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Tea is one of the worlds most popular and widely consumed beverages. It is a common pastime to enjoy a cup of tea in the sunshine. However, little attention has been given to understanding the possible photochemical reactions occurring beneath the calm surface of brewed tea. Epigallocatechin gallate (EGCG), which is widely used in food and beverages, is the most significant active ingredient found in tea. In this study, we investigated the presence of free radicals in both an aqueous EGCG solution and brewed tea under simulated sunlight conditions. To our surprise, we unexpectedly observed the production of hydroxyl radicals (•OH) in brewed tea. It was found that sunlight irradiation played a critical role in the formation of •OH, independent of the presence of metal ions. Furthermore, we demonstrated that the •OH generated from the EGCG aqueous solution induced cell cytotoxicity and DNA damage in vitro. Considering the crucial role of •OH in various fields, including human health and the environment, it is important to further explore the practical implications of •OH production in brewed tea under sunlight. In summary, our study unveils the unexpected formation of •OH in brewed tea and emphasizes the significance of sunlight-induced reactions. The observed cytotoxic and DNA-damaging effects of •OH emphasize the importance of understanding the potential health consequences associated with tea consumption. Further research in this area will contribute to a better understanding of the broader implications of •OH production in brewed tea under sunlight.

Soil carbohydrates, such as glucose and fructose, are essential components of soil organic matter (SOM). They serve as the primary carbon and energy sources for soil microorganisms and play a crucial role in regulating SOM stability, both directly and indirectly. Despite their ecological importance, the transformation processes and forms of soil carbohydrates are still not well-understood, despite centuries of extensive study. The use of stable carbon isotopes as natural tracers offers distinct advantages over radioisotope techniques, including safety, cleanliness, and ease of control. As a result, stable carbon isotope analysis has been widely employed in soil carbon cycling research. The examination of carbon isotopic variation in carbohydrates using stable carbon isotope tracers contributes to our understanding of carbohydrate transformation and accumulation processes within the plant-soil-microorganism system. It also enhances our comprehension of soil carbon metabolism. This paper provides an introduction to the types, sources, and pretreatment methods of soil carbohydrates. Furthermore, it reviews the theory and methods of stable carbon isotope analysis as applied to carbohydrates and their relevance to the study of soil carbon cycling. Lastly, it offers a comprehensive summary of current research challenges and prospects for future advancements in soil carbon cycling research.

Recent findings regarding nicotinamide adenine dinucleotide (NAD+)-capped RNAs (NAD-RNAs) indicate that prokaryotes and eukaryotes employ noncanonical RNA capping to regulate gene expression. Two methods for transcriptome-wide analysis of NAD-RNAs, NAD captureSeq and NAD tagSeq, are based on copper-catalyzed azide-alkyne cycloaddition (CuAAC) click chemistry to label NAD-RNAs. However, copper ions can fragment/degrade RNA, interfering with the analyses. Here we report development of NAD tagSeq II, which uses copper-free, strain-promoted azide-alkyne cycloaddition (SPAAC) for labeling NAD-RNAs, followed by identification of tagged RNA by single-molecule direct RNA sequencing. We used this method to compare NAD-RNA and total transcript profiles of Escherichia coli cells in the exponential and stationary phases. We identified hundreds of NAD-RNA species in E. coli and revealed genome-wide alterations of NAD-RNA profiles in the different growth phases. Although no or few NAD-RNAs were detected from some of the most highly expressed genes, the transcripts of some genes were found to be primarily NAD-RNAs. Our study suggests that NAD-RNAs play roles in linking nutrient cues with gene regulation in E. coli.

Nicotinamide adenine diphosphate (NAD+) is a novel messenger RNA 5' cap in Escherichia coli, yeast, mammals, and Arabidopsis Transcriptome-wide identification of NAD+-capped RNAs (NAD-RNAs) was accomplished through NAD captureSeq, which combines chemoenzymatic RNA enrichment with high-throughput sequencing. NAD-RNAs are enzymatically converted to alkyne-RNAs that are then biotinylated using a copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. Originally applied to E. coli RNA, which lacks the m7G cap, NAD captureSeq was then applied to eukaryotes without extensive verification of its specificity for NAD-RNAs vs. m7G-capped RNAs (m7G-RNAs). In addition, the Cu2+ ion in the CuAAC reaction causes RNA fragmentation, leading to greatly reduced yield and loss of full-length sequence information. We developed an NAD-RNA capture scheme utilizing the copper-free, strain-promoted azide-alkyne cycloaddition reaction (SPAAC). We examined the specificity of CuAAC and SPAAC reactions toward NAD-RNAs and m7G-RNAs and found that both prefer the former, but also act on the latter. We demonstrated that SPAAC-NAD sequencing (SPAAC-NAD-seq), when combined with immunodepletion of m7G-RNAs, enables NAD-RNA identification with accuracy and sensitivity, leading to the discovery of new NAD-RNA profiles in Arabidopsis Furthermore, SPAAC-NAD-seq retained full-length sequence information. Therefore, SPAAC-NAD-seq would enable specific and efficient discovery of NAD-RNAs in prokaryotes and, when combined with m7G-RNA depletion, in eukaryotes.

RNA capping and decapping tightly coordinate with transcription, translation, and RNA decay to regulate gene expression. Proteins in the DXO/Rai1 family have been implicated in mRNA decapping and decay, and mammalian DXO was recently found to also function as a decapping enzyme for NAD+ -capped RNAs (NAD-RNA). The Arabidopsis genome contains a single gene encoding a DXO/Rai1 protein, AtDXO1. Here we show that AtDXO1 possesses both NAD-RNA decapping activity and 5'-3' exonuclease activity but does not hydrolyze the m7 G cap. The atdxo1 mutation increased the stability of NAD-RNAs and led to pleiotropic phenotypes, including severe growth retardation, pale color, and multiple developmental defects. Transcriptome profiling analysis showed that the atdxo1 mutation resulted in upregulation of defense-related genes but downregulation of photosynthesis-related genes. The autoimmunity phenotype of the mutant could be suppressed by either eds1 or npr1 mutation. However, the various phenotypes associated with the atdxo1 mutant could be complemented by an enzymatically inactive AtDXO1. The atdxo1 mutation apparently enhances post-transcriptional gene silencing by elevating levels of siRNAs. Our study indicates that AtDXO1 regulates gene expression in various biological and physiological processes through its pleiotropic molecular functions in mediating RNA processing and decay.

The 5' end of a eukaryotic mRNA transcript generally has a 7-methylguanosine (m7G) cap that protects mRNA from degradation and mediates almost all other aspects of gene expression. Some RNAs in Escherichia coli, yeast, and mammals were recently found to contain an NAD+ cap. Here, we report the development of the method NAD tagSeq for transcriptome-wide identification and quantification of NAD+-capped RNAs (NAD-RNAs). The method uses an enzymatic reaction and then a click chemistry reaction to label NAD-RNAs with a synthetic RNA tag. The tagged RNA molecules can be enriched and directly sequenced using the Oxford Nanopore sequencing technology. NAD tagSeq can allow more accurate identification and quantification of NAD-RNAs, as well as reveal the sequences of whole NAD-RNA transcripts using single-molecule RNA sequencing. Using NAD tagSeq, we found that NAD-RNAs in Arabidopsis were produced by at least several thousand genes, most of which are protein-coding genes, with the majority of these transcripts coming from

Background: The 2020 edition of the Pharmacopoeia of the People’s Republic of China (Chinese Pharmacopoeia 2020 edition) has 255 Chinese prescriptions with different dosage forms, accounting for 21.09% of the total prescriptions (1,209) in Chinese Pharmacopoeia 2020 edition. However, the scientific rationality of the phenomenon of “Different Dosage Forms of the Same Prescription” of Chinese proprietary medicine has been less explored. Based on the dosage form theory of “components in pills release slowly and take effect in slow-acting manner, while in powders release quickly and take effect in fast-acting way,” we provided the in vitro dissolution experiment and in vivo pharmacokinetics of Chuanxiong Chatiao powders and pills in order to rationalize the phenomenon of “Different Dosage Forms of the Same Prescription” of Chuanxiong Chatiao prescription.Materials and Methods: Chuanxiong Chatiao powders and pills were prepared in the laboratory referring to the preparation methods in the Chinese Pharmacopoeia 2020 edition, and the contents of tetramethylpyrazine, ferulic acid, nodakenin, and isoimperatorin were determined by the external standard method. We measured the in vitro dissolution of four analytes of Chuanxiong Chatiao powders and pills according to the second method for dissolution determination (paddle method) in the Chinese Pharmacopoeia 2020 edition, and their corresponding contents in each sampling point were determined by LC-MS/MS. We also provided a pharmacokinetic study of Chuanxiong Chatiao powders and pills. Six female domestic rabbits were divided into two groups (powder and pill groups) and given Chuanxiong Chatiao powders and pills (9.85 g/kg) by surgical administration separately. Blood samples were collected at 5, 15, 30, 45, 60, 90, 120, 150, 180, 240, 360, 480, 720, and 1,440 min after drug administration to measure the plasma concentration of the four analytes by LC-MS/MS.Results: The results of in vitro dissolution experiment showed that the dissolution rate of four analytes in the powder group was greater than that of the pill group. However, the solubilities of tetramethylpyrazine and isoimperatorin were very low in the powder and pill, which may be related to their low solubility properties. The results of the in vivo pharmacokinetic study of Chuanxiong Chatiao powders and pills showed that Tmax (h) of ferulic acid and nodakenin in the powder group was 0.420 and 0.053 times that of the pill group and t1/2 (h) of ferulic acid, nodakenin, and isoimperatorin of the powder group was 0.910, 0.262, and 0.661 times that of the pill group, respectively.Conclusion: The in vitro dissolution rate and in vivo pharmacokinetic parameters of four analytes in CXCTF could partly explain the scientific rationality of the classic theory of “丸者缓也, 散者散也” as in Chinese, which is helpful for providing a basis for the comparison of subsequent dosage forms. The results of our studies also suggest the complexity of the design of dosage forms of Chinese proprietary medicines and imply that we should pay more attention to the scientific rationality of the phenomenon of “Different Dosage Forms of the Same Prescription.”

The prediction of expressway vehicle trajectories is a crucial aspect in the development of intelligent expressways. This paper proposes a novel approach, namely the W-GRU-Attention (WGA) model, which utilizes ETC transaction data to predict trajectory selection based on historical traffic paths and previous passed gantry information. In this study, we apply the concept of word embedding models to extract contextual semantics from the historical trajectories on expressways. Additionally, we introduce an average pooling technique for converting the historical vehicle trajectory into a fixed-length Historical Trajectory Vector (HTV), enabling us to capture dependency relationships within experience paths. By combining proximity gantry vectors during transit, we accurately predict the next gantry location. Finally, our proposed method is evaluated using a real-world expressway ETC dataset. It achieves an impressive accuracy rate of 96.14% in capturing the relationship between historical trajectories and adjacent gantries, surpassing other models in path prediction. [ABSTRACT FROM AUTHOR]

A clustering algorithm is a solution for grouping a set of objects and for distribution centre location problems. But the common K-means clustering algorithm may give local optimal solutions. Swarm intelligent algorithms simulate the social behaviours of animals and avoid local optimal solutions. We employ three swarm intelligent algorithms to avoid these solutions. We propose a new algorithm for the clustering problem, the fruit-fly optimization K-means algorithm (FOA K-means). We designed a distribution centre location problem and three clustering indicators to evaluate the performance of algorithms. We compare the algorithms of K-means with the ant colony optimization algorithm (ACO K-means), particle swarm optimization algorithm (PSO K-means), and fruit-fly optimization algorithm. We find K-Means modified by the fruit-fly optimization algorithm (FOA K-means) has the best performance on convergence speed and three clustering indicators, compactness, separation, and integration. Thus, we can apply FOA K-means to improve the distribution centre location solution and the efficiency for distribution in the future.