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Porous beta-tricalcium phosphate (TCP) has been known to have osteoinductive potential in ectopic site implantation in canine models without the use of osteoinductive substances or cell transplantation. Prostaglandin E2 receptors, particularly EP4, are known to play an important role in osteogenesis. EP4 agonists have been demonstrated to have positive effects on bone remodeling and bone morphogenic protein-induced ectopic bone formation in rodent models. We examined the efficiency of porousbeta-TCP-induced osteoinduction in beagles by the graded-release EP4 agonist, which was injected at their buttocks intramuscularly. Newly formed bone was observed on and after 3 weeks in the EP4 agonist-injected, while on and after 6 weeks in control groups, respectively. After that the bone resorption and the beta-TCP degradation was accelerated in EP4 agonist-injected group. Tartarate-resistant acid phosphatase-positive cells appeared in each group before bone formation, and the number of these cells reduced gradually; however, more multinucleated and larger cells appeared, particularly in the injected group. Injection of an EP4 agonist was proved to accelerate the osteoinduction and degradation of beta-TCP in canine model. Histological analysis revealed that the EP4 agonist stimulated osteoclastogenesis before bone formation.  相似文献   
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International Journal of Clinical Pharmacy - The profile of ceftriaxone-induced encephalopathy is not well understood. To identify risk factors associated with ceftriaxone-induced encephalopathy....  相似文献   
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Background Context

Adult spinal deformity correction sometimes involves long posterior pedicle screw constructs extending from the lumbosacral spine to the thoracic vertebra. As fusion obliterates motion and places supraphysiological stress on adjacent spinal segments, it is crucial to ascertain the ideal upper instrumented vertebra (UIV) to minimize risk of proximal junctional failure (PJF). The T10 vertebra is often chosen to allow bridging of the thoracolumbar junction into the immobile thoracic vertebrae on the basis that it is the lowest immobile thoracic vertebra strut by the rib cage.

Purpose

This study aimed to characterize the range of motion (ROM) of each vertebral segment from T7 to S1 to determine if T10 is truly the lowest immobile thoracic vertebra.

Study Design/Setting

This is a prospective, comparative study.

Patient Sample

Seventy-nine adults (mean age of 45.4 years) presenting with low back pain or lower limb radiculopathy or both, without previous spinal intervention, metastases, fractures, infection, or congenital deformities of the spine, were included in the study.

Outcome Measures

A ROM >5° across two vertebral segments as determined by the Cobb method from radiographs.

Methods

Lumbar flexion-extension and neutral erect radiographs were obtained in randomized order using a slot scanner. Segmental ROM was measured from T7–T8 to L5–S1 and analyzed for significant differences using t tests. Age, gender, radiographical indices such as standard spinopelvic parameters, sagittal vertical axis (SVA), C7–T12 SVA, T1 slope, thoracic kyphosis (TK), and lumbar lordosis (LL) were studied via multivariate analysis to identify predictive factors for >5° change in ROM at the various segmental levels. There were no sources of funding and no conflicts of interest associated with this study.

Results

In the thoracolumbar spine, significant decreases in ROM when compared with the adjacent caudad segment occurs up to T9–T10, with mean total ROM of 1.98±1.47° (p<.001) seen in T9–T10, 2.19±1.67° (p<.001) in T10–T11, and 3.92±3.21°(p<.001) in T11–T12. The total ROM of T8–T9 (2.53±1.79°) was not significantly different from that of T9–T10 (p=.261). At the thoracolumbar junction, absence of scoliosis (OR 11.37, p=.020), high pelvic incidence (OR 1.14, p=.046), and low T1 slope (OR 1.45, p=.030) were predictive of ROM >5°.

Conclusions

Lumbar spine flexion-extension ROM decreases as it approaches the thoracolumbar junction. T10 is indeed the lowest immobile thoracic vertebra strut by the rib cage, and the last significant decrease in ROM is observed at T9–T10, in relation to T10–T11. However, because this also implies that a UIV of T10 would mean there is only one level of fixation above the relatively mobile segment, while respecting other factors that influence UIV selection, we propose the T9 vertebra as a more ideal UIV to fulfill the biomechanical concept of bridge fixation. However, this decision should still be taken on a case-by-case basis.  相似文献   
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AIM:To evaluate weight loss and surgical outcomes of Roux-en-Y gastric bypass(RYGB)and laparoscopic adjustable gastric band(LAGB).METHODS:Data relating to changes in body mass index(BMI)and procedural complications after RYGB(1995-2009;n=609;116M:493F;42.4±0.4 years)or LAGB(2004-2009;n=686;131M:555F;37.2±0.4years)were extracted from prospective databases.RESULTS:Pre-operative BMI was higher in RYGB than LAGB patients(46.8±7.1 kg/m2vs 40.4±4.2 kg/m2,P<001);more patients with BMI<35 kg/m2underwent LAGB than RYGB(17.1%vs 4.1%,P<0.0001).BMI decrease was greater after RYGB.There were direct relationships between weight loss and pre-operative BMI(P<0.001).Although there was no difference in weight loss between genders during the first 3-year post-surgery,male LAGB patients had greater BMI reduction than females(-8.2±4.3 kg/m2vs-3.9±1.9kg/m2,P=0.02).Peri-operative complications occurred more frequently following RYGB than LAGB(8.0%vs0.5%,P<0.001);majority related to wound infection.LAGB had more long-term complications requiring corrective procedures than RYGB(8.9%vs 2.1%,P<0.001).Conversion to RYGB resulted in greater BMI reduction(-9.5±3.8 kg/m2)compared to removal and replacement of the band(-6.0±3.0 kg/m2).Twelve months post-surgery,fasting glucose,total cholesterol and low density lipoprotein levels were significantly lower with the magnitude of reduction greater in RYGB patients.CONCLUSION:RYGB produces substantially greater weight loss than LAGB.Whilst peri-operative complications are greater after RYGB,long-term complication rate is higher following LAGB.  相似文献   
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