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Henry Munkholm posted an update 3 days, 6 hours ago
The results demonstrated that certain cellular features contributed to decreased oxygen diffusion among the organs, specifically, those found in the leaf-rhizome and root-rhizome interfaces as well as the suberin and lignin layers in these regions. Additionally, our experiments with a catalase activator and inhibitor validated that a significant amount of the oxygen released in radial oxygen loss could not, in fact, be exclusively supplied by the atmosphere. Thus, a complementary model is proposed in which catalase activity is an important component of radial oxygen loss.Salt stress adversely affects plants by causing osmotic and ionic imbalance. Cellular osmotic adjustment occurs by modulation of water fluxes. Polyamines (PAs) are often advocated to be involved in osmoregulation during stressful conditions, and thus, they serve as potential “osmolytes.” Aquaporins (AQPs), the water-transporting channels, are expected to play crucial roles in osmoregulation. Present investigations on etiolated sunflower seedlings demonstrate a possible correlation between PA homeostasis and maintenance of water balance, as a function of modulation of the abundance of two major AQP subfamilies PIP2 (plasma membrane intrinsic protein 2) and TIP1 (tonoplast intrinsic protein 1). Salt stress (120 mM NaCl) restricts growth of sunflower seedlings and induces reduction in relative water content (RWC). This accompanies enhanced abundance of PIP2s and TIP1s in seedling roots and that of TIP1s in cotyledons, as revealed by Western blot analysis of AQP isoforms and also their imaging by confocal laser scanning microscopy (CLSM). Raising seedlings in the presence of 500 μM of DFMA (DL-α-difluoromethylarginine) or DFMO (DL-α-difluoromethylornithine), which are potent inhibitors of PA biosynthesis enzymes (arginine decarboxylase (ADC) and ornithine decarboxylase (ODC), respectively), significantly promotes root extension, irrespective of NaCl stress, and results in further lowering of salt-induced reduction in RWC in roots and cotyledons. This correlates with enhanced accumulation of both PIP2s and TIP1s in seedling roots, but not in cotyledons. Present work, therefore, implicates PA homeostasis in the maintenance of water status of sunflower seedlings, possibly via regulation of abundance and distribution of AQP isoforms associated with the plasma membrane and tonoplast.Collagen (Col) from marine organisms has been emerging as an important alternative for commercial Col and it has been considered highly attractive by the industry. Despite the positive effects of Col from marine origin, there is still limited understanding of the effects of this natural biomaterial in the process of wound healing in animal studies. In this context, the purpose of this study was to perform a systematic review of the literature to examine the effects of Col from different marine species in the process of skin tissue healing using experimental models of skin wound. The search was carried out according to the orientations of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA), and the descriptors of the Medical Subject Headings (MeSH) were defined “marine collagen,” “spongin,” “spongin,” “skin,” and “wound.” A total of 42 articles were retrieved from the databases PubMed and Scopus. After the eligibility analyses, this review covers the different marine sources of Col reported in 10 different papers from the beginning of 2011 through the middle of 2019. The results were based mainly on histological analysis and it demonstrated that Col-based treatment resulted in a higher deposition of granulation tissue, stimulation of re-epitalization and neoangiogenesis and increased amount of Col of the wound, culminating in a more mature morphological aspect. In conclusion, this review demonstrates that marine Col from different species presented positive effects on the process of wound skin healing in experimental models used, demonstrating the huge potential of this biomaterial for tissue engineering proposals.Dengue virus is transmitted by Aedes mosquitoes, posing threat to people’s health and leading to great economic cost in many tropical and subtropical regions. We develop an ordinary differential equation model taking into account multiple strains of dengue virus. Using the model, we assess the effectiveness of human vaccination considering its waning and failure. We derive the lower bound and upper bound for the final size of the epidemic. Sensitivity analysis quantifies the impact of parameters on the basic reproduction number. Different scenarios of vaccinating humans show that it is better to vaccinate humans at early stages. We find that the cumulative number of infected humans is small when the vaccination rate is high or the waning rate is low for previously infected humans. We analyze the necessary conditions for implementing optimal control and derive the corresponding optimal solutions for mitigation dengue virus transmission by applying Pontryagin’s Maximum Principle. Our findings may provide guidance for the public health authorities to implement human vaccination and other mitigation strategies.In soybean, only one mitochondrial genome of cultispecies has been completely obtained. To explore the effect of mitochondrial genome on soybean cytoplasmic male sterility (CMS), two CMS lines and three maintainer lines were used for sequencing. Comparative analysis showed that mitochondrial genome of the CMS line was more compact than that of its maintainer line, but genes were highly conserved. Conserved and unique sequence coexisted in the genomes. Mitochondrial genomes contained different sequence lengths and copy numbers of repeats between CMS line and maintainer line. Large and short repeats mediated intramolecular and intermolecular recombination in mitochondria. Unique sequences and genes were also involved in recombination process and constituted a complex network. orf178 and orf261 were identified as CMS-associated candidate genes. find more They had sequence characteristics of reported CMS genes in other crops and could be transcribed in CMS lines but not in maintainer lines. This report reveals mitochondrial genome of soybean CMS lines and compares complete mitochondrial sequence between CMS lines and their maintainer lines.