 50 cases of mammary hyperplasia (the cases included 6 benign hyperplasia, 9 mild atypical hyperplasia, 12 medium atypical hyperplasia, 23 severe atypical hyperplasia) and 26 cases of breast carcinoma were detected by in situ hybridization.

RESULTSThe expression of hTR and hTRT mRNA were weak or negative in benign hyperplasia (1/6, 0), weaker in mild-moderate atypical hyperplasia (2/9, 1/9, 4/12, and 3/12), strong in severe atypical hyperplasia (14/23, 60.9% and 12/23, 52.1%), while very strong expression (23/26, 88.5% and 21/25, 80.8%) in carcinoma of the breast. The difference between mild-moderate atypical hyperplasia, invasive ductal carcinoma and severe atypical hyperplasia was significant (P < 0.05) and the difference between severe atypital hyperplasia and intraductal carcinoma was not significant (P > 0.05).

CONCLUSIONSTelmerase genes (hTR, hTRT) expression is closely related to the malignant transformation of atypical hyperplasia. The reactivated telomerase may play a crucial role in the development of breast cancer.

Breast Neoplasms ; enzymology ; pathology ; Carcinoma, Intraductal, Noninfiltrating ; enzymology ; pathology ; DNA-Binding Proteins ; Female ; Gene Expression ; Humans ; RNA, Messenger ; Telomerase ; genetics

Increased microglial activation and neuroinflammation within autonomic brain regions such as the rostral ventrolateral medulla (RVLM) have been implicated in stress-induced hypertension (SIH). Prorenin, a member of the brain renin-angiotensin system (RAS), can directly activate microglia. The present study aimed to investigate the effects of prorenin on microglial activation in the RVLM of SIH rats. Rats were subjected to intermittent electric foot-shocks plus noise, this stress was administered for 2 h twice daily for 15 consecutive days, and mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA) were monitored. The results showed that MAP and RSNA were augmented, and this paralleled increased pro-inflammatory phenotype (M1) switching. Prorenin and its receptor (PRR) expression and the NLR family pyrin domain containing 3 (NLRP3) activation were increased in RVLM of SIH rats. In addition, PLX5622 (a microglial depletion agent), MCC950 (a NLRP3 inhibitor), and/or PRO20 (a (Pro)renin receptor antagonist) had antihypertensive effects in the rats. The NLRP3 expression in the RVLM was decreased in SIH rats treated with PLX5622. Mito-tracker staining showed translocation of NLRP3 from mitochondria to the cytoplasm in prorenin-stimulated microglia. Prorenin increased the ROS-triggering M1 phenotype-switching and NLRP3 activation, while MCC950 decreased the M1 polarization. In conclusion, upregulated prorenin in the RVLM may be involved in the pathogenesis of SIH, mediated by activation of the microglia-derived NLRP3 inflammasome. The link between prorenin and NLRP3 in microglia provides insights for the treatment of stress-related hypertension.