Cytological and Proteomic Analyses of Osmunda cinnamomea Germinating Spores Reveal Characteristics of Fern Spore Germination and Rhizoid Tip Growth.

Fern spore is a good single-cell model for studying the sophisticated molecular networks in asymmetric cell division, differentiation, and polar growth. Osmunda cinnamomea L. var. asiatica is one of the oldest fern species with typical separate-growing trophophyll and sporophyll. The chlorophyllous spores generated from sporophyll can germinate without dormancy. In this study, the spore ultrastructure, antioxidant enzyme activities, as well as protein and gene expression patterns were analyzed in the course of spore germination at five typical stages (i.e. mature spores, rehydrated spores, double-celled spores, germinated spores, and spores with protonemal cells). Proteomic analysis revealed 113 differentially expressed proteins, which were mainly involved in photosynthesis, reserve mobilization, energy supplying, protein synthesis and turnover, reactive oxygen species scavenging, signaling, and cell structure modulation. The presence of multiple proteoforms of 25 differentially expressed proteins implies that post-translational modification may play important roles in spore germination. The dynamic patterns of proteins and their encoding genes exhibited specific characteristics in the processes of cell division and rhizoid tip growth, which include heterotrophic and autotrophic metabolisms, de novo protein synthesis and active protein turnover, reactive oxygen species and hormone (brassinosteroid and ethylene) signaling, and vesicle trafficking and cytoskeleton dynamic. In addition, the function skew of proteins in fern spores highlights the unique and common mechanisms when compared with evolutionarily divergent spermatophyte pollen. These findings provide an improved understanding of the typical single-celled asymmetric division and polar growth during fern spore germination.

Leflunomide in addition to steroids improves proteinuria and renal function in adult Henoch-Schoenlein nephritis with nephrotic proteinuria.

AIM: Henoch-Schoenlein nephritis (HSPN) is a severe disease in adults and may cause renal insufficiency in a large portion of patients. But its rarity has led to lack of data. There are few controlled studies on therapy with immunosuppressants in HSPN adults. This study aims to evaluate the effect of leflunomide on HSPN adults with nephrotic proteinuria. METHODS: We retrospectively studied 65 adult patients who had biopsy-proven HSPN with nephrotic proteinuria. Twenty-seven patients (Group P) only received steroids, and 38 (Group P + L) were treated with leflunomide in addition to steroids. The clinical features, laboratory data and pathological findings of both groups were analyzed. RESULTS: The two groups were well-matched at baseline. After 24 months of treatment, urinary protein excretion of both groups decreased significantly from the baseline, and the estimated glomerular filtration rate (eGFR) was higher in Group P + L. Four patients in Group P and three in Group P + L developed to end-stage renal disease at the most recent follow-up. Group P + L showed better renal outcome than Group P. The treatment group and the degree of mesangial hypercellularity were significantly related to renal prognosis. CONCLUSION: Leflunomide combined with steroids is effective for treating adult HSPN with nephrotic proteinuria.