Long-Term Prognostic Factors in Patients With Antineutrophil Cytoplasmic Antibody-Associated Vasculitis: A 15-Year Multicenter Retrospective Study.

Background: Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a multisystem autoimmune disease with small-vessel involvement. In AAV, microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA) are major clinicopathologic variants. In addition, myeloperoxidase (MPO) and proteinase 3 (PR3) are major target antigens. The objective of the study was to explore the predictive factors for long-term survival in AAV patients. Materials and Methods: A multicenter retrospective study was carried out on 407 patients between 2005 and 2020. Clinical parameters were obtained from laboratory tests including the ANCA types, antinuclear antibody (ANA), extractable nuclear antigen (ENA), anti-streptolysin O (ASO), glomerular filtration rate (GFR), and the laboratory examinations for the blood routine, liver function, renal function, and immunity, etc. The data for clinical parameters were collected from electronic medical records (EMRs), and the data for patient survival were acquired through regular follow-up. The association of clinical parameters with overall survival (OS) along with 3-year and 5-year survival rates was analyzed, and the nomogram as a predictive model was established according to the analysis results. Results: In the present study, 336 (82.6%) patients and 46 (11.3%) patients were diagnosed with MPA and GPA, respectively. The mean and median OS for all the patients were 2,285 and 2,290 days, respectively. The 1-year, 3-year, 5-year, and 10-year cumulative survival rates for all the patients were 84.2%, 76.3%, 57.2%, and 32.4%, respectively. Univariate and multivariate survival analyses indicated that the independent prognostic factors included age, pathological categories (MPA, GPA, and other types), serum ANCA types (negative or positive for MPO and/or PR3), ANA, ASO, GFR, lymphocyte, neutrophil-to-lymphocyte ratio (NLR), and C-reactive protein (CRP), and these clinical parameters except for ASO were used to construct a nomogram. The nomogram for 3-year and 5-year survival rates had a C-index of 0.721 (95% CI 0.676-0.766). The calibration curves showed that the predicted values of the nomogram for 3-year and 5-year survival rates were generally consistent with practical observed values, and decision curve analysis (DCA) further demonstrated the practicability and accuracy of the predictive model. Conclusion: Laboratory tests at diagnosis have great significance in the prediction of long-term survival in AAV patients.

[Radial variation and time lag of sap flow of Populus gansuensis in Minqin Oasis, Northwest].

Sap flow of tree trunk is very important to reflect the dynamics of physiological activities, as well as to estimate the water consumption of individual plant. In the present study, we used the thermal dissipation technique to monitor the sap flow velocity (J) at four depth loci (i. e. 2 cm, 3 cm, 5 cm, 8 cm) of three Populus gansuensis trees (30 year-old) in Minqin Oasis for two consecutive growing seasons. The results showed that there were significant differences among J values at four depth loci under tree trunk cambium. J value at the 3 cm depth locus (J3) of the tree trunk was the highest, and then in sequences, were 2 cm, 5 cm and 8 cm depth loci (J2, J5 and J8). J value (J3) on typical sunny days in June with the highest atmospheric potential evapotranspiration (ET0) was up to 28.53 g · cm(-2) · h(-1), which was 1.42, 2.74 and 4.4 times of J2, J5 and J8, respectively. In the process of diurnal variation of sap flow velocity, the peak value time of J at the four depth loci of the tree trunk was different, but the differences among them were within 20 min. Furthermore, the peak value time of sap flow velocity was very different to that of solar radiation (Rs) and air vapour pressure deficit (VPD). The time lag between J and Rs was from 55 to 88 min on typical sunny days during the main growing seasons (from June to August), and, positively related to the depth of the locus under tree trunk cambium, while the time lag between J and VPD reached 60-96 min, and was negatively related to the depth of the locus. The seasonal variation patterns of J were consistent with ET0. With the increase of tree physiological activities, there was a trend that the major water transportation layer extended to the interior sapwood. The most important meteorological factor was the solar radiation, which primarily drove sap flow at different depths of tree trunk. However, the secondary factor changed along with the depth, and VPD became increasingly important with increasing the depth.