Prediction Model for Lumbar Curve Correction after Selective Thoracic Fusion in Lenke 1 and 2 Adolescent Idiopathic Scoliosis.

STUDY DESIGN: A retrospective study. OBJECTIVE: To identify independent risk factors and construct a prediction model for lumbar curve correction (LCC) after selective thoracic fusion (STF) in patients with Lenke 1 and 2 adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: STF has been widely applied in Lenke 1 and 2 AIS patients. However, LCC after STF is still controversial. METHODS: 128 patients undergoing STF with at least 2 years follow-up were included. Cases were divided into high-LCC group and low-LCC group according to a rounded-up median of 65%. 49 variables were taken into account. Logistic regression was applied to identify independent predictive factors. Prediction model was established by backward stepwise regression, and its evaluation was implemented on R. RESULTS: Five parameters showed independent predictive value for low LCC: Right shoulder higher before surgery [right shoulder higher vs. balanced: odds ratio (OR)=0.244, P=0.014], postoperative Cobb angle of lumbar curve (LC) (OR=1.415, P=0.001, cut-off value=11°), lowest instrumented vertebra (LIV) distal to end vertebra (no vs. yes: OR=4.587, P=0.013), postoperative LIV tilt (OR=0.686, P=0.010, cut-off value=6.85°) and postoperative LIV+1 tilt (OR=1.522, P=0.005, cut-off value=6.25°). The prediction model included six variables: lumbar modifier, preoperative shoulder balance, postoperative Cobb angle of LC, LIV position, postoperative LIV tilt and postoperative LIV+1 tilt. Model evaluation demonstrated satisfactory capability and stability [area under curve=0.890, 10-fold cross-validation accuracy=0.782]. CONCLUSION: Preoperative shoulder balance, Cobb angle of LC, LIV position, postoperative LIV and LIV+1 tilt could be used to prognosticate LCC after STF. A model with solid prediction ability was established, which could further our understanding of LCC and assist in making clinical decisions.

Real-Time Simulation of Open Quantum Spin Chains with the Inchworm Method.

We study the real-time simulation of open quantum systems, where the system is modeled by a spin chain with each spin associated with its own harmonic bath. Our method couples the inchworm method for the spin-boson model and the modular path integral methodology for spin systems. In particular, the introduction of the inchworm method can significantly suppress the numerical sign problem. Both methods are tweaked to make them work seamlessly with each other. We represent our approach in the language of diagrammatic methods and analyze the asymptotic behavior of the computational cost. Extensive numerical experiments are performed to validate our method.

Blocking circadian clock factor Rev-erbα inhibits growth plate chondrogenesis via up-regulating MAPK-ERK1/2 pathway.

Emerging evidence indicated circadian clock gene Rev-erbα was involved in cartilage metabolism, however the contribution of Rev-erbα to growth plate chondrogenesis remains unknown. Here, we found that Rev-erbα exhibited the spatiotemporal expression model in growth plate. Moreover, Rev-erbα antagonist SR8278 inhibited longitudinal elongation of metatarsal bone ex vivo. And morphological analysis exhibited SR8278 led to the reduced height of growth plate and hypertrophic zone. Furthermore, blocking Rev-erbα suppressed the proliferation and hypertrophic differentiation of chondrocytes in growth plate. Similarly, knock-down Rev-erbα inhibited the proliferation and differentiation of primary chondrocytes in vitro. The mechanistic study indicated that knock-down Rev-erbα up-regulated MAPK-ERK1/2 pathway in chondrocytes. However, restraint of MAPK-ERK1/2 pathway alleviated partially SR8278-inhibited longitudinal elongation of metatarsal bone and growth plate development. Therefore, our results provide evidence of the vital role of Rev-erbα on growth plate chondrogenesis.