Patients with early-onset primary Sjögren's syndrome have distinctive clinical manifestations and circulating lymphocyte profiles.

OBJECTIVES: To further investigate the clinical characteristics and circulating lymphocyte profiles of patients with early-onset primary Sjögren's syndrome (pSS). METHOD: Data of 333 patients with pSS were analysed retrospectively. Early onset was defined as a pSS diagnosis at an age of 35 years or younger. The clinical, laboratory and immunophenotypic profiles of peripheral blood lymphocyte subsets were compared between early- and later-onset pSS. RESULTS: Thirty-six (10.81%) patients matched the definition of early-onset pSS, with age at disease onset being 28.97 (5.53) years. Elevated serum IgG level (77.14% vs 31.16%, P <0.001), low C3 (41.67% vs 20.20%, P =0.004) and C4 levels (27.78% vs 6.40%, P <0.001), anti-SSA positivity (91.67% vs 51.85%, P <0.001) and anti-SSB positivity (50% vs 20.54%, P <0.001) were more frequent in early-onset patients. The frequencies of hematological (80.56% vs 52.53%, P =0.001), renal (19.44% vs 5.05%, P =0.005) and mucocutaneous involvement (50% vs 22.56%, P <0.001) were significantly higher in the early-onset pSS group, which showed a higher 2010 EULAR SS Disease Activity Index (ESSDAI) [11(6.25-17) vs 7(3-12); P =0.003], compared with the later-onset group. In addition, profound CD4+ T-cell lymphopenia was found in patients with early-onset. CONCLUSIONS: Patients with early-onset pSS have distinctive clinical manifestations and greater activation of the cellular immune system, present with more severe clinical symptoms and immunological features, have increased activation of circulating T cells and have an unfavourable prognosis. Thus, they require more positive treatment with glucocorticoids and/or immunosuppressants and merit closer follow-up and regular monitoring.

Spatio-temporal variations and coupling of human activity intensity and ecosystem services based on the four-quadrant model on the Qinghai-Tibet Plateau.

Human activities have an impact on the structure and function of ecosystems, which in turn affects ecosystem service (ES) supply and demand. Based on the four-quadrant model of human activities and ecosystem services, this study evaluated the ecological quality at the county scale on the Qinghai-Tibet Plateau (QTP). Results showed: (1) Human activity intensity (HAI) showed great spatio-temporal variations across the QTP. The mean HAI was low overall and increased by 4% during 2000-2015. HAI in more than 13% of the area of the QTP showed an increasing trend and high HAI levels were mainly distributed in the eastern and central parts. A low HAI level occupied the majority of the study area and declined during the period. (2) The mean ES balance declined during the period and exhibited great spatial variations, with the higher ES balance mainly distributed in the mid-eastern cities of the QTP. The ES balance in approximately 68% of the cities decreased, indicating the ESs were in degradation, with demand exceeding supply. (3) Approximately 98% of the study area, including 205 counties, was in the first, second and fourth quadrant, and only 2% was in the third quadrant, indicating that ecological quality became better overall on the QTP. During 2000-2015, 87.14% of counties were nearly unchangeable-these were distributed in the most regions of the QTP, and only 9.79% and 3.08% of counties were improving and degrading, respectively, mainly distributed in the mid-eastern regions. The change implied that the ecosystems were basically in a stable state and the environment greatly improved on the QTP from 2000 to 2015. This study contributes to exploring the effect of human activity on ecosystem service, thereby providing credible guidance for regional ecosystem management.