The role of cell identity in the response to cell wall perturbation in the Arabidopsis thaliana primary root

The cell wall is a defining feature of plant cells. It is a rigid, yet flexible, layer surrounding each cell outside the plasma membrane and is mainly composed of polysaccharides such as cellulose, hemicellulose, and pectin, as well asm to a lesser extent, phenolic compounds such as lignin and structural proteins. Plant cell wall is central to nearly all aspects of plant. Its biosynthesis and remodeling are essential for cell division, expansion and differentiation, the fundamental events through plant growth and development. In brief, cell walls shape the cells, which is crucial for organ formation, provide mechanical support to the plant, control cell-to-cell adhesion, form the interface between cells, which is indispensable for cellular communication, and regulate plant-pathogen/environment interactions. As plants permanently face intrinsic and extrinsic cues from developmental programs and the environment, this information must be correctly conveyed into the cells in order to adjust the plant’s growth behavior and reallocate the resources accordingly. Therefore, a cell wall surveillance and signalling system must exist to ensure transmission of the information. Roots form the hidden half of the plant and perform numerous physical and physiological functions such as anchoring, nutrient uptake and transport. The primary root of the model organism in plant research, Arabidopsis thaliana, is formed with different tissues organized as longitudinal cell files that are radially patterned in a concentric manner, which provides an easily accessible model to study plant development. By using this model, previous studies in our lab have revealed the plasma membrane residing RECEPTOR LIKE PROTEIN (RLP)44 as key factor for cell wall surveillance and signalling. RLP44 monitors pectin status in the cell wall and transduces the signal of changes in cell wall integrity through interaction with the brassinosteroid receptor BRI1, which in turn activates a well-described signalling cascade to regulate plant growth transcriptionally. As in plants, different tissues fulfill distinct biological functions and have similar, yet distinguishable, characteristics in their cell walls, investigation of RLP44-mediated cell wall signalling in tissue-specific context would bring more insights into how plants co-ordinates its growth and development in responses to cell wall changes at tissue level. To do so, we made use of the recently developed GreenGate cloning technique and the dexamethasone-inducible system pOp6/GR-LhG4. By using promoters driving expression specifically in different cell types/ tissues, we ectopically expressed pectin-modifying gene PECTIN METHYLESTERASE INHIBITOR 5 (PMEI5) and studied the responses of the plant to the loss of cell wall integrity. Here, we showed that cell wall homeostasis had pronounced impact on root growth, especially on in root morphogenesis, meristem size control, division plane determination through CDS maintenance, and tissue patterning. This influence was manifested as varying phenotypes at tissue level, implemented probably through crosstalks between brassinosteroid and other hormone signalling pathways in both cell-autonomous and non cell-autonomous manner. Besides, the previously described RLP44-mediated cell wall signalling exerts its role in a cell type/tissue-specific way and other cell wall sensing and signalling mechanisms are also possibly involved in the responses to cell wall perturbation. However, biochemical and histological characterization of cell wall properties as well as genetic studies for discovering the underlying molecular mechanisms will be necessary to further understand the role of cell identity in cell wall signalling and plant growth regulation

Efficacy of some selected neo-adjuvant chemotherapy regimens in the treatment of advanced oral squamous cell carcinoma, and their effects on immune function

Purpose: To investigate the clinical efficacy of different neo-adjuvant chemotherapy (NACT) regimens in the treatment of advanced oral squamous cell carcinoma (OSCC), and their influence on immune function of the patients.Methods: Advanced OSCC patients (n = 94) who received NACT served as subjects in this study. They were assigned to 2 different treatment groups. Forty patients received docetaxel and fluorouracil regimen (DF group), while 54 patients received taxotere, cisplatin and fluorouracil regimen (TPF group). Surgery was performed after NACT. Changes in clinical efficacy and immune function were monitored in both groups. The clinical baseline data of patients were assessed prior to the treatments. Independent indicators of prognosis were determined using Cox regression analysis (CRA).Results: Clinical treatment efficacy was higher in TPF group than in DF group (p < 0.05). Objective remission rate (ORR) in DF group was lower than that in TPF group (p < 0.05). After chemotherapy, both groups had increased levels of CD4+ and CD4+/CD8+, and reduced level of CD8+, when compared with pre-chemotherapy values, with higher levels of CD4+ and CD4+/CD8+ ratio, and lower level of CD8+ in TPF group than in DF group (p < 0.05). Multivariate CRA revealed that the independent factors for prognosis of oral carcinoma (OC) were tumor node metastasis (TNM) stage and lymph node metastasis.Conclusion: These results indicate that TFP regimen improves clinical efficacy and immune function in patients with advanced OSCC

Structural and spectral dynamics of single-crystalline Ruddlesden-Popper phase halide perovskite blue light-emitting diodes.

Achieving perovskite-based high-color purity blue-emitting light-emitting diodes (LEDs) is still challenging. Here, we report successful synthesis of a series of blue-emissive two-dimensional Ruddlesden-Popper phase single crystals and their high-color purity blue-emitting LED demonstrations. Although this approach successfully achieves a series of bandgap emissions based on the different layer thicknesses, it still suffers from a conventional temperature-induced device degradation mechanism during high-voltage operations. To understand the underlying mechanism, we further elucidate temperature-induced device degradation by investigating the crystal structural and spectral evolution dynamics via in situ temperature-dependent single-crystal x-ray diffraction, photoluminescence (PL) characterization, and density functional theory calculation. The PL peak becomes asymmetrically broadened with a marked intensity decay, as temperature increases owing to [PbBr6]4- octahedra tilting and the organic chain disordering, which results in bandgap decrease. This study indicates that careful heat management under LED operation is a key factor to maintain the sharp and intense emission

Block-Sparse Coding-Based Machine Learning Approach for Dependable Device-Free Localization in IoT Environment

Device-free localization (DFL) locates targets without equipping with wireless devices or tag under the Internet-of-Things (IoT) architectures. As an emerging technology, DFL has spawned extensive applications in IoT environment, such as intrusion detection, mobile robot localization, and location-based services. Current DFL-related machine learning (ML) algorithms still suffer from low localization accuracy and weak dependability/robustness because the group structure has not been considered in their location estimation, which leads to a undependable process. To overcome these challenges, we propose in this work a dependable block-sparse scheme by particularly considering the group structure of signals. An accurate and robust ML algorithm named block-sparse coding with the proximal operator (BSCPO) is proposed for DFL. In addition, a severe Gaussian noise is added in the original sensing signals for preserving network-related privacy as well as improving the dependability of model. The real-world data-driven experimental results show that the proposed BSCPO achieves robust localization and signal-recovery performance even under severely noisy conditions and outperforms state-of-the-art DFL methods. For single-target localization, BSCPO retains high accuracy when the signal-to-noise ratio exceeds-10 dB. BSCPO is also able to localize accurately under most multitarget localization test cases

Neutrophil heterogeneity and aging: implications for COVID-19 and wound healing

Neutrophils play a critical role in the immune response to infection and tissue injury. However, recent studies have shown that neutrophils are a heterogeneous population with distinct subtypes that differ in their functional properties. Moreover, aging can alter neutrophil function and exacerbate immune dysregulation. In this review, we discuss the concept of neutrophil heterogeneity and how it may be affected by aging. We then examine the implications of neutrophil heterogeneity and aging for COVID-19 pathogenesis and wound healing. Specifically, we summarize the evidence for neutrophil involvement in COVID-19 and the potential mechanisms underlying neutrophil recruitment and activation in this disease. We also review the literature on the role of neutrophils in the wound healing process and how aging and neutrophil heterogeneity may impact wound healing outcomes. Finally, we discuss the potential for neutrophil-targeted therapies to improve clinical outcomes in COVID-19 and wound healing