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ABSTRACTIntestinal stem cells (ISCs) play a pivotal role in gut physiology by governing intestinal epithelium renewal through the precise regulation of proliferation and differentiation. The gut microbiota interacts closely with the epithelium through myriad of actions, including immune and metabolic interactions, which translate into tight connections between microbial activity and ISC function. Given the diverse functions of the gut microbiota in affecting the metabolism of macronutrients and micronutrients, dietary nutrients exert pronounced effects on host-microbiota interactions and, consequently, the ISC fate. Therefore, understanding the intricate host-microbiota interaction in regulating ISC homeostasis is imperative for improving gut health. Here, we review recent advances in understanding host-microbiota immune and metabolic interactions that shape ISC function, such as the role of pattern-recognition receptors and microbial metabolites, including lactate and indole metabolites. Additionally, the diverse regulatory effects of the microbiota on dietary nutrients, including proteins, carbohydrates, vitamins, and minerals (e.g. iron and zinc), are thoroughly explored in relation to their impact on ISCs. Thus, we highlight the multifaceted mechanisms governing host–microbiota interactions in ISC homeostasis. Insights gained from this review provide strategies for the development of dietary or microbiota-based interventions to foster gut health.

Abstract Genetically lean and obese individuals have distinct intestinal microbiota and function. However, the underlying mechanisms of the microbiome heterogeneity and its regulation on epithelial function such as intestinal stem cell (ISC) fate remain unclear. Employing pigs of genetically distinct breeds (obese Meishan and lean Yorkshire), this study reveals transcriptome‐wide variations in microbial ecology of the jejunum, characterized by enrichment of active Lactobacillus species, notably the predominant Lactobacillus amylovorus (L. amylovorus), and lactate metabolism network in obese breeds. The L. amylovorus‐dominant heterogeneity is paralleled with epithelial functionality difference as reflected by highly expressed GPR81, more proliferative ISCs and activated Wnt/β‐catenin signaling. Experiments using in‐house developed porcine jejunal organoids prove that live L. amylovorus and its metabolite lactate promote intestinal organoid growth. Mechanistically, L. amylovorus and lactate activate Wnt/β‐catenin signaling in a GPR81‐dependent manner to promote ISC‐mediated epithelial proliferation. However, heat‐killed L. amylovorus fail to cause these changes. These findings uncover a previously underrepresented role of L. amylovorus in regulating jejunal stem cells via Lactobacillus‐lactate‐GPR81 axis, a key mechanism bridging breed‐driven intestinal microbiome heterogeneity with ISC fate. Thus, results from this study provide new insights into the role of gut microbiome and stem cell interactions in maintaining intestinal homeostasis.

Blockchain and distributed ledger technology (BC/DLT) provides distributed databases with decentralized governance, tamper-proof recording, high availability and non-copyable digital assets, which have made it a natural technological basis for supply chain management. In this paper, we introduce REALISTIC, a novel event-based modeling framework for supply chain networks (SCNs) that includes production processes. It extends McCarty’s Resources-Events-Agents (REA) accounting model with secure transformations, which, across the entire SCN, guarantee that certified output resources cannot be digitally produced ex nihilo, but require certified input resources of at least the same amount as what is produced. This generalizes the no-double-spend guarantee of current BC/DLT to (digital twins of) physical resources and their production. Authenticated human or robotic Internet of Things (IoT) actors digitally sign and cryptographically commit to the veracity of real-world events on an immutable database, without having to take responsibility for their aggregate consequences. User-specifiable interpretations, corresponding to queries and analytical functions in database systems, provide auditable aggregate information computed from recorded events across the entire SCN. This includes fine-grained and trustworthy tracing of final products through multiple stages of production processes, semi-finished products, quality certifications and transportation all the way back to their raw materials. We present a case study for an end-to-end coffee supply chain that tracks fine-grained and detailed information from a farmer’s coffee cherries to retail coffee bags, involving all its actors. Our model handles product provenance; auditable sustainability, quality and trade information; production processes from parchment via green to roasted coffee; product quality tests; farmer certifications; and transportation across the entire coffee supply chain. It is based on field work involving farmers, cooperatives, processors, traders, importers, and a major roasting company stretching from Colombia to Scandinavia. Its REALISTIC-based modeling is the foundation for the design of our prototype implementation, which includes Ethereum blockchain code, RDBMS-based server code and a web app client. Their source code is publicly available on GitHub.

Numerous academic and industrial fields, such as healthcare, banking, and supply chain management, are rapidly adopting and relying on blockchain technology. It has also been suggested for application in the internet of vehicles (IoV) ecosystem as a way to improve service availability and reliability. Blockchain offers decentralized, distributed and tamper-proof solutions that bring innovation to data sharing and management, but do not themselves protect privacy and data confidentiality. Therefore, solutions using blockchain technology must take user privacy concerns into account. This article reviews the proposed solutions that use blockchain technology to provide different vehicle services while overcoming the privacy leakage problem which inherently exists in blockchain and vehicle services. We analyze the key features and attributes of prior schemes and identify their contributions to provide a comprehensive and critical overview. In addition, we highlight prospective future research topics and present research problems.

The early development of blockchain technology (BCT) has already demonstrated the technology's potential to serve the needs of different industries. BCT has also become established as a popular research topic in different scientific disciplines. This paper aims at introducing how several relevant scientific disciplines—supply chain management; management, economics and finance; computer science; security engineering—see the research and education perspectives for BCT. A field review is conducted to present challenges and opportunities of BCT, as well as suggestions for future research and education on the topic as seen from the selected different perspectives. The paper also presents methods for combining relevant disciplines in a modular online course to address the stated challenges and promote interdisciplinary blockchain education.

Intestinal microbiota is necessary for the guarantee of intestinal mucosal barrier. However, the detailed effect of probiotics on porcine intestinal development, especially in the early life, is still unclear. In this study, we treated 3-day-old newborn piglets with Lactobacillus reuteri (L. reuteri) D8 and observed its beneficial effect on piglets. The body weights, villus height, and crypt depth of jejunum were all significantly increased after L. reuteri treatment in piglets. L. reuteri also significantly increased the proliferation index of PCNA+ cells in the crypt, as well as c-Myc and Tcf4 expressions. Furthermore, L. reuteri also enhanced intestinal mucosal barrier with the increase of goblet cells and antimicrobial peptides (AMPs) expressions of Muc2, Lyz1, and pBD1. The well development of Peyer's patches and increased number of CD3+ T cells, combined with increased expression of IL-4 and IFN-γ, also demonstrated the immune stimulation effect of L. reuteri D8. This study demonstrated that L. reuteri promotes the development of intestine mucosal system and maintains intestinal mucosal barrier in newborn piglets.

The conditions for microwave-assisted extraction (MAE) of total flavonoids (TF) and total phenols (TP), and antioxidant activity from celery (Apium graveolens L.) leaves by response surface methodology (RSM) were optimised. The 3-level, 3-factorial Box-Behnken design (BBD) was employed to study three main extraction conditions: microwave power (300-500 W), solid-solvent ratio (15-30 ml/g), and ethanol concentration (50-80%). It was found that microwave power of 500 W at 30 ml/g solid-solvent ratio with 75.6% (v/v) ethanol concentration was the most optimum conditions for the extraction of TF and TP from celery leaves with the consequent high antioxidant activity measured by the DPPH inhibition rate. Using the optimum extraction conditions, the extraction yields of TF and TP were 0.62 g RUE/100 g DW, 3.01 g GAE/100 g DW, respectively, and the DPPH inhibition rate was 88%. The results indicated that the nutritional quality of celery (Apium graveolens L.) leaves could be improved significantly by optimising the extraction process of MAE using response surface methodology.

GRAS genes encode plant-specific transcription factors that play important roles in plant growth and development. However, little is known about the GRAS gene family in apple. In this study, 127 GRAS genes were identified in the apple (Malus domestica Borkh.) genome and named MdGRAS1 to MdGRAS127 according to their chromosomal locations. The chemical characteristics, gene structures and evolutionary relationships of the MdGRAS genes were investigated. The 127 MdGRAS genes could be grouped into eight subfamilies based on their structural features and phylogenetic relationships. Further analysis of gene structures, segmental and tandem duplication, gene phylogeny and tissue-specific expression with ArrayExpress database indicated their diversification in quantity, structure and function. We further examined the expression pattern of MdGRAS genes during apple flower induction with transcriptome sequencing. Eight higher MdGRAS (MdGRAS6, 26, 28, 44, 53, 64, 107, and 122) genes were surfaced. Further quantitative reverse transcription PCR indicated that the candidate eight genes showed distinct expression patterns among different tissues (leaves, stems, flowers, buds, and fruits). The transcription levels of eight genes were also investigated with various flowering related treatments (GA3, 6-BA, and sucrose) and different flowering varieties (Yanfu No. 6 and Nagafu No. 2). They all were affected by flowering-related circumstance and showed different expression level. Changes in response to these hormone or sugar related treatments indicated their potential involvement during apple flower induction. Taken together, our results provide rich resources for studying GRAS genes and their potential clues in genetic improvement of apple flowering, which enriches biological theories of GRAS genes in apple and their involvement in flower induction of fruit trees.