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BACKGROUND CONTEXT
Cervical laminectomy and fusion (CLF) is a common surgical option for multilevel cord compression. Postoperative C5 palsy occurrence after CLF has been a vexing problem for spine physicians. The posterior shift of the cord following laminectomy has been implicated as a major factor for postoperative C5 palsy, but attempts by spine surgeons to mitigate excessive shift while providing sufficient decompression have not been well reported.PURPOSE
To compare the incidence of postoperative C5 palsy after performing selective blocking laminoplasty concurrently with CLF to those of conventional CLF.STUDY DESIGN
A retrospective comparative study of prospectively collected data.PATIENT SAMPLE
Of 116 cervical myelopathy patients with degenerative cervical myelopathy, ossification of the posterior longitudinal ligament, and multilevel disc herniation, 93 patients (69 in group A [CLF group] and 24 in group B [selective blocking laminoplasty with CLF, CLF-S group]) were included in the study.OUTCOME MEASURES
The primary outcome measure was the occurrence of postoperative C5 palsy. Secondary end points included (1) clinical outcomes based on pain intensity, neck disability index (NDI), Japanese Orthopaedic Association (JOA) score, (2) radiologic outcomes including cervical alignment and fusion rate at 1 year and hardware complications, and (3) perioperative data (hospital stay, blood loss, and operative times).METHODS
We compared the occurrence of postoperative C5 palsy, as well as clinical, radiologic, and surgical outcomes, between the two groups at 1-year follow-up.RESULTS
The patients in both groups were statistically similar between the groups with respect to demographic characteristics such as age, sex, smoking status, body mass index, preoperative pathology, surgical segments, and the degree of the cervical lordosis. Postoperative C5 palsy developed in 9 of 61 patients (14%) in group A and in 0 of 24 patients (0%) in group B (CLF-S group) (p=.03). Postoperative neck pain, NDI, and JOA improvement were not significantly different between the two groups (p=.93, 0.90, and 0.79, respectively). Perioperative data did not differ significantly between the two groups.CONCLUSIONS
This study showed that performing selective blocking laminoplasty might lead to reducing the incidence of postoperative C5 palsy in CLF surgery. 相似文献Methods: Fifty-four patients with ACI and 51 healthy controls were included in our study. Baseline characteristics and blood samples were collected for further analysis. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure the serum miR-124 levels. The dual-luciferase reporter assay was used to evaluate the effect of miR-124 on iASPP, a protein that inhibits apoptosis stimulating proteins in the p53 family.
Results: Compared with normal controls, the miR-124 levels in the ACI group rapidly decreased at phase 1 (within 24?h after ischemia) (p?<?0.001) and then gradually increased at phase 2 (48?~?72?h after ischemia) (p?<?0.001) and phase 3 (the 7th day after ischemia) (p?<?0.001). The dual-luciferase reporter assay showed that miR-124 down-regulates iASPP expression in 293T cells.
Conclusion: The miR-124 levels are down-regulated in ACI patients. The dynamic changes of miR-124 might provide a possible method for the detection of ischemic stroke.
- Highlights
The difference in miR-124 expression levels between ACI patients and normal controls.
Dynamic changes of miR-124 expression levels in ACI patients.
The down-regulation of miR-124 upon iASPP expression.
This was the first study to construct a physiologically-based pharmacokinetic (PBPK) model for mirabegron which incorporates the overall elimination pathways of metabolism by cytochrome P450 (CYP) 3A4, uridine 5'-diphosphate-glucuronosyltransferase (UGT) 2B7, and butyrylcholinesterase (BChE) and renal excretion. The objective was to assess the risk of drug-drug interactions (DDIs) by estimating the contribution of each elimination pathway and simulating the magnitude of the DDIs with UGT2B7 inhibitors.
A PBPK model for mirabegron was constructed to reproduce the plasma concentration-time curves from a phase 1 study and the magnitude of the DDI with ketoconazole taking into account the overall elimination pathways. The PBPK model was subsequently verified using data from other DDI studies.
The constructed PBPK model estimated the contribution for each elimination pathway: 44% and 29% for CYP3A4 and UGT2B7 in the liver, 1.6% for UGT2B7 in the kidney, 3.2% for BChE in plasma, and 22% for renal excretion.
Co-administration of probenecid (an UGT2B7 inhibitor) or fluconazole (an UGT2B7 and CYP3A4 inhibitor) was predicted to increase area under the curve for mirabegron to 115% or 174%, respectively.
In conclusion, PBPK modeling and simulation revealed a low DDI risk for mirabegron following co-administration with BChE or UGT2B7 inhibitors.