[The consistency of skeletal muscle mass measured by CT at L1 and L3 levels and the correlation of skeletal muscle density at L1 level with prognosis in dialysis patients].

Objective: To investigate the consistency of skeletal muscle mass by CT at 1st lumbar vertebrae (L1) and 3rd lumbar vertebrae (L3) levels and the correlation of skeletal muscle density (SMD) at L1 level with prognosis in dialysis patients. Methods: A total of 1 020 patients who underwent initial dialysis and had CT examination data in four centers (Zhongda Hospital Affiliated to Southeast University, the Third Affiliated Hospital of Soochow University, Taizhou People's Hospital Affiliated to Nanjing Medical University and the Affiliated Hospital of Yangzhou University) from January 2014 to December 2019 were retrospectively collected. The skeletal muscle index (SMI) and SMD at L1 and L3 CT images were measured and calculated in patients with both L1 and L3 level CT images. The consistency of SMI and SMD at L1 and L3 levels was analyzed, and the cut-off value of SMI and SMD at L1 level for predicting all-cause mortality and their correlation with the prognosis of dialysis patients were studied. Cox regression model was used to analyze the risk factors for all-cause death and cardiac death. Results: A total of 383 patients had both L1 and L3 level images, including 233 males and 150 females. The average SMD value of 16 samples (4.2%) exceeded the 95% consistency limit range (-8.71 to 7.75 HU), and the average SMI value of 15 samples (3.9%) exceeded the 95% consistency limit range (-20.45 to 9.53 HU). The optimal cut-off value of SMD at L1 level for predicting all-cause mortality was 36.46 HU and the area under curve (AUC) of receiver operating characteristic (ROC) curve was 0.658 (95%CI: 0.596-0.721, P<0.001), with the sensitivity and specificity of 83.8% and 57.5%, respectively. SMI at L1 level was not significantly associated with all-cause mortality (P=0.299). Multivariate Cox regression analysis showed that low SMD at L1 level was associated with all-cause mortality (HR=2.861, 95%CI: 1.576-5.193, P=0.001) and cardiac death (HR=3.771, 95%CI:1.462-9.724, P=0.006). Conclusions: SMD at L1 levelis consistent with SMD at L3 level and can be used to evaluate muscle mass. Low SMD is a risk factor for mortality in dialysis patients.

Association of interleukin-6 and CD4+ T cells and two-week prognosis of patients with COVID-19: a predictive role.

OBJECTIVE: The aim of this study was to determine the association of inflammation and immune responses with the outcomes of patients at various stages, and to develop risk stratification for improving clinical practice and reducing mortality. PATIENTS AND METHODS: We included 77 patients with primary outcomes of either death or survival. Demographics, clinical features, comorbidities, and laboratory tests were compared. Linear, logistic, and Cox regression analyses were performed to determine prognostic factors. RESULTS: The average age was 59 years (35-87 years). There were 12 moderate cases (16.2%), 42 severe cases (54.5%), and 23 critical cases (29.9%); and 41 were male (53.2%). Until March 20, 68 cases were discharged (88.3%), and nine critically ill males (11.7%) died. Interleukin-6 (IL-6) levels on the 1st day were compared with IL-6 values on the 14th day in the severe and the critically ill surviving patients (F=4.90, p=0.034, ß=0.35, 95% CI: 0.00-0.10), and predicted death in the critically ill patients (p=0.028, ß=0.05, OR: 1.05, 95% CI: 1.01-1.10). CD4+ T-cell counts at admission decreased the hazard ratio of death (p=0.039, ß=-0.01, hazard ratio=0.99, 95% CI: 0.98-1.00, and median survival time 13.5 days). CONCLUSIONS: The present study demonstrated that IL-6 levels and CD4+ T-cell count at admission played key roles of predictors in the prognosis, especially for critically ill patients. High levels of IL-6 and impaired CD4+t cells are seen in severe and critically ill patients with COVID-19.

Temperature effect of the local structure in liquid Sb studied with x-ray absorption spectroscopy.

The temperature dependence of the local structure of liquid Sb has been studied by x-ray absorption spectroscopy. It is shown that about 10% of the atoms with coordination of 3 and weak Peierls distortion exist in liquid Sb just above its melting point. The Peierls distortion weakens gradually with increasing temperature and vanishes at about 750 degrees C. This structural variation in liquid Sb is different from the normal liquid-liquid phase transition. This work reveals the relationship between the variation in the local structure and the change in the physical properties, such as the electrical resisitvity of liquid Sb, with temperature. The complete agreement between the measured electrical resistivity values during heating and cooling processes suggests that the structural units with the features of a rhombohedron appear above the melting point of Sb during solidification.