基于GIS和CSLE的陕西省土壤侵蚀定量评价方法研究

通过对陕西省土壤侵蚀的定量评估,探索省域尺度上土壤侵蚀定量评价制图方法,以期为第四次全国土壤侵蚀普查提供技术支撑。利用陕西省日降雨数据、土壤类型图、土地利用图、DEM、植被覆盖图,选择CSLE模型,在ArcGIS平台上计算研究区2006年土壤侵蚀量,并与水利部标准评价结果进行对比分析。探索了坡度坡长变换对土壤侵蚀的影响。定量化的评价结果能较好的反映气候、土壤及水保措施对土壤侵蚀的影响,比水利部标准评价结果更能反映实际侵蚀。坡度坡长变换后对土壤侵蚀有明显影响。在GIS支持下,通过土壤侵蚀模型进行定量评价,可高效、客观反映土壤侵蚀情况及其主要影响因子,对区域治理和有关决策有极其重要参考价值。为了准确真实的反映土壤侵蚀程度,必须进行坡度坡长变换。

Preliminary Criteria for Global Flares in Childhood-Onset Systemic Lupus Erythematosus

Objective. To develop widely acceptable preliminary criteria of global flare for childhood-onset systemic lupus erythematosus (cSLE).Methods. Pediatric rheumatologists (n = 138) rated a total of 358 unique patient profiles with information about the cSLE flare descriptors from 2 consecutive visits: patient global assessment of well-being, physician global assessment of disease activity (MD-global), health-related quality of life, anti-double-stranded DNA antibodies, disease activity index scores, protein: creatinine (P:C) ratio, complement levels, and erythrocyte sedimentation rate (ESR). Based on 2,996 rater responses about the course of cSLE (baseline versus followup), the accuracy (sensitivity, specificity, and area under the receiver operating characteristic curve) of candidate flare criteria was assessed. An international consensus conference was held to rank these candidate flare criteria as per the American College of Rheumatology recommendations for the development and validation of criteria sets.Results. The highest-ranked candidate criteria considered absolute changes (Delta) of the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) or British Isles Lupus Assessment Group (BILAG), MD-global, P:C ratio, and ESR; flare scores can be calculated (0.5 x Delta SLEDAI + 0.45 x Delta P:C ratio + 0.5 x Delta MD-global + 0.02 x Delta ESR), where values of >= 1.04 are reflective of a flare. Similarly, BILAG-based flare scores (0.4 x Delta BILAG + Delta 0.65 x Delta P:C ratio + 0.5 + Delta MD-global + 0.02 x Delta ESR) of >= 1.15 were diagnostic of a flare. Flare scores increased with flare severity.Conclusion. Consensus has been reached on preliminary criteria for global flares in cSLE. Further validation studies are needed to confirm the usefulness of the cSLE flare criteria in research and for clinical care.

Pancreatitis subtypes survey in 852 childhood-onset systemic lupus erythematosus patients: a multicenter cohort

Pancreatitis is a rare and a life-threatening SLE manifestation in childhood-onset systemic lupus erythematosus (c-SLE). The objective of this study was to systematically classify pancreatitis in c-SLE according to the International Study Group of Pediatric Pancreatitis (INSPPIRE) and determine the overall prevalence, clinical features, laboratory and first episode outcomes. A multicenter cohort study in 10 Pediatric Rheumatology centers, including 852 cSLE patients. Pancreatitis was diagnosed in 22/852 (2.6%) cSLE patients. It was classified as acute pancreatitis in 20 (91%), acute recurrent pancreatitis in 2 (9%) and none of them had chronic pancreatitis. None of them had gallstones, traumatic pancreatitis or reported alcohol/tobacco use. The comparison of patients with pancreatitis (first episode) and without this complication revealed a shorter disease duration [1(0-10) vs. 4(0-23) years, p < 0.0001] and higher median of SLEDAI-2K [21(0-41) vs. 2(0-45), p < 0.0001]. The frequencies of fever (p < 0.0001), weight loss (p < 0.0001), serositis (p < 0.0001), nephritis (p < 0.0001), arterial hypertension (p < 0.0001), acute renal failure (p < 0.0001), macrophage activation syndrome (p < 0.0001) and death (p = 0.001) were also higher in patients with pancreatitis. The frequencies of intravenous methylprednisolone use (p < 0.0001) and the median of prednisone dose [55(15-60) vs. 11(1-90)mg/day, p < 0.0001] were significantly higher in patients with pancreatitis. Of note, the two patients with acute recurrent pancreatitis had two episodes, with pain-free interval of 1 and 4 years. This was the first study characterizing pancreatitis using the INSPPIRE standardized definitions in patients with cSLE showing that the predominant form is acute pancreatitis seen in association with glucocorticoid treatment and active severe disease.

Inactive Disease and Remission in Childhood-Onset Systemic Lupus Erythematosus

Objective. To define inactive disease (ID) and clinical remission (CR) and to delineate variables that can be used to measure ID/CR in childhood-onset systemic lupus erythematosus (cSLE). Methods. Delphi questionnaires were sent to an international group of pediatric rheumatologists. Respondents provided information about variables to be used in future algorithms to measure ID/CR. The usefulness of these variables was assessed in 35 children with ID and 31 children with minimally active lupus (MAL). Results. While ID reflects cSLE status at a specific point in time, CR requires the presence of ID for >6 months and considers treatment. There was consensus that patients in ID/CR can have <2 mild nonlimiting symptoms (i.e., fatigue, arthralgia, headaches, or myalgia) but not Raynaud's phenomenon, chest pain, or objective physical signs of cSLE; antinuclear antibody positivity and erythrocyte sedimentation rate elevation can be present. Complete blood count, renal function testing, and complement C3 all must be within the normal range. Based on consensus, only damage-related laboratory or clinical findings of cSLE are permissible with ID. The above parameters were suitable to differentiate children with ID/CR from those with MAL (area under the receiver operating characteristic curve >0.85). Disease activity scores with or without the physician global assessment of disease activity and patient symptoms were well suited to differentiate children with ID from those with MAL. Conclusion. Consensus has been reached on common definitions of ID/CR with cSLE and relevant patient characteristics with ID/CR. Further studies must assess the usefulness of the data-driven candidate criteria for ID in cSLE.