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The terrestrial macroscopic cyanobacterium Nostoc commune exhibits remarkable resistance to desiccation stress. This species synthesizes abundant acidic water stress protein (WSPA) in cells upon desiccation and secretes it into the extracellular polysaccharide sheath upon rehydration. However, our knowledge about its cellular role in stress resistance is still rather limited. In this paper, we first revealed that WSPA also occurred in two other macroscopic cyanobacteria Nostoc flagelliforme and Nostoc sphaeroides, but it is more abundant in N. commune. The N. commune wspa1 gene was then heterologously expressed in Arabidopsis thaliana. Phenotypic observation found that WSPA1 conferred increased tolerance to osmotic stress in transgenic plants. The physiological indexes such as relative electrolyte leakage, malondialdehyde, proline accumulation and the maximal quantum efficiency of Photosystem II, were also improved in transgenic plants upon osmotic stress, compared to wild types. In addition, GFP fluorescence analysis of eGFP:: wspa1 transgenic plant showed that WSPA1 was localized in the cytoplasm. Therefore, the role of WSPA revealed by this study mainly represented its intracellular function. In general, our research suggested that WSPA may act as a stress protein and involve cellular osmotic stress resistance. [ABSTRACT FROM AUTHOR]

The demand to design lightweight semantic segmentation models on mobile devices is growing. Current U-shape structures can improve the segmentation accuracy. However, they can hardly achieve lightweight requirements due to their inefficient encoders. Besides, partial details and edges are damaged during the process of repeated downsampling. To this end, we propose an efficient and lightweight U-shape network (ELUNet) for real-time semantic segmentation. In the encoder, a light split-shuffle convolution block is designed as the key component of feature extraction to achieve high-precision segmentation in the resource-limited scene. Furthermore, we propose a bridge channel attention module in the skip connection to selectively emphasize the valuable features. In the decoder, we propose an upsample feature fusion module to capture global contextual information, significantly improving the ability of the network to extract spatial information. Moreover, we design an edge refinement module to refine the segmentation predictions further. Extensive experiments prove the effectiveness of the ELUNet on Cityscapes and Camvid benchmarks. Specifically, the ELUNet contains only 2.0M parameters and achieves 73.3% mIoU on Cityscapes validation set with the speed of 52.6 FPS for a 512 × 1024 input image on a single 1080Ti GPU. [ABSTRACT FROM AUTHOR]

Nostoc flagelliforme is a terrestrial drought-resistant cyanobacterium whose potential genetic resources remain poorly explored. In this study, we evaluated the potential stress regulation-associated functions of three candidate genes, drnf3, 5, and 9. Transcriptional analysis showed that these three genes were stress responsive. Their functions were evaluated by introducing them into the expression vector pET28a and Escherichia coli strain BL21. Each of the three transformed strains exhibited enhanced cell growth in osmotic and salt stress conditions when compared to a control strain transformed with the empty vector. Three transformed strains also showed enhanced cell growth under normal condition. These results imply that increased abiotic stress resistance may be related to the basal functions of these three genes in promoting cell growth. Their actual molecular mechanisms of stress regulation remain to be explored. However, from an applied point of view, they would serve as important candidate genes in the development of transgenic industrial strains that need to be resistant to osmotic or salt stress. [ABSTRACT FROM AUTHOR]

Highlights: [•] Longer storage results in darker solution colour or more release of pigments. [•] Longer storage results in decreased Chl a and water-soluble sugars contents. [•] Higher Fv/Fm value suggests better physiological recovery and quality. [•] Sample treatment with 1mM K+ solution for Fv/Fm detection is cost-effective. [ABSTRACT FROM AUTHOR]

Nostoc flagelliforme is a terrestrial, highly drought-tolerant cyanobacterium. However, the molecular mechanism of its drought adaptation still remains little known. In this paper, we attempted to isolate those osmotic stress-regulated cDNA fragments by traditional differential display reverse transcriptase-polymerase chain reaction (DDRT-PCR). The PCR primers were chosen and evaluated from the reported HIP1D sequence-based primers and Ea/Es primers. The physiologically recovered samples were treated with 0.7 M sorbitol for 3 h. A total of 21 cDNA fragments were obtained by DDRT-PCR, and among them, 16 are up-regulated by osmotic stress. BlastX analyses showed that these up-regulated cDNA fragments are most related to ATPases, methyltransferases, transporters, glutathione synthase, signal transduction-associated components, and other unknown proteins. They are potentially important genes for N. flagelliforme to cope with drought stress since they are distinctly up-regulated by osmotic stress. In addition, five cDNA fragments are down-regulated by osmotic stress, such as the cDNA fragment of PSII protein. They may represent those genes involved in normal physiological processes and thus were inhibited by the osmotic stress. Taken together, the interpretation of the functional clues of these osmotic stress-responsive cDNA fragments has provided us an insight into the molecular mechanism of N. flagelliforme coping with the early phase of drought stress. [ABSTRACT FROM AUTHOR]

• Sequential release hydrogel caters to physiological healing process of periodontium. • The hydrogel can adapt to the complex therapeutic conditions within the oral cavity. • Sequential antibacterial, anti-inflammatory, and bone-promoting properties. • Timely degradability provides a supportive space for alveolar bone regeneration. Periodontitis is a pathological disorder characterized by inflammation and tissue destruction; it is primarily attributed to bacterial infection and immune responses. Nevertheless, existing strategies for drug delivery in periodontal treatment are insufficient to accommodate the intricate anatomical morphology of the periodontium and the complex oral environment. Furthermore, the disordered release of antibacterial agents and bone-promoting substances are not conducive to the natural healing of periodontal tissues, thus resulting in suboptimal therapeutic outcomes for periodontitis. In this study, we successfully co-loaded methylene blue (MB) and poly(lactic-co-glycolic acid) microspheres encapsulating Sema3A into a dopamine-grafted sodium alginate hydrogel (SA-DA). Experimental evidence indicates that MB/Sema3A@SA-DA exhibits favorable injectability, adhesion, and compression resistance characteristics, thus allowing it to adapt to the intricate therapeutic conditions of the oral cavity. The prompt release of MB (within 14 h) demonstrates its high antibacterial efficacy against periodontal pathogens upon exposure to 660 nm light, thereby establishing a microenvironment conducive to osteogenesis devoid of bacterial interference. Furthermore, the protracted release of Sema3A (within 28 d) shows noteworthy osteogenic capabilities and facilitates the polarization of macrophages toward the M2 phenotype. In a rat model of periodontitis, MB/Sema3A@SA-DA can be perfectly applied in situ to local periodontal lesions, and the sequential release of MB and Sema3A effectively achieved antibacterial, anti-inflammatory, and osteogenic effects. This therapeutic system avoids the abuse of antibiotics, surgical trauma, and repetitive administration. Hence, MB/Sema3A@SA-DA emerges as a safe, effective, minimally invasive, comfortable, and cost-effective treatment strategy with considerable potential for clinical implementation in periodontitis management. [ABSTRACT FROM AUTHOR]