The clinical characteristics and treatment of "sandwich" atlantoaxial dislocation / 中华骨科杂志

Objective:To evaluate the specialty of the clinical features, treatment procedure, clinical outcome, and prognosis in the patients with "sandwich" atlantoaxial dislocation (AAD).Methods:From 2008 to 2018, 160 cases with "sandwich" AAD were retrospectively selected from the case series of AAD in Peking University Third Hospital. The case series had 80 males and 80 females. The mean age at the initial visit was 35.5±14.6 years (range, 5-77). The clinical courses, treatment methodology and prognosis were reviewed. And the surgical approach, posterior fixation segment and the recovery of neurological function were mainly summarized. The atlantodental interval (ADI), the distance by which the odontoid exceeded the Chamberlain line and the cervical-medullary angle were analyzed.Results:The most common symptoms included weakness or numbness of the limbs (67.5%, 108/160), unstable gait (30%, 48/160) and vertigo (20%, 32/160). Among all, 130 cases (81.3%, 130/160) had myelopathy, with the Japanese Orthopaedic Association (JOA) scores from 4 to 16 (mean JOA scores 13.5±2.5). Cranial neuropathy was involved in 20 cases (12.5%). Radiological findings showed brainstem and/or cervical-medullar in 130 cases (81.3%), syringomyelia in 37 cases (23.1%) and Chiari malformation in 30 cases (18.8%). Computed tomography angiography (CTA) was performed in 90 cases, which showed vertebral artery anomalies in 55 cases (61.0%) and excessive medialized internal carotid artery in 5 cases (5.6%). All cases had no spinal cord or vertebral artery injury. The surgery included posterior occipito-cervical fusion (reducible dislocation, 145 cases), and transoral release followed by posterior fusion (irreducible dislocation, 15 cases). Fifty-seven cases were treated using alternative fixation technique. The average follow-up time was 50.5±22.4 months (range, 24 to 120 months). All of 152 cases (95.0%) achieved solid atlantoaxial fusion; there was no obvious osseous fusion formation on postoperative images in 6 cases (3.8%), but no atlantoaxial instability was found on dynamic radiographs; screw loosening happened in 2 patients (1.2%). Nine patients (5.6%) suffered complications, including 4 cases with recurrent dislocation, 2 screw loosening, 2 cases with bulbar paralysis and 1 wound infection. The mean postoperative JOA was 15.1±1.8 (range, 5-17), and the mean neurological improvement rate was 42.9%±33.3% in the patients with myelopathy.Conclusion:"Sandwich" AAD, a subgroup of AAD, has unique clinical features: earlier onset age and more severe myelopathy. The incidence of bone and vascular malformation is higher. So alternative surgical plan and hybrid fixation should be prepared for this subgroup of AAD.

Current trends in drug metabolism and pharmacokinetics

Pharmacokinetics (PK) is the study of the absorption, distribution, metabolism, and excretion (ADME) processes of a drug. Understanding PK properties is essential for drug development and precision medication. In this review we provided an overview of recent research on PK with focus on the following aspects: (1) an update on drug-metabolizing enzymes and transporters in the determination of PK, as well as advances in xenobiotic receptors and noncoding RNAs (ncRNAs) in the modulation of PK, providing new understanding of the transcriptional and posttranscriptional regulatory mechanisms that result in inter-individual variations in pharmacotherapy; (2) current status and trends in assessing drug-drug interactions, especially interactions between drugs and herbs, between drugs and therapeutic biologics, and microbiota-mediated interactions; (3) advances in understanding the effects of diseases on PK, particularly changes in metabolizing enzymes and transporters with disease progression; (4) trends in mathematical modeling including physiologically-based PK modeling and novel animal models such as CRISPR/Cas9-based animal models for DMPK studies; (5) emerging non-classical xenobiotic metabolic pathways and the involvement of novel metabolic enzymes, especially non-P450s. Existing challenges and perspectives on future directions are discussed, and may stimulate the development of new research models, technologies, and strategies towards the development of better drugs and improved clinical practice.

Valproic acid suppresses SIRT1 inducing hepatotoxicity / 中国药理学通报

Aim To detect the role of sirtuin1 ( SIRT1 ) in hepatotoxity caused by valproic acid ( VPA) . Methods The changes of SIRT1 expression of HepG2 cells were detected by Western blot. And then SIRT1 plasmid or siRNA was transfected to con-struct SIRT1 overexpressed or knocked-down HepG2 cells. Furthermore, SRB assays were taken to observe the changes of viability of these cells exposed to VPA. Results VPA suppressed SIRT1 expression in a time and dose-dependent manner. SIRT1 overexpression showed a protective effect to the cytotoxicity caused by VPA, and the IC50 before and after transfection was (4. 025 ± 0. 47) and (10. 87 ± 1. 50) mmol·L-1 re-spectively. Moreover, transfection of SIRT1 siRNA sensitized HepG2 cells to VPA, and the IC50 before and after transfection was (1. 938 ± 0. 16) and (0. 663 ± 0. 05) mmol·L-1 respectively. Conclusion VPA suppressed SIRT1 expression in HepG2 cells and over-expression of SIRT1 could reduce cytotoxicity induced by VPA.

Comparative Study on Concentration Monitoring of CsA in Human Whole Blood by EMIT and HPLC / 中国药师

Objective:To compare the difference and correlation of HPLC and enzyme-multiplied immunoassay test( EMIT) for the determination of CsA in human whole blood. Methods:A total of 119 clinical samples at different concentrations of CsA were collected and respectively determined by HPLC and EMIT. The difference and correlation of the two determination methods were investigated. Results:There was significant difference in the blood concentrations of CsA determined by HPLC and EMIT(P<0. 05). CsA concen-tration determined by EMIT was 26. 2 ng·ml-1 higher than that determined by HPLC, and 95% CI was (14. 6-37. 7) ng·ml-1 . A satisfactory correlation was achieved between the two methods(r=0. 997 4). Conclusion:There is statistically significant difference in the CsA concentration in whole blood respectively determined by EMIT and HPLC. Attention should be paid to CsA monitoring by E-MIT and HPLC, and relevant adjustment should be carried out.