Vascular cambium stem cells: past, present and future.

Secondary xylem and phloem originate from a lateral meristem called the vascular cambium that consists of one to several layers of meristematic cells. Recent lineage tracing studies have shown that only one of the cambial cells in each radial cell file functions as the stem cell, capable of producing both secondary xylem and phloem. Here, we first review how phytohormones and signalling peptides regulate vascular cambium formation and activity. We then propose how the stem cell concept, familiar from apical meristems, could be applied to cambium studies. Finally, we discuss how this concept could set the basis for future research.

Outcome of chairside CAD/CAM ceramic restorations on endodontically treated posterior teeth: a prospective study.

OBJECTIVE: The aim of this study was to evaluate the outcome and risk factors for chairside CAD/CAM full cusp coverage restorations on endodontically treated posterior teeth after 3 years of follow-up. METHODS: A total of 245 endodontically treated posterior teeth of 224 patients were included and restored with CAD/CAM full cusp coverage all-ceramic restorations according to a standardized protocol. Patients were recalled after treatments 1 to 3 years and underwent clinical and radiological examinations. At recall, modified FDI criteria were used to determine treatment outcomes by 2 evaluators. Success was determined when FDI scores were 1-2, and failure was indicated when FDI scores were 5. Logistic regression analysis was performed to evaluate potential risk factors. RESULTS: A total of 183 patients presented at recall, and the clinical outcomes of 201 teeth were analyzed with a recall rate of 82.0% for teeth and 81.7% for patients after 1-3 years of follow-up.185 of 201 teeth were found to have FDI scores of 1-2, and the success rate was 92%. No teeth were extracted during the follow-up period. Fourteen failed cases with an FDI score of 5 presented restoration dislocation, fracture of restoration or/and tooth. Logistic regression analysis revealed that oral parafunction (OR 2.281, 95% CI 2.2 ~ 47.5, P value 0.01) was a risk factor for success rate. CONCLUSION: Chairside CAD/CAM all-ceramic full cusp coverage restoration was (could be) a promising alternative for restoring endodontically treated posterior teeth.

Anionic Chemistry Modulation Enabled Environmental Self-Charging Aqueous Zinc Batteries: The Case of Carbonate Ions.

Anionic chemistry modulation represents a promising avenue to enhance the electrochemical performance and unlock versatile applications in cutting-edge energy storage devices. Herein, we propose a methodology that involves anionic chemistry of carbonate anions to tailor the electrochemical oxidation-reduction reactions of bismuth (Bi) electrodes, where the conversion energy barrier for Bi (0) to Bi (III) has been significantly reduced, endowing anionic full batteries with enhanced electrochemical kinetics and chemical self-charging property. The elaborately designed batteries with an air-switch demonstrate rapid self-recharging capabilities, recovering over 80 % of the electrochemical full charging capacity within a remarkably short timeframe of 1 hour and achieving a cumulative self-charging capacity of 5 Ah g-1. The aqueous self-charging battery strategy induced by carbonate anion, as proposed in this study, holds the potential for extending to various anionic systems, including seawater-based Cl- ion batteries. This work offers a universal framework for advancing next-generation multi-functional power sources.

Activating and Stabilizing a Reversible four Electron Redox Reaction of I-/I+ for Aqueous Zn-Iodine Battery.

Low capacity and poor cycle stability greatly inhibit the development of zinc-iodine batteries. Herein, a high-performance Zn-iodine battery has been reached by designing and optimizing both electrode and electrolyte. The Br- is introduced as the activator to trigger I+, and coupled with I+ forming interhalogen to stabilize I+ to achieve a four-electron reaction, which greatly promotes the capacity. And the Ni-Fe-I LDH nanoflowers serve as the confinement host to enable the reactions of I-/I+ occurring in the layer due to the spacious and stable interlayer spacing of Ni-Fe-I LDH, which effectively suppresses the iodine-species shuttle ensuring high cycling stability. As a result, the electrochemical performance is greatly enhanced, especially in specific capacity (as high as 350 mAh g-1 at 1 A g-1 far higher than two-electron transfer Zn-iodine batteries) and cycling performance (94.6 % capacity retention after 10000 cycles). This strategy provides a new way to realize high capacity and long-term stability of Zn-iodine batteries.

Effects of different supplemental levels of protease DE200 on the production performance, egg quality, and cecum microflora of laying hens.

This study aimed to investigate the effects of different levels of the protease DE200 on the performance, egg quality, organ index, and cecum microflora of Hy-line W36 laying hens. In this experiment, a total of 180 laying hens aged 300 d were randomly divided into three treatment groups and fed diets containing 0, 100, or 200 g/t DE200. The experimental period was 8 wk, including 2 wk of prefeeding and 6 wk of the formal experiment. Regular feeding was performed thrice a day and eggs were collected twice daily, and the feed intake and the egg quality were recorded. The results showed that in terms of production performance, dietary supplementation with different levels of DE200 significantly increased egg production (EP; P < 0.05) and significantly decreased the feed conversion ratio (FCR; P < 0.05) and average daily feed intake (ADFI; P < 0.05) without affecting egg weight (EW). In addition, the addition of DE200 significantly reduced the egg breakage rate (P < 0.05) and tended to increase the Haugh unit and decrease the water content of the yolk (P > 0.05). In the cecal microflora, the addition of DE200 increased the proportions of Bacteroidetes and Firmicutes at the phylum level while reducing the proportion of Fusobacteria. Furthermore, at the genus level, the addition of DE200 increased the proportions of Bacteroides and Faecalibacterium and reduced the proportion of Megamonas. This study suggested that the protease DE200 can be used as a feed supplement to improve the production performance of laying hens.

In the production of laying hens, improving the efficiency of dietary protein utilization is important. The aim of this study was to investigate the effects of the protease DE200 on the performance, egg quality and cecal microflora of Hyline white laying hens. A total of 180 laying hens aged 300 d were randomly divided into three treatment groups and fed diets containing 0, 100, or 200 g/t DE200 for 56 d. The results showed that supplementation with 100 or 200 g/t DE200 in the basal diet improved the production performance and egg quality of laying hens. DE200 (100 g/t) improved the balance of the cecal microflora, and DE200 (200 g/t) increased the richness and diversity of the cecal microflora of laying hens. Dietary supplementation with DE200 can improve the intestinal health and nutrient utilization efficiency of laying hens by improving the intestinal flora.

Adipose mesenchymal stem cells-derived exosomes attenuated hyperoxia-induced lung injury in neonatal rats via inhibiting the NF-κB signaling pathway.

OBJECTIVE: Bronchopulmonary dysplasia (BPD) is the most common chronic morbidity in extremely preterm infants. Mesenchymal stem cells-derived exosomes (MSC-Exos) therapies have shown prospects in animal models of BPD. Our study aimed to evaluate the effect of adipose mesenchymal stem cells-derived exosomes (AMSC-Exos) on BPD and the role of the NF-κB signaling pathway in this process. METHODS: The AMSCs were extracted and AMSC-Exos were isolated by ultracentrifugation method. Newborn rats were exposed to hyperoxia (90% O2) continuously for 7 days to establish a BPD model. The rats were treated with AMSC-Exos by intratracheal administration on postnatal day 4 (P4). Pulmonary morphology, pulmonary vasculature, inflammatory factors, and NF-κB were assessed. Hyperoxia-induced primary type II alveolar epithelial cells (AECIIs) and AMSC-Exos treatment with or without a pan-NF-κB inhibitor (PDTC) were established to explore the potential mechanism. RESULTS: Hyperoxia-exposed rats showed alveolar simplification with decreased radial alveolar count and increased mean linear intercept, low CD31, and vascular endothelial growth factor expression, reduced microvessel density, increased the expression of TNF-α, IL-1ß, and IL-6 and decreased the expression of IL-10, and induced NF-κB phosphorylation. AMSC-Exos protected the neonatal lung from the hyperoxia-induced arrest of alveolar and vascular development, alleviated inflammation, and inhibited NF-κB phosphorylation. Hyperoxia decreased viability, increased apoptosis, enhanced inflammation, and induced NF-κB phosphorylation of AECIIs but improved by AMSC-Exos, PDTC, or AMSC-Exos+PDTC. The effect of AMSC-Exos+PDTC in AECIIs was the same as AMSC-Exos, but more notable than PDTC alone. CONCLUSION: AMSC-Exos attenuated the hyperoxia-induced lung injury in neonatal rats by inhibiting the NF-κB signaling pathway partly.

Atherosclerotic three-layer nanomatrix vascular sheets for high-throughput therapeutic evaluation.

In vitro atherosclerosis models are essential to evaluate therapeutics before in vivo and clinical studies, but significant limitations remain, such as the lack of three-layer vascular architecture and limited atherosclerotic features. Moreover, no scalable 3D atherosclerosis model is available for making high-throughput assays for therapeutic evaluation. Herein, we report an in vitro 3D three-layer nanomatrix vascular sheet with critical atherosclerosis multi-features (VSA), including endothelial dysfunction, monocyte recruitment, macrophages, extracellular matrix remodeling, smooth muscle cell phenotype transition, inflammatory cytokine secretion, foam cells, and calcification initiation. Notably, we present the creation of high-throughput functional assays with VSAs and the use of these assays for evaluating therapeutics for atherosclerosis treatment. The therapeutics include conventional drugs (statin and sirolimus), candidates for treating atherosclerosis (curcumin and colchicine), and potential gene therapy (miR-146a-loaded liposomes). The high efficiency and flexibility of the scalable VSA functional assays should facilitate drug discovery and development for atherosclerosis.